Soft sliding mode controller design for a class of singular link manipulator by disturbance compensation

Aiming at singular property for a class of link constrained manipulator, the design of soft sliding mode controller is considered by disturbance compensation in this paper. First, a singular system model of a three-link manipulator is established by the constraint equations and the force descriptions. Then, a dynamic switching function is given and a novel discrete singular exponential reaching law with dynamic disturbance compensation is designed. Finally, soft sliding mode controller for three-link constrained manipulator with uncertainties is discussed by the proposed discrete reaching law. Moreover, it can drive the manipulator system to reach the switching band in finite time and remain on the switching plane. The reason of system chattering will be analyzed and the width of the switching band will be decreased by the proposed controller.