On robust adaptive control of robot manipulators (original) (raw)

A robust adaptive controller for robot manipulators

Proceedings 1992 IEEE International Conference on Robotics and Automation

In the present paper we propose a globally convergent adaptive control scheme for robot motion control with the following features: First, the adaptation law possesses enhanced robustness with respect to noisy velocity measurements. Secondly, the controllex does not require the inclusion of high gain loops that may excite the unmodeled dynamics and amplify the noise level. Thirdly, we derive for the known parameter design a relationship between compensator gains and closed-loop convergence rates which is independent of the robot task. This helps the designer to carry out the gain tuning with an eye on the robustnessperformance tradeoff.

A Robust Adaptive Robot Controller

A globally convergent adaptive control scheme for robot motion control with the following features is proposed. First, the adaptation law possesses enhanced robustness with respect to noisy velocity measurements. Second, the controller does not require the inclusion of high gain loops that may excite the unmodeled dynamics and amplify the noise level. Third, we derive for the unknown parameter design a relationship between compensator gains and closed-loop convergence rates that is independent of the robot task. A simulation example of a two-DOF manipulator features some aspects of the control scheme.

Robust Adaptive Control and its Application to a Mechanical Manipulator

Proceedings. The First IEEE Regional Conference on Aerospace Control Systems,, 1993

This paper presents a practical robust adaptive control scheme to deal with real systems in the presence of structured and unstructured uncertainties. An application of the proposed robust adaptive control scheme for a mechanical manipulator has been developed and numerically demonstrated.

Design parameters and uncertainty bound estimation functions for adaptive-robust control of robot manipulators

2012

In this paper, a parameter and uncertainty bound estimation functions for adaptive-robust control of robot manipulators are developed. A Lyapunov function is defined and parameters and uncertainty bound estimation functions are developed based on the Lyapunov function. Thus, stability of an uncertain system is guaranteed and uniform boundedness of the tracking error is achieved. As distinct from previous parameter and bound estimation laws, the parameters and uncertainty bounds are updated as a function of a combination of trigonometric function depending on robot parameters and tracking error. Based on the same Lyapunov function, a robust control law is also defined and the stability of the uncertain system is proved under the same set of conditions. Simulation results are given to illustrate the tracking performance of the proposed adaptive-robust controller.

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.

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.

Variable Upper Bounding Approach for Adaptive-Robust Control in Robot Control

2003

This paper presents a new adaptive-robust control law for robot manipulators with parametric uncertainty. Stability of the uncertain system has been guaranteed using the Lyapunov theory and the control law is derived by means of analytical approach. In this scheme, the manipulator parameters are determined with an estimation law, and both adaptive gain and additional control input are also updated as a function of the estimated value. The proposed adaptive control input includes a parameter estimation law as an adaptive controller and an additional control input vector as a robust controller. The developed approach has the advantages of both adaptive and robust control laws, and besides it eliminates the disadvantages of them.