| 摘要 |
PURPOSE: To provide a multi-degrees of freedom by means of less channel control so as to accomplish reduction in weight and increase in rigidity of an actuator by arranging a freedom-degree selecting means, by which one of a rotor and a stator in a ultrasonic motor unit is optionally stopped while the other can be rotated. CONSTITUTION: When a stator braking spring 8A in an upper flange 4A is excited and heated so as to be expanded, a slidet 7A is pressed to a stator 2 so as to apply braking. Under this condition, after an ultrasonic motor unit 1 is excited so as to rotate a rotor 3 in the optional direction and an actuator is bent in the desired direction, a revolute joint driving SMA 12 is heated and expanded so that a coil spring 10 is bent at an angle required as a frame. For performing rotational work around the axis, excitation to the spring 8A is stopped, the stator 2 is freed, and a spring 8B, which is built in a lower flange 4B and made of a rotor braking SMA, is excited and heated, so that a slider 7B is pressed to the rotor 3 so as to apply braking, and then, the ultrasonic motor unit 1 is excited and the stator 2 is rotated. |
