The localization problem for mobile robots

A fundamental task for an autonomous mobile robot is that of localization-determining its location in a known environment. This problem arises in settings that range from the computer analysis of aerial photographs to the design of autonomous Mars rovers. L. Guibas et al. ((1992) have given geometric algorithms for the problem of enumerating locations for a robot consistent with a given view of the environment. We provide an on-line algorithm for a robot to move within its environment so as to uniquely determine its location. The algorithm improves asymptotically on strategies based purely on the “spiral search” technique of R. Baeza-Yates et al. (1993); an interesting feature of our approach is the way in which the robot is able to identify “critical directions” in the environment which allow it to perform late stages of the search more efficiently