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1.
王勇 《飞机设计》2013,(6):56-59
余度技术是系统或设备获得高可靠性的设计方法之一。为了显著提高系统的任务可靠性,当系统发生故障时,余度系统能够自动完成系统重构,继续正常工作,从而提高了飞机的任务可靠性和安全性。本文从余度设计的概念出发,通过对余度等级、结构、数目及层次等几个方面对余度设计进行分析,结合某大屏幕显示器余度设计,给出了余度设计的基本方法,提出了一种余度管理方案,该设计思想也可用于其它机载设备中。  相似文献   

2.
波音777飞机高升力控制系统余度管理分析   总被引:1,自引:0,他引:1       下载免费PDF全文
飞行控制系统普遍采用余度技术来提高自身的任务可靠性。余度部件效能的发挥程度主要取决于余度管理策略和方法。根据波音777飞机高升力控制系统的基本构架,通过在线监控与信号表决相结合的方法对系统余度管理方法进行研究。在余度管理方法的设计过程中,充分考虑了布线技术、硬件设计技术及与软件相结合的方法,不但简化了襟缝翼控制器的硬件设计,同时也简化了控制器软件的设计难度,提高了系统可靠性,所用到的方法对同类系统设计有一定的参考价值。  相似文献   

3.
Safe, reliable, and low cost space-based navigation is being provided with embedded INS/GPS systems such as the space integrated GPS/INS (SIGI). The SIGI is being used for various space vehicle applications such as launch vehicles, orbital vehicles, and re-entry vehicles. This paper describes current space vehicle navigation capabilities. The SIGI is being enhanced to provide additions to these existing capabilities with such items as higher processing and a commercial-off-the-shelf operating system. This will allow hosting of various software applications such as advanced navigation functions, flight control, guidance and vehicle management algorithms. The SIGI can host redundancy management functions by incorporating a cross channel data link card (CCDL) using a high speed firewire bus. The SIGI can then be used as a redundancy management platform which has application to current space vehicle avionics topologies incorporating distributed processing architectures  相似文献   

4.
The Dawn science operations team has designed the Vesta mission within the constraints of a low-cost Discovery mission, and will apply the same methodology to the Ceres mission. The design employs proactive mapping mission strategies and tactics such as functional redundancy, adaptability to trajectory uncertainties, and easy sequence updates to deliver reliable and robust sequences. Planning tools include the Science Opportunity Analyzer and other multi-mission tools, and the Science time-ordered listings. Science operations are conducted jointly by the Science Operations Support Team at the Jet Propulsion Laboratory (JPL) and the Dawn Science Center at the University of California, Los Angeles (UCLA). The UCLA Dawn Science Center has primary responsibility for data archiving while the JPL team has primary responsibility for spacecraft and instrument operations. Constraints and uncertainties in the planning and sequencing environment are described, and then details of the science plan are presented for each mission sub-phase. The plans indicate that Dawn has a high probability of meeting its science objectives and requirements within the imposed constraints.  相似文献   

5.
电传飞行控制系统的余度设计技术   总被引:3,自引:0,他引:3  
余度设计是提高电传飞行控制系统安全性与任务可靠性的一种重要手段。对电传飞行控制系统中的余度设计内容进行了介绍,探讨了这一领域的一些重要问题。主要内容包括相似余度,非相似余度,解析余度,功能冗余设计技术。对其核心技术和研究难点进行了分析,为进一步研究打下了基础。  相似文献   

6.
Failure detection and redundancy management is discussed for avionics applications of integrated navigation involving coordinated use of multiple simultaneous sensor subsystems such as GPS, JTIDS, TACAN, VOR/DME, ILS, an inertial navigation system (INS), and possibly even Doppler AHRS. A brief high level survey is provided to assess the status of those techniques and methodologies advertized as already available for handling the challenging real-time failure detection, redundancy management, and Kalman filtering aspects of these systems with differing availabilities, differing reliabilities, differing accuracies, and differing information content/sampling rates. Following the status review, a new failure detection/redundancy management approach is developed based on voter/monitoring at both the raw data and at the filtered-data level, as well as using additional inputs from hardware built-in-testing (BIT) and from specialized tests for subsequent failure isolation in the case of ambiguous indications. The technique developed involves use of Gaussian confidence regions to reasonably account for the inherent differences in accuracy between the various sensor subsystems. Online estimates of covariances from the Kalman filter are to be used for this purpose (when available). A technique is provided for quantitatively evaluating both the probability of detecting failed component subsystems and the probability of false alarm to be incurred, which is then to be traded off as the basis for rational selection of the thresholds used in the automated decision process. Moreover, the redundancy management procedure is demonstrated to be amenable to pilot or navigation operator prompting and override, if necessary.  相似文献   

7.
所设计的控制器由3个完全相同的控制通道构成,每个控制通道的硬件系统由2片TI公司的TMS320F2812DSP及其外围电路组成,其中的1片主要用于控制律计算、控制量输出,同时兼顾部分数据采集,另1片用于余度数据管理、数据采集以及部分控制量输出;软件系统是在TI公司的集成开发环境CCS2.1平台上用C 代码编写的。2套DSP软件程序由时序逻辑及任务调度、数据采集、通信、余度数据管理、控制律计算、结果输出和过程数据保存等模块,经优化组合而成。该系统较单冗余和双冗余系统具有更高的可靠性。  相似文献   

8.
无人机飞行控制与管理   总被引:2,自引:0,他引:2  
从无人机工程研制的角度出发,介绍了工程中常用的无人机飞行控制与管理系统的组成、结构、功能与外部接口;分析了系统功能设计时在飞行控制、飞行任务管理与规划、机载设备故障判断与处理、遥控遥测管理以及任务设备管理等方面应考虑的主要问题;从系统控制权限逐步增大的角度论述了无人机典型的遥控控制、人工干预自动控制以及自主控制等控制方式的特点、适用情形和发展前景;讨论了系统研制过程中的控制律设计、控制与管理策略设计、软件开发和高逼真仿真试验等主要关键技术;最后,归纳了区别于有人机系统的显著特点以及通用化、综合化、智能化和网络化的发展趋势。  相似文献   

9.
The electrical power systems of orbiting unmanned spacecraft generally consist of energy-conversion devices in combination with energy-storage and conditioning components. The development of efficient pulse-duration modulation regulators suggests configurations smaller, lighter, and cheaper than conventional dissipative voltage regulators. These savings may or may not be realizable, depending upon the system reliability design goal and amount of redundancy required to meet the goal. Three spacecraft electrical power systems, each containing a solar-cell energy converter and using different voltage regulation schemes, are compared for a common mission specification. Each system is made to meet a given reliability goal by a technique that adds redundant components in a manner that minimizes a system design characteristic such as weight. The reliability design goal is kept constant as mission length is increased, permitting system comparison in terms of weight and cost as a function of time.  相似文献   

10.
对于大型飞机来说,飞行控制系统各部件(包括传感器)多采用高余度的硬件配置来提高系统的任务可靠性,但对小型飞机来说,由于受重量、空间及费用等原因的影响,一些传感器不适合安装三余度或四余度传感器。对于二余度或单传感器来说,如何鉴别故障传感器或判断传感器是否发生故障较为困难。同样,传统的故障诊断与隔离方法并不能隔离三余度传感器系统中的多个故障。为了解决低冗余度传感器故障诊断问题,提出一种不依赖数学模型的奇偶方程方法与小波分析相结合的传感器故障诊断方法。  相似文献   

11.
The question of Traveling Wave Tube (TWT) reliability in space poses some unique problems. First, since tube reliability has a tremendous impact on system design and overall cost, if problems do occur, they are highly visible. Second, attaining high reliability is made difficult by small production runs and short delivery schedules. Finally, the now-common 10 year life specification is combined with state-of-the-art performance requirements, forcing design changes and adding risk. To meet these requirements, we emphasize certain design and manufacturing ground rules. When orbital TWT problems do occur, our experience is that they are usually caused by infant mortality, not wearout. Data based on operation in space show that with close attention to the details of design and manufacturing, reliability exceeding the 500,000 hours MTBF normally specified is achieved. Traveling Wave Tube reliability and overall performance have a tremendous impact on system design and the overall cost of a satellite. TWT reliability determines the amount of redundancy needed to meet a given satellite mission objective. Increased redundancy means increased complexity and weight of the spacecraft. The TWTs, with their Electronic Power Conditioners, also dissipate over 80% of all spacecraft power. Increased tube efficiency will therefore simplify matters all around. Because of the critical impact of tubes, if technical problems do occur, they are highly visible at the system level, where rumors of failure spread like wildfire in the fairly small space community. Attaining high reliability is difficult because of the many conflicting requirements.  相似文献   

12.
介绍双发(Twin-engines)系统的战斗机的机载供电系统控制器的设计和实现。机载供电系统控制器是管理飞机的供电系统的航空电子设备,是飞机供电系统的核心设备,肩负飞机安全的使命。为了提高控制器的可靠性和灵活性,放弃传统的模拟方法,使用先进的数字化技术实现对飞机供电、配电系统的管理。在设计中为了提高可靠性,使用主动复制的容错技术,设计了双余度控制器,在发生单通道错误的情况下,整个系统能够正确工作。对机载供电系统控制器容错技术进行了研究,包括双余度系统的管理策略、同步控制机制、余度管理和故障综合、信号比较监控和通道切换逻辑。  相似文献   

13.
The New Horizons Spacecraft   总被引:1,自引:0,他引:1  
The New Horizons spacecraft was launched on 19 January 2006. The spacecraft was designed to provide a platform for seven instruments designated by the science team to collect and return data from Pluto in 2015. The design meets the requirements established by the National Aeronautics and Space Administration (NASA) Announcement of Opportunity AO-OSS-01. The design drew on heritage from previous missions developed at The Johns Hopkins University Applied Physics Laboratory (APL) and other missions such as Ulysses. The trajectory design imposed constraints on mass and structural strength to meet the high launch acceleration consistent with meeting the AO requirement of returning data prior to the year 2020. The spacecraft subsystems were designed to meet tight resource allocations (mass and power) yet provide the necessary control and data handling finesse to support data collection and return when the one-way light time during the Pluto fly-by is 4.5 hours. Missions to the outer regions of the solar system (where the solar irradiance is 1/1000 of the level near the Earth) require a radioisotope thermoelectric generator (RTG) to supply electrical power. One RTG was available for use by New Horizons. To accommodate this constraint, the spacecraft electronics were designed to operate on approximately 200 W. The travel time to Pluto put additional demands on system reliability. Only after a flight time of approximately 10 years would the desired data be collected and returned to Earth. This represents the longest flight duration prior to the return of primary science data for any mission by NASA. The spacecraft system architecture provides sufficient redundancy to meet this requirement with a probability of mission success of greater than 0.85. The spacecraft is now on its way to Pluto, with an arrival date of 14 July 2015. Initial in-flight tests have verified that the spacecraft will meet the design requirements.  相似文献   

14.
针对传统星载数据管理系统应用层与数据访问层耦合度高,应用软件进行设备访问时须了解底层硬件细节、软件复用率低等问题,研究了CCSDS(Consultative Committee for Space Data Systems,空间数据系统咨询委员会)制定的CDAS(Command and Data Acquisition Service,命令与数据获取业务)的功能、特点及其工作原理,结合新一代综合电子系统的硬件模块功能特点,深入分析了如何在综合电子系统中实现CDAS.CDAS已在某预研课题综合电子样机中应用,测试试验表明,CDAS应用于综合电子系统可以为上层应用提供便捷的设备访问服务,为综合电子系统实现任务规划等复杂功能提供有力的技术保障.  相似文献   

15.
The advanced avionics and flight controls group of advanced airlift and tanker systems is dedicated to integrating, prototyping, demonstrating, evaluating and testing advanced state-of-the-art technologies Vv that are candidates for future aircraft use (for new and in-service aircraft), or that are solutions to old or new/upcoming requirements and needs. The group's mission is to transition the applicable technologies into Boeing platforms. One of the research areas investigated is that of Enhanced Vision Systems (EVS)  相似文献   

16.
航电系统作为飞机的"大脑"和"神经中枢",主要完成与飞行任务相关的功能,在机载系统中占有重要地位。探讨了航电系统从分离式结构到联合式结构再到现在普遍应用的IMA结构的发展历程;分析了分布式航电系统发展到现今阶段所应用的关键技术,如维护技术、网络、操作系统、中间件、系统开发方法及支撑工具等;展望了分布式航电系统的发展趋势:它将会进一步提高综合化程度,引入人工智能、模式识别及传感器系统综合等高端技术,向着跨平台、智能化、网络化的方向发展。  相似文献   

17.
现代战争中,军用飞机需要与外界进行广泛的信息交换,实时的全面掌握战场态势,保证有效完成作战任务。面对日益复杂的作战态势,飞行员难以承担如此繁重的人工管理和决策,由此产生了战术任务飞行管理系统。文章从介绍战术飞行管理技术的发展开始,闸释了战术飞行管理与任务规划系统综合发展的必然趋势,分析了军用飞机战术任务飞行管理系统的功...  相似文献   

18.
Functional partitioning, redundancy structure, internal communications, and software modularization define the architecture of a digital automatic flight control system (DAFCS). Selection of a suitable system architecture for commercial transports involves such factors as the functional scope, growth provision and flexibility requirements, sensor interfaces, the aircraft's actuator and control surface redundancy, and the dispatch reliability requirements. Trade-offs concerning these various factors are discussed, and it is shown that a very versatile and almost universal DAFCS can be configured to meet the general and peculiar needs associated with each aircraft application. Specific results associated with this system's recent demonstration flights in the DC-10 aircraft, as well as examples from several other transport aircraft applications of the same DAFCS architecture, are used to illustrate the design concepts.  相似文献   

19.
k/N(G)结构系统初始备件配置方法   总被引:3,自引:0,他引:3  
卢雷  杨江平 《航空学报》2014,35(3):773-779
针对现有备件冗余度建模中无限呼叫总体假设不合理、供应可用度计算困难的问题,提出一种k/N(G)结构系统初始备件配置方法。首先,采用有限源排队论获取备件短缺数概率分布。然后,给出计算k/N(G)结构系统供应可用度的方案,并证明了方案的正确性。该方案在计算随机挑选的一套系统未因备件短缺而停机的概率基础上,利用k(或更多)套系统良好的二项分布概率估计系统供应可用度。最后,应用边际分析算法确定各项备件的数量。实例分析表明:该方法能优化k/N(G)结构系统各组成部件的库存数量,且与单项法相比具有明显的优势,能以较少的备件费用达到相同的供应可用度目标。  相似文献   

20.
根据气球载电子系统的特点和任务需要,改变传统的以平均故障间隔时间为中心的设计思想,介绍了一种基于无维修使用期的可靠性设计思想。这种设计思想强调故障的可预计性和可靠性水平的可保证性,强调高标准,从根本上提高产品固有可靠性水平。探讨了冗余设计、引人容错设计、可重构性设计、动态设计、故障软化设计、环境防护设计和降级设计等各种可靠性设计技术和方法。  相似文献   

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