METHOD AND DEVICE FOR DETECTING OFFSET ERROR OF ACCELERATION SENSOR, PRESENT POSITION DETECTION DEVICE FOR VEHICLE, AND NAVIGATION DEVICE

摘要

PROBLEM TO BE SOLVED: To make properly detectable an offset error specific to a sensor such as an acceleration sensor used for detecting a present position by self-contained navigation calculation and not requiring wiring to an ECU.;SOLUTION: A general expression of an output value S of an acceleration sensor is S=α+gsinθ+εS. Because a travel direction acceleration α is α=0 in a halting state of a vehicle, the output value S1 of the acceleration sensor measured according to measurement indication is S1=gsinθ+εS1 (S150). Then, an output value S2 of the acceleration sensor measured according to second measurement indication inputted in a state that the vehicle is halted with the vehicle back to front at the same position is S2=-gsinθ+εS2 (S180). The offset errors εS1, εS2 are values intrinsic to the sensor, and are constant regardless of a road surface condition. Accordingly, because εS1=εS2=εS is assumed, S1+S2=2εS is gotten. Hence, a mean value (S1+S2)/2 of the sensor output values S1, S2 is equal to the offset error εS (S190).;COPYRIGHT: (C)2000,JPO