用于高速碰撞过程拍摄的5万帧摄像系统设计  

Design of 50000 fps camera system for shooting of high-speed collision process

作　　者：史魁[1,2] 杨洪涛 彭建伟[1] 王浩 闫阿奇[1] SHI Kui;YANG Hong-tao;PENG Jian-wei;WANG Hao;YAN A-qi(Xi′a n Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi′a n 710119,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院西安光学精密机械研究所,陕西西安710119 [2]中国科学院大学,北京100049

出　　处：《光学精密工程》2023年第1期69-77,共9页Optics and Precision Engineering

基　　金：国家重点研发计划资助项目(No.2016YFC0803000);国家自然科学基金资助项目(No.51905529)。

摘　　要：为了近距离清晰拍摄某高速运动目标的碰撞过程,研究了一种高帧频摄像系统。由于摄像系统的前端可能遭受碰撞碎片的损坏,研究了一种保护窗组件。针对成像单元的FPGA在极端高温+70℃时温度过高的问题,研究了一种导热装置。采用七组成像单元在顺序脉冲的控制下接续拍摄的方法,实现了5万帧/秒的高帧频成像。保护窗组件采用了三组保护窗玻璃自动移动更换且可自锁的形式,采用蜗轮蜗杆传动机构实现了大传动比驱动和自锁功能,采用霍尔传感器对保护窗的位置进行实时反馈。导热装置中间部分采用了柔性的高热导率石墨板,既有效地将FPGA的热量传导至主壳体上,又解决了装调节环节中刚性导热装置的过定位问题。对装配好的高帧频摄像系统进行了相关的力、热实验。实验结果表明,保护窗组件自锁和移动切换功能正常,高帧频摄像工作正常,实测拍摄帧频为50 050帧/秒,满足近距离清晰拍摄某高速运动目标碰撞过程的要求,具备一定的防护能力和热环境适应能力。In this study, a high-frame-frequency camera system is investigated to closely capture the collision process of a high-speed moving target. As debris from the collision may get stuck to the front of the lens, a protective window assembly is considered. A thermal conduction device was also investigated because the temperature of an FPGA installed in the imaging unit is too high, with a maximum temperature of 70 ℃. A method for continuous photography with seven image units under the control of a sequence pulse was proposed,and the camera system achieved high frame-frequency imaging of 50,000 fps. The protective window assembly included three sets of self-locking protective window glasses that move automatically. A worm gear was utilized to realize a large transmission ratio and self-locking function, and a Hall sensor was used to report the position of the protection window in real time. The middle part of the heat conduction device comprised flexible graphite plate with high thermal conductivity. Thus, the heat of the FPGA was transmitted effectively to the shell, and the problem of over-positioning of rigid heat conduction devices was solved during the installation and adjustment of the device. Vibration and heat tests were carried out on the assembled model camera. During and after the tests, the self-locking,movement and switching of the protective window component function properly, the camera works normally, and the measured frame rate is 50050 frames/s. Hence, the camera system meets the requirements for clearly recording high-speed collisions, and provides a certain protection ability as well as adaptability to different thermal environments.

关 键 词：摄像系统 高帧频 保护窗 蜗轮蜗杆 热设计 石墨膜 

分 类 号：V245.6[航空宇航科学与技术—飞行器设计]