TABLE OF CONTENTS This chapter has listed, in a quite exhaustive way, the different types of electrostatic actuators that have been realized so far, thanks to microsystems technology.
Having determined the electrostatic force characteristic by analytical calculation, the micro-actuator have been sorted according to their topology or to the type of motion they are able to experiment: parallel plates capacitive actuator, comb-drive structure, torsion mode actuator and rotating micro-motor. In the last part has been presented more specific designs that synthesize more complex motion.
As the implementation of electrostatic actuation is very simple, its utilization relies on fabrication technologies able to produce functional devices. When micro-machining technology proposes multiple mobile structural layers, more and more complex mechanisms can be realized to cover specific applications. This is illustrated by the last example in Figure 37, realized with five layers of polysilicon (one electrical level and four mechanical ones) [SAN 01]. This figure shows a linear translator with a stepwise motion produced by combined comb-drive actuators. This system integrates a speed reducer to obtain forces intense enough to fold 3D structures.
Despite the huge number of electrostatic actuators that have been demonstrated in laboratories, few of them have been introduced in industrial products. Most of...
