On Robust Adaptive PD Control of Robot Manipulators (original) (raw)
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Adaptive PD-SMC for Nonlinear Robotic Manipulator Tracking Control
Studies in Informatics and Control, 2017
This paper presents an adaptive and robust control scheme, which is based on Sliding Mode Control (SMC) accompanied by Proportional Derivative (PD) control terms for trajectory tracking of nonlinear robotic manipulators in the presence of system uncertainties and external disturbances. Two important features make the proposed control method more suitable for tracking control of robotic manipulators in comparison with SMC. One of these features is the model free nature of proposed control, which implies avoiding the need to determine dynamic model of the controlled system. As a second feature, control and adaption technique used in the proposed method cancels the need for determining the upper bounds of uncertainties. It should be emphasized that SMC requires the dynamic model of the system and prior knowledge of upper bound of uncertainties. Lyapunov theory is used to prove stability of proposed method and a four link SCARA robot is selected for demonstrating efficacy of the proposed method via simulation tests. Simulation tests are utilized to compare the proposed method with conventional SMC in terms of tracking control performance and cumulative error. Results have revealed significant improvement in both aspects.
Adaptive control of robot manipulator motion
IEEE Transactions on Robotics and Automation, 1990
This paper presents algorithms for continuous-time direct adaptive control of robot manipulatord. Lyapunov theory ig used for controller design and stability investigaüion. Algorithms for rapid continuous-time adaptive control are presented. Key wotdls Adaptive control, Lyapunov stabilit¡ Zz-stabilit¡ Robot control, Rapid parameter estimation. Classifrcatíon systcrn and/or índcx t*ms (if urry) Supplcmentary b íblío gaphícal ínforznat íon ISSN and kcy titlc ISBN Languagc English Numbc¡ of pageø 19 Rccipient'c noúcs Sccurity c lassifrcat io n The rcpofi mzy bc o¡dcrcd frorlrt thc Department of Automatìc Cont¡ol ot bo¡towed through the tJnivcrsity Líbrary 2, Box 107A, 5-227 Og Lund, Swedcn, Telex: 33248 lubbìs lund.
Design of a robust adaptive control law for robotic manipulators
Journal of Robotic Systems, 1994
In this article, a robust adaptive control scheme for robotic manipulators is designed based on the concept of performance index and Lyapunov's second method. Compensators are selected for a given feedback system by using a quadratic performance index. Then the stability of the system is proven based on Lyapunov's method, where a Lyapunov function and its time-derivative are derived from the selected compensators. In the process of stabilization, stability bounds are obtained for disturbances, control gains, adaptation gains, and desired trajectories, in the presence of feedback delay due to digital computation and first-order hold in the control loop. 0 2994 john Wiley 6 Sons, Znc.
An adaptive control law for robotic manipulator without velocity feedback
Control Engineering Practice, 2003
In this paper a new adaptive control law is designed for robotic manipulators, based on the use of reference velocities instead of the actual ones and feedback signals generated from position errors. The law in question is suitable for trajectory tracking and positioning tasks. Its peculiarities are: a) high signal to noise ratio in the control torques; b) absence of parameter drift in positioning tasks. Simulation and experimental tests are shown with the aim to both confirm the validity and illustrate the actual characteristics of the proposed control law.
Adaptive Control of Robot Manipulator
—Robot manipulators have become major component of manufacturing industries due to he advantages associated with them like high speed, accuracy and repeata-bility.Two link robot manipulator is a very basic classical and simple example of robot followed in understanding of basic fundamentals of robotic manipulator. Due to uncertainties and non-linearities involved in its behavior, it is a challenging task to control their motion. This paper focuses mainly on the control of robot manipulator by employing design of various controllers like the PD controller, computed torque controller, adaptive controller and a robust adaptive controller. Their design and their performances are compared in extensive simulations carried out in MATLAB/Simulink.
Adaptive control of robot manipulator having friction and uncertainties
Journal of Advanced Research in Dynamical and Control Systems
A novel approach for adaptive control of robot manipulators having friction and other uncertainties using exponential estimation laws has been proposed. Proposed estimation law is based on time varying parameters and depends upon the system dynamics and tracking error. Friction is an important aspect for control design of mechanical systems, including robotics, because it can lead to tracking errors, limit cycles, and undesired stick-slip motion. The developed error derived adaptive compensator ensures global position tracking when applied to an n degree of freedom manipulator perturbed by friction forces, random external disturbances, measurement noise, and all the system parameters (robot and friction model) unknown. Simulation results show an acceptable performance of our compensator compared with another adaptive friction compensator previously reported.
Adaptive Nonlinear Control Algorithms for Robotic Manipulators
In this paper some adaptive nonlinear multivariable techniques used in the control of robotic manipulators are presented. The nonlinear control law and state feedback are used in achieving a linear inputoutput behavior for the controlled system. For the design of the adaptive nonlinear control, the exact feedback input-output linearization and the method of gradient are used. The nonlinear control law achieves also decoupling. Computer simulations are included to demonstrate some theoretical aspects and the performances of these controllers for a typical structure of robotic manipulator.
2014
This paper proposes an adaptive trajectory control method for a 2DOF planar rigid link robot arm with arbitrary link length. The transient response can be improved by a dynamic certainty equivalent controller with nonlinear friction compensator and a dead zone adaptation law to be robust to bounded friction compensation error. Also, the adaptation law accompanies with a smooth projection algorithm which not only confines adjustable parameters of adaptive controller into a certain convex set to guarantee a positive definiteness of estimated inertia matrix but also ensures the differentiability of those. The convex set is designed by taking into account the existence region of the parameters of the robot arm with expected loads.