Mechanical Engineering Graduate Student Brooks Reed (MIT WHOI, Woods Hole Oceanographic Institute) is building fast, cooperating robots that can explore the ocean’s dynamic features using the Charles River as a testbed. If you take a stroll past the MIT Sailing Pavilion on Memorial Drive, you may see, among the usual glut of sailboats on the Charles River, two red child-sized kayaks riding the waves. Instead of the 80-pound human they are each designed to hold, the kayaks carry an array of electronics and a pull-along a string of plastic flags that flutter in the wind. These baby kayaks are a key element of robotic control systems research led by Franz Hover, Associate Professor of Mechanical Engineering at MIT, graduate student Brooks Reed, and their colleagues – a project which was just accepted into the International Symposium on Robotics Research (ISRR).
Reed is monitoring real-time data streaming in from the GPS mounted on the kayaks. Each of the kayaks tow an acoustic WHOI Micro-Modem at a depth of about 1.5 meters. Icarus, the target vehicle, sends out a pulse of sound, called a “ranging ping.” Silvana and Nostromo receive it and calculate the the ping’s travel time. By dividing that number by the speed of sound in water, they can compute their own distances from Icarus. Then, they coordinate. Each swap their own location measurements and control actions by sending data packets to each other using the modems. Therefore, the pursuers know where to go next. The pair achieve their joint goal of maintaining a tight triangular formation relative to the position of Icarus, tracking their target even as it turns in unpredictable loops.