作者：宋小春1, 王凯1, 熊芝1, 罗付国2
作者单位：1. 湖北工业大学机械工程学院, 湖北 武汉 430068;
2. 东风商用车有限公司, 湖北 十堰 442001
关键词：视觉测量; 区域划分; 伺服定位; 坐标归一化; 汽车大梁
摘要：
为实现对汽车底盘大梁上装配孔孔径和孔位尺寸的自动测量,设计基于伺服定位技术的视觉测量系统。基于大梁CAD设计图上装配孔的分布特征,划分目标图像采集区域,提取拍摄单帧图像时相机的位置坐标,并以该坐标值控制伺服电机运动和启停,触发相机采集目标图像;同时,伺服电机编码器反馈位置坐标给驱动器,为图像测量提供位置基准,对单帧图像上装配孔的圆心坐标进行归一化处理,从而实现对整个大梁尺寸的自动测量。实验结果表明:该系统对大梁装配孔的孔径尺寸测量误差约0.30 mm、孔位尺寸测量误差0.90 mm,能够实现汽车大梁关键尺寸非接触、全自动测量。
Vision measurement system for automobile chassis crossbeams based on servo positioning technology
SONG Xiaochun1, WANG Kai1, XIONG Zhi1, LUO Fuguo2
1. School of Mechanical Engineering, Hubei University of Technology, Wuhan 430068, China;
2. Commercial Vehicle Company, Dongfeng Motor Co., Ltd., Shiyan 442001, China
Abstract: In order to measure the diameter and location dimension of assembly holes on automobile crossbeam automatically, a vision measurement system based on servo positioning system was designed. Firstly, the region for target images acquisition was divided based on the designed CAD drawing of crossbeams, and the position coordinates for camera shooting a single frame image was extracted respectively. Then, the coordinates were used to drive the servo motor moving and start-stop by motion control card, and trigger the camera shooting target images. Meanwhile, the position coordinates, used as the position reference to normalize the center coordinates of assembly holes in each frame image, were feedback from the servo motor encoder. Thus, the assembly holes of whole crossbeam can be sized accurately. The experimental results show that the measurement deviations of diameter and location dimension of assembly holes are below 0.3 mm and 0.90 mm respectively, and the system can realize non-contact and automatic measurement for key dimensions of automobile chassis crossbeams.
Keywords: vision measurement; region division; servo positioning; coordinates normalized; automobile crossbeam
2015, 41(1): 93-96 收稿日期: 2013-11-25;收到修改稿日期: 2014-1-16
基金项目: 国家自然科学基金项目(51305130)
作者简介: 宋小春(1972-),男,湖北应城市人,教授,博士,主要从事工业测控与现代无损检测技术研究。
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