OXSY 2015 Team Description

Sebastian Marian, Dorin Luca, Bogdan Sarac, Ovidiu Cotarlea

OXygen-SYstems laboratory, Str. Constantin Noica, Bl.5, Sc.C, Ap.36, C.P. 550169, Sibiu, ROMANIA

http://oxsy.ro

Abstract Oxsy team was founded in July 2002 for a graduation project of one student, Sebastian Marian, in the field of Multi-Agent Systems, at the Department of Computer Science of Lucian Blaga University (Sibiu - Romania). After graduation he continued the work on this project and so was born Oxsy team. As we started from scratch, our ideas, concepts and beliefs, was implemented year by year and today, we are happy to see that we are on the right way, as our team was growing in these years, more than we expected from the beginning. If we'll qualify to the competition, this year we'll reach at the 13th consecutive participation, in RoboCup Soccer Simulation League.

Introduction

In July 2003 at RoboCup competition, which was held in Padua - Italy, we won the first round and for us it was a good surprise for first year of participation. Then, in the next year, we participated in Lisboa - Portugal for the second time, and again we obtained a good result (the 11th place). In 2005 in Osaka – Japan, we participated for the third time and finally we entered in the first 8 teams of soccer simulation league, as we won (the 8th place). In 2006 the competition was held in Bremen – Germany and we won (the 7th place). In 2007 we went to Atlanta – Georgia (U.S.A), where we obtained (the 5th place), the same result which we achieved in 2008 in Suzhou – China. Finally, in 2009 in Graz, we entered in the first 3 teams in the soccer simulation league, as we won (the 3rd place), the same result which we achieved in 2010 in Singapore. In 2011 we came back from Istanbul - Turkey with 4th place. In 2012 we were in Mexico City, where we had a bad experience as we made some major changes in our defensive system, and also many others overall our team strategy, changes which was not very well balanced at that time, with all others characteristics of our team, as we didn't qualified for finals, from the second round groups. In 2013 we came back in top, as we won the 6th place, in Eindhoven – Netherlands. Last year the competition was held in Joao Pessoa – Brazil, and we entered on the stage for the third time in our participation history, as we won again the 3rd place. This year the competition will be held in Hefei - China. As we already have a very good experience in 2D Soccer Simulation league, we hope that our new ideas and improvements will be reflected in the competition where we will also test other tactical elements developed.

Pressing in the attacking zone

In order to get the best results and, in any case, to make our team as strong as possible, we must take care of every little detail, even those things that may look marginal. In fact, when the technical ability of two teams is more or less on the same level, it is the details that often make the differences.

This year, we continued to prepare our team defense phase with careful attention of this tactical action named pressing. In fact, pressing is a collective tactical action, carried out by more than one player, and performed in situations of non-possession. We should make a distinction between putting a player under pressure and pressing a player. Putting a player under pressure is an individual action, carried out in order to take away playing space and time from the opponent in possession. Instead, pressing means that a number of players are cooperating simultaneously so as to reach a common aim. The purpose of pressing is to close up the spaces and playing time for the team that is in possession, making it difficult for them to develop their attacking moves and easier for us to regain the ball. We also classified the types of pressing, depending to the part of the field where these collective actions are applied in the most systematic way (Fig. 1.):

• ultra-offensive pressing;
• offensive pressing;
• defensive pressing.

Future work

For the next future, we'll involve our coach in many others issues, where the team really needs his help. Even if the free form messages, are limited by count and periods of sending, the power of the coach remain very important, as he can receive free noises information. In this way, he can analyze many important aspects of the games and if he'll deliberates based on these information, he can give valuable advices to his own team.

We must accept that right now, many teams involved in this competition, adapt theirs strategy before the game is started instead of while it running. A team will be more powerful, when it can adapt correctly his strategy depending of the opponent behaviors and not by the opponent's name, and also during the game and not only before it starts. In this way, we tried to adapt our team to some unexpected situations, which are generated by different playing style of our opponents. In the real soccer, the role of the coach during the game is very important, and this is not only because of the players that he's changing, but because of many good advices that he gives to his team. In the same way we must think more and more to the power of the coach and how we can use it in our simulator.

References

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2. Jinyi Yao, Jiang Chen, Zengqi Sun. An application in RoboCup combining Q-learning with Adversarial Planning. Available in http://robocup.lits.tsinghua.edu.cn/download/document/tsinghuaeolus_kick.zip.
3. M. Riedmiller and Artur Merke, " Using machine learning techniques in complex multiagent domains," In I. Stamatescu, W. Menzel, M. Richter and U. Ratsch, editors, Perspectiveson Adaptivity and Learning, LNCS, Springer, 2002.
4. Itsuki Noda et al, Soccer Server Manual, RoboCupFederation. http://www.robocup.org.
5. Y. Jinyi, C. Jiang, and S. Zengqi. An application in RoboCup combining Q-learning with Adversarial Planning. In the 4th World Congress on Intelligent Control and Automation (WCICA'02), Shanghai, China, June 2002.
6. Peter Stone and David McAllester. An Architecture for Action Selection in Robotic Soccer. In Proceedings of the Fifth International Conference on Autonomous Agents, pages Pages: 316–323, 2001.
7. Takashi Suzuki. Team YowAI Description. RoboCup 99: Robot Soccer World Cup III, 2000.
8. Pressing, by Lucchesi Massimo, editing Bryan R. Beaver, printed by DATA REPRODUC-TION Auburn, Michigan.