Testing Artificial Intelligence on German Soccer Fields
May 16, 2006
Even without shin pads, a bruise would be more likely than a broken leg if "Robotinho" were to slide tackle a person. In fact, the move would probably do more damage to the lightweight metal frame and electronics that fill the five-kilo, 60-cm (11-pound, 23-inch) robot than the opposing player -- if it was capable of sliding.
"Moving forward on two legs is not so reliable," said Sven Behnke of some of the humanoid robots he has created at the Albert-Ludwigs University in Freiburg, home to "Robotinho" as well as "Sepp" and "Jupp," two other robots that won an April Robocup event in Holland. "They often end up pushing each other over when they get close to each other and fight for the ball."
How far Behnke and his team have come with their robots will be put to the test next month in Bremen, where robots on some 350 teams from 40 countries play in four size-based leagues and one computer-based simulation league at the 10th Robot World Cup, an international initiative designed to research and development of robotics and artificial intelligence.
No remote controls allowed
Just like the players on soccer's more traditional pitches, the robots make their own decisions when it comes to shooting or passing. While a human defender's umpteenth clearance into the upper-deck may look robotic to fans hoping for a goal, getting robots to decide they need more time to defend is just one of the problems facing programmers.
Each robot has to recognize objects on the field, know where it is in relation to other players, dribble the ball and follow a set of simplified, FIFA-based rules independent of outside influence. Ideally, they should also show some team spirit by cooperating with each other.
"Everything humans can do naturally has to be programmed in the robots," Mainz University's Peter Dauscher said of the machines, which can cost upwards of 3,000 euros ($3,851). "They need to be able to analyze the situation and decide what they should do."
Robocup organizers -- the sport has two international robot soccer federations, similar to world soccer governing body FIFA, as well as numerous national clubs -- have set an ambitious goal of fielding a team capable of beating a human World Cup team by 2050.
"It's a very ambitious goal," Dauscher said. "Right now the robots have a hard time playing against three-year-olds."
Conferences drive scientific development
To help speed up development, the competitions are accompanied by scientific conferences where researchers are able to share information and detail how their droids process the thousands of decisions involved in a soccer game.
A detailed set of rules exists to help the robots play autonomously. The white sidelines and the orange ball look familiar, but different colored goals -- one blue and one yellow -- are intended purely to help the robots calculate where they are on the field.
"What is taking place in the humanoid league does not really have very much in common with a soccer game," said Dauscher, describing robot soccer's lack of end-to-end action.
Despite the slower pace and fewer players on the field, two-on-two matches started in the humanoid league last year, and fans are still willing to watch robots battle to become Robocup champions.
There were 180,000 at the 2005 Osaka Robocup, and Hubert Borgmann of Messe Bremen, one of the 2006 Robocup organizers, said he expects about 30,000 visitors in addition to the 2,500 researchers at the June 14 to June 18 event in the northern German city. He said the attendance difference is due to a greater acceptance of robots in Japan.
Probing on a level playing field, literally
The soccer and robotics fans who do attend shouldn't expect to see robots dancing in celebration with the corner flag after scoring a goal -- that's far from the researchers' main goal. Instead the competition is used to put the robots in a standardized situation, which keeps different research groups from using different criteria to measure their performance while testing the robot's ability to perceive its surroundings.
"The soccer tournament is a good test area for many aspects of what is being developed," Dauscher said, adding that advanced mechanics, photo recognition and artificial intelligence are among the many skills researchers are still trying to teach robots. "In the game the robots see the ball, their opponents and the goalposts, in a daily situation it could be the cat, a chair and the oven."
The scientists admit their research isn't far enough along that robots are going to start taking over household duties or the soccer field soon, however, they also agreed robotics and artificial intelligence continues to develop quickly, making it extremely difficult to predict how the robots could be used in the future.
"Computers 50 years ago were dinosaurs compared to today's pocket computers and mobile phones," Behnke said. "The technology can develop dramatically, so it's difficult to predict what is going to happen."