Report: Driver responses to encountering automated vehicles in an urban environment

By 2nd February 2017Reports

The GATEway (Greenwich Automated Transport Environment) project aims to understand and identify ways to overcome the technical, legal and societal barriers of implementing automated vehicles in an urban environment. One potential issue for such implementation is a lack of a priori knowledge of the ways human drivers might respond to the presence of automated vehicles (AVs) in the driving environment, particularly if human drivers know that AVs are designed to be risk-averse and compliant with traffic rules.

To investigate this, 60 participants undertook 10 drives in the TRL driving simulator, comprising two distinct driving tasks: crossing a ‘give way’ junction and overtaking a slow-moving vehicle on an urban dual carriageway. At the junction, participants pulled into smaller gaps between vehicles when there were more AVs in the traffic, but there was no significant difference in gap size acceptance when participants intercepted AVs versus HDVs. When overtaking, participants typically chose to wait until the approaching vehicle had passed in all instances, regardless of whether the vehicle was an AV or HDV. Post-trial comments suggest that a few participants felt more confident about pulling out in front of the AV at the junction. However in most cases, participants’ decisions on when to undertake a manoeuvre were based on gap size assessments and judgements of safety.

As on-road exposure to AVs is currently extremely limited, drivers typically do not feel sufficiently knowledgeable about AV behaviour to treat them any differently than they would an HDV. Future research should seek to understand how drivers will behave when they have had greater exposure to AVs and how drivers might interact with AVs when under time pressure.

Download the report here: Driver responses to encountering automated vehicles in an urban environment