Abstract: In a preferred embodiment, a vehicle position uncertainty area correction method and a corresponding apparatus are detailed. This method is preferably executed on a hardware platform 400. This method includes provision of an initial position envelope (307) associated with a vehicle position. Then, a corrected position envelope (307"") is derived from the initial position envelope (307) and bounded within a predetermined fixed area (313, 315) surrounding an outermost pair (305, 309) of road segments. The outermost pair (305, 309) of road segments are extracted from a map database (415) positioned within boundaries delimited by the position envelope (307).

Abstract: An improved accuracy sensory system for vehicle navigation employs a sensor, such as a compass (515), or an odometer (509), for sensing a navigation parameter of a vehicle. A signal is provided from the sensor, having an erroneous component. A model free recognizer, such as a fuzzy inferencing navigation computer (501), is employed to recognize this erroneous behavior. After recognition, the sensor can be recalibrated, or assigned a clearness coefficient. The signal is then combined with other measurements of the same parameter and subjected to map matching before deriving the final navigation variable.