Dynamic coordination between robots: self-organized timing selection in a juggling-like ball-passing task

This paper describes the hierarchical architecture for a rhythmic coordination between robots, which suits juggling-like tasks involving sensory-motor coordination. The authors\´ approach, which is interpreted as a "bidirectional weak coupling" to the environment, does not require either the environmental model or continuously monitoring the environment but can adapt the robots to a change in the environment, owing to the interaction between the robots and the environment at the ball contact. The proposed architecture contains two passive-control mechanisms, the "open-loop stable mechanism" and the "entrainment mechanism", that lead to the emergence of self-organized temporal structure for rhythmic movement. This dynamic pattern in the whole system realizes the stable coordinated motion between robots. The authors demonstrate two motion patterns between two robots passing two balls, and confirm the effectiveness of the approach