APPEARANCE-BASED VISUAL ODOMETRY WITH OMNIDIRECTIONAL IMAGES A Practical Application to Topological Mapping

In this paper we deal with the problem of map creation and localization of a mobile robot using omnidirectional images. We describe a real-time algorithm for topological mapping, using as input data only a set of images captured by a single omnidirectional camera mounted at a fixed position on the mobile robot. To compute the topological relationships between locations in the map, we use techniques based in the global appearance of the images. When using these methods, it is important to remove redundant information to get an acceptable computational cost when comparing locations. With this aim, we describe each omnidirectional image by a single Fourier descriptor that represents the appearance as well as the relative orientation between images. This algorithm permits computing the relative topological position of a location with respect to the previous one, acting as a visual compass. We have carried out a complete set of experiments to study the validity of the proposed visual odometry and topological mapping and to perform an objective comparison between the results obtained using the robot odometry, our visual odometry and the ground truth. We have also checked the time consumption to carry out the process and the geometrical accuracy obtained comparing to the ground truth.