Patent ID: 6049761
Filing Date: 2000-04-11
Classification: G01C

Abstract:
An electronic apparatus for measuring a traveling direction of a vehicle in cycles, comprising:a geomagnetic sensor mounted to the vehicle for detecting geomagnetism around the vehicle and outputting electric signals corresponding to the geomagnetism;an electronic calculator receiving the electric signals from the geomagnetic sensor, said calculator including:current cycle value deriving means for deriving a current cycle value of a coordinate position of the geomagnetism detected by the geomagnetic sensor based on the electric signals,deviation magnitude deriving means for deriving a magnitude of a deviation between the current cycle value and an item associated with a standard azimuth circle,weight setting means for setting a weighting for the current cycle value of the geomagnetism and a prior cycle value of the geomagnetism depending on the magnitude of the deviation in each cycle such that the current cycle value has a smaller weight than the prior cycle value as the magnitude of the deviation increases,mean data deriving means for deriving mean data from said current cycle value and said prior cycle value using said weighting, andtraveling direction deriving means for deriving the traveling direction of the vehicle based on said mean data; andmeans for producing a signal indicating a traveling direction of the vehicle based on an output of said traveling direction deriving means.