圆度测量中基于相关性分析的信号周期计算方法

A Method for Calculating Signal Period Based on Correlation Analysis in Roundness Measurement

论述了用单测头进行现场圆度测量时,应对圆周封闭性问题的解决方法。利用傅里叶变换分析测量信号的频域特性,得到信号的各频率分量,通过滤波的方式消除噪声影响、漂移影响。提出一种基于相关性分析的方法,准确获得测量信号周期。通过MATLAB进行仿真分析,验证了该方法的正确性和可靠性。通过改变测量信号的频率和幅值,即改变圆度测量时的转速和偏心量,得到周期计算误差随信号频率和幅值变化的关系。结果表明周期计算误差随频率的增大而减小,即频率越高,用该方法得到的周期越接近于信号的实际周期;但当频率一定时周期计算误差值不随幅值改变而产生显著变化。

A solution to circumferential closure is discussed when roundness is measured by a single probe for field.The frequency domain characteristics of the measured signal was analyzed by the Fourier transform to obtain the frequency components of the signal, and its effects of noise and drift on them were eliminated by filtering.A method based on correlation analysis was proposed to accurately obtain the measurement signal period, and the correctness and reliability of the method are verified by MATLAB simulation analysis.The periodic calculation error as the frequency and amplitude of the signal was obtained by changing the frequency and amplitude of the measured signal (i.e.the rotational speed and eccentricity of the roundness measurement) respectively.The results show that the period calculation error decreases with the increasing of frequency, that is, the higher the frequency is, the closer the period obtained by this method is to the actual period of the signal.However, when the frequency is a constant, the period calculation error value does not change significantly with the amplitude.