- Allauch, Provence-Alpes-Cote d'Azur, France
Daniel Mestre
Aix-Marseille University, Life sciences, Faculty Member
- Life Sciences, Virtual Reality (Computer Graphics), Immersion, 3D manipulation virtual encironments, Distant Collaboration, Street Crossing Optic Flow, and 19 moreAffordances Virtual Reality, Computer Science, Human Computer Interaction, Computer Graphics, Augmented Reality, Virtual Worlds, Visualization, Virtual Learning, Visual perception, Information Visualization, Virtual Environments, Haptics, Depth Perception, Women in Computing, Virtual Reality, Educational Virtual Environments, Collaborative Virtual Environments, Avatars, and Immersive Virtual Learning Environmentedit
The main objective of this study is to improve maintenance activities using mixed reality. Co-design work with Support Engineers was undertaken to develop a mixed reality solution that corresponded to the different needs of task... more
The main objective of this study is to improve maintenance activities using mixed reality. Co-design work with Support Engineers was undertaken to develop a mixed reality solution that corresponded to the different needs of task sequencing feasibility. Multiple versions of the solution were tested using Microsoft HoloLens hardware to achieve continuous improvement. The study compared the two latest versions of the solution: the CAD version and the PHYS version. The CAD version was an immersive version inspired by CATIA CAD software, while the PHYS version implemented a realistic approach to parts handling (including gravity, continuous presence, and spatial organization of physical parts on a real table). Support Engineers carried out an experiment, performing a disassembly/assembly task using both versions of the solution. Results showed that the overall workload was significantly reduced, along with task completion time, using the PHYS solution. The PHYS version was also judged to be more usable than the CAD version. Adding 'pseudo-natural' manipulation of virtual objects to a maintenance task simulation better suits the needs of Support Engineers.
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A great deal of research today is concerned with the study of the cognitive processes involved in the realization of spatial displacements. In this article, we will analyze how the introduction of interfaces affects the conditions in... more
A great deal of research today is concerned with the study of the cognitive processes involved in the realization of spatial displacements. In this article, we will analyze how the introduction of interfaces affects the conditions in which a displacement is produced and controlled. We will attempt to show that as the situation becomes less and less natural, the already important role played by visual information increases and the ways in which visual information is presented on the interfaces change as the modalities increase in number. Our discussion will not only be supported by fundamental and applied research on the mental representation of space and the visual control of displacement, but also by the few available studies on tele-operated situations.
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Research Interests: Computer Science, Computer Graphics, Computational Modeling, Information Visualization, Automata, and 15 moreCellular Automata, Theoretical Computer Science, Information Visualisation, Boolean Algebra, Proceedings, Data Visualisation, Gpu programming, Real Time, Computer Graphic, Encoding, Emergent Behavior, Higher Dimensions, Multi Dimensional, Multidimensional Systems, and Cellular automaton
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Research Interests: Computer Science, Parallel Computing, Visualization, Rendering (Computer Graphics), Computational Science, and 15 moreCellular Automata, Digital imaging, Real-time rendering, OPERATING SYSTEM, Information Flow, Computation, Graphics, Real Time, Grid, Emergent Behavior, Large Data Sets, Cellular automaton, Graphics processing unit, Springer Ebooks, and Graphics processor unit
We herein report an experimental study examining the potential positive effects of Virtual Reality (VR) feedback during an indoor bicycling exercise. Using a regular bike coupled to a VR system, we compared conditions of no VR feedback,... more
We herein report an experimental study examining the potential positive effects of Virtual Reality (VR) feedback during an indoor bicycling exercise. Using a regular bike coupled to a VR system, we compared conditions of no VR feedback, VR feedback and VR feedback with the presence of a virtual coach, acting as a pacer. In VR feedback conditions, we observed a decreased level of perceived exertion and an increased level of enjoyment of physical activity, when compared to a regular exercise situation (no VR feedback). We also observed a shift in the subjects' attentional focus, from association (in the absence of VR feedback) to dissociation (in VR feedback conditions). Moreover, the presence of a virtual coach in the VR environment triggered a systematic regulation of the (virtual) displacement speed, whose relationship with perceived enjoyment and exertion require further work.
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The present work highlights current developments and an ongoing experimental evaluation of how a tablet PC can effectively act as an interaction device for 3D manipulation tasks. More specifically, we focused on a 3D docking task. This... more
The present work highlights current developments and an ongoing experimental evaluation of how a tablet PC can effectively act as an interaction device for 3D manipulation tasks. More specifically, we focused on a 3D docking task. This collaborative project was conducted within the Visionair European project. The goal was to design a versatile interface that was independent of the targeted VR system (from 2D screens to CAVE-like systems). We investigated the usability of tactile (i.e. finger-controlled) tablets that are omnipresent in our daily life, assumed to have intuitive control characteristics and easily connected to a VR system (via WIFI connections). Participants' performance was evaluated when using a tablet, as compared to a classical mouse interface. Results indicated comparable learning effects (with task repetition) for both devices, but a clear advantage of the tablet's interface, as concerns the simultaneous use of multiple degrees of freedom of motion of the manipulated object.
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ABSTRACT The main contribution of this paper to the Cognitive Ergonomics field is to propose a new approach of the behavioral validity's assessment of driving simulators. In this paper, our ambition is to find a way of measuring... more
ABSTRACT The main contribution of this paper to the Cognitive Ergonomics field is to propose a new approach of the behavioral validity's assessment of driving simulators. In this paper, our ambition is to find a way of measuring "presence" to use it as a measure for ecological validity in driving simulators. The underlying assumption is that a person experiencing a strong sense of presence in the virtual environment will react in this environment as if it would be a real one. We propose to measure "presence" by measuring "attention" toward the driving task". Our objective is to demonstrate that the higher the subject's attention required by the primary driving task will be, the more the spatial presence will be felt. In the experiment we tried to vary "attention" by adding a dual task and by adding traffic and measure driving performance and subjective "presence" (MEC-SPQ; Measurement, Effects, Conditions-Spatial Presence Questionnaire). The main result is a lack of congruence between subjective and behavioral measures.
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Research Interests: Computer Science, Artificial Intelligence, Computer Vision, Eye tracking, Attention, and 15 moreMotion perception, Medicine, Optical Flow, Humans, Depth Perception, Optic Flow, Eye Movements, Optical Illusions, Adult, Eye Movement, Parallax, Motion Parallax, Binocular Disparity, Optokinetic Nystagmus, and Medical and Health Sciences
Research Interests: Computer Science, Perception, Cave, Virtual Reality, Geometry, and 4 moreOptic Flow, Scale, Tunnel, and Odometry
Virtual Reality (VR) leads to realistic experimental situations, while enabling researchers to have deterministic control on these situations, and to precisely measure participants' behavior. However, because more realistic and... more
Virtual Reality (VR) leads to realistic experimental situations, while enabling researchers to have deterministic control on these situations, and to precisely measure participants' behavior. However, because more realistic and complex situations can be implemented, important questions arise, concerning the validity and representativeness of the observed behavior, with reference to a real situation. One example is the investigation of a critical (virtually dangerous) situation, in which the participant knows that no actual threat is present in the simulated situation, and might thus exhibit a behavioral response that is far from reality. This poses serious problems, for instance in training situations, in terms of transfer of learning to a real situation. Facing this difficult question, it seems necessary to study the relationships between three factors: immersion (physical realism), presence (psychological realism) and behavior. We propose a conceptual framework, in which presence is a necessary condition for the emergence of a behavior that is representative of what is observed in real conditions. Presence itself depends not only on physical immersive characteristics of the Virtual Reality setup, but also on contextual and psychological factors.
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In everyday life, humans and most animals need to navigate in their environment, which produces multiple sources of perceptual information, such as locomotor cues (i.e. proprioceptive, efference copy and vestibular cues) and optic flow.... more
In everyday life, humans and most animals need to navigate in their environment, which produces multiple sources of perceptual information, such as locomotor cues (i.e. proprioceptive, efference copy and vestibular cues) and optic flow. However, few studies focused on the role of the visual consequences of walking (bob, sway, and lunge head motion) on self-motion perception. In a previous study, in which static observers were confronted to a visual simulation of forward motion, we have shown that adding rhythmical components to an optic flow pattern improved the accuracy of subjects' travelled distance estimations, in comparison with a purely translational flow. These results were attributable to the fact that oscillations may increase the global retinal motion and thus improve vection. Another hypothesis was that, walking step frequency being a significant cue in speed perception, visual consequences of step frequency might be at the origin of better estimations.To test this, we used the same experimental procedure in which observers, immersed inside a 4-sided CAVE, had to indicate when they thought they had reached a previously seen target. We tested whether different oscillation frequencies would affect the perception of distance travelled. Observers were confronted with 4 conditions of optic flows simulating forward self-motion. The first condition was generated by purely translational optic flow, at constant speed. The three other conditions of flows were vertical triangular oscillations with three kinds of frequencies added to linear forward motion, at the same forward speed. Results show that two groups can be distinguished. Regarding the first group, as in the previous study, adding rhythmic components improves the perception of distance travelled. For the second group, the higher the frequency, the earlier the answers, suggesting that these subjects related the oscillation frequency to their step frequency and perceived themselves as moving faster.
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Visual motion perception plays a fundamental role in vehicle guidance. For example, the control of one's trajectory is mainly performed on the basis of visual information about the characteristics of the trajectory and about the... more
Visual motion perception plays a fundamental role in vehicle guidance. For example, the control of one's trajectory is mainly performed on the basis of visual information about the characteristics of the trajectory and about the spatial layout. In particular, the pattern of optical flow resulting from the observer's self-motion through a stable environment is used by the subject to obtain information about his direction or speed of self-motion. However, little is known about the twofold task of a driver approaching an intersection, where he/she must control both his/her trajectory and detect the motion of other vehicles. In the present experiment, the perceptual ability of observers in relation to their level of driving expertise was evaluated. For the covering abstract, see IRRD 892069.
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... Title: PERCEPTION OF A MOVING VEHICLE WHEN APPROACHING AN INTERSECTION. ... 773D: AMSTERDAM; NEW YORK: NORTH-HOLLAND; NEW YORK, NY, USA: SOLE DISTRIBUTORS FOR THE USA AND CANADA, ELSEVIER SCIENCE PUB. CO., 1991. ...
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During self-motion, the driver's visual anticipation of the trajectory of another moving vehicle relies both on the global optical flow motion resulting from his/her self-motion and on local visual cues, such as the vehicle's... more
During self-motion, the driver's visual anticipation of the trajectory of another moving vehicle relies both on the global optical flow motion resulting from his/her self-motion and on local visual cues, such as the vehicle's optical trajectory and the relative optical motion between the vehicle and fixed elements in the environment. Here, we hypothesised that the complexity of the environment and the drivers' perceptual style influenced the use of such predictive visual information. Graphics displays simulated a driver's curvilinear movement towards an intersection where another vehicle was arriving. Subjects had to decide whether this vehicle would reach the intersection before or after them. Response times and differential thresholds were analysed. Overall, subjects' judgements were more accurate with realistic environments and with a road-sign near the intersection. Moreover, field-independent subjects were better than field-dependent subjects with realistic scenes, suggesting that they are better at picking up dynamic relevant information in a complex environment. For the covering abstract see IRRD E102207.
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AN EXPERIMENT IS REPORTED IN WHICH COMPUTERIZED CAR DRIVING SIMULATIONS WERE USED TO MANIPULATE ENVIRONMENT CHARACTERISTICS AND VEHICLES' TRAJECTORIES. VISUAL DISPLAYS SIMULATED THE CURVILINEAR APPROACH OF AN OBSERVER TO AN... more
AN EXPERIMENT IS REPORTED IN WHICH COMPUTERIZED CAR DRIVING SIMULATIONS WERE USED TO MANIPULATE ENVIRONMENT CHARACTERISTICS AND VEHICLES' TRAJECTORIES. VISUAL DISPLAYS SIMULATED THE CURVILINEAR APPROACH OF AN OBSERVER TO AN INTERSECTION. AN APPROACHING VEHICLE, COMING FROM THE RIGHT OF THE CURVED ROAD, WAS PROGRAMMED TO REACH THIS INTERSECTION EITHER 1 SECOND BEFORE OR AFTER THE OBSERVER. VISUAL DISPLAYS PROJECTED ON A TV MONITOR OR ON A LARGE SCREEN WERE STOPPED 2 SECONDS BEFORE THE OBSERVER REACHED THE INTERSECTION. SUBJECTS HAD TO DECIDE WHETHER THEY WOULD HAVE REACHED THE INTERSECTION BEFORE, AFTER OR AT THE SAME TIME AS THE APPROACHING VEHICLE. OVERALL, RESPONSES WERE CORRECT IN 62% OF CASES. A SPATIAL REFERENCE POINT (ROAD SIGN) NEAR THE INTERSECTION IMPROVED PERFORMANCE. HOWEVER, JUDGMENTS BECAME INCREASINGLY DIFFICULT FOR SMALL CURVATURE RADII WHERE RELATIVE VISUAL MOTION BECOMES AMBIGUOUS. MOREOVER, SUBJECTS APPEARED TO RELY MORE ON LOCAL VISUAL CUES WHEN VISUAL INFORMATION WAS PRESENTED ON A TV MONITOR, AND ON GLOBAL VISUAL CUES WHEN A LARGE-SCREEN DISPLAY WAS USED. (A) FOR THE COVERING ABSTRACT OF THE CONFERENCE SEE IRRD 858984.
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Research Interests: Information Systems, Engineering, Psychology, Cognitive Science, Computer Science, and 15 moreCyberpsychology, Psychotherapy, Depression, Video Games, Quality of life, Medicine, Virtual Reality, Humans, Female, Male, Follow-up studies, Computer User Interface Design, Questionnaires, Adult, and Phobic disorders
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Magnetic Confinement Fusion machines called tokamak (e.g. ITER and WEST projects), as well as many industrial projects, require a high integration level in a confined volume. The feasibility of installation and maintenance by an operator... more
Magnetic Confinement Fusion machines called tokamak (e.g. ITER and WEST projects), as well as many industrial projects, require a high integration level in a confined volume. The feasibility of installation and maintenance by an operator has to be considered in the early stages of the design. Virtual reality technologies have opened new perspectives and solutions to take into account assembly and maintenance constraints, using virtual mock-ups. In our applications, the human factor takes an important role. Since the operator interacts in a very tight and confined environment, he has to pay attention to his whole body relative to the virtual environment, in the absence of haptic feedback. In this context, enriched sensorial information, called "collision awareness feedback", must be defined, to favour an appropriate operator's spatial behavior with respect to the environment. In this paper, we present a preliminary study, testing the effect of vibrotactile feedback in a simple tracking task, compared to a pure visual feedback.
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The main contribution of this paper to the Cognitive Ergonomics field is to propose a new approach of the behavioral validity's assessment of driving simulators. In this paper, our ambition is to find a way of measuring “presence” to... more
The main contribution of this paper to the Cognitive Ergonomics field is to propose a new approach of the behavioral validity's assessment of driving simulators. In this paper, our ambition is to find a way of measuring “presence” to use it as a measure for ecological validity in driving simulators. In this way, the purpose of this study is especially to investigate the relationship between subjective ratings of presence and physiological responses in virtual driving environments. Six driving scenarios were, thus, created, resulting from crossing two independent variables, i.e., the visual realism of the virtual environment (three virtual environments were created ranging from very realistic to not realistic) and the degree of visibility on the road for each virtual environment (two conditions were proposed : very good visibility and very bad visibility). Whatever the scenario, the driving task was always to follow a red car without losing sight of its location. To measure subjective presence, attention and emotional involvement, Presence, and Mood questionnaires were used. As measures of physiological response, heart rate and skin conductance level were acquired and more specifically the heart rate variability (HRV) was calculated from the acquired ECG data. Driving performance (standard deviations of speed and lateral position) was also analyzed. Fourteen participants (25.4±4.5 years of age) were placed in a fixed base driving simulator and performed consecutively the six driving scenarios in a different order. The results show correlations between Presence Questionnaire scores and both HRV parameters (time and frequency domains) and skin conductance level. In the study, HRV parameters and skin conductance level appeared to indicate the participant's degree of presence.
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Nuclear maintenance operations require several types of cognitive and motor skills that can be trained in immersive environments. However, there is a lack of normalized methodological approaches to classify tasks and guide them for a... more
Nuclear maintenance operations require several types of cognitive and motor skills that can be trained in immersive environments. However, there is a lack of normalized methodological approaches to classify tasks and guide them for a potential transposition to immersive training. This paper proposes a methodological approach to classify nuclear maintenance tasks based on their complexity and the potential transfer of training obtainable from each type of immersion techniques and their related interactions.This proposed methodology provides a novel approach to compare various immersive technologies and interactions in a normalized way for a same industrial task.This paper aims at serving as a base for a methodological guide dedicated to the transposition of nuclear maintenance skills learned in immersive environments to real environment setups and proposes two future use cases based on this methodological approach.
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More than 1.3 million people lose their lives every year in traffic accidents. Improving road safety requires designing better vehicles and investigating drivers’ abilities more closely. Driving simulators are constantly being used for... more
More than 1.3 million people lose their lives every year in traffic accidents. Improving road safety requires designing better vehicles and investigating drivers’ abilities more closely. Driving simulators are constantly being used for this purpose, but the question which often arises as to their validity tends to be a barrier to developments in this field. Here we studied the validity of a simulator, defined as how closely users’ behavior under simulated conditions resembles their behavior on the road, based on the concept of drivers’ feeling of presence. For this purpose, the driving behavior, physiological state and declarative data of 41 drivers were tested in the Sherpa2 simulator and in a real vehicle on a track while driving at a constant speed. During each trial, drivers had to cope with an unexpected hazardous event (a one-meter diameter gym ball crossing the road right in front of the vehicle), which occurred twice. During the speed-maintenance task, the simulator showed a...
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L’approche bionique, consistant a donner des proprietes des etres vivants a un robot, est un moyen de diminuer efficacement l’ecart existant entre le fonctionnement d’un operateur humain et d’une machine. Dans cette etude, le comportement... more
L’approche bionique, consistant a donner des proprietes des etres vivants a un robot, est un moyen de diminuer efficacement l’ecart existant entre le fonctionnement d’un operateur humain et d’une machine. Dans cette etude, le comportement d’anticipation visuo-motrice observe chez l’homme lors du controle des deplacements a ete implemente sur une base mobile teleoperee. Cette implementation a ete effectuee suivant deux modes de couplage : orientation de camera asservie a la direction du deplacement (modele “ plate-forme ”) ou bien, direction du deplacement asservie a l’orientation de la camera (modele “ camera ”). Les resultats montrent 1 / qu’un teleoperateur est plus performant lorsqu’il pilote un vehicule pourvu d’anticipation et 2 / que cet avantage est d’autant plus marque suivant le modele “ camera ”. Cela confirme que la cooperation homme-machine beneficie de l’implantation sur l’engin teleopere de modes de couplages visuo-moteurs proches de ceux de l’operateur.