Researchers at EPFL have developed an origami-like drone that is sufficiently flexible to absorb shocks without breaking before returning to its original shape. This innovative type of drone, inspired by insect wings, has the advantages of both flexible and stiff structures.
An origami-like drone developed at EPFL is flexible enough to absorb shocks without breaking before returning to its initial shape. This new type of drone, which was inspired by insect wings, draws on the advantages of both stiff and flexible structures. (Video credit: EPFL)
In the recent past, robotics experts have simulated the traditional Japanese practice of origami and developed flexible, lightweight, and highly innovative drones and robots. Two kinds of origami-inspired structures have emerged: rigid structures with a specific weight-bearing capacity but that break when that capacity is exceeded, and flexible but resilient structures without the ability to carry that much load.
Scientists from EPFL have applied the thing that they observed about insect wings and have created a hybrid origami drone that can be flexible or stiff based on the circumstances. When airborne, the structure is sufficiently stiff to carry its own weight and endure the thrust of the propellers. However, in case the drone runs into something, it turns flexible to absorb the shock and hence minimize any damage. This study, which is ongoing in Dario Floreano’s Laboratory of Intelligent Systems, has been reported in the Science Robotics journal.
The resilience of the drone is the result of a unique combination of elastic and stiff layers. An elastomer membrane is stretched and subsequently sandwiched between rigid plates. If the system is at rest, the plates stay tight together and provide the structure its stiffness. However, upon applying sufficient force, the plates move apart and the structure can bend.
“When we make a drone, we can give it specific mechanical properties,” stated Stefano Mintchev, the lead author of the study. “This includes, for example, defining the moment at which the structure switches from stiff to flexible.” Moreover, since the drone intensifies elastic potential energy upon being folded up, it has the ability to automatically unfold when instructed so.
Structures that are flexible and stiff at the same time have several other prospective applications as well. During the development of the drone, the scientists used the same technology to develop a soft-touch gripper that softens upon reaching a specific level of pressure to ensure that it does not break the object that it picks up. This also suggests that it cannot pick up a load exceeding its capacity.
“The current trend in robotics is to create ‘softer’ robots that can adapt to a given function and operate safely alongside humans. But some applications also require a certain level of rigidity,” stated Floreano. “With our system, we have shown that you can strike the right balance between the two.”