The U.S. Army is training troops to use 3D printers to build concrete barracks, or to use drones to gather intelligence in contaminated spots that might be dangerous for soldiers.

Or, scanner technology currently used by the law enforcement agencies to document crime scenes in 3D could someday be used on the battlefield to make maps with previously unthinkable levels of detail.

Some of that technology is being tested at Fort Leonard Wood, which showed off the machines to journalists this week. It's part of a program the Army calls the Maneuver Support, Sustainment, Protection, Integration Experiment. The goal is to allow service members who might use the devices during deployments to test them and have input before the technology is declared field-ready, The Springfield News-Leader reported .

The strategy makes the military more efficient and saves money, said Mike McCarthy, deputy to the commanding general for the Maneuver Support Center of Excellence at Fort Leonard Wood.

"Using this process takes 40 percent less time from concept to fielding new technology than traditional methods," McCarthy said. "It also has a significant cost savings. You don't have to go back and fix it after fielding."

And soldiers, who often have to adapt to survive in the field, can offer ideas for technology that might never occur to engineers in a design-lab setting, he said.

Megan Kreiger, a U.S. Army Corps of Engineers official based in Champaign, Illinois, demonstrated a 3D printing technology called ACES: Automated Construction of Expeditionary Structures. It is the size of a large garden shed and can use concrete to build a barracks hut to house 20 soldiers in about 21.5 hours, she said.

Before ACES can be used in war, Kreiger said a version needs to be developed that could survive various weather conditions and be sturdy enough for transportation. The Army and the Corps also want to develop ACES technology that would allow soldiers to print out structures using dirt found on-site to form bricks rather than importing sacks of cement powder into a deployment area.

Another technology at the demonstration was two types of drones outfitted with technology the Army calls "C-SIRP." They contain miniaturized sensors mounted on the underside of quadcopter drones, which could be deployed ahead of soldiers. One was called Deep Purple, designed and made by the government, and InstantEye, manufactured by Physical Sciences Inc.

The sensors can detect chemical contamination and other conditions in zones. Fiona Narayanan, who has worked on Deep Purple, said the goal was to use existing technologies to help commanders make better decisions more quickly, reducing the risk to human life.

"This negates us going to any given bad place," said Staff Sgt. Nathaniel Boe, one of the service members testing C-SIRP. "It keeps us out of danger."

Another technology was a laser scanner, called FARO Focus, which is currently used by law enforcement agencies such as the FBI and New York City police department, said special agent Edward Wheeler. They can make 800,000 measurements in 3D per second. That allows law enforcement officers to record data at a crime scene in about 40 minutes rather than taking two or three hours to measure everything by hand.

Staff Sgt. Christopher Schultz said that FARO Focus lasers are not yet used for war but they could be valuable for 3D mapping or route-planning, for example. The devices can be mounted on robots or vehicles and can make 3D images while on a truck moving at 55 mph or in complete blackness.