U.S. engineers say their wearable mapping system can create physical maps of locations where GPS is not available, such as in underground areas and on ships.

Developed by the Applied Physics Laboratory at John Hopkins University, the Enhanced Mapping and Positioning System captures a floor-plan-style map of an area traversed by a person carrying the portable backpack system, as well as 360-degree photos and sensor readings of the area using a combination of lasers and sensors.

The system based on algorithms once developed for robots -- which are not practical in some environments -- has a built-in allowance for normal human movement like walking, a Johns Hopkins release reported Wednesday.

Designed mainly to detect and map environmental threats on ships and in other tight, enclosed locations, EMAP can associate critical environmental data, such as radiation or radio frequency signal levels, with map locations.

"EMAPS virtually takes pictures with every step," researcher Jason Stipes said. "Using this technology, we can map almost every nook and cranny of targeted locations, capture that intelligence, and store it. Sensors can also detect threats, such as radiation or chemicals, and include them in our map."

In testing EMAPS has collected of mapping data from a wide variety of GPS-denied environments including ships, underground storage facilities, Army training areas and buildings such as the Smithsonian Natural History Museum, Stipes said.