Tiny unmanned vehicles may one day be able to swarm over, under, and through hurricanes to help predict the strength and path of storms.
The autonomous craft—some fly and others dart under the waves—can spy on hurricanes at close range without getting blown to bits, while sensors onboard collect and send in real time the data scientists need to predict the intensity and trajectory of storms: pressure, temperature, humidity, location, and time.
“Our vehicles don’t fight the hurricane; we use the hurricane to take us places,” says Kamran Mohseni, professor in the department of mechanical and aerospace engineering and the department of electrical and computer engineering at the University of Florida.
The aerial and underwater vehicles, just six inches long and about the weight of an iPod Nano, can be launched with commands from a laptop hundreds of miles from the eye of a hurricane. Mohseni and colleagues use mathematical models to predict regions in the atmosphere and ocean that can give the vehicles a free ride toward their destination.
Once in the vicinity, they can be powered off to wait for a particular current of wind or water. When they detect the current they need for navigation, they power back on, slip into the current, then power off again to conserve fuel as the current carries them to a target location. In essence, they can go for a fact-gathering ride on hurricane winds and waters.
The devices are a departure from current technology, which uses hurricane reconnaissance aircraft to punch through a storm’s eye wall and release dropsondes, sensors that free-fall and might or might not collect helpful data. Underwater data are even more difficult to collect, although just as important, considering that the warm, moist air on the ocean surface provides fuel for hurricanes.
The new vehicles, which can be launched hundreds at a time, also reduce the cost of hurricane reconnaissance.
“If you want to blast through a hurricane, you have to build a bigger airplane,” Mohseni says. “(The military) asks for a Batman airplane, a super-duper aircraft that could do everything. But what if you lose one of these super-duper airplanes?
“We are going the opposite direction. We don’t have anything that is super duper. We have cheap sensors, but with a lot of them you can significantly increase the accuracy of your measurements. You get super duper on an aggregate level.”
The prototypes are about $250 each and are too small and lightweight to cause damage when they hit something, a big consideration in hurricane-force winds and waves. A landing strip to test the aerial vehicles isn’t necessary, Mohseni just tells them to crash, picks them up, and flies them again. The carbon fiber shell of the aerial vehicles is wafer-thin but resilient.
With proper funding, the vehicles could be tested in a real-world hurricane in two or three years.
In instances where many are lost—as in a hurricane—the data gained outweighs the cost of the lost vehicles, Mohseni says. Production costs would drop if the vehicles were mass-produced.
The vehicles also are smart. A cooperative control algorithm allows them to form a network and learn from the data they take in, for example, by adjusting their course when needed. This feature makes them useful for applications beyond hurricanes.