捷联惯测组合快速标定方法

结合现行捷联惯测组合标定时间长、操作复杂的实际,针对目前几种捷联惯测组合快速标定方法中存在的问题,提出了一种“12位置+速率”标定的快速标定方法.在粗调平免对北的条件下,将速率标定与位置标定结合进行,大大缩短了标定时间.进行了更为合理的位置编排,使得标定结果精度更接近精确调平对北条件下的标定结果.进行了误差系数分离的推...     

激光陀螺捷联惯性导航系统的误差系数标定研究

惯性器件标定一般都必须对北和调平,以消除地速及重力加速度的影响,但是不适合在靶场及其他野外环境下采用.根据激光捷联惯导系统的误差方程,在激光捷联惯性组合不指北、不调平情况下,通过十位置的标定方法,抵消掉地速及重力加速度的影响,从而得出加速度计的误差系数和陀螺的零偏.最后对实验精度进行了论证,认为此方法可以满足激光陀螺捷联系统的性能要求.本方案利用最少的测试位置,得到了所有需要的信息,利用率高.     

一种惯性测量组合的静态标定方法研究

某些情况下,在惯性测量组合的标定与对准过程中,转台的调平及寻北精度不能满足要求,大大降低了标定和对准的精度.为了弥补上述不足,文中提出了六位置标定方案.利用六位置方案对惯性仪器主要误差项进行标定,并进行了误差补偿的研究.通过仿真及误差分析,证明这种标定方案可以满足高精度、实时性的要求.     

汽车排放气体定容采样测试CFV-CVS系统的研究

随着国家对汽车发动机排放污染物的治理和排放法规的建立健全，排放测试工作日趋重要起来．本文着重对排放测试分析系统中的定容采样（CVS）装置进行了研究．介绍了CVS中的关键部件临界流量文氏管（CFV），讨论了它的设计原理和计算过程，以及精度标定等，并简要叙述了CVS中的其它部件的作用．     

含CL-20的改性双基推进剂燃速数值模拟

借助六硝基六氮杂异伍兹烷（CL-20）的热分解特性，确定了CL-20的化学结构参数；通过分析含CL-20的改性双基（CL-20-CMDB）推进剂的燃烧特性，改进了一维气相反应流燃速模型，进而模拟了CL一20-CMDB推进剂的燃速。数值模拟结果显示，理论计算结果与实测值吻合的很好；随CL-20含量增加，可提高非催化CL-20一CMDB推进剂的燃速，但效果并不显著。     

高精度捷联惯导系统的系统级标定方法

针对现有的标定技术存在较大误差、且误差随着位置偏离的增加而增加的问题,提出一种迭代求解的方法。基于高精度捷联惯导系统的一般输出模型,推导出误差模型,通过简单的位置编排,激发出导航速度误差,反推出误差参数,并不断修正输出模型参数,使导航误差不断减小,达到高精度捷联惯导系统标定目的。分析结果证明：该方法标定精度高、方法简单,无需精确的寻平和寻北,能够满足导航需要,具有较高的工程实用价值。     

惯性组合误差射前标定方法研究

文中讨论了利用导弹起竖过程,合理选择标定位置和标定参数对惯性组合射前标定的方案.该方案兼顾了射击精度和快速性要求,解决了惯性组合射前标定的难题,可应用于实际导弹发射.     

导弹测试设备故障模式分析与诊断技术

为实现导弹地面测试系统的故障诊断,依据系统的内部特点,按操作流程抽取电路子网络,研究了采用逆向推理的方法进行子系统电路的故障模式分析.考虑到抽取出来的电路子网络是较简单的开关/继电器组合,故采用采样点来表征电路信息,这样就可以利用状态点的信息组合来进行故障的检测和诊断.最后,通过实例验证了这一方法的实用性和有效性,为类似复杂电子系统故障诊断的实现提供了新的方向.     

ー种快速高精度自主式寻北仪设计及精度分析

自主定向是大型光电跟踪设备和惯性导航设备的关键技术。为了降低成本并适应快速高精度自主寻北定向的需要，深入研究了基于哥氏效应的加速度计寻北（也称为非陀螺寻北）系统。根据加速度计寻北仪的工作原理，结合工程实际，设计了一套铅垂轴系单轴速率的寻北系统。针对系统结构组成，从加速度计、光电编码器的选择及转台、数据处理等的设计出发，讨论了该方案的结构实现。根据加速度计寻北原理的数学模型，详细分析了影响寻北精度的转速误差、偏时误差、测角误差、采样误差等关键因素，并按照样机的实际参数进行了误差计算，计算出寻北标准差为88”，     

硝酸铵／铝／高氯酸铵系复合推进剂的点火特性

采用在端羟基聚丁二烯（ＨＴＰＢ）２０％（质量比）中加入铝粉２０％（质量比），再加入氧化剂ＡＮ（硝酸铵）／ＡＰ（高氯酸铵）合计６０％（质量比）的推进剂，取得了在ＡＮ中加入ＡＰ时的燃速特性和点火特性。在燃烧压力为１ＭＰａ时，ＡＮ系复合推进剂的燃速为１．２ｍｍ／ｓ，ＡＰ系复合推进剂的燃速为４．０ｍｍ／ｓ。在压力１ＭＰａ、照射能量６００Ｗ的条件下，ＡＮ系复合推进剂的点火滞后时间约为４６０ｍｓ，ＡＰ系复合推进剂的点火滞后时间仅为７．５ｍｓ。ＡＮ系复合推进剂点火滞后时间长的主要原因是化学点火滞后时间长。在ＡＮ系复合推进剂中混入ＡＰ时，燃速同样增加，点火滞后时间随着燃速的增加而减少。     

Stability of the Third Generation Intensifier under Illumination

The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.     

Passive Acoustic Radar for Detecting Supersonic Cruise Missile

A Passive Acoustic Radar is presented as a necessary complement to electromagnetic wave radar, which will be expected to be an effective means for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles with diverse shapes are expounded via experiment. It is pointed out that simulation experiment could be implemented using bullet or shell instead of cruise missile. Based on theoretical analysis and experiment, the ““acoustic fingerprint““ character of cruise missile is illustrated to identify it in a strong noise environment. After establishing a locating mathematical model, the technique of acoustic embattling is utilized to resolve a problem of confirming the time of early-warning, considering the fact that velocity of sound is much slower than that of light. Thereby, a whole system of passive acoustic radar for detecting supersonic cruise missile is formed.     

Design and Analysis of Test Schemes of Static Postponing Time on Shrapnels Used to Riot Control

The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures,the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done,feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.     

Super-resolution Restoration of Remote-sensing Images

A novel image restoration scheme, which is super-resolution image restoration algorithm Poisson-maximum-afterword-probability based on Markvo constraint （MPMAP） combined with evaluating image detail parameter D, has been proposed. The advantage of super-resolution algorithm MPMAP incorporated with parameter D lies in the fact that superresolution algorithm MPMAP model is discrete, which is in accordance with remote-sensing imaging model, and the algorithm MPMAP is proved applicable to linear and non-linear imaging models with a unique solution when noise is not severe. According to simulation experiments for practical images, super-resolution algorithm MPMAP can retain image details better than most of traditional restoration methods; at the same time, the proposed parameter D can help to identify real point spread function （PSF） value of degradation process. Processing result of practical remote-sensing images by MPMAP combined with parameter D are given, it illustrates that MPMAP restoration scheme combined PSF estimation has a better restoration result than that of Photoshop processing, based on the same original images. It is proved that the proposed scheme is helpful to offset the lack of resolution of the original remote-sensing images and has its extensive application foreground.     

Design and Simulation of TF and TA Controller for Missile

A nonlinear terrain following(TF) and terrain avoidance(TA) controller is proposed for missile control systems. Based on classical TF algorithm (adaptive angle method), a new method for TF controller is proposed by using angle of attack. A method of obtaining terrain outline data from digital elevation map (DEM) for TF control is discussed in order to save store space. A TA algorithm is proposed by using bank-to-turn technique. The block control model, which is suitable for backstepping design, is given for nonlinear model of missile. Making full use of the characteristics of the system and combining block control principle and backstepping technique, a robust controller design method is proposed. Uncertainties in every sub-block are allowed, and can be canceled by using the idea of nonlinear damping. It is proved that the state tracking errors are converged to a neighborhood of the origin exponentially. Finally, nonlinear six-degree-of-freedom simulation results for the missile model are presented to demonstrate the effectiveness of the proposed control law.     

Design of Non-fragile Satisfactory Estimator for Linear Continuous Perturbed Stochastic Systems

The design problem of non-fragile estimator is addressed for a class of perturbed linear continuous systems. The perturbations occur on the plant and estimator parameters. The estimator designed should force the error system to achieve the desired decay rate and force the steady error variance less than the specified upper bound irrdevancy of the admissible plant perturbations and estimator perturbations. Consistency problem of the decay rate with the variance upper bound is first considered via linear matrix inequality （LMI） approach. The solution of the estimator parameter under specifications to be consistent is then discussed. The consistency condition of specifications and estimator parameter solution are transformed to feasible or minimum problems subject to a set of LMI respectively. The method is illustrated by a numerical example.     

An Improved Scene-based Nonuniformity Correction Algorithm for Infrared Focal Plane Arrays Using Neural Networks

The improved scene-based adaptive nonuniformity correction （NUC） algorithms using a neural network （NNT） approach for infrared image sequences are presented and analyzed. The retlna-like neural networks using steepest descent model was the first proposed infrared focal plane arrays （IRFPA） nonuniformity compensation method, which can perform parameter estimation of the sensors over time on a frame by frame basis. To increase the strength and the robustness of the NNT algorithm and to avoid the presence of ghosting artifacts, some optimization techniques, including momentum term, regularization factor and adaptive learning rate, were executed in the parameter learning process. In this paper, the local median filtering result of Xij （ n ） is proposed as an alternative value of desired network output of neuron Xij （ n ）, denoted as Tij （ n ）, which is the local spatial average of Xij （ n ） in traditional NNT methods. Noticeably, the NUC algorithm is inter-frame adaptive in nature and does not rely on any statistical assumptions on the scene data in the image sequence. Applications of this algorithm to the simulated video sequences and real infrared data taken with PV320 show that the correction results of image sequence are better than that of using original NNT approach, especially for the short-time image sequences （several hundred frames） subjected to the dense impulse noises with a number of dead or saturated pixels.     

Piecewise Filter of Infrared Image Based on Moment Theory

The disadvantages of IR images mostly include high noise, blurry edge and so on. The characteristics make the existent smoothing methods ineffective in preserving edge, To solve this problem, a piecewise moment filter （PMF） is put forward. By using moment and piecewise linear theory, the filter can preserve edge. Based on the statistical model of random noise, a related-coefficient method is presented to estimate the variance of noise. The edge region and model are then detected by the estimated variance. The expectation of first-order derivatives is used in getting the reliable offset of edge. At last, a fast moment filter of double-stair edge model is used to gain the piecewise smoothing results and reduce the calculation. The experimental result shows that the new method has a better capability than other methods in suppressing noise and preserving edge.     

Bistatic Sonar Localization Based on Best Linear Unbiased Estimation

A best linear unbiased estimation （BLUE） algorithm for bistatic sonar localization is proposed. The Cramer-Rao bound for bistatic Sonar and the geometrical dilution of precision （GDOP） in different conditions are given. The simulation results show that the location accuracy of BLUE algorithm is higher than the weighted least square method.     

Research on Gear-broken Fault Diagnosis in a Tank Gearbox

A fault diagnosis method of working position gear in a tank gearbox is put forward based on simulating the fault of working position gear in an actual tank, extracting the envelope of vibration signal by Hilbert transformation amplitude demodulation method, and zooming the low-frequency band to envelope signal.