A new method of improving the torque of a travelling wave ultrasonic motor

This paper presents a novel method to improve the torque of a travelling wave type ultrasonic motor by sandwiching a rotor between two stators. By this method, it was tested with two independent travelling wave ultrasonic motors and observed that the resulting torque was nearly doubled. The design of such motor is also discussed in detail. By introducing a gap between the stator and the rotor in the design (to make it friction free), two or more of such motors can be linked together to realize multifarious torque of very high values. We strongly believe that the improved torque characteristics with other salient features of ultrasonic motors would revolutionize the actuator arena and pave a way for further miniaturization.