9H30. Accueil café.
10H00.
Quelques mots pour présenter la démarche dans laquelle s'inscrit cette journée
du point de vue de la DGA
Oratrice : Eva Crück. DGA (Direction Générale de l'Armement).
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10H15. Utilisation des techniques ensemblistes
pour la localisation radio hybride en indoor. Slides.
Orateur : Bernard Uguen (IETR).
Abstract. Si les techniques de localisation en extérieur sont désormais très fiables et permettent d'atteindre de grandes précisions de positionnement, aucun système ne permet encore d'égaler de telles performances en indoor. Ainsi, tout l'enjeu de la recherche dans la localisation indoor est en réalité d'obtenir des précisions équivalentes à celle que l'on peut obtenir en extérieur à l'aide d'un GPS. A défaut de pouvoir s'appuyer sur un système dédié ou qu'il n'en émerge un, les recherches actuelles tendent compenser ce manque par l'utilisation mutualisée des architectures existantes. L'utilisation de cette hétérogénéité est d'autant plus pertinente du fait de la multiplication des techniques de connexion radio disponible sur les terminaux mobiles (3G, LTE-A, Wifi, Bluetooth,UWB IEEE 802.15.4a...). Toutefois, au delà des informations radio, il existe d'autres informations directement disponibles pouvant aider à la localisation mais souvent peu exploitées en pratiques. Ces informations peuvent liées à la connaissance à priori de l'environnement physique (plan de bâtiment), à la capacité d'un terminal à connaître son orientation (accéléromètres, gyroscopes), .... Malgré la diversité et la richesse de ces informations, il n'existe pas encore de solution simple et directe pour toutes les utiliser dans le problème du positionnement.Parallèlement, les méthodes de localisation ensemblistes permettent de transformer naturellement n'importe quel type d'information (radio, physique,...) en une contrainte limitant une zone de l'espace. Une telle description apporte alors un cadre naturel à la fusion de contraintes hétérogènes, et permet in fine d'améliorer la précision du positionnement. Ainsi, dans le cadre du projet européen WHERE 2, nos recherches sont principalement axées sur les solutions permettant d'intégrer les méthodes ensemblistes dans un contexte radio mobile, et sur le développent d'outils de simulation indoor permettant de valider l'intérêt de ces méthodes par rapport à des approches plus classiques, notamment dans des scénarios coopératifs.
10h30. Reliable control using interval analysis. Application to sailboat
robotics. Slides. Paper.
Speaker. Luc Jaulin
(ENSTA-Bretagne, LabSticc).
Abstract. This talk proposes an interval based
method for the validation of reliable and robust navigation rules for mobile
robots. The main idea is to show that for all feasible perturbations, (i) there
exists a safe subset A of the state space such that the robot cannot escape as
soon as it enters in it and (ii) if the robot is outside A, it cannot stay
outside A forever. The methodology will be illustrated on the line following problem of a sailboat
robot. A validation on actual experiment made on January 2012 is presented. In
this experiment the sailboat robot, named Vaimos,
has gone autonomously from
11h00. Set membership methods applied to underwater robotics. Slides.
Speaker. Fabrice Le Bars and Jan Sliwka (ENSTA-Bretagne, LabSticc).
Abstract. In this talk we will present the recent
developments in set membership methods for the localization and SLAM of
underwater robots. We will present the theory used to solve such problems in a
more general context which is the CSP (Constraint Satisfaction Problem). As
such we will introduce following new set entities: set polynomials (polynomials
with set coefficients), interval accumulators and tubes (interval of
functions), used to represent the solutions. Set polynomials and accumulators
are used to solve problems when there is inconsistent information (the case of
outliers in the sensor measurements). An application to robust localization of
our school's underwater robots ('Sauci'sse' AUV and
'Sterne' Glider) will be presented. The tubes are used to solve a
SLAM problem found during mine detection experiments performed by AUVs 'Redermor'
and 'Daurade' of the DGA. GESMI, a mine localization software will be
presented.
11h50 Guaranteed robust distributed estimation in a network of sensors. Slides.
Paper.
Speaker. Michel Kieffer (joint Work with Jean-Benoist
Léger).
Abstract. This talk presents a guaranteed robust
bounded-error distributed estimation algorithm. It may be employed to perform
parameter estimation from data collected in a network of wireless sensors. The
algorithm is robust to an arbitrary number of outliers. Using interval analysis, one is able, provided that the
network is connected, to evaluate at
each sensor, an outer approximation of the set of all parameter values which are consistent with a
given number of measurements, and with
noise bounds. An application to a robust distributed source localization
problem is considered.
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12h40. Déjeuner buffet (offert par la DGA)
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13h40. On the use of GPS and 3D Road Surface Maps for the Navigation of Road
Vehicles in Urban Environments. Slides.
Speaker. Phillippe
Bonnifait, Heudiasyc,
Abstract. Positioning is of prime
importance in mobile robotics and more specifically for intelligent vehicle
applications. When position information is used in a safety-critical context,
like autonomous vehicle navigation, an integrity method is needed to check that
the positioning error stays within the limits specified for the mission. In
aeronautical navigation, protection levels are defined as bounds on the
position error associated to a given integrity risk. This work aims to compute
a confidence domain in which the user in guaranteed to be located with a given
integrity risk. The possible presence of outliers is handled by the use of
robust set-membership methods.
Sensor measurements and model parameters are prone to errors, which are
often modeled by their probability distribution. In the set-membership working
frame, errors can be represented by intervals, thus making the assumption of
bounded errors. When guaranteed error bounds are unknown or too pessimistic,
error bounds associated with a risk can be used. The risk taken on measurements
is then propagated to the computed confidence domain.
Global navigation satellite systems enable high precision absolute
positioning in open sky environments, but measurements suffer from multipath
and non-line-of-sight propagation in urban areas. Robustness to outliers is
thus needed. To counter the lack of visible satellites in urban canyons,
position is constrained by a 3D map of the drivable space and by using the
proprioceptive sensors embedded in recent vehicles.
This talk presents three positioning methods based on a robust set
inversion via interval analysis with GPS pseudorange measurements:
- Snapshot computation of a position confidence domain, with GPS
measurements and altitude constraint from a digital elevation model.
- Use of a precise 3D model of the drivable space as a positioning
constraint, and observation of the GPS receiver's clock drift.
- Robust pose estimation from a sliding horizon of positions and
proprioceptive measurements, constrained by a 3D map.
These positioning methods have been implemented in real-time and tested with real data in difficult environments for satellite positioning.
14h30. Fault tolerant control based on
set-theoretic methods. Application for multi-sensor systems. Slides.
Speaker. Sorin Olaru (Supélec).
Abstract. The talk will be dedicated to the analysis and design of fault tolerant control (FTC) schemes through the use of set-theoretic methods. In the framework of multisensor schemes, the faults appearance and the modalities to accurately detect them are investigated as well as the design of control laws which assure the closed-loop stability. By using invariant/contractive sets to describe earance and the modalities to accurately detect them are investigated as well as the design of control laws which assure the closed-loop stability. By using invariant/contractive sets to describe