小型飞翼布局无人机控制律设计与试飞验证

针对无尾飞翼布局的无人机由于取消了水平尾翼和垂直尾翼,导致纵向、横航向的稳定下降,特别是横航向变为静不安定的问题,设计一种小型飞翼布局无人机全流程飞行控制律。以某型飞翼布局飞机的缩比飞机为控制对象,分析该飞机纵向与横航向的气动特性,采用特征结构配置方式,分别对纵向与横航向进行增稳设计。仿真与实际试飞结果表明：该控制律能够很好地跟踪期望的轨迹,并能有效地抑制侧风扰动,具有良好的工程应用价值。     

小型飞翼布局无人机控制律设计与试飞验证

针对无尾飞翼布局的无人机由于取消了水平尾翼和垂直尾翼,导致纵向、横航向的稳定下降,特别是横航向变为静不安定的问题,设计一种小型飞翼布局无人机全流程飞行控制律。以某型飞翼布局飞机的缩比飞机为控制对象,分析该飞机纵向与横航向的气动特性,采用特征结构配置方式,分别对纵向与横航向进行增稳设计。仿真与实际试飞结果表明：该控制律能够很好地跟踪期望的轨迹,并能有有效地抑制侧风扰动,具有良好的工程应用价值。     

某小型低空高速无人机控制律设计与仿真

利用自动控制理论的知识,分析并建立了某小型低空高速无人机飞行控制系统的控制律,并采用飞机小扰动运动方程进行了初步的验证计算。利用飞机系统仿真的方法,采用飞机全量扰动运动方程对该型无人机飞行控制系统的控制律进行了仿真验证,结果表明,文中所设计的该型无人机飞行控制系统的控制律可以实现该无人机安全发射、稳定爬升、高度稳定、姿态稳定、航向稳定的要求,进而可以实现无人机按预定航路的飞行。     

某型无人机飞行动力学仿真软件设计

无人机飞行动力学仿真是无人机飞行控制系统半实物仿真系统的重要组成部分。为了开发一种实用型的无人机飞行动力学仿真软件,考虑无人机飞行动力学仿真的实时性和精度问题,基于四阶龙格-库塔算法,对无人机飞行动力学非线性模型的实时仿真进行研究,设计和开发了无人机飞行动力学实时仿真软件,并成功应用于某型无人机飞行控制系统的半物理仿真试验。试验和测试结果表明：该动力学仿真软件设计合理并满足飞行仿真要求,具有一定的工程应用价值。     

无人机倾斜转弯非线性飞行控制系统设计

研究无人机(UAV)的倾斜转弯(BTT)飞行控制系统的设计方法，解决UAV高机动倾斜转弯飞行时运动强烈耦合、气动特性强非线性和参数非定常性等特性带来的飞行控制系统设计难题。采用线性二次型最优调节规律对UAV非线性运动零动态系统进行增稳调节；运用非线性控制系统中精确反馈线性化方法对UAV非线性系统进行线性化处理；运用滑模变结构控制方法设计了UAV的BTT控制规律，得到由增稳最优调节规律和滑模变结构控制规律构成的UAV的BTT非线性鲁棒飞行控制系统。基于无人机六自由度非线性动力学模型，进行BTT非线性飞行控制系统数字仿真，仿真结果表明：该控制系统即使在扰动条件下也能达到满意的控制品质，控制糸统的鲁棒性和控制精度能满足UAV高机动倾斜转弯飞行时的控制要求。     

风扰动下的飞翼无人机静态投影控制

根据飞翼无人机特殊外形布局、气动性能及控制品质要求,在风扰动存在情况下,针对系统纵向俯仰通道和横侧向滚转通道,设计了基于鲁棒最优理论的静态投影控制器。分析了投影控制方法的一般原理,建立了飞行控制系统的鲁棒伺服模型,应用最优线性二次型调节器（LQR）方法构成鲁棒伺服LQR控制,并以闭环系统为参考系统,通过静态投影法则以输出反馈重构参考系统主体特征结构,避免了LQR方法中部分反馈变量无法精确测量的问题。仿真过程中对比验证了风扰动下常规PID姿态驾驶仪和静态投影方法的控制效果。仿真结果表明,所设计的静态投影控制系统响应速度快,且具有较强的稳定性和抗风扰动能力。     

基于自主切换的无人机航向跟踪设计

基于某型无人机飞行运动模型,研究设计了基于自主切换的无人机航向跟踪控制律。建立了无人机运动的数学模型,设计了飞行控制系统结构,以及纵向、横侧向控制律和自主导航功能模块,实现了无人机的基本飞行控制和自主导航功能。通过仿真验证,该无人机具有比较理想的飞行航线跟踪和飞行航线切换能力,自主导航功能模块达到了预期的设计要求。     

小型无人机三轴飞行仿真转台设计

针对直接在无人机上验证飞行控制系统成本较高,危险性较大,且受场地限制的问题,设计了一种针对小型无人机的三轴飞行仿真转台。介绍三轴转台主要性能指标和转台结构,对伺服控制系统和伺服软件系统2个方面进行分析,编写了设计程序。分析结果表明:该转台具有体积小、成本低、精度高、使用方便等特点,为小型无人机控制系统的研究提供了一个地面半仿真实验的平台。     

采用逆动力学法的无人机跟踪飞行速度控制系统设计

随着无人机的迅速发展,为扩大其使用范围,急需实现无人机自动追随移动目标,自动编队飞行,自动空中加油和自动着陆等。研究提出了无人机跟踪目标的制导控制系统设计方法。通过理论研究和仿真试验确认了所提速度控制系统设计方法的有效性和相对气动误差的鲁棒稳定性等。     

微小型旋翼无人机总体设计与实现

主要讨论了一种微小型旋翼无人机的设计、制造与试飞验证。在研究涵道风扇式与"单旋翼+气动面"布局的微小型旋翼无人机特点的基础上,提出了微小型旋翼无人机总体设计方案。利用计算流体力学软件Fluent完成了该微型无人机气动面的设计;利用微机电系统惯性测量组件以及地面控制系统完成了该无人机的控制系统设计。微小型旋翼无人机完成了系绳试飞和自由试飞。证明了该微型无人机具有自主悬停能力,并且验证了设计方案的正确性和合理性。     

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.     

Method for Measuring Velocity of Warhead Fragments Based on Photoelectric Detection

For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.     

数码电子雷管中影响点火头性能因素分析

阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅（LTNR）的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明：一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。     

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.     

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.     

Design and Implementation of One Missile Visual Simulation System Based on OpenGL

The implementation of a missile＇s visual simulation system is explained that is developed with OpenGL（open graphic library） and the flight path and flight carriage in different stages of the missile are displayed. The establishment problems of the 3D scene are circumstantiated including the construction and redeployment of the model, creation of the virtual scene, setting of the multi-viewports and multi-windows etc. The missile＇s data driver, system flow, the modules and their mutual relations of the missile visual simulation system are discussed. The missile flight simulation results and effect of the scenes are given.     

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.     

Dynamic Encryption Technology in Ad-hoc Networks

A new dynamic encryption application in ad-hoc networks is proposed. The advantages of this method are its being able to use the previous ciphertext as a seed of a new encryption process, rendering the encryption process effective in all communication process by continuous dynamic key generation together with synchronization, and its capability to cut back on system bandages to a greater extent, which is valuable for the ad-hoc circumstance. In addition, the rationality and effectiveness of this novel encryption method have been verified by the test results.