Sabine Langlois

ADAS HMI using peripheral vision

We propose to enhance utility of Advance Driver Assistance Systems (ADAS) with an interface that creates luminous signals able to be handled by peripheral vision while driving. The system, called Lighting Peripheral Display (LPD), consists of a box illuminated by LEDs whose light is reflected onto the windscreen. The shapes of the box are designed so that reflections can easily match the problems signaled by the ADAS. Surface, colors and movements are modulated to graduate urgency and to discriminate between the different assistance systems. A user test has been done on a driving simulator to compare a cluster with and without LPD. Both subjective and objective data (oculometry, vehicle parameters) were collected. They show that driving performance and comfort are enhanced by LPD. Reaction time is reduced for the most frequent warnings; perceived utility of ADAS is increased. However, drivers eyes tend to look at LPD instead of the cluster; peripheral vision utilization is thus not validated but, as ocular path is smaller with LPD, it helps the driver to keep his vision on the road.

Sonification of in-vehicle interface reduces gaze movements under dual-task condition

In-car infotainment systems (ICIS) often degrade driving performances since they divert the drivers gaze from the driving scene. Sonification of hierarchical menus (such as those found in most ICIS) is examined in this paper as one possible solution to reduce gaze movements towards the visual display. In a dual-task experiment in the laboratory, 46 participants were requested to prioritize a primary task (a continuous target detection task) and to simultaneously navigate in a realistic mock-up of an ICIS, either sonified or not. Results indicated that sonification significantly increased the time spent looking at the primary task, and significantly decreased the number and the duration of gaze saccades towards the ICIS. In other words, the sonified ICIS could be used nearly exclusively by ear. On the other hand, the reaction times in the primary task were increased in both silent and sonified conditions. This study suggests that sonification of secondary tasks while driving could improve the drivers visual attention of the driving scene.

Methodology for constructing a colour-difference acceptability scale

Observers were invited to report their degree of satisfaction on a 6‐point semantic scale with respect to the conformity of a test colour with a white reference colour, simultaneously presented on a PDP display. Eight test patches were chosen along each of the +a*, −a*, +b*, −b* axes of the CIELAB chromaticity plane, at Y = 80 ± 2 cd.m−2. Experimental conditions reliably represented the automotive environment (patch size, angular distance between patches) and observers could move their head and eyes freely. We have compared several methods of category scaling, the Torgerson‐DMT method (Torgerson, W. S. (1958). Theory and methods of scaling. Wiley, New York, USA); two versions of the regression method i.e. Bonnet’s (Bonnet, C. (1986). Manuel pratique de psychophysique. Armand Colin, Paris, France) and logistic regression; and the medians method. We describe in detail a case where all methods yield substantial but slightly different results. The solution proposed by the regression method which works with incomplete matrices and yields results directly on a colorimetric scale is probably the most useful in this industrial context. Finally we summarize the implementation of the logistic regression method over four hues and for one experimental condition.

Augmented reality versus classical HUD to take over from automated driving: An aid to smooth reactions and to anticipate maneuvers

The takeover phase from highly automated systems, when the transition phase is short (here 10s), is critical for the driver when he has been out of the driving loop. We conducted a simulator study on 26 drivers to compare three conditions: manual mode (MD), transition from automated driving (AD) to MD with a classical head up display (HUD), transition from (AD) to MD with an augmented reality (AR) HUD. In our scenarios, the driver has to take over to respect the navigation request for a lane change, and has to face slowing traffic in the destination lane. Compared to MD, driving behavior is altered in the transition phase up to 30s: the maximum speed on the brake pedal is higher, resulting acceleration being thus increased. AR reduces both these effects, thus improving driving comfort while facing slow traffic. AR also helps better anticipate the lane change maneuver: it increases the distance to the maneuver limit point. As such, the situational awareness seems to be improved by AR. Further analysis of eye tracking data and verbatim is needed to confirm this assumption based on driving data.

Virtual Head-up Displays for Augmented Reality in Cars: a User Testing to Validate the Congruence

Head-up displays (HUD) permit augmented reality (AR) information in cars. Simulation is a convenient way to design and evaluate the benefit of such innovation for the driver. For this purpose, we have developed a virtual HUD that we compare to real AR HUDs from depth perception features. User testing was conducted with 24 participants in a stereoscopic driving simulator. It showed the ability of the virtual HUD to reproduce the perception of the distance between real objects and their augmentation. Three AR overlay designs to highlight the car ahead were compared: the trapezoid shape was perceived as more congruent that the U shape overlay.

Speeded detection of sound signals based on temporal differences

Previous research has identified acoustic parameters modulating the perceived urgency of alarms. Such approaches have focused mainly on the subjective relationship between characteristics of the alarms and the perception of urgency. We suggest that an objective measurement will ensure with more certainty the effectiveness of the acoustic parameters and will help us to understand more precisely the underlying processes. We have to the improve the ability of warning signals to increase the probability of a faster reaction under emergency conditions. Thus, we performed two experiments using a speeded reaction‐time (RT) paradigm, under two tracking task conditions: motor and visual. Experiment 1 studied the influence of the tempo of the sequences. RT decreased as tempo became faster. Experiment 2 studied the influence of temporal irregularity. Outlier analyses show that RT decreased with the irregularity of the sequences. A scaled judgment of urgency was also given by subjects. Two underlying processes seem t...