A Model-Based Framework for Early-Stage Analysis of Spacecraft

Model-Based Systems Engineering (MBSE) represents a move away from the traditional, document-centric approach to systems engineering. MBSE has the potential to promote consistency, communication, clarity, and maintainability within systems engineering projects. MBSE also has the potential to address one of the well-known issues of the systems engineering ‘Vee’ model – the late discovery of errors. Airbus Space were interested in the application of MBSE to spacecraft, and a literature review elicited the following research aim: ‘To create an MBSE framework, to be deployed during Phase B of the system life cycle, that is able to capture and communicate spacecraft mission design information; is able to perform dynamic simulation of spacecraft behaviour; and is reusable and applicable to different spacecraft missions’. Research presented in this thesis describes the ‘Spacecraft Early Analysis Model’ (SEAM) as one possible solution. The design science research methodology has been adopted to support the development, demonstration, and evaluation of the SEAM. The SysML-based SEAM spans multiple tools (Cameo Systems Modeler, Microsoft Excel, MATLAB, STK) and provides clear definitions of the mission, system, and concept of operations during Phase B. Through an innovative model structure that incorporates a novel representation of functions and modes, the SEAM is executable. This enables the simulation of the system behaviour in response to ‘Flight Operations Procedures’. The SEAM has been demonstrated via its application to three case studies. Case Study 1 involves a dynamic mass memory analysis of Biomass; a low-Earth orbit, Earth-observation mission. Case Study 2 investigates a critical deployment sequence onboard Biomass. Case Study 3 models the ‘Egress from lander’ sequence of ExoMars, a Mars rover mission. The results of these case studies have been verified and sensitivity analyses have been performed. Qualitative feedback from Airbus Space engineers provides evidenc