TRAJECTORY TRACKING WITH PID AND SLIDING MODE CONTROL FOR DIFFERENTIAL DRIVE MOBILE ROBOTS

Abstract

Differential drive mobile robot (DDMR) is the most commonly used autonomous land vehicle type for small scaletrajectory planning and tracking applications. In this study, two driven wheeled and one castor wheel includedDDMR model is used for kinematic and dynamic modelling. In trajectory tracking stage, kinematic basedbackstepping control (KBBC) is operated in order to reduce robot pose (position and orientation) error viakinematic model of the system. Sliding mode control (SMC) and proportional–integral–derivative controller (PIDcontrol) are separately implemented to the dynamic model for controlling dc motors of wheels which is requisitefor tracking of given reference trajectory. Mathematical modeling of the DDMR and control strategies aresimulated in software and results demonstrate that both SMC and PID control strategies with KBBC providerobust, smooth and accurate trajectory tracking performance. Because of the better SMC error performance in thisstudy, it is foreseen that SMC can be better choice for more complex trajectory and environment conditions.