车辆外廓尺寸计算机视觉动态测量

A Vehicle Outer Contour Dimension Measuring Method Based on Computer Vision Technology

针对车辆外廓尺寸的精确快速测量,本文提出一种激光光幕和CCD相结合的动态测量方法。本方法采用安装在龙门架顶角的两台CCD相机快速采集被车辆高度调制垂直投射的激光点图像,并应用区域生长质心匹配算法提取边缘投影数据测量车辆的宽度;采用车身侧面序列图像拼接获取车辆侧面全景图像,并对全景图像做一阶投影差分处理精确定位车头和车尾,根据摄像机透视模型测量车辆的长度,并结合宽度边缘分布数据修正长度的测量精度;采用FPGA获取垂直安装的红外光幕侧投影数据测量车辆的高度。本方法与传统的激光雷达和红外光幕的测量方法比较,具有占用场地小,安装结构简单,抗干扰能力强和测量精度高的优点,经过车辆外廓尺寸的现场测试实验,结果表明该方法测量误差小于1%,平均耗时低于50 s,验证了本测量方法的准确性和实时性,且本方法具有较强的鲁棒性和重要的应用价值。

A dynamic measuring method for combining the laser light curtains and CCD is proposed to achieve a precise measurement of the vehicles outside dimensions. Rapidly acquisition image of the laser spot light curtain is modulated by vehicles height with CCD cameras mounted gantry vertex, and extract the vehicle distribution data of the edge based on region growing centroid matching algorithm to measure vehicle width. Secondly, a sequence of images with mosaic method is used to get the vehicle panoramic image, and pinpoint the front and rear of vehicle by panoramic image projected first-order differential, then depending on the camera perspective model to measure the length of the vehicle, combined with a width edge distribution data to correct the length accuracy. Obtain infrared light curtain vertically mounted projection data via FPGA processing system to measure vehicle height. The measurement method have the advantages of a space occupied by small, simple installation structure, strong anti-jamming capability and high accuracy measurements compared with traditional measurement methods of laser radar and infrared light curtain. The results of the outer contour of the vehicle size measuring test show that the measurement system error is 1% and the average time-consuming is lower than 50 s. Verify the accuracy and real time of this measurement method, and this measurement method is robust and important applications.