Distributed computing on emerald: a modular approach for robust distributed space systems

摘要

A modular, distributed bus architecture potentially offers significant advantages throughout a satellite's lifecycle. Specifically this architecture enables... During Ground Integration: - incremental integration of subsystems even if crucial parts, such as the CPU, are delayed. -Using the internet for "virtual integration" between remote locations. On-orbit: - sharing resources with-in a satellite - no cost redundancy, including directly commanding subsystems through the communication subsystem, should the CPU fail. And when extended to a multi-satellite mission: -Multiple satellites to be inter-connected as a single "virtual bus." -Autonomous reallocation and sharing of resources across satellites, including adapting to subsystem failures. -Autonomous experiment coordination. This paper explores the benefits and challenges of single and multi-satellite distributed architectures and the unique strategies they enable. The data architecture for the two satellite Emerald mission is used as an example. Emerald uses an I2C serial bus to connect PICmicro based "smart" subsystems.