Researchers at EPFL have developed a unique unmanned aerial vehicle inspired by geckos, designed to perch on vertical poles after crashing into them. Named PercHug, this drone could revolutionize tasks like inspection and surveillance.
The team from EPFL’s Laboratory of Intelligent Systems focused on mimicking nature’s perching methods, aiming for a passive landing approach. Inspired by geckos’ ability to crash-land on tree trunks and then latch on, they designed a UAV with an upturned nose and rigid tail made from lightweight materials, weighing just 550 g and boasting a wingspan of 96 cm.
Upon impact with a pole, the drone’s upturned nose helps it transition from horizontal flight to a vertical position necessary for perching, pressing its fuselage flat against the pole. A latch system releases tension from the wings, allowing torsion springs to wrap them around the pole, securing the UAV in place without active control.
This innovative approach could open new possibilities for drone applications in both urban and natural environments, leveraging nature’s strategies for efficient and effective perching.
“Our approach avoids adding dedicated perching feet structures, which would increase weight and complexity,” the paper explains. “Instead, we leverage existing UAV elements with a dual-use strategy. This includes using front limbs (wings) to tightly hug poles, keeping the center of mass close to minimize the pitch-back effect. Additionally, the long tail, effective in nature for landing and resting, enhances stability.”
In experimental tests, the unmotorized PercHug was hand-launched towards trees. Initially, the drone often slid down after wrapping its wings around the trunk. Installing removable hooks helped address this issue, leading to more successful perching.
The researchers believe their project sets the stage for advancing perching technologies, opening doors for versatile robotic systems tailored to various applications. These include inspecting tall or complex buildings safely, assessing challenging infrastructure like cell towers, performing on-demand surveillance or environmental monitoring, and studying wildlife behavior for conservation efforts.
Looking ahead, team member Mohammad Askari shared, “Our current platform is fully passive, limiting its capabilities. Our goal is to develop a motorized follow-up platform based on PercHug. This would demonstrate climbing and relocation capabilities at perched locations for inspection purposes, followed by detachment and continued flight to complete missions.”