Finally, it combines these into a 3-D rendering of the space. The observer robot carries a second camera that is focused on the ceiling. This helps it keep track of its position by recognizing block patterns that the researchers have attached to the ceiling in a grid pattern. The observer robot uses this to identify it. In an associated project with Professor Ruzena Bajcsy's group at the University of Pennsylvania, Latombe and his students are working on a technique that will allow the robot to identify and track unmarked robots and people.
Human operators have a choice of two views on their computer screens.
In one, they can see the view from the AO's horizontal camera. But when the robot is zipping hither and yon and panning quickly back and forth, this viewpoint can leave people pretty woozy, Gonzalez-Banos says. So, in most cases, the operators choose the 3-D view that shows the position of the observer and target robots within the representation of the space that the AO initially created. So far, the researchers have been experimenting with a single observer and a single target. The robots, which were built by Nomadic Technologies of Mountain View, Calif., are about 4 feet tall and resemble an upright tank vacuum cleaner without the hose.