考虑应力分布约束的压电全向加速度计梁结构优化设计  

Optimization of supporting beams of piezoelectric omnidirectional accelerometer under stress constraint

作　　者：王岩[1] 赵剑[1] 夏阳[1] 刘蓬勃[1] WANG Yan;ZHAO Jian;XIA Yang;LIU Peng-bo(School of Automotive Engineering, Dalian University of Technology, Dalian 116081, China)

机构地区：[1]大连理工大学,工业装备分析国家重点实验室汽车工程学院,辽宁大连116081

出　　处：《光学精密工程》2020年第8期1751-1760,共10页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.U1930206);国家自然科学基金资助项目(No.61874019);国家重点研发计划资助项目(No.2018YFA0703200)。

摘　　要：针对全向加速度计柔性支撑结构应力集中问题,以压电加速度计高灵敏度为目标,建立了考虑应力分布状态的新型全向加速度计柔性支撑结构优化设计模型。借助遗传算法,通过协同优化初始长度15 mm压电曲梁不同部位的曲率和直径,得到了具有变截面特征的压电全向加速度计曲梁支撑结构。数值实验结果表明,所得到的3压电曲梁支撑加速度计解算的全向灵敏度为传统3直梁支撑加速度计的2.5倍,且结构的最大应力仅为传统直梁结构的70%~90%。由于应力降低,曲梁加速度计的加速度线性测量范围扩大为传统直梁加速度计的1.2倍。在1~81 Hz加速度下,曲梁加速度计解算的全向灵敏度为0.7~1.3 V/g,为直梁加速度计的1.6~2.9倍。该设计解决了通过直接改变梁结构形式难以实现传统梁结构加速度计高灵敏低应力响应的问题。To solve the problem regardingthe stress concentration offlexible supporting structures of omnidirectional accelerometers,an optimization model was established herein,considering the constraint of the stress distribution.By means of optimizing the curvatures and diameters of different parts of a piezoelectric curved beam,a novel axially polarized optimized omnidirectional accelerometer with a curved beam of variable crosssection was obtained using the genetic algorithm.The numerical results show that the omnidirectional sensitivity of the optimized curved-beam accelerometer is 2.5 times that of the initial straight-beam accelerometer,and its maximum stress is 0.7-0.9 times that of the initial straight-beam accelerometer.Therefore,the linear measurement range of the curved-beam accelerometer is 1.2 times that of the initial straight-beam accelerometer.The omnidirectional sensitivity of the curved-beam accelerometer is 0.7-1.3 V/g under acceleration in the range of 1-81 Hz.Overall,the design method forthe curved-beam accelerometer can overcome the difficultiespresented regardingoptimization of the sensitivity and stress distribution simultaneously.

关 键 词：灵敏度 应力 压电 曲梁 全向加速度计 

分 类 号：TH8[机械工程—仪器科学与技术]