Abstract:
The number of lower limb amputations in Japan has recently been increasing. This is due to rising incidence of arteriosclerosis obliterans and diabetes resulting in amput...Show MoreMetadata
Abstract:
The number of lower limb amputations in Japan has recently been increasing. This is due to rising incidence of arteriosclerosis obliterans and diabetes resulting in amputations for elderly people. There are two main types of lower limb amputations: below knee (50%) and above knee (35%). Especially, for patients with above-knee amputation, above-knee prosthesis is commonly applied. However, this type of prosthesis usually comes with higher risks of tripping compared to below-knee prosthesis. Thus, it is more difficult to guarantee safe walking. The result is a low percentage of elderly lower limb amputees using prosthesis. In order to prevent unexpected knee bending, which is the main cause of tripping in above-knee prosthesis, a multi-axis knee joint was developed. It prevents knee bending by moving the instantaneous center of rotation behind weight-load line, by adjusting the links structure at heel contact. However, while this mechanism is functional for preventing knee bending in the stance phase, prevention in the swing phase was not considered. As knee bending in the swing stance also causes stumbling, the risk of tripping and falling remains hiah. In this study, we developed a robot prosthesis that prevents falling by controlling the links position of the knee joint with an actuator based on the state transition and using a finite state machine that models the walking state. By controlling the linkage mechanism, we achieved correspondence to knee bending at every point of the stance and swing phases. Furthermore, we confirmed fall prevention and normal walking motion in experiment to demonstrate the effectiveness of the proposed method.
Published in: 2018 7th IEEE International Conference on Biomedical Robotics and Biomechatronics (Biorob)
Date of Conference: 26-29 August 2018
Date Added to IEEE Xplore: 11 October 2018
ISBN Information: