MEMS力平衡加速度传感器以测量误差最小为目标的控制算法  

CONTROL ALGORITHM OF A MEMS FORCE-BALANCE ACCELEROMETER FOR MINIMIZING THE MEASUREMENT ERROR

作　　者：刘志强 夏磊 张猛 黄志龙[1] 宦荣华[1] Liu Zhiqiang;Xia Lei;Zhang Meng;Huang Zhilong;Huan Ronghua(Department of Mechanics,Key Laboratory of Soft Machines and Smart,Zhejiang University,Hangzhou 310000,China)

机构地区：[1]浙江大学航空航天学院应用力学研究所,浙江省软体机器人与智能器件研究重点实验室,杭州310000

出　　处：《动力学与控制学报》2022年第6期94-100,共7页Journal of Dynamics and Control

基　　金：国家自然科学基金资助项目(12172323);浙江省自然科学基金重点资助项目(LZ22A020003)。

摘　　要：力平衡传感器(FBA)测量加速度是由反馈控制力与外界惯性力平衡时的控制力计算得到的,力平衡控制算法是力平衡传感器的核心.传统控制算法多以敏感元件偏移平衡位置最小为目标,限制了力平衡加速度计的测量精度和适用带宽.本文以MEMS力平衡传感器为对象,提出了一种以测量误差最小为目标的力平衡加速度计最优控制算法.引入测量误差新变量,将难以处理的力平衡控制转化为以响应最小为目标的经典控制问题,在此基础上获得了最优控制力的解析表达式,实现了对未知加速度信号的实时高精度检测.分别针对三种不同类型的输入加速度信号(阶跃、周期和随机)进行检测仿真,发现提出的算法能够准确地检测各类输入加速度信号,测量信号频带达kHz量级,同时在该控制算法下敏感元件的振动响应也得到有效控制,保证了加速度传感器的大动态范围.研究成果可为高精度和宽频带力平衡加速度传感器的研究提供基础.The measurement acceleration of the force-balance accelerometer(FBA)is calculated by the control force when the feedback control force is balanced with the external inertia force.Thus,the force-balance control algorithm is the core of a force-balance sensor.Most of the traditional control algorithms aim at minimizing the offset position of the sensitive elements from the equilibrium,which limits the measurement accuracy and applicable bandwidth of the force-balance accelerometer.In this paper,taking a MEMS force-balance sensor as the object,an optimal control algorithm of force-balance accelerometer is proposed for minimizing the measurement error.By introducing measurement error as a new state variable,the difficult force-balance control is transformed into an optimal control problem for response minimization,from which the analytical expression of the optimal control force is obtained.Based on the proposed control strategy,the real-time high-precision detection of unknown acceleration signal is realized.Numerical simulations are carried out for three different types of input acceleration signals(step,periodic and random).It is found that the proposed algorithm can accurately detect all kinds of input acceleration signals,and the frequency band of the measured signal reaches up to kHz.At the same time,the vibration response of the sensitive element can be effectively controlled,which guarantees the large dynamic range of a FBA.Our work provides the basis for the research of high performance force-balance accelerometer with high-precision and wide frequency band.

关 键 词：MEMS 最优控制 振动 力平衡传感器 

分 类 号：O39[理学—工程力学]