结合阈值法和模极大值法的冲击加速度信号降噪  

Shock Acceleration Signal Noise Reduction Combined with Threshold Method and Modulus Maximum Method

作　　者：卿涛 丁问司[1] QING Tao;DING Wen-si(School of Mechanical&Automotive Engineering,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学机械与汽车工程学院,广东广州510640

出　　处：《机械工程与自动化》2021年第3期1-3,共3页Mechanical Engineering & Automation

基　　金：国家自然科学基金资助项目(11272122);广东省科技计划项目(2017B010136113)。

摘　　要：微机电加速度传感器对交变冲击机构的实测信号中包含噪声干扰,影响加速度积分的精度,因此需要进行降噪处理。针对小波模极大值方法存在模极大值点搜索量大以及小波系数重构过程鲁棒性低的问题,提出了利用阈值法来改善模极大值点的搜索过程,并利用分段埃尔米特插值算法重构小波系数。仿真实验表明:改进后的方法能够保留较多的有用信号,并提高了模极大值点的搜索效率及算法的鲁棒性。将改进后的方法应用于交变液压冲击器实验中,对所采集的冲击加速度信号进行分析,验证了其在实测交变冲击加速度信号处理中的可行性。The measured signal of the MEMS acceleration sensor to the alternating impact mechanism contains noise disturbance,which affect the accuracy of acceleration integration,so noise reduction processing is required.In view of the large search volume of the modulus maximum point of the wavelet modulus maximum method and the low robustness of the wavelet coefficient reconstruction process,and it is proposed to use the threshold method to improve the search process of modulus maximum points,and to reconstruct the wavelet coefficients using the piecewise Hermitian interpolation algorithm.Simulation experiments show that the improved method can retain more useful signals,and improve the search efficiency of modulus maximum points and the robustness of the algorithm.By applying the improved method to the alternating hydraulic impactor experiment and analyzing the collected shock acceleration signal,it is verified that it is feasible in the actual measurement of alternating shock acceleration signal processing.

关 键 词：交变冲击机构 加速度信号处理 模极大值法 阈值法 信号降噪 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]