Abstract

Here, a dual stage PI-PID controller is designed toward independent control of the velocity and orientation angle of a differential drive mobile robot. The control scheme uses real-time measurements of the kinematic variables of the mobile robot and measurements of its orientation angle, considered to be received through a wireless network introducing communication delays between the respective sensor and the controller. Based upon the linear approximant of the non-linear model of the robot, two independent PI controllers are designed toward regulation of the angular velocities of the wheels. Based upon the inner closed-loop system, a multivariable PID controller is designed for stability, independent regulation of the velocity and the orientation angle of the vehicle, and asymptotic command following. Determination of the controller parameters is performed in two stages, using a mixed analytic/metaheuristic approach. The performance of the proposed control scheme is illustrated through simulations.