Development of a Hardware and Software Redundant Cube Satellite Flight Computer

Abstract

Flight computers (FCs) for cube satellites, or cubeSats, have been unreliable in the harsh environment of space. Radiation single event effects (SEE) and total ionization dose (TID) cause significant failure in spacecraft. Radiation hardened parts can reduce the probability of failure but are two orders of magnitude more costly than commercial parts, placing them beyond the budget of most cubeSat missions. A commonly used alternate method is to use commercial parts and redundancy. Past work in this area offers robustness but is still vulnerable to system-wide failure. The proposed system, the Quatara flight computer system, improves upon past work using three redundant strings of processing elements with majority voting to operate and control a satellite. Although the system requires FC software, the focus of this work is the hardware architecture and FPGA algorithms. The Quatara flight computer system is a recoverable, redundant, single fault-tolerant system with increased robustness for cubeSats to serve low-cost, big data missions for NASA, Department of Defense (DoD), industry, and universities. It contains no proprietary components or software, making alterability and updateability relatively simple.