Robot of the Week: the Friendliest Little Autonomous Explorer

A low-tech alternative to GPS

Your mother told you never to speak to strangers, but what if the stranger was a robot on wheels, who was lost and needed your help? Thirty-eight people in this very predicament chose to speak to the waylaid robot, whose task was to cross a busy city without a map or GPS. All it could do was ask directions.

Munich was the city it was crossing, and Autonomous City Explorer (ACE) was the robot, the brainchild of Martin Buss and his colleagues at the Technical University of Munich. Buss’ team released the mobile robot outside the university and instructed it to find its way to the Marienplatz in the center of Munich, almost a mile away.

ACE was equipped with a camera for eyes, a touchscreen for a face, an animated touchscreen mouth with a synchronized speaker for a voice, and various sensors, which allowed it to recognize humans by their motion and upright posture, turn its crude face towards it and ask for help. If the person touched the screen indicating he or she was willing to help, ACE asked them to point in the correct direction and then used posture recognition software to analyze the response. ACE politely gave thanks and rolled in that direction.

While having robots traverse and map unknown terrain is not a new phenomenon, including humans in the process is — a real bonus when the robot is navigating through environments that may be in flux. Teaching robots to communicate in human terms is essential for integrating them into the real world.

ACE took nearly five hours to traverse the mile — this isn’t the robot you want to be calling when your house is on fire. Its progress wasn’t helped by curious passersby who interacted with it as it entered the denser part of the city.

And while most of the 38 strangers ACE encountered were kind, it did cross paths with someone who sent it in the wrong direction. The researchers have yet to prankster-proof their robot.