基于组合型阈值分割的在线立铣刀侧刃磨损测量  

Online Side Edge Wear Measurement of Milling Based on Combined Threshold Segmentation

作　　者：田颖[1] 杨利明 Tian Ying;Yang Liming(School of Mechanical Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学机械工程学院,天津300072

出　　处：《天津大学学报（自然科学与工程技术版）》2023年第1期81-92,共12页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(51975407).

摘　　要：在实际生产中,现场测量立铣刀侧刃磨损是一项艰巨的工作.光照条件、刀具空间几何形状和初始位置的标定等因素对刀具磨损参数的测量精度影响很大.针对上述问题,提出了一种基于组合型阈值分割方法的在线立铣刀侧刃磨损测量方法,在保证测量精度的情况下最大限度地获取刀具磨损参数的有效信息.首先,提出一种图像剪切策略对捕捉到的磨损区域不同光强下的原始照片进行预处理,选取弱光下的刀尖区域和强光下的均匀磨损区域作为数据源;其次,对该数据源采用包含改进的直方图法和局部阈值分割法的组合型阈值分割法进行磨损区域提取;然后,将两种方法的结果进行叠加,去除磨损区域以外的多种噪声,并根据第1步的剪切位置,将分割后的刀尖区域图像与均匀磨损区域图像拼接,得到完整的磨损区域;最后,利用最小二乘法求出原始切削刃位置,标定磨损区域图像,计算刀具磨损参数.在立铣刀磨损实验中,测得侧刃的最大磨损量的精度大于98%,最大误差不超过5μm.实验结果表明,本文提出的方法能够获取全面的磨损区域信息,给出完整的磨损区域和精确的刀具磨损参数,有助于更加可靠地评估刀具磨损状态.In actual production,it is an arduous task to measure the side edge wear of milling on site.The measurement accuracy of tool wear parameters is greatly influenced by lighting conditions,tool space geometry,and initial position calibration.To solve the above mentioned problems,an online side edge wear measurement method of milling based on a combined threshold segmentation method was proposed to obtain the most effective information about tool wear parameters while ensuring measurement accuracy.An image-clipping strategy was proposed to preprocess the captured original photos of the worn area under different light intensities and select tooltip and uniform wear areas under low and strong light,respectively,as the data source.The data source used a combined threshold segmentation method that included improved histogram and local threshold segmentation methods to extract the wear area.Thereafter,the results of the two methods were superimposed to remove various noises outside the wear area.According to the cutting position of the first step,the segmented tooltip and uniform wear area images were spliced together to obtain the complete wear area.Finally,the original cutting edge position was calculated using the least square method,the wear area image was calibrated,and the tool wear parameters were calculated.In the milling wear experiment,the accuracy of measuring the maximum wear value of the side edge was greater than 98%,and the maximum error did not exceed 5μm.The experimental results showed that the proposed method in this paper could obtain comprehensive wear area information and provide a complete wear area and accurate tool wear parameters,allowing for a more reliable evaluation of tool wear status.

关 键 词：立铣刀侧刃磨损 组合型阈值分割 刀具磨损参数 

分 类 号：TG714[金属学及工艺—刀具与模具] TH69[机械工程—机械制造及自动化]