Department of Mechanical Engineering,Sharif University of Technology
This paper presents an effective approach for kinematic and dynamic modeling of high mobility Wheeled Mobile Robots (WMR). As an example of these robots, the method has been applied to the CEDRA rescue robot, which is a complex, multibody mechanism. The model is derived for 6-DOF motions, enabling movements in x, y and z directions, as well as for roll, pitch and yaw rotations. Forward kinematics equations are derived using the Denavit Hartenberg method and Jacobian matrices for the wheels. Moreover, the inverse kinematics of the robot are obtained and solved for the wheel velocities and steering commands, in terms of the desired velocity, heading and measured link angles. Finally, the dynamics of the rover mechanism have been thoroughly studied and analyzed. Due to the complexity of this multi-body system, especially on rough terrain, Kane's method of dynamics has been used to model this problem. The proposed approach and method can easily be extended to other mechanisms and rovers.