Backstepping based trajectory tracking control of a four wheeled mobile robot

For a four wheeled mobile robot a trajectory tracking concept is developed based on its kinematics. A trajectory is a time-indexed path in the plane consisting of position and orientation The mobile robot is modeled as a non holonomic system subject to pure rolling, no slip constraints. To facilitate the controller design the kinematic equation can be converted into chained form using some change of co-ordinates. From the kinematic model of the robot a backstepping based tracking controller is derived. Simulation results demonstrate such trajectory tracking strategy for the kinematics indeed gives rise to an effective methodology to follow the desired trajectory asymptotically.