Multi-mode switching between controllers corresponding to different modes of operation is needed in those cases when the transition from one mode to another results in substantial flight-critical variations in the aircraft dynamics. To address this problem, a general framework for multi-modal flight control is proposed. The framework is based on the Multiple Models, Switching and Tuning (MMST) methodology, combined with Model-Predictive Control (MPC), and the use of different robust mechanisms for switching between the multi-modal controllers. It was shown that many different switching control strategies can be naturally derived from the basic framework, which demonstrates the generality of the proposed approach.
Worker Scheduling for Maintenance Modeling SoftwareIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Methods for Risk Management of Mining Excavator through FMEA and FMECAtheijes
Management of maintenance systems in the mining industry is an important condition for their operation. If we recognize the need for risk analysis and management of individual maintenance system, it can generate potential overall efficiency and effectiveness. Special importance for the realization of the objectives of the mining industry belongs to redesign, system harmonization between the various technical structure, standardization, technical diagnostics, analysis of different levels of criticality with variant selection and application of optimal solutions. The potential for the destruction of the complex maintenance systems are a reality in the mining industry and their expression in various applications is a realistic one. For different aspects of the analysis it is possible to decrease risk index range from the threshold to the range of high and low threshold of moderate and acceptable risk. Application of FMEA (Failure Mode and Effect Analysis) and FMECA (Failure Modes, Effects and Criticality Analysis) methods are used to manage risk related to the initial phase of defining the prediction of all possible risks, risk factors and RPN budget priorities. Some risks can be grouped according to the type of errors that occur due to their realization. For effective risk analysis and implement measures to reduce their need is and competent team. No matter what the risks involved, FMECA method can reliably estimate the possibility of their implementation with a satisfactory degree of flexibility and compatibility. In this paper an attempt has been made to develop an effective maintenance methodology of excavator such that the maintenance cost is minimized and technical constraints (such as engine, hydraulic and transmission system, break system, electrical and safety system, suspension and track) are efficiently monitored and maintained. These technical constraints depends upon many factors such as a) Geotechnical parameters, b) Geological parameters, c) Mine parameters, d) Production rate, e) Equipment specification and f) Dig ability assessment etc. Based on the above factors maintenance plans are prepared. This paper discusses a risk management strategy system for Optimal Maintenance Program (OMP) of excavators. The OMP includes functional analysis method of FMEA and FMECA. To develop a successful operation system, it is first necessary to create a risk management program. A prudent management program is one that ensures safety and is environmentally and economically responsible.
Guidelines to Understanding to estimate MTBFijsrd.com
To quantifying a reparable system or reliability we can use MTBF. It has been used for various decisions. MTBF is determining the reliability. For developing the MTBF model we can use Poisson distribution, Weibull model and Bayesian are the most popular approach. In this paper we are talking about complexities and misconceptions of MTBF and clarify in sequence what are the items and concerns that need to be consider in estimating MTBF.
A developer needs to evaluate software performance metrics such as power consumption at an early stage of design phase to make a device or a software efficient especially in real-time embedded systems. Constructing performance models and evaluation techniques of a given system requires a significant effort. This paper presents a framework to bridge between a Functional Modeling Approach such as FSM, UML etc. and an Analytical (Mathematical) Modeling Approach such as Hierarchical Performance Modeling (HPM) as a technique to find the expected average power consumption for different layers of abstractions. A Hierarchical Generic FSM “HGFSM” is developed to be used in order to estimate the expected average power. A case study is presented to illustrate the concepts of how the framework is used to estimate the average power and energy produced.
Worker Scheduling for Maintenance Modeling SoftwareIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Methods for Risk Management of Mining Excavator through FMEA and FMECAtheijes
Management of maintenance systems in the mining industry is an important condition for their operation. If we recognize the need for risk analysis and management of individual maintenance system, it can generate potential overall efficiency and effectiveness. Special importance for the realization of the objectives of the mining industry belongs to redesign, system harmonization between the various technical structure, standardization, technical diagnostics, analysis of different levels of criticality with variant selection and application of optimal solutions. The potential for the destruction of the complex maintenance systems are a reality in the mining industry and their expression in various applications is a realistic one. For different aspects of the analysis it is possible to decrease risk index range from the threshold to the range of high and low threshold of moderate and acceptable risk. Application of FMEA (Failure Mode and Effect Analysis) and FMECA (Failure Modes, Effects and Criticality Analysis) methods are used to manage risk related to the initial phase of defining the prediction of all possible risks, risk factors and RPN budget priorities. Some risks can be grouped according to the type of errors that occur due to their realization. For effective risk analysis and implement measures to reduce their need is and competent team. No matter what the risks involved, FMECA method can reliably estimate the possibility of their implementation with a satisfactory degree of flexibility and compatibility. In this paper an attempt has been made to develop an effective maintenance methodology of excavator such that the maintenance cost is minimized and technical constraints (such as engine, hydraulic and transmission system, break system, electrical and safety system, suspension and track) are efficiently monitored and maintained. These technical constraints depends upon many factors such as a) Geotechnical parameters, b) Geological parameters, c) Mine parameters, d) Production rate, e) Equipment specification and f) Dig ability assessment etc. Based on the above factors maintenance plans are prepared. This paper discusses a risk management strategy system for Optimal Maintenance Program (OMP) of excavators. The OMP includes functional analysis method of FMEA and FMECA. To develop a successful operation system, it is first necessary to create a risk management program. A prudent management program is one that ensures safety and is environmentally and economically responsible.
Guidelines to Understanding to estimate MTBFijsrd.com
To quantifying a reparable system or reliability we can use MTBF. It has been used for various decisions. MTBF is determining the reliability. For developing the MTBF model we can use Poisson distribution, Weibull model and Bayesian are the most popular approach. In this paper we are talking about complexities and misconceptions of MTBF and clarify in sequence what are the items and concerns that need to be consider in estimating MTBF.
A developer needs to evaluate software performance metrics such as power consumption at an early stage of design phase to make a device or a software efficient especially in real-time embedded systems. Constructing performance models and evaluation techniques of a given system requires a significant effort. This paper presents a framework to bridge between a Functional Modeling Approach such as FSM, UML etc. and an Analytical (Mathematical) Modeling Approach such as Hierarchical Performance Modeling (HPM) as a technique to find the expected average power consumption for different layers of abstractions. A Hierarchical Generic FSM “HGFSM” is developed to be used in order to estimate the expected average power. A case study is presented to illustrate the concepts of how the framework is used to estimate the average power and energy produced.
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.
Effect of stability indices on robustness and system response in coefficient ...eSAT Journals
Abstract
In Control systems, designing a robust controller such that a desired system response is obtained despite plant parameter
variations is ubiquitous problem. In this context, Coefficient diagram method is an effective method and one of the recent design
methods based on the polynomial approach introduced by Shunji Manabe. In CDM, stability indices, stability limits and time
constant are the main design parameters. The stability indices and stability limits are indicative of stability and equivalent time
constant is indicative of speed of system response. A semi-log diagram known as coefficient diagram is the design tool using
which one can analyse the important features of a design such as stability, speed of response and robustness, all in one diagram.
The right choice of the stability indices is of paramount importance in the controller design. This paper deals with the effect of
variation in the stability indices upon the system response and robustness. A type 2 fourth order plant has been considered as an
example to analyse the effects of stability indices. The stability indices are varied one by one relative to the standard Manabe form
and in each case response is observed. The transient response of the system is sensitive to lower order indices. Also, robustness in
the design is analysed by coefficient diagrams of the perturbed plant.
Keywords: Coefficient Diagram Method (CDM), robustness; Stability Indices, Coefficient Diagram
Validation of Maintenance Policy of Steel Plant Machine Shop By Analytic Hier...IJMERJOURNAL
ABSTRACT: In this paper the maintenance activities of the Machine shop of Steel plant have been considered. As maintenance is a routine activity to keep a machine at its normal operating condition so that it can deliver its expected performance without causing any loose of time on account of accidental damage or breakdown and maintenance is a recurring activity. So for reduction of maintenance cost and safety of the operator as well as the residents of nearby area it is better to decide which machines should go for which type of maintenance. For this decision AHP is used and the Expert choice software is used for that calculations and this paper is for the validation of results.
Adaptive PI Controller for Voltage Regulation in Power SystemsISA Interchange
Static synchronous compensator (STATCOM) provides the means to improve quality and reliability of a power system as it has the functional capability to handle dynamic disturbances, such as transient stability and power oscillation damping as well as to providing voltage regulation. In this paper, a robust adaptive PI-based optimal fuzzy control strategy is proposed to control a STATCOM used in distribution systems. The proposed intelligent strategy is based on a combination of a new General Type-II Fuzzy Logic (GT2FL) with a simple heuristic algorithm named Teaching Learning Based Optimization (TLBO) Algorithm. The proposed framework optimally tunes parameters of a Proportional-Integral (PI) controller which, similar to most of other researchers regarding control of STATCOM, are in charge of controlling the device. The proposed controller guaranties robustness and stability against uncertainties caused by external disturbances or ever-changing nature of the power systems. The TLBO optimizes the parameters of the controller as well as the input and output membership functions. To validate the efficiency of the proposed controller, the obtained simulation results are compared with those of the two most recent researches applied in this field, namely, conventional Proportional Integral (PI) controller and Optimal Fuzzy PI (OFPI) controller. Results demonstrate the successfulness and effectiveness of the proposed online-TLBO General Type-2 Fuzzy PI (OGT2FPI) controller and its superiority over conventional approaches.
Trajectory Control With MPC For A Robot Manipülatör Using ANN ModelIJMER
In this study, in a computer the dynamic motion modelling of manipulator and control of
trajectory with an algorithm this has been tested. First after dynamic motion simulation of manipulator
has been made MPC Control. The result in this study we can observe that computed torque method gives
better results than MPC methods. So in trajectory control it is approved of using computed torque
method. In last part of this study the results are estimated forward development are exemined and
suggested. The model predictive control (MPC) technique for an articulated robot with n joints is
introduced in this paper. The proposed MPC control action is conceptually different with the trajectory
robot control methods in that the control action is determined by optimising a performance index over
the time horizon. A neural network (NN) is used in this paper as the predictive model.
www.ijera.com 68 | P a g e Leaf Disease Detection Using Arm7 and Image Proces...IJERA Editor
In an agricultural field plant diseases are very important aspect as it directly affect on the production of plant and economical value of market. In this research generally we uses image processing technique that is automatically detect symptoms of the disease as early as possible. This is the first and important phase for automatic detection and classification of plant diseases. There are some stages to find the disease like image acquisition, preprocessing on image, color transform usingYCbCr, segmentation using Otsu method, feature extraction using Gabor filter method and classification using SVM, using those steps we can surely detect the disease and classified it and also can take preventive measures.
Torsional-Distortional Performance of Multi-Cell Trapezoidal Box Girder with ...IJERA Editor
In this study, the torsional and distortional performance of a three triangular cell trapezoidal box girder section was studied using Vlasov’s theory of thin walled structures. The potential energy of a system under equilibrium was used to obtain the governing differential equations of equilibrium for torsionl-distortional analysis of the box structure. The strain modes diagrams representing torsional and distortional interactions of the box girder structure were obtained as well as the distortional bending moment diagram for the box girder structure. These were used to compute Vlasov’s coefficients contained in the differential equations of equilibrium. The fourth order differential equations obtained were solved using method of trigonometric series with accelerated convergence to obtain the distortional and torsional deformations which were compared with torsional and distortional deformations of a single cell mono symmetric box girder section of similar overall dimensions and plates thicknesses. The maximum distortional deformation was found to be 168% lower than that of a single cell mono-symmetric box girder section of the same size and dimensions. The inclined internal web members, which also act as diaphragms, brought about increase in the pure torsional and distortional components of the applied torsional load, resulting to marginal increase in the torsional deformation but major decrease in the distortional deformation.
The Use of Reclaimed Asphalt Pavement as a Foundation for Pavements Based On ...IJERA Editor
This research aims to determine the use of materials from reclaimed asphalt pavement layers directly with the addition of virgin aggregates without the addition of other additives (filler) intended for quality improvement based on the 2010 general specifications of the Indonesian National Standard. Utilization of these materials was used for base courses (class A), sub-base courses (class B), and courses without asphalt coverings (class S). The method used was the laboratory-experiment method and the analysis of the relationship was made using the regression equation. Based on the analysis, by combining the mixture with the virgin aggregates, it was revealed that the materials from reclaimed asphalt pavement layers can be used for the base courses by no more than 3 percent, for the sub-base courses by no more than 9 percent, and for the courses without asphalt coverings or shoulders by no more than 10 percent.
Implementation Of Syntax Parser For English Language Using Grammar RulesIJERA Editor
From many years we have been using Chomsky‟s generative system of grammars, particularly context-free grammars (CFGs) and regular expressions (REs), to express the syntax of programming languages and protocols. Syntactic parsing mainly works with syntactic structure of a sentence. The 'syntax' refers to the grammatical and syntactical arrangement of words in a sentence and their relationship with other words. The main focus of syntactic analysis is important to find syntactic structure of a sentence which usually is represented as a tree structure. To identify the syntactic structure is useful in determining the meaning of a sentence Natural language processing processes the data through lexical analysis, Syntax analysis, Semantic analysis, and Discourse processing, Pragmatic analysis. This paper gives various parsing methods. The algorithm in this paper splits the English sentences into parts using POS (Parts Of Speech) tagger, It identifies the type of sentence (Simple, Complex, Interrogate, Facts, active, passive etc.) and then parses these sentences using grammar rules of Natural language. As natural language processing becomes an increasingly relevant, there is a need for tree banks catered to the specific needs of more individualized systems. Here, we present the open source technique to check and correct the grammar. The methodology will give appropriate grammatical suggestions.
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.
Effect of stability indices on robustness and system response in coefficient ...eSAT Journals
Abstract
In Control systems, designing a robust controller such that a desired system response is obtained despite plant parameter
variations is ubiquitous problem. In this context, Coefficient diagram method is an effective method and one of the recent design
methods based on the polynomial approach introduced by Shunji Manabe. In CDM, stability indices, stability limits and time
constant are the main design parameters. The stability indices and stability limits are indicative of stability and equivalent time
constant is indicative of speed of system response. A semi-log diagram known as coefficient diagram is the design tool using
which one can analyse the important features of a design such as stability, speed of response and robustness, all in one diagram.
The right choice of the stability indices is of paramount importance in the controller design. This paper deals with the effect of
variation in the stability indices upon the system response and robustness. A type 2 fourth order plant has been considered as an
example to analyse the effects of stability indices. The stability indices are varied one by one relative to the standard Manabe form
and in each case response is observed. The transient response of the system is sensitive to lower order indices. Also, robustness in
the design is analysed by coefficient diagrams of the perturbed plant.
Keywords: Coefficient Diagram Method (CDM), robustness; Stability Indices, Coefficient Diagram
Validation of Maintenance Policy of Steel Plant Machine Shop By Analytic Hier...IJMERJOURNAL
ABSTRACT: In this paper the maintenance activities of the Machine shop of Steel plant have been considered. As maintenance is a routine activity to keep a machine at its normal operating condition so that it can deliver its expected performance without causing any loose of time on account of accidental damage or breakdown and maintenance is a recurring activity. So for reduction of maintenance cost and safety of the operator as well as the residents of nearby area it is better to decide which machines should go for which type of maintenance. For this decision AHP is used and the Expert choice software is used for that calculations and this paper is for the validation of results.
Adaptive PI Controller for Voltage Regulation in Power SystemsISA Interchange
Static synchronous compensator (STATCOM) provides the means to improve quality and reliability of a power system as it has the functional capability to handle dynamic disturbances, such as transient stability and power oscillation damping as well as to providing voltage regulation. In this paper, a robust adaptive PI-based optimal fuzzy control strategy is proposed to control a STATCOM used in distribution systems. The proposed intelligent strategy is based on a combination of a new General Type-II Fuzzy Logic (GT2FL) with a simple heuristic algorithm named Teaching Learning Based Optimization (TLBO) Algorithm. The proposed framework optimally tunes parameters of a Proportional-Integral (PI) controller which, similar to most of other researchers regarding control of STATCOM, are in charge of controlling the device. The proposed controller guaranties robustness and stability against uncertainties caused by external disturbances or ever-changing nature of the power systems. The TLBO optimizes the parameters of the controller as well as the input and output membership functions. To validate the efficiency of the proposed controller, the obtained simulation results are compared with those of the two most recent researches applied in this field, namely, conventional Proportional Integral (PI) controller and Optimal Fuzzy PI (OFPI) controller. Results demonstrate the successfulness and effectiveness of the proposed online-TLBO General Type-2 Fuzzy PI (OGT2FPI) controller and its superiority over conventional approaches.
Trajectory Control With MPC For A Robot Manipülatör Using ANN ModelIJMER
In this study, in a computer the dynamic motion modelling of manipulator and control of
trajectory with an algorithm this has been tested. First after dynamic motion simulation of manipulator
has been made MPC Control. The result in this study we can observe that computed torque method gives
better results than MPC methods. So in trajectory control it is approved of using computed torque
method. In last part of this study the results are estimated forward development are exemined and
suggested. The model predictive control (MPC) technique for an articulated robot with n joints is
introduced in this paper. The proposed MPC control action is conceptually different with the trajectory
robot control methods in that the control action is determined by optimising a performance index over
the time horizon. A neural network (NN) is used in this paper as the predictive model.
www.ijera.com 68 | P a g e Leaf Disease Detection Using Arm7 and Image Proces...IJERA Editor
In an agricultural field plant diseases are very important aspect as it directly affect on the production of plant and economical value of market. In this research generally we uses image processing technique that is automatically detect symptoms of the disease as early as possible. This is the first and important phase for automatic detection and classification of plant diseases. There are some stages to find the disease like image acquisition, preprocessing on image, color transform usingYCbCr, segmentation using Otsu method, feature extraction using Gabor filter method and classification using SVM, using those steps we can surely detect the disease and classified it and also can take preventive measures.
Torsional-Distortional Performance of Multi-Cell Trapezoidal Box Girder with ...IJERA Editor
In this study, the torsional and distortional performance of a three triangular cell trapezoidal box girder section was studied using Vlasov’s theory of thin walled structures. The potential energy of a system under equilibrium was used to obtain the governing differential equations of equilibrium for torsionl-distortional analysis of the box structure. The strain modes diagrams representing torsional and distortional interactions of the box girder structure were obtained as well as the distortional bending moment diagram for the box girder structure. These were used to compute Vlasov’s coefficients contained in the differential equations of equilibrium. The fourth order differential equations obtained were solved using method of trigonometric series with accelerated convergence to obtain the distortional and torsional deformations which were compared with torsional and distortional deformations of a single cell mono symmetric box girder section of similar overall dimensions and plates thicknesses. The maximum distortional deformation was found to be 168% lower than that of a single cell mono-symmetric box girder section of the same size and dimensions. The inclined internal web members, which also act as diaphragms, brought about increase in the pure torsional and distortional components of the applied torsional load, resulting to marginal increase in the torsional deformation but major decrease in the distortional deformation.
The Use of Reclaimed Asphalt Pavement as a Foundation for Pavements Based On ...IJERA Editor
This research aims to determine the use of materials from reclaimed asphalt pavement layers directly with the addition of virgin aggregates without the addition of other additives (filler) intended for quality improvement based on the 2010 general specifications of the Indonesian National Standard. Utilization of these materials was used for base courses (class A), sub-base courses (class B), and courses without asphalt coverings (class S). The method used was the laboratory-experiment method and the analysis of the relationship was made using the regression equation. Based on the analysis, by combining the mixture with the virgin aggregates, it was revealed that the materials from reclaimed asphalt pavement layers can be used for the base courses by no more than 3 percent, for the sub-base courses by no more than 9 percent, and for the courses without asphalt coverings or shoulders by no more than 10 percent.
Implementation Of Syntax Parser For English Language Using Grammar RulesIJERA Editor
From many years we have been using Chomsky‟s generative system of grammars, particularly context-free grammars (CFGs) and regular expressions (REs), to express the syntax of programming languages and protocols. Syntactic parsing mainly works with syntactic structure of a sentence. The 'syntax' refers to the grammatical and syntactical arrangement of words in a sentence and their relationship with other words. The main focus of syntactic analysis is important to find syntactic structure of a sentence which usually is represented as a tree structure. To identify the syntactic structure is useful in determining the meaning of a sentence Natural language processing processes the data through lexical analysis, Syntax analysis, Semantic analysis, and Discourse processing, Pragmatic analysis. This paper gives various parsing methods. The algorithm in this paper splits the English sentences into parts using POS (Parts Of Speech) tagger, It identifies the type of sentence (Simple, Complex, Interrogate, Facts, active, passive etc.) and then parses these sentences using grammar rules of Natural language. As natural language processing becomes an increasingly relevant, there is a need for tree banks catered to the specific needs of more individualized systems. Here, we present the open source technique to check and correct the grammar. The methodology will give appropriate grammatical suggestions.
Revista Conmemorativa a los 24 Años de fundacion de Grupo Diarqco y su amplia gama de servicios de ingenieria, arquitectura, tecnologias y servicios en el ramo petrolero; siendo esta última como la primera empresa petrolera privadas 100% tabasqueña. Grupo Diarqco comenzó a operar en 1993 en la Ciudad de Villahermosa, Tabasco, México como un pequeño despacho de Diseño, asistido por Computadora (CAD, por sus siglas en Inglés), ofreciendo, inicialmente, servicios de maquila a despachos de arquitectos y constructoras del Estado de Tabasco.
Komunikácia na sociálnej sieti Facebook predstavuje základný pilier online marketingu. Pripravili sme pre vás prezentáciu, v ktorej sa dozviete, ako správne komunikovať s cieľovou skupinou a ako využívať reklamný priestor, ktorý ponúka.
Viac zaujímavých rád a aktuálnych informácií zo sveta Facebooku nájdete na našom blogu Grappastudio.
https://www.grappa.sk/blog/facebook/
Buzzing Stocks in D-Street before European OpeningShailesh Saraf
It has been observed that the stocks which show buying, have either good volume or some news. They stay buzzing stocks for that day and big movement is expected in these stock throughout day. SRF Ltd rose 8.10% in intraday trading at Rs. 1756; recently the company announced that there is room for expansion in nonwovens in India.
A Brief Research On Turbojet Engine By Using MPM 20IJERA Editor
Small turbojet engines represent a special class of turbine driven engines. They are suitable for scientific
purposes and research of certain thermodynamic processes ongoing in turbojet engines. Moreover such engines
can be used for research in the area of alternative fuels and new methods of digital control and measurement.
Our research, which is also presented in this article, is headed toward these aims. We evaluate and propose a
system of digital measurement of a particular small turbojet engine – MPM 20. Such engine can be considered
as highly non-linear large scale system. According to obtained data and experiments we propose different model
models of the engine and design of situational control algorithms for the engine with use of certain methods of
artificial intelligence as new methods of control and modeling of large scale systems.
Automatic Landing of a UAV Using Model Predictive Control for the Surveillanc...AM Publications
The objective of this paper is to provide safe landing of an UAV on any demanding conditions and can be very useful during the period of floods, rescuing the affected people. It can be also be useful in military operations. This system provides stable method for landing of an aircraft. Image processing technique is used to capture the image and find the angle of inclinations. MATLAB produces four types of image through Image processing technique. They are Gray image, Edge Detection image, Histogram image, object detection image. MATLAB sends the histogram signal to microcontroller using UART. It is used to convert the received parallel data into serial data for transmitting the data to longer distance. Relay drives the DC motor. Angle of inclinations is measured according to the detected image of the surface. MATLAB produces the total inclination value of the surface. DC motor automatically adjusts the landing gear according to the obtained input inclination value of the surface. An UAV is programmed to adjust the landing gear according to angle of inclination. When the landing surface is detected for landing the aircraft, it automatically adjusts the landing gear and lands the aircraft according to the inclined surface of the landing area.
A predictive sliding mode control for quadrotor’s tracking trajectory subject...IJECEIAES
In this paper, a predictive sliding mode control (PSMC) strategy for the quadrotors tracking trajectory problem is proposed. This strategy aims to combine the advantages of sliding mode control (SMC) and non-linear model predictive control (NMPC) to improve the tracking control performance for quadrotors in terms of optimality, inputs/states constraints satisfaction, and strong robustness against disturbances. A comparative study of three popular controllers: the SMC, NMPC, and the integral backstepping control (IBC) is performed with different criteria. Accordingly, IBC and SMC show less computational time and strong robustness, while NMPC has minimum control effort. The discrete Dryden turbulence model is used as a benchmark model to represent the wind effect on the trajectory tracking accuracy. The effectiveness of the proposed method PSMC has been proven and compared with discrete-time sliding mode control (DSMC) and NMPC in several scenarios. Simulation results show that under both wind turbulence and time-variant uncertainties, the PSMC outperforms the other controllers by providing simultaneously disturbance rejection and guarantee that the control inputs are within bounded constraints.
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 .
Mixed H2/H∞ robust controllers in aircraft control problemIJECEIAES
A leading cause of accidents during the landing phase of a flight lies in a considerable altitude loss by an aircraft as a result of the impact of a microburst of wind. One of the significant factors focuses primarily on the need to simultaneously satisfy various requirements regarding conditions of environmental disturbances and a wide range of systemic changes. The paper presents an algorithm for synthesizing an optimal controller that solves the mixed H2/H∞ control problem for the stabilization of aircraft in glide-path landing mode in the presence of uncertainty. Firstly, the principles of multi-criteria optimization are presented, and the mixed H2/H∞ problem is interpreted as the synthesis of a system with optimal quadratic performance, subject to its readiness to operate with the worst disturbance. Then, the ensuing section expounds upon the mathematical depiction of the vertical trajectory of aircraft, duly considering the perturbations imposed by wind phenomena. Subsequently, the effectiveness of mixed H2/H∞ control is confirmed compared to autonomous H2 or H∞ regulators through simulation outcomes acquired from the created system. Optimization based on a hybrid (mixed) criterion allowed combining the strengths of locally optimal systems based only on H2 or H∞ theory.
Adaptive Control strategies helps to get desirable output for system with partial unknown dynamics or systems having unknown and unmodeled load variation. DC servo motors are useful to track rapid speed trajectory for various applications, particularly with need of high starting torque and low inertia. Model Reference Adaptive Control (MRAC) parameter data of results with Lyapunov stability MRAC has been used to generate adaptation parameter for DC motor speed controller.
Efficiency of bond graph and external model integration for alarm processing ...IJAAS Team
The design of a supervision system based on the external model by structuring the industrial process according to several modes of operation (degraded and normal). The disadvantage of this model is that it describes the industrial process components as functions regardless of their dynamics without going into detail. Hence the interest of the bond graph model to fill the external model limits. The performance of the proposed supervisory system using both models lies in the detection and location of faults for each mode of operation. The bond graph model enriched by the concept of causality and thanks to these structural properties can clearly display the elements of the physical system taking into account their dynamics in normal and abnormal operation. The results of our research have been applied to central air conditioning system; the development of the proposed project has proceeded from the modeling stage to the reconfiguration stage of the system.
Induction motors are work-horse of the industry and major element in energy conversion. The replacement of the existing non-adjustable speed drives with the modern variable frequency drives would save considerable amount of electricity. A proper control scheme for variable frequency drives can enhance the efficiency and performance of the drive. This paper attempt to provide a rigorous review of various control schemes for the induction motor control and provides critical analysis and guidelines for the future research work. A detailed study of sensor based control schemes and sensor-less control schemes has been investigated. The operation, advantages, and limitations of the various control schemes are highlighted and different types of optimization techniques have been suggested to overcome the limitations of control techniques.
Optimal Maintainability of Hydraulic Excavator Through Fmea/FmecaIJRESJOURNAL
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An Overview of Adaptive Approaches in Flight Control
1. Y. Rajeshwari Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 5, Issue 1( Part 5), January 2015, pp.45-50
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An Overview of Adaptive Approaches in Flight Control
Y. Rajeshwari, V. Rajeswari
Prof. & Head, ICE Dept. GNITS Engg.,College
Assistant Professor,ICE Dept. GNITS.Engg., College
Abstract
Multi-mode switching between controllers corresponding to different modes of operation is needed in
those cases when the transition from one mode to another results in substantial flight-critical variations in the
aircraft dynamics. To address this problem, a general framework for multi-modal flight control is
proposed. The framework is based on the Multiple Models, Switching and Tuning (MMST)
methodology, combined with Model-Predictive Control (MPC), and the use of different robust mechanisms
for switching between the multi-modal controllers. It was shown that many different switching control
strategies can be naturally derived from the basic framework, which demonstrates the generality of the
proposed approach.
Key words: MMST, MPC, Mode prediction, Flight control, Switching, Optimization
I. Introduction
Multi-modal control can be broadly defined as a
set of control strategies used to achieve the pre-
specified objectives for a controlled vehicle in
different modes of operation. Modes of operation
are related to the vehicle dynamics and its
environment. For instance, in the case of air
vehicles, possible modes of operation include
mission modes and internal and external modes.
Those are described below.
Mission Modes: During a mission, the vehicle
goes through different modes of operation. For
instance, during a strike mission an advanced combat
aircraft goes through take-off, super-cruise, low-
altitude ingress, target strike, air combat
maneuvering, low altitude egress, powered
approach, and landing.In general, in those modes,
different control strategies are used to achieve the
desired performance. In this context, the desired
performance includes not only the requirement
for accurate tracking of commanded signals,
but also that of optimal guidance to assure low
signature, optimum fuel consumption etc.
One widely used strategy for air vehicles
operating in different flight regimes is Gain
Scheduling shown in Figure 1
closed-loop system.
While this strategy has been widely used in
practice, its main disadvantage is that the stability
and robustness of the overall system is difficult to
predict, particularly in the presence of unanticipated
events such as disturbances, failures, battle damage, et
cetera.
Internal Modes: Common variations of the air
vehicle dynamics during different segments of a
mission are due to fuel consumption, store release,
weight changes (in the case of air drops), usage of
different engines (as in hypersonic vehicles), et
cetera. During transitions between these modes
either a sufficiently robust baseline control strategy
or a gain-scheduled controller can be used.
However, of particular importance in this
context are failure modes since unexpected failures
of flight-critical subsystems or components can lead
to substantial performance degradation and even to
the loss of the vehicle. Such failures include sensor,
control effector, actuator and engine failures, and
failures of avionics subsystems and the flight
computer. While there are methods available for on-
line Failure Detection and Identification (FDI) and
Adaptive Reconfigurable Control (ARC) of
advanced fighter aircraft [1,2,3], a
comprehensive approach that can handle multiple
simultaneous failures of flight-critical subsystems
and components has not been developed yet.
External Modes: can be described as those
arising from unexpected variations in the
environments encountered by the vehicle. These
include: (i) Loss of communication with the
command center or other team members; (ii) Very
large external disturbances; (iii) Battle damage; and
(iv) Sudden pop-up threats. In such cases,
advanced identification, FDI-ARC, and estimation
RESEARCH ARTICLE OPEN ACCESS
2. Y. Rajeshwari Int. Journal of Engineering Research and Applications www.ijera.com
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algorithms are needed to stabilize the vehicle and
achieve at least some minimum tolerable
performance. While some of the partial solutions to
this problem are available [4,6,8], there is a need to
develop a comprehensive Autonomous Intelligent
Flight Control Systems (AI-FCS) that can achieve
the desired objectives despite encountering
unanticipated modes of operation. The design of
such AI-FCSs is one of the key research areas in
SSCI.
Multi Modal Control Systems (MMCS) and AI-
FCS should have a capability to handle efficiently
mission modes under unexpected internal and
external variations. This objective should be
achievable with the available control authority,
which emphasizes the importance of real-time
Control Input Redundancy Management for on-line
MMCS and AI-FCS.
Basic elements of MMCS and AI-FCS include:
• Redundancy management
• Mode prediction
• Disturbance estimation and rejection
• Failure Detection and Identification (FDI) and
Damage Detection and Identification (DDI) as a
part of the Health Management System (HMS),
• State estimation and filtering, and
• Decision making subsystem(s).
An AI-FCS under development by SSCI, is shown
in Figure 2.
Figure 2: Structure of the AI-FCS
In this context, of particular importance is mode
prediction, since, based on the models of the
vehicle and its environment, the transitions between
different modes can be predicted, and this
information can be used to choose the best control
strategy. Such a MMCS is shown in Figure 3.
The overall AI-FCS should, hence, combine the
following strategies:
• MMST, where multiple observers can be used
for specifying a number of different modes of
operation related to failures, battle damage and the
presence of large disturbances;
• MPC that can be used for prediction of the
modes of operation and for ARC in the
presence of failures and uncertainties under
different constraints; and
• Multi-layer hierarchical control structure for
specifying the links between the executable
levels and decision-making subsystems.
Model-Predictive Control (MPC)
MPC is an optimal control approach
involving direct use of both linear and nonlinear
internal models of a plant and on-line
optimization techniques to assure that the objective
of tracking a desired trajectory is achieved under
constraints on the control inputs, states and outputs.
One of the most important aspects of the MPC
is that it can explicitly account for both position and
rate limits on the control effectors, which is a
unique capability in comparison with other
available control strategies.
Other important aspects include the fact that the
internal model of the MPC can be either linear or
nonlinear, and that it can be identified and changed
on-line for a fully adaptive MPC design. In
addition, the MPC-based multiple model FDI-ARC
schemes have been demonstrated as highly effective
for achieving the control objectives in the presence
of severe subsystem or component failures.
Structure of an MPC scheme is shown in Figure
4.
The internal model of the plant has the same
input as the actual plant, and its output approximates
the true output.
The observer (predictor) predicts the future
output of the plant T steps ahead based on the
internal model, while, over the same prediction
horizon 7, the reference model generates a trajectory
that the future outputs should follow.
The optimization technique commonly used in
the context of MPC is a constrained Sequential
Quadratic Programming (SQP) algorithm. It is
3. Y. Rajeshwari Int. Journal of Engineering Research and Applications www.ijera.com
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based on a quadratic cost functional J that depends
on the values of the tracking error over the
prediction horizon T, and on the control input
values over the control horizon M. This cost
functional is subject to the constraints on states,
output and inputs. The MPC algorithm calculates an
optimal sequence of control inputs by minimizing J
over T, applies the first element of the input
sequence to the plant, and repeats the procedure. The
concept of MPC is shown in figure 5.
Figure 5: Model Predictive Control Philosophy
We will next discuss the applications of the
MMST concept in the design of MMCS and AI-
FCSs.
Multiple Models, Switching, and Tuning
(MMST)
The concept of MMST has been extensively
used by SSCI in the context of both aircraft
and spacecraft control [5]—[10]. Its main
advantages over single model-based adaptive
controllers are summarized below:
1. The MMST-based schemes can achieve effective
control reconfiguration and excellent overall
performance even in the case of severe failures
when single model adaptive controllers fail to
achieve the objective.
2. MMST appears to be the only available approach
that can be used to solve the problem of efficient
adaptive control reconfiguration for TAFA in the
presence of severe wing damage.
3. A particularly attractive feature of the
MMST controllers is that they result in a stable
overall system despite the presence of severe
failures and wing damage.
The basic comparison of the MMST controller with
a single model adaptive controller is described in
Figure 6.
As shown in the figure, failure may cause the
plant dynamics to switch abruptly from some
nominal point Po in the parametric space, to the point
P corresponding to the failed plant.
The top figure illustrates the case when
adaptation using a single model may be too slow to
identify the new operating regime and
reconfigure the controller. In such a case placing
several models in the parametric set, switching to
the model close to the dynamics of the failed plant,
and adapting from there can result in fast and
accurate control reconfiguration.
The concept of MMST is based on the idea of
describing the dynamics of the system using
different models for different operating regimes;
such models identify in some sense the current
dynamics of the system and are consequently
referred to as the identification models or observers.
The basic idea is to set up such
identification models (observers) and corresponding
controllers in parallel, Figure 7, and to devise a
suitable strategy for switching among the controllers
to achieve the desired control objective. While the
plant is being controlled using one of these
controllers, the identification models are run in
parallel to generate some measure of the
corresponding identification errors and find a model
which is, in some sense, closest to the current
4. Y. Rajeshwari Int. Journal of Engineering Research and Applications www.ijera.com
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operating regime of the plant.
Once such a model is found, the switching
mechanism switches to (or stays at) the
corresponding controller assuring overall stability.
In the context of reconfigurable control design
in the presence of parametric uncertainties and/or
sensor, actuator and structural failures, the
identification models (observers) MIf...,MN from
Figure 7 correspond to different regions in the
parameter space characterizing different types of
failures, while C/,...,C/v denote the corresponding
controllers. Such an approach was used in [5,7,9,10]
for adaptive reconfigurable control design, yielding
excellent performance of the overall system in the
presence of severe failures and battle damage.
II. Design of Multi-Modal Algorithms
using Combined Switching
Controllers
In general, the aircraft dynamics is characterized
by transitions between different modes of operation.
Such variation in the dynamics may be due to
transitions between different flight regimes, or the
effect of large external disturbances, or to
subsystem and/or component failures. In such cases,
different strategies for FDI-ARC and AI-FCS
design are needed for different modes of operation.
In this context, one viable approach is that based
on MMST. To take into account different
constraints, an adaptive MPC needs to be used
within the multiple model framework.
The emphasis of the overall design then needs to
be on different performance specifications and
different control strategies in different modes of
operation, and a multi-modal approach to on-line
control redesign for transition between different
modes and control reconfiguration in the presence
of failures.
One of the related problems is the choice of
the most suitable control strategies in different
modes of operation. As it is well known, the
Inverse Dynamics Control Law (IDCL) algorithm
[23] is computationally simple and easy to
implement. However, it does not take into account
explicitly position and rate limits on the control
effectors, which may cause unacceptable transients
and even instability of the overall system. On the
other hand, the MPC strategy takes these
constraints into account but is computationally
intensive. Hence a viable compromise is a control
strategy that uses the IDCL as long as there is no rate
or position limiting, and switches to the MPC when
one or more inputs are about to saturate. The
proposed scheme is shown in Fgure R.
Such a scheme needs to be developed in the
context of MMST to assure overall stability and
robustness to uncertainties.
An important aspect of such an approach is
that even in the cases when the IDCL is used to
control the aircraft, the MPC estimator is running
an providing predicted values of the state of the
system, which is an important information for
higher decision-making levels.
III. Parameter Estimation-Based
Switching Control
Another approach that appears well suited for the
problem under consideration is that based on
estimation-based switching among the controllers.
This approach is motivated by our results obtain in
[9], and is illustrated in Figure 9.
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The basic idea is to use the on-line estimates of
the aircraft parameters to decide which controller to
choose in a particular flight regime or mode of
operation. As seen in the Figure, if the plant
dynamics abruptly switches from the point Po to
point P in the parametric set, the estimate will
moves through the parametric set trying to identify
the model corresponding to the point P. The
parametric set is divided into subsets so that each
subset there is a corresponding controller Cj,...,C4
that achieves the objective for all values of
parameters from the subset. As the estimate moves
into a particular subset, the scheme switches to the
corresponding controller. To prevent chattering, a
hysteresis switching rule can be used.
A particularly attractive feature of this approach
is that it appears that the stability of the overall system
can be explicitly proved, which is not the case with
standard gain-scheduled controllers.
Prediction-Based Switching Control
An interesting observation in this context is that,
conceptually, there is no difference between
parameter estimation-based switching control and
prediction-based switching control. In particular, let
the plant go through transitions among different sets
in the state space, where, for each set we have the
corresponding controller Cj,...yCN. If the controller
gains are changed based on the variation of some of
the state variables, we have gain scheduling. If the
gains are changed based on on-line parameter
estimates, we have indirect adaptive control
In the previous sections we discussed switching
between different controllers based either on the
control input or parameter estimates. Another
promising strategy is that based on the predicted
state of the system. In particular, we can run the
MPC to arrive at the values of the state T steps
ahead. If the predicted state moves to a different set
in the state space, we can switch to the
corresponding controller based on this prediction.
IV. Conclusions
In this paper we propose a general framework for
multi-mode switching in flight control. From the
flight control design point of view, multi-mode
switching between controllers corresponding to
different modes of operation is needed in those cases
when the transition from one mode to another results
in substantial flight-critical variations in the aircraft
dynamics.
To address this problem, a general framework
for multi-modal flight control is proposed. The frame
work is based on the Multiple Models Switching and
Tuning (MMST) methodology, combined with
Model-Predictive Control (MPC), and using
different robust mechanisms for switching between
the multi-modal controllers. It is shown that many
different switching control strategies can be
naturally derived from the basic framework, which
demonstrates the generality of proposed approach.
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