Ground robots coming of age with expanding missions.

• Author: Jean, Grace V.

* Bomb disposal technicians embedded with special operations forces increasingly are using their ground robots to help conduct raids and accomplish missions beyond their assigned seek-and-destroy duties. Their resourcefulness is spreading to their peers throughout the conventional forces as well.

As troops apply explosive ordnance disposal robots to more tasks, researchers and engineers are advancing artificial intelligence behavior algorithms, creating new controllers and developing kits to automate manned platforms. Their efforts will make it possible for robots to sneak up autonomously on sentry-guarded facilities to conduct reconnaissance; for ground systems to work collaboratively with unmanned aircraft to help protect military bases and outposts; and for heavy-lifting equipment to become semiautonomous so that humans can remotely clean up contaminated areas following disasters.

Most autonomous systems navigate by detecting the world using cameras, radar and other sensors. To get to a door, for example, robots typically chart paths that take them as far away from obstacles as possible. But to maneuver covertly, the vehicles must traverse closer to obstacles and roll along a wall or a tree line in order to reduce their visibility to potential threats, said Brian Satterfield, lead member of the engineering staff for the covert robotics research program at Lockheed Martin Advanced Technology Laboratories.

Academic researchers previously developed algorithms for covert movement in autonomous vehicles. But if the robot were to be spotted by someone as it employed those processes, it would have no capability to move and hide from the potential threat he said. The Lockheed Martin engineers developed a method for the robot to quickly ascertain good hiding locations with options for escaping should detection occur.

"Without the escapability algorithm, you wind up picking locations like a phone booth," Satterfield said. "Sentries would come walking in and would be able to see you for a long time. Whereas with escapability, you can run and hide and the sentry sees you for a short amount of time," if at all.

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Detecting sentries and other potential threats required the development of a "time delay of arrival" algorithm to pinpoint the source of a sound, such as approaching footsteps. On board a small, wheeled vehicle made by Active Media Robotics, Lockheed engineers placed a microphone array on four masts. Any noise would hit...