Initiated by the Japanese computer scientist Hiroaki Kitano, RoboCup this year will draw 440 teams from 38 countries to compete for the prestigious title of robotic soccer world champion. This is the first time Germany has hosted the event, which runs from June 14 to 18.
"Soccer is used as a standardized engineering problem that allows a comparison of different research areas," said Ubbo Visser from the Technologie-Zentrum fùr Informatik Bremen, one of the organizers of the event. "During the course of the game, the robots have to be able to move completely autonomously, which means without human interaction or remote control."
In the first years of the RoboCup, scientists considered alternatives to soccer for their world cup, including games like baseball or volleyball. "But these games are less dynamic than soccer," said Kitano. "For instance, in volleyball, the players are separated by a net, and also in the other games there is a very clear distinction between attackers and defenders." In the end, he said, "soccer turned out to be the best alternative. It is very dynamic and requires a high degree of teamwork."
The teams compete in a number of leagues, according to the abilities of players made of silicon, software and steel. While the Small Size League is considered the fastest, the robots in the Simulation League think more deeply and those in the Humanoid League make use of more complex sensor networks. Other leagues are the Middle Size League, the Four-Legged League, the Junior League and the Rescue League.
One type of soccer-playing robot can be found in the B-Smart team of Bremen University. In the class in which its robot is competing, the size must not exceed a footprint of 180 square centimeters and it cannot be taller than 15 cm (1/2 foot). B-Smart's robot runs on four wheels with a specific mechanism so that it can change direction without turning around. Its kicking mechanism, powered by a solenoid and a capacitor, accelerates the ball to a speed of 10 meters per second. Within 130 milliseconds, the robot processes the image of two cameras in order to identify its position on the playing field and the position of the other team members, as well as the adversary.
Robot soccer is a discipline of artificial intelligence, but its requirements go far beyond software. The machines show off the latest developments in sensor technology, processors, actuators and embedded-system technology. The long-term objective is to form a team of autonomous humanoid robots that can win against a human team—and not just any human team, but the World Cup winners themselves. This certainly could prove to be a challenge, but there's time for the robots to prepare: RoboCup's goal is for the decisive game to take place in 2050.
