Performance measurement and dynamic analysis of two dof robotic arm manipulatoreSAT Journals
Abstract Forward and inverse kinematic analysis of 2DOF robot is presented to predict singular configurations. Cosine function is used for servo motor simulation of kinematics and dynamics using Pro/Engineer. The significance of joint-2 for reducing internal singularities is highlighted. Performance analysis in terms of condition number, local conditioning index and mobility index is carried out for the manipulator. Dynamic analysis using Lagrangian’s and Newton’s Euler approach is worked out analytically using MATLAB and results are plotted for their comparison. Index Terms: Forward kinematics, Inverse Kinematics, Workspace boundary, Singularity, Dynamics
Dynamics and control of a robotic arm having four linksAmin A. Mohammed
Abstract The manipulator control is an important problem
in robotics. To work out this problem, a correct dynamic
model for the robot manipulator must be in hand. Hence, this
work first presents the dynamic model of an existing 4-DOF
robot manipulator based on the Euler–Lagrange principle,
utilizing the body Jacobian of each link and the generalized
inertia matrix. Furthermore, essential properties of the
dynamic model are analyzed for the purpose of control. Then,
a PID controller is designed to control the position of the
robot by decoupling the dynamic model. To achieve a good
performance, the differential evolution algorithm is used for
the selection of parameters of the PID controller. Feedback
linearization scheme is also utilized for the position and trajectory
tracking control of the manipulator. The obtained
results reveal that the PID control coupled with the differential
evolution algorithm and the feedback linearization
control enhance the performance of the robotic manipulator.
It is also found out that increasing masses of manipulator
links do not affect the performance of the PID position control,
but higher control torques are required in these cases.
Keywords Robot control · PID · Differential evolution ·
Feedback linearization
PID control dynamics of a robotic arm manipulator with two degrees of freedom.popochis
This paper presents a basic example of PID control applied to a robotic manipulator arm with two DOF (degrees of freedom), as well as the design of the dynamic model, explaining in detail each step so that in future work, we can increase the diculty level regardless of DOF of the robot. Also shown how to introduce the PID controller parameters to the equation of the dynamics of the robot, left as future work the implementation of a real-time control of these variables.
Sliding Mode Controller Design for Hybrid Synchronization of Hyperchaotic Che...ijcsa
This paper derives new results for the design of sliding mode controller for the hybrid synchronization of identical hyperchaotic Chen systems (Jia, Dai and Hui, 2010). The synchronizer results derived in this paper for the hybrid synchronization of identical hyperchaotic Chen systems are established using Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the sliding mode control method is very effective and convenient to achieve hybrid synchronization of the
identical hyperchaotic Chen systems. Numerical simulations are shown to illustrate and validate the hybrid synchronization schemes derived in this paper for the identical hyperchaotic Chen systems.
Using real interpolation method for adaptive identification of nonlinear inve...IJECEIAES
In this paper, we investigate the inverted pendulum system by using real interpolation method (RIM) algorithm. In the first stage, the mathematical model of the inverted pendulum system and the RIM algorithm are presented. After that, the identification of the inverted pendulum system by using the RIM algorithm is proposed. Finally, the comparison of the linear analytical model, RIM model, and nonlinear model is carried out. From the results, it is found that the inverted pendulum system by using RIM algorithm has simplicity, low computer source requirement, high accuracy and adaptiveness in the advantages.
Performance measurement and dynamic analysis of two dof robotic arm manipulatoreSAT Journals
Abstract Forward and inverse kinematic analysis of 2DOF robot is presented to predict singular configurations. Cosine function is used for servo motor simulation of kinematics and dynamics using Pro/Engineer. The significance of joint-2 for reducing internal singularities is highlighted. Performance analysis in terms of condition number, local conditioning index and mobility index is carried out for the manipulator. Dynamic analysis using Lagrangian’s and Newton’s Euler approach is worked out analytically using MATLAB and results are plotted for their comparison. Index Terms: Forward kinematics, Inverse Kinematics, Workspace boundary, Singularity, Dynamics
Dynamics and control of a robotic arm having four linksAmin A. Mohammed
Abstract The manipulator control is an important problem
in robotics. To work out this problem, a correct dynamic
model for the robot manipulator must be in hand. Hence, this
work first presents the dynamic model of an existing 4-DOF
robot manipulator based on the Euler–Lagrange principle,
utilizing the body Jacobian of each link and the generalized
inertia matrix. Furthermore, essential properties of the
dynamic model are analyzed for the purpose of control. Then,
a PID controller is designed to control the position of the
robot by decoupling the dynamic model. To achieve a good
performance, the differential evolution algorithm is used for
the selection of parameters of the PID controller. Feedback
linearization scheme is also utilized for the position and trajectory
tracking control of the manipulator. The obtained
results reveal that the PID control coupled with the differential
evolution algorithm and the feedback linearization
control enhance the performance of the robotic manipulator.
It is also found out that increasing masses of manipulator
links do not affect the performance of the PID position control,
but higher control torques are required in these cases.
Keywords Robot control · PID · Differential evolution ·
Feedback linearization
PID control dynamics of a robotic arm manipulator with two degrees of freedom.popochis
This paper presents a basic example of PID control applied to a robotic manipulator arm with two DOF (degrees of freedom), as well as the design of the dynamic model, explaining in detail each step so that in future work, we can increase the diculty level regardless of DOF of the robot. Also shown how to introduce the PID controller parameters to the equation of the dynamics of the robot, left as future work the implementation of a real-time control of these variables.
Sliding Mode Controller Design for Hybrid Synchronization of Hyperchaotic Che...ijcsa
This paper derives new results for the design of sliding mode controller for the hybrid synchronization of identical hyperchaotic Chen systems (Jia, Dai and Hui, 2010). The synchronizer results derived in this paper for the hybrid synchronization of identical hyperchaotic Chen systems are established using Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the sliding mode control method is very effective and convenient to achieve hybrid synchronization of the
identical hyperchaotic Chen systems. Numerical simulations are shown to illustrate and validate the hybrid synchronization schemes derived in this paper for the identical hyperchaotic Chen systems.
Using real interpolation method for adaptive identification of nonlinear inve...IJECEIAES
In this paper, we investigate the inverted pendulum system by using real interpolation method (RIM) algorithm. In the first stage, the mathematical model of the inverted pendulum system and the RIM algorithm are presented. After that, the identification of the inverted pendulum system by using the RIM algorithm is proposed. Finally, the comparison of the linear analytical model, RIM model, and nonlinear model is carried out. From the results, it is found that the inverted pendulum system by using RIM algorithm has simplicity, low computer source requirement, high accuracy and adaptiveness in the advantages.
This paper proposed a nonlinear robust control for spacecraft attitude based on passivity and
disturbance suppression vector. The spacecraft model was described using quaternion. The control law
introduced the suppression vector of external disturbances and had no information related to the system
parameters. The desired performance of spacecraft attitude control could be achieved using the designed
control law. And stability conditions of the nonlinear robust control for spacecraft attitude were given. The
stability could be proved by applying Lyapunov approach. The verification of the proposed attitude control
method was performed through a series of simulations. The numerical results showed the effectiveness of
the proposed control method in controlling the spacecraft attitude in the presence of external disturbances.
The main benefit of the proposed attitude control method does not need angular velocity measurement
and has its robustness against model uncertainties and external disturbances.
A Numerical Integration Scheme For The Dynamic Motion Of Rigid Bodies Using T...IJRES Journal
The dynamics of rigid bodies have been studied extensively. However, a certain class of time-integration schemes were not consistent since they added vectors not belonging to the same tangent space (so3), of the Lie group (SO3) of the Special Orthogonal transformations in E3. The work of Cardona[1,2], and later Makinen[3,4], highlighted this fact using the rotation vector as the main parameter in their derivations. Some other programs in multibody dynamics, such as the work of Haug[5], rely on the Euler parameters, instead of the rotation vector, as the main variable in their formulations. For this class of programs, different time-integration schemes could be used .This paper discusses one such a scheme. As an example of application, the spinning top was used in this paper. For such a problem, the approximate change of the potential energy was found to be an upper bound to the change in the actual total energy during a time step.
SLIDING MODE CONTROLLER DESIGN FOR GLOBAL CHAOS SYNCHRONIZATION OF COULLET SY...ijistjournal
This paper derives new results for the design of sliding mode controller for the global chaos synchronization of identical Coullet systems (1981). The synchronizer results derived in this paper for the complete chaos synchronization of identical hyperchaotic systems are established using sliding control theory and Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the sliding mode control method is very effective and convenient to achieve global chaos synchronization of the identical Coullet systems. Numerical simulations are shown to illustrate and validate the synchronization schemes derived in this paper for the identical Coullet systems.
Comparison of a triple inverted pendulum stabilization using optimal control ...Mustefa Jibril
In this paper, modelling design and analysis of a triple inverted pendulum have been done using
Matlab/Script toolbox. Since a triple inverted pendulum is highly nonlinear, strongly unstable
without using feedback control system. In this paper an optimal control method means a linear
quadratic regulator and pole placement controllers are used to stabilize the triple inverted
pendulum upside. The impulse response simulation of the open loop system shows us that the
pendulum is unstable. The comparison of the closed loop impulse response simulation of the
pendulum with LQR and pole placement controllers results that both controllers have stabilized
the system but the pendulum with LQR controllers have a high overshoot with long settling time
than the pendulum with pole placement controller. Finally the comparison results prove that the
pendulum with pole placement controller improve the stability of the system.
ANALYTICAL SOLUTIONS OF THE MODIFIED COULOMB POTENTIAL USING THE FACTORIZATIO...ijrap
We have solved exactly Schrödinger equation with modified Coulomb Potential under the framework of
factorization method. Energy levels and the corresponding wave functions in terms of associated Laquerre
function are also obtained. For further guide to interested readers we have computed the energy
eigenvalue for some selected elements for various values of n and l .
Asymptotic Stability of Quaternion-based Attitude Control System with Saturat...IJECEIAES
In the design of attitude control, rotational motion of the spacecraft is usually considered as a rotation of rigid body. Rotation matrix parameterization using quaternion can represent globally attitude of a rigid body rotational motions. However, the representation is not unique hence implies difficulties on the stability guarantee. This paper presents asymptotically stable analysis of a continuous scheme of quaternion-based control system that has saturation function. Simulations run show that the designed system applicable for a zero initial angular velocity case and a non-zero initial angular velocity case due to utilization of deadzone function as an element of the defined constraint in the stability analysis.
Vibration analysis and response characteristics of a half car model subjected...editorijrei
The displacement response of different masses of half car model. The analysis has been done for different car models also to see the dynamic response of the driver body coupled with the seat of a vehicle. It has been assumed the driver body is rigidly coupled with seat of the vehicle. The vehicle has been modeled for two D.O.F, in two D.O.F Half car model two motion (Pitch and Bounce) have been considered. The response of the vehicle has been obtained for different velocities and different amplitudes sinusoidal bump excitation.
Finite element modelling of nonlocal dynamic systems, Modal analysis of nonlocal dynamical systems, Dynamics of damped nonlocal systems, Numerical illustrations
SLIDING CONTROLLER DESIGN FOR THE GLOBAL CHAOS SYNCHRONIZATION OF IDENTICAL H...ijait
This paper establishes new results for the sliding controller design for the global chaos synchronization of identical hyperchaotic Yujun systems (2010). Hyperchaotic systems are chaotic nonlinear systems having more than one positive Lyapunov exponent. Because of the complex dynamics properties of hyperchaotic system such as high capacity, high security and high efficiency, they are very useful in secure
communication devices and data encryption. Using sliding mode control theory and Lyapunov stability theory, a general result has been obtained for the global chaos synchronization of identical chaotic nonlinear systems. As an application of this general result, this paper designs a sliding controller for the
global chaos synchronization of hyperchaotic Yujun systems. Numerical results and simulations are shown to validate the proposed sliding controller design and demonstrate its effectiveness in achieving global chaos synchronization of hyperchaotic Yujun systems.
Dynamic stiffness and eigenvalues of nonlocal nano beams - new methods for dynamic analysis of nano-scale structures. This lecture gives a review and proposed new techniques.
Advanced Modeling & Simulation Techniques for Multibody Robotic SystemsDesign World
This webinar introduces new techniques and case studies for efficiently increasing the fidelity of system models for multibody robotic system design. Using symbolic computation techniques, multibody models can be effectively preprocessed to select optimal coordinate frames, eliminate redundant calculations, simplify algebraic constraints, and generate computationally minimal code for real-time deployment. Furthermore, novel mathematical techniques can be deployed for efficient parameter optimization and other advanced analysis.
Applications in robotics, including space and industrial robotics will be presented. The symbolic computation system Maple and the related modeling system MapleSim will be used to illustrate examples.
Attend this webinar to learn:
– How symbolic formulations can increase simulation speed without reducing model fidelity
– How high fidelity models can accelerate design time, reduce costly design errors, and ultimately improve the functional performance of robotics systems
This paper proposed a nonlinear robust control for spacecraft attitude based on passivity and
disturbance suppression vector. The spacecraft model was described using quaternion. The control law
introduced the suppression vector of external disturbances and had no information related to the system
parameters. The desired performance of spacecraft attitude control could be achieved using the designed
control law. And stability conditions of the nonlinear robust control for spacecraft attitude were given. The
stability could be proved by applying Lyapunov approach. The verification of the proposed attitude control
method was performed through a series of simulations. The numerical results showed the effectiveness of
the proposed control method in controlling the spacecraft attitude in the presence of external disturbances.
The main benefit of the proposed attitude control method does not need angular velocity measurement
and has its robustness against model uncertainties and external disturbances.
A Numerical Integration Scheme For The Dynamic Motion Of Rigid Bodies Using T...IJRES Journal
The dynamics of rigid bodies have been studied extensively. However, a certain class of time-integration schemes were not consistent since they added vectors not belonging to the same tangent space (so3), of the Lie group (SO3) of the Special Orthogonal transformations in E3. The work of Cardona[1,2], and later Makinen[3,4], highlighted this fact using the rotation vector as the main parameter in their derivations. Some other programs in multibody dynamics, such as the work of Haug[5], rely on the Euler parameters, instead of the rotation vector, as the main variable in their formulations. For this class of programs, different time-integration schemes could be used .This paper discusses one such a scheme. As an example of application, the spinning top was used in this paper. For such a problem, the approximate change of the potential energy was found to be an upper bound to the change in the actual total energy during a time step.
SLIDING MODE CONTROLLER DESIGN FOR GLOBAL CHAOS SYNCHRONIZATION OF COULLET SY...ijistjournal
This paper derives new results for the design of sliding mode controller for the global chaos synchronization of identical Coullet systems (1981). The synchronizer results derived in this paper for the complete chaos synchronization of identical hyperchaotic systems are established using sliding control theory and Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the sliding mode control method is very effective and convenient to achieve global chaos synchronization of the identical Coullet systems. Numerical simulations are shown to illustrate and validate the synchronization schemes derived in this paper for the identical Coullet systems.
Comparison of a triple inverted pendulum stabilization using optimal control ...Mustefa Jibril
In this paper, modelling design and analysis of a triple inverted pendulum have been done using
Matlab/Script toolbox. Since a triple inverted pendulum is highly nonlinear, strongly unstable
without using feedback control system. In this paper an optimal control method means a linear
quadratic regulator and pole placement controllers are used to stabilize the triple inverted
pendulum upside. The impulse response simulation of the open loop system shows us that the
pendulum is unstable. The comparison of the closed loop impulse response simulation of the
pendulum with LQR and pole placement controllers results that both controllers have stabilized
the system but the pendulum with LQR controllers have a high overshoot with long settling time
than the pendulum with pole placement controller. Finally the comparison results prove that the
pendulum with pole placement controller improve the stability of the system.
ANALYTICAL SOLUTIONS OF THE MODIFIED COULOMB POTENTIAL USING THE FACTORIZATIO...ijrap
We have solved exactly Schrödinger equation with modified Coulomb Potential under the framework of
factorization method. Energy levels and the corresponding wave functions in terms of associated Laquerre
function are also obtained. For further guide to interested readers we have computed the energy
eigenvalue for some selected elements for various values of n and l .
Asymptotic Stability of Quaternion-based Attitude Control System with Saturat...IJECEIAES
In the design of attitude control, rotational motion of the spacecraft is usually considered as a rotation of rigid body. Rotation matrix parameterization using quaternion can represent globally attitude of a rigid body rotational motions. However, the representation is not unique hence implies difficulties on the stability guarantee. This paper presents asymptotically stable analysis of a continuous scheme of quaternion-based control system that has saturation function. Simulations run show that the designed system applicable for a zero initial angular velocity case and a non-zero initial angular velocity case due to utilization of deadzone function as an element of the defined constraint in the stability analysis.
Vibration analysis and response characteristics of a half car model subjected...editorijrei
The displacement response of different masses of half car model. The analysis has been done for different car models also to see the dynamic response of the driver body coupled with the seat of a vehicle. It has been assumed the driver body is rigidly coupled with seat of the vehicle. The vehicle has been modeled for two D.O.F, in two D.O.F Half car model two motion (Pitch and Bounce) have been considered. The response of the vehicle has been obtained for different velocities and different amplitudes sinusoidal bump excitation.
Finite element modelling of nonlocal dynamic systems, Modal analysis of nonlocal dynamical systems, Dynamics of damped nonlocal systems, Numerical illustrations
SLIDING CONTROLLER DESIGN FOR THE GLOBAL CHAOS SYNCHRONIZATION OF IDENTICAL H...ijait
This paper establishes new results for the sliding controller design for the global chaos synchronization of identical hyperchaotic Yujun systems (2010). Hyperchaotic systems are chaotic nonlinear systems having more than one positive Lyapunov exponent. Because of the complex dynamics properties of hyperchaotic system such as high capacity, high security and high efficiency, they are very useful in secure
communication devices and data encryption. Using sliding mode control theory and Lyapunov stability theory, a general result has been obtained for the global chaos synchronization of identical chaotic nonlinear systems. As an application of this general result, this paper designs a sliding controller for the
global chaos synchronization of hyperchaotic Yujun systems. Numerical results and simulations are shown to validate the proposed sliding controller design and demonstrate its effectiveness in achieving global chaos synchronization of hyperchaotic Yujun systems.
Dynamic stiffness and eigenvalues of nonlocal nano beams - new methods for dynamic analysis of nano-scale structures. This lecture gives a review and proposed new techniques.
Advanced Modeling & Simulation Techniques for Multibody Robotic SystemsDesign World
This webinar introduces new techniques and case studies for efficiently increasing the fidelity of system models for multibody robotic system design. Using symbolic computation techniques, multibody models can be effectively preprocessed to select optimal coordinate frames, eliminate redundant calculations, simplify algebraic constraints, and generate computationally minimal code for real-time deployment. Furthermore, novel mathematical techniques can be deployed for efficient parameter optimization and other advanced analysis.
Applications in robotics, including space and industrial robotics will be presented. The symbolic computation system Maple and the related modeling system MapleSim will be used to illustrate examples.
Attend this webinar to learn:
– How symbolic formulations can increase simulation speed without reducing model fidelity
– How high fidelity models can accelerate design time, reduce costly design errors, and ultimately improve the functional performance of robotics systems
The Development of the Multi-body System Dynamics theory and the Absolute Nod...IJRES Journal
Elaborated the research background of multi-body system dynamics theory, points out the various systems of flexible system dynamics method. Systematically reviewed from four aspects of flexible multi body system dynamics is absolutely more than ten years since the birth of node coordinates method research progress, i.e., the system dynamics research progress of nonlinear multi-body system dynamics research progress, and the application of relevant research progress, finally put forward a series of research questions.
Comparison Of Multibody Dynamic Analysis Of Double Wishbone Suspension Using ...IJRES Journal
This paper presents the multibody dynamic analysis of wishbone suspension for automotive cars. Modeling and analysis of suspension is carried out using MATLAB SimMechanics toolbox. Rigid dynamic analysis of suspension is also carried out using ANSYS software. Results of both the analysis are compared and it is observed that results of both the analysis are similar.
An introduction to system dynamics & feedback loopbhupendra kumar
System dynamics focuses on the structure and behavior of systems composed of interacting feedback loops.
System Dynamics helps in designing the interconnections and structures to give more confidence and predictability in behavior of the systems.
This seminar slide will give you the ideas how much the ARTIFICIAL INTELLIGENCE is important gaming and what hard work should do for movements of other persons in a game.
This presentation is intended for giving an introduction to Genetic Algorithm. Using an example, it explains the different concepts used in Genetic Algorithm. If you are new to GA or want to refresh concepts , then it is a good resource for you.
Presentation is about genetic algorithms. Also it includes introduction to soft computing and hard computing. Hope it serves the purpose and be useful for reference.
Multibody dynamic analysis of mechanism for health excescise vibratoreSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Multibody dynamic analysis of mechanism for health excescise vibrator
Similar to Effects of clearance size on the dynamic response of planar multi body systems with differently located frictionless revolute clearance joints
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Modeling of the damped oscillations of the viscous beams structures with swiv...eSAT Journals
Abstract
Mechanic studies realized on the two dimensional beams structures with swivel joints show that in statics, the vertical displacement is
continuous, but the rotation is discontinuous at the node where there is a swivel joint. Moreover, in dynamics, many authors do not
usually take into account the friction effect, modeling of these structures. We propose in this paper, a modeling of the beams structures
with swivel joints which integrates viscosity effects in dynamics. Hence this work we will present the formulation of motion equations
of such structures and the modal analysis method which is used to solve these equations.
Keywords: Beams, Swivel joint, Viscosity, Vibration, Modal Method.
COMPARISON OF RESPONSE TO UNBALANCE OF OVERHUNG ROTOR SYSTEM FOR DIFFERENT SU...IAEME Publication
Rotor unbalance is most common fault found in the rotating machines. Methods
are adopted to analyze the position of unbalance and to bring its effect into acceptablelimit. Vibration analysis is the most common technique used to analyze the rotor
system. Research have been performed on rotor supported atboth ends, however lessstudy has been done for overhung rotor. In this paper the response of overhung rotoron isotropic support and anisotropic support subject tounbalance has been presented.and equations aresolved using MATLAB programming. The effect of unbalancehas been studied on thebode plot. Forward and Reverse whirl are observed through Campbell diagram andmode shapes are plotted.
Evaluation of Vibrational Behavior for A System With TwoDegree-of-Freedom Und...IJERA Editor
Analysis of the vibrational behavior of a system is extremely important, both for the evaluation of operating conditions, as performance and safety reason. The studies on vibration concentrate their efforts on understanding the natural phenomena and the development of mathematical theories to describe the vibration of physical systems. The purpose of this study is to evaluate an undamped system with two-degrees-of-freedom and demonstrate by comparing the results obtained in the experimental, numerical and analytical modeling the characteristics that describe a structure in terms of its natural characteristics. The experiment was conducted in PUC-MG where the data were acquired to determine the natural frequency of the system. We also developed an experimental test bed for vibrations studies for graduate and undergraduate students. In analytical modeling were represented all the important aspects of the system. In order, to obtain the mathematical equations is used MATLAB to solve the equations that describe the characteristics of system behavior. For the simulation and numerical solution of the system, we use a computational tool ABAQUS. The comparison between the results obtained in the experiment and the numerical was considered satisfactory using the exact solutions. This study demonstrates that calculation of the adopted conditions on a system with two-degrees-of-freedom can be applied to complex systems with many degrees of freedom and proved to be an excellent learning tool for determining the modal analysis of a system. One of the goals is to use the developed platform to be used as a didactical experiment system for vibration and modal analysis classes at PUC Minas. The idea is to give the students an opportunity to test, play, calculate and confirm the results in vibration and modal analysis in a low-cost platform
OPTIMAL TRAJECTORY OF ROBOT MANIPULATOR FOR ENERGY MINIMIZATION WITH QUARTIC ...cscpconf
In this paper, a different way to find the trajectory of the robot manipulators for energyoptimization is presented. In our method, the joint angles of the manipulator are set as quadratic polynomial functions. Then, with them taken into the variational function of energy consumption, Finite Element Modelling is employed to optimize the unknown parameters of the fourth order joint angles
Influence of joint clearance on kinematic and dynamic parameters of mechanismIOSR Journals
Kinematic joints for dynamic analysis of multi-body mechanical systems assumed ideal or perfect.
However, in a real mechanical kinematical joint clearance is always present. Such clearance is necessary for
the component assemblage and to allow the relative motion between the connected bodies. This clearance is
inevitable due to the manufacturing tolerances, material deformations, wear, and imperfections. The presence of
such joint clearance degrades the performance of mechanical systems in virtue of the contact and impact forces
that take place at the joint. Contact analysis is a computational bottleneck in mechanical design where the
contact changes. Manual analysis is time-consuming and prone to error. To address these problems, a
geometrical contact analysis method based on kinematic simulation, using CAD software is developed. An
equivalent kinematic linkage mechanism is constructed according to contact position of pin and hole assembly.
Results of kinematic and dynamic analysis of a four bar linkage with joint clearance shows that the contribution
of joint forces at slower input speed also degrades the performance of mechanism
The tensor language provides a unifying approach that simplifies notation, which leads to compact modeling of multi-way information objects in many knowledge fields, and a thought framework as well. By such a language, it is modeled a generic system that connects to environment through its boundaries.
SLIDING MODE CONTROLLER DESIGN FOR GLOBAL CHAOS SYNCHRONIZATION OF COULLET SY...ijistjournal
This paper derives new results for the design of sliding mode controller for the global chaos synchronization of identical Coullet systems (1981). The synchronizer results derived in this paper for the complete chaos synchronization of identical hyperchaotic systems are established using sliding control theory and Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the sliding mode control method is very effective and convenient to achieve global chaos synchronization of the identical Coullet systems. Numerical simulations are shown to illustrate and validate the synchronization schemes derived in this paper for the identical Coullet systems.
Simulink and Simelectronics based Position Control of a Coupled Mass-Spring D...IJECEIAES
This paper presents the use of Simelectronics Program for modeling and control of a two degrees-of freedom coupled mass-spring-damper mechanical system.The aims of this paper are to establish a mathematical model that represents the dynamic behaviour of a coupled mass-spring damper system and effectively control the mass position using both Simulink and Simelectronics.The mathematical model is derived based on the augmented Lagrange equation and to simulate the dynamic accurately a PD controller is implemented to compensate for the oscillation sustained by the system as a result of the complex conjugate pair poles near to the imaginary axis.The input force has been subjected to an obstacle to mimic actual challenges and to validate the mathematical model a Simulink and Simelectronics models were developed, consequently, the results of the models were compared. According to the result analysis, the controller tracked the position errors and stabilized the positions to zero within a settling time of 6.5sec and significantly reduced the overshoot by 99.5% and 99. 7% in Simulink and Simelectronics respectively. Furthermore, it is found that Simelectronics model proved to be capable having advantages of simplicity, less timeintense and requires no mathematical model over the Simulink approach.
Simulation, bifurcation, and stability analysis of a SEPIC converter control...IJECEIAES
This article presents some results of SEPIC converter dynamics when controlled by a center pulse width modulator controller (CPWM). The duty cycle is calculated using the ZAD (Zero Average Dynamics) technique. Results obtained using this technique show a great variety of non-linear phenomena such as bifurcations and chaos, as parameters associated with the switching surface. These phenomena have been studied in the present paper in numerical form. Simulations were done in MATLAB.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Similar to Effects of clearance size on the dynamic response of planar multi body systems with differently located frictionless revolute clearance joints (20)
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
To view the webinar recording, go to:
https://www.rttsweb.com/jmeter-integration-webinar
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
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Effects of clearance size on the dynamic response of planar multi body systems with differently located frictionless revolute clearance joints
1. Journal of Energy Technologies and Policy www.iiste.org
ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
Vol.2, No.3, 2012
Effects of Clearance Size on the Dynamic Response of Planar
Multi-body Systems with Differently Located Frictionless Revolute
Clearance Joints
Mutuku Muvengei1* John Kihiu1 Bernard Ikua2
1. Department of Mechanical Engineering, Jomo Kenyatta University of Agriculture and Technology PO Box
62000-00200, Nairobi, Kenya
2. Department of Mechatronic Engineering, Jomo Kenyatta University of Agriculture and Technology PO Box
62000-00200, Nairobi, Kenya.
*Corresponding Author: ommuvengei@gmail.com
Abstract
This paper numerically investigates the effects of clearance size of differently located revolute clearance joints
without friction on the overall dynamic characteristics of a multi-body system. A typical planar slider-crank
mechanism is used as a demonstration case in which the effects of clearance size of a revolute clearance joint
between the crank and connecting rod (c-cr), and between the connecting rod and slider (s-cr) are separately
investigated with comprehensive observations numerically presented. It is observed that, different joints in a
multi-body system have different sensitivities to the clearance size. Therefore the dynamic behavior of one clearance
revolute joint cannot be used as a general case for a mechanical system. Also the location of the clearance revolute
joint and the clearance size play a crucial role in predicting accurately the dynamic responses of the system.
Keywords: Chaotic behavior, Contact-impact force, Dynamic response, Multi-body mechanical system, Periodic
behavior, Poincare Map, Quasi-periodic behavior, revolute clearance joint.
1. Introduction
In traditional dynamic modeling of multi-body systems, the effect of clearance at the joints is routinely ignored in order
to simplify the dynamic model. The increasing requirement for high-speed and precise machines, mechanisms and
manipulators demands that the kinematic joints be treated in a realistic way. This is because in a real mechanical joint,
a clearance which permits the relative motion between the connected bodies as well as the components assemblage is
always present.
There is a significant amount of literature available which discuses theoretical and experimental analysis of imperfect
kinematic joints in a variety of planar and spatial mechanical systems with rigid or flexible links (Muvengei et al.
2011b). Many of these works focus on the planar systems in which only one kinematic joint is modeled as an imperfect
joint. Although, the results from such experimental and analytical models have been shown to provide important
insights on the behavior of mechanical systems with imperfect joints, the models do not allow for study of the
interactions of multiple kinematic imperfect joints. Furthermore a real mechanical system does not have only one real
joint, but practically all joints are real. This led several researchers such as Flores (2004) and Cheriyan (2006) to
strongly recommend for their work to be extended to include multi-body mechanical systems with multiple imperfect
joints, and with a variety of joints such as prismatic and universal joints. Few recent papers by Erkaya and Uzmay
(2009; 2010) and by Flores (2010a) have considered the nonlinear dynamic analysis of multi-body systems with two
imperfect joints. However in these research papers, only mechanisms with rigid links have been considered and the
interaction effects of the imperfect joints on the overall response of a multi-body system were not investigated. Also,
Erkaya and Uzmay (2009; 2010) modeled the clearance in the journal bearing as a massless imaginary link whose
length is equal to the clearance size. This assumption is not valid especially at large clearances because the journal and
bearing will not be in contact at all times.
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2. Journal of Energy Technologies and Policy www.iiste.org
ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
Vol.2, No.3, 2012
Majority of the research works on the study of clearance joints have assumed that differently located revolute joints
in a multi-body system when modeled as clearance joints affect the dynamic behavior of the system in a similar
manner. Hence the inherent observations derived from investigating the dynamic behavior of one clearance revolute
joint have been used as general cases for all the joints in the mechanical system. Therefore, the primary objective of
this research work is to investigate numerically if the clearance size of differently located revolute clearance joints in
a multi-body system affect the behavior of the system in a similar dynamic manner or not. This work will provide
inherent information which can be of great use in the analysis of multi-body systems with clearance joints especially
as it regards to the effective design and control tasks of these systems. This study will also form a base towards the
investigation of dynamic interaction of multiple revolute clearance joints in a multi-body mechanical system.
2. Equation of Motion of Multi-body Systems
The methodology adopted in this work to derive the dynamic equations of multi-body systems follows closely that of
Nikravesh (1988) in which the generalized Cartesian coordinates and the Newton-Euler's approach are utilized. The
methodology presented is implemented in a MATLAB code, which is capable of automatically generating and
solving the equations of motion for the multi-body systems.
Computationally, the dynamic analysis of a multi-body mechanical system with real or ideal joints involves solving
••
Equation (1) for the acceleration vector q and vector of Langrage multipliers λ (Shabana 1994). Then, in each
integration time step, the accelerations vector, together with velocities vector are integrated in order to obtain the
system velocities and positions for the next time step. This procedure is repeated until the final analysis time is
reached.
Qe
C q q
••
M T
= (1)
C 0 λ
q • • •
− (C q q) q q − 2C qt q − Ctt
M is the mass matrix, Cq is the Jacobi matrix and Qe is the vector containing the known external forces. The code
developed in this work was able to derive automatically the overall matrices in Equation (1) and subsequently solve
for the vectors of acceleration and Langrage multipliers, and finally integrate the vector for velocity and acceleration
to get the system positions and velocities for the next time step.
Since the system of the motion equations shown in Equation (1) does not use explicitly the position and velocity
equations associated with the kinematic constraints, chances are that the original constraint equations will be violated
during simulation. Due to simplicity and easiness of computational implementation, the Baumgarte Stabilization
Method (Baumgarte 1972) is employed in this work to control the position and velocity constraint violations brought
about by direct integration of Equation (1). By using the Baumgarte's approach, the equations of motion for a
dynamic system subjected to holonomic constraints are represented as,
••
M C q q
T
Qe
= • (2)
C 0 λ Qd − 2α C − β 2C
q
Where C is the vector of constraint equations and α and β are termed as feedback parameters which should be
arbitrary chosen.
2.1. Kinematic Model of a Revolute Joint with Clearance
Figure 1 shows two bodies i and j connected with a revolute joint with clearance. Part of body i is the bearing while
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3. Journal of Energy Technologies and Policy www.iiste.org
ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
Vol.2, No.3, 2012
part of body j is the journal.
The eccentricity vector which connects the centers of the bearing and the journal is given as,
→
e = rPj − rpi = (R j + Aj uPj ) − ( Ri + Ai uPi ) (3)
The magnitude of the eccentricity vector is
→T →
e= e e (4)
The penetration depth due to the impact between the journal and the bearing can be shown to be,
δ = e−c (5)
Where c is the radial clearance at the joint which is the difference between the radius of the bearing and the radius of
the journal of the clearance joint. The contact points on bodies i and j during indentation are Ci and Cj respectively as
shown in Figure 1.
→
→ e
n= (6)
e
The velocity of the contact points in the global coordinate system is,
→
• • • •
r Ci = R i + Ai u Pi + RB n (7)
→
• • • •
r Cj = R j + A j u Pj + RJ n (8)
→
Where n is the unit vector in the direction of indentation due to impact between the journal and the bearing, and
RB and RJ are the bearing and journal radii respectively.
The components of the relative velocity of the contact points in the normal and tangential plane of collision are given
as,
→ • • →
v N = (r Cj − r Ci ) n (9)
→ • • →
v T = (r Cj − r Ci ) t (10)
→ →
Where t is a unit vector obtained by rotating n anticlockwise by 900.
2.2. Dynamic Model of a Revolute Joint with Clearance
When the journal makes contact with the bearing, then impacts occur and contact-impact forces are created at the
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4. Journal of Energy Technologies and Policy www.iiste.org
ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
Vol.2, No.3, 2012
joint. Closer inspection of Equation (5) shows that:
• When the journal is not in contact with the bearing, e<c and the indentation has a negative value. In this
case, the journal is in free-flight motion inside the bearing, and no impact-contact forces are created.
• When contact between the journal and the bearing is established, the indentation has a value equal or greater
than zero. In this case, impact-contact forces at the joint are established.
Therefore the computational algorithm developed for dynamic analysis of a system with revolute clearance joint
should ensure that impact-contact forces are applied when the depth of penetration is greater or equal to zero.
Since there are velocity components in the normal and tangential directions of the collision between the journal and
the bearings as given in Equation (9) and (10) then forces are generated in these two directions. The force normal to
the direction of collision FN can be evaluated using the contact force laws, such as Hertz, Lankarani-Nikravesh,
Dubowsky-Freudenstein or ESDU-78035 contact models, while the force tangential to the direction of collision FT
which is the frictional force is evaluated using the appropriate frictional laws.
In this paper, it is assumed that no frictional forces are generated during the collision of the bearing and the journal;
however friction will be included in further work. Since the direction of the normal unit vector is used as the working
direction for the contact forces, then the contact forces at body i is;
→
FNi = FN n (11)
From the Newton's third law of motion, the contact reaction force at body j will be;
FNj = − FNi (12)
These forces which act at the contact points are transferred to the center of masses of bodies i and j as shown in
Figure 2. This transfer of forces from contact forces to the center of masses contributes to the moments given as,
M i = ( xCi − xi ) FNiY − ( yCi − yi ) FNiX (13)
M j = ( xCi − xi ) FNjY − ( yCi − yi ) FNjX (14)
Once these forces and moments are known and added to the generalized vector of external forces Qe in Equation (2),
then the description of the revolute joint with clearance is complete. No kinematic constraint was used when
modeling the real joint; instead force constraints have been used.
2.3. Contact Force Models
Once the journal makes contact with the bearing, forces normal to the direction of contact are created. In this work
the nonlinear continuous contact force models between two colliding bodies will be used since they represent the
physical nature of the contacting surfaces. These contact force modes include; Hertz, Lankarani-Nikravesh,
Dubowsky-Freudenstein and ESDU-78035 contact force models. A detailed description of these contact-force
models is available in (Muvengei et al. 2011b).
It has been shown by several researchers such as (Flores et al. 2006;Muvengei et al. 2011a) that the two cylindrical
contact models (that is, Dubowsky-Freudenstein and ESDU-78035 contact models) do not present any added
advantage compared to the elastic spherical contact model (that is, the Hertz contact model). However, the
cylindrical models are nonlinear and implicit functions, and therefore they require an iterative procedure such as
Newton-Raphson algorithm to solve them which is computationally time consuming. In this work therefore,
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5. Journal of Energy Technologies and Policy www.iiste.org
ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
Vol.2, No.3, 2012
Lankarani-Nikravesh contact force model represented in Equation (15) is used to evaluate the force normal to the
direction of collision since it accounts for energy dissipation during the impact process.
•
3(1 − ce2 ) δ
FN = Kδ 1 +n
•
(15)
4δ (−)
Exponent n=1.5 for metallic surfaces and the generalized stiffness K which depends on the material properties and
the shape of the contacting surfaces is given as;
1
4 R1 R2 2
K= (16)
3(σ 1 + σ 2 ) R1 + R2
Where R1 and R2 are the radii of the contacting spheres (the radius is negative for concave surfaces and positive for
convex surfaces), and σi‘s are material parameters given by,
1 − υ i2
σi = for i=1, 2
Ei
With Ei and υi being the Young’s modulus and the Poisson’s ratio of each contacting sphere.
3. Results and Discussion
This section contains extensive results obtained from computational simulations of a slider-crank mechanism with a
revolute clearance joint. This study takes into account two main functional parameters of the slider-crank mechanism,
that is, the location of the considered clearance joint and the clearance size.
3.1 Description of the Slider-Crank Mechanism
A typical slider-crank mechanism as shown in Figure 3 is used as a demonstrative example to study the parametric
effect of revolute joint clearance on the dynamic response of a multi-body mechanical system.
The slider-crank mechanism considered has the following parameters: Length of crank LOA=0.05m, length of the
coupler link LAB=0.12m, mass of the crank m2=0.3kg, mass of the coupler m3=0.21kg, mass of the slider m4=0.14kg,
moment of inertia of crank I2=0.00001kg.m2 and moment of inertia of coupler I3=0.00025kg.m2. In addition all the
links are assumed to be uniform such that their centers of gravity are at their geometric centers. The following are
other parameters used for the different contact models: Nominal bearing diameter d=10mm, Length of the cylindrical
contact between the journal and the bearing L=20mm, Coefficient of restitution ce=0.9, Young's modulus E=207MPa,
Poisson's ratio υ=0.3 and reporting time step is 0.000001s.
The dynamic response of the slider-crank mechanism is presented by plotting the variations with time of the slider
velocity, slider acceleration and torque required to maintain constant speed of the crank. The behavior of the revolute
clearance joints is also illustrated by using the slider velocity and the slider acceleration to plot the phase portraits at
different test scenarios.
3.2 Influence of the Clearance Size
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6. Journal of Energy Technologies and Policy www.iiste.org
ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
Vol.2, No.3, 2012
In this subsection, the influence of the clearance size at c-cr joint and also at s-cr joint on the dynamic behavior of the
slider-crank mechanism is investigated and comparisons presented. The range of the clearances used at each joint is
0.01mm, 0.1mm, 0.3mm and 0.5mm, and the crank rotates uniformly at 5000rev/min.
Figures 4 and 6 show that increasing the clearance size of a revolute joint, the mechanism experiences increased
peaks of the slider acceleration. This implies that at higher joint clearances, higher impacts followed by rebounds
take place, instead of continuous or permanent contact between the journal and the bearing walls. When the
clearance is small, the system response tends to be closer to the ideal response as evident in Figures 4(a) and 6(a).
This implies that at smaller clearance, the journal and the bearing of the joint experience a smaller number of impacts
and the journal follows the bearing wall. This is also evident in the phase portraits presented in Figures 5 for c-cr
from which it is clearly observed that increasing the radial clearance of this joint from 0.01mm to 0.5mm, the
behavior of the system changes from periodic to quasi-periodic. This quasi-periodic behavior is evident in the phase
portrait diagram because at large clearance sizes (0.3mm and 0.5mm), cycles of the mechanism fill up the diagram in
a fully predictable manner. When the clearance is small (0.01mm and 0.1mm), the behavior of the system tends to be
periodic since the cycles of the mechanism follow the same path in the phase portrait diagram. However, increasing
the clearance size beyond 0.5mm the behavior of the system changed from quasi-periodic to chaotic. At large
clearance sizes such as 0.3mm and 0.5mm, the three types of journal motion inside the bearing are clearly observed,
namely, the free-flight motion, the impact mode and the permanent or continuous contact mode.
However, as seen in Figure 7 increasing the radial clearance of the s-cr joint from 0.01mm to 0.5mm, the behavior of
the system changes from periodic to quasi-periodic, and then to chaotic. The chaotic behavior is evident in Figure 7(d)
since at a joint clearance of 0.5mm, different cycles of the mechanism lead to different curves in the phase portrait
diagram in an unpredictable manner. These observations are consistent with those made by (Flores et al. 2010b,
Flores et al. 2007) who investigated the effect of clearance size of a gudgeon joint (s-cr joint) on the behavior of a
slider-crank mechanism. This behavior is different from the one witnessed when only c-cr joint was modeled as a
revolute clearance joint, in which at a clearance of 0.5mm the behavior of the system was still quasi-periodic. This
shows that the dynamics of the revolute clearance s-cr joint in the slider-crank mechanism is more sensitive to the
clearance size as compared to that of revolute clearance c-cr joint. This confirms the already made observation that,
dynamic response peaks of the mechanism when s-cr joint is modeled as a real joint are higher than the peaks
produced when c-cr joint is modeled as a real joint with the same radial clearances. Although, the clearances of
different joints in a system show almost the same effects on the dynamic response of the system, it has been shown
that the joints will have different sensitivities to the clearance size. Therefore in order to design effective controllers
for eliminating fully the chaotic behaviors brought about by the non-linearities of joints with clearances, the dynamic
effect of each joint on the system should be understood, that is, the effects of clearance sizes in one joint cannot be
used as a general case in a mechanical system.
4. Conclusions
From the numerical simulations presented in this work, it can be concluded that the dynamic response of a
multi-body mechanical system with revolute clearance joint depends on the location of the joint and the clearance
size of the joint. It is clear that the dynamics of the revolute clearance joint in a mechanical system is quite sensitive
to the clearance size such that by slightly changing the value of the clearance size, the response of the system can
shift from chaotic to periodic behavior. However, the degree of sensitivity to the clearance size varies from one joint
to another. For instance in a slider-crank mechanism, the joint between the slider and connecting rod is more
sensitive to the clearance size than the joint between the crank and the connecting rod. This explains why many
researchers have emphasized on modeling the joint between the slider and connecting rod as a clearance joint.
Therefore in order to design effective controllers for eliminating fully the chaotic behaviors brought about by the
non-linearities of joints with clearances, the dynamic effect of each joint on the system should be understood. This is
because the effects of the clearance sizes in one clearance joint cannot be used as a general case in a mechanical
system.
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Vol.2, No.3, 2012
References
Baumgarte, J. (1972), “Stabilization of constraints and integrals of motion in dynamical systems,” Journal of
Computer Methods in Applied Mechanics and Engineering, vol. 1, pp. 1–16.
Cheriyan, S. K. (2006), “Characterization of Mechanical Systems with Real Joints and Flexible Links”, PhD. Thesis,
Wichita State University.
Erkaya, S., & Uzmay, I. (2009), “Investigation on effect of joint clearance on dynamics of four-bar mechanism”
Journal of Nonlinear Dynamics, vol. 58, pp. 179–198.
Erkaya, S., & Uzmay, I. (2010) “Experimental investigation of joint clearance effects on the dynamics of a slider-crank
mechanism” Journal of Multibody System Dynamics, vol. 24, pp. 81–102.
Flores, P. (2004a), “Dynamic Analysis of Mechanical Systems with Imperfect Kinematic Joints”, PhD. Thesis,
UNIVERSIDADE DO MINHO PARA.
Flores, P., & Ambrosio, J. (2004b), “Revolute joints with clearance in multibody systems,” Journal of Computers and
Structures, vol. 82, pp. 1359–1369.
Flores, P., Ambrosio, J., Claro, J. C. P., Lankarani, H. M. & Koshy, C. S. (2006a), “A study on dynamics of mechanical
systems including joints with clearance and lubrication”, Journal of Mechanism and Machine Theory, vol. 41, pp.
247-261.
Flores, P., Ambrosio, J., Claro, J. C. P., & Lankarani, H. M. (2006b), “Influence of the contact-impact force model on
the dynamic response of multi-body systems”, Journal of Multibody Dynamics, vol. 220, pp. 21-34.
Flores, P., Ambrosio, J., Claro, J. C. P., & Lankarani, H. M. (2007), “Dynamic behavior of planar rigid multibody
systems including revolute joints with clearance, Journal of Multibody Dynamics 161-174.
Flores, P., (2010a), “A parametric study on the dynamic response of planar multibody systems with multiple clearance
joints” Journal of Nonlinear Dynamics, vol. 4, pp. 633–653.
Flores, P., Koshy, C., Lankarani, H., Ambrosio, J., & Claro, J. (2010b), “Numerical and experimental investigation on
multibody systems with revolute clearance joints”, Journal of Nonlinear Dynamics.
Lankarani, H. M., & Nikravesh, P. E. (1990), “A contact force model with hysteresis damping for impact analysis of
multibody systems” Journal of Mechanical Design, vol. 112, pp. 369–376.
Muvengei, O., Kihiu, J. and Ikua, B. (2011a) “Effects of input speed on the dynamic response of planar multi-body
systems with differently located frictionless revolute clearance joints”. International Journal Mechanical and Materials
Engineering, vol. 4, pp. 234-243.
Muvengei, O. M. Kihiu, J. & Ikua, B. (2011b), “Dynamic Analysis of Multi-Body Mechanical Systems with
Imperfect Kinematic Joints: A Literature Survey and Review”, Sustainable Research and Innovation Conference,
JKUAT.
Nikravesh, P.E. (1988), Computer-Aided Analysis of Mechanical Systems, Prentice Hall, Englewood Cliffs, New
Jersey.
Shabana, A. A. (1994), Computational Dynamics, John Wiley & Sons, New York.
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ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online)
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Figure 1: Penetration depth due to impact between the bearing and the journal
Figure 2: Transfer of impact forces to the center of masses of the bodies
Figure 3: Slider-crank mechanism
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Figure 4. Slider acceleration responses for different clearance sizes at c-cr joint (a) 0.01mm (b) 0.1mm (c) 0.3mm (d)
0.5mm
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Figure 5. Phase portraits for different clearance sizes at c-cr joint (a) 0.01mm (b) 0.1mm (c) 0.3mm (d)0.5mm
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Figure 6. Slider acceleration responses for different clearance sizes at s-cr joint (a) 0.01mm (b) 0.1mm (c) 0.3mm (d)
0.5mm
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Figure 7. Phase portraits for different clearance sizes at s-cr joint (a) 0.01mm (b) 0.1mm (c) 0.3mm (d)0.5mm
18
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