Actuator device and method for driving the same

An actuator device, comprising:

• an actuator;
• and
• an AC power supply capable of applying a high-frequency voltage to the actuator,
• wherein
• the actuator comprises a flexible tube formed of a polymer, an inner electrode, and an outer electrode;
• the inner electrode is in contact with at least a part of an inner periphery of the flexible tube in a cross section perpendicular to a longitudinal direction of the flexible tube;
• in the cross section, a part of an outer periphery of the flexible tube is coated with the outer electrode;
• in the cross section, the part of the outer periphery of the flexible tube coated with the outer electrode faces the at least the part of an inner periphery of the flexible tube which is in contact with the inner electrode so as to interpose a part of the flexible tube therebetween;
• and
• the AC power supply, in operation,
• applies the high-frequency voltage having a frequency of not less than 1 MHz to the actuator to deform the actuator in a direction from the inner electrode toward the outer electrode in the cross section, and
• stops the application of the high-frequency voltage to the actuator to return the actuator to the original position thereof.