Robotic soccer can be played either with real robots or in a simulator. Although more costly and time consuming to develop, a number of groups have developed real robotic systems. The first robotic soccer system was the Dynamo system . Sahota et al. built a 1 vs. 1 version of the game. Asada et al. have used vision-based RL with their soccer playing robots . Veloso et al. discuss some of the robotic issues involved in building robotic soccer players [3, 89].
Some robotic issues can only be studied in the real-world instantiation, but there are also many issues that can be studied in simulation. A particularly good simulator for this purpose is the ``soccerserver'' developed by Noda  and pictured in Figure 12.
Figure 12: The soccerserver system
This simulator is realistic in many ways: the players' vision is limited; the players can communicate by posting to a blackboard that is visible to all players; all players are controlled by separate processes; each player has 10 teammates and 11 opponents; each player has limited stamina; actions and sensors are noisy; and play occurs in real time. The simulator provides a domain and supports users who wish to build their own agents. Furthermore, teams of agents can be evaluated by playing against each other, or perhaps against standard teams. The simulator was successfully used for a competition among twenty-nine teams from around the world in 1997 . Thus robotic soccer satisfies Decker's criteria for DAI testbeds .