A Robust Fault Protection Strategy for a COTS-Based Spacecraft

This paper presents a robust fault protection strategy for a low-cost single-string spacecraft that makes extensive use of COTS components. These components include commercial processors and microcontrollers that would traditionally be considered inappropriate for use in space. By crafting an avionics architecture that employs multiple distributed processors, and coupling this with an appropriate fault protection strategy, even a single-string COTS-based spacecraft can be made reasonably robust. The fault protection strategy is designed to trap faults at the highest possible level while preserving the maximum amount of spacecraft functionality, and can autonomously isolate and correct minor faults without ground intervention. For more serious faults, the vehicle is always placed in a safe configuration until the ground can diagnose the anomaly and recover the spacecraft. This paper will show how a multi-tiered fault protection strategy can be used to mitigate the risk of flying COTS components that were never intended for use in the space environment.