Search for Smart Evaders With Swarms of Sweeping Agents

Suppose in a given planar region, there are smart mobile evaders and we want to detect them using sweeping agents. We assume that the agents have line sensors of equal length. We propose procedures for designing cooperative sweeping processes that ensure successful completion of the task, thereby deriving conditions on the sweeping velocity of the agents and their paths. Successful completion of the task means that evaders with a known limit on their velocity cannot escape detection by the sweeping agents. A simpler task for the sweeping swarm is the confinement of the evaders to their initial domain. The feasibility of completing these tasks depends on geometric and dynamic constraints that impose a lower bound on the velocity the sweeping agent must have. This critical velocity is derived to ensure the achievement of the confinement task. Increasing the velocity above the lower bound enables the agents to complete the search task as well. We present results on the total search time for two types of novel pincer-movement search processes, circular and spiral, for any even number of sweeping agents. The proposed spiral process allows detection of all evaders while sweeping at velocities that approach the theoretical lower bound.