A Tricopter Drone with a Metal Detector Proves Adept at Mapping Possible Landmine Locations
This highly maneuverable drone, with a metal detector strapped to its nose, maps mines to make the world a safer place.
Researchers from the Autonomous Systems Lab of ETH Zürich are aiming to make landmine clear-up safer, by strapping a metal detector to an aerial drone to autonomously map minefields and mark potential mines for safe detonation.
"Micro aerial vehicles (MAVs) hold the potential for performing autonomous and contactless land surveys for the detection of landmines and explosive remnants of war (ERW)," the team explains of its work. "Metal detectors are the standard detection tool but must be operated close to and parallel to the terrain. A successful combination of MAVs with metal detectors has not been presented yet, as it requires advanced flight capabilities."
Those advanced flight capabilities are exactly what the team delivers in its project, brought to our attention by IEEE Spectrum, using a modified Voliro T tricopter drone with a modified Barret ACE300i metal detector payload plus sensor package including an Ouster OS0-128 LIDAR, a u-blox ZED-F9P RTK-GNSS receiver, a Bosch Sensortec BMI085 inertial measurement unit (IMU), and a custom microcontroller.
"Based on an online estimate of the terrain," the researchers explain, "our receding-horizon planner efficiently covers the area, aligning the detector to the surface while considering the kinematic and visibility constraints of the platform. We validate the robustness of the solution to individual sensor degeneracy by flying under the canopy of trees and over featureless fields. A simulated ablation study shows that the proposed planner reduces coverage duration and improves trajectory smoothness. Real-world flight experiments showcase autonomous mapping of buried metallic objects in undulated and obstructed terrain."
The team's real-world testing, which was carried out with metallic but non-explosive objects in place of actual landmines, demonstrated superior maneuverability from the Voliro drone's independently-moving thruster nacelles and a successful mapping of the metallic objects on a 3D representation of the terrain — even in areas covered by foliage. "Visualizing the metal detector response on the terrain map combined with the GNSS reference allows easy re-localization in hazardous areas for demining," the researchers note.
A preprint of the team's paper is available under open-access terms on Cornell University's arXiv server.