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In most of the missions a mobile robot has to achieve – intervention in hostile environments, preparation of military intervention, mapping, etc – two main tasks have to be completed: navigation and 3D environment perception. Therefore, vision based solutions have been widely used in autonomous robotics because they provide a large amount of information useful for detection, tracking, pattern recognition and scene understanding. Nevertheless, the main limitations of this kind of system are the limited field of view and the loss of the depth perception. A 360-degree field of view offers many advantages for navigation such as easiest motion estimation using specific properties on optical flow (Mouaddib, 2005) and more robust feature extraction and tracking. The interest for omnidirectional vision has therefore been growing up significantly over the past few years and several methods are being explored to obtain a panoramic image: rotating cameras (Benosman & Devars, 1998), muti-camera systems and catadioptric sensors (Baker & Nayar, 1999). Catadioptric sensors, i.e. the combination of a camera and a mirror with revolution shape, are nevertheless the only system that can provide a panoramic image instantaneously without moving parts, and are thus well-adapted for mobile robot applications. The depth perception can be retrieved using a set of images taken from at least two different viewpoints either by moving the camera or by using several cameras at different positions. The use of the camera motion to recover the geometrical structure of the scene and the camera’s positions is known as Structure From Motion (SFM). Excellent results have been obtained during the last years with SFM approaches (Pollefeys et al., 2004; Nister, 2001), but with off-line algorithms that need to process all the images simultaneous. SFM is consequently not well-adapted to the exploration of an unknown environment because the robot needs to build the map and to localize itself in this map during its world exploration. The in-line approach, known as SLAM (Simultaneous Localization and Mapping), is one of the most active research areas in robotics since it can provide a real autonomy to a mobile robot. Some interesting results have been obtained in the last few years but principally to build 2D maps of indoor environments using laser range-finders. A survey of these algorithms can be found in the tutorials of Durrant-Whyte and Bailey (Durrant-Whyte & Bailey, 2006; Bailey & Durrant-Whyte, 2006). 1

A wireless sensor network (WSN) deployment requires the identification of optimal network nodes (sensor and sink) positions in an area of interest, to ensure the best network performances (Senouci et al. in Smart Communications in Network Technologies (SaCoNeT), 2014 International Conference on, IEEE, pp 1---6, 43). The deployment process can be divided in two main parts: (1) WSN model construction, and (2) placement optimization. Few research works were interested by WSN deployment in indoor environment, even though, most of them consider the objectives (coverage, cost, connectivity) individually without considering the sensors and sink in the same time. This paper proposes a multi-objective deployment strategy (MODS), where all important objectives are integrated. The MODS uses the multi-objective evolutionary algorithms to get near optimal solution for WSN deployment problem. An original coding solution, integrating both network cost and nodes positions is proposed. A comparative study between two evolutionary strategies (classical GA, and NSGA-II) was performed to identify the use case of each one. Obtained results showed the interest of the proposed methodology.

International audience; Maintenance of offshore wind turbines is a complex and costly undertaking which acts as a barrier to the development of this source of energy. Factors such as the size of the turbines, the size of the wind farms, their distance from the coast and meteorological conditions make it difficult for the stakeholders to select the optimal maintenance strategy. With the objective of reducing costs and duration of such operations it is important that new maintenance techniques are investigated. In this paper we propose a hybrid model of maintenance that is based on multi-agent systems; this allows for the modelling of systems with dynamic interactions between multiple parts. A multi-criteria decision algorithm has been developed to allow analysis and selection of different maintenance strategies. A cost model that includes maintenance action cost, energy loss and installation of monitoring system cost has been presented. For the purposes of this research we have developed a simulator using NetLogo software and have provided experimental results. The results show that employing the proposed hybrid maintenance strategy could increase wind farm productivity and reduce maintenance cost.

In this paper we propose models for solving both the layout manufacturing problems and the scheduling manufacturing systems. These models are based on Coloured petri Nets. The particularity of our models is the possibility to include complex programmable functions inside the petri nets models. In our case the programming language is SML/NJ. The advantage of programming language is the possibility to use Heuristics or Meta-heuristic optimization methods inside the Coloured Petri Nets (CPN) model without the necessity to relaunch the simulation of the model at each step of optimization. For describing, analysing and simulating our models we will use CPN Tools.

Maintenance is a crucial point to improve productivity in industry whereas systems to be maintained have an increasing complexity. Augmented Reality (AR) can reduce maintenance process time and improve quality by giving virtual information and assistance to the operator during the procedure. In this paper, a workflow is firstly presented allowing a maintenance expert to author augmented reality maintenance procedures without computer skills. Then the AR maintenance application developed is described. Based on it, we present a case study which aims to compare maintenance efficiency with respect to the market available media support used, i.e. paper, video, AR tablet or AR Smart Glasses. A set of experiments involving 24 persons is described and analyzed. The results show that augmented reality maintenance reduce number of errors done by operator than with paper for the same duration of maintenance. A qualitative analysis shows that AR systems are well accepted by the users.

In this paper, a parametric electromagnetic radiated emis- sion model has been explored. Several mathematical improvements with respect to its extraction and computational performance have been deployed. The model, represented with an array of radiating electric dipoles, predicts the electromagnetic emission of components and systems. Core-level changes have been made in order to extract the model parameters: the dipole positions, their orientations and cur- rents, and the efiective relative permittivity from near-fleld measure- ments. Thresholding and windowing techniques are used to detect and optimize dipole positions, directly from the fleld data. A fast and mem- ory e-cient two-level optimization algorithm based on the Levenberg- Marquardt non-linear least squares technique is implemented for para- metric extraction. All the constraints of the previous model have been overcome and the system is validated for mono-substrate and multi- substrate devices from measurements and/or simulations, with promis- ing results. A tremendous improvement in modeling capability and performance has been obtained when compared with that of its erst- while counterpart.

As the first part of a study that aims to propose tools to take into account some electromagnetic compatibility aspects, we have developed a model to predict the electric and magnetic fields emitted by a device. This model is based on a set of equivalent sources (electric and magnetic dipoles) obtained from the cartographies of the tangential components of electric and magnetic near fields. One of its features is to be suitable for a commercial electromagnetic simulation tool based on a finite element method. This paper presents the process of modeling and the measurement and calibration procedure to obtain electromagnetic fields necessary for the model; the validation and the integration of the model into a commercial electromagnetic simulator are then performed on a Wilkinson power divider.

This paper presents a heuristic optimized model for describing the electric- and magnetic-radiated emissions from passive microwave components. The main idea has been derived from a previously built model at the Research Institute for Embedded Electronic Systems, which models only the radiated magnetic field. The modeling procedure is based on the use of elementary dipoles. The model extraction is a two-step technique: extraction of the initial dipole parameters (namely their orientation and currents) and an optimization. The Levenberg-Marquardt algorithm is used in order to optimize the dipole parameters, keeping in mind their physical sense. The tangential components of the measured magnetic field are used to build the model.

This article presents a theoretical characterization of the regular polygonal waveguide (RPW) having n-sides. Based on the symmetrical circular symmetry of the RPW and the circular waveguide (CW), the analogy between the electromagnetic (EM) behaviors of these to waveguide (WG) is established. After a brief recall about the state of the art concerning the WG engineering and its application, we introduce a basic theory of the WG presenting a regular polygonal cross-section with n-sides. By considering, the fundamental mode TE11, we develop the main mathematical formulas summarizing the difierent characteristics (cut-ofi frequency, fc, propagating constant, k11 and S-parameters) appropriated to any RPW in function of its physical parameters (number of sides, n, diameter, D and height, h). In order to verify the validation of the developed analytical expressions, comparisons between the HFSS simulated and theoretical dispersion diagrams of regular pentagonal (n = 5), hexagonal (n = 6), heptagonal (n = 5) metallic (copper) WG with for example, 50mm outer diameter are presented. So, it was demonstrated that very good correlation between the theoretical predictions (fc(n), k11(n)) is found with a relative error less than 1%. As application of the present study in terms of EM wave shielding, simulation of metallic wall with hexagonal aperture is also performed. Finally, discussion about the future work is drawn in conclusion.

Part 1: Knowledge Discovery and Sharing; International audience; The product lifecycle management (PLM) system has a significant role to support the collaboration and manage the partnership between OEM and supplier to enable the success of supplier integration. Today great rates of cooperation as suppliers have been dedicated to SMEs.Since one of the PLM task is to control the collaboration between OEM and suppliers, this paper provide supplier (SMEs) a framework to find their level of relationship with OEM and the steps that they can improve it. To respond to this trend, we defined a methodology based on collaborative matrix maturity levels and four PLM axes of strategic, organization, process and tools levels. Finally according to this matrix, we proposed a structure of a proper questionnaire and example that shows suppliers how to evaluate their positions in terms of collaboration in PLM.

Nowadays, Wireless Sensor Networks (WSN) are a commonly used technology in Smart Buildings applications. Generally, WSN suffer from finite energy resources (limited lifetime), and limited network coverage (due to transmission range). The most consistent works on energy consumption and radio transmission modeling for WSN, are not taking into account realistic constraints. However, radio propagation is affected by a lot of kinds of obstacles (walls, windows, doors...) with different effects on the radio propagations. For this, a proper and more realistic radio propagation model is essential to optimize energy consumption and ensure network reliability (best network coverage). In this paper, we investigate the impact of the radio propagation modeling on the network energy consumption with and without obstacles (walls) consideration. This work leads to evaluate a proper radio behavior model with the objective to use it in an optimization process.

Recently, wireless sensor networks are more and more used in smart building applications, due to their capability to collect data on all phenomena that happens in the building. The most important problem related to this kind of networks, is the limited lifetime of nodes, caused by their finite embedded source of energy (batteries). In order to reduce the impact of this problem, proper node model must be defined. In this work, we propose a behavior modeling of a sensor node. We evaluate the performance of our model and show the impact of the number of nodes and their placement on the maintenance cost of network. Presented results can provide guidelines for real sensor network deployment.

A radiated emission model, scaled, optimized, and compatible to modelling “on-chip” microwave devices is presented in this paper. The model has been inspired from a previously existing model at IRSEEM, which predicts only the radiated magnetic field. The proposed model predicts the radiated electromagnetic (EM) emissions of components of very small form factor. An optimization procedure has been implemented in order to extract the model parameters, taking into account their physical sense. The model is applied to an “on-chip” microstrip patch antenna, designed and simulated in Ansoft HFSS. The antenna is built on a High Resistivity Silicon substrate and resonates at 20 GHz. Promising and encouraging results have been obtained for the modelled radiated EM fields. Our model is proven suitable to apply on System-in-package and System-on-Chip devices integrating wireless system within itself.

This paper presents the HF models of multi-wikdikg traksformer used ik switching power supplies for radar applications. It allows the adaptatiok of voltage levels for keeds akd provides galvakic isolatiok betweek ikput akd output. Two models of the HF traksformer are presekted: a simplified model akd a model takikg ikto accoukt the couplikg of leakage ikductors. The accuracy of each model is established by comparikg the simulatiok results of cokducted electromagketic disturbakces to measure results.

International audience; This paper presents a 3-second 3D reconstruction algorithm able to process a dense geometric approximation of the surrounding environment. Image acquisition is done by a stereoscopic panoramic system with two color catadioptric cameras mounted on a mobile robot. An algorithm running on a Graphical Processing Unit (GPU) processes the 3D reconstruction in real-time. As the camera system moves, new views of the scene are used to improve the model of the scene thanks to an incremental algorithm. Then, the performance of our approach is evaluated using a synthetic image sequence

This paper proposes a scheme for a 3D metric reconstruction of the environment of a mobile robot. We first introduce the advantages of a catadioptric stereovision sensor for autonomous navigation and how we have designed it with respect to the Single Viewpoint constraint. For applications such as path generation, the robot needs a metric reconstruction of its environment, so calibration of the sensor is required. After justification of the chosen model, a calibration method to obtain the model parameters and the relative pose of the two catadioptric sensors is presented. Knowledge of all the sensor parameters yields the 3D metric reconstruction of the environment by triangulation. Tools for calibration and relative pose estimation are presented and are available on the authorpsilas Web page. The entire process has been evaluated using real data.

International audience; A stereoscopic catadioptric sensor and associated algorithms are presented to provide a relevant solution to the problem of 3D reconstruction of unknown environments. A novel calibration methodology is detailed, establishing a discrete relation between 3D points and the corresponding pixels. The 3D reconstruction adopted is an adaptation of the classic volumetric scene reconstruction technique. Complete voxels are projected onto the image planes and consistency measurements are computed on pixel surfaces. To ensure fast processings, 3D/2D matchings are processed offline and results are stored in Look-Up Tables (LUT). Calibration results are given and 3D reconstruction algorithms are validated on synthetic images. Some results obtained for real scenes are provided.