1. A method of localizing an autonomous object in a space, comprising: retrieving from data storage a digital map of the space; with a localizing module run by a controller, identifying a plurality of potential locations for the autonomous object in the space; with the localizing module based on the digital map, generating a prediction of expected ranges between the autonomous object when at each of the potential locations and surfaces in the space, wherein the generating of the predictions includes generating a ray casting prediction from the autonomous object to the surfaces in the space; operating a ranging device to measure ranges between the autonomous object and the surfaces in the space; and comparing, for each of the predictions, the measured ranges with the expected ranges to identify one of the predictions as an accurate prediction, wherein the comparing includes weighting each of the measured ranges based on results of the comparing.