Fault Tolerant and Flexible CubeSat Software Architecture

The CubeSat pico-satellite is gaining popularity in both the educational and aerospace industries. Due to a lack of experience and constrained hardware capabilities, most of the university missions have been educational in nature. Cal Poly’s project, PolySat, has gained significant experience from the launch of five CubeSats and has designed an entirely new hardware platform based on the knowledge gained from these missions. This hardware is a significant upgrade from what the previous missions used and has greatly increased the capabilities of the software, including supporting the use of the open source operating system Linux. Leveraging the previous PolySat experience, a new design approach has been followed for the development of a fault tolerant and flexible software architecture. As a result, a set of processes and custom libraries that run within Linux have been designed and implemented. Furthermore, an emphasis has been placed on fault tolerance with two features: a software watchdog and digital command signing capability. Lastly, a survey of related CubeSat projects and software fault tolerance papers has been conducted to determine that this new system is sufficient to meet the desired goals. To my parents, Sue and George Manyak, who’ve never discouraged me from trying anything and made this college experience possible.