Tuning the quality factor of microcantilever using hydrodynamic coupling of micro structures

Abstract

This study demonstrates the concept of controlling the quality factor of a micro-cantilever using hydrodynamic coupling of active mechanical structures. The active micro structures (auxiliary-cantilevers) adjacent to the micro-cantilever (operating-cantilever) are exploited to generate hydrodynamic force to change the air damping of the operating-cantilever. Thus, the quality factor of operating-cantilever can be increased or decreased by changing the phase of the excitation force on the auxiliary-cantilevers. In addition, the tuning range of quality factor can be controlled by varying the magnitude of the excitation force on the auxiliary-cantilevers or the adjacent distance between micro-cantilevers. In application, magnetic actuated micro-cantilever arrays were fabricated and characterized. Measurements demonstrate that the variation of quality factor is from -39% to +28% using the proposed approach.

Vibration of sensor diaphragm with residual stress coupled with liquids: effect of the residual stress

“…The use of micro-cantilevers as transducers in biochemical sensing systems has increased in recent years. Many research efforts in this field have been reported (Ramos et al, 2006;Mahmoodi and Jalili, 2007;Mahmoodi et al, 2008;Lee et al, 2009). Several works have modeled the vibrational dynamics of cantilever-type devices operated in air (Yum et al, 2004), liquid (Zhang and Turner, 2007;Chon et al, 2000), and vacuum (Burns et al, 1996).…”

Self-sensing and quality factor control circuits for piezoelectric millimeter-sized resonant cantilevers

“…Apart from the advantages of enhancing the quality factor, tuning the quality factor to a prespecified value would also increase the dynamic performance of resonant cantilever sensors (Lee et al, 2009). For determining liquid densities by PEMC, for example, the resonant frequency of the cantilever would change principally because of the liquid density variations (displaced mass effect).…”