Where consumers see a plus for driverless cars

Driverless cars have many problems to solve before becoming widely available. But apparently they're getting started on the road to consumer acceptance.

A study released this week by the University of Michigan Transportation Research Institute showed that 70 percent of 1,500 respondents in the U.S., Australia and the U.K. believe self-driving cars would lead to fewer crashes on the road and better gas mileage, while 57 percent had positive views about driverless cars.

However, more than three-quarters of respondents said they're still concerned about equipment or system failures in autonomous cars.

Nissan ( NSANY) and General Motors (GM) have said they may have marketable self-driving cars by 2020. But many of the toughest issues involve regulation and highway safety. In fact, the National Highway Traffic Safety Administration has said previously in a statement: "The car -- no matter how automated -- is not yet ready to be more than a co-pilot. And every co-pilot needs a pilot. Before self-driving vehicles can roam our streets, we have to resolve some of the challenges."

Some of the technology involved in self-driving cars is already being used in existing models. The 2014 Mercedes-Benz S class can brake and steer itself for a few seconds under certain conditions. Mercedes, BMW, Lexus and some other brands have models with automated cruise control that keeps your car a safe distance behind the one ahead and if the radar system senses an imminent crash, puts on the brakes.

"People are aware that they already drive cars controlled partly by computers," says Des Toups of Insurance.com, which also did a survey on the subject. "Now they see features like collision avoidance on new models and hear about Google cars hitting the road in a couple of years. An autonomous car is not science fiction any more."

Google's ( GOOG) research project has been one of the most thorough and advanced. The company has convinced California, Nevada, Michigan and Florida to pass laws allowing self-driving cars on their roads for testing with certain safeguards. Analysts believe, however, that Google would ultimately try to sell a successful driverless car to the auto industry rather than market the vehicle itself.

As quickly as research may be moving, questions such as how autonomous cars will mix with conventional cars and how liability is assessed in case of an accident remain to be solved.

"I suspect we will first see self-driving cars on expressways only, cruising in their own specific lane," analyst Bill Hampton of Autobeat Group told Insurance.com. "A world where self-driving cars can go everywhere and handle door-to-door trips is more like 20 years away."