微机械电容式加速度计的结构设计分析

微机械电容式加速度计的基本参数如固有频率、非线性度、分辨率等首先取决于其本身的结构，因此加速度计结构的设计选取至关重要。本文首先综合比较了微机械电容式加速度计的三种常见结构三明治摆式、翘翘板摆式和梳齿式的各自特点，指出了定齿偏置结构的梳齿式微机械加速度计的优点。并以该结构为分析对象，从加速度计的分辨率、量程、稳定性、灵敏度等性能分析比较了多种结构梁，提出了折叠梁的综合性能最好，最后通过分析计算出了折叠梁在检测方向的刚度。

Structure Design & Analysis On Variable-Capacitance Micromechanical Accelerometer

Many basic parameters of variable-capacitance micromechanical accelerometer such as frequency,nonlinear ,resolution, are decided by its structure firstly. So it is very important how to design and select the structure of micromechanical accelerometer. Firstly, the relevant features of three kinds of structure such as CMSA, PMSA, FMSA are summarized and compared ,and the advantages of finger-shaped variable-capacitance micromechanical accelerometer on the base of bias stationary structure are presented. Then the bias structure is taken as an example, the resolution, full scale, stability, precision of many kinds of structure beams are analyzed and compared, the conclusion is given that the best structure is folded beams structure. Finally the rigidity formula of the folded beam on the measured direction are analyzed and given.