Study on Intelligence of Welding Robot with Visual Sensing System

去年，构建了一个基于视觉感知的焊缝识别基本系统。本文建立了一种用于薄板对焊焊缝识别和跟踪的鲁棒控制系统。该系统将CCD摄像机采集的图像数据应用到人工神经网络中进行焊缝的识别，检测焊缝的位置和形状。此外，为了不受坡口形状、坡口间隙等焊接条件变化的影响，获得良好的焊接效果，构建了焊接过程中焊接现象诊断和焊接条件控制系统。所得主要结果总结如下。(1)图像预处理：在将图像数据输入nn之前，使用二维空间滤波器对图像进行平滑处理，消除噪声。然后对其进行LOG滤波以增强焊缝图像的边缘，并进行二值化。将获得的图像数据作为N.N.的输入数据。(2)系统跟踪实验：对具有多种表面条件、材料类型、坡口形状、坡口类型、光照条件和电弧条件的贱金属焊缝进行了识别实验，验证了所构建识别系统的有效性。通过对低碳钢的对接焊接实验，验证了该系统在自动焊接中的有效性。(3)熔池监控：为了实现对焊接状态的实时控制，获得良好的焊缝，构建了弧焊熔池监控系统。由于熔池形状与焊缝熔透的关系密切，如果能控制熔池形状，就可以得到熔透最佳的焊缝。本研究将监测系统与电弧电流控制系统相结合，构建了基本的焊接控制系统。少

In last year, a basic system for recognizing welding line by visual sensing was constructed. In this year, a robust control system for recognizing and tracking the welding line in butt welding of thin steel plates was constructed. In this system, the recognition of the welding line was performed by applying the image data acquired by CCD camera to artificial neural network (N.N.) and position and shape of the welding line was detected. Furthermore, in order to obtain sound weld regardless change of welding conditions, such as groove shape, gap of groove and so on, system to diagnose the welding phenomena during welding and to control welding conditions were constructed.Main results obtained are summarized as follows.(1) Preprocessing of image : Before inputting image data into N.N., smoothing was applied to the image using 2-D space filter to eliminate noise. Then the LOG filter was applied to it in order to enhance the edge of the welding line image and the binarisation was applied. T … More he image data obtained were used as the input data to N.N..(2) Tracking experiments by the developed system : Experiments for recognizing welding lines of base metals which have several surface conditions, type of material, groove shape, type of groove, lighting conditions and arc conditions were performed, and the effectiveness of the recognizing system constructed was confirmed. Furthermore, butt welding experiments of mild steel plates were performed and effectiveness of the system to automatic welding was confirmed.(3) Monitoring of mlten pool : In order to realize real-time control of welding condition and obtain a sound weld, a monitoring system of molten pool in arc welding was constructed. As the relationship between the molten pool shape and penetration of weld has intimate relationship, if the shape of the molten pool can control, the sound weld with optimum penetration may be obtained. In this study a monitoring system and arc current control system were combined and a basic welding control system was constructed. Less