A Control Model for Following Target Inclination Angle in Lateral Direction for Omni-Directional Low-Floor Mobility

The purpose of this research is to develop an omnidirectional low-floor mobility. The mobile platform and the interface have already been developed. The height of the mobile platform is 37 mm from ground to the boarding surface. Omnidirectional movement is realized by using four mecanum wheels. This mobility utilizes sway of the center of gravity of the users. In order to operate this mobility, the users voluntarily tilt their bodies. This body inclination is estimated from the load distribution information of eight load cells installed on the boarding surface of this mobility. This enables forward-backward, lateral, and turning movements. However, the motion of this mobility is oscillatory, because inertia of this mobility causes unintended human body movements, which are input to the interface. In this research, in order to solve this problem, the authors introduce not only an inverted pendulum model but also a human postural control model. In order to change the body inclination voluntarily to operate this mobility, it is indispensable for a human postural control model to be able to follow an arbitrary target inclination angle, not just an upright state. The authors have now achieved forward-backward movement. In this paper, the authors propose a control model for following target inclination angle in lateral direction. First, a control model for maintaining an upright posture is introduced. Next, the authors conduct a body postural maintenance experiment in lateral inclination. A model is identified as a control model for following target inclination angle based on the result of this experiment.