The explosive detector uses a wireless sensor to detect trace amounts of ammonia, a key chemical used in improvised explosive devices (IEDs), the deadliest killer of U.S. troops in Iraq and Afghanistan. 

The detector has the potential to be deployed cheaply and broadly in warzones as the sensor and its antennae can be printed on paper-like material from an inkjet printer. In addition, the device has low power requirements allowing it to operate for several days when attached to long lasting, thin-film batteries. 

The military hopes to eventually scatter large amounts of these sensors downrange to help thwart the threat of IEDs. 

“IEDs are a very pressing problem. A lot of military personnel and civilians are losing their lives,” said Krishna Naishadham, the principal research scientist, who is leading the team of Georgia Tech researchers. “The sensors being used are expensive or require special training. We had the idea of producing something low-cost, so you could spread these in the field.”

The integrated sensors are capable of detecting trace elements of explosive materials from as far as sixty-five feet away. In addition, the sensors can be used to check shipping containers for explosives as well as at airports and border security checkpoints. 

Currently, the sensors still have a few kinks that need to ironed out before they can be deployed. For instance, detecting ammonia alone would yield far too many false-positives as the chemical is found in many other sources like runoff from fertilizer. 

“Two important things need to be done before this technology is made ready for field applications,” Naishadham said. “You want to maximize the sensitivity while filtering responses to remove naturally occurring gases.”

Researchers also hope to improve the sensors to detect other gases so they can be deployed in a variety of settings like in hospitals to detect biological or environmental contamination. 

As of now, the sensors still require specialized ink-jet printers that can create a specific pattern on photographic paper, so they are only practical in a laboratory setting. 

Naishadham believes full-scale production of sensors is still roughly two to three years away.

 “It’s low-cost, but not low-manufacturing yet,” he said.