A rod type linear ultrasonic motor utilizing longitudinal traveling waves: proof of concept

Abstract

This paper proposes a non-resonant linear ultrasonic motor utilizing longitudinal traveling waves. The longitudinal traveling waves in the rod type stator are generated by inducing longitudinal vibrations at one end of the waveguide and eliminating reflections at the opposite end by a passive damper. Considering the Poisson’s effect, the stator surface points move on elliptic trajectories and the slider is driven forward by friction. In contrast to many other flexural traveling wave linear ultrasonic motors, the driving direction of the proposed motor is identical to the wave propagation direction. The feasibility of the motor concept is demonstrated theoretically and experimentally. First, the design and operation principle of the motor are presented in detail. Then, the stator is modeled utilizing the transfer matrix method and verified by experimental studies. In addition, experimental parameter studies are carried out to identify the motor characteristics. Finally, the performance of the proposed motor is investigated. Overall, the results indicate very dynamic drive characteristics. The motor prototype achieves a maximum mean velocity of 115 mm s−1 and a maximum load of 0.25 N. Thereby, the start-up and shutdown times from the maximum speed are lower than 5 ms.

A Novel Traveling Wave Sandwich Piezoelectric Transducer With Single Phase Drive: Theoretical Modeling , Experimental Validation and Application Investigation

“…Using the TMM, a complex system can be divided into many simple and continuous elements, such as beams, rods, or plates [20][21][22]. Then the independent transfer matrix model can be described for each element according to the basic wave motion equations and the arbitrary harmonic boundary conditions [23]. Through transfer conditions, the overall transfer matrix model of the entire system can be calculated by combining the independent transfer matrices of all discrete elements.…”

“…Longitudinal vibration is the major vibration stimulated in the sandwich composite beam, therefore, the transfer matrix model of each discrete element in this beam must first be developed. In our previous work [23], [25][26], the longitudinal vibration transfer matrix model of the elastic beam has been presented as:…”

“…Due to the fact that each group of PZT elements operates at their d33 vibration mode to produce the longitudinal vibration, its transfer matrix model (see in figure 4) must simultaneously include the mechanical and electrical coupling properties [23][24][25][26], as written:…”

A Traveling-Wave Linear Ultrasonic Motor Driven by Two Torsional Vibrations: Design, Fabrication, and Performance Evaluation

“…Different from electromagnetic motors, they possess the merits of quick response, self-locking at the power-off state, and absence of electromagnetic radiation [4][5][6]. In particular, linear USMs are potentially applicable to some electromechanical system (e.g., precision instruments and optical devices) [6][7][8][9] as some of them have satisfactorily large outputs (e.g., the maximal thrust force is ~50 N and the maximal output power is >20 W) [10][11][12][13]. However, their thrust force densities and/or power densities are generally not high enough; this probably deteriorates the controllability of electromechanical system [14,15].…”

Dispersed operating time control of a mechanical switch actuated by an ultrasonic motor

“…During the last few decades, piezoelectric actuators and ultrasonic motors have been widely employed in many fields including micro-positioning [1], semiconductor manufacturing [2] and biomedical applications [3]. Particularly, ultrasonic motors are widely used for variable apertures [4], optical cross-connect switches [5] and circuit breakers [6].…”