Zeljko Medenica

Augmented reality vs. street views: a driving simulator study comparing two emerging navigation aids

Prior research has shown that when drivers look away from the road to view a personal navigation device (PND), driving performance is affected. To keep visual attention on the road, an augmented reality (AR) PND using a heads-up display could overlay a navigation route. In this paper, we compare the AR PND, a technology that does not currently exist but can be simulated, with two PND technologies that are popular today: an egocentric street view PND and the standard map-based PND. Using a high-fidelity driving simulator, we examine the effect of all three PNDs on driving performance in a city traffic environment where constant, alert attention is required. Based on both objective and subjective measures, experimental results show that the AR PND exhibits the least negative impact on driving. We discuss the implications of these findings on PND design as well as methods for potential improvement.

Contextual push-to-talk: shortening voice dialogs to improve driving performance

We present a driving simulator-based evaluation of a new technique for simplifying in-vehicle device interactions and thereby improving driver safety. We show that the use of multiple, contextually linked push-to-talk buttons (Multi-PTT) shortens voice dialog duration versus the use of a conventional, single push-to-talk button (Single-PTT). This benefit comes without detriment to driving performance or visual attention to the forward roadway. Test subjects also preferred the Multi-PTT approach over the conventional approach, and reported that it imposed a lower cognitive workload.

Video call, or not, that is the question

New technologies have made video calling in vehicles possible. Results from a driving simulator experiment indicate that video calling reduces visual attention on the road. While in some situations drivers would refrain from engaging in this activity, our results should serve as a warning to interface designers, lawmakers, transportation officials, and drivers that video calling presents a real distraction from driving.

Estimating cognitive load using pupil diameter during a spoken dialogue task

We explore the feasibility of using pupil diameter to estimate how the cognitive load of the driver changes during a spoken dialogue task with a remote conversant. The conversants play a series of Taboo games, which do not follow a structured turn-taking nor initiative protocol. We contrast the drivers pupil diameter when the remote conversant begins speaking with the diameter right before the driver responds. Although we find a significant difference in pupil diameter for the first pair in each game, subsequent pairs show little difference. We speculate that this is due to the less structured nature of the task, where there are no set time boundaries on when the conversants work on the task. This suggests that spoken dialogue systems for in-car use might better manage the drivers cognitive load by using a more structured interaction, such as system-initiative dialogues.