Mathematical modeling for omni-tread type snake robot

This article presents an omni-tread snake robot, Caleb III, that designed to locomote on narrow space and rough terrain. The Caleb III comprises three segments, which are linked to each other by 2 degrees of freedom joints for the pitch and yaw motion. Moving track on all four sides of each segment assures propulsion even when the robot rolls over. The 2 D.O.F. joint is actuated by 2 servo motors which produces sufficient torque to lift the one leading or trailing segments up and overcome obstacles. This paper applies articulated steering technique to get Caleb III´s kinematics model. We simulate the robot motion by the proposed kinematic model. And with the same parameters of the simulation we manage several types of motion experiments. Through the experiments we obtained the robot´s Cartesian coordinate(x, y) and orientation by the image processing technique. And we compare the real robot´s experimental results with the simulation results in the case of a straight line motion, a right turn motion and a left turn motion.