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Faithful motion restitution in driving simulators normally focuses on track monitoring and maximizing the platform workspace by leaving aside the principal component—the driver. Therefore, in this work we investigated the role of the motion perception model on motion cueing algorithms from a user’s viewpoint. We focused on the driving behavior influence regarding motion perception in a driving simulator. Participants drove a driving simulator with two different configurations: (a) using the platform dynamic model and (b) using a supplementary motion perception model. Both strategies were compared and the participants’ data were classified according to the strategy they preferred. To this end, we developed a driving behavior questionnaire aiming at evaluating the self-reported driving behavior influence on participants’ motion cueing preferences. The results showed significant differences between the participants who chose different strategies and the scored driving behavior in the hostile and violations factors. In order to support these findings, we compared participants’ behaviors and actual motion driving simulator indicators such as speed, jerk, and lateral position. The analysis revealed that motion preferences arise from different reasons linked to the realism or smoothness in motion. Also, strong positive correlations were found between hostile and violation behaviors of the group who preferred the strategy with the supplementary motion perception model, and objective measures such as jerk and speed on different road segments. This indicates that motion perception in driving simulators may depend not only on the type of motion cueing strategy, but may also be influenced by users’ self-reported driving behaviors. This work was supported in part by Renault group and a PhD grant from ANRT (National Research and Technology Agency).

International audience; Simulator sickness is a well-known side effect of driving simulation which may reduce the passenger well-being and performance due to its various symptoms, from pallor to vomiting. Numerous reducing countermeasures have been previously tested; however, they often have undesirable side effects. The present study investigated the possible effect of seat vibrations on simulator sickness. Three configurations were tested: no vibrations, realistic ones and some that might affect the proprioception. Twenty-nine participants were exposed to the three configurations on a four-minute long automated driving in a simulator equipped with a vibration platform. Simulator sickness was estimated thanks to the Simulator Sickness Questionnaire (SSQ) and to a postural instability measure. Results showed that vibrations help to reduce the sickness. Our findings demonstrate that some specific vibration configurations may have a positive impact on the sickness, thus confirming the usefulness of devices reproducing the road vibrations in addition to creating more immersion for the driver.

International audience; 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.

This study proposes to investigate the effect of adding vibration feedback to a navigation task in virtual environment. Previous study used footstep vibrations and proprioceptive vibrations in order to decrease the cyber-sickness and increase the sense of presence. In this study, we experiment the same vibration modalities but with a new navigation method. The results show that proprioceptive vibrations do not impact the sense of presence neither the cyber-sickness while footstep vibrations increase sense of presence and decrease in a certain way cyber-sickness. Burgundy region through the JCE funding project

Arts et Metiers ParisTech built up the SAAM driving simulator with the partnership of Renault and Grand Chalon. This research was realized in the framework of the geDRIVER project.

The objective of this paper is to present the advantages of Model reference adaptive control (MRAC) motion cueing algorithm against the classical motion cueing algorithm in terms of biome- chanical reactions of the participants during the critical maneuvers like chicane in driving simu- lator real-time. This study proposes a method and an experimental validation to analyze the ves- tibular and neuromuscular dynamics responses of the drivers with respect to the type of the con- trol used at the hexapod driving simulator. For each situation, the EMG (electromyography) data were registered from arm muscles of the drivers (flexor carpi radialis, brachioradialis). In addi- tion, the roll velocity perception thresholds (RVT) and roll velocities (RV) were computed from the real-time vestibular level measurements from the drivers via a motion-tracking sensor. In or- der to process the data of the EMG and RVT, Pearson’s correlation and a two-way ANOVA with a significance level of 0.05 were assigned. Moreover, the relationships of arm muscle power and roll velocity with vehicle CG (center of gravity) lateral displacement were analyzed in order to assess the agility/alertness level of the drivers as well as the vehicle loss of control characteristics with a confidence interval of 95%. The results showed that the MRAC algorithm avoided the loss of adhe- sion, loss of control (LOA, LOC) more reasonably compared to the classical motion cueing algo- rithm. According to our findings, the LOA avoidance decreased the neuromuscular-visual cues lev- el conflict with MRAC algorithm. It also revealed that the neuromuscular-vehicle dynamics conflict has influence on visuo-vestibular conflict; however, the visuo-vestibular cue conflict does not in- fluence the neuromuscular-vehicle dynamics interactions.; International audience; The objective of this paper is to present the advantages of Model reference adaptive control (MRAC) motion cueing algorithm against the classical motion cueing algorithm in terms of biome- chanical reactions of the participants during the critical maneuvers like chicane in driving simu- lator real-time. This study proposes a method and an experimental validation to analyze the ves- tibular and neuromuscular dynamics responses of the drivers with respect to the type of the con- trol used at the hexapod driving simulator. For each situation, the EMG (electromyography) data were registered from arm muscles of the drivers (flexor carpi radialis, brachioradialis). In addi- tion, the roll velocity perception thresholds (RVT) and roll velocities (RV) were computed from the real-time vestibular level measurements from the drivers via a motion-tracking sensor. In or- der to process the data of the EMG and RVT, Pearson’s correlation and a two-way ANOVA with a significance level of 0.05 were assigned. Moreover, the relationships of arm muscle power and roll velocity with vehicle CG (center of gravity) lateral displacement were analyzed in order to assess the agility/alertness level of the drivers as well as the vehicle loss of control characteristics with a confidence interval of 95%. The results showed that the MRAC algorithm avoided the loss of adhe- sion, loss of control (LOA, LOC) more reasonably compared to the classical motion cueing algo- rithm. According to our findings, the LOA avoidance decreased the neuromuscular-visual cues lev- el conflict with MRAC algorithm. It also revealed that the neuromuscular-vehicle dynamics conflict has influence on visuo-vestibular conflict; however, the visuo-vestibular cue conflict does not in- fluence the neuromuscular-vehicle dynamics interactions.

Arts et Metiers ParisTech built the SAAM driving simulator in collaboration with Renault and Grand Chalon. This research study was realized in the framework of the geDriver project.; International audience; 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.

This paper explains the effect of a motion platform for driving simulators on postural instability and head vibration exposure. The sensed head level-vehicle (visual cues) level longitudinal and lateral accelerations (ax,sensed = ax_head and ay,sensed = ay_head, ayv = ay_veh and ayv = ay_veh) were saved by using a motion tracking sensor and a simulation software respectively. Then, associated vibration dose values (VDVs) were computed at head level during the driving sessions. Furthermore, the postural instabilities of the participants were measured as longitudinal and lateral subject body centre of pressure (XCP and YCP, respectively) displacements just after each driving session via a balance platform. The results revealed that the optic-head inertial level longitudinal accelerations indicated a negative non-significant correlation (r = −.203, p = .154 > .05) for the static case, whereas the optic-head inertial longitudinal accelerations depicted a so small negative non-significant correlation (r = −.066, p = .643 > .05) that can be negligible for the dynamic condition. The XCP for the dynamic case indicated a significant higher value than the static situation (t(47), p < .0001). The VDVx for the dynamic case yielded a significant higher value than the static situation (U(47), p < .0001). The optic-head inertial lateral accelerations resulted a negative significant correlation (r = −.376, p = .007 < .05) for the static platform, whereas the optic-head inertial lateral accelerations showed a positive significant correlation (r = .418, p = .002 < .05) at dynamic platform condition. The VDVy for the static case indicated a significant higher value rather than the dynamic situation (U(47), p < .0001). The YCP for the static case yielded significantly higher than the dynamic situation (t(47), p = .001 < 0.05).

Version éditeur de cet article : Aykent B, Merienne F, Paillot D, Kemeny A (2013) Influence of Inertial Stimulus on Visuo-Vestibular Cues Conflict for Lateral Dynamics at Driving Simulators. J Ergonomics 3: 113. doi:10.4172/2165-7556.1000113 This paper explains the effect of having an inertial stimulus (motion platform) for driving simulators on proximity to the reality for the sensed lateral dynamics with respect to the measurements and the perceptual fidelity using a questionnaire technique. To assess this objectively, the vestibular and vehicle level lateral accelerations (ay,sensed=ay_ vest, ayv =ay_veh ) were saved by using a motion tracking sensor and SCANeR studio software respectively. A confidence interval of 95% was chosen to test the correlations (Pearson’s correlation) and to fit models for the distributions of the visual-vestibular lateral accelerations with the multiple linear regression between the conditions of static (N=16) and dynamic (N=21) platform cases in terms of visuo-vestibular level lateral accelerations for the group of subjects (N=37). The results showed that the dynamic platform provides a higher lateral dynamics reality (positive correlation with an incidence of 90.48% for N=21) compared to the static configuration (negative correlation with an incidence of 50% for N=16) from Pearson’s correlation and a better fitted model and a lower visuo-vestibular cues’ conflict for the dynamic (R2 =0.429, the model is positive sloped, N=21) condition comparing to the static one (R2 =0.072, the model is negative sloped, N=16) from the multiple linear regression models. A two-tailed Mann Whitney U test yielded that the Ucomputed (2139)>Uexpected (1300.5) as p

Speed perception is an important task depending mainly on optic flow that the driver must perform continuously to control his/her vehicle. Unfortunately, it appears that in some driving simulators speed perception is under estimated, leading into speed production higher than in real conditions. Perceptual validity is then not good enough to study driver’s behavior. To solve this problem, a technique has recently seen the light, which consists of modifying the geometric field of view (GFOV) while keeping the real field of view (FOV) constant. We define our visual scale factor as the ratio between the GFOV and the FOV. The present study has been carried out on the SAAM dynamic driving simulator and aims at determining the precise effect of this visual scale factor on the speed perception. Twenty subjects have reproduced two speeds (50 and 90 km/h) without knowing the numerical values of these consigns, with five different visual scale factors: 0.70, 0.85, 1.00, 1.15, and 1.30. We show that speed perception significantly increases when the visual factor increases. A 0.15 modification of this factor is enough to obtain a significant effect. Furthermore, the relative variation of the speed perception is proportional to the visual scale factor. Besides, the modification of the geometric field of view remained unnoticed by all the subjects, which implies that this technique can be easily used to make drivers to reduce their speed in driving simulation conditions. However, this technique may also modify perception of distances.

This paper deals with the effects of different washout algorithms used for Stewart platforms on subjective and objective ratings. Washout algorithms are used to represent vehicle dynamics in a restricted spatial place. An adaptive washout algorithm was realized to control the hexapod platform, depending on the specific force error in longitudinal, lateral and vertical directions, in order to compare user’s experience with those in the case of classical algorithm. In this study, the simulator sickness has been evaluated for three algorithms in dynamic driving simulator situation in objective and subjective way.

This paper presents a speed perception study focusing on the impact of a visual scale factor. This factor corresponds to the ratio between the geometric field of view (of the camera) and the driver’s field of view covered by the screen. 20 participants have reproduced 2 speeds (50 and 90 km/h) without knowing the numerical values of these consigns, and with 5 different visual scale factors: 0.70, 0.85, 1.00, 1.15 and 1.30. We show that this visual factor has a significant impact on the speed reached by the subjects and that the variation of perceived speed can be deducted from the used visual scale factor. To be able to conduct this experiment, we had first to solve an image correction issue. As the visual display is projected on a cylindrical screen, a distortion correction must be performed. This correction is dependent on the viewer’s position and so is also dependent on the visual scale factor. We had then to improve our image warping approach to be able to take into account in real time the observer’s position (which was not the case until now). This paper presents a concise state of the art about image correction and some details about the implementation of the chosen algorithm.

In this paper, a method to link CAD models to an immersive virtual environment is proposed. CAD models cannot be viewed directly in a real-time visualization environment. CAD models have to be adapted to be viewed in an immersive environment with high quality rendering. The proposed method allows design review in application requesting high quality complex scene visualization in immersive virtual environment. Our application is dedicated to an immersive room called the MoVE (Mobile Virtual Environment). This display offers a particular place to the user. User is inside the virtual world. This position allows us to take care of the peripheral.

The virtual environment navigation may induces the simulator sickness depending on conditions and user’s profile. The potential virtual reality multimodality may provide solutions to these problems while improving the sense of presence. In this context, the objective of this research is to determine what is the impact of vibrational modalities for navigation in virtual environments on the simulation.A taxonomy of navigation methods is proposed. It results in 4 types, specific egocentric, specific exocentric, abstract egocentric and abstract exocentric. First we simulate rumble strip vibrations during a driving simulation. The experimentation exposed that these vibrations make driver more aware about the environment and his driving safer. We also develop 3 vibratory modalities, proprioceptive vibrations, footstep vibrations and continuous vibrations. Experimentations show that vibrations help to reduce simulator sickness and to increase the sense of presence depending on the used navigation method in the simulation. Last we develop and evaluate 2 vibration languages for guidance, Pushing pattern and Compas pattern. The evaluation exposes that Compass pattern is better in guiding the user., La navigation en environnement virtuel est susceptible d’induire le mal du simulateur selon les conditions et le profil des utilisateurs. Le caractère potentiellement multimodal de la réalité virtuelle est susceptible d’apporter des solutions à ces problèmes tout en améliorant le sentiment de présence. Dans ce contexte, l’objectif de ce travail de recherche est de déterminer quel est l’impact sur la simulation de l’apport des modalités vibratoires pour l’aide à la navigation dans un environnement virtuel.Pour cela une taxonomie des méthodes de navigation est proposée. Il en résulte 4 types, concrète égo-centrée, concrète exo-centrée, abstraite égo-centrée et abstraite exo-centrée. Dans un premier temps, des vibrations utilisées pour simuler des bandes rugueuses lors d’une simulation de conduite sont étudiées. L’expérimentation permet de conclure que ces vibrations rendent le conducteur plus attentif à l’environnement et donc sa conduite plus sûre. Par la suite nous avons développé les 3 modalités vibratoires suivantes, vibrations proprioceptives, vibrations synchronisées sur le pas et vibrations continues. L’évaluation de ces vibrations combinées avec différents types de méthode de navigation ont permis de montrer que les vibrations permettent de diminuer le mal du simulateur et d’augmenter le sentiment de présence. Ces travaux ont mis en évidence l’importance du choix de la modalité vibratoire à utiliser suivant l’effet souhaité en fonction de la méthode de navigation utilisée dans la simulation. Enfin, deux langages vibratoires ont été développés et évalués, le « Pushing Pattern » et le « Compass Pattern ». L’évaluation de ces langages a montré que le « Compass Pattern » était plus performant pour guider l’utilisateur dans un environnement virtuel.