Patent ID: 9423261
Filing Date: 2016-08-23
CPC Classification: G01C

Claim Text:
1. A method comprising: obtaining a first spline representing a path from a map database; generating a second spline based on measured position data collected while traversing the path; performing, with a processor, an alignment between a section of the first spline spanning a geographic distance and a section of the second spline corresponding the geographic distance, wherein the section of the first spline corresponds geographically to the section of the second spline; calculating, with a processor, a relative error (RE) between a first attribute (A1) for the section of the first spline spanning a geographic distance and a second attribute (A2) for the section of the second spline corresponding the geographic distance according to: wherein the section of the first spline corresponds geographically to the section of the second spline; assigning a confidence factor for a navigation feature to the section of the first spline based on the relative error; identifying a section of the second spline corresponding the geographic distance; comparing the section of the second spline based on measured position data to a minimum curve threshold, wherein when the section of the second spline exceeds the minimum curve threshold, the alignment is performed, and when the section of the second spline is less than the minimum curve threshold, the section of the second spline is excluded from alignment; and reporting the confidence factor to a map developer.