Distributed asynchronous planning and task allocation algorithm for autonomous cluster flight of fractionated spacecraft
Distributed asynchronous planning and task allocation algorithm for autonomous cluster flight of fractionated spacecraft
复制标题
DOI：
10.1504/ijspacese.2014.060597
复制
发表时间：
2014-04
期刊：
影响因子：
--
通讯作者：
Jing Chu;Jian Guo;E. Gill
中科院分区：
文献类型：
--
作者：
Jing Chu;Jian Guo;E. Gill
对于分块航天器的自主集群飞行，规划和任务分配是重要的，因为它们在分布式空间系统的顶层（解释来自环境的输入）和底层（本地控制器）之间架起了桥梁。本文提出了一种异步分布式算法，该算法可以同时实现规划和任务分配，而不是逐个执行。首先，将规划和任务分配问题一般化。然后提出了核心算法，该算法由两个部分之间的迭代组成。一是构建要分配的任务列表和每个模块上的任务分配。另一个是通过在相邻模块之间交换本地信息来实现不同模块结构之间的共识过程，其中为异步情况量身定制了冲突消除规则。前者是基于竞价算法，后者是基于共识算法。整个流程在这两个部分之间异步迭代，直到所有模块都同意计划和任务分配。仿真结果表明，该算法不仅适用于分体航天器在标称条件下的运行，而且适用于分体航天器在网络中断或新任务下的运行。
For autonomous cluster flight of fractionated spacecraft, planning and task allocation are important as they bridge the gap between the top-level layer (interpreting inputs from the environment) and the bottom-level layer (local controllers) of the distributed space system. This paper presents an asynchronous distributed algorithm that is able to implement planning and task allocation concurrently, instead of one-by-one. First of all, the planning and task allocation problem is formulated in a generalised way. Then the core algorithm is presented, which consists of iterations between two parts. One is the construction of the list of tasks to be allocated and the assignment on-board each module. The other is the consensus process among different constructions of modules by exchanging local information between neighbours, where deconfliction rules are tailored for asynchronous situations. The former part is based on an auction algorithm, while the latter one takes advantage of a consensus algorithm. The entire process iterates asynchronously between those two parts until the planning and task allocation are agreed by all modules. In this paper simulation results are presented, which demonstrate the performance of the asynchronous algorithm not only when fractionated spacecraft operate under nominal conditions, but also when it experiences network disconnects or new tasks.