Maple seeds. Most people admire them for being pretty and delicate and for twirling like ballerinas when they float to the ground in fall. But this graceful dance obscures a simple fact: they are efficient flying machines.
This week, Lockheed Martin is debuting an unmanned military drone that could be useful for information-gathering based on these silent, strong, one-winged, helicopter-like flyers.
A foot long, the SAMARAI (after samara, the name for maple seeds) also has one wing and flies with a cyclic lift motion like a helicopter. It has two moving parts and a camera and can be controlled remotely or with an app on a tablet computer. It will be one of many new unmanned vehicles on display this week at the convention of the Association for Unmanned Vehicle Systems International in Washington, D.C.
How samara fly
In a manner similar to insects, hummingbirds and bats, maple seeds fly by creating a vortex over the leading edge of the wing. Reducing the pressure above the wing’s surface like this creates a mini sideways tornado and the low pressure pulls the wing up, giving it twice the lift it would normally have.
Because of this action, when maple seeds swirl to the ground, they go much more slowly and land farther from the tree than they otherwise would.
Both the military and police could use SAMARAI. Officers could throw the drones like boomerangs to photograph what is around the next corner or inside a building and report back. Troops could also use them to get ground-level images from airplanes in addition to the aerial images typically used now.
They improve upon drones currently used by the military in that they can hover in place like helicopters and take off vertically — an advantage in tight spaces.
They could one day come in different sizes and be produced cheaply with 3D printing.
Watch the video below (from 2010) to see the SAMARAI be launched like a boomerang, take off vertically and land in a specific spot:
This video simulates the graceful motion a maple seed in flight:
photo: Kobako, Wikimedia