Fractional order tracking control of a wheeled mobile robot

This work implements two trajectory tracking control systems for a differential drive WMR (Wheeled Mobile Robot). The first control system employs an IO PD (Integer Order Proportional Derivate) controller, while the second uses a FO (Fractional Order) PD controller. The IO PD controller becomes a FO PD controller by making fractional the derivative term. That is, replacing the Laplace operator s by sm, where m is a fractional number between 0 and 1. Experimental results demonstrated that the IO and FO PD controllers ensure posture stability of the feedback control system as well as a good control performance. However, the FO PD control system shown a better tracking of the desired trajectory. WMR kinematics was employed to obtain the required linear and angular velocities.