Fuzzy sliding mode control of a fast parallel robot

Abstract

Robustness is a very important feature of robot controllers. Obviously, dynamic control is not the good way to obtain the best robustness performance, especially when the payload is unknown. Moreover, this kind of control laws are not able to compensate for Coulomb friction. Our approach is based on the variable structure control (VSC) with sliding mode, but it is well known that VSC is unstable for physical sampled systems. Therefore, the concept of fuzzy logic is used to implement fuzzy sliding mode control on our six-degree-of-freedom fast parallel robot. Both simulated and real experiments are reported in this paper.