A ROBUST TRACKING CONTROL SCHEME FOR RIGID ROBOTIC MANIPULATORS WITH UNCERTAIN DYNAMICS

In this paper, we develop a new robust tracking control scheme using a variable structure compensator for the feedback control of rigid robo tic manipulators. It is shown that a robotic manipulator is treated as a partially known system, and the known dynamics is separated out to perform a linearization. Then a nominal feedback controller is designe d using a nominal system model and a variable structure compensator is introduced based only on a system uncertain bound to eliminate the ef fects of the unknown portion of the plant. Using this scheme, the clos ed loop system behaves with a high degree of robustness with respect t o large uncertain dynamics and guarantees that the output tracking err or asymptotically converges to zero with desired transient error respo nse on the sliding mode. A simulation is given in support of the propo sed control scheme.