高速风洞试验中的视频测量技术进展
Progress of videogrammetric measurement techniques for high speed wind tunnel test
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摘要: 视频测量(Videogrammetry)技术因其对试验模型设计无特殊要求,受到国内外风洞试验机构的青睐。本文在介绍视频测量的理论基础之上,面向高速风洞试验的振动噪声环境,分析了飞行器精细化风洞试验对视频测量技术的需求,综述了大角度大重叠数字图像的外方位元素解算、标记点及其图像处理、相机标定和气动光学波前畸变场测量等技术进展。在2m 量级的高速风洞中,通过多个工程实例表明:视频测量的精度高,同期试验迎角视频实测数据的标准差≤0.0075°;同期动态变形实测数据的标准不确定度为5.232±0.082mm;为气动光学效应的研究与测量提供了新途径,其光路简单、无需使用价格昂贵的相干光源。Abstract: Videogrammetric measurement for wind tunnel test is research focus at home and abroad because it has no special requirements on the test model.The key technical progresses of the videogramnetric measurement for the vibration environment of the high speed wind tunnel are introduced in this paper,such as the solution of exterior parameters in big-angle large overlap, the algorithm of image processing for extracting marked point,the method of camera calibration and wave-front distortion field measurement.The great application prospects of videogrammetric measurement in 2m size high-speed wind tunnel test are demonstrated by several practical cases, which show that the precision of the videogrammetry is high,that is,the standard deviation of angle of attack is equal to or smaller than 0.0075°;the standard uncertainty of the deformation data is 5.232±0.082mm;videogrammetry provides a new way to research on and measure aero-optic effects.The method which is simple and does not require expensive coherent light sources.