基于线结构光扫描的结冰冰形三维测量

Ice 3D Shape Measurement with Line Structured Light Scanning

中文关键词:  结冰风洞  冰形测量  线结构光  激光中心线

英文关键词:icing wind tunnel  ice shape measurement  line structured light  laser center line

中文摘要:

      现有三维扫描仪进行结冰冰形测量时需喷涂显影剂，无法满足结冰生长过程3D冰形在线测量需求。为此，基于线结构光扫描，提出了结冰冰形三维测量方法，搭建了基于传送带的线结构光扫描冰形测量装置，对线结构光视觉测量系统进行标定，获取了摄像机和激光平面方程参数，采用改进的梯度重心法实现了低对比度冰体图像激光光带亚像素中心位置提取，结合标定结果计算了冰体轮廓线三维坐标，再根据传送带运动距离，对冰体轮廓线逐行拼接，得到整个冰体三维测量点云。实验结果表明，对半径已知的圆柱形冰块进行轮廓线测量，相对误差为0.157 mm。

英文摘要:

      The existing 3D scanner needs to spray developer when measuring ice shape,which can not meet the needs of 3D ice shape on-line measurement in the process of ice growth.Therefore,an ice 3D shape measurement with line structured light scanning is proposed.A line structured light scanning ice shape measurement device based on conveyor belt is built,the line structured light vision measurement system is calibrated,the camera and laser plane equation parameters are obtained.And the sub-pixel center position extraction of laser light belt in low contrast ice image is realized by using the improved gradient center of gravity method.Combined with the calibration results,the 3D coordinates of the ice body contour are calculated,and then the ice body contour is spliced line by line according to the moving distance of the conveyor belt to obtain the 3D measurement point cloud of the whole ice body.The experimental results show that the relative error of contour measurement for cylindrical ice with known radius is 0.157 mm.