风洞模型位移视频测量的相机标定  

Camera calibration of model displacement videogrammetric measurement in wind tunnel

作　　者：王爱玲[1] 张征宇[1] 黄诗捷[2] 王水亮[2] 赵涛[2] 

机构地区：[1]中国空气动力研究与发展中心空气动力学国家重点实验室,四川绵阳621000 [2]西南科技大学信息工程学院,四川绵阳621010

出　　处：《实验流体力学》2012年第5期74-78,共5页Journal of Experiments in Fluid Mechanics

基　　金：四川省科技创新苗子工程;国家自然科学基金(51075385)

摘　　要：相机的制造和装配误差难以完全消除,导致相机的光学系统存在不同程度的非线性光学畸变现象,故相机标定对确保风洞模型位移视频测量的精度至关重要。针对1m2以上的台阶标定块制造成本高、维护困难,提出基于距离标尺的相机标定方法,推导包含非线性畸变模型的共线方程,建立适应中国大尺寸风洞的低成本相机标定系统,确保模型位移视频测量相机的自校正精度。2m超声速风洞的某跨大气层飞机测力试验中,采用该方法校正DALSA○R相机后,各阶梯迎角测量精度σα≤0.00772°(达到高速风洞测力试验迎角精度的先进指标),因此具有实用价值。Camera calibration is crucial for the measure precision of model displacement in wind tunnel test, because the fabricating and assembling errors of the camera optical system can- not be removed which results in nonlinear distortion between real image and ideal image to some extent. When the area of calibration target-plate is more than lmz ,its cost of fabrication and ma- intenance is very high, therefore, a camera calibration method based on known distance ruler is introduced. Collinear equations with nonlinear distortion coefficients are deduced to ensure self- calibrating accuracy, and the low-cost calibration system is constructed. The videogrammetric an gles of attack for an orbiter model in 2m supersonic wind tunnel test, which uses this method to calibrate two DALSA cameras, have demonstrated σa≤ 00772°（reach the advanced precision of attack angle for high speed wind tunnel）, therefore it is useful and effective.

关 键 词：模型位移测量 风洞试验 相机标定 测量精度 误差分析 视觉测量 

分 类 号：O432.2[机械工程—光学工程]