Middle-Size League

Introduction

The Middle-Size League (MSL) is concerned with wheeled robot teams playing soccer. The league is well-known for its fast moving robots and maneuvers, making the crowd cheer every year in the MSL finals.

The challenges include high velocity control, self-localization, navigation, and perception on resource-limited systems, and multi-robot coordination under real-time constraints in a highly dynamic and adversarial environment.

The AllemaniACs team is no longer actively participating in the Middle-Size League.

Robot Platforms

The MSL has in its first decade was driven by several generations of hardware and software improvements to enable ever faster game-play. The development of the first platform started in 2001 (left image), with the first world cup participation at RoboCup 2003 (Padua, Italy). Intended also to serve as a service robot platform it was equipped with a powerful differential drive allowing robots to reach speeds of $3\,\mathrm{m}/\mathrm{s}$ and transporting large weights of $80\,\mathrm{kg}$. The first generation featured an electro-mechanical kicking device. The second generation, extending the existing platform starting construction in 2004 (middle image), was equipped with a pneumatic kicking device and allowed to do high kicks. It was also equipped with a omni-cam, a camera facing upwards towards a spherical mirror (a coated light bulb in this prototype) to get a full round view in every image. However, all other participants in the league had moved on to holonomic platforms enabling moves in all directions without turning. These were much faster to reach and align at a ball. In 2006, we participated for the last time with this platform. As there were many more registrations than space, we participated in a joint team with Mostly Harmless from Technical University Graz. Immediately following, a new platform was designed (right image), featuring a holonomic drive system and pneumatic kicking with a combination of a cylinder and two pneumatic artificial muscles, enabling angled and high kicks. The platform used a combination of a 3D stereo camera and a omni-directional camera. The platform was tested for the first time at RoboCup 2007 (Atlanta, GA, USA). We have participated in several German Open competitions until 2010.

Research

Research was focused on the development of a deliberative component named ReadyLog supporting goal-directed coordinated acting of multi-robot system with real-time constraints. As a further development of the logic-based robot programming language Golog we integrated features like continuous change, probabilistic projections, MDP planning, and MDP options into our GOLOG dialect. Equipped with a run-time system interleaving planning and plan execution and explicit agent programming is possible. Besides the deliberative part, we believe that sometimes reactive behaviors must override deliberation, so called opportunistic behaviors, when the performing an action seems obvious: in front of the free opponent goal the appropriate action is a goal kick. This raises of course the question of how to choose between plans (deliberative) and opportunistic behaviors (reactive). Another interesting research area is the area of modeling the world qualitatively in order to speed up planning, making the computed plans more robust and flexible to changes in the real world. Moreover, we are interested in integrating opponent behavior into planning and learn appropriate models for this during the play.

The project was funded as part of the Priority Program 1125 of the German National Science Foundation (DFG).

Selected Publications

Team

The AllemaniACs Mid-Size team was led by Alexander Ferrein (2002-2006) and Daniel Beck (2007-2010). The team was supervised by Prof. G. Lakemeyer, PhD.


Other team members included: Florian Bley, Frank Dylla, Benjamin von Eicken, Christian Fritz, Carsten Gester, Claudia Gönner, Martin Heracles, Lutz Herrmanns, Florian Hess, Stefan Jacobs, Mirko Kohns, Volker Krause, Martin Liebenberg, Christoph Mies, Tim Niemueller, Martin Rous, Stefan Schiffer, Volker Schmirgel, Christoph Schwering, Nils Springob, Andreas Strack, Philipp Vorst, Jost Wunderlich, Hu Yuxiao.

Awards

Awards won by the AllemaniACs team related to the RoboCup Middle-Size Soccer League.