In today’s situation with high needs for care, a transfer work, among various assisting works, produces particularly large physical burden. The burden could result in not only diseases including waist pain but also resignation of care workers. A nursing lift used to reduce the burden lifts up a care receiver by using a wire or mechanical structure, causing sway. The sway not only makes the care receiver uncomfortable but also causes a risk of unintentional collision. To prevent such a situation, carers need to assist care receivers by holding them while simultaneously operating equipment and paying attention to the care receivers, which is not preferable from a viewpoint of work safety. In this study, we experimentally analyzed and discussed sway of a person when he/she is lifted up. On the basis of an analysis result, we propose an automatic control method of dynamical speed change for safe lifting works, which is applicable to ordinary nursing lifts.

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