When it comes to concerns about the widespread use of drones, one of the big ones is the worry that the things will crash on peoples' heads. That's why researchers at the University of Zurich have created a system to keep that from happening. Their technology allows a drone to regain stable flight after losing control, and to autonomously land in a "safe" area in the event of mechanical or battery failure.
The system was developed using small drones equipped with a single camera, and computer vision software running on an onboard smartphone processor.
While one of these drones is in stable flight, its software identifies distinctive landmarks in its environment. As long as those landmarks pass by in the manner that they should according to the flight commands, it knows that everything is proceeding properly.
If something such as a gust of wind or an obstacle suddenly knocks the aircraft off-kilter, however, it will automatically realign itself with those landmarks, instead of continuing to veer off in the wrong direction. "Our system works similarly to a tight-rope walker," said Matthias Faessler, who worked with Prof. Davide Scaramuzza on the project. "When you balance on a rope, you fixate on some static points in the environment and shift your weight accordingly to restore balance."
While GPS can also help in such situations, it's entirely possible that delivery drones flying amongst tall buildings could temporarily lose their GPS signal.
Additionally, the software continuously creates a 3D map of the drone's surroundings. Should a failure occur, it will identify flat, open "safe" terrain for the drone to land on, passing over "risky" areas. The drone will then proceed to set down there, under its own control.
It's reminiscent of a system recently developed at ETH Zurich, which allows multicopter drones to make controlled landings even if one of more of their propellers conk out.
Source: University of Zurich