摘要
螺纹中径是衡量螺纹制造精度的重要参数,基于机器视觉测量螺纹时获取的是螺纹牙廓,而非具体螺纹中径值。为了提高机器视觉对螺纹中径的检测效率,提出了一种扩展虚拟三针法测量螺纹中径方法。该方法以机器视觉获取的螺纹轴截面图像为数据源,对获取的轴截面图像进行旋转矫正,通过计算出轴截面上各牙廓理想量针圆心坐标,利用几何关系并结合三针法原理得出中径值。以螺纹塞规M48×1.5-5g6h为对象,将扩展虚拟三针法测得的中径值与测长仪和螺纹综合测量仪测量结果进行比较。实验数据表明:该方法测得的中径标准差较测长仪降低了51.1%,与螺纹综合测量仪相当。在测量效率上高于测长仪1.3倍,是螺纹综合测量仪的1.4倍,为机器视觉测量螺纹中径提供了一种高效而可靠的测量手段。
The thread pitch diameter is an important parameter to measure the thread manufacturing accuracy.When measuring the thread based on machine vision,the thread profile is obtained,not the specific thread diameter value.In order to improve the efficiency of machine vision in detecting thread pitch diameter,an extended virtual three ball thread pitch diameter measurement method was proposed.This method took the threaded shaft section image obtained by machine vision as the data source,rotated and corrected the acquired axis section image,calculated the ideal needle center coordinates of each tooth profile on the shaft section,and used the geometric relation and the three ball method to obtain the center diameter value.Taking the thread plug gauge M48×1.5-5g6h as the object,the pitch diameter measured by the extended virtual three ball method was compared with that of the length measuring instrument and the thread comprehensive measuring instrument.The experimental data show that the standard deviation of the pitch diameter measured by this method is 51.1%lower than that of the length measuring instrument,which is equivalent to the comprehensive thread measuring instrument.The measuring efficiency is 1.3 times higher than that of the length measuring instrument and 1.4 times that of the comprehensive thread measuring instrument,which provides an efficient and reliable measuring method for machine vision to measure the thread pitch diameter.
作者
林葵
陈曼龙
余智超
邹滨阳
燕立志
景敏
LIN Kui;CHEN Manlong;YU Zhichao;ZOU Binyang;YAN Lizhi;JING Min(School of Mechanical Engineering,Shaanxi University of Technology;Shaanxi Key Laboratory of Industrial Automation)
出处
《仪表技术与传感器》
CSCD
北大核心
2024年第2期111-116,126,共7页
Instrument Technique and Sensor
基金
陕西省科技攻关计划(2022SF-469)。
关键词
扩展虚拟三针法
螺纹中径
机器视觉
旋转矫正
extended virtual three ball method
thread pitch diameter
machine vision
rotation correction
