Google's self-driving cars may have driven themselves 1.5 million miles since 2009, but it could take hundreds of years for robot-car makers to prove safety at the current testing rate, a new study said.
"Given that current traffic fatalities and injuries are rare events compared with vehicle miles traveled, we show that fully autonomous vehicles would have to be driven hundreds of millions of miles and sometimes hundreds of billions of miles to demonstrate their safety in terms of fatalities and injuries," said the Driving to Safety report from the Rand Corporation.
"Under even aggressive testing assumptions, existing fleets would take tens and sometimes hundreds of years to drive these miles – an impossible proposition if the aim is to demonstrate performance prior to releasing them for consumer use.
"Developers of this technology and third-party testers cannot simply drive their way to safety."
Even if companies develop "innovative methods of demonstrating safety and reliability," it still may not be possible to prove autonomous cars are safe, the report, said.
However, the report noted that self-driving cars have the potential to reduce the nation's 32,000 traffic fatalities, by taking human error out of the equation.
For the report's authors, the problem with determining robot-car safety lies in the comparatively low rate of road injuries and deaths versus miles driven. Although the 32,000 annual traffic deaths is a large number, it's small compared to the three trillion miles Americans drive every year.
So to find the rate at which self-driving cars crash and cause injuries or death, which would determine whether the vehicles are safe – and safer than humans – virtually astronomical numbers of testing miles would need to be driven, according to the report.
Accelerated testing, virtual testing and simulations, mathematical modelling, behaviour testing, pilot studies and "extensive focused testing of hardware and software systems" are possible supplements to test driving, to put self-driving cars on the road sooner than 100 years from now, the report said.
Time is of the essence in getting self-driving cars on the road, wrote innovation-management consultant Chunka Mui in Forbes.
"Every day by which we accelerate success can be measured in lives saved (more than 100), injuries prevented (more than 6,000), and dollars better spent (US$3.5bil/RM13.65bil)," Mui wrote.
"And, that is just in the United States. Worldwide, the numbers are even more staggering. In addition, millions could have speedier access to more affordable transportation. Congestion, pollution and dependency on oil could be reduced." — The Mercury News/Tribune News Service