Simplifying Avionics Design and Demonstration: A Unified Module Framework for Spacecraft Avionics

Abstract

A successful in-orbit demonstration is the best argument for an innovative spacecraft avionics technology to be widely adopted. Opportunities to demonstrate technologies on larger, classical spacecraft are rare, costly, and usually face long development cycles. Meanwhile, there are plenty of affordable flight opportunities for standardised CubeSat-style nano-spacecraft on almost every rocket launched today. If avionics systems intended for classic spacecraft could be tested and demonstrated in a small spacecraft without much customization, especially in terms of the mechanics and interfaces, the development cycle could be accelerated a lot. This paper presents the work towards addressing this possibility and the resulting Unified Module Framework (UMF) that can be used to provide core avionics modules for a wide range of spacecraft classes and applications. Based on the Advanced Data Handling Architecture (ADHA) initiative by ESA, the feasibility of physically integrating cPCI Serial Space modules, intended for larger spacecraft, into a commercial CubeSat structure is evaluated first. Subsequently, a set of physical constraints are formulated and a design is created that is capable to scale from being used in a standard 3U structure to the integration in a classic box design for larger spacecraft. Secondly, the paper discusses the tailoring of cPCI Serial Space and extensions made, in order to enable building practical systems with UMF. UMF defines some choices for the physical interfaces within the cPCI standard, in order to ensure the electrical and functional compatibility between all modules that use it. Further, cPCI Serial Space does not prescribe a power supply solution for systems using it. UMF addresses this and goes beyond by also including electrical power system components in its architecture. Finally, the paper discusses the practical use of UMF based on an example application, intended to be the first in-orbit demonstration of the proposed UMF framework.