Microactuators

Microactuators are emerging as important tools that are capable of performing the tasks of conventional tools in the macroworld, but they are much smaller and allow greater precision. A review of electrostatic, piezoelectric, and electrothermal microactuators is presented. The basics of these three actuation principles and characteristics are briefly explained to highlight the motivation behind the selection of different microactuators. Various design models of electrostatic, piezoelectric, and electrothermal microactuators are described and compared from the perspective of the mechanism and output performance. Limitations of existing designs are identified to improve some of these microactuators to gain better performance or reliability. Finally, key challenges in different microfabrication techniques associated with their process and compatibility with commercial foundries are highlighted, as this aspect decides the viability of microactuators commercially and economically