Development of Parallel Two-wheel Vehicle with Lower Gravity Center of Vehicle Body

This paper presents an advanced parallel two-wheel vehicle which has lower gravity center of vehicle body. The gravity center is assigned at the lower position than the wheel axis. Therefore, the vehicle has a structure of the pendulum, and enables the vehicle body with the passenger to always keep the stable posture, even if the vehicle is in the power-off or control-off condition. And, 2-DOF joystick which has operation with backand-forth direction and rotation is applied to the proposed vehicle. The elderly or handicapped passenger can operate easily the vehicle by this joystick. Moreover, in order to suppress the sway of the vehicle body as a pitching oscillation while driving the vehicle, the sway suppression control system with an active mass damper system is proposed in this paper. The control system is designed by a backstepping method. The effectiveness of the proposed sway suppression control system with the active mass damper system is verified by the experiments using the proposed parallel two-wheel vehicle with lower gravity center.