  In this paper, we propose a drone-based wildfire monitoring system for remote
and hard-to-reach areas. This system utilizes autonomous unmanned aerial
vehicles (UAVs) with the main advantage of providing on-demand monitoring
service faster than the current approaches of using satellite images, manned
aircraft and remotely controlled drones. Furthermore, using autonomous drones
facilitates minimizing human intervention in risky wildfire zones. In
particular, to develop a fully autonomous system, we propose a distributed
leader-follower coalition formation model to cluster a set of drones into
multiple coalitions that collectively cover the designated monitoring field.
The coalition leader is a drone %with longer communication range that employs
observer drones potentially with different sensing and imaging %actuation
capabilities to hover in circular paths and collect imagery information from
the impacted areas. The objectives of the proposed system include i) to cover
the entire fire zone with a minimum number of drones, and ii) to minimize the
energy consumption and latency of the available drones to fly to the fire zone.
Simulation results confirm that the performance of the proposed system --
without the need for inter-coalition communications -- approaches that of a
centrally-optimized system.
