Position control of micro-cylindrical ultrasonic motor

This paper evaluates the dynamic performances of cylindrical ultrasonic motor (CUSM) under the excitation of two sinusoidal signals for both speed and position control application. Such a study is useful for the design of an effective servo control scheme for the CUSM. In particular, it is important to understand the effect of the three possible control variables, namely, voltage amplitude, driving frequency and phase difference of the two excitation sinusoidal voltage waveforms. From the experimental results obtained with a 10 mm diameter and 30 mm long CUSM, it can be concluded that the voltage amplitude control provides high dynamic and steady-state performances for speed/position control of the CUSM.