A cryogenic ultrasonic actuator using a torsional transducer

In this study, a torsional transducer type ultrasonic motor which realizes the continuous rotation and the positioning of the angle in cryogenic temperature has been fabricated and evaluated. In the cryogenic temperature environment, the performance of the transducer falls. In order to drive the motor at cryogenic temperature, the torsional transducer is designed to generate the resonant stick-slip drive. The transducer can perform the resonant stick-slip drive by combining the first and the second vibration modes. The ultrasonic motor using the transducer was evaluated. The rotation speed and the starting torque are 111 rpm and 0.75 mNm at 4.5 K.