RoboCup Learning By Observation - Upcoming Journal Paper

This page is a complement to the, as yet unpublished, journal article about learning by observing RoboCup soccer agents using a case-based reasoning system. This page aims at providing multimedia examples of the experiments to help the reader better appriciate the performance of the system. Also, this page provides more complete experimental results and the data which was used in those experiments.
Teams to Observe - Videos:
  • Krislet - We show two teams of Krislet agents playing against each other in a 1 on 1, 5 on 5 and 11 on 11 game. The reason we show all of these is that there are slight differences that become visible as the number of players increase. In the 1 on 1 game, we can clearly see the Krislet behaviour. Each player turns until they can see the ball, run toward the ball and kick the ball toward the opponent's goal net. They demonstrate this behaviour quite clearly, because there is only one other agent to compete against. The 5 on 5 is quite similar, but if you watch closely you will see players occasionally losing track of the ball when other players are swarming around it. This becomes significantly more common in the 11 vs 11 game, and you can see the players lose track of the ball quite often. This is because with so many other player, they do not see the ball because there are other players in the way. Since the Krislet agents do not use past information to reason (for example, that the previous cycle the ball was directly infront of them) they think the ball has moved out of their field of vision so they turn to look for it. Although the 11 vs 11 game is more like a real soccer game, the behaviour of the players appears different compared to when there are only 1 or 5 players per team.
  • Sprinter - This video is of 11 Sprinter players against 11 Krislet players (also 3 vs 3, 1 vs 1 and a single Sprinter agent). The Sprinter players do not pay any attention to the game and spend the entire game trying to run from one end of the field to the other. Unfortunately for the Sprinter players they are often interrupted when Krislet scores and have to start their run again from their own end of the field.
  • Observer - The video shows three Observer agents against three Krislet agents. The Krislet agents were added just so there is some movement of the field, because if there are just Observer agents they quickly get to a state of equilibrium. You can see that the Observer agents always turn so they can see at least two other players. If the furthest player they can see is relatively far away, they run toward it. If the furthest player is relitively close, they back up. Otherwise, they just kick (that is when they blink). They do not kick for any reason, just something to do while they look at the other players. You can see from the video that the reason they are called Observer agents is because they like to watch other players, but move away when they get too close.
  • Passer - If you watch the video with two Passer agents, you will notice that in general they are in different states at different times. One agent, if the passing state, will chase the ball, kick it to the other and enter the receiving state. When the ball gets close enough to the other agent, it trasitions out of the receiver state and into the passer state. You will notice occasionally, when they are very close to each other, that they are both in the passer state. This is because they think, since the ball is close to them, that it was passed to them. As you can see in the video they eventually find there way out of this situation. Another thing you might notice is that they are are both occasionally in the receiver state. This usually happens when a pass is not completed well, but they get out of this situation because they have a timeout that occurs if they are in the receiver state too long.
  • CMUnited - When watching the CMUnited team play against Krislet in an 11 vs 11 match, there is a clear and significant difference between CMUnited and the previous teams we have seen. When you watch the players, you can see they are clearly aware of their teammates (and opponents) and anticipate where the other players will move to when making passes or defending. This is in contrast to Krislet, who is in an environment with other players but never tries to directly interact with them (for example, by passing the ball). As well, we can see multiple states of behaviour like when CMUnited players switch between an offensive and defensive mode.
Teams to Observe - Agents:
  • Krislet - the Java source code of the Krislet agent used in the experiments and videos. Each instance of this program represents a single player, so the code would need to be run 11 times for a team of 11 players.
  • Sprinter - the Java source code, based on the source code for Krislet.
  • Observer - the Java source code, based on the source code for Krislet.
  • Passer - the Java source code, based on the source code for Krislet.
  • CMUnited - the linux binaries of the team. This may not work on never versions of linux, so be warned.
Teams to Observer - Log Files:
This page will be updated as the journal publication is written. If you would like to read the article in its current version (possibly incomplete) please contact Michael Floyd.