Embedded machine vision online measure-control system of defocusing amount in laser cladding forming

被引:0
作者
Wang, Tao [1 ]
Fu, Geyan [1 ]
Shi, Shihong [1 ]
机构
[1] School of Mechanical and Electrical Engineering, Soochow University, Suzhou, 215000, Jiangsu
来源
Zhongguo Jiguang/Chinese Journal of Lasers | 2015年 / 42卷 / 03期
关键词
Embedded system; Laser cladding forming; Laser technique; Machine vision; Molten pool;
D O I
10.3788/CJL201542.0303011
中图分类号
学科分类号
摘要
To maintain the defocusing amount during the metal laser cladding forming experiments, the distance between the forming surface and the nozzle should be fixed. Based on optical triangle method, an embedded machine vision online measuring system for controlling the laser defocusing amount is proposed. The formula for designing the lens focal length of the measuring camera is deducted, and both hardware and software solutions are meanwhile presented. To process the gained pictures from the measuring camera effectively and stably, a new algorithm estimation based on molten pool gray threshold is used for programming. The output voltage from the measuring system is also integrated into the robot controlling coding which helps adjust the nozzle position automatically once the laser defocusing amount is offset. This measuring system is later verified through several metal laser cladding forming experiments to be stable and precise. By comparing the thin-wall cylinder forming parts, the surface roughness of the part made with the measuring system is much brighter and cleaner than the ones without this system. ©, 2015, Science Press. All right reserved.
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页数:8
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