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http://hdl.handle.net/10985/13596
Sat, 28 Mar 2020 17:03:52 GMT2020-03-28T17:03:52ZFree Hand-Based 3D Interaction in Optical See-Through Augmented Reality Using Leap Motion
http://hdl.handle.net/10985/14475
Free Hand-Based 3D Interaction in Optical See-Through Augmented Reality Using Leap Motion
ABABSA, Fakhreddine; HE, Junhui; CHARDONNET, Jean-Rémy
In augmented reality environments, the natural hand interaction between a virtual object and the user is a major issue to manipulate a rendered object in a convenient way. Microsoft’s HoloLens (Microsoft 2018) is an innovative augmented reality (AR) device that has provided an impressive experience for the user. However, the gesture interactions offered to the user are very limited. HoloLens currently recognizes two core component gestures: Air tap and Bloom. To solve this issue, we propose to integrate a Leap Motion Controller (LMC) within the HoloLens device (Figure 1). We thus used 3D hand and finger tracking provided by the LMC to propose new free hand-based interaction more natural and intuitive. We implemented three fully 3D techniques for selection, translation and rotation manipulation. In this work, we first investigated how to combine the two devices to get them working together in real time, and then we evaluated the proposed 3D hand interactions.
Mon, 01 Jan 2018 00:00:00 GMThttp://hdl.handle.net/10985/144752018-01-01T00:00:00ZABABSA, FakhreddineHE, JunhuiCHARDONNET, Jean-RémyIn augmented reality environments, the natural hand interaction between a virtual object and the user is a major issue to manipulate a rendered object in a convenient way. Microsoft’s HoloLens (Microsoft 2018) is an innovative augmented reality (AR) device that has provided an impressive experience for the user. However, the gesture interactions offered to the user are very limited. HoloLens currently recognizes two core component gestures: Air tap and Bloom. To solve this issue, we propose to integrate a Leap Motion Controller (LMC) within the HoloLens device (Figure 1). We thus used 3D hand and finger tracking provided by the LMC to propose new free hand-based interaction more natural and intuitive. We implemented three fully 3D techniques for selection, translation and rotation manipulation. In this work, we first investigated how to combine the two devices to get them working together in real time, and then we evaluated the proposed 3D hand interactions.3D Human Tracking with Catadioptric Omnidirectional Camera
http://hdl.handle.net/10985/16195
3D Human Tracking with Catadioptric Omnidirectional Camera
ABABSA, Fakhreddine; HADJ-ABDELKADER, Hicham; BOUI, Marouane
This paper deals with the problem of 3D human tracking in catadioptric images using particle-filtering framework. While traditional perspective images are well exploited, only a few methods have been developed for catadioptric vision, for the human detection or tracking problems. We propose to extend the 3D pose estimation in the case of perspective cameras to catadioptric sensors. In this paper, we develop an original likelihood functions based, on the one hand, on the geodetic distance in the spherical space SO3 and, on the other hand, on the mapping between the human silhouette in the images and the projected 3D model. These likelihood functions combined with a particle filter, whose propagation model is adapted to the spherical space, allow accurate 3D human tracking in omnidirectional images. Both visual and quantitative analysis of the experimental results demonstrate the effectiveness of our approach.
Tue, 01 Jan 2019 00:00:00 GMThttp://hdl.handle.net/10985/161952019-01-01T00:00:00ZABABSA, FakhreddineHADJ-ABDELKADER, HichamBOUI, MarouaneThis paper deals with the problem of 3D human tracking in catadioptric images using particle-filtering framework. While traditional perspective images are well exploited, only a few methods have been developed for catadioptric vision, for the human detection or tracking problems. We propose to extend the 3D pose estimation in the case of perspective cameras to catadioptric sensors. In this paper, we develop an original likelihood functions based, on the one hand, on the geodetic distance in the spherical space SO3 and, on the other hand, on the mapping between the human silhouette in the images and the projected 3D model. These likelihood functions combined with a particle filter, whose propagation model is adapted to the spherical space, allow accurate 3D human tracking in omnidirectional images. Both visual and quantitative analysis of the experimental results demonstrate the effectiveness of our approach.Vibration Analysis of Euler-Bernoulli Beams Partially Immersed in a Viscous Fluid
http://hdl.handle.net/10985/11185
Vibration Analysis of Euler-Bernoulli Beams Partially Immersed in a Viscous Fluid
ABASSI, Wafik; EL BAROUDI, Adil; RAZAFIMAHERY, Fulgence
The vibrational characteristics of a microbeam are well known to strongly depend on the fluid in which the beam is immersed. In this paper, we present a detailed theoretical study of the modal analysis of microbeams partially immersed in a viscous fluid. A fixed-free microbeamvibrating in a viscous fluid is modeled using the Euler-Bernoulli equation for the beams.The unsteady Stokes equations are solved using a Helmholtz decomposition technique in a two-dimensional plane containing the microbeams cross sections.The symbolic softwareMathematica is used in order to find the coupled vibration frequencies of beams with two portions. The frequency equation is deduced and analytically solved.The finite element method using ComsolMultiphysics software results is compared with present method for validation and an acceptable match between them was obtained. In the eigenanalysis, the frequency equation is generated by satisfying all boundary conditions. It is shown that the present formulation is an appropriate and new approach to tackle the problem with good accuracy.
Fri, 01 Jan 2016 00:00:00 GMThttp://hdl.handle.net/10985/111852016-01-01T00:00:00ZABASSI, WafikEL BAROUDI, AdilRAZAFIMAHERY, FulgenceThe vibrational characteristics of a microbeam are well known to strongly depend on the fluid in which the beam is immersed. In this paper, we present a detailed theoretical study of the modal analysis of microbeams partially immersed in a viscous fluid. A fixed-free microbeamvibrating in a viscous fluid is modeled using the Euler-Bernoulli equation for the beams.The unsteady Stokes equations are solved using a Helmholtz decomposition technique in a two-dimensional plane containing the microbeams cross sections.The symbolic softwareMathematica is used in order to find the coupled vibration frequencies of beams with two portions. The frequency equation is deduced and analytically solved.The finite element method using ComsolMultiphysics software results is compared with present method for validation and an acceptable match between them was obtained. In the eigenanalysis, the frequency equation is generated by satisfying all boundary conditions. It is shown that the present formulation is an appropriate and new approach to tackle the problem with good accuracy.Torsional Vibrations of Fluid-Filled Multilayered Transversely Isotropic Finite Circular Cylinder
http://hdl.handle.net/10985/11186
Torsional Vibrations of Fluid-Filled Multilayered Transversely Isotropic Finite Circular Cylinder
ABASSI, Wafik; EL BAROUDI, Adil; RAZAFIMAHERY, Fulgence
An analytical and numerical study for the torsional vibrations of viscous fluid-filled three-layer transversely isotropic cylinder is presented in this paper. The equations of motion of solid and fluid are respectively formulated using the constitutive equations of a transversely isotropic cylinder and the constitutive equations of a viscous fluid. The analytical solution of the frequency equation is obtained using the boundary conditions at the free surface of the solid layer and the boundary conditions at the fluid–solid interface. The frequency equation is deduced and analytically solved using the symbolic Software Mathematica. The finite element method using Comsol Multiphysics Software results are compared with present method for validation and an acceptable match between them were obtained. It is shown that the results from the proposed method are in good agreement with numerical solutions. The influence of fluid dynamic viscosity is thoroughly analyzed and the effect of the isotropic properties on the natural frequencies is also investigated.
Fri, 01 Jan 2016 00:00:00 GMThttp://hdl.handle.net/10985/111862016-01-01T00:00:00ZABASSI, WafikEL BAROUDI, AdilRAZAFIMAHERY, FulgenceAn analytical and numerical study for the torsional vibrations of viscous fluid-filled three-layer transversely isotropic cylinder is presented in this paper. The equations of motion of solid and fluid are respectively formulated using the constitutive equations of a transversely isotropic cylinder and the constitutive equations of a viscous fluid. The analytical solution of the frequency equation is obtained using the boundary conditions at the free surface of the solid layer and the boundary conditions at the fluid–solid interface. The frequency equation is deduced and analytically solved using the symbolic Software Mathematica. The finite element method using Comsol Multiphysics Software results are compared with present method for validation and an acceptable match between them were obtained. It is shown that the results from the proposed method are in good agreement with numerical solutions. The influence of fluid dynamic viscosity is thoroughly analyzed and the effect of the isotropic properties on the natural frequencies is also investigated.Comparaison des actionneurs
http://hdl.handle.net/10985/9238
Comparaison des actionneurs
ABBA, Gabriel
Les objectifs de ce rapport sont donc multiples. En premier, le rapport établie la méthodologie de sélection des actionneurs d’un robot en fonction d’un ou plusieurs critères à satisfaire tout en respectant les contraintes nécessaires au bon fonctionnement du robot, contraintes elles mêmes liées très fortement aux performances dynamiques exigées du robot et aux différentes tâches auxquelles le robot est destiné. Il est facile de montrer que la sélection des actionneurs est fortement liée aux choix technologiques des dispositifs de transmission des mouvements et de la technologie même desdits actionneurs. Le second objectif du rapport est par conséquent d’élaborer une méthode de sélection couplée des actionneurs et des transmissions. Pour se faire, nous limitons délibérément les choix à certaines technologies. Enfin, le dernier objectif du rapport est de proposer un modèle physique approché mais néanmoins le plus précis possible du comportement énergétique de l’ensemble de la chaîne de transmission des mouvements et donc un modèle énergétique des actionneurs, des transmissions cinématiques jusqu’aux variables articulaires du robot.
Sun, 01 Jan 2012 00:00:00 GMThttp://hdl.handle.net/10985/92382012-01-01T00:00:00ZABBA, GabrielLes objectifs de ce rapport sont donc multiples. En premier, le rapport établie la méthodologie de sélection des actionneurs d’un robot en fonction d’un ou plusieurs critères à satisfaire tout en respectant les contraintes nécessaires au bon fonctionnement du robot, contraintes elles mêmes liées très fortement aux performances dynamiques exigées du robot et aux différentes tâches auxquelles le robot est destiné. Il est facile de montrer que la sélection des actionneurs est fortement liée aux choix technologiques des dispositifs de transmission des mouvements et de la technologie même desdits actionneurs. Le second objectif du rapport est par conséquent d’élaborer une méthode de sélection couplée des actionneurs et des transmissions. Pour se faire, nous limitons délibérément les choix à certaines technologies. Enfin, le dernier objectif du rapport est de proposer un modèle physique approché mais néanmoins le plus précis possible du comportement énergétique de l’ensemble de la chaîne de transmission des mouvements et donc un modèle énergétique des actionneurs, des transmissions cinématiques jusqu’aux variables articulaires du robot.Design Elements for high speed SRM
http://hdl.handle.net/10985/11995
Design Elements for high speed SRM
ABBA, Gabriel; ANTOINE, Jean-François; SAUVEY, Christophe; VISA, Codrut
This paper deals with the study of high speed switched reluctance motors and their pre-dimensioning. The predimensioning is tackled towards the inductance profile and the torque generation. Then, the power density is assessed in terms of three defined fundamental parameters, each depending on electrical, mechanical and geometrical design of the motor. The mechanical limitations studied are the centrifugal stresses and the vibratory behavior of the motor. A shape optimization of the rotor teeth leans then on a coupled magnetic-mechanic coupled problem, solved with finite elements simulations. After that,mechanic, magnetic and copper losses are given in terms of the rotor external volume so as to assess the weight of each heat source in the global motor heating. Once all the losses are linked to temperature, a criterion to improve the ability to develop a high speed motor is finally proposed.
Thu, 01 Jan 2004 00:00:00 GMThttp://hdl.handle.net/10985/119952004-01-01T00:00:00ZABBA, GabrielANTOINE, Jean-FrançoisSAUVEY, ChristopheVISA, CodrutThis paper deals with the study of high speed switched reluctance motors and their pre-dimensioning. The predimensioning is tackled towards the inductance profile and the torque generation. Then, the power density is assessed in terms of three defined fundamental parameters, each depending on electrical, mechanical and geometrical design of the motor. The mechanical limitations studied are the centrifugal stresses and the vibratory behavior of the motor. A shape optimization of the rotor teeth leans then on a coupled magnetic-mechanic coupled problem, solved with finite elements simulations. After that,mechanic, magnetic and copper losses are given in terms of the rotor external volume so as to assess the weight of each heat source in the global motor heating. Once all the losses are linked to temperature, a criterion to improve the ability to develop a high speed motor is finally proposed.A numerical approach of two-phase non-Darcy flow in heterogeneous porous media
http://hdl.handle.net/10985/9982
A numerical approach of two-phase non-Darcy flow in heterogeneous porous media
ABBASIAN ARANI, Ali Akbar; AHMADI-SENICHAULT, Azita; LASSEUX, Didier
Significant inertial effects are observed for many applications such as flow in the near-wellbore region, in very permeable reservoirs or in packed-bed reactors. In these cases, the classical description of two-phase flow in porous media by the generalized Darcy's law is no longer valid. Due to the lack of a formalized theoretical model confirmed experimentally, our study is based on a generalized Darcy-Forchheimer approach for modelling two-phase incompressible inertial flow in porous media. Using a finite volume formulation, an IMPES (IMplicit for Pressures, Explicit for Saturations) scheme and a Fixed Point method for the treatment of non-linearities caused by inertia, a 3D numerical tool has been developed. For 1D flow in a homogeneous porous medium, comparison of saturation profiles obtained numerically at different times to those obtained semi-analytically using an “Inertial Buckley-Leverett model” allows a validation of the tool. The influence of inertial effects on the saturation profiles and therefore on the breakthrough curves for homogeneous media is analysed for different Reynolds numbers, thus emphasizing the necessity of taking into account this additional energy loss when necessary. For 1D heterogeneous configurations, a thorough analysis of the saturation fronts as well as the saturation jumps at the interface between two media of contrasted properties highlights the influence of inertial effects for different Reynolds and capillary numbers. In 2D heterogeneous configurations, saturation distributions are strongly affected by inertial effects. In particular, capillary trapping of the displaced fluid observed for the Darcy regime in certain regions can completely disappears when inertial effects become dominant.
Thu, 01 Jan 2009 00:00:00 GMThttp://hdl.handle.net/10985/99822009-01-01T00:00:00ZABBASIAN ARANI, Ali AkbarAHMADI-SENICHAULT, AzitaLASSEUX, DidierSignificant inertial effects are observed for many applications such as flow in the near-wellbore region, in very permeable reservoirs or in packed-bed reactors. In these cases, the classical description of two-phase flow in porous media by the generalized Darcy's law is no longer valid. Due to the lack of a formalized theoretical model confirmed experimentally, our study is based on a generalized Darcy-Forchheimer approach for modelling two-phase incompressible inertial flow in porous media. Using a finite volume formulation, an IMPES (IMplicit for Pressures, Explicit for Saturations) scheme and a Fixed Point method for the treatment of non-linearities caused by inertia, a 3D numerical tool has been developed. For 1D flow in a homogeneous porous medium, comparison of saturation profiles obtained numerically at different times to those obtained semi-analytically using an “Inertial Buckley-Leverett model” allows a validation of the tool. The influence of inertial effects on the saturation profiles and therefore on the breakthrough curves for homogeneous media is analysed for different Reynolds numbers, thus emphasizing the necessity of taking into account this additional energy loss when necessary. For 1D heterogeneous configurations, a thorough analysis of the saturation fronts as well as the saturation jumps at the interface between two media of contrasted properties highlights the influence of inertial effects for different Reynolds and capillary numbers. In 2D heterogeneous configurations, saturation distributions are strongly affected by inertial effects. In particular, capillary trapping of the displaced fluid observed for the Darcy regime in certain regions can completely disappears when inertial effects become dominant.Derivation of a macroscopic model for two-phase non-Darcy flow in homogeneous porous media using volume averaging
http://hdl.handle.net/10985/9981
Derivation of a macroscopic model for two-phase non-Darcy flow in homogeneous porous media using volume averaging
ABBASIAN ARANI, Ali Akbar; LASSEUX, Didier; AHMADI-SENICHAULT, Azita
The purpose of this work is to propose a derivation of a macroscopic model for a certain class of inertial two-phase, incompressible, Newtonian fluid flow through homogenous porous media. The starting point of the procedure is the pore-scale boundary value problem given by the continuity and Navier–Stokes equations in each phase β and γ along with boundary conditions at interfaces. The method of volume averaging is employed subjected to a series of constraints for the development to hold. These constraints are on the length- and time-scales, as well as, on some quantities involving capillary, Weber and Reynolds numbers that define the class of two-phase flow under consideration. The development also assumes that fluctuations of the curvature of the fluid–fluid interfaces are unimportant over the unit cell representing the porous medium. Under these circumstances, the resulting macroscopic momentum equation, for the -phase (=, ) relates the gradient of the phase-averaged pressure to the filtration or Darcy velocity in a coupled nonlinear form. All tensors appearing in the macroscopic equation can be determined from closure problems that are to be solved using a spatially periodic model of a porous medium. Some indications to compute these tensors are provided.
Thu, 01 Jan 2009 00:00:00 GMThttp://hdl.handle.net/10985/99812009-01-01T00:00:00ZABBASIAN ARANI, Ali AkbarLASSEUX, DidierAHMADI-SENICHAULT, AzitaThe purpose of this work is to propose a derivation of a macroscopic model for a certain class of inertial two-phase, incompressible, Newtonian fluid flow through homogenous porous media. The starting point of the procedure is the pore-scale boundary value problem given by the continuity and Navier–Stokes equations in each phase β and γ along with boundary conditions at interfaces. The method of volume averaging is employed subjected to a series of constraints for the development to hold. These constraints are on the length- and time-scales, as well as, on some quantities involving capillary, Weber and Reynolds numbers that define the class of two-phase flow under consideration. The development also assumes that fluctuations of the curvature of the fluid–fluid interfaces are unimportant over the unit cell representing the porous medium. Under these circumstances, the resulting macroscopic momentum equation, for the -phase (=, ) relates the gradient of the phase-averaged pressure to the filtration or Darcy velocity in a coupled nonlinear form. All tensors appearing in the macroscopic equation can be determined from closure problems that are to be solved using a spatially periodic model of a porous medium. Some indications to compute these tensors are provided.Résolution numérique de l’écoulement diphasique en milieu poreux hétérogène incluant les effets inertiels
http://hdl.handle.net/10985/10029
Résolution numérique de l’écoulement diphasique en milieu poreux hétérogène incluant les effets inertiels
ABBASIAN ARANI, Ali Akbar; LASSEUX, Didier; AHMADI-SENICHAULT, Azita
La mise en place d'un outil numérique 3D de simulation d'écoulement diphasique hors régime de Darcy basé sur le modèle de Darcy-Forchheimer généralisé est présentée. L'outil est tout d’abord validé à l’aide d'une solution semi analytique 1D de type Buckley-Leverett. Des résultats obtenus dans différentes configurations homogène et hétérogènes 1D et 2D mettent en évidence l'importance des termes inertiels en fonction d'un nombre de Reynolds de l'écoulement.
Mon, 01 Jan 2007 00:00:00 GMThttp://hdl.handle.net/10985/100292007-01-01T00:00:00ZABBASIAN ARANI, Ali AkbarLASSEUX, DidierAHMADI-SENICHAULT, AzitaLa mise en place d'un outil numérique 3D de simulation d'écoulement diphasique hors régime de Darcy basé sur le modèle de Darcy-Forchheimer généralisé est présentée. L'outil est tout d’abord validé à l’aide d'une solution semi analytique 1D de type Buckley-Leverett. Des résultats obtenus dans différentes configurations homogène et hétérogènes 1D et 2D mettent en évidence l'importance des termes inertiels en fonction d'un nombre de Reynolds de l'écoulement.A numerical analysis of the inertial correction to Darcy's law
http://hdl.handle.net/10985/9980
A numerical analysis of the inertial correction to Darcy's law
ABBASIAN ARANI, Ali Akbar; LASSEUX, Didier; AHMADI-SENICHAULT, Azita
Our interest in this work is the stationary one-phase Newtonian flow in a class of homogeneous porous media at large enough flow rates so that the relationship between the filtration velocity and the pressure gradient is no longer linear. The non linear -inertial- correction to Darcy's law is investigated from a numerical point of view on model periodic structures made of regular arrays of cylinders. The starting point of the analysis is the macroscopic model resulting from the volume averaging of the mass and momentum (Navier-Stokes) equations at the pore scale. Identification of the macroscopic properties in this model is made by first solving the microscopic flow as well as the closure problem resulting from the upscaling. From these solutions, the inertial correction is computed and analyzed with respect to the Reynolds number and the pressure gradient orientation relative to the principal axes of the periodic unit cell.
Thu, 01 Jan 2009 00:00:00 GMThttp://hdl.handle.net/10985/99802009-01-01T00:00:00ZABBASIAN ARANI, Ali AkbarLASSEUX, DidierAHMADI-SENICHAULT, AzitaOur interest in this work is the stationary one-phase Newtonian flow in a class of homogeneous porous media at large enough flow rates so that the relationship between the filtration velocity and the pressure gradient is no longer linear. The non linear -inertial- correction to Darcy's law is investigated from a numerical point of view on model periodic structures made of regular arrays of cylinders. The starting point of the analysis is the macroscopic model resulting from the volume averaging of the mass and momentum (Navier-Stokes) equations at the pore scale. Identification of the macroscopic properties in this model is made by first solving the microscopic flow as well as the closure problem resulting from the upscaling. From these solutions, the inertial correction is computed and analyzed with respect to the Reynolds number and the pressure gradient orientation relative to the principal axes of the periodic unit cell.