In the waning days of 2009, Dennis Clements was a long way from home. The Missourian had traded the Midwest's cold winters for a small island near the eastern bounds of Puerto Rico.
Or at least, that's what he thought.
Clements' 34-foot (10-meter) sailboat became stranded in the North Atlantic Ocean long before he reached his island destination. For four days, gale-force winds pushed the boat -- and its captain -- to the limit, nearly drowning them both on Dec. 26.
In one swift move, winds and waves capsized the boat and dumped Clements into the icy water. He watched as the boat popped back up, righted itself, caught air in its sails and moved impossibly out of reach.
It was dark. He was 250 miles (402 kilometers) out at sea. And hope was fading fast.
Clements was sure he was a dead man.
Then a decision he'd made four years earlier saved his life. Clements had purchased an Emergency Position Indicating Radio Beacon (EPIRB) and affixed it to his sailboat. When the boat became waterlogged, the beacon began to transmit a distress signal to weather satellites operated by the National Oceanic and Atmospheric Administration (NOAA). These satellites, outfitted with NASA-developed repeaters, relayed the distress signal back to NOAA ground control where it was put in the hands of the Search and Rescue Satellite-Aided Tracking (SARSAT) program, which determined the distress signal's location and relayed the information to the U.S. Coast Guard.
While Clements believed he was experiencing his last moments on Earth, his rescue was already underway. The U.S.S. Dwight D. Eisenhower was the only rescue-capable vessel within 100 miles (161 kilometers) of Clements and immediately dispatched a helicopter and crew. Within four minutes of finding Clements, the Navy seaman aboard had rescued him [source: NASA].
The technology that made Clements' rescue possible relied on low-orbiting weather satellites that could ping a signal back to the responder on a boat. Although this technology can produce obvious results -- namely, the rescue of a person in distress -- it still has room for improvement. Advanced search and rescue technology trades time-consuming and general distress coordinates for immediate, precise data. And it works on land, in air or at sea, in urban or rural areas, and in the wake of earthquakes or tsunamis.
Taking 'Search' Out of the Equation
The NASA-developed Search and Rescue Satellite-Aided Tracking (SARSAT) program that in 2009 helped rescue Clements was responsible for saving 194 other lives that year -- and continues to be effective. In 2012, it prompted the rescue of 263 people in the United States [source: NOAA].
In 2010, however, NASA began rolling out Distress Altering Satellite System (DASS) technology for search and rescue. Unlike SARSAT, the DASS doesn't use NOAA weather satellites. Instead, its distress signal repeater connects to U.S. Air Force Global Positioning System (GPS) spacecraft orbiting Earth. This hook-up creates two important improvements: Distress signals -- and their origins -- can be identified faster and more precisely. For example, DASS technology can precisely locate a distress signal within just a few minutes instead of the hour or more SARSAT may require. According to NASA, the DASS search and rescue technology will be fully operational by 2015 and linked to all the Air Force's Block III GPS satellites. It's expected to speed rescues not only for stranded boaters, but lost aviators and hikers, too [source: NASA].
Not everyone who needs rescue happens to be carrying a satellite-linked rescue beacon, though. What about survivors of tornadoes, earthquakes, hurricanes or tsunamis? Natural disasters like these can strike quickly and leave hundreds (sometimes thousands) in need of rescue.
Technical search equipment is a standard part of most search teams' arsenals and usually includes electronic listening devices (to hear signs of life), viewing devices like fiber-optic cable cameras and GPS receivers with mapping software [source: Stevens].
In addition, specially trained dogs can go into spaces too tight or unstable for humans, which is an important distinction when survivors are trapped beneath rubble or debris. And, because humans constantly slough off microscopic particles that act as a scent fingerprint carried by the wind, rescue dogs don't even need to track a fresh scent on the ground. This is known as "air scenting" and is an effective search technique that's been used to discover lost hikers, locate survivors of train and plane crashes and find skiers buried in avalanches. The dogs and their handlers are assigned specific geographical sections to investigate, and if a dog picks up a human scent, it alerts its handler with a bark [source: Lewis, NASAR].
Search and rescue dogs can get the job done, but they may have competition from another -- very tiny -- member of the animal kingdom.
The Future of Search and Rescue Technology
The next time you notice an anthill, don't squash it. It could just be the key to a future search-and-rescue operation. Researchers have been studying fire ants and their ability to speedily dig through all sorts of materials -- from soil to glass beads. No matter what the material, the ants' digging remains the same. They create tunnels with a diameter that matches the length of their bodies; this ideal size allows for two-way ant traffic while keeping tunnel walls within easy grasping distance. These tunnels -- and their creators -- could offer the key to more effective search and rescue robots.
Currently, search and rescue robots are built like miniature tanks. Boxy and inflexible, the robots work best when traveling in a straight line on level terrain. But what if scientists could take their cues from fire ants and figure out a way to make an agile robot that can enter underground chambers or navigate impromptu tunnels caused by falling debris? Thanks to inspiration taken from snakes or caterpillars, researchers almost did.
A snake robot that could wiggle its way through a collapsed structure and a caterpillar robot that could vibrate into disaster-created tunnels worked admirably in laboratories, but not real life. When tested after a building collapse in Cologne, Germany, both robots failed. They were either too large to fit beneath the rubble or couldn't be operated from a safe distance. The robots required complex machinations to move, which translated into more opportunities for parts to break down. Plus, the robots were expensive to build and operate. Researchers have to figure out how to combat the robots' substantial energy drain in potentially remote environments [sources: Fecht].
In 2012, however, rescuers came up with a potentially powerful combination when they devised a way for rescue dogs to deploy snake robots. During training exercises, a search and rescue dog equipped with a snake robot finds a survivor, then barks to alert its handler. This bark activates the robot, which enters spaces too small or dangerous for the dog to fit. The snakebot then relays video and audio back to rescuers [source: Boyle].
Whether it means locating a GPS-equipped distress signal or using a snakebot-toting dog, search and rescue operations have entered a digital age.
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Author's Note: What technologies have made search and rescue easier?
I've never been lost in the wilderness, thank goodness. Or required rescue from a stranded boat. Or (more likely) tornado debris. But if I did, I think I'd be so grateful to see a rescue robot that I wouldn't even mind if it looked like a snake. Whatever the form, the ideas brewing among researchers and the rescue community seem to be good ones. After all, there has to be a more effective way to rescue people than flashlights and a hunch, right?
- Boyle, Rebecca. "Rescuing Disaster Victims with Snake Robots Deployed by Dogs." Popular Science. Jan. 17, 2012. (Sept. 6, 2013) http://www.popsci.com/technology/article/2012-01/video-dog-deployed-snakebots-are-future-disaster-rescue
- Fecht, Sarah. "Fire Ants Could Inspire the Next Rescue Robots." Popular Mechanics. May 21, 2013. (Sept. 6, 2013) http://www.popularmechanics.com/technology/engineering/robots/fire-ants-could-inspire-the-next-rescue-robots-15498631
- Lewis, Tanya. "How Rescue Dogs Hunt for Tornado Survivors." Live Science. May 21, 2013. (Sept. 6, 2013) http://www.livescience.com/34552-rescue-dogs-hunt-for-tornado-survivors.html
- NASA. "Sailor Reflects on NASA Technology That Saved His Life." May 24, 2010. (Sept. 6, 2013) http://www.nasa.gov/topics/technology/features/search-rescue2010.html
- NASA. "Taking the 'Search' Out of Search and Rescue." Sept. 2, 2010. (Sept. 6, 2013) http://www.nasa.gov/centers/goddard/news/features/2010/search-and-rescue.html
- NASAR. "Canine Fact Sheet." (Sept. 6, 2013) http://www.nasar.org/page/49/Canine-Fact-Sheet
- NOAA. "Welcome to SARSAT." (Sept. 6, 2013) http://www.nasa.gov/centers/goddard/news/features/2010/search-and-rescue.html
- Sandoval, Greg. "Lessons Learned From Kim Tragedy." Dec. 6, 2007 (Sept. 12, 2013). CNEThttp://news.cnet.com/Lessons-learned-from-Kim-tragedy/2100-1028_3-6221778.html
- Stevens, Mark. "How Emerging Technology Can Assist Urban Search and Rescue." Emergency Management. Jan. 24, 2013. (Sept. 11, 2013) http://www.emergencymgmt.com/disaster/Emerging-Technology-Urban-Search-Rescue.html