Japan has an aging population, and the number of patients with physical impairment is increasing owing to aging and accidents. A contracture is a state in which joint movements are worsened owing to the hardening and loss of elasticity of the surrounding soft tissue such as muscle and skin, when a patient is immobile or bedridden for long durations. In particular, finger and wrist contractures can cause many inconveniences in daily life. Thus far, some rehabilitation devices have been developed. A power assist glove extends the finger but is difficult for patients to wear. This study focuses on wearability and risk avoidance, and develops a device with two parallel sticks that are driven by pneumatic actuators to simulate the motion of a physical therapist. After verifying the fundamental control performances, the safety function based on the estimated force applied by the patient and the improvement of effectiveness in rehabilitation using a USB camera are discussed.

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