The submarine super plane can fly in less than a second
Robots have traditionally been purpose-built to perform a very specific task, but researchers at Beihang University are taking an entirely different approach with New robotic drone It can operate underwater just as easily in the air and features a nature-inspired trick to increase its range.
When you think of robots, one of two versions probably comes to mind: the highly capable humans promised by science fiction, or the reckless articulated arms that perform repetitive tasks in factories. This latter approach is sort of the one we’ve been practicing for decades, but as technology slowly catches up with the imaginations of science fiction writers, robotics designers have begun to develop mechanisms capable of performing a variety of tasks. actions. Boston Dynamics spotHe, for example, uses four dog-like legs to navigate various terrains and perform many different tasks, including protecting the ruins of Pompeii at night and creating detailed 3D maps of areas that are difficult for humans to visit.
An adaptive approach makes it easier for companies or research institutes to justify the high cost of the robot, but what Beihang University’s Biomechanics Lab and Soft Robotics Lab have created is truly unique. Even with highly articulated legs, Boston Dynamics remains limited to ground missions. This new drone can perform missions underwater, in the air, or both, with no modifications needed in between.
For most quadcopters, landing on water means the pilot will have to get out to rescue them (and then replace most of their electronics). This plane is different. It is completely waterproof and features a set of self-folding propellers that collapse when operating at low underwater speeds to efficiently maneuver the drone while submerged. Then it automatically extends when the drone comes out of the water and into the air. Researchers have optimized the drone’s performance so that the transition from water to air takes about a third of a second, and like a pod of dolphins jumping out of the water, the drone is able to repeat transitions between water and air, performing seven of them in a row during testing in about 20 seconds.
As with any electronic device, a robot’s autonomous capabilities are often limited by the capacity of its batteries, and this is especially the case for flying drones that rely on four electric motors that constantly spin to stay aloft. In the lab, you’ll often see advanced robots attached to cables that provide an uninterrupted power source, but this isn’t a great option for robots designed to explore the depths of the ocean or collect aerial data, or both, in this case. .
To dramatically increase the range of this drone and to help save battery power when traveling to and from a mission site, researchers gave it an additional upgrade inspired by the remora fish, better known as the suckerfish, which uses an adhesive disc on top. from its head to temporarily attach itself to other underwater creatures in order to hitchhike and save energy.
Drones that can land in order to make targeted observations while preserving battery life are not a new idea, but like robots in a factory, they usually use mechanisms adapted to specific surfaces, such as jointed claws holding a branch Or gecko-inspired sticky feet that stick to walls. For a robotic drone designed with flexibility in mind, researchers wanted a more versatile way to attach itself to a variety of surfaces: wet, dry, smooth, rough, curved, or even those that move underwater, where forces water shear require adhesion. . Too powerful.
Remora’s Adhesive Disc was the perfect solution, as it includes a built-in overhang that allows it to stick to surfaces even with partial contact. Two years ago, Li Wen, one of the researchers and author of the article published today, was part of another research project at Beihang University that reverse-engineered the actual operation remora discus.
This research found that remora fish adhere to surfaces like a suction cup, with a flexible oval edge of soft tissue that creates an airtight seal. When water is forced out of the space between the remora and its host, the suction holds it in place. The surface of a remora disc is also covered with edges aligned in columns and rows called lamellae (similar to the bumps you can feel on the roof of your mouth) that can be stretched by muscle contractions to engage the small tendons that retain more of the upper part of the mouth. Host. These lamellar flanges also help create smaller vacuum compartments that keep them sealed even if the larger disc lip does not. Unlike a suction cup, which releases its grip on a smooth surface when a small part of its edge is lifted, a remora will hold its own.
The team was able to create a synthetic version of the remora’s suction disk through a four-layer approach. They paired a super-elastic layer on top with stiffer structures underneath, as well as a layer with a network of tiny channels that can be inflated when filled with fluid, replacing living muscle tissue as a way to Engage lamellar structures to increase suction.
The suction mechanism mounted above the submersible plane allows it to stick to a variety of surfaces, even if they are rough to the touch, not completely flat, or have a smaller surface area than the suction mechanism. Like a remora, the drone could, at least in theory, find itself an underwater host (not immediately frightened by its spinning propellers) and suspend itself in free flight, requiring only the suction mechanism to operate, and the minimum consumption of batteries on board. The same can be done in the air, although the challenges of successfully attaching a drone to another aircraft would be great, even something as slow as a glider has a minimum speed of 40 mph: a difficult moving target .
The most reasonable use of the vacuum mechanism is to temporarily position the drone somewhere with an ideal vantage point for long-range observations. Instead of relying on its four motors to maintain a specific position underwater while battling moving currents, the drone can stick to a rock or piece of wood and turn off its motors, while continuing to use its sensors and cameras. The same can be done above the waterline, by flying the drone and sticking to the side of a tall building or below a wind turbine nacelle, taking measurements and collecting data. other data without using its motors that drain the battery. It’s a battery technology solution that’s still incredibly limited and avoids having to repair the batteries themselves.