Variable Structure Model Following Control of Robot Manipulators with High-Gain Observer

Abstract

The conventional sliding mode control motion has two phases, i.e., the reaching phase and the sliding phase. However, the invariance of the sliding mode control only applies to the sliding phase on the sliding surface. In the reaching phase, the switching control is applied to provide the robustness but there usually exists chattering. The conventional continuous approximation method can alleviate chattering but spoil the robustness. In this paper, a sliding mode control with global invariance is studied to solve the above problem. On the other hand, velocity sensors are often omitted to reduce the cost and reject measuring noise. In this paper, a Variable-Structure Model Following Control with output-feedback is proposed to solve tracking problems with modelling uncertainties and external disturbances.