Patent ID: 8326532

Claim:
A computer arrangement for determining and correcting for inaccurate global positioning system samples comprising: a processor arranged to communicate with a memory storing a computer program comprising instructions and data that can be run by the processor, said processor being arranged to perform at least the following actions when it runs said computer program: a) obtaining global positioning system samples as taken by a global positioning system on board a land based vehicle when traveling along a trajectory; b) obtaining a first estimation of said trajectory based on said global positioning system samples; c) obtaining a second estimation of said trajectory at least based on measurements made by an inertial measurement unit on board said land based vehicle when traveling along said trajectory; d) comparing said first and second estimations; e) establishing locations where said first estimation shows a variation compared with said second estimation above a predetermined threshold; f) if no such locations can be established continue with action j), otherwise continue with action g); g) removing global positioning system samples associated with said locations of high variation as being inaccurate global positioning system samples, thus forming a set of remaining global positioning system samples; h) calculating said first estimation anew of said trajectory based on said remaining global positioning system samples and calculating said second estimation anew; i) repeating actions d) to h); and j) ending said actions.