A piezoelectric disc-shaped motor using a quasi-static walking mechanism

A compact piezoelectric motor that comprises good positioning capabilities has been developed. The stator is manufactured with a multilayer structure that lowers the driving voltage to levels that can be provided by the onboard electronics of a future robot application. The motor exploits a walking mechanism by using three bimorphs to move the rotor in a stepwise manner. Height errors between bimorph tips and stator body stemming from the manufacturing process are recognized and their effects on the motion performance is documented and described. With increasing normal force on the rotor several artifacts in the motion pattern are suppressed enabling a motion performance with high resolution. The maximum torque of the motor is 80 mu N m at a drive voltage of 50 V and a normal force of 1.15 N.