How Do Drivers Self-Regulate their Secondary Task Engagements? The Effect of Driving Automation on Touchscreen Interactions and Glance Behavior

TL;DR

This study investigates how different levels of driving automation influence drivers' engagement with touchscreen tasks and glance behavior, revealing increased distraction during automation and highlighting factors affecting driver self-regulation.

Contribution

It provides the first detailed analysis of how driving automation impacts drivers' secondary task engagement and glance behavior using real-world data.

Findings

Drivers engage more with touchscreens during automation.

Glance durations toward touchscreens increase by 12-20% during automation.

Automation effects on driver behavior surpass those of speed and road curvature.

Abstract

With ever-improving driver assistance systems and large touchscreens becoming the main in-vehicle interface, drivers are more tempted than ever to engage in distracting non-driving-related tasks. However, little research exists on how driving automation affects drivers' self-regulation when interacting with center stack touchscreens. To investigate this, we employ multilevel models on a real-world driving dataset consisting of 10,139 sequences. Our results show significant differences in drivers' interaction and glance behavior in response to varying levels of driving automation, vehicle speed, and road curvature. During partially automated driving, drivers are not only more likely to engage in secondary touchscreen tasks, but their mean glance duration toward the touchscreen also increases by 12% (Level 1) and 20% (Level 2) compared to manual driving. We further show that the effect of driving automation on drivers' self-regulation is larger than that of vehicle speed and road curvature. The derived knowledge can facilitate the safety evaluation of infotainment systems and the development of context-aware driver monitoring systems.