A Modular CDH to Operate Three-tier Communication System of the Mission Sealion CubeSat

Space missions are becoming increasingly advanced, with requirements that cover a larger number of subsystems than prior missions. These additional requirements create a need for a new approach for the software governing the system’s operation. In this paper, a modular flight software architecture is proposed to support a three-tier communications system being used in the Sealion CubeSat mission, which uses this approach for scientific and communication purposes. The Sealion CubeSat is designed with the objective of studying a new composite deployable payload, and the impedance caused by plasma in the atmosphere. Such a satellite requires a system that is agile to support dynamic payloads which might require precise modifications, and additional unexpected and unimplemented functionality. The design of this architecture shows all modules needed to have an operational system that is non-coupled and abstracted. In this work, all the modules making up the architecture are defined. An explanation of their internal layers and their utilization is provided, plus provisions of the defined interfaces are included. Mission modes that utilize the modules are explained in detail with figures representing visual information. Finally, the paper lists all defined telecommands between a ground station and the current design, which are listed in tables showing their use codes and data requirements.