Small Sats Lifecycle Management Through MBSE Aided Decision Making Tailored Tool

Traditional System Engineering approaches highlight some bottlenecks whenever dealing with information exchange among stakeholders, typically producing many documents, difficult to trace and to keep harmonized. This is particularly true for space applications, which entail very complex systems conceivement, design, implementation and operation by a number of different players who grow with mission complexity. Model-Based Systems Engineering (MBSE) is intended to facilitate these activities, providing a common source of truth to the system engineering “ecosystem”, improving its efficiency and quality by applying a model that evolves along the entire product lifecycle. The paper proposes a critical analysis of an MBSE approach applied to real small sat mission currently under the European Space Agency (ESA) phase A study, demonstrating its potential and its gaps. All Systems Engineering phases are explored, from the high-level mission objectives definition, through the articulated external and internal functional analysis, down to concept of operations, ending up with the Assembly, Integration and Verification/Test plan definition; every modelling step is harmonized with proper requirements generation and their role in driving the logical and physical trade-off analyzes. The study is conducted according to the ARChitecture Analysis & Design Integrated Approach (ARCADIA) and adopting the Capella tool, being very effective in mastering different engineering levels with coherence and with an iterative information refinement. Despite the clear advantage of having a unique model in which a change is inherently shared with all stakeholders, saving up time in communication, MBSE still lacks intelligent support that could strongly help in addressing the best optimal architecture in line with the system functionalities, speeding up the alternatives selection process. This would be particularly useful during the preliminary design phases, in which the almost infinite design choices are skimmed by the only systems engineers’ knowledge, who may miss some solutions. A newly approach conceived to solve this issue is here presented in the form of a decision-making tool prototype, that correlates a set of functionalities with a set of available technologies, proposing one or more architectures that are coherent with what the engineers expect from the system behaviour; a first grid of requirements is also part of the tool output, in support of the previously described MBSE approach.