渔具模型空间形状的计测方法  

A method for measuring 3D geometry of fishing gear models in the flume tank based on video image analysis

作　　者：万荣[1] 宋协法[1] 唐衍力[1] 胡夫祥 东海正 

机构地区：[1]中国海洋大学水产学院,山东青岛266003 [2]东京水产大学海洋生产学科

出　　处：《水产学报》2004年第4期443-449,共7页Journal of Fisheries of China

基　　金：国家高技术研究发展计划(863计划)项目(2001AA623010);山东省优秀中青年科学家奖励基金

摘　　要：为便于对渔具作业形状的数值计算结果的精度评价提供更详细的实验验证数据,提出了利用2台数码摄像机同时从实验水槽的下方和侧面立体拍摄渔具模型展开形状的实验方法和通过图像解析装置及软件读取各节点的位置坐标并进行误差修正的解析方法。利用本方法得到的一系列节点位置坐标和自行编制的计算机绘图程序,不仅可以方便地进行水流中渔具模型的二维或三维展开形状的虚拟呈现,而且还可以任意地将图形进行旋转、放大和缩小,以对渔具展开形状的各个局部进行比实际模型试验更为详细的观察和比较。通过对实验例的比较和分析,表明本方法具有较好的精度和实用性。A method was proposed to measure the 3D geometry of fishing gear model in the circulating water tank for verifying the accuracy and validity of our numerical method for flexible fishing nets. Images of the working shape of the model were taken by two digital video cameras and analyzed by means of a so-called'DIP-MOTION 2D' digital image analysis software, in order to produce a set of 3D coordinates for all measured nodes. The errors resulting from distortions by water refraction and parallax have been corrected except one from the distortion of the image by the camera lens. The 3D geometry of the models in a current that are reproduced using the found coordinates by a developed program can be rotated and enlarged in PC display. Considering the size limit of the water tank and the need of experimental observation, as illustrative examples, a simplified longline model only having three branch-lines and a plane netting model (10×6 meshes, mesh size of 400mm) were used, and the corresponding model test was respectively conducted in a flume tank at Tokyo University of Fisheries. The comparative experimental investigations have proved the validity of the proposed method.

关 键 词：渔具模型 空间形状 计测方法 图像解析 偏差修正 数值模拟 

分 类 号：S972[农业科学—捕捞与储运]