支持面の水平移動時における立位人体のモデリングと制御

Abstract

This study focuses on the balance modeling of human body on frontal plane. For practical use, the model should be effective when its support surface moves to horizontal direction in low frequencies below 1 Hz. The frequency range allows us to regard the mechanism of the model as a single degree of freedom system. Then the balance model can be expressed as a transfer function whose input is acceleration of the support surface and output is moment acted from support surface to hold human body balance. To obtain the transfer function model being stable, three characteristic roots of the model were estimated from impulse response test. Finally, the third-order transfer function model was derived from frequency response test. The results of frequency response test indicated that they are reproduced and acceleration of the support surface and posture of human body become inverted in low frequency range (< 0.2 Hz). To verify the effectiveness of the identified models, state estimation based on full-order state observer and full-state feedback control to keep the subject 's balance easily were applied in experiment. Although it is possible to estimate and control the state variables of human body, the accuracy is insufficient to aid the balance control of human body standing on moving board. The result indicates that dimension of the model should be higher than third order in our future work.