Adaptive Control of Free-Floating Space Robot with Disturbance Based on Robust Fuzzy Compensator

Abstract

This paper proposes an adaptive controller for a free-floating space robot (FFSR) in the presence of friction, disturbance and variation of payload based on robust fuzzy compensator. In the micro-gravity environment, the FFSR lacks a fixed base, so the high dynamic coupling between the manipulators and the free-floating base leads to two inherent difficulties, such as non-linear parameterization of the dynamic equation and both kinematic and dynamic parameter uncertainties. In order to overcome these obstacles, we use the fuzzy logic system (FLS) to approximate the nonlinear dynamic function. The proposed controller does not involve any complex calculations, but it is still possible to overcome the uncertainty and efficiently track the desired trajectory of the manipulators in a short time. The stability of the controller is demonstrated, and meanwhile, the structure of the controller is given. Through numerical simulations, the validity of the proposed scheme is also demonstrated.