Patent ID: 6999859
Filing Date: 2006-02-14
Classification: G01P

Abstract:
1. A vehicle speed measuring apparatus for a vehicle comprising: vibration detection sensors for detecting vibrations from a road surface through tires, the vibration detection sensors being provided at front and rear wheel sides, respectively; an input section through which the vibration detection sensors input their detection values; and a processing unit for calculating vehicle speed of the vehicle based on a change pattern of the detection values inputted, wherein the processing unit operates in order: to feature extract a change pattern of the detection values for the respective front and rear wheel sides by excluding inherent tire influences on the detection values when the detection values are inputted through the input section; to execute pattern matching between the front and rear wheel sides on the basis of the feature extracted change patterns of the detection values; to obtain a time difference from a coincidence of the change patterns; and to calculate vehicle speed based on the time difference and a reference distance that is previously stored in the vehicle speed measuring apparatus.