サドル支持型免荷装置を用いたトレッドミル歩行訓練における蹴り出し動作のタイミング推定

―骨盤／サドルの運動に着目した間接的アプローチ―

抄録

The combination of the seat-type body weight support (BWS) and active treadmill system is powerful to train a variety of gait functions such as discrete/rhythmic stepping, balance, speed, and symmetry. As a supplementary technology for robot-aided gait rehabilitation, this study aims to explore methods for estimating ankle push-off initiation focusing on pelvic and saddle motion peculiar to saddle-seat-type BWS treadmill walking. The experimental results of explored methods suggest that (1) the timing estimated from transverse pelvic rotation moderately agreed with ankle push-off initiation timing (Spearman's rank correlation coefficient ρ=0.59, p<0.01) and (2) the timing estimated from transverse saddle rotation strongly agreed with ankle push-off initiation timing (ρ=0.67, p<0.01). The utilization of a single IMU sensor requires a minimal setup for identifying ankle push-off initiation, which contributes to reduce time, efforts, and costs in clinical settings.