Vibrations in dynamic driving simulator: Study and implementation

This paper shows the effect of adding vibrations in a car cabin during driving simulation on driver perception. Actually, current dynamic driving simulators induce the simulator sickness and it still difficult for the driver to project himself in the virtual reality due to a lack of perception. To know the effect of vibrations on a subject, the effect of the whole body vibration must be defined, as the sources of vibration in a car cabin. After determining all the parameters we propose to determine a formula to produce the vibrations in function of the car state, the road and the boundary conditions. Then experimentation with nine subjects is done to define the exact effect of the vibrations and the new perception of the road in the simulation. In order to do these experimentations, three actuators were installed inside the cabin of the car driving simulator from Institut Image – Arts et Metiers ParisTech

The contribution of closed loop tracking control of motion platform on laterally induced postural instability of the drivers at SAAM dynamic simulator

This paper explains the effect of a motion platform closed loop control comparing to the static condition for driving simulators on postural instability. The postural instabilities of the participants (N=18, 15 male and 3 female subjects) were measured as lateral displacements of subject body centre of pressure (YCP ) just before and after each driving session via a balance platform. After having completed the experiments, the two-tailed Mann-Whitney U test was applied to analyze the objective data for merely the post-exposure cases. The objective data analysis revealed that the YCP for the dynamic case indicated a significant lower value than the static situation (U(18), p < 0,0001). It can be concluded that the closed loop tracking control of the hexapod platform of the driving simulator (dynamic platform condition) decreased significantly the lateral postural stability compared to the static operation condition. However the two-tailed Mann-Whitney U test showed that no significant difference was obtained between the two conditions in terms of psychophysical perception

Motion sickness evaluation and comparison for a static driving simulator and a dynamic driving simulator

This paper deals with driving simulation and in particular with the important issue of motion sickness. The paper proposes a methodology to evaluate the objective illness rating metrics deduced from the motion sickness dose value and questionnaires for both a static simulator and a dynamic simulator. Accelerations of the vestibular cues (head movements) of the subjects were recorded with and without motion platform activation. In order to compare user experiences in both cases, the head-dynamics-related illness ratings were computed from the obtained accelerations and the motion sickness dose values. For the subjective analysis, the principal component analysis method was used to determine the conflict between the subjective assessment in the static condition and that in the dynamic condition. The principal component analysis method used for the subjective evaluation showed a consistent difference between the answers given in the sickness questionnaire for the static platform case from those for the dynamic platform case. The two-tailed Mann–Whitney U test shows the significance in the differences between the self-reports to the individual questions. According to the two-tailed Mann–Whitney U test, experiencing nausea (p = 0.019 < 0.05) and dizziness (p = 0.018 < 0.05) decreased significantly from the static case to the dynamic case. Also, eye strain (p = 0.047 < 0.05) and tiredness (p = 0.047 < 0.05) were reduced significantly from the static case to the dynamic case. For the perception fidelity analysis, the Pearson correlation with a confidence interval of 95% was used to study the correlations of each question with the x illness rating component IRx, the y illness rating component IRy, the z illness rating component IRz and the compound illness rating IRtot. The results showed that the longitudinal head dynamics were the main element that induced discomfort for the static platform, whereas vertical head movements were the main factor to provoke discomfort for the dynamic platform case. Also, for the dynamic platform, lateral vestibular-level dynamics were the major element which caused a feeling of fear

Etude des lois de commande de la plateforme de simulation de conduite et influence sur le mal de simulateur

La simulation de conduite est fortement utilisée dans la recherche et le développement pour l'industrie automobile. Les simulateurs de conduite sont utilisés pour évaluer les prototypes véhicules pour la dynamique du véhicule et les systèmes d'aide à la conduite. Cependant, l'utilisation des simulateurs de conduite induit une problématique scientifique qui peut limiter son développement. En raison de son principe même, le simulateur de conduite ne restitue pas des mouvements du véhicule à l'échelle 1. Ce verrou cause des phénomènes de mal du simulateur qu'il est important d'étudier.Cette thèse propose d'étudier des méthodes et outils à mettre en œuvre dans les simulateurs de conduite statique ou dynamique. De cette mise en œuvre, des études sur le mal du simulateur sont menées grâce à des mesures objectives (via un capteur de suivi de mouvement, plate-forme de stabilité du corps, électromyographie) et subjectives (par l'intermédiaire de questionnaires). Des solutions algorithmiques et matérielles sont proposées et évaluées dans le contexte de la simulation de conduite.Les approches proposées dans cette thèse pour réduire le mal du simulateur sont:- Elaborer et évaluer les algorithmes de contrôle de la plate-forme mobile hexapode: sept algorithmes différents sont mis en œuvre.- Mesurer les effets liés au mal de simulateur sur les sujets aux niveaux vestibulaire, neuromusculaire et posturale.- Evaluer l'influence de l'implication des sujets sur le mal de simulateur (conducteurs et passagers).Simulation has been intensively involved nowadays in research and development for automotive industry. Driving simulators are one of those simulation techniques which are used to evaluate the prototypes for the vehicle dynamics and driving assistance systems. However with the driving simulator, there is a lock associated with its use. Because representing a permanent scenario as scale 1 is quite difficult. Because of that difficulty, motion/simulator sickness is an inevitably important topic to study.This thesis proposes to explore methods and tools to implement in static or dynamic simulators. In this implementation, studies of simulator sickness are conducted with objective measures (via a motion tracking sensor, platform for body stability, electromyography) and subjective (through questionnaires). These algorithmic or hardware solutions studies should be defined and applied at simulators. The proposed approaches to reduce or avoid simulator sickness in this thesis are:- Building control algorithms of motion hexapod platform: seven different algorithms are implemented.- Measuring the effects of inertia on subjects at vestibular, neuromuscular and postural levels.- Assessing the involvement of subjects (drivers and passengers).PARIS-Arts et Métiers (751132303) / SudocSudocFranceF

Effect of VR Device – HMD and Screen Display – on the sickness for Driving Simulation

In this article, an experimental procedure is presented in order to evaluate HMD oculus and medium range field of view ECO2 static simulator according to driving simulation sickness. The driving simulation sickness is investigated with respect to SSQ (simulator sickness questionnaire) and vestibular dynamics (head movements) of the driver participants for a specific driving scenario. The scenario of driving task is created by using open source “iiVR (institut image virtual reality)” software which is developed by Institut Image Arts et Métiers ParisTech. The experiments are executed in static mode for driving simulator

INFLUENCE OF DIFFERENT BLEACHING SYSTEMS ON THE BOND STRENGTH OF LAMINATE VENEER TO ENAMEL

Purpose: The objective of this in-vitro study was to examine the microtensile bond strength of a porcelain laminate veneer (PLV)&nbsp; to tooth surface bleached with photoactivation by blue light-emitting diode (LED) or diode laser. Methods: Eigthteen extracted human central incisors were randomly divided into three groups. Two sticks were obtained from each tooth (n=12). Before surface treatments; teeth were prepared to provide space for PLVs. The first group teeth were bleached with Whiteness HP which is contain 35% hydrogen peroxide (HP) and then photoactivated with a LED for 20 seconds. The second&nbsp; group were bleached with Laserwhite 20&nbsp; which is contain 46% HP and&nbsp; photoactivated with a diode laser for 30 seconds. The third group received no surface treatment and served as the control group. IPS Esthetic ceramic veneers were luted with Variolink II veneer cement . The teeth were sectioned to obtain porcelain-resin-enamel/dentin sticks and submitted to a MTB testing device. The maximum load at fractureÂ&nbsp; was recorded. Data were analyzed using one-way ANOVA followed by the Tukey HSD post-hoc test at a presetÂ&nbsp; α of&nbsp; 0.05. Results: One-way ANOVA revealed that there was significant difference between LED unit group and control group (p&lt;.05) but no statistical differences were observed with diode laser group (p&gt;.05)&nbsp; The LED unit group presented significantly lower bond strength value (6.49±2.3 MPa) than diode laser (8.49 ±3.1 MPa) and control groups (9.53±2.7 MPa). Conclusion: The results suggested that bleaching therapy with activation by LED or diode laser reduced the bond strength of IPS Esthetic ceramic veneers to tooth surfaces. Keywords: Teeth Bleaching; Photoactivation; Semiconductor lasers; Diode laser; Microtensile

INFLUENCE OF DIFFERENT BLEACHING SYSTEMS ON THE BOND STRENGTH OF LAMINATE VENEER TO ENAMEL

Purpose: The objective of this in-vitro study was to examine the microtensile bond strength of a porcelain laminate veneer (PLV)&nbsp; to tooth surface bleached with photoactivation by blue light-emitting diode (LED) or diode laser. Methods: Eigthteen extracted human central incisors were randomly divided into three groups. Two sticks were obtained from each tooth (n=12). Before surface treatments; teeth were prepared to provide space for PLVs. The first group teeth were bleached with Whiteness HP which is contain 35% hydrogen peroxide (HP) and then photoactivated with a LED for 20 seconds. The second&nbsp; group were bleached with Laserwhite 20&nbsp; which is contain 46% HP and&nbsp; photoactivated with a diode laser for 30 seconds. The third group received no surface treatment and served as the control group. IPS Esthetic ceramic veneers were luted with Variolink II veneer cement . The teeth were sectioned to obtain porcelain-resin-enamel/dentin sticks and submitted to a MTB testing device. The maximum load at fractureÂ&nbsp; was recorded. Data were analyzed using one-way ANOVA followed by the Tukey HSD post-hoc test at a presetÂ&nbsp; α of&nbsp; 0.05. Results: One-way ANOVA revealed that there was significant difference between LED unit group and control group (p&lt;.05) but no statistical differences were observed with diode laser group (p&gt;.05)&nbsp; The LED unit group presented significantly lower bond strength value (6.49±2.3 MPa) than diode laser (8.49 ±3.1 MPa) and control groups (9.53±2.7 MPa). Conclusion: The results suggested that bleaching therapy with activation by LED or diode laser reduced the bond strength of IPS Esthetic ceramic veneers to tooth surfaces. Keywords: Teeth Bleaching; Photoactivation; Semiconductor lasers; Diode laser; Microtensile

Effect of Closed-Loop Motion Cueing Algorithm for a Six-Degrees-of-Freedom Dynamic Simulator on Pupil Diameter as a Driver Stress Factor

This paper describes the contribution of the closed-loop control of the motion platform (six degrees of freedom: longitudinal, lateral, and vertical displacements; pitch, roll, yaw) and motion platform’s three-dimensional (3D) displacement scale factor (SF) (0.2 and 1.0) on eye pupil diameter (PD) as an objective measure of driver cognitive load. Longitudinal, lateral, and vertical accelerations as well as longitudinal, lateral, and vertical positions from the center of gravity (CG) of the vehicle were registered through the driving simulation software SCANeRstudio® from OKTAL. Closed-loop control decreases the driver mental load. This type of closed-loop control can be used to decrease the driver mental load

Simulation sickness comparison between a limited field of view virtual reality head mounted display (Oculus) and a medium range field of view static ecological driving simulator (Eco2)

In this article, an experimental procedure is presented in order to evaluate the role of having HMD oculus and (Eco2 driving simulator) in terms of driving simulation sickness. The driving simulation sickness is investigated with respect to SSQ (simulator sickness questionnaire) and vestibular dynamics (head movements) of the driver participants for a specific driving scenario. The scenario of driving task is created by using open source “iiVR (institut image virtual reality)” software which is developed by Institut Image Arts et Métiers ParisTech. The experiments are executed in static mode for the driving simulators