Simulation of Single Belt Motion in a Spherical Wheel Motor with a Virtual Shaft

A new type of motor is proposed to permit the wheels of an electric vehicle full freedom of driving orientation, using permanent magnets and electric coils. The proposed Spherical Wheel Motor (SWM) structure is composed of a sphere with permanent magnets and a hemisphere with electric coils which interact to generate omnidirectional rotation from electrical energy. The SWM can be operated by controlling each belt, like a conventional brushless DC (BLDC) motor system, by the direction of the coil position. Each belt can generate a torque in a selected direction and cause a transition in the rotation direction by combining the belts' torques. To evaluate the driving feasibility of the proposed structure, electrical and mechanical operation was mathematically emulated in simulation using PSIM. For a SWM with a rotor radius of 50 mm, a belt in the SWM has a torque of 0.08 N.m and a speed of 250 rpm. It is expected that the feasibility of the proposed structure will be demonstrated and implemented as an electric spherical wheel for future mobile applications.