Keeping the Ball from CMUnited-99 (2001)
David McAllester and Peter Stone
This paper presents preliminary results achieved during our development of a team for simulated robotic soccer in the RoboCup soccer server. In preperation for the 2000 simulation competition we constructed a team that plays a simplified ``keepaway'' game. Playing keepaway against the 1999 RoboCup champion CMUnited-99 team, our keepaway program holds the ball for an average of 25 seconds with an average distance of 24 meters from the opponents end of the field. CMUnited-99 playing against itself holds the ball for an average of only 6 seconds. Here we describe the design of the keepaway team and the results achieved on the keepaway task. The principal technique used is the vector sum of force-fields for governing player motion when they are not in possession of the ball. The control methods developed for the keepaway task were eventually incorporated into a team that outscores CMUnited-99 at a rate of eight goals for every opponent goal. This team took third place in the robocup 2000 simulator competition.
In RoboCup-2000: Robot Soccer World Cup IV, Peter Stone and Tucker Balch and Gerhard Kraetzschmar (Eds.), Vol. 2019, pp. 333-338, Berlin 2001. Springer Verlag.

Peter Stone Faculty pstone [at] cs utexas edu