PD Control with Fuzzy Compensation

In this chapter, the fuzzy system is used to estimate the uncertainties of exoskeleton robots, such as friction, gravity, and the other noises. The online learning rules for the membership functions are obtained from the regulation and tracking errors analysis. The overall closed-loop system with the high-gain observer and the fuzzy compensator is stable if the membership functions are trained by certain learning rules and the observer is fast enough. The theory results are verified by the upper limb exoskeleton, CINVESRobot-1.