Uniform Global Asymptotic Stability of an Adaptive Output Feedback Tracking Controller for Robot Manipulators (original) (raw)

Global adaptive output feedback tracking control of robot manipulators

2000

Abstract This paper presents a solution to the problem of global, output feedback, tracking control of uncertain robot manipulators, specifically, a desired compensation adaptation law plus a nonlinear feedback term coupled to a dynamic nonlinear filter is designed to produce global asymptotic link position tracking while compensating for parametric uncertainty and requiring only link position measurements

Scrutiny of Nonlinear Adaptive Output Feedback Control for Robotic Manipulators

Springer International Publishing, 2014

In this paper we present a nonlinear adaptive output feedback control algorithm. The algorithm is for model reference adaptive control of robotic manipulators. This algorithm uses model signals in the regressor and the linearization law and hence, does not require an observer. We show via various simulations that this algorithm has a region of convergence. We also show that the region of convergence can be increased if a normalizing factor is used in the adaptation law.

On global output feedback tracking control of robot manipulators

2000

We revisit the global output feedback (OFB) tracking control problem for rigid-link robot manipulators subject to parametric uncertainty. Motivated by misunderstandings in the literature concerning our previous result, we propose a new global OFB adaptive controller which, in contrast to our previous work, eliminates the need for a post-stability analysis transformation to derive a velocity-independent control strategy. The structure of the new controller along with a new Lyapunov function are used to illustrate global asymptotic link position tracking. Experimental results are included to demonstrate the controller performance

A composite adaptive output feedback tracking controller for robotic manipulators

1999

Abstract This paper provides a solution to the composite adaptive output feedback tracking control problem for robotic manipulators. The proposed controller utilizes an update law that is a composite of a gradient update law driven by the link position tracking error and a least squares update law driven by the prediction error. In order to remove the controller's dependence on link velocity measurements, a linear filter and a new prediction error formulation are designed.

Output-feedback adaptive control for the global regulation of robot manipulators with bounded inputs

International Journal of Control, Automation and Systems, 2013

In this paper, an output-feedback adaptive scheme for the global position stabilization of robot manipulators with bounded inputs is proposed. Compared to the previous output-feedback adaptive approaches developed in a bounded-input context, the proposed free-ofvelocity feedback controller guarantees the adaptive regulation objective: globally, avoiding discontinuities throughout the scheme, preventing the inputs to reach their natural saturation bounds, and imposing no saturation-avoidance restriction on the control gains. Moreover, the developed scheme is not restricted to the use of a specific saturation function to achieve the required boundedness, but may involve any one within a set of smooth and non-smooth (Lipschitz-continuous) bounded passive functions that include the hyperbolic tangent and the conventional saturation as particular cases. Experimental results corroborate the efficiency of the proposed scheme.

An adaptive output feedback controller for robot arms: stability and experiments

Automatica, 2001

An adaptive output feedback controller for robot arms is developed in this paper. A nonlinear observer based on desired joint velocities and bounded joint position error is used to estimate joint velocities. Experimental results validate the ewectiveness of the proposed adaptive output feedback controller.

Global robust output feedback tracking control of robot manipulators

Robotica, 2004

This paper addresses the problem of global output feedback, link position tracking control of robot manipulators. Specifically, a robust, Lyapunov-based controller is designed to ensure that the link position tracking error is globally uniformly ultimately bounded despite the fact that only link position measurements are available in the presence of incomplete model information (i.e., parametric uncertainty and additive bounded disturbances).

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 generalized global adaptive tracking control scheme for robot manipulators with bounded inputs

International Journal of Adaptive Control and Signal Processing, 2014

In this work, a generalized adaptive scheme for the global motion control of robot manipulators with constrained inputs is proposed. It gives rise to various families of bounded adaptive controllers defined through a general class of saturation functions. Compared with adaptive tracking control algorithms previously developed in a bounded-input context, the proposed adaptive approach guarantees the motion control objective for any initial condition, avoiding discontinuities throughout the scheme, preventing the inputs to reach their natural saturation bounds, and permitting innovation on the saturating structure through its generalized form, giving a wide range of possibilities for performance improvement. Experimental results corroborate the efficiency of the proposed scheme.

On robust adaptive control of robot manipulators

Automatica, 1992

In this paper we present a robust adaptive control scheme for robot manipulators with time-varying parameters and unmodeled dynamics. Our scheme ensures that all signals in the closed-loop robot system are bounded and the tracking error is of the order of the parameter variations and unmodeled dynamics in the mean.