基于数学形态学的螺纹轮廓曲线滤波方法

Thread Contour Curve Filtering Method Based on Mathematical Morphology

接触式螺纹测量系统采集到的表面原始螺纹轮廓信号中往往伴随着随机噪声,这对后续计算螺纹参数值的影响非常大,所以找到一种既能有效滤除噪声同时保护螺纹轮廓边缘而且在选取滤波参数上也比较方便的方法十分重要,本文将数学形态学运用到螺纹轮廓信号的滤波中,确定合适的结构元素及长度,以得到该方法的最优滤波效果。然后对螺纹仿真信号进行试验,以均方根误差和信噪比作为滤波效果的评价指标。最后用实测螺纹轮廓信号进行检验,结果表明,形态学滤波方法能有效逼近期望螺纹轮廓信号,同时滤波参数的选取简单适应范围广。

The original thread profile signal of the surface collected by the contact thread measurement system is often accompanied by random noise,which has a great influence on the subsequent calculation of the thread parameter value.It is also very important that the filtering parameters are more convenient.In this paper,mathematical morphology is applied to the filtering of thread profile signals to determine the appropriate structural elements and lengths to obtain the optimal filtering effect of the method.Then the thread simulation signal is tested,and the root-mean-square error and signal-to-noise ratio are used as the evaluation indexes of the filtering effect.Finally,the actual measured thread contour signal is used for testing.The results show that the morphological filtering method can effectively approximate the expected thread contour signal,and the selection of filtering parameters is simple and has a wide range of adaptation.