Development of forearm support-type lift assist system (FOLAS): System design for intuitive assist operation without wearing

In the labor-intensive fields, lifting a heavy object up and down is regarded as a frequently performed motion which imposes a physical strain on workers. Power assist systems are expected to address such a problem. However, conventional systems in the related studies have the disadvantage of either the effort for wearing or specified operation manner, which may prevent them from being introduced to various fields. The objective of this study is to develop forearm support-type lift assist system (FOLAS) that realizes intuitive assist operation without wearing. The design concept, system configuration, and control method of FOLAS are introduced in this paper. Nonrestraint forearm-support structure was first constructed and air cushion that indirectly detects user's maneuvering force through pneumatic pressure sensor was then developed to assist lifting motion without fixing his/her body on the system. Simple force control algorithm which enables a human user to operate intuitively. Experiment on the power assist performance was performed, the results were evaluated by myoelectricity, and we could verify the usefulness of FOLAS as a new type of power assist system.