In Japan, where aging is faster than ever, the shortage of a young labor force is a serious problem, especially in the nursing field to support care recipients and in the primary industrial field to support heavy labor. Hence, the use of power assist devices that mechanically reduce the burden on the body is drawing increasing attention. This study focuses on the lifting motion, which can be performed by two methods, the squat method and the stoop method; the former involves bending the knee and the latter involves using the waist. The squat method is recommended because the burden on the waist is lower than that in the case of the stoop method. Currently, many types of wearable power assist devices to reduce the burden on the waist have been developed; however, they are based on the stoop method because of their assist mechanism. In this study, we developed a non-wearing type pneumatic power assist device that allows the squat method. After describing the basic concept and assist mechanism, the support effects are confirmed through experiments.

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