Development of BEST nano-robot soccer team

In this paper, we describe the development of our BEST nano-robot soccer team composed of 5 robots, a vision system, and communication modules. Each nano-robot is designed with an all-in-one type microcontroller and two DC motors fixed in parallel due to its small size, 4(cm)/spl times/4(cm)/spl times/4.5(cm). A vision system capable of 30 recognitions/sec provides each robot's position feedback via RF communication. A three level hierarchical software control scheme is adopted: role allocation, target generation, and visual servoing. Dynamic role allocation is done in the highest layer (the role allocation layer) regarding the context and role importance. In the target generation layer, target positions of robots are generated based on 6 roles, 2-2-1 formation, and libero system. In the visual servoing layer, path planning is achieved using a newly proposed line-circle algorithm with linear and circular paths as our basic strategy. Normally, 2-2-1 formation is adopted. When the both attackers are blocked, one of defenders is assigned to continue the attack as libero (temporary 3-1-1 formation).