Orbit Determination for Navigation Analysis and Maneuver Planning - The Argonaut Mission

Long-term sustained access to the Moon has become a major global priority in space missions. In recent years, extensive research and discoveries have led space agencies and companies worldwide to conduct multiple feasibility studies aimed at establishing permanent infrastructure and assets both in the cis-lunar environment and on the lunar surface. The European Space Agency (ESA) is advancing its lunar exploration efforts with Argonaut, a European lunar lander integrating with Lunar Link, Gateway, and the Moonlight communication and navigation systems. As a significant component of Europe’s contributions to international lunar initiatives, Argonaut is designed to integrate with future lunar infrastructure and may eventually support NASA’s Artemis program and commercial lunar lander services, contributing to the establishment of a sustainable human presence on the Moon. Thales Alenia Space Italia plays a crucial role in the development of the lander, and this research has been carried out as part of its work on Argonaut. The focus is on developing navigation and orbit determination strategies to enhance trajectory analysis, optimize mission planning, and ensure operational reliability in the lunar environment. The aim of this dissertation is the implementation of an Extended Kalman Filter (EKF)-based navigation framework for satellite orbit determination. The research integrates “real-world” aspects such as measurement errors, atmospheric delays, and stochastic disturbances to enhance the accuracy state estimation A key component of this work is the evaluation of the measured distance between the observer and target (range) and their observed relative velocity (range-rate) using ground station data. Ionospheric and tropospheric corrections are applied to improve the accuracy of the computed pseudorange and Doppler shift. To evaluate the performance of the proposed navigation system, a covariance analysis is conducted, identifying crucial phases where trajectory corrections are necessary to maintain adherence to the nominal path. The analysis supports the implementation of a flight path control strategy, leveraging error propagation models to determine the optimal timing for corrective maneuvers. The implementation of orbit determination algorithms and the evaluation of their performances have been carried out in MATLAB environment, utilizing the SPICE NAIF toolkit for reference frame transformations and state vector computations. Results are assessed against the ESA guidelines for the Argonaut mission, highlighting the robustness of the EKF approach across different levels of measurement noise and visibility conditions. Additionally, analyses were conducted using Systems Tool Kit (STK) to validate some results of this work, further ensuring their robustness and applicability in real-world scenarios. The insights gained from this study contribute to the broader field of autonomous satellite navigation, with applications extending to planetary missions and deep-space exploration.