Back seat drivers fear lead-footed autonomous cars, say boffins
Over to you, Google. How will robot cars improve traffic if passengers are panicked?
If you're the kind of person who reaches for a phantom brake-pedal when forced to be a passenger in a car, you're not alone. Research from psychologists in the US and UK suggests everybody's like that and that this tendency is going to be a problem for autonomous car-makers.
In short: whether they say so or not, most passengers want the driver to slow down, most of the time – and that has implications for the if-it-happens world of autonomous cars in which everybody will be a passenger.
As the researchers explain in their abstract: “car passengers start experiencing discomfort at lower rates of acceleration than car drivers; it is therefore plausible that occupants of an autonomously-operating vehicle may wish to instruct their vehicle to manoeuvre in a way that provides them greater ride comfort than if the vehicle-control algorithm simply mimicked human-driving-operation.”
In other words, if they have the choice, people travelling in autonomous vehicles are likely to tell their cars to travel slower than if the software were left to do the driving – or, for that matter, slower than they would go if they were behind the wheel themselves.
The study, a collaboration between Imperial College London and the State University of New York's New Paltz campus, notes that many of the benefits attributed to autonomous vehicles assume that the cars are left under software control.
For example, Google believes driverless cars will ease city congestion – something the Imperial College / SUNY research challenges, because if people start saying “Google, slow down” it'll be bad for congestion.
To model the impact on road congestion, the study took the passengers' preference to slow down, and tested that against a well-known congestion model – rail networks.
“The impacts were found to be larger when constraining the autonomous cars’ dynamics to the more-restrictive acceleration/deceleration profile of high-speed rail,” the study notes – although, so as to preserve the integrity of the model, they kept the cars within the highly-constrained acceleration/deceleration profiles of the rail system.
“Appropriate evidence regarding motorists’ preferences does not exist at present; establishing these preferences is an important item for the future research agenda”, the study notes. ®