Speed and point-to-point control for trajectory tracking of a Skid-Steered Mobile Robot

This paper presents the development of a motion control scheme of a Skid-Steered Mobile Robot (SSMR). The System Architecture used in this work consists in four systems: Trajectory Tracking, Point-to-Point Control, Speed Control and Pose Estimation. These four systems work together to perform autonomous navigation. The Speed Control System consists in a digitally designed R-S-T control, for both the left and right side of the mobile robot. This configuration allows to obtain similar transient responses, ensuring the achieving of the reference speed. Using wheel encoders and an IMU, the Pose Estimation System obtains the pose of the robot, based on the kinematics. The Point-to-Point and the Trajectory Tracking System provide the robot with the necessary speeds each side must execute, in order to reach the desired coordinated points. Experimental results on a real world robotic platform show the reliability of the method to perform trajectory tracking.