Design of Multi-DOF Spherical Platform for Omnidirectional Locomotion in Virtual Reality

This paper presents the development of a novel multi-degree of freedom (DOF) motion simulator based on a spherical wheel system. Virtual reality (VR) has gained significant interest due to its broad range of applications, leading to the development of motion simulators. However, the existing simulators are limited in their motion range and speed of operation, and they lack a degree of freedom. In this paper, the design of a VR-spherical platform for an omnidirectional traveling simulator (VR-SPOTS) is presented to overcome the limitations of existing platforms. The proposed platform achieves high-speed operation with unlimited three-DOF rotation by combining a spherical wheel system and roller-gear assembly, resulting in a simpler mechanical structure. The kinematic and dynamic behavior of the platform is analyzed to establish the motion basis. In addition, a control strategy suitable for effective motion including orientation and velocity control is designed. Numerical simulations verify the feasibility and performance of the proposed design and control scheme, demonstrating accurate orientation and velocity control under various operating conditions. VR-SPOTS is expected to have broad applications in human-factor studies, rehabilitation, and human-machine interaction.