激光与光电子学进展, 2020, 57 (22): 221508, 网络出版: 2020-11-05
基于单帧多次局部曝光的测速方法 下载: 622次
Velocity Measurement Method Based on Single-Frame Multiple Local Exposures
机器视觉 测速 高速摄影 光源设计 激光测距机 machine vision velocimetry high-velocity photography illumination design laser range finder
摘要
针对测量高速运动暗小目标的需求,提出了一种基于单帧多次局部曝光的测速方法。理论分析了关键参数对测量频率的影响,推导了激光照明目标的灰度成像模型表达式。利用脉冲激光作为局部曝光光源与时序基准,在单帧图像中多次生成带时间戳的目标影像;建立单帧多次局部曝光测速模型,利用单目视觉与激光测距数据实现了暗小目标的空间定位与测速,突破了高速相机测量频率的上限并提高了测量精度;对速度为1500m/s的目标进行了测速仿真实验,结果表明,测速误差小于0.7%。在低速条件下设计了样机实验,相比标准速度的目标发射器,测速误差小于2.5%,且系统成本较低、机动性好,满足工程精度要求。
Abstract
In order to meet the requirements of measuring high-velocity moving dim small targets, a velocity measurement method based on single-frame multiple local exposures is designed. The influence of key parameters on measurement frequency is analyzed theoretically, and the expression of gray imaging model of laser illuminated target is deduced. Using pulsed laser as local exposure light source and timing base, the target image with time stamp is generated in a single-frame image for many times. A velocity measurement model of single-frame multiple local exposures is established, and the spatial positioning and velocity measurement of small dark targets are realized by using monocular vision and laser ranging data, which breaks the upper limit of the measurement frequency of high-velocity camera and improves the measurement accuracy. Velocity measurement simulation experiment is carried out on a target with a velocity of 1500m/s, and the results showed that the velocity measurement error is less than 0.7%. The prototype experiment proves that the relative velocity error of target is less than 2.5% compared with the velocity of standard velocity target launcher in low velocity conditions, and the system has low cost and good maneuverability, which meets the requirements of engineering precision.
吕琼莹, 谢缘, 穆国振, 贾冰. 基于单帧多次局部曝光的测速方法[J]. 激光与光电子学进展, 2020, 57(22): 221508. Qiongying Lü, Yuan Xie, Guozhen Mu, Bing Jia. Velocity Measurement Method Based on Single-Frame Multiple Local Exposures[J]. Laser & Optoelectronics Progress, 2020, 57(22): 221508.