Fuzzy sliding mode control for robotic manipulators based on systematic state

In this paper, a novel fuzzy sliding mode controller for robotic manipulators is proposed. The use of a boundary layer in sliding-mode control has been a common technique to reduce chattering of the control input. However, different choices of the boundary layer width lead to conflicting effects: a large/small width of the boundary later can more/less effectively alleviate the chattering of the control, but lead to less/more accurate control results. This note applies fuzzy logic to adjusting the width of the boundary layer based on the state. The method can effectively eliminate the chattering and ensure almost perfect control accuracy at the same time.