Standing posture analysis of a human on a four-wheel stand-up-type personal mobility vehicle

Abstract

In recent years, personal mobility vehicles (PMVs) have attracted huge attentions and widely developed. Compact PMVs can move through narrow spaces and they are expected to be used in pedestrian spaces. In this study, we aim to develop a four-wheel stand-up-type personal mobility vehicle for people who cannot walk far distantly because of the pain of foot or waist although they are able to walk for a short distance. The coupled model of human and vehicle is constructed by using multibody dynamics. In the model, the vehicle is expressed by one rigid body. The wheels, body, and handle are considered as a rigid body together. A human is expressed by 8 rigid bodies (foot, lower leg, femoral, body, head, upper arm, lower arm, and hand). The vehicle of the coupled model is accelerated in the numerical simulations. The behaviors of the center of gravity of a human with and without handle constraint are analyzed. As the result of the parametric study, it is found that the center of gravity movement is smaller when the value of the maximum acceleration and the acceleration time are small. It is also found that as the angle of the upper arm becomes large, the movement of the center of gravity is decreased.