When working with space systems the keyword is resources. For a satellite in orbit all resources are scarce and the most critical resource of all is power. It is therefore crucial to have detailed knowledge on how much power is available for an energy harvesting satellite in orbit at every time—especially when in eclipse, where it draws its power from onboard batteries. The challenge is to maximise operational performance of a satellite, while providing hard guarantees that critically low battery levels are avoided, taking into account these power restrictions. Classic approaches to workload scheduling and analysis are not suitable, because of heterogeneity, interdependencies and system dynamics involved. This paper addresses this problem by a two-step procedure to perform task scheduling for low-earth-orbit satellites exploiting formal methods. It combines time-bounded cost-optimal reachability analyses of priced timed automata networks with a realistic kinetic battery model capable of capturing capacity limits as well as stochastic fluctuations. We also discuss how the time-bounded analysis can be embedded into a workflow that exploits in-orbit current and voltage measurements so as to perpetuate the task scheduling. The core procedure has been exercised in-orbit for the automatic and resource-optimal day-ahead scheduling of G om X–3, a power-hungry 3-unit nanosatellite. We explain how this approach has overcome existing problems, has led to improved designs, and has provided new insights.

中文翻译：

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低轨道电池感知调度：GomX-3 案例

使用空间系统时，关键字是资源。对于在轨卫星而言，所有资源都是稀缺的，而最关键的资源是电力。因此，详细了解轨道上的能量收集卫星每次可以使用多少电量是至关重要的——尤其是在日食期间，它从机载电池中获取电力。挑战在于最大限度地提高卫星的运行性能，同时提供避免电池电量严重不足的硬性保证，同时考虑到这些功率限制。由于涉及异构性、相互依赖性和系统动态，传统的工作负载调度和分析方法并不适用。本文通过两步程序解决了这个问题，利用正式方法对低地球轨道卫星执行任务调度。它将定价定时自动机网络的时间限制成本最优可达性分析与能够捕获容量限制和随机波动的现实动力电池模型相结合。我们还讨论了如何将时限分析嵌入到利用在轨电流和电压测量的工作流程中，从而使任务调度永久化。核心程序已在轨执行 G 的自动和资源优化日前调度 我们还讨论了如何将时限分析嵌入到利用在轨电流和电压测量的工作流程中，从而使任务调度永久化。核心程序已在轨执行 G 的自动和资源优化日前调度 我们还讨论了如何将时限分析嵌入到利用在轨电流和电压测量的工作流程中，从而使任务调度永久化。核心程序已在轨执行 G 的自动和资源优化日前调度唵X-3，一颗耗电的 3 单元纳米卫星。我们解释了这种方法如何克服现有问题、改进设计并提供新见解。