正交异性钢桥面板疲劳裂纹图像巡检测量系统研究

Research on Fatigue Crack Image Routing Inspection and Measurement System for Orthotropic Steel Bridge Decks

为提高正交异性钢桥面板疲劳裂纹检测效率及精度,研究提出了一套集磁吸附攀爬机器人与裂纹图像处理平台为一体的新型巡检测量系统。攀爬机器人所搭载的磁吸附装置使其能安全吸附在顶板、U肋侧板以及横隔板表面,并按预先设定路线或手动操作路线开展裂纹图像巡检工作,裂纹采集平台通过Wi-Fi远程控制工业相机与激光测距自标定装置,采集并实时回传图片及标定数据以计算相机的内参和外参。后处理阶段,裂纹处理平台基于神经网络训练和单应性矩阵计算,完成裂纹图像识别以及裂纹几何特征提取,并借助图像拼接技术生成钢桥面板疲劳裂纹分布全景图。在正交异性钢桥面板足尺模型上应用该系统进行裂纹图像采集与测量,结果表明:各区域常见疲劳裂纹均可实现无障碍测量,标尺长度的测量误差均在0.2%以内,平均误差仅为0.14%,裂纹分辨能力达到亚毫米级。研发的疲劳裂纹图像巡检测量系统具备很高的测量精度,且与传统方法相比具有检测过程自动高效、检测区域全覆盖等显著优势,可在实际桥梁工程中推广应用。

In order to enhance the inspection efficiency and accuracy of fatigue cracks in orthotropic steel bridge decks,a set of innovative routing inspection and measurement system combining magnetic absorbing climbing robot and crack image processing platform is developed.The magnetic absorbing device makes the robot be safely adhered to the surface of top plate,U-rib plate,and diaphragm plate,and then do the crack image capture flexibly according to the pre-set route or manual controlling route.The image processing platform,which is mainly composed of wireless industrial cameras and laser ranging self-calibration device,collects the crack images and calibration data so that the internal and external parameters of cameras can be calculated in real time.During the post-processing,the image processing platform can perform the crack identification and crack geometry measurement based on neural network training and homography matrix calculation,and the panorama picture of cracks can be further generated by using image stitching techniques.The developed system is used to collect and measure the fatigue cracks in a full-scale orthotropic steel bridge deck,and results show that all cracks in various locations can be accessibly measured.The relative errors of rule validation measurement are within 0.2%,and the average error is merely 0.14%,indicating that the crack resolving reached sub-millimeter level.Compared with traditional approach,the developed fatigue crack image routing inspection and measurement system has the advantages of high precision,automatic processing,and full coverage of inspection area,and can be applied in real bridge practice.