基于最小二乘法的振动监测系统测量噪声现场标定  

On-site Calibration of Measurement Noise in Vibration-based Structural Health Monitoring System Based on Least Square Method

作　　者：李宾宾 朱伟 谢炎龙 朱作 LI Binbin;ZHU Wei;XIE Yanlong;ZHU Zuo(ZJU-UIUC Institute,Zhejiang University,Haining 314400,Zhejiang,China;College of Architectural Engineering,Zhejiang University,Hangzhou 310058,China;College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,Guangdong,China;School of Civil and Environmental Engineering,Nanyang Technological University,Singapore 639798,Singapore)

机构地区：[1]浙江大学浙江大学伊利诺伊大学厄巴纳香槟校区联合学院,浙江海宁314400 [2]浙江大学建筑工程学院,杭州310058 [3]深圳大学土木与交通工程学院,广东深圳518060 [4]南洋理工大学土木与环境工程学院,新加坡639798

出　　处：《噪声与振动控制》2024年第4期110-117,共8页Noise and Vibration Control

基　　金：国家自然科学基金资助项目(青年项目)(51908494);国家重点研发计划资助项目(2019YFB2102702);深圳市科技计划资助项目(JCYJ20220818095608018,JSGG20210802093207022)。

摘　　要：分析振动监测系统的测量噪声水平是结构健康监测设计的重要步骤,有利于优化测试方案和后期模态参数识别。本文从数据采集全过程入手分析测量噪声的主要来源和统计特性,基于最小二乘法原理,提出标定硬件噪声水平的“n信道”方法和估计多信道同步误差的方法。前者允许以任意数量的信道组合进行噪声估计,能够充分利用所有信道的信息,增强结果的稳定性;后者运用时滞测量信号的频域特性,通过互功率谱密度的比值实现信道间亚毫秒级同步误差估计。所提方法的正确性、鲁棒性和实用性通过某桥梁振动监测系统的测量数据得到验证。Calibrating the noise level is an essential step in the design of vibration-based structural health monitoring(SHM)system.It is beneficial to the optimization of the test configuration and the later modal parameter identification.Based on the investigation of the overall data acquisition process,the main source and the stochastic characteristics of the measurement noise are analyzed.Based on the least squares method,an n-channel method is developed for the channel hardware noise quantification and a strategy is proposed to quantify the synchronization error.The former allows one to estimate the noise with an arbitrary number of sensors,utilize the information from all channels and thus yield more robust estimation;the latter allows one to realize the estimation of synchronization error of sub-milliseconds by using the ratio of the cross-power spectrum density based on the frequency-domain representation of signals with time lag.The correctness,robustness,and feasibility of the proposed methods are verified in a practical SHM project.

关 键 词：振动与波 结构健康监测 拾振器 测量噪声 同步误差 最小二乘法 

分 类 号：O329[理学—一般力学与力学基础]