A single-modal linear ultrasonic motor based on multi vibration modes of PZT ceramics.

We have developed a single-modal linear motor which contains two kinds of PZT ceramics. The linear motor works by exciting the transverse vibration mode of the PZT ceramic on the upper surface of stator elastomer and the shear vibration mode of PZT ceramics at two ends simultaneously. The operation principle of the motor is analyzed in detail. And the rule of the driving foot amplitude varies with the size of the end protruding structure has been further researched by FEM analysis. The prototype is manufactured, and its operating characteristics are experimentally studied and analyzed. The no-load velocity and the maximum output force are tested to be 169.4 mm/s and 1.1 N, respectively. The results show that extra arrangement of PZT ceramics which works on shear vibration mode can efficiently improve the output of motor.