歪度指标是描述信号概率密度函数的重要参数。在对非平稳信号进行时域分析时，利用歪度指标反映了振动信号的非对称性，用来判断轴承是否发生碰磨。本文件中将歪度指标独立制作了子VI，便于labview程序调用。(The skewness index is an important parameter to describe the probability density function of a signal. When the non-stationary signals are analyzed in time domain, the skewness index is used to reflect the asymmetry of the vibration signals, which is used to judge whether the bearings have been touched or not. This document will be independent of the index made a sub VI, easy for LabVIEW program calls.)