Designing safer vehicles with eye tracking

Prof. Jun Ma leads the Human-Vehicle Relationship Laboratory (HVR Lab) at the School of Automotive at Tongji University. The HVR Lab focuses on automotive product design and innovation, including human-computer interaction, human-vehicle relationships, and the design and development of intelligent automotive cockpits. In their latest study, researchers from the HVR Lab investigated the impact of passenger displays on drivers' visual and cognitive loads, as well as driving performance, using Tobii Pro Glasses 3.

Digital technology applications have rapidly advanced within the automotive industry, offering a range of functions and features for navigation, entertainment, and in-vehicle control for drivers and passengers. These advancements primarily stem from the integration of larger and more numerous displays within car interiors. The passenger's display allows passengers to enjoy visual and audio entertainment during the ride. While these features are popular among consumers, there is a notable research gap regarding how passenger displays might distract drivers, posing new safety concerns. Specifically, little is known about how the passenger display might affect the driver’s workload and driving performance.

Does a passenger display cause a driver’s distraction?

Eye tracking technology is an objective and non-invasive way to gather data about drivers’ visual behavior under various driving conditions in the vehicle and the surrounding environment. In this study, the researchers investigated the effects of video played on the passenger’s display on the driver’s workload and driving performance. Using Tobii Pro Glasses 3 wearable eye tracker and Tobii Pro Lab software, the researchers collected visual attention data on a real-vehicle simulator with a high ecological validity. To assess whether the passenger’s display influences driving behavior and workload, the researchers investigated the following factors:

• Visual workload was assessed by measuring glance behavior (e.g., total glance duration, number of glances) on the passenger’s display using Tobii Pro Glasses 3. For the analysis, researchers utilized Tobii Pro Lab software.

• Cognitive workload was measured in an auditory detection response task. The task required the driver to press a microswitch attached to the steering wheel whenever they heard a beep.

• Driving performance consisted of measurements of deviations in speed and lane position.

Eye tracking effectively measures visual workload while driving

In a simulated driving environment on a three-lane highway, participants engaged with the passenger’s display while media material was played on the passenger screen and responded to the detection response task.

The results revealed increased cognitive and visual workload and worse driving behavior when participants drove with the passenger’s display active. This was reflected by increased drivers’ average fixation duration when the video played on the passenger screen compared to only audio conditions. The drivers showed a higher average glance duration when attending to the passenger’s screen, compared to control conditions, indicating an increased visual workload. As the passengers watched video content on the passenger’s display, drivers displayed erratic driving behavior, such as fluctuating speeds and lane deviations. Moreover, the drivers also had increased reaction times in an auditory detection response task, suggesting a higher cognitive load while driving with the passenger’s display active.

This research study shows how drivers’ interaction with the passenger’s display shapes their behavior and safety. It invites refinements in the ongoing development and application of passenger displays, emphasizing the need to balance entertainment and driving focus.

Cited publication

Ma, J., Li, J., Wang, W., Huang, H., Zhang, X., & Zhao, J. (2024). The impact of co-pilot displays use on driver workload and driving performance exploring the impact of co-pilot display on drivers’ workload and driving performance. Applied Ergonomics, 114, 104138.