REVLANSYS: Mission and GNC Design of Terminal Entry and Landing Missions for Advanced Re-Entry Vehicles

The ESA REVLANSYS study aims to develop key technologies in the field of Mission Engineering and GNC for autonomous re-entry vehicles, and to derive coherent mission, system and GNC requirements for the specific terminal entry and landing phases. As such, REVLANSYS will provide support to European activities towards an autonomous end-to-end mission for a reusable re-entry system, as the SPACE RIDER, with the objective of performing an end-to-end design of the Terminal Area Energy Management (TAEM), Descent, and landing phases. A preliminary design activity was carried out to evaluate different solutions, including winged vehicles landing on a runway and lifting bodies performing a soft landing with a parafoil. A Multidisciplinary-Design Analysis and Optimization process (MDA-MDO) has been implemented as the instrument to evaluate the performance of the different concepts as a function of key design parameters, and produce optimized solutions that have been traded-off to identify the best option for a detailed Mission and GNC design. A Guidance method has been developed to provide trajectory generation capability from TAEM until landing, and a hybrid Navigation system has been tailored. Mission and GNC performance have therefore been assessed in terms of flying qualities, trajectory, Guidance and Navigation, considering a high fidelity simulation environment adapted to the TAEM and landing scenario. This study resulted in the design of a Mission and GNC solution for the terminal entry and landing phases of a return mission, consistent with the overall mission needs. Also, it allowed identifying the capabilities of the detailed design solution, and the possible limitations and improvements that are necessary to achieve a complete and robust mission and GNC design. Thanks to the knowledge gained during the project, DEIMOS Space Romania (DMR) is now capable of offering Mission Engineering and autonomous GNC solutions for future European re-entry missions. This paper presents the activities carried out and the results obtained in the study, focusing on the detailed design phase