室内大靶面光电立靶技术研究

针对目前已应用的测量弹着点坐标的光电靶存在靶面小、不适用于大弹径弹丸测量的问题。采用平行点激光光束形成10m×10m的大靶面光栅光幕立靶,以FPGA构成数据采集系统,通过计算机上位机坐标识别软件,得到弹着点坐标,并提出了提高大靶面系统灵敏度和测量准确度的措施。室内靶场实弹测量实验结果表明,该方案满足室内测量弹着点坐标的测量准确度。     

激光光幕靶测速系统设计

针对室内外全天候条件下高精度测量弹丸速度的需求,设计了一种新型激光光幕靶.该激光光幕靶采用线性排列的红外激光管阵列作为发光光源,两列平行排布的红外光敏二极管作为接收器件,形成具有两个光幕的双光幕光幕靶.采用主动式光源,该测速系统测试效率高、精度高且不受天气影响,一次测量系统的CPLD数字逻辑电路可计算得到弹丸的两个飞行时间,便于互相比较和对照.野外实弹试验表明,该测速系统灵敏度高,工作稳定可靠,测试数据准确.     

基于大面积激光光幕的弹丸速度测试技术研究

针对弹道散布范围大或被测飞行物体尺寸大的测速场合,介绍了一种实现大面积有效靶区激光光幕速度测量的方法.采用圆弧柱面反射镜及置于其两共轭点上的半导体激光二极管和大面积光敏器件形成大面积有效光幕区.当高速飞行物体穿越激光光幕时,光通量的变化被转变为电信号并采集到计算机进行数据处理.文中对圆弧柱面反射镜所引起的像差及有效光幕区内的光功率密度的分布进行了建模分析;利用有效光幕区为900 mm×900 mm及500 mm×500 mm的系统分别对5.6 mm弹丸穿越动物及某大口径弹丸的速度进行了测试,并给出了试验波形及测试数据.试验表明,该测速系统具有有效光幕区面积大、灵敏度高、响应速度快、工作可靠的优点.     

激光光幕自动报靶系统的设计与实现

为了解决人工报靶精确度低和存在安全隐患等问题,介绍了一种激光光幕自动报靶系统的设计方案.该系统由激光器和光敏二极管构成激光网络进行弹丸信号检测,以FPGA为核心的信号处理电路对信号进行处理,得到弹着点的坐标和环数.该系统精度高、成本低、安全可靠,具有一定的应用价值.     

一种光幕测速信号的图像处理技术

在光幕靶精密测速系统中,提出了一种基于图像处理算法的信号处理技术,消除随机噪声对光电探测信号的干扰,从而可以精确荻取物体通过前后两光幕靶的间隔时间.该技术将间隔时间的计算转换为图像中目标物体尾部位置的计算.首先去除孤立点、毛刺等图像缺陷,得到只有一个连通区的图像,再用图像面积除以平均宽度计算物体的长度,求出对应的尾部位置.从前后光幕图像的尾部位置分别得到了物体通过前后两光幕靶的准确时间,两者相减最终得到间隔时间.实验表明系统采用该处理技术能够精确荻取间隔时间,实测的速度数据稳定、有效,测量精度可以达到0.05%.     

改善激光测速靶抗火光干扰性能的探索

本文针对激光测速靶在实际应用过程中易受火光干扰,介绍了一种采用激光调制技术和高频选频放大电路的方法来消除火光干扰.该方法在测速系统、大面积弹着点坐标测量甲等领域有广阔的应用前景.     

基于光幕靶的亚音速弹和预制破片速度测量算法

针对亚音速弹和预制破片的速度测量,本文基于光幕靶和数据采集卡组成的弹丸测速系统,研究了一种弹形信号识别算法和测量结果处理算法.对亚音速弹,算法依据分拣电平和信号时间宽度大小,能很好地识别出弹形信号和冲击波信号;对预制破片,算法依据过靶信号脉冲宽度与两靶输出信号的时间间隔,识别出预制破片的过靶信号.通过对弹形信号的相关分析处理,即得到弹丸穿过两个光幕的精确飞行时间,进而确定出弹丸速度.经实弹射击验证,算法准确有效,满足靶场测试要求.     

微型滑块轴承润滑油膜厚度光学测量系统

针对微型滑块轴承润滑试验研究测量复杂、精度低、不能实时测量等问题,提出一种微型滑块轴承润滑油膜厚度光学测量系统。通过基于平行并联机构的调节装置实现试样与玻璃盘倾角的调节与固定,上位机控制电机带动玻璃盘转动形成动压油膜。通过光栅获取玻璃盘的实时转速,通过双色光干涉法利用光流算法和基于动态时间规整(DTW)算法实现最小膜厚的同步测量。在实验环境中,该系统运行平稳,对于宽度为0.8mm的滑块,倾角调节分辨率为1/7328,利用波长655 nm和532 nm的红绿双色光合成激光作为光源,实现膜厚在线追踪,可满足稳态以及时变的试验要求。     

基于PSD的分离式长导轨直线度测量方法研究

利用分段拼接测量方法能够将PSD激光准直测量系统测量范围扩大,相较于传统长导轨直线度测量方法,该方法可同时适用于连续型导轨和分离式超长导轨的直线度测量。首先,在(-5～+5) mm测量范围内,通过激光干涉仪分别测得激光准直测量系统的接收靶在水平和竖直方向上的位移,误差均优于±(1μm+1%H)。然后,在40 m范围内与激光准直测量系统的直线度测量精度进行对比,二者水平方向直线度误差相差0.06 mm,竖直方向直线度误差相差0.13 mm。最后,在70 m分离式超长导轨上,测得水平方向直线度为0.50 mm,竖直方向直线度为0.53 mm。该方法可迅速定位和调整直线度误差极值点位置,能够较为有效地解决分离式超长导轨的直线度装配调试问题。     

CCD立靶坐标测量系统精度仿真分析

根据CCD立靶坐标测量系统的工作原理,对系统测量精度进行了理论分析,建立了系统测量精度数学模型,利用计算机仿真技术对其进行仿真计算,1 m靶面的测量精度为0.8 mm×1.0 mm;4 m靶面的测量精度为3.0 mm×3.0 mm.通过理论计算和试验结果的对比,证明该数学模型可准确描绘系统的测量精度.     

枪弹初速激光测试系统方案设计

叙述了利用激光光幕测试枪弹初速的基本原理,并对激光光幕的形成、测试电路的实现、利用微机进行高精度测速、机械装置的实现等提出了一套可行的方案.在机械装置具有足够高精度的前提条件下,该测试系统能够实现高精度枪弹初速的测试.     

弹丸着靶坐标测试系统的原理与信号处理电路

分析了4光幕交汇测试弹丸着靶坐标的原理．4个光幕分别由4个大面积光幕靶产生．大面积光幕靶的光源采用发光二极管阵列．接收部分采用PIN红外光电二极管阵列．设计的大面积光幕靶发射部分与接收部分的有效作用距离最大可以达到3m．文中给出了详细的信号处理电路．设计的测试系统用5种轻武器枪弹实弹射击，测试结果与纸靶相比较，其测量误差满足目前枪弹产品检验试验的要求．     

基于伺服控制的三维塑封系统

目的为了提高枪弹的防护性和可靠性,设计一种基于伺服过程控制的枪弹塑封包装系统。方法将伺服过程控制、自动枪弹包装系统与塑封包装工艺相结合,形成一种新型枪弹包装系统。结果基于伺服过程控制的枪弹塑封包装系统定位精度高,塑封尺寸和厚度控制在0.01 mm。经过900万发枪弹实运行包装验证,建成了一条新型枪弹包装系统。结论基于伺服过程控制的枪弹塑封包装系统达到了枪弹包装工艺要求,并且可靠、稳定,减少了操作人员,实现了人机隔离。     

相对冲击位置和补片层数对胶接修理CFRP复合材料层合板抗冲击性能的影响

本文针对碳纤维增强聚合物（CFRP）复合材料修补结构,基于连续损伤力学和粘结单元模型,在ABAQUS软件中对低速冲击载荷下不同冲击位置和补片层数的CFRP复合材料层合板内部和层间损伤进行了数值分析,并与试验结果进行了对比。选择相对冲击位置为0 mm、10 mm、20 mm、30 mm和40 mm时对应的五种修补结构,通过数值计算和试验,获得了修补结构在低速冲击过程中的冲击力、冲击能量等数据。在保持补片单层厚度不变的前提下,使补片层数从1层增加到5层,计算获得了修补结构的低速冲击响应。研究结果表明:冲头接触修补结构时会对补片造成较大的损伤,补片可以提高含孔损伤母板的抗冲击性能;冲击点离修补结构损伤孔越近,结构受冲击所产生的分层损伤越严重;增加补片的层数可以提高修补结构的抗冲击性能;通过对补片层数进行优化,得到优化层数为2,其对应的修补结构与无修补结构相比分层损伤面积减少了19.9%,较好地提升了母板的抗冲击性能。      

Ballistic behavior of high hardness perforated armor plates against 7.62 mm armor piercing projectile

In this paper, some of the important defeating mechanisms of the high hardness perforated plates against 7.62 × 54 armor piercing ammunition were investigated. The experimental and numerical results identified three defeating mechanisms effective on perforated armor plates which are the asymmetric forces deviates the bullet from its incident trajectory, the bullet core fracture and the bullet core nose erosion. The initial tests were performed on the monolithic armor plates of 9 and 20 mm thickness to verify the fidelity of the simulation and material model parameters. The stochastic nature of the ballistic tests on perforated armor plates was analyzed based on the bullet impact zone with respect to holes. Various scenarios including without and with bullet failure models were further investigated to determine the mechanisms of the bullet failure. The agreement between numerical and experimental results had significantly increased with including the bullet failure criterion and the bullet nose erosion threshold into the simulation. As shown in results, good agreement between Ls-Dyna simulations and experimental data was achieved and the defeating mechanism of perforated plates was clearly demonstrated.     

Dissipation of energy by bulletproof aramid fabric

The bullet resistance of laminates comprised of several layers of aramid Armos fabric has been studied. The high bullet resistance of the fabric is caused by the pulling-out of yarns impacted by the bullet. The pull-out zone is cross-shaped, the centre being the impact point. The length and the width of the pull-out zone was determined for each fabric layer. Energy transferred to fibres increases with the volume of the pull-out zone. Water reduces the bullet resistance of laminates owing to reduction of the width of the zone. The length of the pull-out zone is shorter if the transverse displacement of layers is restricted. At a projectile velocity of 420 m s-1, Armos yarns do not break immediately on impact, and the longitudinal wave propagates along the fibre. Friction of yarns in aramid fabric was studied by a yarn pull-out method. This revised version was published online in November 2006 with corrections to the Cover Date.     

智能化激光显示系统的设计与研究

研制了一套由激光器,图形输入仪,控制计算机,驱动器,光学工作台及大屏幕等六个部分构成的激光显示系统。理论研究得出,大屏幕所显示图形上的任意点P,均存在一与之对应的振镜偏转角确定值,精确控制振镜的偏转角即可扫描到P点。实验表明,系统可成功实现诸如函数图形、光栅衍射图案、光网光柱及文字动画等多功能智能化激光视频图像的动态输出。     

Analysis of morphology and microstructure of B4C/2024Al composites after 7.62 mm ballistic impact

The effects of ballistic impact on morphology and microstructure of B₄C/2024Al composites were studied. B₄C/2024Al composites with 55% volume fraction of B₄C particles were prepared by pressure infiltration method, and the experimental test of ballistic performance of composites was carried out by 7.62 mm armor piercing projectiles. The obvious upsetting of bullet and furrows on bullet tip are generated after bullet impact. Moreover, bared B₄C particle distributes uniformly on the bullet surface, indicating that the composites target plays roles of passivation and abrasion on bullet. The protection coefficient of B₄C/2024Al composites shows trends of falling, then an upward trend, at last keeping constant as the increasing thicknesses of targets, and could reach up to 2.8. For the composites target with semi-infinite thickness, three kinds of failure morphology are presented at the bullet crater: caving, erosion and melted areas, spreading successively as the increasing depth, which indicates that the interaction between bullets and targets is different at different stage of bullet penetration. Interestingly, the interface bonding of composites keeps well after bullet impact; moreover, no interface de-bonding was observed. High density of dislocation is generated in Al matrix around the interfaces, meanwhile, dislocations and micro-cracks were found in some B₄C particles.     

SRM 2460/2461 Standard Bullets and Casings Project

The National Institute of Standards and Technology Standard Reference Material (SRM) 2460/2461 standard bullets and casings project will provide support to firearms examiners and to the National Integrated Ballistics Information Network (NIBIN) in the United States. The SRM bullet is designed as both a virtual and a physical bullet profile signature standard. The virtual standard is a set of six digitized bullet profile signatures originally traced from six master bullets fired at the Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI). By using the virtual signature standard to control the tool path on a numerically controlled diamond turning machine, 40 SRM bullets were produced. A profile signature measurement system was established for the SRM bullets. The profile signature differences are quantified by the maximum of the cross correlation function and by the signature difference between pairs of compared profile signatures measured on different SRM bullets. Initial measurement results showed high reproducibility for both the measurement system and production process of the SRM bullets. A traceability scheme has been proposed to establish the measurement traceability for nationwide bullet signature measurements to NIST, ATF and FBI. Prototype SRM casings have also been developed.     

紫外激光对触摸屏产品中不可视区域刻蚀实验研究

采用紫外激光对触摸屏产品中不可视区域进行刻蚀分析,探究了紫外激光刻蚀原理,讨论了银浆薄膜激光刻蚀与传统印刷工艺异同点,并在此基础上完成一套紫外激光刻蚀系统方案的设计和建造。实验结果表明,选用波长为355nm的紫外激光器,当激光器功率为10W,重复频率100kHz,刻蚀速度为1500mm/s,刻蚀次数1次时,薄膜被完全刻蚀,最终获得功能良好的银浆线路。经测试后发现,所刻蚀后银浆线条平直而光滑,边缘热影响区域较小,最小刻蚀线宽可以达到10μm,基板未受到损伤;与传统印刷工艺相比较,简化了工艺步骤,产品良品率得到提升,是一种无排放的绿色环保先进的刻蚀工艺。