Nancy Baker Cahill created FREE, an augmented reality artwork that appears above Alcatraz Island and can be seen from the San Francisco waterfront. The island sits more than a mile offshore across open water. There was nowhere to put a marker and nothing nearby for a phone to scan, so the artwork had to find the island by itself.
Markerless Tracking
Problem
Most AR experiences anchor content to a printed marker or to surfaces the phone can scan close by. Alcatraz is about 1.25 miles away across the bay, far beyond the range of standard AR tracking, and markers weren't an option.
Solution
Building on the computer vision tech we developed for Body Politic, we trained a custom model to recognize Alcatraz from the shoreline. From where the island appears in the camera view, our software works out its distance and direction and places the artwork over it. The phone's own AR tracking then takes over and keeps it steady as the viewer moves.
Result
Visitors just point their phones at the island and FREE appears over it, locked in place. There are no markers, no setup and no calibration.