People ride on a driverless electric vehicle at the Nanyang Technological University (NTU) in Singapore, September 2013. (Photo by Edgar Su/Reuters)





An onboard display monitor shows other vehicles as a staff member of Toyota drives its self-driving technology Mobility Teammate Concept prototype car hands-free on the Metropolitan Expressway in Tokyo, October 2015. (Photo by Yuya Shino/Reuters)





A prototype of Goodle's self-driving vehicle during a media preview in Mountain View, September 2015. (Photo by Elijah Nouvelage/Reuters)





A crew member inputs his route in an autonomous vehicle during a demonstration in Singapore, October 2015. (Photo by Edgar Su/Reuters)





Members of the media disembark from an autonomous vehicle during a demonstration in Singapore, October 2015. (Photo by Edgar Su/Reuters)





A driverless vehicle at Vanke's Building Research Centre testing area in Dongguan, south China's Guangdong province, November 2015. (Photo by Tyrone Siu/Reuters)





A screen displays views from various onboard sensors in a Google self-driving vehicle before a presentation in Mountain View, California, May 2014. (Photo by Stephen Lam/Reuters)





The first autonomous and electric shuttle of PostAuto Schweiz in the old village of Sion, Switzerland, June 2016. (Photo by Ruben Sprich/Reuters)





The Mercedes-Benz F015 Luxury in Motion autonomous concept car, January 2015. (Photo by Steve Marcus/Reuters)





The interior of the Mercedes-Benz F015 Luxury in Motion autonomous concept car, January 2015. (Photo by Steve Marcus/Reuters)





The self-driving delivery vehicle from Silicon Valley startup Nuro, intended to be used for local commerce, is shown in San Francisco on January 30, 2018. (Photo by Reuters/Courtesy of Nuro)





Toyota displays the e-Palette, a fully self-driving electric concept vehicle designed to be used for ride hailing, parcel delivery services and other uses, January 2018. (Photo by Rick Wilking/Reuters)





The interior of an autonomous Volkswagen I.D. Buzz concept vehicle, November 2017. (Photo by Mike Blake/Reuters)





An autonomous Volkswagen I.D. Buzz concept vehicle, November 2017. (Photo by Mike Blake/Reuters)





Ford shows a test vehicle designed to study consumer reaction to driverless cars with a hidden human driver, at the Ford offices in Washington, D.C. September 2017. (Photo by David Shepardson/Reuters)





The French-made EZ10 autonomous bus runs at a university campus in Taipei, July 2017. (Photo by Tyrone Siu/Reuters)





Japan's DeNA Co's Robot Shuttle during its demonstration in Tokyo, July 2016. (Photo by Toru Hanai/Reuters)





The Smart concept autonomous car Vision EQ fortwo model, September 2017. (Photo by Kai Pfaffenbach/Reuters)