【作者】 张正强；

【导师】 谭跃进；

【作者基本信息】 国防科学技术大学 ， 管理科学与工程， 2006， 博士

【摘要】 由现代智能成像小卫星组成的分布式成像卫星系统是未来对地观测卫星系统发展的主要趋势,分布式成像卫星系统具有智能性和分布性的特点,是一种“敏捷”卫星系统。分布式成像卫星系统的任务规划与控制是在充分考虑分布式成像卫星系统特点的基础上,面向动态观测环境,将多个观测任务没有冲突地分配给分布式成像卫星系统中最合适的卫星执行,并通过自动推理得到各个卫星的具体动作方案,从而自主控制卫星完成各个观测任务。目前,无论是在国内还是国外,对分布式成像卫星系统的任务规划与控制问题的研究都是一个崭新的前沿课题,而且随着现代小卫星系统、分布式卫星系统的快速发展,以及对多星任务规划技术、卫星自主运行技术研究的不断深入,使得本文问题的研究无论是在理论上还是应用上都有非常重要的意义。本文在深入了解分布式成像卫星系统的组成和运行特点的基础上,提出了分布式成像卫星系统的任务规划与控制框架,探索了分布式成像卫星系统的星群任务规划方法、卫星自主控制模型及其求解算法,并最终开发实现了一个原型系统。本文的主要研究内容和创新研究成果如下:首先,在分析成像卫星工作原理及分布式成像卫星系统工作过程的基础上,将整个问题分为两个层次的决策子问题进行求解。根据分布式成像卫星系统的分布性和智能性特点,采用Agent及多Agent系统(Multi-Agent System,简称MAS)的思想研究分布式成像卫星系统,给出了一种高可靠性的分布式成像卫星系统MAS结构及智能成像卫星Agent的分层混合结构模型,并以此为基础,分析了基于MAS的分布式成像卫星系统的任务规划与控制机理与特点,提出了基于MAS的任务规划与控制框架。其次,提出了基于多Agent协商的分布式动态任务规划方法,对传统的合同网协商协议进行改进,提出了基于约束的诚实合同网协议,采用招投标的方式对星群进行任务调度,重点研究了投标活动中任务插入导致的时间窗口约束和电源约束的满足性判断方法,给出了相应的检验算法。根据分布式成像卫星系统的运行特点,提出了基于推进剂消耗和任务均衡指标的各种优化规则,并通过实例研究对各种规则的性能进行了比较,给出了规则使用策略。第三,分析了基于层次任务网络(Hierarchical Task Network,简称HTN)的规划方法对卫星自主控制问题的适用性,给出了相应的求解框架。首先采用规划域定义语言建立了智能成像卫星的规划域模型,然后采用基于HTN的规划方法对卫星自主控制问题进行了求解,开发了两种基于任务网络的导引式状态空间搜索算法。通过实例分析验证了基于HTN的规划方法可以实现对卫星自主控制问题的快速求解。最后,设计实现了一个星座形式的分布式成像卫星系统任务规划与控制原型系统,给出了该系统的一个应用实例,综合验证了本文提出的基于多Agent协商的分布式动态任务规划方法、基于HTN规划的卫星自主控制方法、相应的算法以及原型系统的有效性。更多还原

【Abstract】 Distributed imaging satellite system composed of modern intelligent small imaging satellites is the main earth observing satellite application system in the future. Distributed imaging satellite system is a kind of agile satellite system that is intelligent and distributed. The problem of mission planning and control for the distributed imaging satellite system is defined as: considering the characteristics of the distributed imaging satellite system and the requirement of dynamic observing environment sufficiently, assign various observing missions to the satellites among distributed imaging satellite system optimally. Then generate the detail action plan of every satellite through automatically reasoning, so as to control the satellite autonomously to complete the observing missions. The mission planning and control problem for distributed imaging satellite system is still a brand new problem for researchers either inside or outside the country at present. As the development of modern small satellite and distributed satellite system rapidly, and the research of mission planning technology for multi-satellites and autonomous satellite technology growing on, the investigation on such problems is of great significance both from the theory or application viewpoints. Based on the understanding of components and operation of distributed imaging satellite system, this thesis provides a framework for mission planning and control of distributed imaging satellite system, investigates mission planning technology for satellite cluster, autonomous control model and algorithm for satellite. At last, a prototype of mission planning and control system for distributed satellite system is developed. The main contents and fruits of this paper are outlined as follows:Firstly, this thesis divides the whole problem into two sub decision problems based on analyzing the imaging principle of satellite and the operating process of satellite system. The method based on agent and multi-agent system (MAS) is used to research distributed imaging satellite system according to the distributed and intelligent attributes of distributed imaging satellite system, so as to a kind of MAS structure with high reliability for distributed imaging satellite system and a hierarchical mixed agent structure for single satellite are designed separately. Based on these structures, this thesis analyzes the mechanism of mission planning and control based on MAS, and proposes the mission planning and control framework based on MAS for distributed imaging satellite system.Secondly, this thesis proposes a distributed dynamic mission planning approach based on multi-agent negotiation. This approach improves on the traditional contract-net protocol and a constraints-based honest contract-net protocol is designed eventually, which schedules the observing missions of satellite cluster by means of bidding. The means of feasibility test for mission insertion is presented and the algorithms for verifying the satisfiability of corresponding time window constraint and power constraint are given in detail. According to the operation character of distributed satellite system, the rules of optimizing the fuel consumption and the index of mission trade-off are proposed. This thesis also compares the performance of these rules, and suggests the strategy of utilizing rules.Thirdly, this thesis analyzes the applicability of HTN-based planning approach for autonomous control problem of satellite. The domain model of intelligent satellite is constructed using planning domain definition language, and then the autonomous control problem of satellite is solved by the HTN-based planning approach. This thesis provides two guided state space search algorithms based on task network. At last, an example is given to demonstrate that the HTN-based planning approach can solve the autonomous control problem of satellite effectively.Lastly, this thesis devises and realizes the prototype of mission planning and control system for constellation. In addition, this thesis gives an example and solves it by the prototype system. The results verify the validity of the proposed distributed dynamic mission planning approach for distributed imaging satellite system, HTN-based autonomous control approach for single satellite, corresponding algorithms, and prototype system.更多还原