21 research outputs found

    Dexterous Grasping Tasks Generated With an Add-on End Effector of a Haptic Feedback System

    Get PDF
    The simulation of grasping operations in virtual reality (VR) is required for many applications, especially in the domain of industrial product design, but it is very difficult to achieve without any haptic feedback. Force feedback on the fingers can be provided by a hand exoskeleton, but such a device is very complex, invasive, and costly. In this paper, we present a new device, called HaptiHand, which provides position and force input as well as haptic output for four fingers in a noninvasive way, and is mounted on a standard force-feedback arm. The device incorporates four independent modules, one for each finger, inside an ergonomic shape, allowing the user to generate a wide range of virtual hand configurations to grasp naturally an object. It is also possible to reconfigure the virtual finger positions when holding an object. The paper explains how the device is used to control a virtual hand in order to perform dexterous grasping operations. The structure of the HaptiHand is described through the major technical solutions required and tests of key functions serve as validation process for some key requirements. Also, an effective grasping task illustrates some capabilities of the HaptiHand

    An add-on device to perform dexterous grasping tasks with a haptic feedback system

    Get PDF
    Achieving grasping tasks in real time with haptic feedback may require the control of a large number of degrees of freedom (DOFs) to model hand and finger movements. This is mandatory to grasp objects with dexterity. Here, a new device called HaptiHand is proposed that can be added to a haptic feedback arm and provide the user with enough DOFs so that he/she can intuitively and dexterously grasp an object, modify the virtual hand configuration and number of fingers with respect to the object while manipulating the object. Furthermore, this device is non-invasive and enables the user to apply forces on the fingers of the virtual hand. The HaptiHand lies inside the user’s hand so that the user can apply and release pressure on it in a natural manner that is transferred to the virtual hand using metaphors. The focus is placed on the description of the technology and structure of the HaptiHand to justify the choices and explain the behavior of the HaptiHand during object grasping and releasing tasks. This is combined with a short description of the models used.iLab Inria-Haptio

    A 3D Data Intensive Tele-immersive Grid

    Get PDF
    International audienceNetworked virtual environments like Second Life enable distant people to meet for leisure as well as work. But users are represented through avatars controlled by keyboards and mouses, leading to a low sense of presence especially regarding body language. Multi-camera real-time 3D modeling offers a way to ensure a significantly higher sense of presence. But producing quality geometries, well textured, and to enable distant user tele-presence in non trivial virtual environments is still a challenge today. In this paper we present a tele-immersive system based on multi-camera 3D modeling. Users from distant sites are immersed in a rich virtual environment served by a parallel terrain rendering engine. Distant users, present through their 3D model, can perform some local interactions while having a strong visual presence. We experimented our system between three large cities a few hundreds kilometers apart from each other. This work demonstrate the feasibility of a rich 3D multimedia environment ensuring users a strong sense of presence

    D3.8 Final version of the personalization and positioning software tool with documentation. PIPER EU Project

    Get PDF
    The aim of this report is to provide an overview of the final version of the PIPER framework and application. The software, along with its documentation, and not the report, constitutes the main part of the deliverable. The software and documentation were already distributed at the Final Workshop and online (under the Open Source license GPLv2 or later for the software, and the GNU FDL 1.3 license for the documentation). The documentation includes detailed descriptions of the framework principles, user interface, metadata, along with the modules and their parameters. It also includes application scenarios (called workflows). Information about the use of the modules is complemented by Tutorials that were developed as part of WP1 (online on the wiki) and explanatory videos were developed as part of WP4 (videos of the final workshop, now available on YouTube). The headers in the source code files (also available online) list the main contributors to the software. The report will therefore not provide details about information that is already available elsewhere but will only provide a very brief summary of the functionalities available. Some of the descriptions are excerpts of the manual

    Catchment-scale variability and driving factors of fine sediment deposition: insights from a coupled experimental and machine-learning-based modeling study

    No full text
    International audiencePurpose Fine sediment deposition is an important component of the catchment sediment budget and affects river morphology, biology, and contaminant transfer. However, the driving factors of fine sediment deposition remain poorly understood at the catchment scale, limiting our ability to model this process. Methods Fine sediment deposition and river reach characteristics were collected over the entire river network of three medium-sized (200-2200 km 2) temperate catchments, corresponding to 11,302 river reaches. This unique database was analyzed and used to develop and evaluate a random forest model. The model was used to predict sediment deposition and analyze its driving factors. Results Fine sediment deposition displayed a high spatial variability and a weak but significant relationship with the Strahler order and river reach width (Pearson coefficient r = −0.4 and 0.4, respectively), indicating the likely nonlinear influence of river reach characteristics. The random forest model predicted fine sediment deposition intensity with an accuracy of 81%, depending on the availability of training data. Bed substrate granularity, flow condition, reach depth and width, and the proportion of cropland and forest were the six most influential variables on fine sediment deposition intensity, suggesting the importance of both hillslope and within-river channel processes in controlling fine sediment deposition. Conclusion This study presented and analyzed a unique dataset. It also demonstrated the potential of random forest approaches to predict fine sediment deposition at the catchment scale. The proposed approach is complementary to measurements and process-based models. It may be useful for improving the understanding of sediment connectivity in catchments, the design of future measurement campaigns, and help prioritize areas to implement mitigation strategies

    D3.8 Final version of the personalization and positioning software tool with documentation. PIPER EU Project

    No full text
    The aim of this report is to provide an overview of the final version of the PIPER framework and application. The software, along with its documentation, and not the report, constitutes the main part of the deliverable. The software and documentation were already distributed at the Final Workshop and online (under the Open Source license GPLv2 or later for the software, and the GNU FDL 1.3 license for the documentation). The documentation includes detailed descriptions of the framework principles, user interface, metadata, along with the modules and their parameters. It also includes application scenarios (called workflows). Information about the use of the modules is complemented by Tutorials that were developed as part of WP1 (online on the wiki) and explanatory videos were developed as part of WP4 (videos of the final workshop, now available on YouTube). The headers in the source code files (also available online) list the main contributors to the software. The report will therefore not provide details about information that is already available elsewhere but will only provide a very brief summary of the functionalities available. Some of the descriptions are excerpts of the manual

    Ni gauche, ni droite

    No full text
    Cet ouvrage réunit les contributions de spécialistes allemands et français sur un sujet qui, depuis les ouvrages d’Armin Mohler (1948) et de Kurt Sontheimer (1962) en Allemagne, de Jean-Louis Loubet del ßayle (1967) en France, n’a cessé de retenir l’attention des historiens du second après-guerre : la recherche d’une "troisième voie" entre marxisme et libéralisme durant le premier après-guerre, les chassés-croisés Idéologiques et politiques qu’elle entraîne, le problème des rapports de cette pensée "ni gauche, ni droite", "conservatrice-révolutionnaire" ou "non-conformiste" avec le fascisme et le national-socialisme. L’originalité de ce recueil vient de ce qu’il pose les jalons d’une étude comparative mettant en évidence les convergences et les divergences de ces "idéologies de la crise" en Allemagne et en France, ainsi que les différentes médiations qui ont pu s’effectuer d’un pays à l’autre. A l’heure où en Europe les Idéologies sont de nouveau en crise, ces études présentent, à n’en pas douter, un intérêt qui n’est pas seulement historique
    corecore