Development of gait measurement robot using laser range sensor for evaluating long-distance walking ability in the elderly

Falling is a common problem in the growing elderly population and fall-risk assessment systems are needed for community-based fall prevention program. In particular, gait measurements such as several-meters walk tests are carried out in community health activities. To evaluate the walking ability of the participant, it is necessary to measure foot contact positions so that the walking parameters such as stride length can be used for fall-risk assessment. However, the conventional measurement systems are difficult to install for use in community health activities because of their scale, cost and constraints of the measurement range. Therefore, we propose a gait measurement robot (GMR) using laser range sensor (LRS) for a long-distance walk tests. From the experimental results with young people, it was confirmed that the GMR could measure the both leg trajectory and the foot contact positions. However, in the case of the elderly especially, a false tracking is likely to occur due to the narrow stride. In addition, the GMR calculates the foot contact positions by analyzing the estimated position and speed of each leg. In the case of the elderly, there is a possibility that the GMR cannot detect the foot contact correctly because the walking speed is likely to be slow. In this study, we carry out the seven-meter straight walk tests with the elderly people using a stationary LRS for the advance verification of measurement in the elderly with the GMR. We verify the leg tracking and foot contact detection using a stationary LRS in the elderly compared with the video analysis.