Probabilistic strategies for sensor-based exploration

We discuss a strategy for sensor-based exploration of unknown environments by a mobile robot. The strategy, called SRT-Ball, is an instance of a general paradigm based on the randomized generation of a sensor-based random tree (SRT), which represents a roadmap of the explored area with an associated safe region. In SRT-Ball, the safe region is conservatively estimated as the maximum collision-free circle surrounding the robot in the workspace. We also present FB-SRT-Ball, a frontier-based version of SRT-Ball aimed at increasing the efficiency of exploration. The two strategies are critically compared by simulations