Software Evolution from TET-1 to Eu:CROPIS

Abstract

The base of the Eu:CROPIS (Euglena Combined Regenerative Organic food Production In Space) Attitude and Orbit Control System (AOCS) is the three layer AOCS software architecture of the TET-1 satellite (Technology demonstrator). Because of different AOCS requirements between TET-1 and Eu:CROPIS, a software reuse is only possible for software components in the interface layer. In the other two architecture layers, the software components have to be replaced by new implementations to fulfil the changed requirements of the Eu:CROPIS mission. In contrast to the former software evolution from BIRD (Bispectral Infra-Red Detection) to the TET-1 AOCS, the software evolution is forced in Eu:CROPIS by the reuse of software design principals applied in TET-1. Without software reuse we are able to change the underlying scheduling mechanisms from a fixed time approach to a more reactive software system presented in this paper.