基于视觉传感系统的中厚板焊接机器人研究

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	基于视觉传感系统的中厚板焊接机器人研究
	KIDDEE PRASARN1,2
	2017-04
学位类型	工学博士
中文摘要	机器人在焊接行业己经使用了几十年。然而，大多数的焊接机器人仅仅应用于简单的焊缝类型，如薄板的对接焊缝。在中厚板的焊接过程中，焊缝几何形状比较复杂，焊缝检测和焊缝跟踪难以得到实现。本文主要研究基于视觉传感系统的中厚板焊接机器人，主要包括三个部分，1)视觉传感系统标定；2) 焊缝特征检测；3)基于视觉传感系统的运动控制。本文主要研究内容如下：首先，提出了一种交叉线激光的标定技术。该方法的特点如下：1)只需要一个普通的棋盘格，2)只需要两幅图像，3)可以实现交叉线结构光的两个激光平面同时标定。标定结果具有较高的精度，可以应用于实际的生产制造，以提高焊接质童。其次，提出了一种实时特征检测方法。使用十宇线结构光的交叉标记来精确确定感兴趣E域。在所提出的方法中，模板可以n动创逑，并且沿着激光条纹边缘进行匹配。实验结果表明，该方法较高的精度和较少的计算量，可以满足实时检测系统。第三，提出了基于分层策略和改进卡尔蛙滤波的特征检测方法，提高实时特征检测的稳定性。首先，用R.ANSAC算法粗略估计交叉结构光的十字标记，然后，利用均值漂移算法精确修正十字标记的位罝。M后，使用马氏距离分类器更新沅童卡尔蛙滤波器的状态。实验结果表明，该方法可以用于不同中厚板的焊缝特征检测。第四，采用概率技术同时实现中厚板焊缝跟踪和移动焊接机器人定位。应用扩展卡尔蛙滤波器进行焊缝跟踪控制，应用粒子滤波器进行机器人定位。实验结果表明，本文所设计的机器人焊缝跟踪系统具有较高的准确性和稳定性。最后，对本文的研宂内容和未来需要开展的工作进行总结和探讨。
英文摘要	Robots have been employed in the welding industry for many decades. However, most of the welding robots are used for weld seams with simple shape such as butt seams in thin plates. In thick plate welding, it is not easy to detect and track the weld seam because of its complex geometry. This study focuses on the development of thick plate welding robot using visual sensing system. The study consists of three main parts, namely 1)visual sensing system calibration, 2)weld seam features detection, and 3)motion control based on visual sensing system. The core contents of the research are as follows. Firstly, we propose a particular calibration technique which is accurate, practical, quick, and simple to calibrate a cross-line structured light. The highlights of the method are 1)only a regular chessboard is used, 2)only two additional images are needed, 3)the two planes of the cross-line structured light can be calibrated concurrently. The accuracy of calibration is enough for the weld seam tracking system. The results of this study are expected to be applied in real manufacturing to improve the welding quality. Secondly, a real-time feature detection method is proposed. We use the cross mark of the cross-line structured light as the pinpoint for designating the region of interest(ROI). In the proposed method, templates can be created automatically, and they are manipulated to match the edge-like locations. As a result of the implementation, high accuracy and precision of detection are obtained. Furthermore, the method can reduce a huge computation cost, and thus it is adequate for a real-time detection system. Thirdly, a real-time and robust feature detection method using hierarchical strategy and modied Kalman lter is proposed to stabilize the real-time features detection. In the rst step, the cross mark of the cross-line structured light is coarsely estimated by RANSAC algorithm, and then the location of the cross mark is rened by mean shift algorithm. In the second step, the scalar Kalman lter is applied to the detection to improve the robustness. In the last step, vi A Study on Thick Plate Welding Robots Using Visual Sensing System we use Mahalanobis distance classier to update the state of the scalar Kalman lter. As a result of the implementation, the detection is achieved even though the feature is translated to the dierent surface. Moreover, the low computational cost in the proposed method meets requirements of real-time feature detection. Thus, it satises the requirement of the real-time weld seam tracking system. Fourthly, probabilistic techniques are used to track the thick plate weld seam and localize the welding mobile concurrently. In particular, the extended Kalman lter is employed in the weld seam tracking control; and the particle lter is applied to the robot localization. As a result of the implementation, a well-integrated control system is demonstrated. The accuracy and stability of the proposed system are reliable. Moreover, the extended work of the study is considered to be a promising one. Finally, all aspects of this study are summarized and discussed. Also, the future work of the research is suggested.
关键词	中厚板焊缝十宇线结构光视觉传感器标定焊缝特征检测焊缝跟踪控制
文献类型	学位论文
条目标识符	http://ir.ia.ac.cn/handle/173211/15510
专题	毕业生_博士学位论文
作者单位	1.中国科学院大学 2.中国科学院自动化研究所
第一作者单位	中国科学院自动化研究所
推荐引用方式 GB/T 7714	KIDDEE PRASARN. 基于视觉传感系统的中厚板焊接机器人研究[D]. 中国科学院大学. 中国科学院大学,2017.

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基于视觉传感系统的中厚板焊接机器人研究（12176KB）	学位论文		限制开放	CC BY-NC-SA