Adaptive Fuzzy Control with Modulated Membership Function Applies to Path Tracking Based on Location System

This paper presents the design and implementation of a three-dimensional (3D) location system to provide accurate location information. The location information is computed by applying Trilateration technique on three sets of collected distance measurements. Trilateration technique is implemented to improve the accuracy of the location system. The 3D system is able to provide accurate locations for path tracking in robot navigation experiments conducted at a large indoor area of our lab. The fuzzy adaptive controller with modulated membership function (FAC_MMF) modulates the fuzzy sets on both the consequent and antecedent parts by adjusting a few parameters. As searching for those parameters in modulated membership functions is done by micro-genetic algorithm, FAC_MMF becomes effective. Since all system experiences uncertainties, a robust controller and a supervisory scaling gain are implemented in a closed-loop nonlinear system to guarantee a stability condition established by Lyapunov function. The AGV controlled experiment by the FAC_MMF is demonstrated to illustrate the effectiveness of the proposed method.