【作者】 王珂娜；

【导师】 邹北骥；

【作者基本信息】 湖南大学 ， 计算机应用技术， 2005， 硕士

【摘要】 运用计算机视觉技术进行焊缝识别是焊接机器人研究的重要内容之一。本文以智能焊接机械手的设计为目标，在研究计算机视觉技术和神经网络技术的基础上，提出了运用基于神经网络的计算机视觉技术进行焊缝识别的新方法，并将其应用于智能焊接机械手的设计与开发中，取得了良好的结果。 本文首先对焊接机器人传统的示教方式进行了研究。传统的示教方式工作量大，效率低，无法实现智能化焊接，而运用基于神经网络的计算机视觉技术的焊缝自动识别方法不需要外加的辅助设备即可实现焊缝的自动识别。本文详细阐述了该方法的原理及实施方案，并对图像的畸变校正方法进行了深入的研究。发现常用的校正方法需要建立畸变数学模型，模型的求解参数复杂、计算量大且存在数值计算误差。针对上述问题，本文提出了运用神经网络进行图像畸变校正的新方法。用这种方法对模架图像进行畸变校正，获得了良好的实验结果。随后运用图像对比度增强技术、图像分割技术及神经网络边缘检测技术对模架图像进行了预处理。针对Hough变换提取直线算法不能检测直线端点、容易重复检测直线以及提取直线精度不高的缺陷，对Hough变换算法进行了改进。最后运用改进的Hough变换算法提取了模架筋板边缘线，识别了焊缝平面坐标。 本文在理论研究、分析和大量实验的基础上，参与开发智能焊接机械手，共同完成了整个系统的机械、电气控制部分的设计、安装和调试，运用Visual C++6.0编程，开发了焊接机械手的控制系统软件。更多还原

【Abstract】 Auto-recognizing the welding joint based on computer vision is an important aspect in the research field of the welding robot. The conventional teach mode for the welding robot is of many disadvantages such as the great workload and low efficiency. After we have explored some existed methods, we put forward a new approach of auto-recognizing the welding joint in this paper, which bases on computer vision and neural networks.In this paper we introduce the principle and implement scheme from our method firstly. Then, some correction methods for the distorted image are presented, in which the distortion model needs to be set up and have a complex solving process including complicated calculation and numeral error. So we give a new correction method based on neural networks in this paper, which has been better applied to distort the die carrier images. Many good experimental results from our method have also been obtained. And then, we preprocess the die carrier images with the techniques of intensifying contrast, image segmentation and edge detection based on neural networks. We have also improved the Hough transforms algorithm for the two ends of the line cannot be detected and the lines are detected repeatedly with a low precision by using the conventional Hough transforms. Finally, the improved Hough transforms algorithm is utilized to extract lines from the die carrier images.On the base of the theory analysis and research, the whole mechanical system and electrical system for welding robot have been established and the control software is developed with VC6.0.更多还原