Drivers’ Performance in Non-critical Take-Overs From an Automated Driving System—An On-Road Study

• Published in: Human factors Vol. 65; no. 8; pp. 1841 - 1857
• Main Authors: Rydström, Annie, Mullaart, Mattias Söderholm, Novakazi, Fjollë, Johansson, Mikael, Eriksson, Alexander
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-12-2023; Human Factors and Ergonomics Society
• Subjects: Accidents, Traffic; Automation; Automobile Driving; autonomous driving; Availability; driver behavior; Driving ability; experience; Exposure; human-automation interaction; Humans; Man-machine interfaces; Manual control; Reaction Time; Route selection; Traffic congestion; vehicle automation; human-automation interaction; vehicle automation; experience; driver behavior; autonomous driving
• ISSN: 0018-7208; 1547-8181; 1547-8181
• DOI: 10.1177/00187208211053460

Objective
The objective of this semi-controlled study was to investigate drivers’ performance when resuming control from an Automated Driving System (ADS), simulated through the Wizard of Oz method, in real traffic.
Background
Research on take-overs has primarily focused on urgent scenarios. This article aims to shift the focus to non-critical take-overs from a system operating in congested traffic situations.
Method
Twenty drivers drove a selected route in rush-hour traffic in the San Francisco Bay Area, CA, USA. During the drive, the ADS became available when predetermined availability conditions were fulfilled. When the system was active, the drivers were free to engage in non-driving related activities.
Results
The results show that drivers’ transition time goes down with exposure, making it reasonable to assume that some experience is required to regain control with comfort and ease. The novel analysis of after-effects of automated driving on manual driving performance implies that the after-effects were close to negligible. Observational data indicate that, with exposure, a majority of the participants started to engage in non-driving related activities to some extent, but it is unclear how the activities influenced the take-over performance.
Conclusion
The results indicate that drivers need repeated exposure to take-overs to be able to fully resume manual control with ease.
Application
Take-over signals (e.g., visuals, sounds, and haptics) should be carefully designed to avoid startle effects and the human-machine interface should provide clear guidance on the required take-over actions.