Ford Motor Company is partnering with Walmart and Postmates to study how consumers would handle self-driving cars making deliveries to their doors. Self-driving vehicles have been expected to bring all kinds of futuristic benefits, including smarter cities and safer streets and highways. But some U.K. researchers have identified a potentially more risqué repercussion of the autonomous vehicle revolution: more sex in cars since no one has to be behind the wheel. More than a dozen automakers and companies such as Uber, Lyft and Alphabet's self-driving car company Waymo have been testing autonomous vehicles. While some accidents have slowed those tests, overall safety is expected to be enhanced with autonomous net-connected vehicles, with researchers estimating up to 90 percent of traffic accidents could be avoided, U.K. researchers Scott Cohen, a tourism and transport professor at the University of Surrey, and Debbie Hopkins, a geography and environmental researcher University of Oxford, write in the Annals of Tourism Research.