  This work proposes an autonomous multi-robot exploration pipeline that
coordinates the behaviors of robots in an indoor environment composed of
multiple rooms. Contrary to simple frontier-based exploration approaches, we
aim to enable robots to methodically explore and observe an unknown set of
rooms in a structured building, keeping track of which rooms are already
explored and sharing this information among robots to coordinate their
behaviors in a distributed manner. To this end, we propose (1) a geometric cue
extraction method that processes 3D point cloud data and detects the locations
of potential cues such as doors and rooms, (2) a circular decomposition for
free spaces used for target assignment. Using these two components, our
pipeline effectively assigns tasks among robots, and enables a methodical
exploration of rooms. We evaluate the performance of our pipeline using a team
of up to 3 aerial robots, and show that our method outperforms the baseline by
33.4% in simulation and 26.4% in real-world experiments.
