All of us know that motor is a machine which produces or imparts motion, or in detail it is an arrangement of coils and magnets that converts electric energy into mechanical energy and ultrasonic motors are the next generation motors.
In 1980,the world’s first ultrasonic motor was invented which utilizes the piezoelectric effect in the ultrasonic frequency range to provide its motive force resulting in a motor with unusually good low speed, high torque and power to weight characteristics.
Electromagnetism has always been the driving force behind electric motor technology. But these motors suffer from many drawbacks. The field of ultrasonic seems to be changing that driving force.
Ultrasonic motors are characterized by the absence of noise during operation, High torque weight ratio, highly accurate speed and position control etc . The advantages of ultrasonic motors makes them open to a wide range of applications and technologies.
These are operated using ultrasonic vibrations to obtain a driving force, which then drives the motor using friction. When a voltage with a resonant frequency greater than 20kHz is applied to the piezoelectric element attached on an elastic body(stator),the piezoelectric element will expand and contract ,causing ultrasonic vibrations on the stator. The working principle is based on a traveling wave as its driving force.