针对传统长度测量方法无法检测节距的问题,提出一种基于机器视觉的光缆节距检测方法。该方法通过激光测速仪检测生产线速度,产生相应脉冲触发工业相机采集信息,低角度与背光照明相结合搭建检测系统。利用预处理操作解决灰度重叠几何性质不稳定等问题。为了提高定位精度,提出自动构造模板法有效快速自动构造匹配模板,并运用模板分区精确定位法解决直接匹配误判问题,进而匹配识别换向点并检测节距长度。通过理论分析和实验验证,该方法测出节距结果与标准节距结果误差为0.02~0.10 mm,满足工程需要,且系统运行稳定可靠,为检测光缆节距提供了一种新途径。

Traditional length-measurement methods cannot detect pitch. Accordingly, in this work, an optical cable pitch detection method based on machine vision is proposed. This method uses a laser velocimeter for detecting the speed of a production line and generates corresponding pulses to trigger the acquisition information by an industrial camera. A detection system was built by combining low angle with backlight illumination. Furthermore, a preprocessing operation was used to solve the instability of overlapping geometric properties of gray levels. To improve the positioning accuracy, an automatic template construction method is proposed to effectively construct matching templates. A template partition precise-positioning method was used to solve the problem of direct matching misjudgment; then the commutation point was matched and identified and the pitch length was detected. Theoretical analysis and experimental verification reveal that the error between the measured and standard pitch results is within 0.02-0.10 mm, which meets engineering requirements, and the system runs steadily and reliably. The proposed method provides a new way to detect optical cable pitch.