Mixed Model Based/ANFIS Adaptive Robust Controller with H∞ Criterion Applied to Free-Floating Space Manipulators

This paper deals with the problem of robust trajectory tracking control, with a guaranteedH∞ performance, for free-floating manipulator systems. A control strategy is developed based on the robot mathematical model and a fuzzy adaptive approach. The dynamic model of the free-floating space manipulator is described via the Dynamically Equivalent Manipulator approach. The fuzzy adaptive control law is based on Takagi-Sugeno model, which is proposed to estimate the behavior of parametric uncertainties and spacecraft non-modeled dynamics. An Adaptive Network-based Fuzzy Inference System is applied to generate input membership functions. A nonlinear H∞ controller is formulated in order to attenuate the effects of estimation errors and external disturbances. The proposed strategy does not demand any position, velocity or acceleration value from the free-floating base. Experiments on a fixed-base planar manipulator were evaluated and showed the effectiveness of the proposed approach.