Researchers at Arizona State University unveiled a look at the SoBAR Drone, which is an experimental iteration of a classic drone that is highlighted by its inflatable body. Due to this structure, the drone is able to bounce off of obstacles and even cling onto them depending on the circumstance.
The SoBAR drone is short for ‘soft-bodied aerial robot. It features the same electronic elements as a regular drone but the key difference is the frame. It is made from a high-strength polyurethane-coated nylon fabric material, which is able to inflate on command.
“We see drones used to assess damage from high in the sky, but they can’t really navigate through collapsed buildings,”
says Wenlong Zhang, an associate professor and robotics expert in the Ira A. Fulton Schools of Engineering at Arizona State University.
“Their rigid frames compromise resilience to collision, so bumping into posts, beams, pipes or cables in a wrecked structure is often catastrophic. They don’t recover; they crash. Drones need to physically interact with their surroundings to accomplish a range of tasks. A soft body not only absorbs impact forces to provide collision resilience; it also offers the material compliance necessary for dynamic maneuvers such as perching.”
Zhang says aerial drones need to endure knocks and jolts to achieve their potential for search and rescue operations. Toward that end, he and his lab team have designed and tested a first-of-its-kind quadrotor drone with an inflatable frame. Uniquely, it’s stiffness is tunable or adjustable to absorb and recover from unexpected taps and thumps. The results of their work have been published in the journal Soft Robotics.
“We need to change our focus on avoiding environmental contact. Drones need to physically interact with their surroundings to accomplish a range of tasks,” Zhang says. “A soft body not only absorbs impact forces to provide collision resilience; it also offers the material compliance necessary for dynamic maneuvers such as perching.”
Perching is an example of controlled collision. Birds technically collide with tree branches or other structures as they land and perch. Their compliant joints and soft tissues absorb the impact force, and a passive locking mechanism in their feet enables them to grasp onto irregular surfaces without using muscular energy to hold them in place.
Zhang and his team drew inspiration from this avian model to design a hybrid fabric-based bistable grasper for their new aerial drone. Bistable means it has two unpowered resting states: open and closed. It simply reacts to the impact of landing by snapping closed and securely gripping onto objects of various shapes and sizes.