パラレルワイヤ駆動機構を用いた人体の転倒実験装置: 座位での転倒評価の検討

摘要

健常者に接客易であっても，障害者にとって転倒を生じやすい動作は日常多々あり，いったん転倒を生じてしまうと，その後の危険回避や起き上がりなどは非常に困難である.また，高齢者にとって転倒は骨折の危険性が高く，軽症であっても大きな精神的不安を与える.そこで，転倒のし易さ，回避能力等をあらかじめ評価し，転倒予防のための訓練や，注意を促すことは重要である.しかし，転倒に関する実験時には，被験者が実際に転倒し負傷してしまうようなことは絶対に避けなければならない.%This study describes an equipment to evaluate potential of fall of human in seated position. The equipment can make a subject fall safely by supporting the upper body with a wire parallel mechanism. Therefore, the equipment can measure behavior of a subject at fall moment and obtain evaluation data of fall behavior. The wire parallel mechanism consists of four wires connecting the base chair to the output link and can generate spatial 3D0F motion. The output link is attached to the thorax of a subject so as to support and control 3D0F motion of the upper body. Each wire has strain-gages to detect its tension. Furthermore, a force-plate is set on base chair to measure the center of pressure (COP) for comparison. The equipment uses measured wiretension, posture of the wire parallel mechanism and COP as evaluation of fall. The wire-tensions change sharply at fall moment and the posture of the mechanism show the tendencies of potential of fall of a subject clearly. Further human body can be supported by the wire parallel mechanism after falling. Thus, it has been confirmed that the proposed equipment can measure potential of fall of human safely.