Abstract
An inverted pendulum vehicle controlled by the movement of the driver’s center of gravity (COG), such as Winglet or Segway is one of the Personal Mobility Vehicles (PMV). PMV is sometimes expected to be used in pedestrian spaces. When a driver brakes suddenly, the driver has to move the COG behind largely and has the potential to lose his balance according to the characteristics of the vehicle control. Therefore, we aim to achieve the vehicle control that is friendly to the driver in emergency. In previous study, the coupling model of the vehicle and a human is built using Multibody Dynamics. In this study, we use the previous model and propose an automatic braking system that is put into practice by changing two feedback torques (① T1 = -K1θbody - K2ωbody, ② T2= -K′1θbody - K′2ωwheel - K′3ωbody). θbody is the angel of the vehicle body, ωbody is the angular velocity of the vehicle body and ωwheel is the anglular velocity of the wheel. K1, K2, K′1, K′2, K3 are feed back gains for each variables and are derived from optimal control. T1 is used in the normal running. T2 is used in emergency to stop quickly and three control gains were compared. First, in the numerical simulations, the effect of the automatic brake and the brake by a driver were compared. As the result, it was found that one of three condtions of the automatic brake gains was more effective in the quick deceleration and the stability of a driver. Second, we carried out experiments to confirm the effectiveness of the proposed method by using feedback gains corresponding to the numerical simulation. As the result, we confirmed that changing the feedback torques at the time of braking enables the inverted pendulum vehicle to stop quickly.
