Dynamic Characteristics of Tiny Ultrasonic Linear Actuators

Tiny ultrasonic linear actuators (TULAs) are used in many industrial applications and a full characterization of their dynamic behavior is needed. This paper presents a detailed theoretical-experimental study of TULAs. The general structure and operation principle of TULAs are introduced. The actuator dynamics is then described using a simple piezoelectric model. In practice, TULAs are most often used as actuators for positioning mechanisms. The proposed model includes electromechanical relations which offer designers a broad range of possibilities for precise positioning and reliable model-based control. TULAs are experimentally investigated to determine the conditions that allow an optimal performance.