Trial 3 – A Participant’s View

During the months of January and February, VENTURER is undertaking the third and final phase of a series of human factors experiments. Trial 3 is being held at the Bristol Robotics Laboratory, involving examining human reactions to the decisions made by an Autonomous Vehicle (AV) at junctions, crossings and overtaking parked cars on link roads. Unlike previous trials as well as interacting with conventional motor vehicles, it is also interacting with pedestrians and cyclists.

Participants in Trial 3 comprise of three different groups. One third are pedestrians who regularly make local journeys on foot and they have been asked to either walk to the trial or to come by public transport and complete their journey on foot. One third are regular cyclists who arrive at the trial on their bike. The final group are drivers with a range of driving experience. All of the participants are engaged in a series of repeated scenarios with the Wildcat autonomous vehicle in the ‘real world’ and the VENTURER Simulator and are asked to rate their ability to trust the decisions made by the vehicles.

The drivers experience the scenarios from within the Wildcat, whereas the pedestrians and cyclists observe the same events from the outside on the footways. In the simulator all participants are in the vehicle and rate their trust in the autonomous simulated vehicle as they encounter the same scenarios as in the Wildcat. Additionally, two-thirds of the participants are also asked to rate their trust in a driver when the car is driven manually.

The scenarios were designed to mirror the experiences of everyday situations on UK roads and included overtaking a parked vehicle with an oncoming cyclist, crossing a zebra crossing and turning right into a junction while detecting passing cyclists and crossing pedestrians, taking the appropriate action as required.

It is expected that the findings from Trial 3 will help to inform future research around Connected and Autonomous Vehicles’ (CAVs) abilities to integrate with other traffic on UK roads, including more vulnerable users such as people on foot and cyclists.

Two of the participants that have taken part in Trial 3 are Miriam, who has been making local journeys on foot for more than 20 years and Luke, a young driver with four and a half years’ experience.

Both Miriam and Luke expected CAV’s to be safer, with fewer accidents. Miriam added that “they will possibly encourage people not to have private cars, but to make it more of a shared thing, especially if people begin to think of transport in a different way.”

On the subject of safety, Luke noted that “when the driverless car approached crossing pedestrians and cyclists its speed and stopping distances were more appropriate than many drivers on the roads”. Miriam expressed that she felt very safe in the driverless car and the trial made her realise how unsafe she has felt at times when being driven by others.

As someone who has never owed or driven a car Miriam said that she would probably not like to own an AV, but “I would probably use them if they became part of public transport”. Luke, a professional musician, could see himself either owning or using a driverless car as it: “would definitely be better than having the responsibility of being behind the wheel myself. It would also be useful getting back from late night gigs and if you wanted a drink it would still drive you home.”

Although they were willing to embrace CAVs, both trial participants acknowledged that there are a number of barriers before this technology is widely accepted. Miriam pointed out that “some people are worried about giving control to what are essentially robots and generally people don’t accept that driving is dangerous”. Luke reflected that “the nature of our society at the moment is based around cars. The infrastructure such as drives in front of our houses assumes private car ownership, but at least initially private ownership of AVs will be too expensive”. So, a lot still needs to change before the full benefits that CAVs could bring are realised.