NASA Technology

Late on a sweltering morning in July 2016, David Lewis Jr. crawls into a concrete tube in a heap of rubble amid what used to be a Northern Virginia prison complex.

NASA has long experience analyzing weak signals to detect slight physical movements, cancelling out huge amounts of noise. Here, Doppler and range tracking data from three Mars orbiters were used to detect slight movements in their paths that indicate gravity fluctuations, allowing scientists to construct a gravity map of the entire Red Planet.

Only the toe of Lewis’ shoe is visible. As bystanders look on, R4 Inc.’s new FINDER device—that’s Finding Individuals for Disaster and Emergency Response—is trained on the scene and begins quietly clicking away, calibrating its radar to the objects and environment, before entering detection mode.

Within about three minutes of the radar’s initiation, it reports the results of its search on a handheld graphical user interface: “FINDER detected one victim,” the screen reads, above a high-definition photo of the concrete jumble where it spotted Lewis. It has also taken an infrared image to capture any possible body heat signature, and Lewis’ breathing and heart rates are reported.

Shawn Crockett, vice president of business development at R4, where Lewis is a project manager, notes that his colleague’s heart rate was higher than in another trial moments before.

“It was a little hot in there—there’s no breeze,” Lewis explains.

Using FINDER is still not an exact science: during the first test, the device mistook Lewis for two people. But even as it continues to improve, its lifesaving potential is already clear and has even been proven in the field, where it has been used to find earthquake victims trapped under rubble.

In the case of the double hit on Lewis, Crockett says, “For us it doesn’t matter. If we think there’s a life in there, we’re going in.”

The Edgewood, Maryland-based company is developing a line of such remote sensing devices to aid search and rescue teams, based on advanced radar technologies developed by NASA and refined for this purpose at the Agency’s Jet Propulsion Laboratory (JPL).

NASA has long analyzed weak radio signals to identify slight physical movements, such as seismic activity seen from low-Earth orbit or minor alterations in a satellite’s path around another planet that might indicate gravity fluctuations, explains Jim Lux, JPL’s task manager for the FINDER project. However, to pick out such faint patterns in the data, these devices must cancel out huge amounts of noise. “The core technology here is measuring a small signal in the context of another larger signal that’s confusing you,” Lux says.

In the early 2000s, the Department of Defense approached JPL wondering about the possibility of using remote sensing to determine whether there were troops alive on a battlefield and to take remote biomedical readings. Some work was done, and Lux says the latter application could still be of interest for monitoring astronauts in the International Space Station, for example. But funding dried up.

The work, however, was not forgotten, and years later, members of the Department of Homeland Security (DHS) Science and Technology Directorate approached JPL, recalling that engineers there had worked on remotely detecting a heartbeat. The Federal Emergency Management Agency (FEMA), which falls under DHS, wanted such a device for locating trapped survivors. With DHS funding, Lux’s team set about developing the FINDER prototype.

Being NASA engineers, they were well-versed in the art of designing and packaging small, low-energy, rugged hardware, which the units required. Identifying working hearts and lungs by reflected microwave radar was trickier, but they had picked out slight movements from overwhelming data streams before. “This is a combination of a bunch of things NASA has been doing,” Lux says. “A lot of the pieces of this existed in some form or another.”

Earthquakes are the deadliest of natural disasters, crushing tens or even hundreds of thousands of people under fallen buildings. Inevitably, many survivors are trapped alive but are difficult to find under the rubble. Engineers at NASA’s Jet Propulsion Laboratory (JPL) used their experience with analyzing weak signals to develop a technology that uses radar to identify unseen people by detecting their breathing and heartbeat. A company called R4 Inc. licensed and developed the technology and is now making sales to government entities in the United States and abroad. Image courtesy of Voice of America

Once the engineers were able to identify a heartbeat, they had to further refine signal-processing algorithms to distinguish a human heartbeat. For example, even a large dog has a faster heart rate and, especially, a faster breathing rate than a human, Lux explains. And to pick out multiple victims, the device had to be able to recognize the rhythms of distinct pairs of heart and breathing rates. This is possible because the heart speeds and slows with each breath, says Lux.

FINDER can detect up to five separate victims in a given area.

Technology Transfer

R4’s founders, two U.S. Army veterans, came across an online article about FINDER several years ago, after JPL had developed a prototype and DHS had tested it. The California Institute of Technology (Caltech), which manages JPL, was looking for a company to commercialize the technology.

R4 had to do quite a bit of its own development to make FINDER functional, although JPL engineers have continued to partner with them. Though the units are now available for sale, the team continues to improve the technology.

R4 reached out, and before long, Caltech had awarded licenses for FINDER to R4, as well as the company SpecOps Group Inc., which is working to commercialize its own version of the technology.

Over the next couple of years, R4 developed lighter-weight housings for the technology, made it more rugged, and improved the graphical user interface. “We improved all those things so it’s something a first responder could use in a real-world situation,” says Lewis.

A big test and major success came when a 7.8-magnitude earthquake rocked Nepal just northwest of its capital of Kathmandu in late April 2015, killing more than 8,500 people. Lewis’ father, one of R4’s founders, arrived four days after the quake with two FINDER prototypes and joined search and rescue crews. Using the devices, rescue workers in the hard-hit village of Chautara located two men trapped beneath the remains of a textile factory and two more pinned under the debris of another building.

Upon their discovery, all four men, who had been buried in rubble as deep as 10 feet, were rescued. They all survived.