The document describes research on designing artificial nonlinear robust controllers for robot manipulators. It discusses two classical nonlinear robust controllers - sliding mode controller (SMC) and computed torque controller (CTC) - and their limitations when applied to systems with uncertainties. It then proposes applying fuzzy logic methodology to these classical controllers to reduce their limitations. Specifically, it develops a fuzzy sliding mode controller with tunable gain (GTFSMC) and a computed torque-like controller with tunable gain (GTCTLC) that use fuzzy logic rules to eliminate the mathematical nonlinear dynamics and reduce chattering through optimization of the tunable gain parameter. The controllers aim to achieve satisfactory performance for robot manipulators operating in unknown environments with uncertainties and disturbances.
Design Auto Adjust Sliding Surface Slope: Applied to Robot ManipulatorWaqas Tariq
The main target in this paper is to present the nonlinear methods in order to control the robot manipulators and also the related results. Also the important role of sliding surface slope in sliding mode fuzzy control of robot manipulator should be considered. Sliding mode controller (SMC) is a significant nonlinear controller in certain and uncertain dynamic parameters systems. To solve the chattering phenomenon, this paper complicated two methods to each other; boundary layer method and applied fuzzy logic in sliding mode methodology. To remove the chattering sliding surface slope also played important role so this paper focused on the auto tuning this important coefficient to have the best results by applied mathematical model free methodology. Auto tuning methodology has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 s, steady state error = 1e-9 and RMS error=0.0001632).
Evaluation Performance of 2nd Order Nonlinear System: Baseline Control Tunabl...Waqas Tariq
Design a nonlinear controller for second order nonlinear uncertain dynamical systems (e.g., internal combustion engine) is one of the most important challenging works. This paper focuses on the comparative study between two important nonlinear controllers namely; computed torque controller (CTC) and sliding mode controller (SMC) and applied to internal combustion (IC) engine in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller and computed torque controller are selected. Pure SMC and CTC can be used to control of partly known nonlinear dynamic parameters of IC engine. Pure sliding mode controller and computed torque controller have difficulty in handling unstructured model uncertainties. To solve this problem applied linear error-based tuning method to sliding mode controller and computed torque controller for adjusting the sliding surface gain (ë ) and linear inner loop gain (K). Since the sliding surface gain (ë) and linear inner loop gain (K) are adjusted by linear error-based tuning method. In this research new ë and new K are obtained by the previous ë and K multiple gains updating factor(á). The results demonstrate that the error-based linear SMC and CTC are model-based controllers which works well in certain and uncertain system. These controllers have acceptable performance in presence of uncertainty.
Design Error-based Linear Model-free Evaluation Performance Computed Torque C...Waqas Tariq
Design a nonlinear controller for second order nonlinear uncertain dynamical systems is one of the most important challenging works. This research focuses on the design, implementation and analysis of a model-free linear error-based tuning computed torque controller for highly nonlinear dynamic second order system, in presence of uncertainties. In order to provide high performance nonlinear methodology, computed torque controller is selected. Pure computed torque controller can be used to control of partly known nonlinear dynamic parameters of nonlinear systems. Conversely, pure computed torque controller is used in many applications; it has an important drawback namely; nonlinear equivalent dynamic formulation in uncertain dynamic parameter. In order to solve the uncertain nonlinear dynamic parameters, implement easily and avoid mathematical model base controller, model-free performance/error-based linear methodology with three inputs and one output is applied to pure computed torque controller. The results demonstrate that the error-based linear tuning computed torque controller is a model-based controllers which works well in certain and uncertain system. Pure computed torque controller has difficulty in handling unstructured model uncertainties. To solve this problem applied linear model-free error -based tuning method to computed torque controller for adjusting the linear inner loop gain (K ). Since the linear inner loop gain (K) is adjusted by linear error-based tuning method, it is linear and continuous. In this research new K is obtained by the previous K multiple gain updating factor (á) which is a coefficient varies between half to two.
The developed control methodology can be used to build more efficient intelligent and precision mechatronic systems. Three degrees of freedom robot arm is controlled by adaptive sliding mode fuzzy algorithm fuzzy sliding mode controller (SMFAFSMC). This plant has 3 revolute joints allowing the corresponding links to move horizontally. Control of robotic manipulator is very important in field of robotic, because robotic manipulators are Multi-Input Multi-Output (MIMO), nonlinear and most of dynamic parameters are uncertainty. Design strong mathematical tools used in new control methodologies to design adaptive nonlinear robust controller with acceptable performance in this controller is the main challenge. Sliding mode methodology is a nonlinear robust controller which can be used in uncertainty nonlinear systems, but pure sliding mode controller has chattering phenomenon and nonlinear equivalent part in uncertain system therefore the first step is focused on eliminate the chattering and in second step controller is improved with regard to uncertainties. Sliding function is one of the most important challenging in artificial sliding mode algorithm which this problem in order to solved by on-line tuning method. This paper focuses on adjusting the sliding surface slope in fuzzy sliding mode controller by sliding mode fuzzy algorithm.
Methodology of Mathematical error-Based Tuning Sliding Mode ControllerCSCJournals
Design a nonlinear controller for second order nonlinear uncertain dynamical systems is one of the most important challenging works. This paper focuses on the design of a chattering free mathematical error-based tuning sliding mode controller (MTSMC) for highly nonlinear dynamic robot manipulator, in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller is selected. Pure sliding mode controller can be used to control of partly known nonlinear dynamic parameters of robot manipulator. Conversely, pure sliding mode controller is used in many applications; it has an important drawback namely; chattering phenomenon which it can causes some problems such as saturation and heat the mechanical parts of robot manipulators or drivers. In order to reduce the chattering this research is used the switching function in presence of mathematical error-based method instead of switching function method in pure sliding mode controller. The results demonstrate that the sliding mode controller with switching function is a model-based controllers which works well in certain and partly uncertain system. Pure sliding mode controller has difficulty in handling unstructured model uncertainties. To solve this problem applied mathematical model-free tuning method to sliding mode controller for adjusting the sliding surface gain (ë ). Since the sliding surface gain (ë) is adjusted by mathematical model free-based tuning method, it is nonlinear and continuous. In this research new ë is obtained by the previous ë multiple sliding surface slopes updating factor (á). Chattering free mathematical error-based tuning sliding mode controller is stable controller which eliminates the chattering phenomenon without to use the boundary layer saturation function. Lyapunov stability is proved in mathematical error-based tuning sliding mode controller with switching (sign) function. This controller has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 second, steady state error = 1e-9 and RMS error=1.8e-12).
Design of Model Free Adaptive Fuzzy Computed Torque Controller for a Nonlinea...Waqas Tariq
In this study, a model free adaptive fuzzy computed torque controller (AFCTC) is designed for a two-degree-of freedom robot manipulator to rich the best performance. Computed torque controller is studied because of its high performance. AFCTC has been also included in this study because of its robust character and high performance. Besides, this control method can be applied to non-linear systems easily. Today, robot manipulators are used in unknown and unstructured environment and caused to provide sophisticated systems, therefore strong mathematical tools are used in new control methodologies to design adaptive nonlinear robust controller with acceptable performance (e.g., minimum error, good trajectory, disturbance rejection). The strategies of control robot manipulator are classified into two main groups: classical and non-classical methods, however both classical and non-classical theories have been applied successfully in many applications, but they also have some limitation. One of the most important nonlinear robust controller that can used in uncertainty nonlinear systems, are computed torque controller. This paper is focuses on applied non-classical method in robust classical method to reduce the limitations. Therefore adaptive fuzzy computed torque controller will be presented in this paper.
In this research, a model free sliding mode fuzzy adaptive inverse dynamic fuzzy controller (SMFIDFC) is designed for a robot manipulator to rich the best performance. Inverse dynamic controller is considered because of its high performance in certain system. Fuzzy methodology has been included in inverse dynamic to keep away from design nonlinear controller based on dynamic model. Sliding mode fuzzy adaptive methodology is applied to model free controller to have better result in presence of structure and unstructured uncertainties. Besides, this control method can be applied to non-linear systems easily. Today, strong mathematical tools are used in new control methodologies to design adaptive nonlinear controller with satisfactory output results (e.g., minimum error, good trajectory, disturbance rejection).
Artificial Chattering Free on-line Fuzzy Sliding Mode Algorithm for Uncertain...CSCJournals
In this research, an artificial chattering free adaptive fuzzy sliding mode control design and application to uncertain robotic manipulator has proposed in order to design high performance nonlinear controller in the presence of uncertainties. Regarding to the positive points in sliding mode controller, fuzzy logic controller and adaptive method, the output has improved. Each method by adding to the previous controller has covered negative points. The main target in this research is design of model free estimator on-line sliding mode fuzzy algorithm for robot manipulator to reach an acceptable performance. Robot manipulators are highly nonlinear, and a number of parameters are uncertain, therefore design model free controller using both analytical and empirical paradigms are the main goal. Although classical sliding mode methodology has acceptable performance with known dynamic parameters such as stability and robustness but there are two important disadvantages as below: chattering phenomenon and mathematical nonlinear dynamic equivalent controller part. To solve the chattering fuzzy logic inference applied instead of dead zone function. To solve the equivalent problems in classical sliding mode controller this paper focuses on applied fuzzy logic method in classical controller. This algorithm works very well in certain environment but in uncertain or various dynamic parameters, it has slight chattering phenomenon. The system performance in sliding mode controller and fuzzy sliding mode controller are sensitive to the sliding function. Therefore, compute the optimum value of sliding function for a system is the next challenge. This problem has solved by adjusting sliding function of the adaptive method continuously in real-time. In this way, the overall system performance has improved with respect to the classical sliding mode controller. This controller solved chattering phenomenon as well as mathematical nonlinear equivalent part by applied fuzzy supervisory method in sliding mode fuzzy controller and tuning the sliding function.
Design Auto Adjust Sliding Surface Slope: Applied to Robot ManipulatorWaqas Tariq
The main target in this paper is to present the nonlinear methods in order to control the robot manipulators and also the related results. Also the important role of sliding surface slope in sliding mode fuzzy control of robot manipulator should be considered. Sliding mode controller (SMC) is a significant nonlinear controller in certain and uncertain dynamic parameters systems. To solve the chattering phenomenon, this paper complicated two methods to each other; boundary layer method and applied fuzzy logic in sliding mode methodology. To remove the chattering sliding surface slope also played important role so this paper focused on the auto tuning this important coefficient to have the best results by applied mathematical model free methodology. Auto tuning methodology has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 s, steady state error = 1e-9 and RMS error=0.0001632).
Evaluation Performance of 2nd Order Nonlinear System: Baseline Control Tunabl...Waqas Tariq
Design a nonlinear controller for second order nonlinear uncertain dynamical systems (e.g., internal combustion engine) is one of the most important challenging works. This paper focuses on the comparative study between two important nonlinear controllers namely; computed torque controller (CTC) and sliding mode controller (SMC) and applied to internal combustion (IC) engine in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller and computed torque controller are selected. Pure SMC and CTC can be used to control of partly known nonlinear dynamic parameters of IC engine. Pure sliding mode controller and computed torque controller have difficulty in handling unstructured model uncertainties. To solve this problem applied linear error-based tuning method to sliding mode controller and computed torque controller for adjusting the sliding surface gain (ë ) and linear inner loop gain (K). Since the sliding surface gain (ë) and linear inner loop gain (K) are adjusted by linear error-based tuning method. In this research new ë and new K are obtained by the previous ë and K multiple gains updating factor(á). The results demonstrate that the error-based linear SMC and CTC are model-based controllers which works well in certain and uncertain system. These controllers have acceptable performance in presence of uncertainty.
Design Error-based Linear Model-free Evaluation Performance Computed Torque C...Waqas Tariq
Design a nonlinear controller for second order nonlinear uncertain dynamical systems is one of the most important challenging works. This research focuses on the design, implementation and analysis of a model-free linear error-based tuning computed torque controller for highly nonlinear dynamic second order system, in presence of uncertainties. In order to provide high performance nonlinear methodology, computed torque controller is selected. Pure computed torque controller can be used to control of partly known nonlinear dynamic parameters of nonlinear systems. Conversely, pure computed torque controller is used in many applications; it has an important drawback namely; nonlinear equivalent dynamic formulation in uncertain dynamic parameter. In order to solve the uncertain nonlinear dynamic parameters, implement easily and avoid mathematical model base controller, model-free performance/error-based linear methodology with three inputs and one output is applied to pure computed torque controller. The results demonstrate that the error-based linear tuning computed torque controller is a model-based controllers which works well in certain and uncertain system. Pure computed torque controller has difficulty in handling unstructured model uncertainties. To solve this problem applied linear model-free error -based tuning method to computed torque controller for adjusting the linear inner loop gain (K ). Since the linear inner loop gain (K) is adjusted by linear error-based tuning method, it is linear and continuous. In this research new K is obtained by the previous K multiple gain updating factor (á) which is a coefficient varies between half to two.
The developed control methodology can be used to build more efficient intelligent and precision mechatronic systems. Three degrees of freedom robot arm is controlled by adaptive sliding mode fuzzy algorithm fuzzy sliding mode controller (SMFAFSMC). This plant has 3 revolute joints allowing the corresponding links to move horizontally. Control of robotic manipulator is very important in field of robotic, because robotic manipulators are Multi-Input Multi-Output (MIMO), nonlinear and most of dynamic parameters are uncertainty. Design strong mathematical tools used in new control methodologies to design adaptive nonlinear robust controller with acceptable performance in this controller is the main challenge. Sliding mode methodology is a nonlinear robust controller which can be used in uncertainty nonlinear systems, but pure sliding mode controller has chattering phenomenon and nonlinear equivalent part in uncertain system therefore the first step is focused on eliminate the chattering and in second step controller is improved with regard to uncertainties. Sliding function is one of the most important challenging in artificial sliding mode algorithm which this problem in order to solved by on-line tuning method. This paper focuses on adjusting the sliding surface slope in fuzzy sliding mode controller by sliding mode fuzzy algorithm.
Methodology of Mathematical error-Based Tuning Sliding Mode ControllerCSCJournals
Design a nonlinear controller for second order nonlinear uncertain dynamical systems is one of the most important challenging works. This paper focuses on the design of a chattering free mathematical error-based tuning sliding mode controller (MTSMC) for highly nonlinear dynamic robot manipulator, in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller is selected. Pure sliding mode controller can be used to control of partly known nonlinear dynamic parameters of robot manipulator. Conversely, pure sliding mode controller is used in many applications; it has an important drawback namely; chattering phenomenon which it can causes some problems such as saturation and heat the mechanical parts of robot manipulators or drivers. In order to reduce the chattering this research is used the switching function in presence of mathematical error-based method instead of switching function method in pure sliding mode controller. The results demonstrate that the sliding mode controller with switching function is a model-based controllers which works well in certain and partly uncertain system. Pure sliding mode controller has difficulty in handling unstructured model uncertainties. To solve this problem applied mathematical model-free tuning method to sliding mode controller for adjusting the sliding surface gain (ë ). Since the sliding surface gain (ë) is adjusted by mathematical model free-based tuning method, it is nonlinear and continuous. In this research new ë is obtained by the previous ë multiple sliding surface slopes updating factor (á). Chattering free mathematical error-based tuning sliding mode controller is stable controller which eliminates the chattering phenomenon without to use the boundary layer saturation function. Lyapunov stability is proved in mathematical error-based tuning sliding mode controller with switching (sign) function. This controller has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 second, steady state error = 1e-9 and RMS error=1.8e-12).
Design of Model Free Adaptive Fuzzy Computed Torque Controller for a Nonlinea...Waqas Tariq
In this study, a model free adaptive fuzzy computed torque controller (AFCTC) is designed for a two-degree-of freedom robot manipulator to rich the best performance. Computed torque controller is studied because of its high performance. AFCTC has been also included in this study because of its robust character and high performance. Besides, this control method can be applied to non-linear systems easily. Today, robot manipulators are used in unknown and unstructured environment and caused to provide sophisticated systems, therefore strong mathematical tools are used in new control methodologies to design adaptive nonlinear robust controller with acceptable performance (e.g., minimum error, good trajectory, disturbance rejection). The strategies of control robot manipulator are classified into two main groups: classical and non-classical methods, however both classical and non-classical theories have been applied successfully in many applications, but they also have some limitation. One of the most important nonlinear robust controller that can used in uncertainty nonlinear systems, are computed torque controller. This paper is focuses on applied non-classical method in robust classical method to reduce the limitations. Therefore adaptive fuzzy computed torque controller will be presented in this paper.
In this research, a model free sliding mode fuzzy adaptive inverse dynamic fuzzy controller (SMFIDFC) is designed for a robot manipulator to rich the best performance. Inverse dynamic controller is considered because of its high performance in certain system. Fuzzy methodology has been included in inverse dynamic to keep away from design nonlinear controller based on dynamic model. Sliding mode fuzzy adaptive methodology is applied to model free controller to have better result in presence of structure and unstructured uncertainties. Besides, this control method can be applied to non-linear systems easily. Today, strong mathematical tools are used in new control methodologies to design adaptive nonlinear controller with satisfactory output results (e.g., minimum error, good trajectory, disturbance rejection).
Artificial Chattering Free on-line Fuzzy Sliding Mode Algorithm for Uncertain...CSCJournals
In this research, an artificial chattering free adaptive fuzzy sliding mode control design and application to uncertain robotic manipulator has proposed in order to design high performance nonlinear controller in the presence of uncertainties. Regarding to the positive points in sliding mode controller, fuzzy logic controller and adaptive method, the output has improved. Each method by adding to the previous controller has covered negative points. The main target in this research is design of model free estimator on-line sliding mode fuzzy algorithm for robot manipulator to reach an acceptable performance. Robot manipulators are highly nonlinear, and a number of parameters are uncertain, therefore design model free controller using both analytical and empirical paradigms are the main goal. Although classical sliding mode methodology has acceptable performance with known dynamic parameters such as stability and robustness but there are two important disadvantages as below: chattering phenomenon and mathematical nonlinear dynamic equivalent controller part. To solve the chattering fuzzy logic inference applied instead of dead zone function. To solve the equivalent problems in classical sliding mode controller this paper focuses on applied fuzzy logic method in classical controller. This algorithm works very well in certain environment but in uncertain or various dynamic parameters, it has slight chattering phenomenon. The system performance in sliding mode controller and fuzzy sliding mode controller are sensitive to the sliding function. Therefore, compute the optimum value of sliding function for a system is the next challenge. This problem has solved by adjusting sliding function of the adaptive method continuously in real-time. In this way, the overall system performance has improved with respect to the classical sliding mode controller. This controller solved chattering phenomenon as well as mathematical nonlinear equivalent part by applied fuzzy supervisory method in sliding mode fuzzy controller and tuning the sliding function.
Design Novel Lookup Table Changed Auto Tuning FSMC: Applied to Robot ManipulatorCSCJournals
Refer to this paper, design lookup table changed adaptive fuzzy sliding mode controller with minimum rule base and good response in presence of structure and unstructured uncertainty is presented. However sliding mode controller is one of the robust nonlinear controllers but when this controller is applied to robot manipulator with highly nonlinear and uncertain dynamic function; caused to be challenged in control. Sliding mode controller in presence of uncertainty has two most important drawbacks; chattering and nonlinear equivalent part which proposed method is solved these challenges with look up table change methodology. This method is based on self tuning methodology therefore artificial intelligence (e.g., fuzzy logic method) is played important role to design proposed method. This controller has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 s, steady state error = 1e-9 and RMS error=0.00017).
Novel Artificial Control of Nonlinear Uncertain System: Design a Novel Modifi...Waqas Tariq
This research is focused on novel particle swarm optimization (PSO) SISO Lyapunov based fuzzy estimator sliding mode algorithms derived in the Lyapunov sense. The stability of the closed-loop system is proved mathematically based on the Lyapunov method. PSO SISO fuzzy compensate sliding mode method design a SISO fuzzy system to compensate for the dynamic model uncertainties of the nonlinear dynamic system and chattering also solved by nonlinear fuzzy saturation like method. Adjust the sliding function is played important role to reduce the chattering phenomenon and also design acceptable estimator applied to nonlinear classical controller so PSO method is used to off-line tuning. Classical sliding mode control is robust to control model uncertainties and external disturbances. A sliding mode method with a switching control low guarantees the stability of the certain and/or uncertain system, but the addition of the switching control low introduces chattering into the system. One way to reduce or eliminate chattering is to insert a nonlinear (fuzzy) boundary like layer method inside of a boundary layer around the sliding surface. Classical sliding mode control method has difficulty in handling unstructured model uncertainties. One can overcome this problem by applied fuzzy inference system into sliding mode algorithm to design and estimate model-free nonlinear dynamic equivalent part. To approximate a time-varying nonlinear dynamic system, a fuzzy system requires a large amount of fuzzy rule base. This large number of fuzzy rules will cause a high computation load. The addition of PSO method to a fuzzy sliding mode controller to tune the parameters of the fuzzy rules in use will ensure a moderate computational load. The PSO method in this algorithm is designed based on the PSO stability theorem. Asymptotic stability of the closed loop system is also proved in the sense of Lyapunov.
Design Novel Nonlinear Controller Applied to Robot Manipulator: Design New Fe...Waqas Tariq
In this paper, fuzzy adaptive base tuning feedback linearization fuzzy methodology to adaption gain is introduced. The system performance in feedback linearization controller and feedback linearization fuzzy controller are sensitive to the main controller coefficient. Therefore, compute the optimum value of main controller coefficient for a system is the main important challenge work. This problem has solved by adjusting main fuzzy controller continuously in real-time. In this way, the overall system performance has improved with respect to the classical feedback linearization controller and feedback linearization fuzzy controller. Adaptive feedback linearization fuzzy controller solved external disturbance as well as mathematical nonlinear equivalent part by applied fuzzy supervisory method in feedback linearization fuzzy controller. The addition of an adaptive law to a feedback linearization fuzzy controller to online tune the parameters of the fuzzy rules in use will ensure a moderate computational load. Refer to this research; tuning methodology can online adjust coefficient parts of the fuzzy rules. Since this algorithm for is specifically applied to a robot manipulator.
Design a nonlinear controller for second order nonlinear uncertain dynamical systems (e.g., Internal Combustion Engine) is one of the most important challenging works. This paper focuses on the design of a robust backstepping adaptive feedback linearization controller (FLC) for internal combustion (IC) engine in presence of uncertainties. In order to provide high performance nonlinear methodology, feedback linearization controller is selected. Pure feedback linearization controller can be used to control of partly unknown nonlinear dynamic parameters of IC engine. In order to solve the uncertain nonlinear dynamic parameters, implement easily and avoid mathematical model base controller, Mamdani’s performance/error-based fuzzy logic methodology with two inputs and one output and 49 rules is applied to pure feedback linearization controller. The results demonstrate that the error-based fuzzy feedback linearization controller is a model-free controllers which works well in certain and partly uncertain system. Pure feedback linearization controller and error-based feedback linearization like controller with have difficulty in handling unstructured model uncertainties. To solve this problem applied backstepping-based tuning method to error-based fuzzy feedback linearization controller for adjusting the feedback linearization controller gain (K_p,K_v ). This controller has acceptable performance in presence of uncertainty (e.g., overshoot=1%, rise time=0.48 second, steady state error = 1.3e-9 and RMS error=1.8e-11).
Position Control of Robot Manipulator: Design a Novel SISO Adaptive Sliding M...Waqas Tariq
This research focuses on design Single Input Single Output (SISO) adaptive sliding mode fuzzy PD fuzzy sliding mode algorithm with estimates the equivalent part derived in the Lyapunov sense. The stability of the closed-loop system is proved mathematically based on the Lyapunov method. Proposed method introduces a SISO fuzzy system to compensate for the model uncertainties of the system and eliminate the chattering by linear boundary layer method. This algorithm is used a SISO fuzzy system to alleviate chattering and to estimate the control gain in the control law and presented a scheme to online tune of sliding function. To attenuate the chattering phenomenon this method developed a linear boundary layer and the parameter of the sliding function is online tuned by adaptation laws. This algorithm will be analyzed and evaluated on robotic manipulators and design adaption laws of adaptive algorithms after that writing Lyapunov function candidates and prove the asymptotic convergence of the closed-loop system using Lyapunov stability theorem mathematically. Compare and evaluate proposed method and sliding mode algorithms under disturbance. In regards to the former, we will be looking at the availability of online tuning methodology and the number of fuzzy if-then rules inherent to the fuzzy system being used and the corresponding computational load. Our analysis of the results will be limited to tracking accuracy and chattering.
This paper expands a sliding mode fuzzy controller which sliding surface gain is on-line tuned by minimum fuzzy inference algorithm. The main goal is to guarantee acceptable trajectories tracking between the second order nonlinear system (robot manipulator) actual and the desired trajectory. The fuzzy controller in proposed sliding mode fuzzy controller is based on Mamdani’s fuzzy inference system (FIS) and it has one input and one output. The input represents the function between sliding function, error and the rate of error. The outputs represent torque, respectively. The fuzzy inference system methodology is on-line tune the sliding surface gain based on error-based fuzzy tuning methodology. Pure sliding mode fuzzy controller has difficulty in handling unstructured model uncertainties. To solve this problem applied fuzzy-based tuning method to sliding mode fuzzy controller for adjusting the sliding surface gain (ë ). Since the sliding surface gain (ë) is adjusted by fuzzy-based tuning method, it is nonlinear and continuous. Fuzzy-based tuning sliding mode fuzzy controller is stable model-free controller which eliminates the chattering phenomenon without to use the boundary layer saturation function. Lyapunov stability is proved in fuzzy-based tuning sliding mode fuzzy controller based on switching (sign) function. This controller has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 second, steady state error = 1e-9 and RMS error=1.8e-12).
Vibration and tip deflection control of a single link flexible manipulatorijics
In this paper, a hybrid control scheme for vibration and tip deflection control of a single link flexible
manipulator system is presented. The purpose of this control is for input tracking, vibration control of hub
angle and tip deflection control. The control scheme consists of a resonant controller and a fuzzy logic
controller (FLC).The resonant controller is used as the inner loop feedback controller for vibration control
using the resonant frequencies at different resonant modes of the system which were determined from
experiment. The fuzzy logic controller is designed as the outer loop feedback controller for the tracking
control and to achieve zero steady state error. The performance of the proposed control scheme is
investigated via simulations and the results show the effectiveness of the control scheme, in addition the
controller is tested to show it robustness using different values of payload.
Adaptive MIMO Fuzzy Compensate Fuzzy Sliding Mode Algorithm: Applied to Secon...CSCJournals
This research is focused on proposed adaptive fuzzy sliding mode algorithms with the adaptation laws derived in the Lyapunov sense. The stability of the closed-loop system is proved mathematically based on the Lyapunov method. Adaptive MIMO fuzzy compensate fuzzy sliding mode method design a MIMO fuzzy system to compensate for the model uncertainties of the system, and chattering also solved by linear saturation method. Since there is no tuning method to adjust the premise part of fuzzy rules so we presented a scheme to online tune consequence part of fuzzy rules. Classical sliding mode control is robust to control model uncertainties and external disturbances. A sliding mode method with a switching control low guarantees the stability of the certain and/or uncertain system, but the addition of the switching control low introduces chattering into the system. One way to reduce or eliminate chattering is to insert a boundary layer method inside of a boundary layer around the sliding surface. Classical sliding mode control method has difficulty in handling unstructured model uncertainties. One can overcome this problem by combining a sliding mode controller and artificial intelligence (e.g. fuzzy logic). To approximate a time-varying nonlinear dynamic system, a fuzzy system requires a large amount of fuzzy rule base. This large number of fuzzy rules will cause a high computation load. The addition of an adaptive law to a fuzzy sliding mode controller to online tune the parameters of the fuzzy rules in use will ensure a moderate computational load. The adaptive laws in this algorithm are designed based on the Lyapunov stability theorem. Asymptotic stability of the closed loop system is also proved in the sense of Lyapunov.
Control of IC Engine: Design a Novel MIMO Fuzzy Backstepping Adaptive Based F...Waqas Tariq
This paper expands a Multi Input Multi Output (MIMO) fuzzy estimator variable structure control (VSC) which controller coefficient is on-line tuned by fuzzy backstepping algorithm. The main goal is to guarantee acceptable trajectories tracking between the internal combustion engine (IC engine) air to fuel ratio and the desired input. The fuzzy controller in proposed fuzzy estimator variable structure controller is based on Lyapunov fuzzy inference system (FIS) with minimum model based rule base. The input represents the function between variable structure function, error and the rate of error. The outputs represent fuel ratio, respectively. The fuzzy backstepping methodology is on-line tune the variable structure function based on adaptive methodology. The performance of the MIMO fuzzy estimator VSC which controller coefficient is on-line tuned by fuzzy backstepping algorithm (FBAFVSC) is validated through comparison with VSC and proposed method. Simulation results signify good performance of fuel ratio in presence of uncertainty and external disturbance.
A New Estimate Sliding Mode Fuzzy Controller for Robotic ManipulatorWaqas Tariq
One of the most active research areas in field of robotics is control of robot manipulator because this system has highly nonlinear dynamic parameters and most of dynamic parameters are unknown so design an acceptable controller is the main goal in this work. To solve this challenge position new estimation sliding mode fuzzy controller is introduced and applied to robot manipulator. This controller can solve to most important challenge in classical sliding mode controller in presence of highly uncertainty, namely; chattering phenomenon based on fuzzy estimator and online tuning and equivalent nonlinear dynamic based on estimation. Proposed method has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 s, steady state error = 1e-9 and RMS error=0.0001632).
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Refer to the research, design a novel SISO adaptive fuzzy sliding algorithm inverse dynamic like method (NAIDLC) and application to robot manipulator has proposed in order to design high performance nonlinear controller in the presence of uncertainties. Regarding to the positive points in inverse dynamic controller, fuzzy logic controller and self tuning fuzzy sliding method, the output has improved. The main objective in this research is analyses and design of the adaptive robust controller based on artificial intelligence and nonlinear control. Robot manipulator is nonlinear, time variant and a number of parameters are uncertain, so design the best controller for this plant is the main target. Although inverse dynamic controller have acceptable performance with known dynamic parameters but regarding to uncertainty, this controller\'s output has fairly fluctuations. In order to solve this problem this research is focoused on two methodology the first one is design a fuzzy inference system as a estimate nonlinear part of main controller but this method caused to high computation load in fuzzy rule base and the second method is focused on design novel adaptive method to reduce the computation in fuzzy algorithm.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Evolutionary Design of Backstepping Artificial Sliding Mode Based Position Al...CSCJournals
This paper expands a fuzzy sliding mode based position controller whose sliding function is on-line tuned by backstepping methodology. The main goal is to guarantee acceptable position trajectories tracking between the robot manipulator end-effector and the input desired position. The fuzzy controller in proposed fuzzy sliding mode controller is based on Mamdani’s fuzzy inference system (FIS) and it has one input and one output. The input represents the function between sliding function, error and the rate of error. The second input is the angle formed by the straight line defined with the orientation of the robot, and the straight line that connects the robot with the reference cart. The outputs represent angular position, velocity and acceleration commands, respectively. The backstepping methodology is on-line tune the sliding function based on self tuning methodology. The performance of the backstepping on-line tune fuzzy sliding mode controller (TBsFSMC) is validated through comparison with previously developed robot manipulator position controller based on adaptive fuzzy sliding mode control theory (AFSMC). Simulation results signify good performance of position tracking in presence of uncertainty and external disturbance.
On line Tuning Premise and Consequence FIS: Design Fuzzy Adaptive Fuzzy Slidi...Waqas Tariq
One of the most active research areas in the field of robotics is robot manipulators control, because these systems are multi-input multi-output (MIMO), nonlinear, and uncertainty. At present, robot manipulators is used in unknown and unstructured situation and caused to provide complicated systems, consequently strong mathematical tools are used in new control methodologies to design nonlinear robust controller with satisfactory performance (e.g., minimum error, good trajectory, disturbance rejection). Robotic systems controlling is vital due to the wide range of application. Obviously stability and robustness are the most minimum requirements in control systems; even though the proof of stability and robustness is more important especially in the case of nonlinear systems. One of the best nonlinear robust controllers which can be used in uncertainty nonlinear systems is sliding mode controller (SMC). Chattering phenomenon is the most important challenge in this controller. Most of nonlinear controllers need real time mobility operation; one of the most important devices which can be used to solve this challenge is Field Programmable Gate Array (FPGA). FPGA can be used to design a controller in a single chip Integrated Circuit (IC). In this research the SMC is designed using VHDL language for implementation on FPGA device (XA3S1600E-Spartan-3E), with minimum chattering and high processing speed (63.29 MHz).
Sliding Mode Methodology Vs. Computed Torque Methodology Using MATLAB/SIMULIN...CSCJournals
Design a nonlinear controller for second order nonlinear uncertain dynamical systems is one of the most important challenging works. This paper focuses on the design, implementation and analysis of a chattering free sliding mode controller for highly nonlinear dynamic PUMA robot manipulator and compare to computed torque controller, in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller and computed torque controller are selected. Pure sliding mode controller and computed torque controller can be used to control of partly known nonlinear dynamic parameters of robot manipulator. Conversely, pure sliding mode controller is used in many applications; it has an important drawback namely; chattering phenomenon which it can causes some problems such as saturation and heat the mechanical parts of robot manipulators or drivers. In order to reduce the chattering this research is used the linear saturation function boundary layer method instead of switching function method in pure sliding mode controller. These simulation models are developed as a part of a software laboratory to support and enhance graduate/undergraduate robotics courses, nonlinear control courses and MATLAB/SIMULINK courses at research and development company (SSP Co.) research center, Shiraz, Iran.
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
Do Personality Profiles Differ in the Pakistani Software Industry and Academi...Waqas Tariq
Effects of personality profiles and human factors in software engineering (SE) have been studied from different perspectives such as software life cycle, team performance, software quality attributes and so on. This study intends to compare personality profiles of software engineers in academia and industry. In this survey we have collected personality profiles of software engineers from academia and the local industry in Pakistan. According to the Myers-Briggs Type Indicator (MBTI) instrument, the most prominent personality type among academicians is a combination of Introversion, Sensing, Thinking, and Judging (ISTJ). However the most dominant personality type among software engineers in industry is a combination of Extroversion, Sensing, Thinking, and Judging (ESTJ). The results of study establish that software engineers working in industry are mostly extroverts as compared to those in academia who tend to be introverts. Sensing, Thinking, and Judging (STJ) however remain common in the dominant personality types of software engineers, both in industry and academia.
Usability of User Interface Styles for Learning Graphical Software ApplicationsWaqas Tariq
This paper examines usability of different user interface styles for learning graphical software applications, namely Adobe Flash CS4 and Microsoft Expression blend 4. An empirical study was performed to investigate the usability attributes of effectiveness, efficiency and satisfaction scores for learning the graphical software applications. There were 32 participants recruited whom consist of interface designers and software developers. A set of 7 tasks was designed to compare the different effects of user interface styles including graphical user interface (GUI) and command line interface (CLI). User Performance variables (effectiveness, efficiency, duration, number of errors and number of helps) were measured for tasks performed by all the participants in the test. Satisfaction score was measured using QUIS (Questionnaire for User Interface Satisfaction) tool. The result revealed that the average effectiveness scores are higher than 75% for both software applications. Although Adobe Flash CS4 gained slightly higher on effectiveness, Microsoft Expression Blend 4 obtained better results in terms of efficiency, duration, errors and helps. The user satisfaction rates also showed Microsoft Expression Blend 4 gained higher satisfaction comparing Adobe Flash CS4. Generally, both software applications gained scores above average (>3.5) for majority of the user interface satisfaction attributes of software regardless of users’ background.
Design Novel Lookup Table Changed Auto Tuning FSMC: Applied to Robot ManipulatorCSCJournals
Refer to this paper, design lookup table changed adaptive fuzzy sliding mode controller with minimum rule base and good response in presence of structure and unstructured uncertainty is presented. However sliding mode controller is one of the robust nonlinear controllers but when this controller is applied to robot manipulator with highly nonlinear and uncertain dynamic function; caused to be challenged in control. Sliding mode controller in presence of uncertainty has two most important drawbacks; chattering and nonlinear equivalent part which proposed method is solved these challenges with look up table change methodology. This method is based on self tuning methodology therefore artificial intelligence (e.g., fuzzy logic method) is played important role to design proposed method. This controller has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 s, steady state error = 1e-9 and RMS error=0.00017).
Novel Artificial Control of Nonlinear Uncertain System: Design a Novel Modifi...Waqas Tariq
This research is focused on novel particle swarm optimization (PSO) SISO Lyapunov based fuzzy estimator sliding mode algorithms derived in the Lyapunov sense. The stability of the closed-loop system is proved mathematically based on the Lyapunov method. PSO SISO fuzzy compensate sliding mode method design a SISO fuzzy system to compensate for the dynamic model uncertainties of the nonlinear dynamic system and chattering also solved by nonlinear fuzzy saturation like method. Adjust the sliding function is played important role to reduce the chattering phenomenon and also design acceptable estimator applied to nonlinear classical controller so PSO method is used to off-line tuning. Classical sliding mode control is robust to control model uncertainties and external disturbances. A sliding mode method with a switching control low guarantees the stability of the certain and/or uncertain system, but the addition of the switching control low introduces chattering into the system. One way to reduce or eliminate chattering is to insert a nonlinear (fuzzy) boundary like layer method inside of a boundary layer around the sliding surface. Classical sliding mode control method has difficulty in handling unstructured model uncertainties. One can overcome this problem by applied fuzzy inference system into sliding mode algorithm to design and estimate model-free nonlinear dynamic equivalent part. To approximate a time-varying nonlinear dynamic system, a fuzzy system requires a large amount of fuzzy rule base. This large number of fuzzy rules will cause a high computation load. The addition of PSO method to a fuzzy sliding mode controller to tune the parameters of the fuzzy rules in use will ensure a moderate computational load. The PSO method in this algorithm is designed based on the PSO stability theorem. Asymptotic stability of the closed loop system is also proved in the sense of Lyapunov.
Design Novel Nonlinear Controller Applied to Robot Manipulator: Design New Fe...Waqas Tariq
In this paper, fuzzy adaptive base tuning feedback linearization fuzzy methodology to adaption gain is introduced. The system performance in feedback linearization controller and feedback linearization fuzzy controller are sensitive to the main controller coefficient. Therefore, compute the optimum value of main controller coefficient for a system is the main important challenge work. This problem has solved by adjusting main fuzzy controller continuously in real-time. In this way, the overall system performance has improved with respect to the classical feedback linearization controller and feedback linearization fuzzy controller. Adaptive feedback linearization fuzzy controller solved external disturbance as well as mathematical nonlinear equivalent part by applied fuzzy supervisory method in feedback linearization fuzzy controller. The addition of an adaptive law to a feedback linearization fuzzy controller to online tune the parameters of the fuzzy rules in use will ensure a moderate computational load. Refer to this research; tuning methodology can online adjust coefficient parts of the fuzzy rules. Since this algorithm for is specifically applied to a robot manipulator.
Design a nonlinear controller for second order nonlinear uncertain dynamical systems (e.g., Internal Combustion Engine) is one of the most important challenging works. This paper focuses on the design of a robust backstepping adaptive feedback linearization controller (FLC) for internal combustion (IC) engine in presence of uncertainties. In order to provide high performance nonlinear methodology, feedback linearization controller is selected. Pure feedback linearization controller can be used to control of partly unknown nonlinear dynamic parameters of IC engine. In order to solve the uncertain nonlinear dynamic parameters, implement easily and avoid mathematical model base controller, Mamdani’s performance/error-based fuzzy logic methodology with two inputs and one output and 49 rules is applied to pure feedback linearization controller. The results demonstrate that the error-based fuzzy feedback linearization controller is a model-free controllers which works well in certain and partly uncertain system. Pure feedback linearization controller and error-based feedback linearization like controller with have difficulty in handling unstructured model uncertainties. To solve this problem applied backstepping-based tuning method to error-based fuzzy feedback linearization controller for adjusting the feedback linearization controller gain (K_p,K_v ). This controller has acceptable performance in presence of uncertainty (e.g., overshoot=1%, rise time=0.48 second, steady state error = 1.3e-9 and RMS error=1.8e-11).
Position Control of Robot Manipulator: Design a Novel SISO Adaptive Sliding M...Waqas Tariq
This research focuses on design Single Input Single Output (SISO) adaptive sliding mode fuzzy PD fuzzy sliding mode algorithm with estimates the equivalent part derived in the Lyapunov sense. The stability of the closed-loop system is proved mathematically based on the Lyapunov method. Proposed method introduces a SISO fuzzy system to compensate for the model uncertainties of the system and eliminate the chattering by linear boundary layer method. This algorithm is used a SISO fuzzy system to alleviate chattering and to estimate the control gain in the control law and presented a scheme to online tune of sliding function. To attenuate the chattering phenomenon this method developed a linear boundary layer and the parameter of the sliding function is online tuned by adaptation laws. This algorithm will be analyzed and evaluated on robotic manipulators and design adaption laws of adaptive algorithms after that writing Lyapunov function candidates and prove the asymptotic convergence of the closed-loop system using Lyapunov stability theorem mathematically. Compare and evaluate proposed method and sliding mode algorithms under disturbance. In regards to the former, we will be looking at the availability of online tuning methodology and the number of fuzzy if-then rules inherent to the fuzzy system being used and the corresponding computational load. Our analysis of the results will be limited to tracking accuracy and chattering.
This paper expands a sliding mode fuzzy controller which sliding surface gain is on-line tuned by minimum fuzzy inference algorithm. The main goal is to guarantee acceptable trajectories tracking between the second order nonlinear system (robot manipulator) actual and the desired trajectory. The fuzzy controller in proposed sliding mode fuzzy controller is based on Mamdani’s fuzzy inference system (FIS) and it has one input and one output. The input represents the function between sliding function, error and the rate of error. The outputs represent torque, respectively. The fuzzy inference system methodology is on-line tune the sliding surface gain based on error-based fuzzy tuning methodology. Pure sliding mode fuzzy controller has difficulty in handling unstructured model uncertainties. To solve this problem applied fuzzy-based tuning method to sliding mode fuzzy controller for adjusting the sliding surface gain (ë ). Since the sliding surface gain (ë) is adjusted by fuzzy-based tuning method, it is nonlinear and continuous. Fuzzy-based tuning sliding mode fuzzy controller is stable model-free controller which eliminates the chattering phenomenon without to use the boundary layer saturation function. Lyapunov stability is proved in fuzzy-based tuning sliding mode fuzzy controller based on switching (sign) function. This controller has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 second, steady state error = 1e-9 and RMS error=1.8e-12).
Vibration and tip deflection control of a single link flexible manipulatorijics
In this paper, a hybrid control scheme for vibration and tip deflection control of a single link flexible
manipulator system is presented. The purpose of this control is for input tracking, vibration control of hub
angle and tip deflection control. The control scheme consists of a resonant controller and a fuzzy logic
controller (FLC).The resonant controller is used as the inner loop feedback controller for vibration control
using the resonant frequencies at different resonant modes of the system which were determined from
experiment. The fuzzy logic controller is designed as the outer loop feedback controller for the tracking
control and to achieve zero steady state error. The performance of the proposed control scheme is
investigated via simulations and the results show the effectiveness of the control scheme, in addition the
controller is tested to show it robustness using different values of payload.
Adaptive MIMO Fuzzy Compensate Fuzzy Sliding Mode Algorithm: Applied to Secon...CSCJournals
This research is focused on proposed adaptive fuzzy sliding mode algorithms with the adaptation laws derived in the Lyapunov sense. The stability of the closed-loop system is proved mathematically based on the Lyapunov method. Adaptive MIMO fuzzy compensate fuzzy sliding mode method design a MIMO fuzzy system to compensate for the model uncertainties of the system, and chattering also solved by linear saturation method. Since there is no tuning method to adjust the premise part of fuzzy rules so we presented a scheme to online tune consequence part of fuzzy rules. Classical sliding mode control is robust to control model uncertainties and external disturbances. A sliding mode method with a switching control low guarantees the stability of the certain and/or uncertain system, but the addition of the switching control low introduces chattering into the system. One way to reduce or eliminate chattering is to insert a boundary layer method inside of a boundary layer around the sliding surface. Classical sliding mode control method has difficulty in handling unstructured model uncertainties. One can overcome this problem by combining a sliding mode controller and artificial intelligence (e.g. fuzzy logic). To approximate a time-varying nonlinear dynamic system, a fuzzy system requires a large amount of fuzzy rule base. This large number of fuzzy rules will cause a high computation load. The addition of an adaptive law to a fuzzy sliding mode controller to online tune the parameters of the fuzzy rules in use will ensure a moderate computational load. The adaptive laws in this algorithm are designed based on the Lyapunov stability theorem. Asymptotic stability of the closed loop system is also proved in the sense of Lyapunov.
Control of IC Engine: Design a Novel MIMO Fuzzy Backstepping Adaptive Based F...Waqas Tariq
This paper expands a Multi Input Multi Output (MIMO) fuzzy estimator variable structure control (VSC) which controller coefficient is on-line tuned by fuzzy backstepping algorithm. The main goal is to guarantee acceptable trajectories tracking between the internal combustion engine (IC engine) air to fuel ratio and the desired input. The fuzzy controller in proposed fuzzy estimator variable structure controller is based on Lyapunov fuzzy inference system (FIS) with minimum model based rule base. The input represents the function between variable structure function, error and the rate of error. The outputs represent fuel ratio, respectively. The fuzzy backstepping methodology is on-line tune the variable structure function based on adaptive methodology. The performance of the MIMO fuzzy estimator VSC which controller coefficient is on-line tuned by fuzzy backstepping algorithm (FBAFVSC) is validated through comparison with VSC and proposed method. Simulation results signify good performance of fuel ratio in presence of uncertainty and external disturbance.
A New Estimate Sliding Mode Fuzzy Controller for Robotic ManipulatorWaqas Tariq
One of the most active research areas in field of robotics is control of robot manipulator because this system has highly nonlinear dynamic parameters and most of dynamic parameters are unknown so design an acceptable controller is the main goal in this work. To solve this challenge position new estimation sliding mode fuzzy controller is introduced and applied to robot manipulator. This controller can solve to most important challenge in classical sliding mode controller in presence of highly uncertainty, namely; chattering phenomenon based on fuzzy estimator and online tuning and equivalent nonlinear dynamic based on estimation. Proposed method has acceptable performance in presence of uncertainty (e.g., overshoot=0%, rise time=0.8 s, steady state error = 1e-9 and RMS error=0.0001632).
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Refer to the research, design a novel SISO adaptive fuzzy sliding algorithm inverse dynamic like method (NAIDLC) and application to robot manipulator has proposed in order to design high performance nonlinear controller in the presence of uncertainties. Regarding to the positive points in inverse dynamic controller, fuzzy logic controller and self tuning fuzzy sliding method, the output has improved. The main objective in this research is analyses and design of the adaptive robust controller based on artificial intelligence and nonlinear control. Robot manipulator is nonlinear, time variant and a number of parameters are uncertain, so design the best controller for this plant is the main target. Although inverse dynamic controller have acceptable performance with known dynamic parameters but regarding to uncertainty, this controller\'s output has fairly fluctuations. In order to solve this problem this research is focoused on two methodology the first one is design a fuzzy inference system as a estimate nonlinear part of main controller but this method caused to high computation load in fuzzy rule base and the second method is focused on design novel adaptive method to reduce the computation in fuzzy algorithm.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Evolutionary Design of Backstepping Artificial Sliding Mode Based Position Al...CSCJournals
This paper expands a fuzzy sliding mode based position controller whose sliding function is on-line tuned by backstepping methodology. The main goal is to guarantee acceptable position trajectories tracking between the robot manipulator end-effector and the input desired position. The fuzzy controller in proposed fuzzy sliding mode controller is based on Mamdani’s fuzzy inference system (FIS) and it has one input and one output. The input represents the function between sliding function, error and the rate of error. The second input is the angle formed by the straight line defined with the orientation of the robot, and the straight line that connects the robot with the reference cart. The outputs represent angular position, velocity and acceleration commands, respectively. The backstepping methodology is on-line tune the sliding function based on self tuning methodology. The performance of the backstepping on-line tune fuzzy sliding mode controller (TBsFSMC) is validated through comparison with previously developed robot manipulator position controller based on adaptive fuzzy sliding mode control theory (AFSMC). Simulation results signify good performance of position tracking in presence of uncertainty and external disturbance.
On line Tuning Premise and Consequence FIS: Design Fuzzy Adaptive Fuzzy Slidi...Waqas Tariq
One of the most active research areas in the field of robotics is robot manipulators control, because these systems are multi-input multi-output (MIMO), nonlinear, and uncertainty. At present, robot manipulators is used in unknown and unstructured situation and caused to provide complicated systems, consequently strong mathematical tools are used in new control methodologies to design nonlinear robust controller with satisfactory performance (e.g., minimum error, good trajectory, disturbance rejection). Robotic systems controlling is vital due to the wide range of application. Obviously stability and robustness are the most minimum requirements in control systems; even though the proof of stability and robustness is more important especially in the case of nonlinear systems. One of the best nonlinear robust controllers which can be used in uncertainty nonlinear systems is sliding mode controller (SMC). Chattering phenomenon is the most important challenge in this controller. Most of nonlinear controllers need real time mobility operation; one of the most important devices which can be used to solve this challenge is Field Programmable Gate Array (FPGA). FPGA can be used to design a controller in a single chip Integrated Circuit (IC). In this research the SMC is designed using VHDL language for implementation on FPGA device (XA3S1600E-Spartan-3E), with minimum chattering and high processing speed (63.29 MHz).
Sliding Mode Methodology Vs. Computed Torque Methodology Using MATLAB/SIMULIN...CSCJournals
Design a nonlinear controller for second order nonlinear uncertain dynamical systems is one of the most important challenging works. This paper focuses on the design, implementation and analysis of a chattering free sliding mode controller for highly nonlinear dynamic PUMA robot manipulator and compare to computed torque controller, in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller and computed torque controller are selected. Pure sliding mode controller and computed torque controller can be used to control of partly known nonlinear dynamic parameters of robot manipulator. Conversely, pure sliding mode controller is used in many applications; it has an important drawback namely; chattering phenomenon which it can causes some problems such as saturation and heat the mechanical parts of robot manipulators or drivers. In order to reduce the chattering this research is used the linear saturation function boundary layer method instead of switching function method in pure sliding mode controller. These simulation models are developed as a part of a software laboratory to support and enhance graduate/undergraduate robotics courses, nonlinear control courses and MATLAB/SIMULINK courses at research and development company (SSP Co.) research center, Shiraz, Iran.
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
Do Personality Profiles Differ in the Pakistani Software Industry and Academi...Waqas Tariq
Effects of personality profiles and human factors in software engineering (SE) have been studied from different perspectives such as software life cycle, team performance, software quality attributes and so on. This study intends to compare personality profiles of software engineers in academia and industry. In this survey we have collected personality profiles of software engineers from academia and the local industry in Pakistan. According to the Myers-Briggs Type Indicator (MBTI) instrument, the most prominent personality type among academicians is a combination of Introversion, Sensing, Thinking, and Judging (ISTJ). However the most dominant personality type among software engineers in industry is a combination of Extroversion, Sensing, Thinking, and Judging (ESTJ). The results of study establish that software engineers working in industry are mostly extroverts as compared to those in academia who tend to be introverts. Sensing, Thinking, and Judging (STJ) however remain common in the dominant personality types of software engineers, both in industry and academia.
Usability of User Interface Styles for Learning Graphical Software ApplicationsWaqas Tariq
This paper examines usability of different user interface styles for learning graphical software applications, namely Adobe Flash CS4 and Microsoft Expression blend 4. An empirical study was performed to investigate the usability attributes of effectiveness, efficiency and satisfaction scores for learning the graphical software applications. There were 32 participants recruited whom consist of interface designers and software developers. A set of 7 tasks was designed to compare the different effects of user interface styles including graphical user interface (GUI) and command line interface (CLI). User Performance variables (effectiveness, efficiency, duration, number of errors and number of helps) were measured for tasks performed by all the participants in the test. Satisfaction score was measured using QUIS (Questionnaire for User Interface Satisfaction) tool. The result revealed that the average effectiveness scores are higher than 75% for both software applications. Although Adobe Flash CS4 gained slightly higher on effectiveness, Microsoft Expression Blend 4 obtained better results in terms of efficiency, duration, errors and helps. The user satisfaction rates also showed Microsoft Expression Blend 4 gained higher satisfaction comparing Adobe Flash CS4. Generally, both software applications gained scores above average (>3.5) for majority of the user interface satisfaction attributes of software regardless of users’ background.
Named Entity Recognition System for Hindi Language: A Hybrid ApproachWaqas Tariq
Named Entity Recognition (NER) is a major early step in Natural Language Processing (NLP) tasks like machine translation, text to speech synthesis, natural language understanding etc. It seeks to classify words which represent names in text into predefined categories like location, person-name, organization, date, time etc. In this paper we have used a combination of machine learning and Rule based approaches to classify named entities. The paper introduces a hybrid approach for NER. We have experimented with Statistical approaches like Conditional Random Fields (CRF) & Maximum Entropy (MaxEnt) and Rule based approach based on the set of linguistic rules. Linguistic approach plays a vital role in overcoming the limitations of statistical models for morphologically rich language like Hindi. Also the system uses voting method to improve the performance of the NER system. Keywords: NER, MaxEnt, CRF, Rule base, Voting, Hybrid approach
Endurance Testing of Aircraft Electro-Hydraulic Actuator Using LabVIEWWaqas Tariq
In Aerospace Industry, Automated Test System at the qualification and certification laboratory improves characterization accuracy and plays a vital role to prove the airworthiness of the aircraft components. It is very helpful in achieving high quality standards of aircraft components by meeting the predefined qualification and certification test criteria. This paper outlines a comprehensive design and development of an Endurance Automated Test System for performing qualification and certification testing of Electro-Hydraulic (EH) Aircraft Actuator uses LabVIEW Graphical Test Software platform. This method is aimed at replacing the tedious and time consuming traditional method of performing the endurance testing for Aircraft Actuators.
An exploratory re-search for variables representative of Academic QualityWaqas Tariq
Academic institutions have been fundamental contributors of education in the society. From tapping the talents of potential students to shaping them into responsible citizens, academic institutions have at all times played a vital role. This is the reason why quality of academic institutions has been under steady scrutiny for quality. What an institution of higher studies has to offer to students seeking to pursue their studies with it then becomes imperative. The purpose of this study is to provide an insight into the various perceptions as perceived by individuals with respect to quality of academic institution. The objective of this paper is to re-present an overview of the variables critical to the quality of an academic institution of higher studies and to indicate and /or re-emphasize upon factors that stand out important to quality in this domain. A random sample of 398 graduates from varied areas of work and study expressed their opinion about factors that they considered was most significant to academic quality. Interactions, Discussions, interviews, dialogues and questionnaires were used to consolidate the results. This paper presents a list of most extensively cited variables perceived as essential to quality education. These variables are generated from a pilot survey conducted in UAE and is a segment of an ongoing research in the areas of academic quality
Satellite-and Ground-based Red Tide Detection Method and System by Means of P...Waqas Tariq
A method for detection of red tide by means of remote sensing reflectance peak shift is proposed together with suspended solid influence eliminations. Although remote sensing reflectance peak is situated at around 550nm for sea water without suffered from red tide, the peak is shifted to the longer wavelength when sea water is suffered from red tide. Based on this fact, it is capable to detect red tide using high wavelength resolution of spectroradiometers. The proposed system uses green color filtered cameras. Acquired imagery data can be transmitted through wireless LAN to Internet terminal and can be archived in server through Internet. This is the proposed ground based red tide monitoring system. The paper also proposes a method for removing suspended solid influence on red tide suffered area estimations. The proposed method and system is validated in laboratory and field experiments. The system is deployed at coastal areas of Ariake Sea in Kyushu, Japan.
Hand Segmentation Techniques to Hand Gesture Recognition for Natural Human Co...Waqas Tariq
This work is the part of vision based hand gesture recognition system for Natural Human Computer Interface. Hand tracking and segmentation are the primary steps for any hand gesture recognition system. The aim of this paper is to develop robust and efficient hand segmentation algorithm where three algorithms for hand segmentation using different color spaces with required morphological processing have were utilized. Hand tracking and segmentation algorithm (HTS) is found to be most efficient to handle the challenges of vision based system such as skin color detection, complex background removal and variable lighting condition. Noise may contain, sometime, in the segmented image due to dynamic background. An edge traversal algorithm was developed and applied on the segmented hand contour for removal of unwanted background noise.
Business Structure of Indigenous Firms in the Nigerian Construction IndustryWaqas Tariq
The roles of contracting firms in construction industry cannot be overemphasized and their structure is a function of performance and output in the industry. Sets of questionnaire were administered on construction professionals working within the contracting firms. Data obtained was analyzed using descriptive statistic (mean ranking). The study found out that the firms are medium-size firms, engaged in building construction and cannot finance projects independently prior to client financial contribution (mobilization fee). Their activities are limited to their locality and rarely get bank loans. They do not have share capital and therefore could not fund project from company capital base.
Design of the User Experience for Personalized Mobile ServicesWaqas Tariq
This article describes how user centered, and particularly co-design methods can help maximize user experience for personalized services delivered over a mobile device. The specific focus was designing for Chinese spectators at large sports events (such as football matches, swimming galas or athletics meetings). User experience was assumed to comprise user, product, social, cultural and usage context components. Co-design methods were incorporated into a semi- structured HCI design process that comprised content, conceptual, interaction and presentation design, followed by field and lab-based user evaluation. There were two co-design methods in particular which were found to be key to working effectively with Chinese users. Emotion Cards were used to help overcome some of the inhibitions of participants and to encourage them to provide more open and unequivocal design input. The User Advisory Board was a group of participants who mediated the relationship between the designer and other participants at various design stages. They helped to ensure genuine collaboration because the wider participants felt (1) less like the object of study and (2) more able to communicate their needs during the design process.
Investigating the Influence of Firm Characteristics on Export Marketing Strat...Waqas Tariq
The export performance has been studied to a great extent while fewer researches have focused the export activities of developing countries. Firm characteristics have always been found to impact export performance considerably. Furthermore, the marketing strategy applied by the firm has been an important issue related to performance. In this paper, the relationships among firm characteristics, export marketing strategies as well as export performance were investigated on the export of medical disposable products in Malaysia. Data was gathered from 22 firms by the means of a questionnaire for which the reliability of 0.85 was achieved. The statistical Chi-Square test for independence was applied for testing the hypotheses via SPSS. The results indicated that several internal firm factors namely, market knowledge, commitment, international experience and innovation affected the application of adaptation strategies. Moreover, the use of adaptation strategies and the export performance were significantly related. Finally it was concluded that firm characteristics could influence export performance indirectly and through marketing strategies.
Research on Calibration Reading Technology of High-Precision MeterWaqas Tariq
The paper proposes a way to achieve camera positioning tasks by 2D visual servoing. By observing both the camera and the features of meter reading, the camera is able to be positioned with an accuracy in hand-eye calibration. The calibration reading method is used to recognize high-precision meter reading.The paper mainly includes three parts.Firstly,the geometrical model of parallax formation is constructed and the importing error is analyzed. Secondly, the calibration reading technology of high-precision meter is designed. Finally,the experimental platform calibration reading technology is designed. The experimental results show the method is applicable to automatic recognition of high-precision meter.
An Algorithm of Policy Gradient Reinforcement Learning with a Fuzzy Controlle...Waqas Tariq
Typical fuzzy reinforcement learning algorithms take value-function based approaches, such as fuzzy Q-learning in Markov Decision Processes (MDPs), and use constant or linear functions in the consequent parts of fuzzy rules. Instead of taking such approaches, we propose a fuzzy reinforcement learning algorithm in another approach. That is the policy gradient approach. Our method can handle fuzzy sets even in the consequent part and also learn the rule weights of fuzzy rules. Specifically, we derived learning rules of membership functions and rule weights for both cases when input/output variables to/from the control system are discrete and continuous.
Solar technology offers great potential in terms of supplying the world’s energy needs. However, its current contribution to the world is still limited. The main factor is related to high initial cost of building the system. This paper will provide an up-to-date review of solar concentrators and their benefits to make solar technology affordable. It will also analyse on some of the existing solar concentrators used in the solar technology for the past four decades. The design and performance of each concentrator will be explained and compared.
Human Arm Inverse Kinematic Solution Based Geometric Relations and Optimizati...Waqas Tariq
Kinematics for robotic systems with many degrees of freedom (DOF) and high redundancy are still an open issue. Namely, computation time in robotic applications is often too high to reach good solution, for parts of the kinematic chain; the problem of inverse kinematics is not linear, as rotations are involved. This means that analytical solutions are only available in limited situations. In all other cases, alternative methods will have to be an employed.The most-used alternative is numerical solutions optimization. This paper presents a strategy based on combine’s analytical solutions with nonlinear optimization algorithm solutions to solution the IKP. A analytical solutions is used to reduce the size of problem from seven variable of joint angle to single variable and nonlinear optimization algorithm was used to find approximate solution which make the computation time is very small
Work-Family Factors and its Relationships Between Dispositional, Occupational...Waqas Tariq
This study was conducted to test the mediating effects of work-family factors on the relationships between dispositional and occupational characteristics as the independent variables and intention to stay as the dependent variable. By using self-administered research questionnaire, data was collected from 240 middle age single mother employees in Klang Valley, Malaysia. Samples were determined through simple random sampling method whereby six out of 24 single mother associations were selected to obtain research samples. Descriptive statistical analysis was conducted to describe the respondents. Pearson Product Moment Correlation was used to determine the relationships among variables and Structural Equation Modeling using AMOS version 16.0 was utilized for model testing and to verify the presence of mediation effects. Further, the Soble’s z-test was used to test whether the mediators carry the effect of the independent variables on the dependent variable. The findings indicated that there were positive relationships among variables. The results also established the presence of mediation effects between the independent and dependent variables. Organizations may utilize work-family factors as mechanism to promote longer retention among employees. Keywords: Intention to stay, work-family facilitation, family satisfaction, dispositional characteristics, occupational characteristics.
Investigation into the Impact of the Usability Factor on the Acceptance of Mo...Waqas Tariq
Both the rapid advances in wireless technologies and the high proliferation rate of mobile communication services and artefacts have had a profound impact on industry, and are beginning to offer interesting and advantageous new services. In particular, the mobile transaction (m- transaction) system has emerged, enabling users to pay for physical and digital goods and services using their mobile devices whenever they want, regardless of their location. Although it is anticipated that m-transactions will enjoy a bright future, there is apparently still reluctance among users to accept mobile transactions, particularly in Saudi Arabia. Furthermore, it is believed that usability is critical to the success and acceptance of mobile technology innovations in general, and m-transactions in particular. While most of the research into IT innovation acceptance is based on TAM (Technology Acceptance Model) and its many variants, the literature review reveals that there is little research on mobile application usability as an important antecedent factor for the success and acceptance of mobile technologies. This is particularly true in developing countries, especially the Middle East, therefore this project aims to fill this gap in the research. This paper is an extension of four previous studies by the authors, which indicated that usability is the most influential factor in Saudi users’ intentions of utilising mobile transactions. It aims to investigate and empirically test the usability level of mobile transactions from the perspective of Saudi users; this will be achieved by conducting usability experiments with real mobile applications within the target group. In other words, this study is a part of a larger research project and it serves as a validation/verification tool to answer the question “Why does the ease of use of mobile transactions have the highest impact on the intention to use mobile transactions in Saudi Arabia?” Moreover, it will produce a set of empirically-based recommendations for the developers and providers of mobile applications who are interested in the Saudi market. The results of the this study showed that the usability of the tested application, which is considered one of the most popular commercial mobile application in Saudi Arabia, (i.e. ‘Souq.com’), is unsatisfactory, with an average SUS Score of 50. Not surprisingly, this low usability negatively affected the willingness of the participants to use the application again.
The Effectiveness of Human Resource Management PracticesWaqas Tariq
An effective human resource management practices namely employee empowerment, training and development, appraisal system compensation are the main factor for the success of a firm on employee retention. In this study, we aim to study how employees regard importance of their empowerment, equity of compensation, job design through training and expectancy toward effective performance management on their retention. Quantitative data was collected using the non probability self administered questionnaire that consist of questions with 5-points Likert scales distributed to our samples of 278 individuals. By using a multiple regression analysis, it is found that a, training and development, appraisal system compensation are significant to employee retention except employee empowerment. Base on the results, training, compensation and appraisal is a fundamental consideration for University of Y lecturers¡¯ retention decision; while empowerment is less fundamental to lecturers¡¯ consideration as this can be attributed to the Asian culture characteristic of higher authority conformity.
Spatiotemporal Land Use Patterns in UrbanizationWaqas Tariq
Urban planning was very much a design and engineering exercise with the state as a single stake holder. Mega cities with millions of population, which has undergone a series of physical as well as socio-economic changes over the last 60 years. These for in different areas of India, new planning approaches require the need to understand the complicated urban land development process. GIS- Geographic Information System and remote sensing provide the advance techniques and methods for studying urban land development and assist urban planning. This research survey firstly describes the urban expansion process till now and land use changes in the inner city.
CRM Implementation in Indian Telecom Industry – Evaluating the Effectiveness ...Waqas Tariq
With the liberalization and internationalization in telecommunication, service quality has become an important means of differentiation and path to achieve business success. Such differentiation based on service quality is seen as a key source of competitiveness for many Indian firms and hence have implications for leadership in such organizations. Faced with a growing market and increasing competition, companies in the telecom business are adopting to new technological imperatives in order to outperform their competitors. These companies adapt continuously to the dynamic environment so as to survive competition. The emphasis here lies in identifying critical value adding processes and redesigning them to become customer centric. One such approach in the adoption of an IT to move towards customers is the Customer Relationship Management (CRM). The Indian Mobile Service Providers are using CRM extensively to identify the needs of the customers and stretching out ways and means to satisfy them. In this context, it is absolutely essential to study the effectiveness of the CRM being practiced by the mobile service providers. This study specifically analyses the extent to which CRM is being practiced by the mobile service providers, and identifies the effect of the service quality of the mobile service providers on the Customer Loyalty. As CRM focuses on being customer centric, it becomes essential to measure the effectiveness of CRM in terms of the degree to which the customers are advocates of the mobile service provider as well as to measure the degree to which they participate in the cross selling and up selling of the various products and services of the provider. To evaluate the effectiveness, there are lots of quantitative techniques available and some work in this area has already been done. But there is a dearth of literature focusing on the relative efficiency. One advanced operations research technique which evaluates the relative efficiency is the Frontier Analysis or Data Envelopment Analysis (DEA). This paper attempts to use Data Envelopment Analysis to assess the effectiveness of Mobile Service Providers, specifically a set of the providers offering services in Chennai, Tamil Nadu, India. The research has identified a set of input and output parameters for each Service Provider, from which the efficient frontiers (DMUs) are determined. The relative efficiency of the Service Providers are measured with respect to the efficient frontier and then analyzed. Detailed recommendations are set forth, for appropriate interventions to address the specific gaps identified through the gaps analysis. The analysis further provides useful information and opens up new avenues for future research.
PUMA-560 Robot Manipulator Position Computed Torque Control Methods Using MAT...Waqas Tariq
This paper describes the MATLAB/SIMULINK realization of the PUMA 560 robot manipulator position control methodology. This paper focuses on design, analyzed and implements nonlinear computed torque control (CTC) methods. These simulation models are developed as a part of a software laboratory to support and enhance graduate/undergraduate robotics courses, nonlinear control courses and MATLAB/SIMULINK courses at research and development company (SSP Co.) research center, Shiraz, Iran.
Design and Implementation of Sliding Mode Algorithm: Applied to Robot Manipul...Waqas Tariq
Refer to the research, review of sliding mode controller is introduced and application to robot manipulator has proposed in order to design high performance nonlinear controller in the presence of uncertainties. Regarding to the positive points in sliding mode controller, fuzzy logic controller and adaptive method, the output in most of research have improved. Each method by adding to the previous algorithm has covered negative points. Obviously robot manipulator is nonlinear, and a number of parameters are uncertain, this research focuses on comparison between sliding mode algorithm which analyzed by many researcher. Sliding mode controller (SMC) is one of the nonlinear robust controllers which it can be used in uncertainty nonlinear dynamic systems. This nonlinear controller has two challenges namely nonlinear dynamic equivalent part and chattering phenomenon. A review of sliding mode controller for robot manipulator will be investigated in this research.
Evolutionary Design of Mathematical tunable FPGA Based MIMO Fuzzy Estimator S...Waqas Tariq
In this research, a Multi Input Multi Output (MIMO) position Field Programmable Gate Array (FPGA)-based fuzzy estimator sliding mode control (SMC) design with the estimation laws derived in Lyapunov sense and application to robotic manipulator has proposed in order to design high performance nonlinear controller in the presence of uncertainties. Regarding to the positive points in sliding mode controller, fuzzy inference methodology and Lyapunov based method, the controllers output has improved. The main target in this research is analyses and design of the position MIMO artificial Lyapunov FPGA-based controller for robot manipulator in order to solve uncertainty, external disturbance, nonlinear equivalent part, chattering phenomenon, time to market and controller size using FPGA. Robot manipulators are nonlinear, time variant and a number of parameters are uncertain therefore design robust and stable controller based on Lyapunov based is discussed in this research. Studies about classical sliding mode controller (SMC) show that: although this controller has acceptable performance with known dynamic parameters such as stability and robustness but there are two important disadvantages as below: chattering phenomenon and mathematical nonlinear dynamic equivalent controller part. The first challenge; nonlinear dynamic part; is applied by inference estimator method in sliding mode controller in order to solve the nonlinear problems in classical sliding mode controller. And the second challenge; chattering phenomenon; is removed by linear method. Asymptotic stability of the closed loop system is also proved in the sense of Lyapunov. In the last part it can find the implementation of MIMO fuzzy estimator sliding mode controller on FPGA; FPGA-based fuzzy estimator sliding mode controller has many advantages such as high speed, low cost, short time to market and small device size. One of the most important drawbacks is limited capacity of available cells which this research focuses to solve this challenge. FPGA can be used to design a controller in a single chip Integrated Circuit (IC). In this research the SMC is designed using Very High Description Language (VHDL) for implementation on FPGA device (XA3S1600E-Spartan-3E), with minimum chattering.
PUMA-560 Robot Manipulator Position Sliding Mode Control Methods Using MATLAB...Waqas Tariq
This paper describes the MATLAB/SIMULINK realization, modeling and implementation of the PUMA 560 robot manipulator. This paper focuses on robot manipulator analysis and implementation and analyzed. This simulation models are developed as a part of a software laboratory to support and enhance graduate robotics courses, and MATLAB/SIMULINK courses at research and development company (SSP Co.) research center, Shiraz, Iran.
Fractional-order sliding mode controller for the two-link robot arm IJECEIAES
This study presents a control system of the two-link robot arm based on the sliding mode controller with the fractional-order. Firstly, the equations of the two-link robot arm are analyzed, then the author proposes the controller for each joint based on these equations. The controller is a sliding mode controller with its order is not an integer value. The task of the control system is controlling the torques acted on the joints so that the response angle of each link equal to the desired angle. The effectiveness of the proposed control system is demonstrated through Matlab-Simulink software. The robot model and controller are built for investigating the efficiency of the system. The result shows that the system quality is very good: there is not the chattering phenomenon of torques, the response angle of two links always follow the desired angle with the short transaction time and the static error of zero.
Improvements the direct torque control performance for an induction machine u...IJECEIAES
This article examines a solution to the major problems of induction machine control in order to achieve superior dynamic performance. Conventional direct torque control and indirect control with flux orientation have some drawbacks, such as current harmonics, torque ripples, flux ripples, and rise time. In this article, we propose a comparative analysis between previous approaches and the one using fuzzy logic. Results from the simulation show that the direct torque control method using fuzzy logic is more effective in providing a precise and fast response without overshooting, and it eliminates torque and flux fluctuations at low switching frequencies. The demonstrated improvements in dynamic performance contribute to increased operational efficiency and reliability in industrial applications.
Design of FPGA-based Sliding Mode Controller for Robot ManipulatorWaqas Tariq
One of the most active research areas in the field of robotics is robot manipulators control, because these systems are multi-input multi-output (MIMO), nonlinear, and uncertainty. At present, robot manipulators is used in unknown and unstructured situation and caused to provide complicated systems, consequently strong mathematical tools are used in new control methodologies to design nonlinear robust controller with satisfactory performance (e.g., minimum error, good trajectory, disturbance rejection). Robotic systems controlling is vital due to the wide range of application. Obviously stability and robustness are the most minimum requirements in control systems; even though the proof of stability and robustness is more important especially in the case of nonlinear systems. One of the best nonlinear robust controllers which can be used in uncertainty nonlinear systems is sliding mode controller (SMC). Chattering phenomenon is the most important challenge in this controller. Most of nonlinear controllers need real time mobility operation; one of the most important devices which can be used to solve this challenge is Field Programmable Gate Array (FPGA). FPGA can be used to design a controller in a single chip Integrated Circuit (IC). In this research the SMC is designed using VHDL language for implementation on FPGA device (XA3S1600E-Spartan-3E), with minimum chattering and high processing speed (63.29 MHz).
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Optimal Design of Super Twisting Control with PSO Algorithm for Robotic Manip...CSCJournals
Robotic manipulators are nonlinear and coupling systems exposing to external disturbance. They are used in wide industrial applications; the suitable selection of a nonlinear robust controller is required. Sliding Mode Controller (SMC) was designed to achieve these requirements, but unfortunately the chattering phenomenon was the main drawback of the conventional SMC. It leads to destructive of some components of a real system and subsequent loss in its accuracy. Hence, the design of Super-Twisting Controller (STC) is suggested for chattering elimination. In previous literatures, the accomplishment of the manual adjustment for the parameters of STC was a large burden and time consuming process. Therefore, a new combination of Particle Swarm Optimization (PSO) algorithm with STC is proposed for optimal tuning of STC parameters. The simulation results demonstrate the superiority of the super twisting technique for chattering mitigation comparing to the conventional SMC. Also, STC tuned via PSO proves its effectiveness and robustness to different types of external disturbances without the needs for the knowledge of their upper boundary values. Besides, the performance of the controlled system is faster and more accurate in the criteria of overshoot, settling time and rise time compared to the manual adjusting of super twisting controllers.
Intelligent swarm algorithms for optimizing nonlinear sliding mode controller...IJECEIAES
This work introduces an accurate and fast approach for optimizing the parameters of robot manipulator controller. The approach of sliding mode control (SMC) was proposed as it documented an effective tool for designing robust controllers for complex high-order linear and nonlinear dynamic systems operating under uncertain conditions. In this work Intelligent particle swarm optimization (PSO) and social spider optimization (SSO) were used for obtaining the best values for the parameters of sliding mode control (SMC) to achieve consistency, stability and robustness. Additional design of integral sliding mode control (ISMC) was implemented to the dynamic system to achieve the high control theory of sliding mode controller. For designing particle swarm optimizer (PSO) and social spider optimization (SSO) processes, mean square error performances index was considered. The effectiveness of the proposed system was tested with six degrees of freedom robot manipulator by using (PUMA) robot. The iteration of SSO and PSO algorithms with mean square error and objective function were obtained, with best fitness for (SSO =4.4876 푒 −6 and (PSO)=3.4948 푒 −4 .
Mathematical model analysis and control algorithms design based on state feed...hunypink
XZ-Ⅱtype rotary inverted pendulum is a typical mechatronic system; it completes real-time motion control using DSP motion controller and motor torque. In this paper, we recognize XZ-Ⅱrotational inverted pendulum and learn system composition, working principle, using method, precautions and software platform. We master how to build mathematical model and state feedback control method (pole assignment algorithm) of the one order rotational inverted pendulum system and finish simulation study of system using Mat lab. In the end we grasp debugging method of the actual system, and finish online control of the one order rotational inverted pendulum system as well.
In this paper, the tracking control scheme is presented using the framework of finite-time sliding mode control (SMC) law and high-gain observer for disturbed/uncertain multi-motor driving systems under the consideration multi-output systems. The convergence time of sliding mode control is estimated in connection with linear matrix inequalities (LMIs). The input state stability (ISS) of proposed controller was analyzed by Lyapunov stability theory. Finally, the extensive simulation results are given to validate the advantages of proposed control design.
As the robot manipulators are highly nonlinear, time varying and Multiple Input Multiple Output (MIMO)
systems, one of the most important challenges in the field of robotics is robot manipulators control with
acceptable performance. In this research paper, a simple and computationally efficient Fuzzy Logic
Controller is designed based on the Fuzzy Lyapunov Synthesis (FLS) for the position control of PUMA-560
robot manipulator. The proposed methodology enables the designer to systematically derive the rule base
thereby guarantees the stability of the controller. The methodology is model free and does not require any
information about the system nonlinearities, uncertainties, time varying parameters, etc. The performance
of any fuzzy logic controller (FLC) is greatly dependent on its inference rules. The closed-loop control
performance and stability are enhanced if more rules are added to the rule base of the FLC. However, a
large set of rules requires more on-line computational time and more parameters need to be adjusted.
Here, a Fuzzy Logic Controller is first designed and then the controller based on FLS is designed and
simulated with a minimum rule base. Finally the simulation results of the proposed controller are
compared with that of the normal Fuzzy Logic Controller and PD controlled Computed Torque Controller
(PD-CTC). Results show that the proposed controller outperformed the other controllers.
The Use of Java Swing’s Components to Develop a WidgetWaqas Tariq
Widget is a kind of application provides a single service such as a map, news feed, simple clock, battery-life indicators, etc. This kind of interactive software object has been developed to facilitate user interface (UI) design. A user interface (UI) function may be implemented using different widgets with the same function. In this article, we present the widget as a platform that is generally used in various applications, such as in desktop, web browser, and mobile phone. We also describe a visual menu of Java Swing’s components that will be used to establish widget. It will assume that we have successfully compiled and run a program that uses Swing components.
3D Human Hand Posture Reconstruction Using a Single 2D ImageWaqas Tariq
Passive sensing of the 3D geometric posture of the human hand has been studied extensively over the past decade. However, these research efforts have been hampered by the computational complexity caused by inverse kinematics and 3D reconstruction. In this paper, our objective focuses on 3D hand posture estimation based on a single 2D image with aim of robotic applications. We introduce the human hand model with 27 degrees of freedom (DOFs) and analyze some of its constraints to reduce the DOFs without any significant degradation of performance. A novel algorithm to estimate the 3D hand posture from eight 2D projected feature points is proposed. Experimental results using real images confirm that our algorithm gives good estimates of the 3D hand pose. Keywords: 3D hand posture estimation; Model-based approach; Gesture recognition; human- computer interface; machine vision.
Camera as Mouse and Keyboard for Handicap Person with Troubleshooting Ability...Waqas Tariq
Camera mouse has been widely used for handicap person to interact with computer. The utmost important of the use of camera mouse is must be able to replace all roles of typical mouse and keyboard. It must be able to provide all mouse click events and keyboard functions (include all shortcut keys) when it is used by handicap person. Also, the use of camera mouse must allow users troubleshooting by themselves. Moreover, it must be able to eliminate neck fatigue effect when it is used during long period. In this paper, we propose camera mouse system with timer as left click event and blinking as right click event. Also, we modify original screen keyboard layout by add two additional buttons (button “drag/ drop” is used to do drag and drop of mouse events and another button is used to call task manager (for troubleshooting)) and change behavior of CTRL, ALT, SHIFT, and CAPS LOCK keys in order to provide shortcut keys of keyboard. Also, we develop recovery method which allows users go from camera and then come back again in order to eliminate neck fatigue effect. The experiments which involve several users have been done in our laboratory. The results show that the use of our camera mouse able to allow users do typing, left and right click events, drag and drop events, and troubleshooting without hand. By implement this system, handicap person can use computer more comfortable and reduce the dryness of eyes.
A Proposed Web Accessibility Framework for the Arab DisabledWaqas Tariq
The Web is providing unprecedented access to information and interaction for people with disabilities. This paper presents a Web accessibility framework which offers the ease of the Web accessing for the disabled Arab users and facilitates their lifelong learning as well. The proposed framework system provides the disabled Arab user with an easy means of access using their mother language so they don’t have to overcome the barrier of learning the target-spoken language. This framework is based on analyzing the web page meta-language, extracting its content and reformulating it in a suitable format for the disabled users. The basic objective of this framework is supporting the equal rights of the Arab disabled people for their access to the education and training with non disabled people. Key Words : Arabic Moon code, Arabic Sign Language, Deaf, Deaf-blind, E-learning Interactivity, Moon code, Web accessibility , Web framework , Web System, WWW.
Real Time Blinking Detection Based on Gabor FilterWaqas Tariq
New method of blinking detection is proposed. The utmost important of blinking detections method is robust against different users, noise, and also change of eye shape. In this paper, we propose blinking detections method by measuring of distance between two arcs of eye (upper part and lower part). We detect eye arcs by apply Gabor filter onto eye image. As we know that Gabor filter has advantage on image processing application since it able to extract spatial localized spectral features, such line, arch, and other shape are more easily detected. After two of eye arcs are detected, we measure the distance between both by using connected labeling method. The open eye is marked by the distance between two arcs is more than threshold and otherwise, the closed eye is marked by the distance less than threshold. The experiment result shows that our proposed method robust enough against different users, noise, and eye shape changes with perfectly accuracy.
Computer Input with Human Eyes-Only Using Two Purkinje Images Which Works in ...Waqas Tariq
A method for computer input with human eyes-only using two Purkinje images which works in a real time basis without calibration is proposed. Experimental results shows that cornea curvature can be estimated by using two light sources derived Purkinje images so that no calibration for reducing person-to-person difference of cornea curvature. It is found that the proposed system allows usersf movements of 30 degrees in roll direction and 15 degrees in pitch direction utilizing detected face attitude which is derived from the face plane consisting three feature points on the face, two eyes and nose or mouth. Also it is found that the proposed system does work in a real time basis.
Toward a More Robust Usability concept with Perceived Enjoyment in the contex...Waqas Tariq
Mobile multimedia service is relatively new but has quickly dominated people¡¯s lives, especially among young people. To explain this popularity, this study applies and modifies the Technology Acceptance Model (TAM) to propose a research model and conduct an empirical study. The goal of study is to examine the role of Perceived Enjoyment (PE) and what determinants can contribute to PE in the context of using mobile multimedia service. The result indicates that PE is influencing on Perceived Usefulness (PU) and Perceived Ease of Use (PEOU) and directly Behavior Intention (BI). Aesthetics and flow are key determinants to explain Perceived Enjoyment (PE) in mobile multimedia usage.
Collaborative Learning of Organisational KnolwedgeWaqas Tariq
This paper presents recent research into methods used in Australian Indigenous Knowledge sharing and looks at how these can support the creation of suitable collaborative envi- ronments for timely organisational learning. The protocols and practices as used today and in the past by Indigenous communities are presented and discussed in relation to their relevance to a personalised system of knowledge sharing in modern organisational cultures. This research focuses on user models, knowledge acquisition and integration of data for constructivist learning in a networked repository of or- ganisational knowledge. The data collected in the repository is searched to provide collections of up-to-date and relevant material for training in a work environment. The aim is to improve knowledge collection and sharing in a team envi- ronment. This knowledge can then be collated into a story or workflow that represents the present knowledge in the organisation.
Our research aims to propose a global approach for specification, design and verification of context awareness Human Computer Interface (HCI). This is a Model Based Design approach (MBD). This methodology describes the ubiquitous environment by ontologies. OWL is the standard used for this purpose. The specification and modeling of Human-Computer Interaction are based on Petri nets (PN). This raises the question of representation of Petri nets with XML. We use for this purpose, the standard of modeling PNML. In this paper, we propose an extension of this standard for specification, generation and verification of HCI. This extension is a methodological approach for the construction of PNML with Petri nets. The design principle uses the concept of composition of elementary structures of Petri nets as PNML Modular. The objective is to obtain a valid interface through verification of properties of elementary Petri nets represented with PNML.
Development of Sign Signal Translation System Based on Altera’s FPGA DE2 BoardWaqas Tariq
The main aim of this paper is to build a system that is capable of detecting and recognizing the hand gesture in an image captured by using a camera. The system is built based on Altera’s FPGA DE2 board, which contains a Nios II soft core processor. Image processing techniques and a simple but effective algorithm are implemented to achieve this purpose. Image processing techniques are used to smooth the image in order to ease the subsequent processes in translating the hand sign signal. The algorithm is built for translating the numerical hand sign signal and the result are displayed on the seven segment display. Altera’s Quartus II, SOPC Builder and Nios II EDS software are used to construct the system. By using SOPC Builder, the related components on the DE2 board can be interconnected easily and orderly compared to traditional method that requires lengthy source code and time consuming. Quartus II is used to compile and download the design to the DE2 board. Then, under Nios II EDS, C programming language is used to code the hand sign translation algorithm. Being able to recognize the hand sign signal from images can helps human in controlling a robot and other applications which require only a simple set of instructions provided a CMOS sensor is included in the system.
An overview on Advanced Research Works on Brain-Computer InterfaceWaqas Tariq
A brain–computer interface (BCI) is a proficient result in the research field of human- computer synergy, where direct articulation between brain and an external device occurs resulting in augmenting, assisting and repairing human cognitive. Advanced works like generating brain-computer interface switch technologies for intermittent (or asynchronous) control in natural environments or developing brain-computer interface by Fuzzy logic Systems or by implementing wavelet theory to drive its efficacies are still going on and some useful results has also been found out. The requirements to develop this brain machine interface is also growing day by day i.e. like neuropsychological rehabilitation, emotion control, etc. An overview on the control theory and some advanced works on the field of brain machine interface are shown in this paper.
Exploring the Relationship Between Mobile Phone and Senior Citizens: A Malays...Waqas Tariq
There is growing ageing phenomena with the rise of ageing population throughout the world. According to the World Health Organization (2002), the growing ageing population indicates 694 million, or 223% is expected for people aged 60 and over, since 1970 and 2025.The growth is especially significant in some advanced countries such as North America, Japan, Italy, Germany, United Kingdom and so forth. This growing older adult population has significantly impact the social-culture, lifestyle, healthcare system, economy, infrastructure and government policy of a nation. However, there are limited research studies on the perception and usage of a mobile phone and its service for senior citizens in a developing nation like Malaysia. This paper explores the relationship between mobile phones and senior citizens in Malaysia from the perspective of a developing country. We conducted an exploratory study using contextual interviews with 5 senior citizens of how they perceive their mobile phones. This paper reveals 4 interesting themes from this preliminary study, in addition to the findings of the desirable mobile requirements for local senior citizens with respect of health, safety and communication purposes. The findings of this study bring interesting insight to local telecommunication industries as a whole, and will also serve as groundwork for more in-depth study in the future.
Principles of Good Screen Design in WebsitesWaqas Tariq
Visual techniques for proper arrangement of the elements on the user screen have helped the designers to make the screen look good and attractive. Several visual techniques emphasize the arrangement and ordering of the screen elements based on particular criteria for best appearance of the screen. This paper investigates few significant visual techniques in various web user interfaces and showcases the results for better understanding and their presence.
Virtual teams are used more and more by companies and other organizations to receive benefits. They are a great way to enable teamwork in situations where people are not sitting in the same physical place at the same time. As companies seek to increase the use of virtual teams, a need exists to explore the context of these teams, the virtuality of a team and software that may help these teams working virtualy. Virtual teams have the same basic principles as traditional teams, but there is one big difference. This difference is the way the team members communicate. Instead of using the dynamics of in-office face-to-face exchange, they now rely on special communication channels enabled by modern technologies, such as e-mails, faxes, phone calls and teleconferences, virtual meetings etc. This is why this paper is focused on the issues regarding virtual teams, and how these teams are created and progressing in Albania.
Cognitive Approach Towards the Maintenance of Web-Sites Through Quality Evalu...Waqas Tariq
It is a well established fact that the Web-Applications require frequent maintenance because of cutting– edge business competitions. The authors have worked on quality evaluation of web-site of Indian ecommerce domain. As a result of that work they have made a quality-wise ranking of these sites. According to their work and also the survey done by various other groups Futurebazaar web-site is considered to be one of the best Indian e-shopping sites. In this research paper the authors are assessing the maintenance of the same site by incorporating the problems incurred during this evaluation. This exercise gives a real world maintainability problem of web-sites. This work will give a clear picture of all the quality metrics which are directly or indirectly related with the maintainability of the web-site.
USEFul: A Framework to Mainstream Web Site Usability through Automated Evalua...Waqas Tariq
A paradox has been observed whereby web site usability is proven to be an essential element in a web site, yet at the same time there exist an abundance of web pages with poor usability. This discrepancy is the result of limitations that are currently preventing web developers in the commercial sector from producing usable web sites. In this paper we propose a framework whose objective is to alleviate this problem by automating certain aspects of the usability evaluation process. Mainstreaming comes as a result of automation, therefore enabling a non-expert in the field of usability to conduct the evaluation. This results in reducing the costs associated with such evaluation. Additionally, the framework allows the flexibility of adding, modifying or deleting guidelines without altering the code that references them since the guidelines and the code are two separate components. A comparison of the evaluation results carried out using the framework against published evaluations of web sites carried out by web site usability professionals reveals that the framework is able to automatically identify the majority of usability violations. Due to the consistency with which it evaluates, it identified additional guideline-related violations that were not identified by the human evaluators.
Robot Arm Utilized Having Meal Support System Based on Computer Input by Huma...Waqas Tariq
A robot arm utilized having meal support system based on computer input by human eyes only is proposed. The proposed system is developed for handicap/disabled persons as well as elderly persons and tested with able persons with several shapes and size of eyes under a variety of illumination conditions. The test results with normal persons show the proposed system does work well for selection of the desired foods and for retrieve the foods as appropriate as usersf requirements. It is found that the proposed system is 21% much faster than the manually controlled robotics.
Dynamic Construction of Telugu Speech Corpus for Voice Enabled Text EditorWaqas Tariq
In recent decades speech interactive systems have gained increasing importance. Performance of an ASR system mainly depends on the availability of large corpus of speech. The conventional method of building a large vocabulary speech recognizer for any language uses a top-down approach to speech. This approach requires large speech corpus with sentence or phoneme level transcription of the speech utterances. The transcriptions must also include different speech order so that the recognizer can build models for all the sounds present. But, for Telugu language, because of its complex nature, a very large, well annotated speech database is very difficult to build. It is very difficult, if not impossible, to cover all the words of any Indian language, where each word may have thousands and millions of word forms. A significant part of grammar that is handled by syntax in English (and other similar languages) is handled within morphology in Telugu. Phrases including several words (that is, tokens) in English would be mapped on to a single word in Telugu.Telugu language is phonetic in nature in addition to rich in morphology. That is why the speech technology developed for English cannot be applied to Telugu language. This paper highlights the work carried out in an attempt to build a voice enabled text editor with capability of automatic term suggestion. Main claim of the paper is the recognition enhancement process developed by us for suitability of highly inflecting, rich morphological languages. This method results in increased speech recognition accuracy with very much reduction in corpus size. It also adapts Telugu words to the database dynamically, resulting in growth of the corpus.
An Improved Approach for Word Ambiguity RemovalWaqas Tariq
Word ambiguity removal is a task of removing ambiguity from a word, i.e. correct sense of word is identified from ambiguous sentences. This paper describes a model that uses Part of Speech tagger and three categories for word sense disambiguation (WSD). Human Computer Interaction is very needful to improve interactions between users and computers. For this, the Supervised and Unsupervised methods are combined. The WSD algorithm is used to find the efficient and accurate sense of a word based on domain information. The accuracy of this work is evaluated with the aim of finding best suitable domain of word. Keywords: Human Computer Interaction, Supervised Training, Unsupervised Learning, Word Ambiguity, Word sense disambiguation
Parameters Optimization for Improving ASR Performance in Adverse Real World N...Waqas Tariq
From the existing research it has been observed that many techniques and methodologies are available for performing every step of Automatic Speech Recognition (ASR) system, but the performance (Minimization of Word Error Recognition-WER and Maximization of Word Accuracy Rate- WAR) of the methodology is not dependent on the only technique applied in that method. The research work indicates that, performance mainly depends on the category of the noise, the level of the noise and the variable size of the window, frame, frame overlap etc is considered in the existing methods. The main aim of the work presented in this paper is to use variable size of parameters like window size, frame size and frame overlap percentage to observe the performance of algorithms for various categories of noise with different levels and also train the system for all size of parameters and category of real world noisy environment to improve the performance of the speech recognition system. This paper presents the results of Signal-to-Noise Ratio (SNR) and Accuracy test by applying variable size of parameters. It is observed that, it is really very hard to evaluate test results and decide parameter size for ASR performance improvement for its resultant optimization. Hence, this study further suggests the feasible and optimum parameter size using Fuzzy Inference System (FIS) for enhancing resultant accuracy in adverse real world noisy environmental conditions. This work will be helpful to give discriminative training of ubiquitous ASR system for better Human Computer Interaction (HCI). Keywords: ASR Performance, ASR Parameters Optimization, Multi-Environmental Training, Fuzzy Inference System for ASR, ubiquitous ASR system, Human Computer Interaction (HCI)
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Design Artificial Nonlinear Robust Controller Based on CTLC and FSMC with Tunable Gain
1. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 195
Design Artificial Nonlinear Robust Controller Based on CTLC and
FSMC With Tunable Gain
Farzin Piltan SSP.ROBOTIC@yahoo.com
Department of Electrical and Electronic
Engineering, Faculty of Engineering,Universiti
Putra Malaysia 43400 Serdang, Selangor, Malaysia
N. Sulaiman nasri@eng.upm.edu.my
Department of Electrical and Electronic
Engineering, Faculty of Engineering,Universiti
Putra Malaysia 43400 Serdang, Selangor, Malaysia
Zahra Tajpaykar SSP.ROBOTIC@yahoo.com
Industrial Electrical and Electronic Engineering
SanatkadeheSabze Pasargad. CO (S.S.P.
Co),NO:16 , PO.Code 71347-66773, Fourth floor
Dena Apr , Seven Tir Ave , Shiraz , Iran
Payman Ferdosali SSP.ROBOTIC@yahoo.com
Industrial Electrical and Electronic Engineering
SanatkadeheSabze Pasargad. CO (S.S.P.
Co),NO:16 , PO.Code 71347-66773, Fourth floor
Dena Apr , Seven Tir Ave , Shiraz , Iran
Mehdi Rashidi SSP.ROBOTIC@yahoo.com
Industrial Electrical and Electronic Engineering
SanatkadeheSabze Pasargad. CO (S.S.P.
Co),NO:16 , PO.Code 71347-66773, Fourth floor
Dena Apr , Seven Tir Ave , Shiraz , Iran
Abstract
One of the most active research areas in the field of robotics is robot manipulators control, because these
systems are multi-input multi-output (MIMO), nonlinear, time variant and uncertainty. An artificial non linear
robust controller design is major subject in this work. At present, robot manipulators are used in unknown
and unstructured situation and caused to provide complicated systems, consequently nonlinear classical
controllers are used in artificial intelligence control methodologies to design nonlinear robust controller with
satisfactory performance (e.g., minimum error, good trajectory, disturbance rejection). Sliding mode
controller (SMC) and computed torque controller (CTC) are the best nonlinear robust controllers which can
be used in uncertainty nonlinear. Sliding mode controller has two most important challenges in uncertain
systems: chattering phenomenon and nonlinear dynamic equivalent part. Computed torque controller
works very well when all nonlinear dynamic parameters are known. This research is focused on the
applied non-classical method (e.g., Fuzzy Logic) in robust classical method (e.g., Sliding Mode Controller
and computed torque controller) in the presence of uncertainties and external disturbance to reduce the
limitations. Applying the Mamdani’s error based fuzzy logic controller with minimum rules is the first goal
that causes the elimination of the mathematical nonlinear dynamic in SMC and CTC. Second target
focuses on the elimination of chattering phenomenon with regard to the variety of uncertainty and external
disturbance in fuzzy sliding mode controller and computed torque like controller by optimization the tunable
gain. Therefore fuzzy sliding mode controller with tunable gain (GTFSMC) and computed torque like
controller with tunable gain (GTCTLC) will be presented in this paper.
2. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 196
Keywords: robot manipulator, nonlinear robust controller, classical controller, minimum error,
good trajectory, disturbance rejection, sliding mode controller, computed torque controller, fuzzy
sliding mode controller, computed torque like controller and tunable gain.
1. INTRODUCTION
A robot system without any controllers does not to have any benefits, because controller is the main part in
this sophisticated system. The main objectives to control robot manipulators are stability and robustness.
Many researchers work on designing the controller for robotic manipulators in order to have the best
performance. Control of any systems divided in two main groups: linear and nonlinear controller [1].
Most of robot manipulators which work in industry are usually controlled by linear PID controllers. But the
robot manipulator dynamic functions are, nonlinear with strong coupling between joints (low gear ratio),
structure and unstructured uncertainty, and multi- inputs multi-outputs (MIMO) which, design linear
controller is very difficult especially if the velocity and acceleration of robot manipulator be high and also
when the ratio between joints gear be small [2]. To eliminate above problems in physical systems most of
control researcher go toward to select nonlinear robust controller.
One of the most important powerful nonlinear robust controllers is sliding mode controller (SMC). Sliding
mode control methodology was first proposed in the 1950 [3]. This controller has been analyzed by many
researchers in recent years. The main reason to opt for this controller is its acceptable control performance
wide range and solves some main challenging topics in control such as resistivity to the external
disturbance and uncertainty. However pure sliding mode controller has some disadvantages. First,
chattering problem can caused the high frequency oscillation of the controllers output [16-23]. Equivalent
dynamic formulation is another disadvantage where calculation of equivalent control formulation is difficult
since it is depending on the nonlinear dynamic equation [6-11].
Computed torque controller (CTC) is a powerful nonlinear controller which it widely used in control robot
manipulator. It is based on Feed-back linearization and computes the required arm torques using the
nonlinear Feed-back control law. This controller works very well when all dynamic and physical parameters
are known but when the robot manipulator has variation in dynamic parameters, in this situation the
controller has no acceptable performance[32-34]. In practice, most of physical systems (e.g., robot
manipulators) parameters are unknown or time variant, therefore, computed torque like controller used to
compensate dynamic equation of robot manipulator[1,3]. Research on computed torque controller is
significantly growing on robot manipulator application which has been reported in [1,3, 32-34].
Some researchers had applied fuzzy logic methodology [4-5] in sliding mode controllers (FSMC) in order to
reduce the chattering and to solve the nonlinear dynamic equivalent problems in pure sliding mode
controller [6-11, 16-23] and the other researchers applied fuzzy logic methodology in computed torque
controller (CTLC) in order to eliminate the nonlinear part in pure computed torque controller. [32-34]
This paper is organized as follows: In section 2, main subject of modelling robot manipulator formulation
are presented. This section covers the following details, introducing the dynamic formulation of robot
manipulator. In section 3, the main subject of sliding mode controller and formulation are presented. Detail
of computed torque controller is presented in section 4. The main subject of designing fuzzy sliding mode
controller with tuneable gain and computed torque like controller with tuneable gain are presented in
section 5. This section covers the self tuning proposed fuzzy sliding mode controller and self tuning
computed torque like controller. This method is used to reduce the chattering and estimate the equivalent
(nonlinear) part in both controllers. In section 6, the simulation result is presented and finally in section 7,
the conclusion is presented.
2. ROBOTIC MANIPULATOR FORMULATION
Dynamic modelling of robot manipulators is used to describe the behaviour of robot manipulator, design of
model based controller, and simulation results. The dynamic modelling describe the relationship between
joint motion, velocity, and accelerations to force/torque or current/voltage and also it can be used to
describe the particular dynamic effects (e.g., inertia, coriolios, centrifugal, and the other parameters) to
3. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 197
behaviour of system. It is well known that the equation of an n-DOF robot manipulator governed by the
following equation [1,3, 13-15]:
ࡹሺሻሷ ࡺሺ, ሶ ሻ ൌ ࣎ (1)
Where τ is actuation torque, ࡹሺ) is a symmetric and positive define inertia matrix, ࡺሺ, ሶ ሻ is the vector of
nonlinearity term. This robot manipulator dynamic equation can also be written in a following form [12, 35]:
࣎ ൌ ࡹሺሻሷ ሺሻሾሶ ሶ ሿ ሺሻሾሶ ሿ
ࡳሺሻ (2)
Where ሺሻ is the matrix of coriolios torques, ሺሻ is the matrix of centrifugal torques, and ࡳሺሻ is the
vector of gravity force. The dynamic terms in equation (2) are only manipulator position. This is a
decoupled system with simple second order linear differential dynamics. In other words, the component ݍሷ
influences, with a double integrator relationship, only the joint variableݍ, independently of the motion of the
other joints. Therefore, the angular acceleration is found as to be [1]:
ሷ ൌ ࡹିሺሻ. ሼ࣎ െ ࡺሺ, ሶ ሻሽ (3)
3. CLASSICAL SLIDING MODE CONTROLLER
Basically formulation of a sliding mode controller is [3]:
ࢁ ൌ ࢁࢋ ࢁࢊ࢙ (4)
Where, the model-based component ࢁࢋ compensate for the nominal dynamics of the systems. So ࢁࢋ
can be calculated as follows [1, 3]:
ࢁࢋ ൌ ൣࡹିሺ ࡳሻ ࡿሶ ൧ࡹ (5)
Suppose that ࡿ ൌ ࣅࢋ ࢋሶ therefore ࡿሶ ൌ ࣅࢋሶ ሷ ࢊ.
A simple solution to get the sliding condition when the dynamic parameters have uncertainty is the
switching control law:
ࢁࢊ࢙ ൌ ࡷሺ࢞ሬሬԦ, ࢚ሻ. ࢙ࢍሺ࢙ሻ ࢙ࢍሺ࢙ሻ ൌ ൝
࢙ 0
െ ࢙ ൏ 0
࢙ ൌ
(6)
Where the ࡷሺ࢞ሬሬԦ, ࢚ሻ is the positive constant. To reduce chattering many researchers introduced the
boundary layer methods, which in this method the basic idea is to replace the discontinuous method by
saturation (linear) method with small neighbourhood of the switching surface. Therefore the saturation
function ࡿࢇ࢚ሺࡿ
ൗ ሻ added to the control law:
ࢁ ൌ ࡷሺ࢞ሬሬԦ, ࢚ሻ. ࡿࢇ࢚ ቀࡿ
ൗ ቁ ࢙ࢇ࢚ ቀࡿ
ൗ ቁ ൌ
ە
۔
ۓ
ሺ࢙
ൗ 1ሻ
െ ሺ࢙
ൗ ൏ 1ሻ
ࡿ
ൗ ሺെ ൏ ࢙
ൗ ൏ 1ሻ
(7)
where is the width of the boundary layer, therefore the control output can be write as
ࢁ ൌ ࢁࢋ ࡷ. ࢙ࢇ࢚ ቀࡿ
ൗ ቁ ൌ ൝
ࢁࢋ ࡷ. ࢙ࢍሺࡿሻ , |ࡿ|
ࢁࢋ ࡷ. ࡿ
ൗ , |ࡿ| ൏
(8)
Figure 1 shows the block diagram of classical sliding mode controller.
4. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 198
4. COMPUTED TORQUE CONTROLLER
The central idea of Computed torque controller (CTC) is feedback linearization so, originally this algorithm
is called feedback linearization controller. It is assumed that the desired motion trajectory for the
manipulator ࢊሺ࢚ሻ, as determined, by a path planner. Define the tracking error as:
ࢋሺ࢚ሻ ൌ ࢊሺ࢚ሻ െ ࢇሺ࢚ሻ (9)
Where e(t) is error of the plant, ࢊሺ࢚ሻ is desired input variable, that in our system is desired displacement,
ࢇሺ࢚ሻ is actual displacement. If an alternative linear state-space equation in the form ࢞ሶ ൌ ࢞ ࢁ can be
defined as
࢞ሶ ൌ ቂ
ࡵ
ቃ ࢞ ቂ
ࡵ
ቃ ࢁ (10)
With ࢁ ൌ െࡹିሺሻ. ࡺሺ, ሶ ሻ ࡹିሺሻ. ࣎ and this is known as the Brunousky canonical form. By equation
(4) and (5) the Brunousky canonical form can be written in terms of the state ࢞ ൌ ሾࢋࢀ
ࢋሶࢀ
ሿࢀ
as:
ࢊ
ࢊ࢚
ቂ
ࢋ
ࢋሶ
ቃ ൌ ቂ
ࡵ
ቃ . ቂ
ࢋ
ࢋሶ
ቃ ቂ
ࡵ
ቃ ࢁ
(11)
With ܃ ൌ ܙሷ ܌ ۻିሺܙሻ. ሼۼሺ.ܙ ܙሶ ሻ െ ૌሽ (12)
Then compute the required arm torques using inverse of equation (12), namely, [1, 3, 6, 12]
࣎ ൌ ࡹሺሻሺࢊሷ െ ࢁሻ ࡺሺሶ , ሻ (13)
This is a nonlinear feedback control law that guarantees tracking of desired trajectory. Selecting
proportional-plus-derivative (PD) feedback for U(t) results in the PD-computed torque controller[3];
࣎ ൌ ࡹሺሻ൫ሷ ࢊ ࡷ࢜ࢋሶ ࡷࢋ൯ ࡺሺ, ሶ ሻ (14)
and the resulting linear error dynamics are
൫ሷ ࢊ ࡷ࢜ࢋሶ ࡷࢋ൯ ൌ (15)
According to linear system theory, convergence of the tracking error to zero is guaranteed [2].
FIGURE 1 : Block diagram of classical sliding mode controller
5. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 199
Where ࡷ and ࡷ࢜ are the controller gains.
The resulting schemes is shown in Figure 2, in which two feedback loops, namely, inner loop and outer
loop, which an inner loop is a compensate loop and an outer loop is a tracking error loop. However, mostly
parameter ࡺሺ, ሶ ሻ is all unknown. So the control cannot be implementation because non linear parameters
cannot be determined. In the following section computed torque like controller will be introduced to
overcome the problems.
5. FUZZY LOGIC AND ITS APPLICATION TO SLIDING MODE CONTROLLER
(FSMC) AND COMPUTED TORQUE CONTROLLER (CTLC)
To compensate the nonlinearity for dynamic equivalent control several researchers used model base fuzzy
controller instead of classical equivalent controller that was employed to obtain the desired control
behaviour and a fuzzy switching control was applied to reinforce system performance. In the proposed
fuzzy sliding mode control fuzzy rule base was designed to estimate the dynamic equivalent part [24-31]. A
block diagram for proposed fuzzy sliding mode controller is shown in Figure 3. In this method fuzzy rule for
sliding surface (S) to design fuzzy error base-like equivalent control was obtained the rules where used
instead of nonlinear dynamic equation of equivalent control to reduce the chattering and also to eliminate
the nonlinear formulation of dynamic equivalent control term.
݂݅ ܵ ݅ݏ ܰܤ ݄݊݁ݐ ߬ ݅ݏ ܰܤ
݂݅ ܵ ݅ݏ ܼ ݄݊݁ݐ ߬ ݅ݏ ܼ
(16)
FIGURE 2 : Block diagram of PD-computed torque controller (PD-CTC)
6. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 200
In FSMC the tracking error is defined as:
ࢋ ൌ ࢊ െ ࢇ (17)
where ࢊ ൌ ሾࢊ, ࢊ, ࢊሿࢀ
is desired output and ࢇ ൌ ሾࢇ, ࢇ, ࢇሿࢀ
is an actual output. The
sliding surface is defined as follows:
ࡿ ൌ ࢋሶ ࣅࢋ (18)
where ࣅ ൌ ࢊࢇࢍሾࣅ, ࣅ, ࣅሿ is chosen as the bandwidth of the robot manipulator controller. The time
derivative of S can be calculated by the following equation
ࡿሶ ൌ ሷ ࢊ ࣅࢋሶ
Based on classical SMC the FSMC can be calculated as
(19)
࣎ො ൌ ࣎ࢌ࢛ࢠࢠ࢟ ࢙࣎ࢇ࢚ (20)
Where, the model-based component ࣎ොࢋ compensate for the nominal dynamics of systems. So ࣎ොࢋ can be
calculated as
࣎ࢌ࢛ࢠࢠ࢟ ൌ ൣࡹିሺ ࡳሻ ࡿሶ൧ࡹ (21)
and ࢙࣎ࢇ࢚ is
࢙࣎ࢇ࢚ ൌ ࡷ. ࢙ࢇ࢚ሺࡿሻ (22)
As a summary the design of fuzzy logic controller for FSMC has five steps:
1. Determine inputs and outputs: This controller has one input ሺܵሻ and one output (߬௨௭௭௬).
The input is sliding surface ሺܵሻ and the output is torque൫߬௨௭௭௬൯.
2. Find membership function and linguistic variable: The linguistic variables for
sliding surface ሺܵሻ are; Negative Big (NB), Negative Medium (NM), Negative Small (NS), Zero (Z),
Positive Small (PS), Positive Medium (PM), Positive Big (PB), and it is quantized into thirteen
levels represented by: -1, -0.83, -0.66, -0.5, -0.33, -0.16, 0, 0.16, 0.33, 0.5, 0.66, 0.83, 1, and the
FIGURE 3 : Block diagram of proposed FSMC with minimum rule base
7. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 201
linguistic variables to find the torque ൫߬௨௭௭௬൯ are; Large Left (LL), Medium Left (ML), Small Left
(SL), Zero (Z), Small Right (SR), Medium Right (MR), Large Right (LR) and it is quantized in to
thirteen levels represented by: -85, -70.8, -56.7, -42.5, -28.3, -14.2, 0, 14.2, 28.3, 42.5, 56.7, 70.8,
85.
3. Choice of shape of membership function: In this work triangular membership function
was selected as shown in Figure 4.
4. Design fuzzy rule table: design the rule base of fuzzy logic controller can play important
role to design best performance SMFC, suppose that two fuzzy rules in this controller are
F.R1
: IF S is Z, THEN ࣎ is Z.
F.R2
: IF e is (PB) THEN ࣎ is (LR).
(23)
The complete rule base for this controller is shown in Table 1.
ࡿ NB NM NS Z PS PM PB
࣎ LL ML SL Z SR MR LR
TABLE 1: Rule table for proposed FSMC
The control strategy that deduced by table.1 are
If sliding surface (S) is N.B, the control applied is N.B for moving S to S=0.
If sliding surface (S) is Z, the control applied is Z for moving S to S=0.
5. Defuzzification: The final step to design fuzzy logic controller is deffuzification , there are
many deffuzzification methods in the literature, in this controller the COG method will be used,
where this is given by
ࡻࡳሺ࢞, ࢟ሻ ൌ
∑ ࢁ ∑ . ࣆ࢛ሺ࢞, ࢟, ࢁሻ࢘
ୀ
∑ ∑ . ࣆ࢛ሺ࢞, ࢟, ࢁሻ࢘
ୀ
(24)
As mention previously, computed torque like controller (CTLC) is fuzzy controller based on computed
torque method for easy implementation, stability, and robustness. The main drawback of CTLC is the value
of gain updating factor ࡷ ࢇࢊ ࡷ࢜ must be pri-defined very carefully and the most important advantage of
FIGURE 4 : Membership function: a) sliding surface b) torque
8. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 202
CTLC compare to pure CTC is a nonlinearity dynamic parameter. It is basic that the system performance is
sensitive to the gain updating factors for both computed torque controller and computed torque like
controller application. For instance, if large value of ࡷࢂ is chosen the response is very fast but the system
is very unstable and conversely, if small value of ࡷࢂ considered the response of system is very slow but
the system is very stable. Therefore, calculate the optimum value of gain updating factors for a system is
one of the most important challenging works. However most of time the control performance for FLC and
CTLC is similar to each other, but CTLC has two most important advantages:
The number of rule base is smaller
Increase the robustness and stability
In this method the control output can be calculated by
ૌ ൌ ૌො ૌܡܢܢܝሺ܁ሻ (25)
Where ࣎ෝthe nominal compensation is term and ࣎ࢌ࢛ࢠࢠ࢟ሺ࢙ሻ is the output of computed torque fuzzy controller.
The most important target in computed torque like controller (CTLC) is design computed torque control
combined to fuzzy logic systems to solve the problems in classical computed torque controller. To
compensate the nonlinearity of nonlinear dynamic part several researchers used model base fuzzy
controller instead of classical nonlinear dynamic part that was employed to obtain the desired control
behaviour and a fuzzy switching control was applied to reinforce system performance. In proposed fuzzy
computed torque controller the author design fuzzy rule base to estimate the dynamic nonlinear part. A
block diagram for proposed fuzzy computed controller is shown in Figure 5.
The sliding surface is defined as follows:
ࡸ ൌ ࡹሺሻ൫ሷ ࢊ ࡷ࢜ࢋሶ ࡷࢋ൯ (26)
Based on classical computed torque controller for a multi DOF robot manipulator:
࣎ො ൌ ࣎ොࢋࢇ࢘ ࣎ (27)
where, the model-based component ߬̂ compensate for the nominal dynamics of systems. So
߬̂ can calculate as follows:
࣎ොࢋࢇ࢘ ൌ ሺሻሶ ሶ ሺሻሶ
ࢍሺሻ (28)
and ࣎ can calculate as follows:
FIGURE 5 : Block diagram of proposed fuzzy computed torque controller with minimum rule base
9. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 203
࣎ ൌ ࡹሺሻ൫ሷ ࢊ ࡷ࢜ࢋሶ ࡷࢋ൯ (29)
In proposed FSMC nonlinear control part replaced by Mamdani’s fuzzy inference term, therefore (27) can
be rewrite as the following equation
࣎ො ൌ ࣎ࢌ࢛ࢠࢠ࢟ ࣎ (30)
6. GAIN TUNING FUZZY SLIDING MODE CONTROLLER (GTFSMC) AND GAIN
TUNING COMPUTED TORQUE LIKE CONTROLLER (GTCTLC)
This section focuses on, self tuning gain updating factor for most important factor in FSMC, namely, sliding
surface slope (ࣅ) and in self tuning computed torque controller (GTCTLC) namely, nonlinear equivalent
part (nonlinear term of controller). The block diagram for this method is shown in Figure 6. In this controller
the actual sliding surface gain (ࣅ) is obtained by multiplying the sliding surface with gain updating
factorሺࢻሻ. The gain updating factorሺࢻሻ is calculated on-line by fuzzy dynamic model independent which
has sliding surface (S) as its inputs. The gain updating factor is independent of any dynamic model of
robotic manipulator parameters.
It is a basic fact that the system performance in CTLC is sensitive to gain updating factor, K. Thus,
determination of an optimum K value for a system is an important problem. If the system parameters are
unknown or uncertain, the problem becomes more highlighted. This problem is solved by adjusting the
proportional and derivative gain updating factor of the computed torque controller continuously in real-time.
In this way, the performance of the overall system is improved with respect to the classical computed
torque controller. Therefore this section focuses on, self tuning gain updating factor for two type most
important factor in CTLC, namely, proportional gain updating factor (ࡷࡼ) and derivative gain updating
factor (ࡷ࢜ ). Gain tuning-CTLC has strong resistance and solves the uncertainty problems. The block
diagram for this method is shown in Figure 7.
In this controller the actual gain updating factor (ࡷࢋ࢝) is obtained by multiplying the old gain updating
factor (ࡷࢊሻ with the output of supervisory fuzzy controllerሺࢻሻ. The output of fuzzy supervisory controller
ሺࢻሻ is calculated on-line by fuzzy dynamic model independent which has sliding surface (S) as inputs.. The
value of ࢻ is not longer than 1 but it calculated on-line from its rule base. The scale factor, Kv and Kp are
updated by equations (18) and (19),
ࡷ࢜
ࢋ࢝
ൌ ࡷ࢜
ࢊ
ൈ ࢻ (31)
ࡷ
ࢋ࢝
ൌ ࡷ
ࢊ
ൈ ࢻ (32)
FIGURE 6 : Block diagram of proposed gain tuning fuzzy sliding mode controller with minimum rule base in fuzzy
equivalent part and fuzzy supervisory.
10. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 204
6. Simulation Result
Computed torque controller (CTC), classical sliding mode control (SMC), fuzzy sliding mode control
(FSMC), gain tuning computed torque like controller (GTCTLC) and gain tuning fuzzy sliding mode
controller (GTFSMC) are implemented in Matlab/Simulink environment for 3 DOF robot manipulator.
Tracking performance, error, and robustness are compared.
Tracking performances: Figure 8, 9 and 10 shows tracking performance for first, second and third link
of robot manipulator with above controllers. By comparing step response trajectory without disturbance in
above controllers, it is found that the GTCLC and GTFSMC overshoot (1.32%) are lower than CTC and
SMC (6.44%), all of them have about the same rise time. Besides the Steady State and RMS error in
GTCTLC and GTFSMC (Steady State error =0 and RMS error=0) are fairly lower than CTC and SMC
(Steady State error ؆ െି
and RMS error=െ. ൈ ି
).
FIGURE 7: Block diagram of proposed gain tuning fuzzy computed torque like controller with minimum rule base
in fuzzy nonlinear part and fuzzy supervisory.
11. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 205
FIGURE 8 : first link step trajectory without disterbance
FIGURE 9: second link step trajectory without disterbance
12. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 206
Disturbance Rejection
Figure 11, 12 and 13 have shown the power disturbance elimination in above controllers. The main
targets in these controllers are disturbance rejection as well as the other responses. A band limited white
noise with predefined of 40% the power of input signal is applied to the step response. It found fairly
fluctuations in trajectory responses. As mentioned earlier, CTC and SMC works very well when all
parameters are known, this challenge plays important role to select the GTCTLC and GTFSMC as a based
robust controller in this research.
FIGURE 10 : Third link step trajectory without disterbance
FIGURE 11 : First link step trajectory with disturbance
13. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 207
Errors in the Model: Figure 14 shows the tracking error for CTC, GTCTLC, SMC, FSMC, and
GTFSMC. Equally, the proposed gain tuning computed torque like controller and proposed self tuning
fuzzy sliding mode controller are more robust to changes of dynamic robot manipulator parameters value.
7. CONCLUSION
Refer to the research, a position artificial intelligence controller with tunable gain (GTCTLC and GTFSMC)
design and application to robot manipulator has proposed in order to design high performance nonlinear
controller in the presence of uncertainties. Regarding to the positive points in computed torque controller,
FIGURE 12: Second link step trajectory with disturbance
FIGURE 13: Third link step trajectory with disturbance
14. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 208
sliding mode controller, fuzzy logic controller and tunable method, the performance has improved. Each
method by adding to the previous controller has covered negative points. The system performance in
computed torque controller, computed torque like controller, sliding mode controller and fuzzy sliding mode
controller are sensitive to the gain updating factor. Therefore, compute the optimum value of gain updating
factor for a system is the important challenge work. This problem has solved by adjusting gain updating
factor of GTCTLC and GTFSMC. In this way, the overall system performance has improved with respect to
the classical sliding mode controller and computed torque controller. This method solved chattering
phenomenon as well as mathematical nonlinear equivalent part by applied fuzzy supervisory method.
REFERENCES
[1] T. R. Kurfess, Robotics and automation handbook: CRC, 2005.
[2] K . Ogata, Modern control engineering: Prentice Hall, 2009.
[3] B. Siciliano and O. Khatib, Springer handbook of robotics: Springer-Verlag New York Inc, 2008.
[4] L. Reznik, Fuzzy controllers: Butterworth-Heinemann, 1997.
[5] S. Mohan and S. Bhanot, "Comparative study of some adaptive fuzzy algorithms for manipulator
control," International Journal of Computational Intelligence, vol. 3, pp. 303–311, 2006.
[6] O. Kaynak, "Guest editorial special section on computationally intelligent methodologies and
sliding-mode control," IEEE Transactions on Industrial Electronics, vol. 48, pp. 2-3, 2001.
[7] Shahnazi R., H. Shanechi, N. Pariz. "Position control of induction and servomotors: A novel
adaptive fuzzy PI sliding mode control". IEEE Conferences on power engineering, 2006, P.P. 1-9.
[8] Medhaffar H., N. Derbel, and T. Damak. "A decoupled fuzzy indirect adaptive sliding mode
controller with application to robot manipulator". Int. Journal on modeling, identification and control,
1(1), 23-29, 2006.
FIGURE 14: Errors in model
15. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 209
[9] Shahnazi R., H. Shanechi, N. Pariz. "Position control of induction and servomotors: A novel
adaptive fuzzy PI sliding mode control". IEEE Journals on energy conversions, 23(1), 138-147,
2008.
[10] Weng C. C., W. S. Yu. "Adaptive fuzzy sliding mode control for linear time-varying uncertain
systems". IEEE conference on fuzzy systems, 2008, P.P: 1483-1490.
[11] Yu Z. X. "Adaptive sliding mode-like fuzzy logic control for nonlinear systems". Journal of
communication and computer, 6(1), 53-60, 2009.
[12] Piltan, F., et al. "Design sliding mode controller for robot manipulator with artificial tunable gain".
Canaidian Journal of pure and applied science, 5 (2), 1573-1579, 2011.
[13] B. S. R. Armstrong, "Dynamics for robot control: friction modeling and ensuring excitation during
parameter identification," 1988.
[14] B. Armstrong, et al., "The explicit dynamic model and inertial parameters of the PUMA 560 arm,"
2002, pp. 510-518.
[15] P. I. Corke and B. Armstrong-Helouvry, "A search for consensus among model parameters
reported for the PUMA 560 robot," 2002, pp. 1608-1613.
[16] V. Utkin, "Variable structure systems with sliding modes," Automatic Control, IEEE Transactions
on, vol. 22, pp. 212-222, 2002.
[17] R. A. DeCarlo, et al., "Variable structure control of nonlinear multivariable systems: a tutorial,"
Proceedings of the IEEE, vol. 76, pp. 212-232, 2002.
[18] K. D. Young, et al., "A control engineer's guide to sliding mode control," 2002, pp. 1-14.
[19] C. C. Weng and W. S. Yu, "Adaptive fuzzy sliding mode control for linear time-varying uncertain
systems," 2008, pp. 1483-1490.
[20] M. Ertugrul and O. Kaynak, "Neuro sliding mode control of robotic manipulators," Mechatronics,
vol. 10, pp. 239-263, 2000.
[21] P. Kachroo and M. Tomizuka, "Chattering reduction and error convergence in the sliding-mode
control of a class of nonlinear systems," Automatic Control, IEEE Transactions on, vol. 41, pp.
1063-1068, 2002.
[22] Y. Li and Q. Xu, "Adaptive Sliding Mode Control With Perturbation Estimation and PID Sliding
Surface for Motion Tracking of a Piezo-Driven Micromanipulator," Control Systems Technology,
IEEE Transactions on, vol. 18, pp. 798-810, 2010.
[23] B. Wu, et al., "An integral variable structure controller with fuzzy tuning design for electro-hydraulic
driving Stewart platform," 2006, pp. 5-945.
[24] L. A. Zadeh, "Toward a theory of fuzzy information granulation and its centrality in human
reasoning and fuzzy logic," Fuzzy Sets and Systems, vol. 90, pp. 111-127, 1997.
[25] J. Zhou and P. Coiffet, "Fuzzy control of robots," 2002, pp. 1357-1364.
[26] S. Banerjee and P. Y. Woo, "Fuzzy logic control of robot manipulator," 2002, pp. 87-88.
[27] K. Kumbla, et al., "Soft computing for autonomous robotic systems," Computers and Electrical
Engineering, vol. 26, pp. 5-32, 2000.
16. Farzin Piltan, N. Sulaiman, Z.Tajpaykar, P.Ferdosali & M.Rashidi
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (3) : 2011 210
[28] C. C. Lee, "Fuzzy logic in control systems: fuzzy logic controller. I," IEEE Transactions on
systems, man and cybernetics, vol. 20, pp. 404-418, 1990.
[29] R. J. Wai, et al., "Implementation of artificial intelligent control in single-link flexible robot arm,"
2003, pp. 1270-1275.
[30] R. J. Wai and M. C. Lee, "Intelligent optimal control of single-link flexible robot arm," Industrial
Electronics, IEEE Transactions on, vol. 51, pp. 201-220, 2004.
[31] M. B. Menhaj and M. Rouhani, "A novel neuro-based model reference adaptive control for a two
link robot arm," 2002, pp. 47-52.
[32] D. Nguyen-Tuong, et al., "Computed torque control with nonparametric regression models," 2008,
[33] A. Vivas and V. Mosquera, "Predictive functional control of a PUMA robot," 2005.
[34] Piltan. F. et al., "Design Artificial of Robust Control of second Order System Based on Adaptive
Fuzzy Gain Scheduling" World Applied Science Journal, 13(5), 1085-1092, 2011.
[35] Piltan. F. et al., " Artificial Control of second Order System Based on AFGSMC" Austrailian
Journal of Basic and Applied Science, 5(6), 509-522, 2011.