The influence of time-criticality on Situation Awareness when retrieving human control after automated driving

Abstract

Abstract² When applying automated driving as a means for congestion assistance, developers are challenged how to accommodate the transitions between automated and manually driving, especially because these transitions might occur regularly and suddenly. During automated driving, the ability to take over control is also aggravated due to the driver being placed out of the control-loop. To assess then the ability to retrieve human control, we tested within a driver simulator experiment the influence of criticality (available time) on Situation Awareness (SA) gained during time-critical take-overs within a scenario of congested driving. Though one of the applied measurement methods did not show the expected effect of SA on successfulness of taking back control, the results show that drivers are able to successfully retrieve control, also within time-critical situations. Furthermore, the results show that the ability to retrieve control is positively influenced if drivers gain increased levels of SA.

Situation Awareness and Transitions in Highly Automated Driving: A Framework and Mini Review

“…A number of studies which assessed driver behavior after transition from highly automated driving, found that the shorter time budget decreased the take-over quality, including percent of accidents and maximum longitudinal/lateral acceleration [32,33]. They also found that the higher complexity of the traffic increased the take-over time due to longer situation awareness regaining.…”

Driving automation interface design : supporting drivers' changing role

“…The same counts for raised levels of SA. That means if an interface helps to raise SA so does the chance for effective accident avoidance (Gold et al, 2013;Van den Beukel & Van der Voort, 2013). Results from an experiment of the author to test driver's ability to retrieve human control during time-critical take-over scenarios showed that the ability to retrieve control is positively influences if drivers gain increased levels of SA (Van den Beukel & Van der Voort, 2013).…”

“…In an earlier experiment that measured SA in simulated control-retrieving tasks, the authors found differences between SART and SAGAT approaches (Van den Beukel & Van der Voort, 2013) in that the longer period before situation retrieval with the SAGAT approach had a counter-productive influence on SA accuracy when compared to using the SART. Studies by other authors also raise questions regarding the reliability and validity of SAGAT and SART measurement methods (Endsley et al, 1998;Salmon et al, 2006).…”

“…Most studies show results that favour the SAGAT, for example by demonstrating better face validity (Salmon et al, 2006). Nevertheless, there is little information available from experiments on measuring SA in timecritical driving situations (Gold et al, 2013;Van den Beukel & Van der Voort, 2013). Consequently, we do not rely on a single measurement method and further recognise that both techniques are to an extent complementary.…”

“…Gold et al (2013) showed that providing a takeover request (i.e., a simple audio-visual warning) 5 -7s in advance ensures that drivers of a highly automated car avoided a stationary object, even if they were not attending to the road prior to the takeover request. Van den Beukel and Van der Voort (2013) found that drivers who were out-of-the-loop and travelling with time headways of about 1.5s (which are during manually driving considered 'safe'), failed in almost half of these occasions (47.5%) to avoid collision with a broken down vehicle during an unexpected event. However, this study also showed that providing an improved level of situation awareness (through e.g.…”