Holonomic and omnidirectional vehicle with conventional tires

A new type of holonomic omnidirectional vehicle which consists of wheel mechanisms without free rollers but with conventional tires is presented. We first present the concept of a new driving wheel mechanism with a tire in the conventional style such as a rubber tire or a pneumatic tire, an "offset steered driving wheel". The configuration of the wheel has an offset distance between the wheel axle and the steering axle along the direction of wheel travelling. We then describe the kinematics and the control method of the offset steered driving wheel to provide an omnidirectional and holonomic capability for a vehicle by actuating the wheel axis and the steering axis independently. The wheel is a nonholonomic system, and we introduce a control strategy to avoid a nonholonomic constraint. Simulation results of the single driving wheel and the two-wheeled vehicle are performed to test the control method. The concept of offset steered driving wheel is implemented and tested on a prototype of the holonomic omnidirectional vehicle. Experimental results demonstrate high mobility of the vehicle prototype.