AssetID: 55858795
Headline: Out of sight in flight: U.S. team creates 'invisible' drone that disappears in the air
Caption: **VIDEO AVAILABLE: CONTACT INFO@COVERMG.COM TO RECEIVE** BY MARK WORGAN Engineers at Northwestern University have developed a drone that disappears while flying by exploiting the way the human eye perceives motion. Rather than relying on camouflage, transparent materials or light-bending technology, the researchers used the visual effect known as "motion blur" – the same phenomenon that can make the blades of a fast-spinning fan appear to disappear. The prototype, named Phantom Twist, spins up to 25 times a second, causing it to appear as a faint, ghost-like blur that blends into its surroundings. The team says the technology could eventually be used for monitoring wildlife, environmental surveys and infrastructure inspections while causing less visual disturbance. The research was presented on Thursday at the Robotics: Science and Systems 2026 conference in Sydney, Australia. Michael Rubenstein, who led the project at Northwestern University, said the team took a different approach to making drones less conspicuous. "Most efforts to hide drones focus on making them look like their surroundings. Instead, we asked whether we could design the drone itself around the way humans perceive motion,” he said. “This idea of low visibility through persistent motion is something few people have explored." Unlike a conventional quadcopter, which uses four separate rotors while the main body remains stationary, the Phantom Twist has a single motor and propeller. As the propeller rotates in one direction, the rest of the drone spins in the opposite direction. Mr Rubenstein said this eliminated the stationary parts that would normally remain visible. "For a typical quadrotor drone, the propellers are spinning, but the robot is stationary, he added. “So, you still see its body. For our drone, the whole thing is rotating, so there are no stationary parts." To create the design, the researchers generated around 20,000 potential drone configurations using a computational model capable of stable flight. Artificial intelligence and optimisation algorithms were then used to repeatedly reposition the drone's motor, propeller, batteries, circuit board and counterweight in search of the least visible arrangement. The most promising designs were tested against around 100 real-world backgrounds using a computer model designed to approximate human vision. Designs that blended more effectively into their surroundings received lower visibility scores before undergoing further refinement. The final design spreads its components across different heights and angles, preventing them from overlapping visually as the aircraft spins. The result is a faint, semi-transparent haze rather than a clearly defined object. According to the researchers' visibility measurements, the Phantom Twist is around 10 times less visually perceptible than a standard quadcopter. Emma Alexander, a computer vision specialist at Northwestern University, said the effect takes advantage of the way the human eye processes rapidly moving objects. "The human eye takes time to accumulate signals, roughly analogous to the exposure time of a camera,” she explained. “When an object spins quickly, we perceive it as blurring out and losing distinct features. Because this new drone is almost entirely transparent, its few opaque components are visually averaged with the background for an overall appearance of a slight haze." The researchers acknowledge the prototype still has limitations. The propeller produces an audible noise, while wires and support rods remain partly visible. Future versions are expected to use more transparent materials and quieter propulsion systems in an effort to make the aircraft even less noticeable. The study was supported by the US National Science Foundation.
Keywords: invisible,technology,tech,drone,feature,photo,video
PersonInImage: