Ball Interception Behaviour in Robotic Soccer Jo˜ao Cunha, Nuno Lau, and Jo˜ ao Rodrigues Universidade de Aveiro Abstract. In robotic soccer the ball is the most crucial factor of the game. It is therefore extremely important for a robot to retrieve it as soon as possible. Thus ball interception is a key behaviour in robotic soccer. However, currently most MSL teams move to the ball position without considering the ball velocity. This often results in inefficient paths de- scribed by the robot. This paper presents the CAMBADA solution for a ball interception behaviour based on a uniformly accelerated robot model, where not only the ball velocity is taken into account but also the robot current velocity as well as the robot acceleration, maximum velocity and sensor-action delays are considered. The described work was introduced in the Portuguese robotics open Rob´otica2009 and RoboCup 2009 and improved the team performance contributing to the first and third places, respectively. 1 Introduction Robotic soccer, much like human soccer, revolves around a key aspect of the game: the ball. To win, a team must make an efficient use of it, either by passing it to a team-mate, by dribbling it towards the goal, or by shooting it on goal in order to score. However even the most technically evolved robot cannot perform such moves if it doesn’t regain possession of the ball as fast as possible. In order to obtain the ball, depending on the situation, a robot must catch a loose ball, receive a pass or tackle it from an opponent. However, most MSL teams, currently move to the ball position, without considering its velocity. Given the increasingly dynamic aspect of the game over recent years, the ball is constantly moving therefore this method doesn’t provide the most efficient path to regain ball possession. This paper describes the developed solution implemented within the framework of the CAMBADA project at the University of Aveiro. The CAMBADA is the University of Aveiro robotic soccer team competing in the RoboCup [4] Middle Size League. The project started in 2003 by researchers of IEETA 1 ATRI 2 research group and students from DETI 3 of the University of Aveiro. The multidisciplinary project includes diverse research areas such as 1 Instituto de Engenharia Electr´ onica e Telem´ atica de Aveiro - Aveiro’s Institute of Electronic and Telematic Engineering. 2 Actividade Transversal em Rob´ otica Inteligente - Transverse Activity on Intelligent Robotics. 3 Departamento de Electr´onica, Telecomunica¸c˜oes e Inform´ atica - Electronics, Teleco- munications and Informatics Department. T. R¨ ofer et al. (Eds.): RoboCup 2011, LNCS 7416, pp. 114–125, 2012. c  Springer-Verlag Berlin Heidelberg 2012