Repulsive Force Electrostatic MEMS Actuation


Researchers at MMDL and Ryerson University have developed an electrostatic MEMS actuator utilizing repulsive forces. These actuators can also generate attractive forces enabling bi-directional out of plane motion. Rotational motions can be realized by hinging one side of the actuating unit.  The prototype micromirror have achieved optical rotation angles of up to +/-2.5° in both axes and a translation stroke distance of 86μm.

  • Eliminates pull-in voltage phenomenon
  • Eliminates stiction
  • Stroke is no longer limited by the initial gap distance
  • Simple design structure requiring only two layers
  • Commercial fabrication processes can be used



Figure-1. Repulsive Rotational Motion Actuator.


Figure-2. SEM image of a prototype of the repulsive force actuator.

Figure-3. Repulsive force electrostatic MEMS actuators.