We introduce and study a new search-type problem with (n+1)-robots on a disk. The searchers (robots) all start from the center of the disk, have unit speed, and can communicate wirelessly. The goal is for a distinguished robot (the queen) to reach and evacuate from an exit that is hidden on the perimeter of the disk in as little time as possible. The remaining n robots (servants) are there to facilitate the queen’s objective and are not required to reach the hidden exit. We provide upper and lower bounds for the time required to evacuate the queen. Namely, we propose an algorithm specifying the trajectories of the robots which guarantees evacuation of the queen in time always better than (formula presented) for n ≥ 4 servants. We also demonstrate that for n ≥ 4 servants the queen cannot be evacuated in time less than (formula presented).

Disk, Evacuation, Exit, Group search, Mobile robots, Priority, Queen, Servants, Wireless communication
Lecture Notes in Computer Science
School of Computer Science

Czyzowicz, J. (Jurek), Georgiou, K. (Konstantinos), Killick, R. (Ryan), Kranakis, E, Krizanc, D. (Danny), Narayanan, L. (Lata), … Shende, S. (Sunil). (2018). Priority evacuation from a disk using mobile robots. In Lecture Notes in Computer Science. doi:10.1007/978-3-030-01325-7_32