Archives Ouvertes HAL

Toutes les publications de l'ENAC en direct.
All ENAC publications.

[hal-02298968] Full model-free control architecture for hybrid UAVs

Publications ENAC - Friday, 11 October 2019 - 13:50:36
This paper discusses the development of a control architecture for hybrid Unmanned Aerial Vehicles (UAVs) based on model-free control (MFC) algorithms. Hybrid UAVs combine the beneficial features of fixed-wing UAVs with Vertical Take-Off and Landing (VTOL) capabilities to perform five different flight phases during typical missions, such as vertical takeoff, transitioning flight, forward flight, hovering and vertical landing. Based on model-free control principles, a novel control architecture that handles the hybrid UAV dynamics at any flight phase is presented. This unified controller allows autonomous flights without discontinuities of switching for the entire flight...

[hal-02194727] Les fonctions d'onde externe et interne : une double solution à la Louis de Broglie ?

Publications ENAC - Friday, 11 October 2019 - 03:19:33
Nous proposons une grille de lecture de la mécanique quantique correspondant aux spécifications de la théorie de la double solution de Louis de Broglie. Le principe est de considérer l’évolution d’un système quantique sous la forme de deux fonctions d’onde : une fonction d’onde externe correspondant à l’évolution de son centre de masse et une fonction d’onde interne correspondant à l’évolution de ses variables internes dans le référentiel du centre de masse. La décomposition mathématique exacte n’est possible que dans certains cas car de nombreuses interactions relient ces deux parties. En outre, ces deux fonctions d’onde vont avoir des sens et des interprétations...

[hal-02308208] Design of a high performance MAV for atmospheric research

Publications ENAC - Wednesday, 9 October 2019 - 11:35:13
This article presents the design of a mini UAV dedicated to atmospheric research with tight operational constraints coming from the end-users, which are the meteorologists associated to the project. Several aspects are covered in addition to the conceptual design of the frame itself and its manufacturing process. This includes the innovative launching system based on water rocket, the design of a 5-hole probe for wind and turbulence measurements, the new version of the on-board autopilot and finally the evaluation of a long range communication system. Preliminary results are presented to conclude the paper.

[hal-02301985] Visual Link Routing in Immersive Visualisation

Publications ENAC - Thursday, 3 October 2019 - 03:17:13
In immersive display environments, such as virtual or augmented reality, we can make explicit the connections between data points in visualisations and their context in the world, or in other visualisations. This paper considers the requirements and design space for drawing such links in order to minimise occlusion and clutter. A novel possibility in immersive environments is to optimise the link layout with respect to a particular point of view. In collaborative scenarios there is the need to do this for multiple points of view. We present an algorithm to achieve such link layouts and demonstrate its applicability in a variety of practical use cases.

[hal-02296864] Efficient Rewriting Using Decision Trees

Publications ENAC - Thursday, 26 September 2019 - 03:16:10
Proving programs becomes compulsory as software is increasingly complex. Our work stands in the context of proof interoperability, the global objective is to ease the development of formal proofs. Our work is focused on the development of dedukti, a proof checker implementing the lambdaPi calculus modulo rewriting. This internship is centred on the rewriting engine of the successor of dedukti, namely lambdapi. This memoir starts with a presentation of the theories involved, mainly lambda calculus, rewriting and lambdaPi calculus. The algorithm used in the new rewriting engine is then formalised and a correctness proof is provided. This algorithm is based on the pattern...

[hal-02296003] Creating Accessible Interactive Audio-Tactile Drawings Using Spatial Augmented Reality

Publications ENAC - Wednesday, 25 September 2019 - 13:13:05
Interactive tactile graphics have shown a true potential for people with visual impairments, for instance for acquiring spatial knowledge. Until today, however, they are not well adopted in real-life settings (e.g. special education schools). One obstacle consists in the creation of these media, which requires specific skills, such as the use of vector-graphic software for drawing and inserting interactive zones, which is challenging for stakeholders (social workers, teachers, families of people with visual impairments, etc.). We explored how a Spatial Augmented Reality approach can enhance the creation of interactive tactile graphics by sighted users. We developed the...

[hal-01808649] Piecewise Polynomial Model of the Aerodynamic Coefficients of the Generic Transport Model and its Equations of Motion

Publications ENAC - Wednesday, 25 September 2019 - 03:27:58
The purpose of this document is to illustrate the piecewise polynomial model which has been derived from wind-tunnel measurement data of the Generic Transport Model (GTM) using the pwpfit toolbox. For implementation details and use in MATLAB, please refer to the source code at

[hal-02295361] Co-design of message Structure and Channel Coding Scheme to Reduce the Time to CED and to Improve the Resilience for a Galileo 2nd Generation New Signal

Publications ENAC - Wednesday, 25 September 2019 - 03:19:03
In the recent times, the interest of reducing the time to retrieve the Clock and Ephemerides Data (CED) has provided an open subject of study to design the structure of the message along with the channel coding scheme of the GNSS signals. As a direct consequence, a new methodology to co-design the navigation message and the channel coding scheme structure is proposed in this paper. This new co-design enables both to reduce the time to retrieve the CED and enhanced error correction capabilities under degraded channel conditions. In order to accomplish such as requirements, codes, which provide both maximum distance separable and full diversity properties under the non-...

[hal-02291389] Lower Bound for (Sum) Coloring Problem

Publications ENAC - Friday, 20 September 2019 - 03:18:21
The Minimum Sum Coloring Problem is a variant of the Graph Vertex Coloring Problem, for which each color has a weight. This paper presents a new way to find a lower bound of this problem, based on a relaxation into an integer partition problem with additional constraints. We improve the lower bound for 18 graphs of standard benchmark DIMACS, and prove the optimal value for 4 graphs by reaching their known upper bound.
Back to top