Self-driving cars are getting better every day, and it's likely that they'll be a common sight on real-world asphalt within a decade or so. But what happens when they need to go off that asphalt?

That's what engineers at Ford are investigating, and they've come up with a possible solution. They've built a drone system that can guide self-driving cars when they need to go off-road, mapping the terrain beyond what the vehicle's sensors can detect.

"At some point, people are going to want to take their autonomous vehicle into the woods or off road where the drone could guide them," Alan Hall, spokesman for Ford's in house technology department, told AFP.

Hall says that the idea came out of a brainstorming session among researchers and engineers working on the company's autonomous car. The drone would normally be housed within the vehicle, but could be flown as necessary when digital maps prove insufficient.

Teaching and Learning

To that end, Ford earlier this year held a contest to teach a drone that could do just that. Working with Chinese drone manufacturer DJI, programmers had to get a drone to fly from and return to a moving vehicle. Only one out of ten competitors succeeded.

"It was a really cool challenge," said Hall.

The next step will be to work with a team of researchers at the company's research centre in Palo Alto to further the technology and help autonomous vehicles solve future navigation challenges.

"Ultimately, customers benefit as we open ourselves to new ideas and advance mobility using emerging technologies," added Ford's Tony Lockwood, manager of the virtual driver system.