某机载高速影像测量系统精度分析方法及验证

根据某机试飞测试需求,需要在弹舱内采用摄影测量方法,在弹舱内相应位置安装高速摄像机,采用双目立体交会测量方法测试飞机不同高度下武器投射试验,检测武器舱的弹射武器分离过程、速度、姿态等.为了估算机载高速影像测试系统的精度,保证试飞测试的科学性和严谨性,提出了机载高速影像测量系统测量精度的理论分析方法,并通过设计测量自由落体的速度及精密转台的角速度两个实验,对所提出的理论分析方法进行了验证.实验结果表明,所提误差分析方法对某机载高速影像测试系统具有指导作用,为后续试飞中的测量精度估算提供了理论支撑.     

多目标立靶密集度测试技术研究

双CCD交汇立靶密集度测试系统是靶场测试火炮密集度的常用方法,但该系统仅能测试单发弹丸的着靶坐标,对于两发或两发以上弹丸同时着靶,该系统无法测试。本文在研究双CCD交汇立靶密集度测试方法的基础上,提出了三CCD交汇测量方法,能够解决双CCD交汇测量系统的不足,实现多发弹丸同时着靶条件下的立靶密集度的测试。该研究方案成功后不但可以解决双35高炮这类双管武器性能测试的问题,亦可以用于多管连发式武器立靶密集度测试。     

转管自动机机心加速度测试系统的研究

转管武器机心加速度参数是研究其可靠性的重要依据,针对由转管自动机机心结构限制引起转管武器机心加速度无法直接测量的问题,以存储测试技术为理论指导,设计了一套具有低功耗、多种触发方式可编程的加速度测试系统,对转管武器机心结构进行特定的改造使测试仪可安装在其相应位置完成测试工作。并通过实际试验测得了完整的三轴加速度曲线,验证了转管武器加速度测试系统的可靠性,为凸轮曲线、机心的改进设计提供了有效的实验数据。     

用于测量激光烧蚀下靶材获得冲量的方法

强激光与固体靶物质相互作用产生的等离子体膨胀对靶有强烈的反冲作用,这就是激光等离子体推进的基本思想。固体靶获得冲量大小的测量在研究冲量传递效率过程中有重要作用。采用一种悬摆法和光电测速法相结合的测量方法对激光等离子体膨胀时靶摆动的周期、角速度进行了实验测量,结合测试装置的几何结构和流体力学理论得到了有空气阻力影响下靶的摆动方程,并将实验测量的靶摆动周期与由摆动方程计算的结果进行了比较,两者之间的相对误差小于0．5％,即这一摆动方程能较精确地描述靶的摆动过程,采用此摆动方程和实验测量的靶摆动角速度求得了靶的冲量。理论和实验研究结果表明该测试方法具有结构简单、操作方便、测量精确度高等特点。     

激光平行光幕光能分布均匀性测量研究

激光平行光幕用途广泛,可以用来测量物体的直径,弹丸的速度、坐标、弹丸着靶密度等.光幕面内光能分布不均匀使得计时误差较大,直接影响测量精度.光幕光能分布均匀性的测量主要是为研究更大规模的光幕靶和密集度靶提供必要的数据准备和理论基础,有助于提高光幕测试的精度.从理论上介绍了激光光斑能量分布情况,对激光平行光幕的设计原理进行了说明,完成了激光平行光幕光能均匀性的测量实验,并使用origin软件对测量数据进行了分析.实验结果与理论分析相符,证明了测量方法的可行性.     

基于激光回馈干涉系统的PZT迟滞特性测量

压电陶瓷迟滞特性对精密控制系统的精度具有重要影响,目前PZT迟滞特性的测量方法精度较低或者测量系统复杂,难以实现高精度测量。总结分析了目前测量压电陶瓷特性的方法,并使用基于激光回馈干涉原理的微片激光回馈干涉测量系统,利用物体表面的散射光对压电陶瓷的迟滞特性进行测量和分析。该方法不需靶镜,对被测对象要求较低,测量便捷,测量精度达到纳米量级,对精密控制系统中压电陶瓷的校准测量具有重要意义。     

频谱分析仪测量相位噪声研究

随着相位噪声测量技术的发展,不断有采用新技术的测量系统被开发出来,但基本的测量原理仍具有其优势并得到广泛应用。本文阐述了利用频谱分析仪测量相位噪声的几种基本方法,从原理上对测量方法进行了推导分析,并分析了每种测量方法的优缺点。在文章最后介绍了易于搭建的载波滤除测量方法,通过搭建测试平台进行实际测量验证了此方法的可,存胜。     

考虑液压扰动的水下机械手空间转角六点测量方法

提出了一种“空间转角六点测 量方法”,在机械手被测关节上固定六个靶标点,通过立体视觉方法计算出转动起始与结束 两个位置的靶标 三维中心坐标,先进行液压扰动的位姿矫正,再计算该关节的实际转角,并在此基础上开发 了一套完整的 基于多目立体视觉的测量系统。通过模拟测量实验,证明了在测量水下机械手的关节转角时 ,本文提出的“六 点测量方法”可有效消除扰动的影响,其中在计算空间角时所采用的投影法优于单位四元数 算法,其在空间 点测量误差范围为(－2,2)mm的情况下角度测量误差为0. 037。最后通过对某型号水下液压机械手关节转 角范围的现场测试验证了所提出的测量方法的可行性及其精度。     

强激光作用靶材冲量的测量方法

本文主要是对激光作用靶材的冲量进行了研究。提出了两种测量方法,研制了相应的测量仪器。对激光在大气条件下作用于铝靶产生冲量的情况,进行了初步的实验研究。 用锗透镜把高能脉冲CO_2激光束聚焦,在靶表面上,用两种方法测量对靶的冲量。 一、激光测速刚体转距法。一个绕固定轴转动的刚体靶,受TEA CO_2脉冲激光辐照,在一瞬间由静止达到某一转速ω。此时靶所受冲量为:f·⊿t=Iω/L,其中I为靶的转动惯量,L为力臂,转速ω是主要测量参数。     

基于双目视觉的导弹着靶参数测量研究

为解决靶场中导弹着靶参数无法快速精确测量的难题,提出基于双目视觉的导弹着靶参数测量方法。利用高速数字摄像机和控制部件构成测量系统的＂双目＂,实时记录导弹着靶景象。建立地心直角坐标空间中直线交会测量模型,利用图像目标提取和定位技术,可使计算机在较短时间内处理出导弹的着靶参数。实验证实,该测量方法具有操作简便,测量精度高,处理速度快的特点。     

Error analysis techniques for planar near-field measurements

A combination of techniques is described for reliably estimating the magnitude of each error arising in planar near-field measurements. They include mathematical analysis, computer simulation, and measurement tests. There are three primary applications for these tests: in designing a measurement facility, the requirements of each part of the measurement system can be specified to meet a given level of accuracy; during actual measurements, the experimenter can identify, and reduce where necessary, potential sources of error in the measurement; and when a measurement has been completed, the estimated uncertainty in the measurement can be obtained with confidence and ease. The latter application has been used in many measurements to verify that the planar near-field technique produces high-accuracy results competitive with any other measurement technique     

Reliability Verification in a Measurement System of Integrated Varactors for RF Applications

In this paper the reliability verification in a measurement system of passive components is presented, the passive components measured are integrated varactors. The measurement system used for the characterization of the varactors consists of the HP8719ES Vector Network Analyzer. To calibrate the measurement system, the short-open-load-through (SOLT) was used. The varactors have been designed with measurement structures in order to use the Cascade ACP40 GSG microprobes. The de-embedding process is used to move the measurement reference plane from the calibration point (probe tips) to the DUT (Device Under Test). For this work, it was used the Four Step De -embedding method but after making the necessary measurements the method has been simplified by not taking into account the coupling between signals due to tits very low value. Also, the characterization of the connections leads has not been done using the test structures but using the design rules. Due to the measurement system introduces uncertainty in the varactor measure, is necessary design some tests in order to calculate the error. In this paper these tests are defined.     

环境应力筛选中的温度测量研究综述

温度是环境应力筛选试验中所采用的最主要应力,精确的温度测量会密切地影响到环境应力筛选试验的效能。分析了各类温度测量方法,探讨了将热电偶用于环境应力筛选温度测量的方法,并给出相应温度测量系统的简要设计方案。     

Time difference amplifier

Accurate measurement of edge time differences down to 10 ps or less is required for tests of timing in digital systems. A circuit is described that is aimed at reliably amplifying these time differences by a factor between 3 and 10 before measurement to enable greater accuracy.     

Wafer level reliability: Process control for reliability

Wafer Level Reliability test techniques can be used to provide fast feedback process control information regarding the reliability of the product of a semiconductor process. The purpose of wafer level reliability (WLR) tests is the measurement of variation in the materials comprising the semiconductor device. They are not intended as modeling tools for the quantification of the effect of stress on these materials. As such, WLR tests must provide a repeatable stress, independent of normal process variation. The results of these tests will be a measurement of the “rate of degradation” of the basic circuit elements caused by a standard stress.     

Design and experimental study on FBG hoop-strain sensor in pipeline monitoring

Pipeline monitoring is an important task for the economic and safe operation of pipelines as well as for loss prevention and environmental protection. The circumferential strain is of significance in pipeline integrity monitoring. In this paper, an indirect pipeline corrosion monitoring method based on the circumferential strain measurement is firstly proposed, with main objectives at designing a circumferential strain measuring device. Combined with unique advantages of optical fiber sensing, an FBG hoop-strain sensor was designed and encapsulated. Its enhanced sensitivity mechanism in the circumferential strain measurement and manufacturing technique is detailed. The experimental study of the developed FBG hoop-strain sensor is conducted on a PVC model pipeline to investigate its characteristics, including reliability and some tentative dynamic tests. Results of model tests show that the FBG hoop-strain sensor demonstrates good performance in the circumferential strain measurement, and can be considered as a practical device for pipeline health monitoring.     

CCD双目立体视觉测量系统的理论研究

利用几何成像原理建立起CCD双目立体视觉测量系统的数学模型,从提高系统测量精度出发,在理论上重点对系统结构参数、图像识别误差与系统测量精度的关系进行了深入的分析和探讨,并通过实验对结论进行了验证.研究内容对实际建立该测量系统具有很强的指导作用.     

Near-field qualification methodology

A methodology that is a combination of analysis, computer simulation, component certification, self-tests, and comparison tests is presented for the accuracy qualification of near-field antenna measurement ranges. The analysis uses closed-form equations to establish upper-bound far-field determination errors due to near-field measurement errors. Computer simulation is used to model the specific near-field measurement errors associated with the near-field measurement system components. The closed-form equations and computer simulations are used to form a near-field error budget for each of the near-field measurement system components. A near-field system component certification is undertaken to measure the near-field measurement system component error and establish that they are within the error budget     

A built-in performance-monitoring/fault isolation and correction(PM/FIC) system for active phased-array antennas

A built-in performance-monitoring/fault isolation and correction (PM/FIC) system for an active phased-array antenna has been developed and tested. This PM/FIC system employs a transmission line signal injector embedded at the radiating aperture together with a phase-toggling technique for signal detection. Hardware components for a demonstration test-array have been developed, fabricated, and assembled. Eight active elements are fed by four dual-channel transmit/receive (T/R) modules in a column array. Far-field range tests and fault correction tests have also been performed to demonstrate the PM/FIC functions on this test array. Good results have been obtained from these tests. The measurement accuracy of the phase-toggling method is compared with an HP8510 measurement system     

半导体激光器线宽展宽因数的测量

光反馈自混合干涉技术是一种新出现的有别于传统双光束干涉的测试技术.文章基于此技术对半导体激光器进行线宽展宽因数的测量,以激光器HL7851G为对象进行了大量的实验,实验结果与线宽测量法基本一致,相对误差只有3.22%.相比线宽测量法,光反馈自混合法具有成本低、精度高的优点,是一种更加简洁有效的测量方法.