The high rate of lower back pain in workplaces that involve lifting heavy loads is a worldwide problem. Various lower back assistive devices have been developed to reduce the lower back burden during lifting work; however, they often have issues such as weight, workability with them and more, and are not used continuously in workplaces after purchasing. In this study, we conducted parameter adjustments of the pneumatic spring using a single-acting air cylinder to develop a device capable of assisting in lifting tasks. We performed requirements analysis, modeled lifting movements, examined various parameters of the assistance device, and designed skeletal structures and attachment components to meet the target weight.

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