两种H∞滤波在SINS/GPS组合导航系统中的适应性

针对H∞鲁棒滤波实现算法在SINS/GPS组合导航系统中的适应性问题,将中央H∞滤波和次优后置H∞滤波用于开环SINS/GPS组合系统和闭环SINS/GPS组合系统中,进行滤波校正,结果表明:中央H∞滤波适于用在开环SINS/GPS组合系统中,次优后置H∞滤波适于用在闭环SINS/GPS组合系统.该结论可对组合导航系统中滤波算法的选取提供参考.     

基于H∞滤波的RDSS/INS组合导航研究

文中根据H∞鲁棒滤波理论．提出了基于H∞滤波技术的RDSS／SINS位置全组合导航系统，由H∞鲁棒滤波来提高系统的鲁棒性，对提出的全组合系统进行Simulink仿真。仿真结果表明该系统结构简单，状态估计精度高，系统仿真鲁棒性好，便于工程实现。     

基于H∞滤波的GPS/SINS组合导航系统研究

文中在对H∞估计问题进行数学描述的基础上,建立了一种H∞次优滤波算法的迭代方程.通过在GPS/SINS组合导航系统中的实际应用从精度、鲁棒性等指标方面对H∞滤波和Kalman滤波算法进行比较.仿真结果表明,在理想条件下,Kalman滤波方法具有较高的精度.但是,当系统噪声和量测噪声为有色噪声时,H∞滤波算法明显具有良好的鲁棒性能,估计精度也较高,能有效地克服Kalman滤波器存在的局限性.     

基于光纤陀螺的SINS/GPS组合导航系统的设计与实现

文中在自行研制的光纤陀螺的基础上,基于DSP芯片,采用传统的Kalman滤波技术,采用内组合模式,设计并实现了SINS/GPS组合导航系统,通过车载实验与PHINS组合导航系统的比较,验证了自研组合导航系统的导航精度及可靠性.     

SR-CDKF在组合导航直接法滤波中的应用

为了解决SINS/GPS组合导航系统姿态、速度和位置等导航参数的非线性估计问题,提出了一种基于平方根中心差分卡尔曼滤波(SR-CDKF)的直接式滤波估计方法。系统状态方程选取惯导力学编排方程,系统状态向量和观测向量分别选取SINS导航参数和GPS输出参数,构建了SR-CDKF滤波器。该滤波器可以使导航参数动态过程得到直接反映,并使得直接式滤波计算流程得以实现。以MATLAB中areoblk_HL20模块为基础构建了仿真系统并进行了仿真。仿真结果表明,该算法具有较高的滤波精度、良好的滤波收敛性和稳定性,能使非线性模型下SINS/GPS组合导航系统的导航要求得到满足。     

基于H_∞滤波的GPS/SINS组合导航系统研究

文中在对H_∞估计问题进行数学描述的基础上,建立了一种H_∞次优滤波算法的迭代方程。通过在GPS/SINS组合导航系统中的实际应用从精度、鲁棒性等指标方面对H_∞滤波和Kalman滤波算法进行比较。仿真结果表明,在理想条件下,Kalman滤波方法具有较高的精度.但是,当系统噪声和量测噪声为有色噪声时,H_∞滤波算法明显具有良好的鲁棒性能,估计精度也较高,能有效地克服Kalman滤波器存在的局限性。     

基于小波降噪误差方差模型的GPS/SINS组合导航技术

为进一步提高GPS/SINS组合导航系统的精度,对基于小波降噪误差方差模型的GPS/SINS组合导航技术进行研究。根据小波多尺度理论,分析了小波降噪前后信息的误差方差模型间的理论关系,推导出在小波多尺度分析中平滑信号误差的理论方差模型,将该理论模型引入到GPS后,试验分析证明理论分析与试验结果基本一致;然后以该理论模型为基础,提出了基于小波降噪误差方程模型的GPS/SINS组合导航系统并进行了静态试验验证。试验结果表明,该模型能显著地提高组合导航系统各项导航参数的精度。     

压缩传感理论在GPS/SINS组合导航中的应用

GPS/SINS组合导航系统能够实现在高动态和强电干扰的环境下实时、高精度的导航定位,是当今组合导航技术应用的主要方式.由于组合导航系统复杂度的增加,导致存储数据量增加,对高速度、高可靠性存储的依赖也成为不可回避的问题.压缩传感作为信号采集领域的一种新兴技术,打破了奈奎斯特采样定理对采样信号频率的限制,使得能用更少的数据采样点来近乎完美地恢复信号.介绍了压缩传感理论和GPS/SINS组合导航系统,提出将CS理论用于组合导航系统的设想,并用CS理论压缩和恢复Kalman滤波中的协方差矩阵.仿真结果表明了该方法的有效性.     

基于联邦粒子滤波器的多传感器信息融合算法

提出了一种新的SINS/CNS/GPS组合导航观测方程,并给SINS/CNS/GPS组合导航系统设计了一种新的联邦式数据融合结构。使用粒子滤波器对联邦滤波子系统的多源数据进行融合处理,从而摆脱了经典卡尔曼滤波器的限制。仿真结果表明所提算法在SINS/CNS/GPS组合导航系统的信息融合中是有效性的。     

SINS/低成本基地辅助测速组合导航技术研究

借鉴INS/GPS组合导航系统原理,文中提出了SINS/速度组合导航系统方案.在此方案中,利用基地辅助测速测得的速度信息作为导航系统的辅助信息,通过Kalman滤波来修正SINS系统的误差.仿真结 果表明组合系统导航精度基本达到目前实际应用的水平.应用此方案,只须利用能够提供速度信息的低成本基地辅助测速系统(空基如高空气球等空中平台,陆基如雷达站等)就能实现导航定位的功能,具有实际应用前景和深远意义.     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.     

Overview of Anti-tank Mines

First the different anti-tank mines laying possibilities are shortly summarized： hand emplaced, with mine layers, ground or helicopter relatively topographical well defined, and with cluster systems of projectiles, rockets and aircraft dispensers. Then examples of the three generations of anti-tank mines are presented：Ⅰ generation： detonating only beneath the track; Ⅱ generation： detonating beneath the track and belly; Ⅲ generation： mines with off-route actions. Weight and cost comparisons are strongly favoring the off-route Ⅲ-generation mines.