Army-Developed Sensor System Helps Drones Avoid Power Lines
Power lines are a consistent obstacle for small autonomous drones. Now, U.S. Army researchers say they have a solution.
Drones are increasingly used for power line upkeep and freight delivery. But one persistent issue that has plagued this technology is hard-to-see power lines, which are located at roughly the same height that drones fly.
To address this issue, researchers at the U.S. Army's Research Laboratory (ARL) (for Combat Capabilities Development Command) have developed a sensor and an accompanying software application that will allow drones and unmanned aerial systems (UAS) to adjust their flight paths and navigate around electrical power lines, so long as the power line is carrying a current.
According to the researchers, the technology employs a novel sensor system made of field and 3D sensors with low-power processing methods. These devices, along with specialized software, enables unmanned drones and systems to identify power lines and avoid collisions with them.
A Better Detection Algorithm
Although the team’s approach is unique, the detection of power lines isn’t a new breakthrough. Power line detection and avoidance technologies already exist. These technologies use radar and/or optical sensors and have been deployed in many successful applications.
Using 3D sensors and an in-house algorithm, unmanned aerial systems can better avoid collision with wires. Image used courtesy of the U.S. Army CCDC Army Research Laboratory
“Power lines are small and difficult to see with radar or optical sensors, but they generate large fields that can be easily detected with low-power, low-cost, passive electric- and magnetic-field sensors,” said researcher David Hull, who is responsible for developing the new approach.
However, existing systems are bulky, expensive, and power-intensive. They also have significant technical limitations depending on where, when, and how they’re deployed. In contrast, ARL's system is cost-effective and easy to deploy, using only field electromagnetic sensors for detection measurement and an in-house algorithm to map power line locations.
With the combination of both sensing modalities in a single sensor, the ARL research team was able to estimate the direction of power flow. This is something that existing sensor technologies cannot do.
It’s also capable of mapping out power grids or locating damaged wires, meaning that it has dual-use potential in addition to offering the military a better way to avoid electric power lines while on the move.
Manifold Robotics’ powerline-safe drone platform based on technology licensed from the Army Research Laboratory. Image used courtesy of Manifold Robotics
ARL recently announced plans to work with a start-up company in New York, Manifold Robotics, to produce the new technology for commercial drone applications. A patent has been secured for the endeavor.
Engineers at Manifold say they intend to create a drone-based system that can detect power lines at a distance and calculate their precise location to facilitate planning and safe navigation in real-time to improve efficacy. In addition, the technology is expected to aid the development of drone applications like power line inspection systems and freight delivery drone solutions.