AN ADAPTIVE VARIABLE STRUCTURE MODEL FOLLOWING CONTROL DESIGN FOR ROBOT MANIPULATORS

An adaptive variable structure model following control design is presented for the nonlinear robot manipulator system. The controller does not require any knowledge of a nonlinear robotic system and does not necessarily need the occurrence of a sliding mode at each individually stable discontinuity surface. It thus greatly reduces the complexity of design. In the closed loop, the joint angles asymptotically converge to the reference trajectory with a prescribed transient response. The problem of chattering is reduced by the introduction of a boundary layer.