航天器热控系统中的热泵-蓄冷组合方案

提出了旨在降低热控系统质量的热泵-蓄冷组合热控方案。通过对负荷进行预测，对热泵蓄冷系统的集成模式，系统的运行策略，以及蓄冷设备的容量等问题进行了分析。结果表明：通过合理优化系统的运行参数，热泵蓄冷组合方案能实现热控系统的轻量化设计要求，在未来航天热管理系统中具有相当的应用潜力。     

交会对接最后逼近阶段CCD相机的测量方法

本文提出交会对接最后逼近阶段，在ＣＣＤ相（及二极管阵列）任意安装条件下，测量追踪飞行器相对于目标飞行器位置和姿态的方位角法和成象法测量方案，及在采用单机和多机时的算法，并进行了分析比较。在采用单机时，精度很高，而采用双机或多机，算法简单，速度快。将两者结合起来，可以较好地解决该阶段的测量问题。     

十字交叉振子类型圆极化天线的研究

通过对Ｈａｌｌｅｎ方程进行矩量法求解，讨论了十字交叉振子类型天线产生圆极化辐射时两对振子长度选择的方法；计算了几种情况下天线的远区辐射场；指出十字交叉振子、伞型振子等这类天线由于具有结构紧凑、工作可靠、易于赋形等特点，可广泛应用在空间飞行器上。     

高能推进剂主要组分对燃烧效率影响研究

利用燃烧残渣中活性铝含量分析、真空爆热特性和发动机试验手段，研究了高能推进剂中主要组分对推进剂燃烧效率的影响。实验结果表明，增塑剂的种类和含量是影响燃烧效率的主要因素，ＡＰ含量及固体组分的粒度级配也有明显的影响。ＢＳＦХ７５发动机试车结果表明，铝粉粒度级配的改变，可以使高能推进剂比冲效率由０．８８提高到０．９２。     

关于双反射面天线的两个优化问题

在航天器上和地面站中,广泛采用着双反射面天线。本文探讨了双面天线的两个优化问题。当主面为现存的抛物面时,使副面优化赋形,从而比之经典双面(抛物面——双曲面)的增益提高(0.48～0.40)~(dB)(对应于D/λ=20～100)。寻求偏置柱形双反射面系统的最佳设计,使其在馈源方向图变化时,口径场分布最接近同相等幅。     

论航天器的综合环境试验

讨论了在航天器研制中综合环境试验的重要性和必要性,简单介绍了航天器研制中的各种综合环境试验,对如何设计和应用综合环境试验提出了一些看法。     

Relative position and attitude estimation of spacecrafts based on dual quaternion for rendezvous and docking

The capacity to acquire the relative position and attitude information between the chaser and the target satellites in real time is one of the necessary prerequisites for the successful implementation of autonomous rendezvous and docking. This paper addresses a vision based relative position and attitude estimation algorithm for the final phase of spacecraft rendezvous and docking. By assuming that the images of feature points on the target satellite lie within the convex regions, the estimation of the relative position and attitude is converted into solving a convex optimization problem in which the dual quaternion method is employed to represent the rotational and translational transformation between the chaser body frame and the target body frame. Due to the point-to-region correspondence instead of the point-to-point correspondence is used, the proposed estimation algorithm shows good performance in robustness which is verified through computer simulations.     

Analysis and implementation of in-plane stationkeeping of continuously perturbed Walker constellations

The stationkeeping of symmetric Walker constellations is analyzed by considering the perturbations arising from a high order and degree Earth gravity field and the solar radiation pressure. These perturbations act differently on each group of spacecraft flying in a given orbital plane, causing a differential drift effect that would disrupt the initial symmetry of the constellation. The analysis is based on the consideration of a fictitious set of rotating reference frames that move with the spacecraft in the mean sense, but drift at a rate equal to the average drift rate experienced by all the vehicles over an extended period. The frames are also allowed to experience the J₂-precession such that each vehicle is allowed to drift in 3D relative to its frame. A two-impulse rendezvous maneuver is then constructed to bring each vehicle to the center of its frame as soon as a given tolerance deadband is about to be violated. This paper illustrates the computations associated with the stationkeeping of a generic Walker constellation by maneuvering each leading spacecraft within an orbit plane and calculating the associated velocity changes required for controlling the in-plane motions in an exacting sense, at least for the first series of maneuvers. The analysis can be easily extended to lower flying constellations, which experience additional perturbations due to drag.     

Development of in-situ Space Debris Detector

Due to high relative velocities, collisions of spacecraft in orbit with Space Debris (SD) or Micrometeoroids (MM) can lead to payload degradation, anomalies as well as failures in spacecraft operation, or even loss of mission. Flux models and impact risk assessment tools, such as MASTER (Meteoroid and Space Debris Terrestrial Environment Reference) or ORDEM (Orbital Debris Engineering Model), and ESABASE2 or BUMPER II are used to analyse mission risk associated with these hazards. Validation of flux models is based on measured data. Currently, as most of the SD and MM objects are too small (millimeter down to micron sized) for ground-based observations (e.g. radar, optical), the only available data for model validation is based upon retrieved hardware investigations e.g. Long Duration Exposure Facility (LDEF), Hubble Space Telescope (HST), European Retrievable Carrier (EURECA). Since existing data sets are insufficient, further in-situ experimental investigation of the SD and MM populations are required. This paper provides an overview and assessment of existing and planned SD and MM impact detectors. The detection area of the described detectors is too small to adequately provide the missing data sets. Therefore an innovative detection concept is proposed that utilises existing spacecraft components for detection purposes. In general, solar panels of a spacecraft provide a large area that can be utilised for in-situ impact detection. By using this method on several spacecraft in different orbits the detection area can be increased significantly and allow the detection of SD and MM objects with diameters as low as 100 μm. The design of the detector is based on damage equations from HST and EURECA solar panels. An extensive investigation of those panels was performed by ESA and is summarized within this paper. Furthermore, an estimate of the expected sensitivity of the patented detector concept as well as examples for its implementation into large and small spacecraft are presented.     

航天器电线电缆寿命预测模型研究

随着航天器复杂大系统的高速发展，以及器上电子产品的广泛应用，使得电线电缆大量应用于复杂系统之间的功率输送和信号控制。在航天器运行过程中，电线电缆由于受到空间布局限制，交叉重叠；同时受振动、温度、空间辐射等外部环境影响，致使电缆老化进而引发其他电气故障。介绍了基于可测特征参数的寿命模型建立方法，得出电缆剩余寿命的预计模型，开展航天器电线电缆老化机制以及寿命预测模型研究，最终实现航天装备电缆寿命预测的能力。