微机电系统应用中的非线性力学问题分析

Nonlinear analysis of mechanical problems in MEMS application

微机电系统(MEMS)中常作为和力有关的传感器使用的悬臂梁类型结构,在使用过程中经常会出现小变形、大位移的情况,这时传统的线性分析方法会导致较大的系统误差。本文基于二次梁理论给出了该几何非线性问题的理论解,其正确性通过有限元的数值计算结果得到验证。这个通过非线性分析得到的理论解不但校正了线性分析方法的系统误差,提高了系统精度,而且扩大了系统的有效使用范围。

Usually as force sensor, micro-cantilevers are widely used in MEMS, the deformation is small and the displacement is big. In this case, large systematic error will be resulted when the traditional linear theory is used. In this paper, the geometric nonlinearity problem is analyzed based on the second beam theory, and a theoretical solution is proposed, whose accuracy is verified by FEM numerical simulation. The solution not only corrects the errors introduced by linear method, but also extends the range of detectable load by the MEMS device.