  Autonomous exploration allows mobile robots to navigate in initially unknown
territories in order to build complete representations of the environments. In
many real-life applications, environments often contain dynamic obstacles which
can compromise the exploration process by temporarily blocking passages, narrow
paths, exits or entrances to other areas yet to be explored. In this work, we
formulate a novel exploration strategy capable of explicitly handling dynamic
obstacles, thus leading to complete and reliable exploration outcomes in
populated environments. We introduce the concept of dynamic frontiers to
represent unknown regions at the boundaries with dynamic obstacles together
with a cost function which allows the robot to make informed decisions about
when to revisit such frontiers. We evaluate the proposed strategy in
challenging simulated environments and show that it outperforms a
state-of-the-art baseline in these populated scenarios.
