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本文介绍高速摄影法测量弹丸破片飞散速度的几种方法,着重讨论了直接摄影法,它能显示破片在距起爆弹丸较近距离上的防影图象,经数据处理,可获得诸破片速度大小的分布值,还可望求得同一破片在其飞行轨迹上的速度衰减量。 相似文献
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本文叙述了某新型飞机在设计研制过程中,需要对翼下挂架投放机构进行运动分析的课题,利用高速摄影测量技术进行全过程的实测分析。文章叙述了摄影测试的原理、方法。着重讨论了摄影测量中一向被人们所忽视的场地测量与校验。认为等待型摄影测量中,摄影比例尺的精度除与所用设备的精度有关外,还与场地测量精度有关。在动态摄影测量中,测试方法、测量场地布置与控制点的建立,以及时间量的正确量测,对摄影测试精度有很大影响。 相似文献
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在常规兵器试验中,利用现有的电影经伟仪和弹道相机无法完成弹目交会过程及姿态、子母弹抛撒和子弹的飞行姿态等项目的测试,但将高速摄影机与其它仪器(如经伟仪跟踪架)、设备技术结合起来即高速立体摄影可完成对其测量。高速立体摄影测量是以立体摄影测量为基础,使用高速摄影机进行的摄影测量。与普通立体摄影测量相比,两者存在许多相同或相似的地方,如理论分析、计算方法、判读等。但由于使用高速摄影机,在摄影测量中,摄影机的选择和使用,目标与摄影机的同步,多台摄影机的同步,底片的处理方法和数据处理方法等一些问题,都需要研究和解决。本文对这些问题进行了讨论。 相似文献
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本文介绍了单片机控制的GS-221高速摄影测量仪数据记录系统的工作原理、硬件设置和主要的软件流程。 相似文献
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本文提出单机正交三维高速摄影研究家蝇追逐飞行规律的方法,并用旋转法重现三维飞行轨迹。报告在自由飞行条件下雄蝇追逐行为实验及其初步分析结果。 相似文献
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高速摄影技术对水中气泡运动规律的研究 总被引:19,自引:3,他引:16
气泡在许多不同过程中起着重要作用.舰船尾流中的气泡提供了这样一个线索,即基于对气泡的特性研究,并以此对舰船进行追踪是一种独特的方法.用高速摄影技术来研究气泡,具有直观、低费用的优点,配合以半自动胶片判读仪,可获得较为详细的关于气泡的参量.实验结果表明,水中气泡上升速度的大小都在随时间减小,气泡的末速度存在一极值,它与一定大小的气泡相对应.文中详细讨论了水中气泡的动力学特征,并与高速摄影所得到的气泡图象数据进行了比较,其结果的一致性肯定了高速摄影技术对水中气泡运动规律的研究中的重要性 相似文献
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应用高速摄影观测运载基因子弹的运动速度,采用彩色摄影解决了黑白底片在放电时产生烟雾而使图像分辨不清的问题。通过多次实验改进了射腔结构和子弹的形状,从而获得了最佳运动速度。这种方法简单易行,解决了电测法由于高压放电产生的干扰问题以及多种模拟装置的高压放电与控制系统的同步问题。 相似文献
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This paper addresses optimization of a high-speed digital feedback controller for a plasma position in Damavand tokamak. Damavand
tokamak discharges have plasma currents up to 40 kA with discharge duration greater than 15 ms and toroidal magnetic fields
up to 1.2 T. The plasma position is measured using saddle-loops and Rogowski coil and is controlled by electromagnetic forces
generated by passing currents through control coils placed around the plasma. A desired control objective is maintaining the
plasma in the center of vacuum vessel and to stabilize the plasma in the presence of disturbances in a time domain of the
order of few milliseconds. In order to achieve maximum performance it is essential to optimize the control system. In this
paper plasma position measurement and the details of implementing high-speed PID controllers based on a TMS320c25 digital
signal processor along with the system optimization are presented. 相似文献
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Steven M. Barlow Greg Suing Alex Grossman Peter Bodmer Raymond Colbert 《Journal of voice》1989,3(4):283-293
Many laboratories designed to assess vocal tract function are still dependent on FM tape recorders, strip chart recorders, and analog oscilloscopes. Data reduction is often a tedious process requiring time-consuming manual measurement routines. The present report describes the components of a high-speed computer system for real-time data acquisition and display, stimulus control, and automated analysis. The acquisition and computational performance of this system is exemplified in a discussion of two special-purpose software applications, including (a) speech aerodynamics and (b) orofacial force physiology. 相似文献
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Inaccuracies in the calibration of a stereoscopic system appear with errors in point correspondences between both images and inexact points localization in each image. Errors increase if the stereoscopic system is composed of wide angle lens cameras. We propose a technique where detected points in both images are corrected before estimating the fundamental matrix and the lens distortion models. Since points are corrected first, errors in point correspondences and point localization are avoided. To correct point location in both images, geometrical and epipolar constraints are imposed in a nonlinear minimization problem. Geometrical constraints define the point localization in relation to its neighbors in the same image, and eipolar constraints represent the location of one point referred to its corresponding point in the other image. 相似文献
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针对控制系统软件在线更新或升级维护的需要,构建了SoPC远程更新系统,研究了一种远程在线更新FPGA硬件配置文件和Nios II软件可执行文件的可重构方法。通过硬件配置代码和软件可执行代码引导顺序的分析,设计了高级BootLoader,可以从任意指定地址加载应用模式映像软件代码;EPCS存储用于远程更新的工厂模式映像和多份用于天线相位控制的应用模式映像;采用自定义的CAN应用层协议,用于传输及校验数据,保证了传输的可靠性。实验验证了方案的可行性,系统可进行多份配置程序的自由切换;即使远程更新失败,FPGA也能自动加载工厂模式映像,提高了系统安全性和可靠性。 相似文献
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A nulling interferometer was proposed to achieve direct detection of extra-solar planets (exoplanets) by suppressing light from the central star using a pair of telescopes. Recently, the stellar coronagraph method has shown rapid progress, which uses an extended concept of the nulling interferometer within single telescope optics. A dynamic range larger than 1 × 109 for the detection of Earth-like exoplanets can be attained by reducing diffraction patterns using the nulling coronagraph, and by suppressing speckle noise using an adaptive optics with an accuracy of λ/10000 rms. An unbalanced nulling interferometer (UNI), which is used as fore-optics, improves the wavefront sensing sensitivity and compensation level of the adaptive optics by a factor of 10. Consequently, the dynamic range of the coronagraph can also be improved by two orders of magnitude. The UNI is composed of a modified coronagraph or a traditional interferometer and magnifies the aberrations of incoming wavefronts. 相似文献
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Olaf Kster Bernd Marx Peter Gemmar Markus M. Hess Hermann Josef Künzel 《Journal of voice》1999,13(3):355-374
High-speed filming is one of the most informative methods for assessing voice physiology data. Tracing high-speed images of the glottis provides quantitative parameters such as the glottal area and the glottal width function. By way of example, a number of studies are discussed which extract quantitative data from high-speed images showing voice onsets. Furthermore, a new computer system (MVAS; multi-dimensional voice analysis system) is presented that synchronously displays a laryngoscopic high-speed film, the electroglottographical signal, and several acoustic analyses of the recorded voice sample. The automatic measurement of glottal width and glottal area from the laryngoscopic images is also provided. Looking at former studies and our analyses of voice onsets reveals a tremendous intersubject and even intrasubject variability (different prephonatory closure, different time span until full amplitude is reached, different open quotient). 相似文献
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为了提高光电跟踪系统的跟踪精度,对其粗跟踪环节的共轴跟踪控制技术进行了研究。介绍了共轴跟踪控制的基本原理,分析了常用非线性卡尔曼滤波算法,并仿真比较了无迹卡尔曼滤波(UKF)和容积卡尔曼滤波(CKF)的位置和速度的预测精度。在此基础上综合UKF和CKF的优点,设计了对延迟的合成位置信号进行处理的双并联滤波器,实现了光电跟踪系统的共轴跟踪控制。利用实测数据仿真实验表明,光电跟踪系统的跟踪精度明显提高。 相似文献