Unmanned Aerial Vehicles (UAVs) are complex systems whose complexity lies mainly in the plurality of their missions. Among aerospace vehicles with various missions (aircraft, satellite, etc.), UAVs have the advantage of being easily scalable due to their small size. Thus, the missions developed should be relatively easily implementable, raising the need for genericity. For this reason, this paper discusses multiple tools and methods used to model a UAV mission. Starting from a Simulink State flow model, a top-level mission architecture was created, and operational, functional, and logical analyses were conducted using an ARCADIA/Capella based approach.

This paper discusses the feasibility of the on-board robust guidance implementation for an autonomous asteroid rendezvous operation. Due to the complexity of the optimization prob- lem and the presence of the several uncertainties, spacecraft on-board guidance is quite chal- lenging. Furthermore, implementing the algorithm on an actual on-board computer is not a simple task considering the performance and the coding resources. This paper compares the chance-constrained stochastic optimal control algorithm with the model predictive control algorithm and the feedback convex optimization algorithm, and analyzes the guidance per- formance. It is concluded that the chance...

In the past few years, the interest in the development of missions to asteroids of our Solar System has grown at an accelerating rate. For this reason, in this work, different techniques have been explored, supplying the reader with multiple different tools to be used when deal- ing with an asteroid mission planning. The ultimate goal is, thus, to provide a complete view and comparison of some possible dynamics models, trajectory optimization approaches and solution algorithms for a spacecraft asteroid rendezvous. This work departs from the most important trajectory optimization techniques, adapting and optimizing them in order to create new efficient algorithms able to...

Autonomous spacecraft operation during the asteroid rendezvous phase is still a chal- lenging problem due to the complexity of the optimization problem. Since the on-board computer has limited capability, the computational load has to be as cheap as possible. In order to solve the highly constrained optimization problem, the convex optimization is adapted to generate the nominal trajectory for the asteroid rendezvous phase. Since the original problem is not convex, the problem is convexified using lossless convexification and successive convexification. The developed algorithm is applied to the rendezvous approach for asteroid Ryugu, and the optimal trajectory is...

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Drones are increasingly being deployed to assist firefighting crews in their missions, with the technology being chosen based on availability, rather than aligned with their specific needs. This phenomenon is exacerbated in the Global South, where infrastructure is scarce and where specific processes and user needs have to be adequately mapped to successfully introduce new technologies. We conducted semi-structured interviews with firefighting professionals (N=15) from Thailand, covering their prior experience with drones, challenges they encounter in their job, and how they envision this technology could better support them in the future. Our findings describe users’...

Recent works on smart scanning techniques in Raman micro-imaging demonstrate the possibility of highly reducing acquisition time. In particular, Gilet et al. [Optics Express 32, 932 (2024)] proposed a protocol combining compression in both spectral and spatial domains by focusing on essential information. This protocol consists of a two-pass scan in Raman modality at different signal-to-noise ratios (SNR). The first scan of the entire sample area at low SNR, and was identified as the bottleneck of the whole process. We propose revisiting this protocol by replacing this first scan with scanning electron microscopy (SEM), which is a faster imaging modality. We demonstrate...

This paper introduces the architecture of a localization system designed for commercial airliners. The system is designed to maintain guidance during an PBN CAT I approach in a GNSS-challenged environment. It leverages a vision sensor to observe the aircraft’s surroundings. Specifically, this new sensor allows for the detection and tracking of the runway during the final segment of the approach, providing line-of-sight information to the system. The vision sensor is integrated into a multi-sensor system that includes a high-precision navigation-grade Inertial Measurement Unit (IMU) (angular drift of the order of 0.01 degree per hour), a barometric altimeter, and a GNSS...

Cette thèse porte sur l’étude statistique des trajectoires d’aéronefs. Dans un premier temps, nous proposons une revue de la littérature qui permet d’identifier les approches statistiques pertinentes dans l’analyse de données de trajectoires. Le cadre de l’analyse statistique des données fonctionnelles est particulièrement instructif car il met en lumière deux défis majeurs dans le traitement de telles données : la nécessité de reconstruire les trajectoires pour les évaluer à différentes résolutions temporelles, ainsi que l’existence de variations de phase qu’il est important de corriger sur le plan statistique. La reconstruction de données de trajectoires présente des...