The team based these new drones on a previous "flying monkey" robot one of them developed. That one can fly, grasp surfaces and crawl/hop around. These new machines, however, are autonomous, loaded with "path-planning" algorithms to ensure the eight drones in the fleet don't bump into each other and into other objects. Further, the team attached two small motors with wheels to the bottom of each drone. During their tests, they found that adding those driving components decreased their drones' max flying distance by 14 percent due to the extra weight. That said, the machines are still capable of flying up to 300 feet, and the loss is offset by the gain in efficiency from driving, which uses less power.

The team's drones work so well, in fact, that the researchers believe they present another approach to designing flying cars. CSAIL Director Daniela Rus said in a statement:

"As we begin to develop planning and control algorithms for flying cars, we are encouraged by the possibility of creating robots with these capabilities at small scale. While there are obviously still big challenges to scaling up to vehicles that could actually transport humans, we are inspired by the potential of a future in which flying cars could offer us fast, traffic-free transportation."

You can watch the drones and their path-planning algorithms at work in the video below as they navigate a small makeshift neighborhood with cardboard boxes for buildings: