Stochastic strategies for patrolling a terrain with a synchronized multi-robot system

•A team of UAVs to efficiently patrol a terrain is considered.•Each robot flies around an assigned area and periodically shares information with the neighbors.•In case of fail, a remaining robot pass to the neighboring area to ensure robustness of the system.•Random strategies are studied both theoretically and experimentally.•Simulations show that theoretical results are in good agreement with the experiments.