Understanding user gestures for manipulating 3D objects from touchscreen inputs

International audienceMulti-touch interfaces have emerged with the widespread use of smartphones. Although a lot of people interact with 2D applications through touchscreens, interaction with 3D applications remains little explored. Most of 3D object manipulation techniques have been created by designers and users are generally put aside from the design creation process. We conducted a user study to better understand how non-technical users interact with a 3D object from touchscreen inputs. The experiment has been conducted while users manipulated a 3D cube with three points of view for rotations, scaling and translations (RST). Sixteen users participated and 432 gestures were analyzed. To classify data, we introduce a taxonomy for 3D manipulation gestures with touchscreens. Then, we identify a set of strategies employed by users to realize the proposed cube transformations. Our findings suggest that each participant uses several strategies with a predominant one. Finally, we propose some guidelines to help designers in the creation of more user friendly tools.Les interfaces multi-touch ont émergé avec l'augmentation de l'utilisation des smartphones. Bien que beaucoup de personne interagissent avec des applications 2D via des écrans tactiles, l'interaction avec des applications 3D reste peu explorée. La plupart des techniques de manipulation d'objets 3D ont été créé par des concepteurs et les utilisateurs sont généralement mis à l'écart du procédé de création. Nous avons conduit une étude utilisateur afin de mieux comprendre comment les utilisateurs novices interagissent avec un objet 3D depuis un écran tactiles. L'expérience a été réalisée sur la manipulation d'un cube 3D, selon trois points de vue et trois types de transformations (rotations, changements d'échelle et translations). Seize utilisateurs ont participé et 432 gestes ont été analysés. Afin de classifier les données, nous avons introduit une taxonomie pour les gestes de manipulation 3D réalisés sur écrans tactile. Ensuite, nous avons identifié un ensemble de stratégies employées par les utilisateurs pour réaliser les transformations proposées sur le cube. Nos résultats suggère que chaque participant a utilisé plusieurs stratégies avec une prédominante pour chaque type de transformation. Finalement, nous avons proposé des indications pour aider les designers dans la création d'outils plus adaptés aux utilisateurs

tBox: A 3D Transformation Widget designed for Touch-screens

International audience3D transformation widgets are commonly used in many 3D applications operated from mice and keyboards. These user interfaces allow independent control of translations, rotations, and scaling for manipulation of 3D objects. In this paper, we study how these widgets can be adapted to the tactile paradigm. We have explored an approach where users apply rotations by means of physically plausible gestures, and we have extended successful 2D tactile principles to the context of 3D interaction. These investigations led to the design of a new 3D transformation widget, tBox, that can been operated easily and efficiently from gestures on touch-screens

Toucheo: Multitouch and Stereo Combined in a Seamless Workspace.

International audienceWe propose a new system that efficiently combines direct multitouch interaction with co-located 3D stereoscopic visualization. In our approach, users benefit from well-known 2D metaphors and widgets displayed on a monoscopic touchscreen, while visualizing occlusion-free 3D objects floating above the surface at an optically correct distance. Technically, a horizontal semi-transparent mirror is used to reflect 3D images produced by a stereoscopic screen, while the user's hand as well as a multitouch screen located below this mirror remain visible. By registering the 3D virtual space and the physical space, we produce a rich and unified workspace where users benefit simultaneously from the advantages of both direct and indirect interaction, and from 2D and 3D visualizations. A pilot usability study shows that this combination of technology provides a good user experience

Manipulation de contenu 3D sur des surfaces tactiles

Since the emergence of tactile surfaces in recent years, the general public uses them every day for multiple tasks, such as checking email, photo manipulation, and so on. However, very few 3D applications on these devices exist, although such applications may have great potential in various fields, such as culture, architecture, or archeology. The major difficulty for such applications is to interact with a defined space in three dimensions from an interaction modality defined in two dimensions. Work in this thesis explores the association between tactile surfaces and manipulation of 3D content for the general public. The first studies were conducted to understand how the user tends to manipulate a 3D virtual object with a touch surface without imposing specific interaction techniques. Throughout knowledge gained by users, the following works are developing new interaction techniques and their evaluation.Les surfaces tactiles ayant connu un grand essor ces dernières années, le grand public les utilise quotidiennement pour de multiples tâches, telles que la consultation d'e-mail, la manipulation de photos, etc. En revanche, très peu d'applications 3D existent sur ces dispositifs, alors que de telles applications pourraient avoir un grand potentiel dans des domaines variés, telles que la culture, l'architecture, ou encore l'archéologie. La difficulté majeure pour ce type d'applications est d'interagir avec un espace défini en trois dimensions à partir d'une modalité d'interaction définie en deux dimensions. Les travaux effectués dans cette thèse explorent l'association entre surfaces tactiles et manipulation de contenu 3D pour le grand public. Les premières études ont été réalisées afin de comprendre comment l'utilisateur réagit pour manipuler un objet virtuel 3D avec une surface tactile sans lui imposer de techniques d'interaction particulières. De par les connaissances acquises sur les utilisateurs, les travaux suivants présentent l'élaboration de nouvelles techniques d'interaction ainsi que leur évaluation

Manipulation de contenu 3D sur des surfaces tactiles

Les surfaces tactiles ayant connu un grand essor ces dernières années, le grand public les utilise quotidiennement pour de multiples tâches, telles que la consultation d'e-mail, la manipulation de photos, etc. En revanche, très peu d'applications 3D existent sur ces dispositifs, alors que de telles applications pourraient avoir un grand potentiel dans des domaines variés, telles que la culture, l'architecture, ou encore l'archéologie. La difficulté majeure pour ce type d'applications est d'interagir avec un espace défini en trois dimensions à partir d'une modalité d'interaction définie en deux dimensions. Les travaux effectués dans cette thèse explorent l'association entre surfaces tactiles et manipulation de contenu 3D pour le grand public. Les premières études ont été réalisées afin de comprendre comment l'utilisateur réagit pour manipuler un objet virtuel 3D avec une surface tactile sans lui imposer de techniques d'interaction particulières. De par les connaissances acquises sur les utilisateurs, les travaux suivants présentent l'élaboration de nouvelles techniques d'interaction ainsi que leur évaluation.Since the emergence of tactile surfaces in recent years, the general public uses them every day for multiple tasks, such as checking email, photo manipulation, and so on. However, very few 3D applications on these devices exist, although such applications may have great potential in various fields, such as culture, architecture, or archeology. The major difficulty for such applications is to interact with a defined space in three dimensions from an interaction modality defined in two dimensions. Work in this thesis explores the association between tactile surfaces and manipulation of 3D content for the general public. The first studies were conducted to understand how the user tends to manipulate a 3D virtual object with a touch surface without imposing specific interaction techniques. Throughout knowledge gained by users, the following works are developing new interaction techniques and their evaluation

Manipulation de contenu 3D sur des surfaces tactiles

Since the emergence of tactile surfaces in recent years, the general public uses them every day for multiple tasks, such as checking email, photo manipulation, and so on. However, very few 3D applications on these devices exist, although such applications may have great potential in various fields, such as culture, architecture, or archeology. The major difficulty for such applications is to interact with a defined space in three dimensions from an interaction modality defined in two dimensions. Work in this thesis explores the association between tactile surfaces and manipulation of 3D content for the general public. The first studies were conducted to understand how the user tends to manipulate a 3D virtual object with a touch surface without imposing specific interaction techniques. Throughout knowledge gained by users, the following works are developing new interaction techniques and their evaluation.Les surfaces tactiles ayant connu un grand essor ces dernières années, le grand public les utilise quotidiennement pour de multiples tâches, telles que la consultation d'e-mail, la manipulation de photos, etc. En revanche, très peu d'applications 3D existent sur ces dispositifs, alors que de telles applications pourraient avoir un grand potentiel dans des domaines variés, telles que la culture, l'architecture, ou encore l'archéologie. La difficulté majeure pour ce type d'applications est d'interagir avec un espace défini en trois dimensions à partir d'une modalité d'interaction définie en deux dimensions. Les travaux effectués dans cette thèse explorent l'association entre surfaces tactiles et manipulation de contenu 3D pour le grand public. Les premières études ont été réalisées afin de comprendre comment l'utilisateur réagit pour manipuler un objet virtuel 3D avec une surface tactile sans lui imposer de techniques d'interaction particulières. De par les connaissances acquises sur les utilisateurs, les travaux suivants présentent l'élaboration de nouvelles techniques d'interaction ainsi que leur évaluation

Manipulation de contenu 3D sur des surfaces tactiles

Les surfaces tactiles ayant connu un grand essor ces dernières années, le grand public les utilise quotidiennement pour de multiples tâches, telles que la consultation d'e-mail, la manipulation de photos, etc. En revanche, très peu d'applications 3D existent sur ces dispositifs, alors que de telles applications pourraient avoir un grand potentiel dans des domaines variés, telles que la culture, l'architecture, ou encore l'archéologie. La difficulté majeure pour ce type d'applications est d'interagir avec un espace défini en trois dimensions à partir d'une modalité d'interaction définie en deux dimensions. Les travaux effectués dans cette thèse explorent l'association entre surfaces tactiles et manipulation de contenu 3D pour le grand public. Les premières études ont été réalisées afin de comprendre comment l'utilisateur réagit pour manipuler un objet virtuel 3D avec une surface tactile sans lui imposer de techniques d'interaction particulières. De par les connaissances acquises sur les utilisateurs, les travaux suivants présentent l'élaboration de nouvelles techniques d'interaction ainsi que leur évaluation.Since the emergence of tactile surfaces in recent years, the general public uses them every day for multiple tasks, such as checking email, photo manipulation, and so on. However, very few 3D applications on these devices exist, although such applications may have great potential in various fields, such as culture, architecture, or archeology. The major difficulty for such applications is to interact with a defined space in three dimensions from an interaction modality defined in two dimensions. Work in this thesis explores the association between tactile surfaces and manipulation of 3D content for the general public. The first studies were conducted to understand how the user tends to manipulate a 3D virtual object with a touch surface without imposing specific interaction techniques. Throughout knowledge gained by users, the following works are developing new interaction techniques and their evaluation

Beyond the mouse: Understanding user gestures for manipulating 3D objects from touchscreen inputs

International audienceMulti-touch interfaces have emerged with the widespread use of smartphones. Although a lot of people interact with 2D applications through touchscreens, interaction with 3D applications remains little explored. Most 3D object manipulation techniques have been created by designers who have generally put users aside from the design creation process. We conducted a user study to better understand how non-technical users tend to interact with a 3D object from touchscreen inputs. The experiment has been conducted while users were manipulating a 3D cube with three viewpoints for rotations, scaling and translations (RST). Sixteen users participated and 432 gestures were analyzed. To classify data, we introduce a taxonomy for 3D manipulation gestures with touchscreens. Then, we identify a set of strategies employed by users to perform the proposed cube transformations. Our findings suggest that each participant uses several strategies with a predominant one. Furthermore, we conducted a study to compare touchscreen and mouse interaction for 3D object manipulations. The results suggest that gestures are different according to the device, and touchscreens are preferred for the proposed tasks. Finally, we propose some guidelines to help designers in the creation of more user friendly tools

CO2 addition and pressure effects on laminar and turbulent lean premixed CH4 air flames

International audienceAn experimental study on CH4–CO2–air flames at various pressures is conducted by using both laminar and turbulent Bunsen flame configurations. The aim of this research is to contribute to the characterization of fuel lean methane/carbon dioxide/air premixed laminar and turbulent flames at different pressures, by studying laminar and turbulent flame propagation velocities, the flame surface density and the instantaneous flame front wrinkling parameters. PREMIX computations and experimental results indicate a decrease of the laminar flame propagation velocities with increasing CO2 dilution rate. Instantaneous flame images are obtained by Mie scattering tomography. The image analysis shows that although the height of the turbulent flame increases with the CO2 addition rate, the flame structure is quite similar. This implies that the flame wrinkling parameters and flame surface density are indifferent to the CO2 addition. However, the pressure increase has a drastic effect on both parameters. This is also confirmed by a fractal analysis of instantaneous images. It is also observed that the combustion intensity ST/SL increases both withpressure and the CO2 rate. Finally, the mean fuel consumption rate decreases with the CO2 addition rate but increases with the pressure