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Les pilotes et les contrôleurs pourraient-ils apprendre à faire suffisamment confiance à leurs partenaires ? Une première réponse expérimentale
No full textInternational audienceTo find out whether it is possible to train pilots and controllers to adequately trust their partners, and thus modify their behavior and increase their performance, this study experimentally tested whether individuals’ disposition to trust is influenced by their social learning. Objective measurements related to the task to perform, collected over two successive phases, were used for two different groups of aviation staff. The results highlight a link between swift trust, supervision strategies, and time management and point to the social nature of the disposition to trust. This opens the way to a new experimental approach to the study of behaviors induced by interpersonal trust and to new pedagogical levers for optimizing the activity of ephemeral teams through training.Afin de déterminer s'il est possible de former les pilotes et les contrôleurs à faire confiance à leurs partenaires et d'augmenter ainsi leurs performances, cette étude teste expérimentalement si la disposition à faire confiance des individus est influencée par leur apprentissage social. La littérature rapporte que la disposition à faire confiance a un impact sur le comportement des individus, en particulier lorsqu'il leur est impossible de développer la confiance au fil du temps par le biais d'interactions. Si la disposition à la confiance est de nature sociale, alors il est possible de l'influencer par la formation et d'obtenir ainsi des comportements de confiance mieux adaptés aux activités aéronautiques. Cette étude teste donc, à l'aide de mesures objectives recueillies au cours de deux phases successives, si dans un contexte où deux groupes d'opérateurs différents mais comparables ont une tâche à réaliser, une même induction de confiance rapide modifie de manière observable leur comportement de supervision et de gestion du temps en fonction de leur groupe social. L'ensemble des résultats met en évidence un lien entre la confiance rapide, les stratégies de supervision et la gestion du temps, et souligne le caractère social de la disposition à la confiance. Ils ouvrent la voie à une nouvelle approche expérimentale de l'étude des comportements induits par la confiance interpersonnelle, et à de nouveaux leviers pédagogiques pour optimiser l'activité des équipes éphémères par la formation
Impact de la couche limite sur l'estimation des modes en conduit en présence d'écoulement
No full textAéroacoustique guidée : modélisation, mesure et traitements acoustiquesInternational audienc
Trajectory optimization for fully actuated hexacopters: Enhancing maneuverability and applications
No full textInternational audienceSeveral factors need to be taken into account when generating a feasible optimized trajectory. The optimization process heavily relies on the dynamic model of the system. Currently, there are various drone designs available, categorized based on their actuation status. In this study, we apply a trajectory optimization technique to a fully actuated hexacopter (FA-Hex), which is a new application to the best of our knowledge. This type of vehicle has been successfully integrated into several practical applications. Unlike the under-actuated hexacopter (UA-Hex), the FA-Hex can perform maneuvers with minimal banking angles, significantly enhancing the drone's maneuverability. Our research focuses specifically on trajectory optimization for the FA-Hex and demonstrates the adaptability of our method to different scenarios. We discuss two specific applications: a drone filming without a gimbal joint and a drone with a cable-suspended pendulum. We compare the simulation results with the UA-Hex model to highlight the differences in maneuverability between the two systems. The trajectory optimization is performed offline using CasADi in the MATLAB framework
An inter-comparison exercise between spectrometers and handheld sensors to assess biochemical traits of orchard tree leaves
No full textInternational audienc
Time evolution of Kirkendall porosity in single-phase Ni-based diffusion couples
No full textInternational audienceThe development of the Kirkendall porosity was studied in fcc Ni–30Cr/Ni–10Si diffusion couples at 1176 °C using X-ray tomography, optical and scanning electron microscopy, and multicomponent diffusion simulation. Diffusion experiments were interrupted multiple times to monitor the porosity ex situ by tomography. This allowed tracking the position and size of thousands of pores over tens of hours. Pores detected by tomography were also observed by microscopy to determine the surrounding grain structure. The porosity depth profiles (number density, equivalent diameter, area/volume fraction) derived from 2D cross-sectional observations and 3D tomography were compared and the benefits of both methods discussed. Alloys of different grain sizes were used as starting materials to study the influence of the grain boundary density on the spatial pore distribution. Local analysis showed that pore nucleation was not significantly accelerated on grain boundaries compared to the grain interior, but that pore growth was faster along grain boundaries. The time-resolved pore distribution data indicated that the porosity evolved through both pore movement and growth-shrinkage. These mechanisms were discussed in view of the simulated vacancy flux profile
Deterministic and Probabilistic Decision Models for GSaaS-based Satellite Communication Resource Management
No full textPaper submitted to International Workshop on Planning & Scheduling for Space (IWPSS 2025)International audienceOur research addresses the complex task of scheduling data downloads from satellite constellations to a network of ground stations, considering the diminishing value of data over time and the need for complete datasets. The paper presents two novel models for communication slot allocation: a deterministic model that provides a robust framework for resource management, and a probabilistic model that accounts for the inherent uncertainties in satellite communication scheduling. Through these comprehensive models, we aim to optimize communication schedules for numerous satellite constellations, taking into account diverse access conditions and operational constraints of various ground station networks. Our findings contribute significantly to the field, offering a pathway to enhanced resource management and data exchange efficiency in the evolving landscape of EO satellite communications
An Optimal Quantization-based Unscented Kalman Filter on SE(2): Application to Trajectory Tracking
No full textInternational audienceThis paper introduces an Unscented Kalman Filter (UKF) on the Special Euclidean group SE(2) based on optimal quantization, integrating it within the Invariant Linear Quadratic Gaussian (ILQG) regulator to solve trajectory tracking featuring high-angle variations. Traditional trajectory tracking methods like the Linear Quadratic Gaussian (LQG) regulator often face limitations due to linearization, especially under highly nonlinear model, high-angle maneuvers and/or stochastic uncertainties. The proposed approach overcomes these limitations by employing a sigma-point filter, the Unscented Kalman Filter on Lie groups (UKF-LG) enhanced with optimal quantization. This method improves the accuracy of the covariance computation during the filter's prediction step, enabling better estimation performances to provide robust trajectory tracking in scenarios with significant angular deviations. Simulations demonstrate the effectiveness of the proposed Optimal Quantization-based Left-UKF-LG (OQ-Left-UKF-LG) over the IEKF and standard UKF-LG in complex tracking scenarios. The approach offers promising potential for applications requiring precise tracking in dynamic environments, such as autonomous mobile robots or Unmanned Aerial Vehicles (UAVs)
