Application Of Adaptive Fuzzy Control Of The Manipulator System

Adaptive fuzzy control is a research field which is interactive theory between fuzzy control and adaptive control. Adaptive fuzzy control has recently attracted increasing attention from control circles, because the system of adaptive fuzzy control can not only improve system performance by modifying itself rules but also has quick convergence speed and robust. It is very suitable to model and control for nonlinear and multiplicity systems.Firstly, an adaptive fuzzy identification method for a class of nonlinear dynamic system was presented based on universe approximation of fuzzy logic system. The parameters of fuzzy identification can be adapted by identification on line. It is proved that the proposed method can reduce the identification error by adjusting the value of designed parameters.Secondly, adaptive fuzzy control methods are presented for a class of uncertain SISO nonlinear systems and MIMO nonlinear systems. For SISO nonlinear systems, two fuzzy logic systems are used to approximate unknown functions and inverse of unknown functions. For MIMO nonlinear systems, the matrix, which is composed of fuzzy logic systems, is used to approximate the matrix inverse in the controller in order to avoid the controller singularity problem. In the two situations, the error compensator is used to eliminate approximations errors. It is proved that the proposed schemes not only guarantees the boundedness of all signals in the closed-loop system, but also makes the tracking error converge to a small neighborhood of the origin.Lastly, adaptive fuzzy control method for MIMO nonlinear systems is used to control dynamic model of robot. Simulation results demonstrate the effectiveness of this method.