三点接触疲劳试验机的测试信号相干函数分析  

Coherent Function Analysis on Testing Signals of Fatigue Life Tester with Three Points Contact

作　　者：周井玲[1] 李玉静[1] 左伟明[1] 

机构地区：[1]南通大学机械工程学院,江苏南通226019

出　　处：《自动化仪表》2013年第7期9-11,共3页Process Automation Instrumentation

基　　金：国家自然科学基金资助项目(编号:60974049);国家十一五重点基金资助项目(编号:JPPT-115-197);江苏省自然科学基金资助项目(编号:BK2009613)

摘　　要：为了提高三点接触疲劳试验机的动力学性能,采用Matlab软件对试验机系统信号进行分析。首先由自相关分析可以得出,输入和输出信号是由多个周期成分叠加而成的周期信号;然后对输入和输出做互相关分析,得到了消除噪声后的真实输出信号;最后进行相干函数分析,得出在各零部件激振频率下的相干函数值约为0.9。试验结果表明,试验机系统为线性系统。该研究结果为模态分析和动力学分析提供了理论依据。In order to enhance the dynamics performance of the fatigue life tester with three points contact, the signals of the tester system are analyzed by adopting Matlab software. With auto correlation analysis, it is found first that the input and output signals are both periodic signals, and superimposed by multiple cycles ingredients. Then, cross correlation analysis is conducted to obtain real output signals after noise elimination. Finally, coherent function analysis is implemented ; the 0.9 of coherent function value under vibration energizing frequency of each component is obtained. The result indicates that the tester system is linear system. The research result provides theoretical basis for modal analysis and dynamics analysis.

关 键 词：MATLAB 自相关 相干函数 快速傅里叶变换 线性系统 

分 类 号：TN911.6[电子电信—通信与信息系统]