Engineers from the Singapore University of Technology and Design have created a nature-inspired drone that can break apart into five smaller drones with autorotating wings that allow them to slow their rate of decent and land safely. The idea is that the drone is used for a one-way trip, with each of the five blades carrying a payload. When the drone is within distance of its destination, the five wings detach from the collective and spiral down slowly and safely, delivering their payloads on target like seed pods from a maple tree.
Samara fruit pods can have one or more wings that allow them to spin and fall to the ground in a somewhat controlled manner, which provides the seeds with a certain level of protection. The researchers added a flap to their wing design that when actuated, offers a limited degree of controllability to help get the wing to a certain point on the ground, or close to it.
In a recent paper entitled “Dynamics and Control of a Collaborative and Separating of Samara Autorotating Wings,” the engineers describe how the drone came to fruition. Four balsa wood wings are outfitted with servo, LiPo battery, and receiver attached to a 3D-printed body, while a fifth is equipped with a 3-axis magnetometer, a Teensy 3.5 board, a GPS module, and a Pixracer controller.
Each wing connects together to form a collective that spins for long-duration flight. When it reaches its destination, the servos engage a separation mechanism (small saw), cutting a rubber band holding them together, and break apart and fall safely to the ground. The team envisions their drone delivering small payloads, such as sensors or medical supplies to people in remote locations.