Six DOFs Motion Platform using Omni-Spherical Wheels

This paper presents the development of a six degree-of-freedom (DOF) motion platform based on omni-spherical wheels. Various motion platforms have been developed for motion realization, but there are limits such as workspace and rigidity. The motion platform developed here is capable three DOFs unlimited rotation and three DOFs translation. The omni-spherical wheels motion platform is designed to improve the motion control as well as realization of unlimited rotation and high rigidity. The motion platform in this paper has symmetric design but additional driving actuators compared to the existing. However, it can provide large workspace about linear motion with generation of large linear and angular velocity. The design is still compact and lightweight with one additional stage offering larger motion capability. Kinematic and dynamic analysis of the platform is investigated to provide a basis of motion and demonstrated from numerical simulation. The experiment is implemented by using actual prototype model. Both results from numerical simulation and experiments show the design feasibility and motion capability.