感知"角秒"——ERA 4000系列角度编码器

高效的驱动系统需要精确的位置信息.一种特殊的光栅鼓栅线制造工艺和独特的扫描原理使海德汉新系列的角度编码器具有很高的精度.     

高精度导弹射程精确计算方法

针对靶场导弹射程精确计算存在的问题,提出了利用微积分算法改进导弹射程的精确计算,具体采用曲线积分的方法,详细推导了一种不同于传统导弹射程精确计算的新方法,并提供了此方法的具体算法和模型。在理论分析的基础上,采用新方法对算例数据进行计算和分析,结果表明:用新方法计算得到的导弹射程精度达到亚毫米级,且精度与导弹射程大小无关。该方法已在靶场导弹射程的计算中得到成功应用。     

高精度撞击超完美结局"深度撞击"的过程回放

“深度撞击”是人造探测器首次以主动撞击的方式来探测彗星,美国航空航天局已证实,其精度比科学家预计得还要精确,误差还不到1米(事先预计为1千米),因而可以说它代表了空间技术的一次大飞跃,并有望取得天文学的丰硕成果。     

"黄蜂之眼"F/A-18E/F升级光电红外传感器系统

美国海军的 F/A—18E/F 通过装备先进的光电红外传感器吊舱,作战效能得到大幅度提升,除了用先进瞄准前视红外系统(ATFLIR)吊舱提升精确对地攻击能力外,美国海军正在准备装备一种新型的红外搜索与跟踪(IRST)吊舱,以提升其空战能力。     

优先发展的"重中之重"谈国外机载计算机技术的发展现状和策略

21世纪对战斗机的航空电子系统提出了更高的要求,在作战能力方面,它要适应未来网络中心战(NCW)对飞机平台能实施信息战、电子战的要求,即在保护自身不受敌方攻击的同时,飞机要具有随时、随地通过动态组网的高速无线网络获得所需信息和智能化处理信息的能力;在综合保障能力上,它要具有高可靠性、自修复能力和免维修能力;在目标攻击时具有提供超视距多目标攻击和对地/面精确打击的能力;在成本需求方面,则要达到全寿命周期成本"买得起、用得起"的水平.     

深空X频段测速数据误差分析

X频段是深空测控的主用频段,其多普勒测速精度远高于S频段,这一结论在"嫦娥二号"任务X频段深空测控技术试验中得到了验证,测速精度约为1mm/s。针对X频段高精度测速,本文分析了目前采用的径向速度近似计算公式,理论分析其产生的误差在地月转移和环月轨道段可达1cm/s。通过"嫦娥二号"任务X频段测控技术试验,以事后精密轨道为基准进行残差分析,结果表明,相比精确公式,近似公式计算测速数据的残差会增加1mm/s,已与X频段测速精度本身相当,因此,多普勒测速近似计算在X频段测量中已不再适用,应使用本文中列出的精确计算公式。     

精确制导技术发展展望

介绍了精确制导技术的基本类型和基本分类,分析了国外精确制导技术的三项新进展双模寻的制导及其关键技术,光纤制导及其关键技术和近代中制导的INS/GPS制导,对未来精确制导技术的发展提出了四点预测.     

空军精确制导弹药保障模式与发展方向

空军转型发展对精确制导弹药保障提出新需求,必须转变精确制导弹药保障模式,以适应"空天一体,攻防兼备"战略要求。本文主要分析研究精确制导弹药保障能力建设面临的问题,提出解决问题的对策、改革方向,为空军精确制导弹药保障能力建设创新发展提供借鉴和支持。     

"自适应加工"技术--零件快速装夹新概念

"自适应加工"是Delcam集团在近30年的加工和检测经验基础上推出的一个新的零件快速装夹的解决方案.通过"自适应加工"解决方案可以帮助机床操作人员在几分钟内快速准确地进行工件的重复装夹定位,将工件的加工余量与数控加工刀路对齐,而以往则需要几个小时,因而能为机械加工过程节省大量生产成本、缩短重复装夹时间、减少机器空闲时间、提高成品率,大大提升现有的生产力."自适应加工"解决方案是通过OMV和PS-Fixture 2个软件共同配合完成的.OMV是一个运行在加工机床上的可脱机编程、能自动检测具有自由曲面和几何特征的实体的在机检测解决方案;PS-Fixture是"自适应加工"技术的核心软件,通过计算得出零件当前位置坐标系与机床坐标系的偏差量,从而相应调整机床坐标系,来实现一个离线或在线的软件精确装夹的解决方案.     

飞机蒙皮厚度精确加工的最新技术——以数铣替代化铣的绿色加工工艺

分析了飞机蒙皮零件加工传统工艺无法满足精确加工要求和绿色制造发展需要的客观现实.并就正在推广使用的蒙皮精确铣,以及飞机蒙皮厚度加工由化铣向数铣发展的新趋势,作了详细论述.同时,还对国际上最新推出的集蒙皮切边、开口、制孔和蒙皮厚度精确加工于一体的多功能蒙皮精确铣和镜像铣,作了系统介绍.     

Caution, contention, and consolidation

The Washington Watch column provides an overview of NASA's cautious approach to the launch of Space Shuttle Discovery STS-114, contention between the Air Force and administration about production of the F/A-22 Raptor aircraft, and consolidation among U.S. airline companies.     

Automation of Base Record Communications

Results of a study leading to the preparation of a concept formulation package and development plan for automation of record communications on a world-wide basis during the 1970' s are presented. The Automatic Base Communication System (ABCS), centered on an electronic store and forward message switch, utilizes stored programs to handle all U. S. Air Force base record communications.     

The Tactical Communications Satellite

Early in 1969 the U. S. Air Force placed into synchronous orbit the largest communications satellite built to date. This vehicle, the tactical communications satellite (TACSAT), together with a variety of ground terminals, is designed to test experimentally and develop tactical communications concepts for all military services. This paper describes the spacecraft design focusing on the communications repeater. Measured performance characteristics affecting communications utilization of the spacecraft are presented.     

History of Time-Frequency Technology

Present-day collision avoidance systems (CAS) of the time-frequency variety employ modes of operation similar to those of airborne equipment which has been operating in military aircraft since 1959. A fleet operational evaluation of these systems began in 1961 in aircraft of U. S. Navy Helicopter Squadron HS-4, based on the aircraft carrier U.S.S. Yorktown. This equipment utilized a local clock in each aircraft, a separate time slot for each aircraft's interrogation signal, air-to-air coarse synchronization of all stations, and sufficient free-drift stability for time slot keeping. Operational use of one-way ranging with elimination of propagation delay offsets, higher clock stability for open-loop time keeping in the SNS-64 ... AN/APN-169 family of systems began in 1964 in U. S. Air Force C-130E turboprop aircraft. In 1965, use of the EROS I collision avoidance system began during flight testing of F-4 Phantom supersonic aircraft.     

试论教练装备空海军联合发展

阐述了美国空军和海军教练机装备发展现状,分析了美国空军和海军教练机装备联合发展的过程、原因以及优势,并结合我国空军和海军教练机的发展情况,得出我国空/海军教练机装备联合发展的几点启示。     

Definitions of Effectiveness Terms: A Report on the Purpose and Contents of MIL-STD-721B

The impact of the Systems Effectiveness concept upon U.S. military terminology required for acquisition of modern weapon systems necessitated a thorough revision of MIL-STD-721A and consolidation with MIL-STD-778 and MIL-STD447. Inclusion of a number of new terms and their definitions, as well as addition of standard definitions for terms on human factors and safety, was found to be necessary. The resulting military standard has been approved by the U.S. Department of Defense for use by all of its departments and agencies. Its contents should be of great interest to management and engineers in private industry who are concerned with the development and production of weapon systems for the Army, Navy, and Air Force. This standard is now in print and will be available for distribution early in 1967; this paper is written by one of the participants in the revision and compilation of this military standard and is published here for the purpose of information on its scope and contents.     

Near term approach to data relay for satellites under test

The increasing need for a continuous communications link with U.S. Department of Defense (DoD) spacecraft during test missions in low Earth orbit (LEG) has resulted in greater interest in geosynchronous data relay services. This may be a more economical alternative to building additional remote tracking stations for the Air Force Satellite Control Network (AFSCN), and avoids tying up operational assets for a test mission. A low-cost near-term approach for such a space-based data relay system would utilize two existing Defense Satellite Communication System III spacecraft, two existing ground terminals, and a small, standardized terminal using autonomous antenna pointing for the space vehicle under test. Such a system design is presented     

航空兵部队飞行安全评估系统研究与实践

根据航空兵部队飞行安全的特点,基于“人、机、环境“系统工程理论,并结合航空兵部队的实际,开发了一套航空兵部队飞行安全评估系统.该系统具有客观评估安全形势、发现薄弱环节和引导航空兵部队安全行为的功能.最后,给出了对航空兵部队进行飞行安全评估的应用实例.     

Lawmakers battle for reform on many fronts

In Washington, much of the attention of the nation's leaders is focused on the economy, on next year's election, and on the war's aftermath in Iraq. Polls show that a restive nation wants more jobs and fewer casualties in the war on terror. In the world of aerospace, few topics seem to be headline-grabbers lately, but the lawmakers are always working on air and space issues--some of them very familiar to Americans. The U.S. program for manned spaceflight remains controversial and a firm date for a return to flight elusive. The little-known air war in Colombia is receiving more attention than many in Washington would like. And the Air Force plan to lease air-refueling tankers continues to draw flak from the Hill.     

US Air Force EarthRadar for detection and discrimination of buriedunexploded ordnance

The US Air Force EarthRadar system is a multi-purpose sensor designed and constructed using "radar" principles. This technology was originally developed for the US Air Force to detect buried unexploded ordnance (UXO). Bakhtar Associates developed the US Air Force EarthRadar technology under the DoD SBIR program. The system is capable of detecting buried metallic and non-metallic objects, including glass vials. In addition, the manner in which system hardware, signal processing, and the integrated high resolution global positioning system (GPS) are configured makes it ideal for applications such as mapping subsurface geological features, locating cavities and collapse features, and identifying contaminated ground