Piezoelectric Actuators and Motors: Materials, Designs, and Applications

Piezoelectric actuators are unique driving force‐generation devices, which can transfer input electric energy into force, displacement, or movement outputs efficiently and precisely via piezoelectric effect‐based electromechanical coupling instead of electromagnetic induction. In comparison with traditional electromagnetic actuators, the most important features of the piezoelectric actuators are their compact size, flexible design, and ability to provide nanometer or sub‐micrometer positioning. Here, recent progress in nonresonance piezoelectric actuators including multilayer ceramic actuators, step motors, inertial motors, and resonance ultrasonic motors, such as linear motors, rotary motors, multidegree of freedom motors, and microelectromechanical system actuators, is comprehensively presented. The working principles and properties of these actuators are explained, and the piezoelectric materials and configurations, fabrication, and applications are provided. Furthermore, from the aspects of materials, designs and applications, challenges and outlooks for future developments of piezoelectric actuators and motors are also discussed. Piezoelectric actuators are a type of device that can transfer electric energy into mechanical energy output via piezoelectric effect and they play an irreplaceable role in precision actuations. Herein, recent progress in nonresonance piezoelectric actuators, resonance ultrasonic motors, and microelectromechanical system actuators is comprehensively introduced. From the aspects of materials, designs and applications, challenges and outlooks are also discussed.