Drones using sophisticated autonomy could provide the solution to unreliable GPS signals when flying in dense forest canopy, research suggests.
The findings focus on rescue missions in thick tree canopy and show how autonomous flight could help these type of search and rescue assignments.
In a paper being presented at the International Symposium on Experimental Robotics conference next week, researchers from Massachusetts Institute of Technology described an autonomous system for a fleet of drones to collaboratively search under dense forest canopies.
The drones use only on-board computation and wireless communication and require no GPS, something they hope will help when emergency services most need it.
The report details how each autonomous quadrotor drone is equipped with laser-range finders for position estimation, localisation, and path planning.
It creates an individual 3-D map of the terrain as it flies around and algorithms help it recognize unexplored and already-searched spots meaning it knows when it’s fully mapped an area.
An off-board ground station fuses individual maps from multiple drones into a global 3-D map that can be monitored by human rescuers.
Watch MIT’s video here:
One of the research paper authors, Yulun Tian, said: “Essentially, we’re replacing humans with a fleet of drones to make the search part of the search-and-rescue process more efficient.”
MIT went on to confirm the researchers had tested multiple drones in simulations of randomly generated forests, and tested two drones in a forested area within NASA’s Langley Research Centre.
In both experiments, each drone mapped a roughly 20-square-meter area in about two to five minutes and collaboratively fused their maps together in real-time.
The report also claims that the drones performed well across several metrics, including overall speed and time to complete the mission, detection of forest features, and accurate merging of maps.