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Herrera V.,Mahatma Jyotiba Phule Rohilkhand University | Herrera V.,University of the Basque Country | Milo A.,Mahatma Jyotiba Phule Rohilkhand University | Gaztanaga H.,Mahatma Jyotiba Phule Rohilkhand University | And 4 more authors.
Applied Energy | Year: 2016

In this paper an adaptive energy management strategy (EMS) based on fuzzy logic and the optimal sizing for a tramway with a hybrid energy storage system (ESS) combining batteries (BT) and supercapacitors (SC) are presented. The EMS applies a sliding window to estimate the forward energy consumption and adapt the instantaneous power target for BT and SC. The hybrid ESS sizing is obtained by an optimization with multi-objective genetic algorithms (GA). The fitness functions are expressed in economic terms, and correspond to the costs of the energy absorbed from the catenary as well as the operation cost of the hybrid ESS (investment and cycling cost). The selected case study is the tramway of Seville, which operates in zones with and without catenary. The aim is to minimize the daily operating cost of the tramway taking into account the BT and SC degradation approach (cycling) and fulfilling the performance of the tramway in the catenary-less zone. The proposed approach (adaptive EMS and optimal sizing) is compared with the current solution in the tramway (SC-based) and with a hybrid ESS managed by a rule-based EMS (RB-EMS) in terms of daily operating cost and energy harnessing during regenerative braking phase. The proposed approach show cost reductions up to 25.5% (from SC-based), 6.2% (from hybrid ESS with RB-EMS) and a global efficiency around 84.4%. © 2016 Elsevier Ltd. Source

Hugues O.,French Institute for Research in Computer Science and Automation | Cieutat J.-M.,ESTIA Research | Guitton P.,University of Bordeaux 1
Virtual Reality | Year: 2014

In this paper, we propose a method for real-time horizon tracking (i.e., separation line between the sky and the sea) in a maritime operations context. We present the fusion of an image processing algorithm with the data obtained from the inertial measurement unit (IMU). The initial aim is to filter out environmental conditions using inertial information in order to combine a video stream with onboard electronic charts. This is achieved by the detection of the horizon with an image processing algorithm in an area defined by the IMU. We then present an evaluation of the algorithm with regard to the rate of detection of the horizon and the impact of the image resolution on the computational time. The purpose of developing this method is to create an augmented reality maritime operations application. We combine the video stream with electronic charts in a single display. We use the position of the horizon in the image to split the display into different areas. Then, we use transparency to display the video, the electronic charts or both. © 2013 Springer-Verlag London. Source

Lafarge B.,ESTIA Research | Curea O.,ESTIA Research | Hacala A.,ESTIA Research | Camblong H.,University of the Basque Country
2014 1st International Conference on Green Energy, ICGE 2014 | Year: 2014

This paper proposes the theoretical analysis, design and simulation of an energy recovery system which has the potential to harvest energy from a linear movement such as, for example, the movement that occurs between the wheel and the body of a vehicle. The geometry of the proposed power harvesting system was planed in order to obtain a reliable device, thus enabling it to be integrated into a real vehicle or other industrial equipment. Simulation results (finite-elements method) show a good correlation with the theoretical study. Even if, for the moment, the amount of energy is small, this system is able to supply electrical energy for sensors or small embedded systems. Future work will be to improve the system's efficiency and develop an energy management system. © 2014 IEEE. Source

Camblong H.,University of the Basque Country | Camblong H.,ESTIA Research | Vechiu I.,ESTIA Research | Etxeberria A.,University of the Basque Country | And 2 more authors.
Control Engineering Practice | Year: 2014

The aim of the present research work has been to design an optimal MIMO LQG controller to reduce the drive-train, blades and tower mechanical stresses of a wind turbine (WT), and at the same time, to involve the WT in the grid primary frequency regulation when it is operating in full load (FL) zone. To verify the effectiveness of the proposed controller, the achieved results are compared to those obtained by a base-line controller based on a PI regulator.Simulation results show that thanks to these controllers, WT can effectively contribute to the grid frequency regulation, tracking tightly the generator power reference which depends on that frequency. Compared with the base-line controller, the LQG controller significantly reduces the mechanical stresses of the WTs most costly components. © 2014 Elsevier Ltd. Source

Reuter P.,University of Bordeaux Segalen | Reuter P.,French Institute for Research in Computer Science and Automation | Riviere G.,ESTIA Research | Couture N.,ESTIA Research | And 2 more authors.
Journal of Computing and Cultural Heritage | Year: 2010

ArcheoTUI is a new tangible user interface for the efficient assembly of the 3D scanned fragments of fractured archeological objects. An efficient user interaction for the complex task to orientate or position two 3D objects relative to each other is essential, eventually in addition to automatic matching techniques. Our key idea is to use tangible props for the manipulation of the virtual fragments. In each hand, the user manipulates an electromagnetically tracked prop, and the translations and rotations are directly mapped to the corresponding virtual fragments on the display. For each hand, a corresponding foot pedal is used to clutch the movements of the hands. Hence, the user's hands can be repositioned, or the user can be switched. The software of ArcheoTUI is designed to easily change assembly hypotheses, beyond classical undo/redo, by using a scene graph. We designed ArcheoTUI on the demand of archeaologists and in a direct collaboration with them, and we conducted two user studies on site at their workplace. The first user study revealed that the interface, and especially the foot pedal, was accepted, and that all the users managed to solve simple assembly tasks. In a second user study, we compare a different clutching mechanism with buttons on the props to the foot pedal mechanism. This second user study revealed that the movement of the hands is more similar to real-world assembly scenarios when using the foot pedals, and that the users can keep on concentrating on the actual assembly task. Finally, we show how the virtual assembly is used for a fractured archeological finding. © 2010 ACM. Source

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