Decentralized robotic assembly with physical ordering and timing constraints

Our prior work presented a system for decentralized robotic assembly[1]: given a team of robots, a cache of components, and a desired structure specified as a blueprint, the algorithm computes a sequence of part deliveries and assembly steps to achieve the desired structure, while considering physical dependencies and reachability constraints for the goal structure. In this paper we introduce a new algorithm that extends our prior result to incorporate the duration of each assembly operation. We also extend the algorithm to be adaptive to the availability of parts. When a part is not available, the assembly sequence is recomputed. The algorithms are provably convergent and their execution does not depend on the size of the robot team. We implement the algorithms using a team of four youBot robots that can (1) locate and identify parts; (2) use communication to achieve coordinated hand-off of parts; and (3) create complex log-cabin style structures.