Abstract
This paper demonstrates a new type of compact ultrasonic motor that operates using a wobbling mode of motion. The motor was driven by a piezoelectric composite stator that consisted of a hollow metal cylinder whose outside surface was flattened on two sides at 90° to each other, upon which two rectangular piezoelectric plates were bonded. A wobbling motion was generated at both ends and at the center of the stator upon application of a sinusoidal voltage to each piezoelectric plate (which were phase shifted by 90° with each other). Results showed that the flexural displacement at the stator's center was ∼ 4 × that at its ends. Consequently, the stator could drive a rotor using a center wobbling motion. Our prototype motor had a significantly higher driving force than conventional end driven stators. The prototype was 4.7 mm in diameter and 20 mm in length, having a rotor 20 mm in diameter. The prototype operated at 46 kHz, had a maximum torque output of ∼ 50 mNm, and had a no-load rotational speed of 70 rpm in both directions. The prototype was also found to be suitable for precision actuation applications.
Get full access to this article
View all access options for this article.