Coupled vibration of microcantilever array induced by airflow force

The coupled vibrations of microcantilevers induced by airflow were analyzed to facilitate the development of high-speed information and sensing devices that use microactuator arrays. Simple formulas, from which the vibrational coupling amplitude and damping ratio can be obtained, are derived by replacing the cantilevers with strings of spheres, solving Stokes equation, and combining this with an ordinary beam equation. The coupling amplitude was found to increase as the beam size, beam gap, internal friction, and the difference in the resonant frequencies of the beams decreased and the damping ratio increased as the beam size was reduced. The validity of the theory is verified with actual-size and enlarged model experiments.