Motion Characteristic Analysis Of A Novel Omnidirectional Mobile Robot

Omnidirectional mobile robot has been extensively researched in the field of robots because of its full three degrees of freedom on the motion plane. It can run on the planar surface freely and realize the omnidirectional movement without changing its posture. Consequently, from movement characteristic aspect, its advantages far outweigh the advantages of conventional robot. It has been widely used in some congested sites.In this paper, many kinds of omnidirectional mobile robots have been extensively studied. Then the basic structure of a novel omnidirectional wheel is introduced in detail. The kinematics model of an omnidirectional mobile robot with MY(Mutual YoYo) wheels is built to analyze its performance on vibration, control and errors that are caused by MY wheels. It demonstrates that the robot can still realize the omnidirectional motion. Trajectory errors, which are induced by vibration in the motion, are reduced distinctly by the proposed control method of both optimized contact distance and improved rotational speed of MY wheel. The movement effects of tri-wheels platform and four-wheels platform were compared for getting optimal structure. It can improve the stability of movement for the robot by employing sinusoidal control law to control the angular velocity of MY wheel reasonably. Simulation results are provided to demonstrate the performance of proposed approaches.In order to achieve the optimal control of the robot, its dynamics model is built by the use of Lagrange-d’Alembert equation. The driving torques are acquired through dynamic simulation in the case of linear and circular movement.Kinematics and dynamics analysis of the omnidirectional mobile robot play an extremely important role in robot control and practical application.