Design of an assisted natural re-entry scenario for the T4SC project

The increasing concern about space sustainability has led to the establishment of strict regulations regarding satellite end-of-life operations, such as the French Space Operations Act (FSOA). In this context, the French Space Agency (CNES) project Tech for Space Care (T4SC) promotes innovative solutions to ensure regulatory compliance while preserving the technical and economic viability of space missions. Within this framework, the Player One demonstrator is conceived as a minisatellite mission to validate a natural assisted re-entry strategy using deployable membranes to enhance controllability at low altitudes. This approach aims to reduce the reliance on high-thrust deorbit propulsion systems while ensuring compliance with safety requirements and minimizing space debris risks. The purpose of this thesis is to contribute to the system definition and feasibility assessment of the Player One demonstrator atmospheric re-entry. This involves the adaptation and enhancement of CNES-developed simulation tools, including three-degrees-of-freedom and Six-degrees-of-freedom models, to incorporate the new Phase A design provided by the industrial partners. The study focuses on evaluating mission requirements, energy budgets, and controllability during the low-altitude phase of the atmospheric re-entry, while taking into account orbital perturbations, aerodynamic effects, and operational constraints. The methodology relies on sensitivity analyses to identify the critical parameters influencing performance and to guide the definition of robust re-entry strategies. The first part of the thesis presents the satellite system architecture, its mission requirements, and the working environment and simulation tools used to model atmospheric re-entry. Sensitivity analyses are conducted to assess the impact of orbital elements, timing, and membrane deployment on energy consumption and controllability. The second part presents the detailed simulation of the entire re-entry, integrating the updated satellite design and operational parameters. Finally, a controllability analysis of the terminal phase is performed, highlighting the operational limits, performance drivers, and conditions for a safe and compliant atmospheric re-entry. The results provide a comprehensive evaluation of the feasibility of the natural assisted re-entry concept and offer insights applicable to future CNES demonstrators and similar missions.