基于飞行器图像的目标跟踪方法研究

提出了一种利用飞行器图像进行目标跟踪的方法，建立了飞行器图像跟踪系统。该系统利用一种云台控制算法搜索飞行器的图像，通过对飞行器图像的边缘检测、图像中心点提取等处理，实现了飞行器图像定位。理论计算和实际应用表明，该系统可以对低马赫数和高马赫数飞行器进行图像跟踪。     

天文望远镜测角系统的精度检测

通过对１．２ｍ红外望远镜和等高仪的圆感应同步器及整机测角系统检测，提出４．３ｍ望远镜的检则方案。     

The infrared space observatory

The Infrared Space Observatory (ISO), a programme of the European Space Agency, is an astronomical satellite operating at wavelength from 2.5 to 200 m. It will be launched in 1995.The ISO optical subsystem is a cryogenically cooled telescope with its baffling system (main baffle and sunshade). The telescope, a 60 cm Ritchey-Chrétien type, focuses the beam to the four scientific instruments located in its focal plane. The extremely low temperature, 1.8 K, is provided by the payload module (PLM) cryostat, filled with superfluid He.This paper presents the main choices done for the telescope design together with their rationale and the performances achieved on the flight model (FM) of the telescope. The FM telescope is presently installed inside the payload module, ready for the system final verifications.     

The effect of realistic surface properties on low temperature space observatories

We highlight the effect on space-telescope temperatures of thedirectionality of the radiative properties of materials, by showing results from a Monte-Carlo simulation of telescope cooling. The need for further measurements of directional properties is stressed.     

The near infrared high resolution imaging camera program of Beijing Observatory

This paper introduces the program of an adaptive optics system using an infrared camera for the near infrared observations based on the 2.16 m telescope of Beijing Observatory. This system consists of 3 parts: (1), the 2.16 m telescope; (2), the adaptive optics system that will be mounted at the coudé focus on an optical table. It will be used to remove the effect of atmospheric turbulence on the imaging observations; (3), the infrared camera with a 512×512 PtSi IR detector array.     

Orbits for radiatively cooled space telescopes

This paper first outlines the assumed mission requirements for a radiatively cooled space telescope such as EDISON. A summary of relevant characteristics (payload, operating orbit, launcher, lifetime, etc.) for current and proposed cooled telescope missions is then given. This summary includes cryogenic and radiatively cooled missions since in both cases the reduction of heat input to the telescope aperture is a dominant factor in the orbit choice. These missions span the entire range of possibilities from low earth circular, through higher elliptical and circular orbits out to deep space locations such as the Sun-Earth (S-E) libration points and the lunar surface.A full listing of the factors affecting mission selection is then given. The most important points are illustrated by reference to the orbits chosen for ISO, FIRST and SIRTF and those recommended in recent studies of EDISON. Launcher capabilities for direct insertion and the onboard propellant for large velocity changes associated with orbit raising are major constraints in achieving the large payload mass to high orbit which EDISON mission requires. Although it is fairly demanding in launch/boost energy, an orbit about the L2 S-E libration point offers important advantages for a radiatively cooled infrared telescope. Further studies of this orbit and the associated aspects of service module and payload design for the L2 location of EDISON are recommended.     

某新型飞机维修模拟训练系统

介绍了某新型飞机维修模拟训练系统的设计思路以及系统组成和特点,并结合系统的实现讨论了模拟仿真技术应用于装备维修的现实意义.实践证明,应用该系统开展飞机维修模拟训练解决了部队由于维修保障训练设备缺乏,机务人员难以进行全专业综合保障维修训练的难题,大大缩短了新机维修保障训练周期,节约了大量的装备维修保障经费.     

用差分法处理相关性测量数据方法探讨

当测量参数（或称测量元素）具有强相关性时,运用测量求差法解算测量结果,能消除相关性误差因素的影响,获得高精度测量结果,如电影望远镜同帧画幅测量脱靶量.基于此,运用测量方法和数学手段构建一个虚拟的元素相关测量系统,以消除相关性误差因素的影响,同样能获得理想结果.用多台测速雷达组成的系统,可使火炮弹丸空间坐标的测量精度达到毫米量级,从而满足多种火炮立靶密集度的测量精度要求.     

Instrumentation for balloon and rocket experiments

A number of plasma, particle and field detectors used on rocket investigations in and above the Earth's atmosphere are described. Emphasis is on magnetospheric and solar-interplanetary studies. A balloon-borne X-ray telescope system with 20 pointing accuracy is discussed. A PCM telemetry system used on both balloons and rockets to handle scientific data is described including a simple Doppler ranging system that gives location to 1.5 km. A system to reduce and analyze PCM data on the ground is discussed.     

Numerical simulation of a cabin ventilation subsystem in a space station oriented real-time system

An environment control and life support system(ECLSS) is an important system in a space station. The ECLSS is a typical complex system, and the real-time simulation technology can help to accelerate its research process by using distributed hardware in a loop simulation system. An implicit fixed time step numerical integration method is recommended for a real-time simulation system with time-varying parameters. However, its computational efficiency is too low to satisfy the real-time data interaction, especially for the complex ECLSS system running on a PC cluster. The instability problem of an explicit method strongly limits its application in the ECLSS real-time simulation although it has a high computational efficiency. This paper proposes an improved numerical simulation method to overcome the instability problem based on the explicit Euler method. A temperature and humidity control subsystem(THCS) is firstly established, and its numerical stability is analyzed by using the eigenvalue estimation theory. Furthermore, an adaptive operator is proposed to avoid the potential instability problem. The stability and accuracy of the proposed method are investigated carefully. Simulation results show that this proposed method can provide a good way for some complex time-variant systems to run their real-time simulation on a PC cluster.     

Optimised radiative cooling of infrared space telescopes and applications to possible missions

General principles are outlined for the design of space infrared telescopes intended to cool by radiation to the lowest temperatures attainable without the use of on-board cryogens, and assuming on-orbit cooling after a warm launch. Maximum protection from solar and earth heating, maximum radiating area and efficiency and minimum absorbing area and absorptivity are the obvious basic criteria. The optimised design is a short, fat telescope surrounded by a series of radiation shields, each cooled by its own radiator. Maximising the longitudinal conductivity of the radiation shields and of the telescope tube itself is important both to the on-orbit cooling time and the final achieveable temperature. Realistic designs take between 80 and 200 days to cool to within a few degrees of equilibrium temperatures, depending on the materials used. Great advantages accrue from the use of an orbit distant from earth. Both simple models and detailed simulations suggest that temperatures of 30 to 40 K are attainable in high earth orbits. Placing a radiatively cooled telescope in a halo orbit around the Lagrangian point L2 is a particularly attractive option and significantly lower temperatures can be achieved there than in Earth orbit. Optimised radiative cooling is an important element of the small Japanese mission SMIRT. We suggest that a combination of an ESA Medium-sized Mission with a NASA Explorer to send a 2m+ telescope to an L2 halo orbit would provide a cost-effective and powerful long-duration facility for the early 21st century.     

某型直升机半物理仿真系统的设计

飞控计算机是现代直升机控制的不可缺少的设备,研制功能完善的高性能飞控计算机是直升机发展的重要一步。在飞控计算机应用到直升机上之前,需要对其进行较为全面的仿真测试。本文结合飞行控制律的设计,开发了用于对飞控计算机进行全面测试的半物理仿真系统。主要完成了模型的建立和仿真;研制了基于嵌入式操作系统VxWorks及仿真工具软件MATLAB的主仿真系统,并进行了调试。通过对其开环和闭环的调试以及仿真结果的分析表明,该系统对发送的飞机姿态信息能够进行实时显示和处理,满足飞行品质技术指标要求,半物理仿真结果可真实可靠地反映直升机的飞行过程。     

空间站姿态控制系统实时仿真研究

研究了五棱锥构型的单框架控制力矩陀螺群作为执行机构的空间站姿态控制系统的实时仿真问题.根据空间站姿态控制系统的实时分布式仿真要求设计了仿真节点结构,综合了四种网络连接形式构建系统的实时网络环境,说明了仿真系统软、硬件平台的选择,以及系统仿真中的调度设计问题.最后对整个系统进行了分布实时仿真,运行结果说明了这种空间站姿态控制系统方案是可行的.     

飞机平显火控系统仿真的设计与实现

分析了平显火控系统仿真的硬件、软件设计方法,重点讨论了平显火控系统仿真的硬件组成和应用软件设计、平显画面和面板仿真的实现。其特点是开发方便,人机界面良好。     

26 m射电望远镜副面调整机构误差分析

新疆乌鲁木齐南山26 m射电望远镜（NSRT）采用 Stewart 并联机构实现副反射面（简称副面）五自由度运动调整。为确保并联机构的运动精度能满足射电望远镜高精度的指向要求,对影响副面调整机构运动精度的各项误差进行了分析。几何误差模拟结果显示,为使并联机构达到要求的精度,应保证杆长误差小于0.08 mm,铰链误差小于0.04 mm。通过对实测结果与仿真结果分析比较,得出回零误差是造成并联机构误差的主要原因。由于并联机构的回零检测装置主要由增量式编码器与限位开关组成,其中限位开关反馈信号的异常,会引起并联机构的回零误差,分析得到该因素是造成NSRT副面并联机构工作偏差的主要原因,这对并联机构的误差补偿具有指导意义。     

The use of diamond turned & replicated wolter 1 telescopes for high sensitivity X-ray astronomy

Following the success of Einstein, it is clear that telescopes of very large area (10 cm) with angular resolution (20) are needed for deep X-ray surveys and other observations. After a discussion of these objectives, which form the basis of the NASA LAMAR mission, the design & performance of a five mirror telescope is described. The system was studied for possible flight on Spacelab to undertake observations & to act as a prototype module for LAMAR. Both diamond turning & replication methods of mirror production are discussed. The performance of a single Wolter I telescope with diamond turned mirrors will be described.     

单站发射多站接收的空间目标激光测距技术

激光测距作为空间目标测定轨精度最高的技术,对非合作目标的测量精度比微波雷达、光电探测等技术高1～2个数量级,非常有利于非合作目标的精密定位、轨道复核及精确编目,保障在轨空间飞行器的安全。激光在非合作目标表面会发生漫反射,返回光斑弥散、回波微弱,采用大口径望远镜接收系统是必要的。鉴于大口径望远镜研制难度大,提出基于单站发射多站接收的空间目标激光测距新方法,即采用多接收望远镜增加接收面积,实现目标测量能力提升。通过分析单站发射多站接收的激光测距技术特点,基于双望远镜系统开展空间合作目标测量实验,验证了多望远镜接收激光信号的可行性,为该测距技术发展奠定了实验基础。     

基于Monte Carlo的聚焦型X射线脉冲星望远镜多物理场耦合分析方法

聚焦型X射线脉冲星望远镜(XPT)是涉及光学、机械学、热学等多学科的复杂航天载荷,多物理场耦合分析对提高其在轨性能和可靠性至关重要。传统的光机热多场耦合分析(MCA)方法并不能考虑X射线能量及其反射率信息,而且存在学科间数据传递困难的问题。为此,首先基于Monte Carlo和X射线全反射理论提出了一种高效的多物理场耦合分析方法。该方法同时考虑X射线能量和反射率两大特征信息,基于有限元分析(FEA)法建立了XPT热-结构物理场耦合方程和有限元分析模型,针对不同工况进行热分析、结构分析以及热-结构物理场耦合分析。其次,采用Construction Geometry函数分别提取不同工况下光学镜头面形的形变量,并基于多项式函数对变形后的镜头面形进行拟合和误差分析。然后,基于所提方法对变形后的光学系统聚焦性能进行分析与评价,得到镜头形变对XPT光学聚焦性能的影响规律。最后,以多层嵌套的XPT为例,对不同视场角和形变的X射线光学系统聚焦性能进行了仿真分析。结果表明,在全视场时热-结构耦合形变、热形变及结构形变导致XPT聚焦性能分别下降30.01%,14.35%和7.85%,弥散斑均方根依次为2.9143 mm,2.6038 mm,2.5311 mm。通过与试验结果对比分析,验证了所提方法的有效性,可用于XPT的可靠性设计。     

The Rosat mission

The primary scientific objective of the ROSAT mission is to perform the first all sky survey with an imaging X-ray telescope leading to an improvement in sensitivity by several orders of magnitude compared with previous surveys. Consequently a large number of new sources (> 10⁵) will be discovered and located with an accuracy of 1 arcmin. After completion of the survey which will take about half a year the instrument will be used for detailed observations of selected targets.The X-ray telescope consists of a fourfold nested Wolter type I mirror system with 80 cm aperture and 240 cm focal length, and three focal plane detectors. In the baseline version these will be imaging proportional counters (0.1 – 2 keV) providing a field of view of 2⁰ × 2⁰.     

Optical Design for a Cubesat: Unobscured Telescope,Using Freeform Mirrors and a Curved Detector

The possibility of constructing an optical scheme of a telescope for a small satellite based on mirrors with freeform surfaces and a curved photodetector is considered. It is shown that the use of a new element base allows the effective area of the main mirror to be maximized and the field of view up to 9.4 times to be increased in comparison with the classical scheme of the Ritchey–Chretien scheme in ensuring the high image quality.