Development of a holonomic omnidirectional vehicle driven by a spherical motor and proposal of a spherical deceleration driving method

This paper presents a prototype of holonomic omnidirectional moving vehicle driven by a spherical motor that rotates in all directions. This paper also proposes a method called spherical deceleration driving method that can increase the driving torque by tilting the rotation axis of the spherical motor. Experimental results to evaluate the moving performance of the prototype vehicle by the spherical deceleration driving method show that the measured driving forces are almost coincident with the theoretical values within the range that the driving torque of the spherical motor does not exceed the maximum static frictional force between the motor surface and floor. In addition, the driving force can be increased up to about twice the value at the inclination angle of 0 °. On the other hand, the measured moving speeds are well agreed with the theoretical speeds if the slip between the surface of the rotor of sperical motor and road surface does not exist.