Software Development Framework for Small Satellite On-board Computers

Abstract

As the missions and functions of satellites differ, on-board computers used in small satellites are frequently developed individually at the relevant organizations. Although the satellite missions may differ, their complicated software may consist of common functional elements when the software structure is segregated into its functional elements, such as the equipment interfaces, ground communications, and attitude estimation. By recursively using a common software platform for many different satellites, we can expect an improvement in reliability through the mutual utilization of the platform and an increase in productivity from its inter-utilization. Therefore, we have developed a software development framework for the on-board computers used in small satellites. We created this software development framework through the following procedure. First, the basic composition of the on-board software was modularized for each function. The modularized components were then converted into class structures by extracting the similarity of each module. Using class structures, the software can be developed with a reduced amount of coding, and new software modules can be generated easily by simply modifying the code. In addition, the proposed software development framework was created for portability, allowing it to operate on many on-board computers. In this paper, the basic concept of the software development framework and its application to small satellites are described.