Design of Translation Rotary Ultrasonic Motor with Slanted Piezoelectric Ceramics

We designed and manufactured a multi-degree-of-freedom (MDoF) ultrasonic motor (USM) by using a single actuator. Although there have been numerous MDoF USMs reported in the literature, only a few of them cover the combined rotary and translational motions in a cylindrical-joint type configuration. Combining these two motions in one joint and controlling this combined motion through a novel USM is the main aim of this work. Here, we use smooth impact drive method (SIDM) with two distinct modes obtained at two distinct frequencies by the help of slanted ceramics and uneven square shaped excitation signals. The translational-rotary dual-mode motor can be driven by single source. The prototype of the motor (5 mm diameter, 25 mm total length) has 5 mm/s translational and 3 rad/s rotary speed under 4 mN blocking force, when the input signal is 20 Vp-p square wave. (C) 2011 The Japan Society of Applied Physics