A distributed protocol for safe real-time planning of communicating vehicles with second-order dynamics
Kostas E. Bekris, Konstantinos I. Tsianos, Lydia E. Kavraki · 2007
Abstract—This work deals with the problem of planning in real-time, collision-free motions for multiple communicating ve-hicles that operate in the same, partially-observable environment. A challenging aspect of this problem is how to utilize communi-cation so that vehicles do not reach states from which collisions cannot be avoided due to second-order motion constraints. This paper provides a distributed communication protocol for real-time planning that guarantees collision avoidance with obstacles and between vehicles. It can also allow the retainment of a com-munication network when the vehicles operate as a networked team. The algorithm is a novel integration of sampling-based motion planners with message-passing protocols for distributed constraint optimization. Each vehicle uses the motion planner to generate candidate feasible trajectories and the message-passing protocol for selecting a safe and compatible trajectory. The existence of such trajectories is guaranteed by the overall approach. Experiments on a distributed simulator built on a clus-ter of processors confirm the safety properties of the approach in applications such as coordinated exploration. Furthermore, the distributed protocol has better scalability properties when compared against typical priority-based schemes. I.