We describe techniques for performing mobile robot localization using occupancy grids that allow subpixel localization and uncertainty estimation in the pixelized pose space. The techniques are based on a localization method where matching is performed between the visible landmarks at the current robot position and a previously generated map of the environment. A likelihood function over the space of possible robot positions is formulated as a function of the probability distribution for the map matching error. Subpixel localization and uncertainty estimation are performed by tting the likelihood function with a parameterized surface. The performance of the method is analyzed using synthetic experiments and an example is given using the Rocky 7 Mars rover prototype.
Clark F. Olson