A microactuator is a microscopic servomechanism that supplies and transmits a measured amount of energy for the operation of another mechanism or system. As a general actuator, following standards have to be met:

For microactuator, there are two in addition

The basic principle can be described as the expression for mechanical work
${\displaystyle W={\overrightarrow {F}}\cdot \Delta {\overrightarrow {r}}}$
since an actuator is to manipulate positions and therefore force is needed. For different kind of microactuators, different physical principles are applied.