October 16, 2013
Drones Help Create Detailed Maps Of Coral Reefs
[ Watch the Video: Coral Reef Mapping With The Help Of Drones ]
Brett Smith for redOrbit.com - Your Universe OnlineThe War on Terror may have given unmanned drones a bad name, but a research team from Stanford University just might be able to rehabilitate that image. Ved Chirayath, an aeronautics researcher, and Steven Palumbi, a marine biologist, have started using an unmanned drone and cutting-edge computer software to map and measure centuries-old corals.
Equipped with several cameras, the Stanford drone is able to create detailed images of coral reefs from up to 200 feet in the air.
“Until now the challenges have been too high for flying platforms like planes, balloons and kites,” Palumbi said. “Now send in the drones.”
Images captured by the drone are analyzed using software designed by Chirayath which boosts image resolution and removes distortions caused by water movements. The Stanford researchers are also imaging the reefs from beneath the surface of the water using a 360-degree camera. The result of the two sets of image data is a centimeter-scale optical aerial map and stunning panoramic photographs of coral heads.
Chirayath also works for NASA’s Ames Research Center, which first developed the reef project’s software called Fluid Lensing. NASA had hired the engineer to create a methodology that would capture satellite imagery of natural features on Earth in addition to targets in space. After developing the software, Chirayath began looking for other applications and devised a camera-equipped drone after learning about widespread coral bleaching and a lack of accurate reef maps.
“I was inspired by the way the human eye works in conjunction with the brain to try to resolve an obscured image,” Chirayath said.
The engineer compared his coral images to sketchbook drawings of a person behind a waterfall. The person’s face might be distorted in a photograph, but a sketch artist could painstakingly recreate the face over time.
“It’s an ability to rapidly assimilate a vast amount of data and, in effect, see through strong optical distortions" served as an inspiration, he said.
After learning about Chirayath’s work, Palumbi invited him on a research trip to study shallow-water reefs off Ofu Island in American Samoa.
“The lensing takes a huge problem in looking through the surface of the water and turns it into an advantage,” Palumbi said. “It not only removes the ripples but uses their magnification to enhance the image.”
The two scientists used their novel system to study what they called the “Village of Elders,” a stretch of back-reef lagoon that serves as an ideal nursery for long-lived corals.
“These corals are time machines that were living before European culture discovered the Samoan islands,” Palumbi said. “What do they have to tell us about that long-ago time? What do they tell us about the likely future?”
Palumbi said he plans to use drone-generated maps to determine the location and size of corals in the Ofu reefs. He plans to then use the drone-captured images to better understand climate change’s effects on coral. By comparing a water temperature map on a survey of the oldest corals, the marine biologist said he hopes to learn about the conditions that help support coral longevity.