Advanced Materials and Nanotechnology Research Lab, Faculty of Mechanical Engineering, K.N.Toosi University of Technology, Tehran 19991-43344, Iran.
Sensors (Basel). 2011;11(11):10129-42. doi: 10.3390/s111110129. Epub 2011 Oct 25.
This paper describes an electrostatic excited microcantilever sensor operating in static mode that is more sensitive than traditional microcantilevers. The proposed sensor comprises a simple microcantilever with electrostatic excitation ability and an optical or piezoresistive detector. Initially the microcantilever is excited by electrostatic force to near pull-in voltage. The nonlinear behavior of the microcantilever in near pull-in voltage i.e., the inverse-square relation between displacement and electrostatic force provides a novel method for force amplification. In this situation, any external load applied to the sensor will be amplified by electrostatic force leading to more displacement. We prove that the proposed microcantilever sensor can be 2 to 100 orders more sensitive compared with traditional microcantilevers sensors of the same dimensions. The results for surface stress and the free-end point force load are discussed.
本文介绍了一种静电激励微悬臂梁传感器，其在静态模式下比传统微悬臂梁更灵敏。该传感器由具有静电激励能力的简单微悬臂梁和光学或压阻探测器组成。微悬臂梁最初通过静电力激励到接近拉入电压。微悬臂梁在接近拉入电压时的非线性行为，即位移与静电力之间的平方反比关系，为力放大提供了一种新方法。在这种情况下，施加到传感器上的任何外部负载都将通过静电力放大，从而导致更大的位移。我们证明，与相同尺寸的传统微悬臂梁传感器相比，所提出的微悬臂梁传感器的灵敏度可提高 2 到 100 个数量级。讨论了表面应力和自由端点力负载的结果。
