An ultrasonic actuator with multidegree of freedom using bending and longitudinal vibrations of a single stator

An ultrasonic actuator with multi-degree of freedom with a single stator is proposed and has been constructed for trial. Three sets of piezoelectric elements are installed in the stator, and two bending vibrations perpendicular to each other and a longitudinal vibration can be excited independently with three separate electrical ports. A spherical rotor is revolved on all the three axes by the combination of these vibrations.