'Give passengers sensor information to build trust in driverless cars'

The latest driverless advances such as vehicle-to-vehicle communication should be explained to the general public to boost confidence in the technology, researchers have recommended.

Manufacturers should also consider sharing information from autonomous vehicle sensors with passengers to allay fears of dangerous driving, said the team from the University of Warwick’s WMG.

The “valuable lessons” came from an autonomous vehicle trial in which 43 public volunteers were driven around a large warehouse designed to resemble a pedestrianised town centre. Half were given four journeys in an autonomous vehicle driving with “full machine efficiency, using all its capabilities to drive in as safe and efficient manner as possible”. The others were given four journeys in autonomous vehicles that tried to closely emulate average human driving patterns. They then scored the level of trust in the autonomous vehicles.

The trial found only a marginal preference for the efficient machine method, and the gap narrowed over the four journeys. Confidence grew in both styles as passengers became accustomed to the experience. One differentiation between the methods was passenger preference for the machine method’s smoother braking and acceleration, while passengers in both styles complained about sharp turning, with the machine style criticised more.

The most diverse and surprising reactions came to the vehicles’ behaviour at junctions, the researchers said. Vehicles driving like machines would go straight into junctions without stopping if there was no threat, while human-style ‘drivers’ always stopped and ‘peeked’ out gradually. Neither approach was perfect, and both were disliked.

Although the feedback was complex and contradictory, the WMG researchers said there were three key lessons: “there is clearly a need to give the general public the details of the driving systems, for example, the recent technological features such as vehicle-to-vehicle communication”; “for passengers in a vehicle, consideration should be given to having a display and/or audio information that shares some of the information the vehicle is using so users can understand that the system is aware of hazards beyond the field of view”; and “there may be some merit in presenting the full benefits of the most efficient methods of machine-based driving progressively when mass use is first introduced, so that passengers can build confidence over time.”

The research was published in Information.