Piezoelectric Inertia MotorsA Critical Review of History, Concepts, Design, Applications, and Perspectives

Piezoelectric inertia motorsalso known as stick-slip motors or (smooth) impact drivesuse the inertia of a body to drive it in small steps by means of an uninterrupted friction contact. In addition to the typical advantages of piezoelectric motors, they are especially suited for miniaturisation due to their simple structure and inherent fine-positioning capability. Originally developed for positioning in microscopy in the 1980s, they have nowadays also found application in mass-produced consumer goods. Recent research results are likely to enable more applications of piezoelectric inertia motors in the future. This contribution gives a critical overview of their historical development, functional principles, and related terminology. The most relevant aspects regarding their designi.e., friction contact, solid state actuator, and electrical excitationare discussed, including aspects of control and simulation. The article closes with an outlook on possible future developments and research perspectives.