Robust Supporting Role in Coordinated Two-Robot Soccer Attack

In spite of the great success of the fully autonomous distributed AIBO robot soccer league, a standing challenge is the creation of an effective planned, rather than emergent, coordinated two-robot attack, where one robot is the main attacker and goes to the ball and the other robot "supports the attack." While the main attacker has its navigation conceptually driven by following the ball and aiming at scoring, the supporter objectives are not as clear. In this work, we investigate this distributed, limited perception, two-robot soccer attack with emphasis on the overlooked supporting robot role. We contribute a region-based positioning of the supporting robot for a possible pass or for the recovery of a lost ball. The algorithm includes a safe path navigation that does not endanger the possible scoring of the teammate attacker by crossing in between it and the goal. We then further present how the supporter enables pass evaluation, under the concept that it is in a better position to visually assess a pass than the attacker, which is focused on the ball and surrounded by the opponent defense. We show extensive statistically significant lab experiments, using our AIBO robots, which show the effectiveness of the positioning algorithm compared both to a previous supporter algorithm and to a single attacker. Additional experimental results provide solid evidence of the effectiveness of our passing evaluation algorithm. The algorithms are ready to incorporate in different RoboCup standard platform robot teams.