Cimev: Caster-wheeled Independent- Motor-driven Electric Vehicle, Its Design and Control as a Future Mobility Solution

This paper presents a novel chassis structure for advanced mobility platforms, using caster wheels with disturbance observers, and independent driving motors. The system consists of two independent driving wheels and two caster wheels. The proposed configuration enables the vehicle to have: a low mechanical stiffness against the direct yaw moment input because caster wheels are free to rotate; and high static stability because of the four wheels having a large base geometry. In addition, by introducing disturbance observers, the vehicle was given enhanced mobility and safety characteristics. A number of advantages, which include small-radius turning, under-steer gradient control, load transfer estimation, of the proposed system are shown and discussed with experimental results throughout the paper.