New results on adaptive compliance control for dexterous manipulators

Abstract

This paper presents two adaptive schemes for controlling dexterous manipulators to enable reliable execution of tasks that require contact with an unknown environment. The first scheme is developed using an adaptive impedance control approach for torque-controlled manipulators, while the Second strategy is an adaptive admittance controller for position-controlled manipulators. The proposed controllers are very general and computationally efficient since they do not require knowledge of the manipulator dynamic model or parameter values of the manipulator or the environment, and are implemented without calculation of the inverse dynamics or inverse kinematic transformation. It is shown that the control strategies are globally stable in the presence of bounded disturbances, and that in the absence of disturbances the ultimate bound on the size of the controller errors can be made arbitrarily small. The capabilities of the proposed control schemes are illustrated though laboratory experiments with a Robotics Research Corporation Model K-1207 redundant manipulator.