Smartphones vs. in-vehicle data acquisition systems as tools for naturalistic driving studies: a comparative review

Naturalistic driving studies (NDS) are increasingly being used to investigate driver on-road behavior. In parallel, smartphones are gaining interest as data acquisition systems (DAS) in NDS instead of costly in-vehicle DAS. However, smartphone and in-vehicle DAS differ across several attributes and no current document outlines the implications of using smartphones as DAS in NDS. In this document, we present a comparative review of the advantages and disadvantages of using smartphone and in-vehicle DAS in NDS and discuss their implications. In addition, we present a brief account on prospective technological developments that might have further implications for using smartphones for studying and advancing road safety. Researchers and practitioners can use this review as a general guide to decide which DAS (smartphone or in-vehicle) to use in their NDS. For example, smartphones would be a cost-effective alternative for studying driving style (e.g., braking and speeding), but an inferior alternative to in-vehicle DAS for reconstructing crashes or near crashes and for studying short-term relationships between events (e.g., smartphone usage and hard braking). Researchers and practitioners can also use this review as an aid for the design of NDS with smartphones. For example, we show that it would be advisable to use beacons to know if participants were driving their vehicle or riding the bus, and that data completeness and accuracy would depend on battery charge and using a cradle. Prospective technologies might mitigate the shortcomings that we have outlined and might even dim the distinction between the different types of DAS

Cyclopean vs. Dominant Eye in Gaze-Interface-Tracking

User-centered design questions in gaze interfaces have been explored in multitude empirical investigations. Interestingly, the question of what eye should be the input device has never been studied. We compared tracking accuracy between the “cyclopean” (i.e., midpoint between eyes) dominant and non-dominant eye. In two experiments, participants performed tracking tasks. In Experiment 1, participants did not use a crosshair. Results showed that mean distance from target was smaller with cyclopean than with dominant or non-dominant eyes. In Experiment 2 participants controlled a crosshair with their cyclopean, dominant and non-dominant eye intermittently and had to align the crosshair with the target. Overall tracking accuracy was highest with cyclopean eye, yet similar between cyclopean and dominant eye in the second half of the experiment. From a theoretical viewpoint, our findings correspond with the cyclopean eye theory of egocentric direction and lend support to the hemispheric laterality approach of eye dominance. From a practical viewpoint, we show that what eye to use as input should be a design consideration in gaze interfaces

User Settings of Cue Thresholds for Binary Categorization Decisions

A brief narrative description of the journal article, document, or resource. The output of binary cuing systems, such as alerts or alarms, depends on the threshold setting-a parameter that is often user-adjustable. However, it is unknown if users are able to adequately adjust thresholds and what information may help them to do so. Two experiments tested threshold settings for a binary classification task based on binary cues. During the task, participants decided whether a product was intact or faulty. Experimental conditions differed in the information participants received: all participants were informed about a product's fault probability and the payoffs associated with decision outcomes; one third also received information regarding conditional probabilities for a fault when the system indicated or did not indicate the existence of one (predictive values); and another third received information about conditional probabilities for the system indicating a fault, in the instance of the existence or lack thereof, of an actual fault (diagnostic values). Threshold settings in all experimental groups were nonoptimal, with settings closest to the optimum with predictive-values information. Results corresponded with a model describing threshold settings as a function of the conditional probabilities for the different outcomes. From a practical perspective, results indicate that predictive-values information best supports decisions about threshold settings. Consequently, for users to adjust thresholds, they should receive information about predictive-values, provided that such values can be computed

Relationship Between Kinematic and Physiological Indices During Braking Events of Different Intensities

International audienc

Eye activity measures as indicators of drone operators’ workload and task completion strategies

International audienceWe studied whether eye activity patterns in a simulated drone operating task could be associated with workload levels and task completion strategies. Participants sent drones to suspected areas according to messages they received and according to self-initiated search. They were also required to validate whether suspected targets are indeed hostile prior to attacking them. We tested whether the number of suspected targets affected the number of eye transitions between task zones and whether it affected fixation durations on different task zones. We found that operators made less transitions between task zones as the number of targets increased. This was because they focused more on one zone and not the others. Interestingly, the zone they attended relatively more was the one they needed for attacking targets and not the ones where targets usually appeared. This was probably because attacking required extended cognitive operations. Findings demonstrated that eye activity patterns can be used to infer about task completion strategies and to identify workload levels, once these strategies are described. Workload levels and task completion strategies should therefore be studied by a combination of hypothesis driven and exploratory driven methods. Eye activity patterns can then be used as triggers for assisting overloaded operators

The relationship between level of engagement in a non-driving task and driver response time when taking control of an automated vehicle

International audienceDrivers of conditionally automated vehicles may occasionally be required to take control of their vehicle due to system boundaries, but their performance in such cases might be impaired if they were engaged in non-driving tasks. In this study, we conducted an experiment in a driving simulator, where the non-driving task involved playing a video game. We tested whether, after a take-over request (TOR), driver behaviour can be predicted from measures of game engagement. A sample of 28 participants drove in two counterbalanced conditions—manual driving and automated driving—and needed to change lanes at a certain time in their trip following auditory and visual requests. In the automated condition, drivers could play an endless runner game and were instructed to deactivate the automated mode to change lanes when they received a TOR. We used the proportion of glance durations on the game and the time between game sessions as indicators of game engagement. Findings showed that drivers were highly engaged in the video game during the automated driving session (more than 70% of the time) and that the inspection of driving-related areas of interests was significantly altered by this engagement. Moreover, the two indicators of game engagement predicted drivers’ response times to the TOR. Our findings suggest that indices of game engagement might assist in setting better timing for TORs and therefore, that it might be beneficial to synchronize measures of game engagement consoles with automated vehicle decision algorithms

Choosing protection: User investments in security measures for cyber risk management

Singapore National Research Foundation (NRF

Proceedings of the Human Factors and Ergonomics Society Europe Chapter 2019 Annual Conference

International audienc

Proceedings of the Human Factors and Ergonomics Society Europe Chapter 2019 Annual Conference

International audienc