ADAPTIVE STABILIZATION AND TRACKING CONTROL OF ELECTRICALLY DRIVEN MANIPULATORS

This article presents two new adaptive strategies for motion control o f uncertain rigid-link, electrically driven manipulators. The first co ntroller is a position regulation scheme that ensures (semiglobal) asy mptotic convergence of the position error if no external disturbances are present, and convergence to an arbitrarily small neighborhood of z ero in the presence of bounded disturbances. It is shown that the regu lation scheme can be modified to provide accurate trajectory tracking control through the introduction of adaptive feedforward elements in t he control law; this second control strategy retains the simple struct ure of the first controller and ensures arbitrarily accurate tracking in the presence of bounded disturbances. Each of the adaptive schemes is computationally efficient and requires virtually no information con cerning either the manipulator or actuator models. Computer simulation results are given for a PUMA 560 manipulator and demonstrate that acc urate and robust motion control can be achieved by using the proposed controllers. Experimental results are presented for an IMI Zebra Zero manipulator and confirm that the proposed approach provides a simple a nd effective means of obtaining high performance motion control. (C) 1 996 John Wiley & Sons, Inc.