In-flight alignment of the optical-electronic system of a spacecraft

The problem of refining the parameters of the mutual attitude of the onboard camera and the star tracker installed on a spacecraft is considered. A distinctive feature of the problem statement and solution is that the refinement is based on observations of landmarks that are not geodetically referenced.     

数据驱动的飞行器智能故障诊断系统研究

飞行器装备及试验技术的快速发展带来试验数据的指数级增长,传统的试验数据管理与分析手段已经无法满足装备研制与优化设计的需求;提出一种数据驱动的飞行器智能故障诊断技术,通过将人工智能技术与故障诊断技术相融合,能够从飞行器历史测控试验数据库中,自动获取参数的阀值、数据链特征与关联关系,形成准确的飞行器参数知识模型库;通过构建数据驱动的飞行器智能故障诊断系统,将知识模型库中的知识与实时试验数据进行比对分析,实现实时数据的自动化、智能化判读,进而发现航天飞行器可能存在的潜在故障,提前预测,将风险降低到最小。     

Autonomous navigation system of near-Earth spacecraft

An autonomous navigation system for near-Earth spacecraft is described; this system allows determination of the satellite orbit and prediction of its motion parameters. Radio navigation measurements of GLONASS and GPS satellite systems are used for this purpose. The autonomous navigation system is designated for operation on near-Earth orbits which do not go beyond the navigation areas of GLONASS and/or GPS and on orbits with large eccentricity whose apocenter is at a distance of 50–70 thousand km from the Earth’s surface. The developed methods and algorithms for orbit determination are based on the application of laws of motion dynamics of a spacecraft directly at processing primary phase measurements of the carrier frequency and code pseudo-range using an extended measurement base. Algorithms for determination of motion parameters of the spacecraft and results of simulation and operation of a model system are presented. The possibility of creation of an onboard autonomous navigation system with precision and reliability higher than those of the ground measuring complex is demonstrated.     

Realization of multi-agent planning system for autonomous spacecraft

To achieve fully autonomy of deep space spacecraft, onboard planning is a crucial technology. Though, lots of successful applications about it in spacecraft operations have recently been used in real or experimental flight, the inherent distribution and concurrency of the spacecraft subsystem was not taken into consideration. To improve the efficiency of planning system, a multi-agent planning system (MAPS) of autonomous spacecraft is proposed in this paper. MAPS subdivides the search space into some small ones and every PA manages and operates in its own space. With the help of planning manager agent (PMA), all of the planning agents communicate and cooperate with each other to produce partial plan which satisfied all the constraints of the system. To be capable of describing simultaneous activity, continue time, resource and temporal constraints in MAPS, a new planning formal model is given firstly. As the application of this architecture, an MAPS prototype system for deep spacecraft, which is realized with Java language, is designed.     

A condition-based maintenance policy for a production system under excessive environmental degradation

In this paper a condition-based maintenance model is proposed for a single-unit system of production of goods and services. The system is subject to random deterioration which impacts not only the product quality but also the environment. We assume that the environment degrades whenever a specific level of system deterioration is reached. The proposed maintenance model aims to assess the degradation in such a way to reduce the deterioration of the environment. To control this deterioration, inspections are performed and after which the system is preventively replaced or left as it is. Preventive replacement occurs whenever the level of the system degradation reaches a specific level threshold. The objective is to determine optimal inspection dates which minimize the average total cost per unit of time in the infinite horizon. Cost function is composed of inspection and maintenance costs in addition to a penalty cost due to environmental deterioration. The maintenance optimization model is formally derived. On the basis of Nelder–Mead method, inspection dates as optimal solutions are computed. A numerical example is provided to illustrate the proposed maintenance model.     

卫星的智能规划与调度

以对地观测卫星为例，分析卫星的结构功能和飞行任务的特点，并在此基础上建立卫星智能规划与调度系统。规划与调度系统由卫星模型和推理机组成，其中模型描述卫星结构功能和各种约束条件，推理机分析并解决这些约束条件，形成一个没有冲突的飞行计划。规划与调度系统还具有修正计划的能力，能满足任务删除、更改和新任务插入等需求。     

航天器控制系统的自主诊断重构技术

自主诊断重构是确保航天器控制系统安全可靠自主运行的关键技术之一.本文针对航天器资源严重受限的客观情况,改变传统一味追求华丽算法与豪华配置的设计理念,从航天器的自身特性出发,深入挖掘诊断重构问题的本质,提出基于可诊断性与可重构性评价设计的研究思路.文章首先介绍了航天器自主诊断重构技术的发展现状,分析了当前技术的不足之处并探究了其深层原因;然后,提出了通过可诊断性与可重构性评价设计从根本上提高系统自主诊断重构能力的全新思路,梳理了其研究内容与研究概况;最后,对航天器控制系统自主诊断重构技术的发展趋势进行了展望.     

航天器自主高精度时间管理系统设计

为满足航天器长期在轨飞行期间高精度的时间同步需求,提出了一种航天器自主高精度时间管理系统,将北斗导航定位授时设备和频率综合器两种时钟源系统进行融合使用,两种时钟源系统可根据导航定位状态自主切换,在消除了频率源系统误差累积效应问题的同时,解决了导航非定位情况下时间精度急剧下降的问题.通过建立系统的误差模型,以航天器应用设计实例进行计算分析,结果表明:系统时间同步精度优于37.8μs.研究结果可以为后续航天器高精度时间管理系统设计提供参考.     

基于VNX总线的航天飞行器综合控制系统设计

针对小型化航天飞行器对综合控制系统的需求,结合目前国内外先进飞行器综合航电应用的经验,设计了一种以VITA74总线为基本架构的综合控制系统,使其在性能、功耗、体积等方面产生了大幅提升。利用SiP芯片内部的双核SoC芯片来运行主控程序及导航控制算法等功能,通过芯片集成的接口资源和可编程逻辑资源实现丰富的外围接口。给出了综合控制系统的硬件系统设计、软件系统设计及结构设计方案,并详细介绍了各个功能模块的设计思想。通过相应的性能测试试验,表明该系统工作正常,各项性能指标满足任务需求,可用于未来航天飞行器的使用。     

一类航天器控制系统反馈调度方法研究

针对目前航天器控制系统普遍采用静态调度方式,不能够及时调整计算资源分配的问题,提出了一种基于执行时间测量的计算资源反馈调度算法。该方法一方面保证航天器在工作时间段控制精度达到指标要求,另一方面能够动态调整计算资源与控制增益,降低系统功耗。同时在计算机发生故障时保证航天器控制系统稳定运行。最后通过仿真分析验证了方法有效性。     

智能仓库出入库系统优化研究

针对智能仓库出入库系统作业过程中出现的货物拥堵和设备利用率低等问题,对智能仓库出入库作业特点进行了研究,构建了智能仓库的出入库作业周期模型,采用面向对象赋时 Petri 网的方法建立智能仓库出入库系统的 OOTPN（object oriented timed Petri net）模型,并对模型进行了死锁分析,同时也分析了模型有效性和可靠性。运用 Flexsim 仿真软件对建立的 OOTPN 模型进行仿真优化,实验结果表明,出入库工作能力直接影响堆垛机和处理器的利用率,增加出入库工作组可以有效地提高智能仓库的工作效率。     

Rotational motion control of a spacecraft

This note describes a systematic procedure for the control synthesis of a rigid spacecraft using the energy shaping method. The geometric concept of a mechanical system in a coordinate-independent form is used to derive a control algorithm for the Euler-Poincare equations. The main result of this note is a specialization of the method on the unit quaternion group. This note is concluded with the examples of the potential functions and implementation for the three-axis attitude control problem.     

基于双目定位的离合器下料系统设计

机械臂在生产线上抓取组装完成的离合器后,需要准确地将离合器放置在自动导引车(AGV)的下料位置.针对AGV入库时位置不确定,机械臂无法准确实现下料问题,设计了一种基于机器视觉技术的离合器下料定位系统,并针对AGV尺寸较大、单相机定位存在精度差、定位不稳定的重要问题,采用双目定位提高精度和稳定性.实际使用结果表明:基于VisionPro视觉软件设计的AGV特征识别视觉定位系统具有很好的定位结果,定位精度为±0.5 mm,运行时间小于2 s;能够引导机械臂快速、准确地完成离合器下料任务,满足工业实际应用的需求.     

件货物资装卸输转的自动控制系统

件货物资装卸输转的控制系统实现了变幅单元在一定高度范围内自由升降,伸缩单元的水平伸缩与转弯变向,就地控制与集中控制并存,具有货物识别及统计管理功能,保证货物装卸输转的同步流畅,不仅提高装卸效率,而且降低劳动强度和成本,具有多重现实意义。     

载人航天器自动化测试系统设计与应用

针对现有航天器测试不具备流程化、自动化程控的问题,提出了一种载人航天器自动化测试系统。该系统以测试项目模块化思想为依托,提供了测试子项目设计平台,自动生成测试程序、测试细则文档,自动执行测试程序并实现无人值守,在出现异常时根据程序设计自主跳转或等待人工决策,实时记录测试过程信息,测试结束后自动生成测试报表并评估当前测试是否有效通过。对系统方案、接口方式、部署及管理模式进行了分析,通过型号测试进行了试验验证,该系统实现了测试各阶段流程化、自动化程控,提高了测试效率。     

一种可应用于载人航天器的无线话音通信系统

面向未来空间站等大型载人航天器,传统的有线头戴式话音通信系统受电缆长度限制已无法满足航天员的应用需求。为进一步提高航天员在轨工作的方便性,提出了一种可应用于载人航天器的舱内无线话音通信系统,该系统通过设置蓝牙无线话音适配器的方式,在载人航天器现有话音系统的基础上实现了无线功能扩展。相关测试试验表明,该系统可支持多路无线话音通信,话音清晰可懂,且具备实时性高,操作简便等优点,可以满足航天员在轨话音通信使用需求。     

Robust global stabilization of spacecraft rendezvous system via gain scheduling

The problem of robust global stabilization of a spacecraft circular orbit rendezvous system with input saturation and inputadditive uncertainties is studied in this paper. The relative models with saturation nonlinearity are established based on Clohessey-Wiltshire equation. Considering the advantages of the recently developed parametric Lyapunov equation-based low gain feedback design method and an existing high gain scheduling technique, a new robust gain scheduling controller is proposed to solve the robust global stabilization problem. To apply the proposed gain scheduling approaches, only a scalar nonlinear equation is required to be solved. Different from the controller design, simulations have been carried out directly on the nonlinear model of the spacecraft rendezvous operation instead of a linearized one. The effectiveness of the proposed approach is shown.     

An expert system for design of spacecraft attitude control systems

In the aspect of further development of investigations in automatic theorem proving, complicated systems modeling and analysis of their control systems and making such systems more intelligent, we consider problems of elaboration of a hybrid expert system (ES) for design of gyromoment system of attitude control for spacecraft.