Trajectory tracking control for wheeled mobile robots based on a piecewise fuzzy Lyapunov function

A trajectory tracking problem is investigated for wheeled mobile robots with control input constraints and external disturbances. Firstly,the trajectory tracking posture error model is transformed into a T-S fuzzy model. Under this framework and parallel distributed compensation,a design method of constrained H_∞ controllers is developed via the piecewise fuzzy Lyapunov function approach,and the stability conditions of the closed-loop system are also derived. Finally,simulation results are given to illustrate the effectiveness of the proposed method.