The U.S. military has tried countless ways to fight the use of improvised explosive devices in Iraq and Afghanistan.
Here’s another one: Inkjet printers.
Researchers at the Georgia Institute of Technology have developed a prototype wireless sensor that can be printed on paper or similar material using standard inkjet technology. The device employs carbon nanotubes and can detect trace amounts of ammonia, an important ingredient in explosives. The special “inks” consist of silver nanoparticles in an emulsion that is printed at low temperatures.
Scientists also have been able to print antennas that are required to communicate information from the sensor so nearby personnel can be alerted when ammonia is detected. Their work is based on the same inkjet technique that is used to produce radio frequency components, circuits and antennas.
“We are focusing on providing standoff detection for those engaged in military or humanitarian missions and other hazardous situations,” said Krishna Naishadham, a principal research scientist leading the work at the institute. “We believe that it will be possible, and cost-effective, to deploy large numbers of these detectors on vehicles or robots throughout a military engagement zone.”
Inkjet printing is more convenient and costs less than other sensor technologies, researchers said. With the right inks, a printer can be used almost anywhere to create custom circuits and components, they said.
The sensors can be printed on heavy photographic paper, flexible fire-resistant polymers or even plastic like that used in soda bottles. They could be powered by thin-film batteries, solar cells or power-scavenging and energy-harvesting techniques. Scientists also are looking into ways to make the sensors operate passively without the need for any power.
The current project builds on an effort last year, which saw scientists print an ammonia sensor and antenna on paper. The difference is that the newest sensor is much more sensitive to miniscule concentrations of ammonia, researchers said.