Helping robots collaborate to get the job done

Consider a search-and-rescue mission to find a hiker lost in the woods. Rescuers might want to deploy a squad of wheeled robots to roam the forest, perhaps with the aid of drones scouring the scene from above. The benefits of a robot team are clear. But orchestrating that team is no simple matter. How to ensure the robots aren't duplicating each other's efforts or wasting energy on a convoluted search trajectory?