腰部サポートワイヤを有するテレスコピックブーム型介護リフトのマルチボディダイナミクス解析

<p>Recently, several types of nursing care equipment to aid the lifting and transfer of aged persons have been developed. Especially, rotational boom-type care lifts are used widely because of their simplicity and usefulness. However, such lifts sometimes provide a feeling of uneasiness because during lift-up, the center of the human body moves backward relative to the position of the heel. Hence, in our previous study, we proposed a telescopic boom-type care lift to approximate the trajectory of the lift-up motion of a human standing up naturally. By using a multibody dynamics approach, we showed that the proposed mechanism can achieve nearly natural standing-up motion and requires a smaller force for lift-up than that required by the conventional-type lift. After that, we considered the optimal design of the proposed care lift structure. We proposed an algorithm to seek optimal design parameters that minimize the error between the tip trajectory of the lift and the human chest trajectory measured using a motion capture system. We developed a prototype telescopic boom-type care lift with the optimal design parameters and confirmed that it can reduce the burden on cared-for persons compared with that imposed by the previous design. In this paper, we first re-examine the standing-up motions of elderly people. As a result, it is found that the pelvis of most elderly people is inclined backward and it makes difficult to stand up. Therefore, we propose to add a back support wire into the previously proposed telescopic boom-type care lift. We approximate the cared person by a three link model and combine it with the multibody model of telescopic boom-type lift. After that, multibody dynamics analysis is performed and the effect of the back support wire is investigated.</p>