Reusable, modular, and scalable flight software

Embedded flight software (FSW) is often one of the larger costs of creating a spacecraft and while hardware must be procured for each vehicle that is developed, in theory, FSW can be reused. Reusing FSW not only reduces the development costs of multiple similar vehicles but can also help to reduce the integration time when individual FSW applications do not require unit level testing. If several FSW applications are reused, it is also possible that the software integration and incremental testing associated with that integration can be reduced. Additionally, if FSW applications are available “off-the-shelf” they can be selected in such a way that both fractionated and scalable vehicles can be built-up from existing FSW modules. Thus, it appears that an overarching goal of this and coming generations of FSW development should focus on software reuse, application modularity, and functional scalability. This paper will address these three critical issues and discuss how we can achieve these goals in the near term. An example using an attitude determination and control subsystem (ADCS) FSW implementation, which is one of the most challenging, will also be examined in light of these goals.