巻フィルムチューブ式SMA人工筋肉アクチュエータの開発

（改良型モータユニットの特性）

抄録

In this study we aim to realize an actuator that is comparable with a natural muscle from a viewpoint of flexibility, the output force and the responses. We constructed the Shape Memory Alloy (SMA) actuator protected by “a Rolled Film Tube” with the high heat resistance and the high flexibility. A coil spring made of SMA wire with rectangular cross section was acquired at last study. In this study, we made a motor unit with seven coil springs made of SMA wire with rectangular cross section. The main body of the motor unit was inserted into the natural rubber outer tube to prevent coolant leakage. However, the natural rubber outer tube deteriorated quickly and was insufficiently flexible in the axial direction. Therefore, we proposed a coolant recovery system (lymphatic system) that reuses the leaked coolant as lubricant and an open type outer tube that does not require dripproof is adopted. As a result, in present study, the maximum output force was 10.3N and the minimum time constant is 1488ms. Prior to this experiment, as a result of an experiment on one coil spring made of SMA wire with rectangular cross section, the maximum output force was 2.5N and the minimum time constant was 170ms. Therefore, in the near future, the maximum output force of the motor unit can be increased to 17.5N and the minimum time constant can be shortened to about 200ms.