Open Loop Vibrational Control for Cantilevered Electromagnetic Actuators

Electromagnetic cantilevered actuators are simple for fabrication and operation, while its mobility region is strictly limited due to pull-in instability. To extend the mobility region, we have proposed a novel open loop oscillatory control method which does not need additional sensors. In this paper, a sufficient condition for electromagnetically driven cantilevered actuators that cause pull-in instability is introduced, and the synthesis and robustness of the the open loop oscillatory control for the electromagnetically driven cantilevered actuators are discussed. Then we show that the oscillatory controlled system can prevent pull-in instability without feedback at the cost of the applied current. Their effectiveness are shown through numerical simulations and proof experiments for our prototype electromagnetic actuator