Tests of a Non-contact Piezoelectric Motor Modulated by an Electromagnetic Field.

For improving the service life of piezoelectric motors and the performance of non-contact piezoelectric motors, a novel non-contact piezoelectric motor modulated by electromagnetic field is proposed. This type of piezoelectric motors uses an electromagnetic field to modulate the reciprocating vibrations of a piezoelectric drive mechanism to form the step motion of the rotor. The working principle and structure design of the piezoelectric motor are described in detail. A prototype motor is manufactured and the test system of output characteristics is established. An experiment of the output characteristics were carried out, for exploring the driving scheme, under different parameters of the drive signals. The results state that the proposed motor has a rotational speed of 0.038rad/s, step angle of approximate 1°, and output torque of 6Nmm under the drive voltage of 150V, frequency of 3Hz, and modulation voltage of 7V.