An exploration strategy using sonar sensors in corridor environments

We present a novel solution for topological exploration in corridor environments using cheap and error-prone sonar sensors. Topological exploration requires significant location detection and motion planning. To detect nodes (i.e., significant places) robustly, we propose a new measure, the eigenvalue ratio (EVR), which converts geometrical shapes in the environment into quantitative values using principal component analysis. For planning the safe motion of a robot, we propose the circle following (CF) method, which abstracts the geometry of the environment while taking the characteristics of the sonar sensors into consideration. Integrating the EVR with the CF method results in a topological exploration strategy using sonar sensors approach. The practicality of this approach is demonstrated by simulations and real experiments in corridor environments.