Application of a Combined Active Control and Fault Detection Scheme to an Active Composite Flexible Structure.

In this paper, the problem of increasing reliability of active control procedure is considered. Indeed, a design method of rejection perturbation in presence of potentially faults, on a flexible structure with integrated piezo-ceramics, is presented. The piezo-ceramics are used as actuators and sensors. A single unit based solution, which handles both control action and fault diagnosis is proposed. The algorithm uses H∞ optimization techniques. A full order model of the structure is first obtained via both finite-element (FE) approach and identification procedure. This model is then reduced in order to be used in our robust approach. By a suitable choice of weightings functions, the provided method is able to reject disturbance robustly and to estimate occurred faults. The case of sensors and actuators faults is discussed. The choice of weightings for diagnosis and control systems is also tackled. Finally, the effectiveness of this integrated method is confirmed by both simulation and experimental results

An acoustic multi-touch sensing method using amplitude disturbed ultrasonic wave diffraction patterns

This paper proposes an acoustic multi-touch tactile sensing method. The proposed method is based on an amplitude disturbed ultrasonic wave diffraction pattern. An A0 Lamb wave transmitted in a thin finite copper plate is processed to provide tactile information, for one or two fingers. A touch event is localized by identifying the diffraction signals among a database of diffracted Lamb wave references. Statistic models are used to improve the localization reliability. An artificial silicone finger is used in the calibration procedure. This touch interface is evaluated as a 2-touch interface

1720-1721 : la peste ravage Toulon

Toulon connaît les épidémies depuis toujours : 1348, 1581, 1587, 1664. D’où la création de Bureaux de Santé à Marseille et Toulon, ce dernier dès 1576. Celui-ci instaura à Lagoubran – à l’ouest de Toulon –, un lazaret qui devait permettre de faire accoster les bateaux dans un abri jusqu’à la fin de leur mise « en quarantaine » ; néanmoins ce lazaret fut plus un mouroir qu’un établissement de soin. La peste de 1720-1721 le prouva. Début octobre 1720, les premiers cas de peste apparaissent à Toulon. Mi-octobre, les premiers morts. En février 1721, les morts remplissent un tombereau quotidien : cinquante places. En mars, deux tombereaux deviennent nécessaires pour évacuer les cadavres : cent morts par jour. La Marine organise son périmètre de sécurité et prend une décision originale puisqu’elle décide d’enfermer les « jeunes », c’est-à-dire les gardes de la marine au « Jardin du Roi ». Tous survivront à l’exception d’un Moscovite, envoyé à Toulon par Pierre le Grand, et imprudemment sorti du « Jardin du Roi ». En avril, quatre tombereaux quotidiens s’avèrent nécessaires : deux cent soixante et dix morts sont à déplorer pour le 30 avril. Début mai, huit tombereaux quotidiens deviennent indispensables : quatre cents morts quotidiens. L’épidémie culmine. En vain, on cherche des remèdes. On pend quelque galérien et quelques filles de joie pour tenter d’exorciser le mal. Ici, un capucin multiplie les prêches. Là, l’évêque de Toulon voue Toulon au Sacré-Coeur. Le 10 mai, la « serrade » est levée. Le 30 octobre, un Te Deum réunit les survivants : environ 10 000 habitants sur 25 000. La peste fut une vraie catastrophe ; démographique, culturelle, quantités de « savoirs » ayant été emportés. Toulon est au plus bas : le commerce ruiné, l’artisanat en déroute. La ruine est autant morale qu’économique. Il fallut attendre quarante années pour que la population toulonnaise « récupère » ses effectifs de 1720 décimés par la peste.Toulon has always experienced epidemics. Such was the case in 1348, 1581, 1587 and 1664 hence the setting up of boards of health in Marseilles and Toulon. The latter boasted one as early as 1576. A lazaretto was established in Lagoubran, west of Toulon. It was supposed to have allowed ships to berth in a shelter until their quarantine had come to an end but that lazaretto was more of a place where people were left to die than a medical care institution. The plague of 1720-1721 gave proof of it. In early October 1720, the first cases of plague appeared in Toulon. By mid October, there were the first dead. In February 1721 the dead filled a fifty-body tip cart on a daily basis. In March, two tip carts became necessary to get rid of corpses : one hundred people died every day. The Navy planned its safety zone and made an original decision since it decided to confine the “young ones”, that is the navy guards to “the King’s Garden”. All of them were to survive except for one Muscovite who had been sent to Toulon by Peter the Great and had recklessly left the “King’s Garden”. In April, four daily tip carts proved to be necessary: sadly, there were two hundred and seventy dead by April 30th. In early May, eight tip carts became indispensable: there were four hundred dead each day. The epidemic then reached its peak. Remedies were looked for but to no avail. A few galley slaves and a few ladies of the night were hanged to try and exorcize evil. Here, a Capuchin friar read repeated sermons. There, the Bishop of Toulon vowed Toulon to the Sacred Heart. On May 10th, the quarantine (“serrade”) was lifted. On October 30th, a Te Deum gathered the survivors: roughly 10 000 inhabitants out of 25 000. The plague was a real catastrophe both demographically and culturally speaking. A great deal of “know-how” had been taken away. Toulon was at a very low ebb: its trade was ruined; its crafts had collapsed. The ruin was both moral and economic. Forty years elapsed before the population of Toulon was able to recover the numbers of 1720 which had been decimated by the plague

La Corse enjeu géostratégique en Méditerranée et les marins Cap Corsins

La Corse a été tenue à l’écart des enjeux méditerranéens jusqu’au XVIe siècle. Par nature le Corse tourne le dos à la mer, sauf dans la région du Cap Corse grâce à l’existence des ports Centuri et Macinaggio. Les Corses présents dans l’histoire maritimes de l’île sont issus de cette région. Cet article analyse les vies de marins célèbres : Sampiero, Lenche, Negroni, etc., leurs activités tant militaires que commerciales, à Marseille et dans le monde musulman.Corsica has been kept out of the way of mediterranean stakes untill XVIth century. By nature Corsica turns its back to the sea except in the area of Corsica Cape owing to the existence of harbours as Centuri and Macinaggio. Corsicans present in the naval history of the island are descended from this place. This study shows us life of famous sailors : Sampiero, Lenche, Negroni... thier military activities so far as business relations, to Marseille and to the moslem world

Application of a Combined Active Control and Fault Detection Scheme to an Active Composite Flexible Structure.

In this paper, the problem of increasing reliability of active control procedure is considered. Indeed, a design method of rejection perturbation in presence of potentially faults, on a flexible structure with integrated piezo-ceramics, is presented. The piezo-ceramics are used as actuators and sensors. A single unit based solution, which handles both control action and fault diagnosis is proposed. The algorithm uses H∞ optimization techniques. A full order model of the structure is first obtained via both finite-element (FE) approach and identification procedure. This model is then reduced in order to be used in our robust approach. By a suitable choice of weightings functions, the provided method is able to reject disturbance robustly and to estimate occurred faults. The case of sensors and actuators faults is discussed. The choice of weightings for diagnosis and control systems is also tackled. Finally, the effectiveness of this integrated method is confirmed by both simulation and experimental results

An acoustic multi-touch sensing method using amplitude disturbed ultrasonic wave diffraction patterns

This paper proposes an acoustic multi-touch tactile sensing method. The proposed method is based on an amplitude disturbed ultrasonic wave diffraction pattern. An A0 Lamb wave transmitted in a thin finite copper plate is processed to provide tactile information, for one or two fingers. A touch event is localized by identifying the diffraction signals among a database of diffracted Lamb wave references. Statistic models are used to improve the localization reliability. An artificial silicone finger is used in the calibration procedure. This touch interface is evaluated as a 2-touch interface.International audienceThis paper proposes an acoustic multi-touch tactile sensing method. The proposed method is based on an amplitude disturbed ultrasonic wave diffraction pattern. An A0 Lamb wave transmitted in a thin finite copper plate is processed to provide tactile information, for one or two fingers. A touch event is localized by identifying the diffraction signals among a database of diffracted Lamb wave references. Statistic models are used to improve the localization reliability. An artificial silicone finger is used in the calibration procedure. This touch interface is evaluated as a 2-touch interface

Acoustic Wave Approach for Multi-Touch Tactile Sensing

International audienceIn this communication, we present a high resolution tactile plate that can localize one or two contact fingers. The localization principle is based on Lamb wave absorption. Fingers' contact will generate absorption signals while Lamb waves are propagating in a thin finite copper plate. These signals can be related to the contact positions and can be calibrated before the use of tactile plate. Fingers' contact positions are calculated by finding the closest calibration signal to the measured signal. Positions are carried out in less than 10 ms with a spatial resolution of 2 mm for one finger localization. Multi-points localization by this technology is developed and a two-point case is initialized and tested. Several optimization methods are also presented in this paper, as the double validation check which could improve the accuracy of single-point localization from 94.63% to 99.5%

Hardware-assisted software event tracing

Event tracing is a reliable and a low-intrusiveness method to debug and optimize systems and processes. Low overhead is particularly important in embedded systems where resources and energy consumption is critical. The most advanced tracing infrastructures achieve a very low footprint on the traced software, bringing each tracepoint overhead to less than a microsecond. To reduce this still non-negligible impact, the use of dedicated hardware resources is promising. In this paper, we propose complementary methods for tracing that rely on hardware modules to assist software tracing. We designed solutions to take advantage of CoreSight STM, CoreSight ETM, and Intel BTS, which are present on most newer ARM-based systems-on-chip and Intel x86 processors. Our results show that the time overhead for tracing can be reduced by up to 10 times when assisted by hardware, as compared to software tracing with LTTng, a high-performance tracer for Linux. We also propose a modification to the Perf tool to speed BTS execution tracing up to 65%

Modélisation pour l'ingénieur : approche par Bond Graph

National audienceLe travail des ingénieurs repose essentiellement sur la qualité des modèles. L’objet de cette présentation est de montrer qu’il existe une méthode systématique de conception du modèle d’une machine composée d’éléments pris dans le domaine de la mécanique ou de l’hydraulique ou de l’électricité, etc… Dans le cas des systèmes où la puissance se conserve, un outil approprié pour effectuer correctement une modélisation est le Bond Graph

Modélisation pour l'ingénieur : approche par Bond Graph

National audienceLe travail des ingénieurs repose essentiellement sur la qualité des modèles. L’objet de cette présentation est de montrer qu’il existe une méthode systématique de conception du modèle d’une machine composée d’éléments pris dans le domaine de la mécanique ou de l’hydraulique ou de l’électricité, etc… Dans le cas des systèmes où la puissance se conserve, un outil approprié pour effectuer correctement une modélisation est le Bond Graph