Design and performance evaluation of linear and rotary surface-driven electrostatic microactuators

A series of surface-driven rotary and linear electrostatic microactuators are designed and prototyped. A finite element method is used to aid in the actuator design and analysis of the electrostatic drive mechanism. The actuators, with the major components being a double-side copper coated 200 μm-thick glass epoxy stator board and a 34 μm-thick carbon-coated polyethylene-terephthalate (PET) film slider/rotor, are fabricated by using modified printed circuit board techniques. Experiments have shown that for the linear actuators, the maximum force density achieved is 106 N/m², at a driving voltage of ±80 V. For the rotary actuator, a maximum force density of 82 N/m² is achieved. The maximum load carrying capability of the actuators, defined as the ratio of the load carried by the slider/rotor to its eigen weight, is 170 for the linear and 190 for the rotary actuators, respectively. At a driving voltage of ±400 V, a maximum translational speed of 240 mm/s is observed for the linear actuator. For the rotary actuator, the maximum rotational speed obtained is 425 rpm