METHOD AND SYSTEM OF RECOGNIZING SIGN OF VELOCITY OF VEHICLE TO ESTIMATE SLOPE OF ROAD

PROBLEM TO BE SOLVED: To provide a method and system of recognizing the sign of velocity of a vehicle to estimate the slope of a road. SOLUTION: A method of estimating the slope of a road is as follows: (a) providing a signal indicating the measurement of the velocity of the vehicle by a velocity sensor means; (b) providing a signal indicating the measurement of the acceleration in the longitudinal direction of the vehicle by an acceleration measurement means; (c) processing the velocity measurement signal and the acceleration measurement signal by means of a prescribed mathematical model, thereby determining an estimated value of the slope of the road; (d) processing the velocity measurement signal, the acceleration measurement signal and the estimated value of the slope, thereby determining the sign of the velocity of the vehicle; and (e) repeating operations (a) to (d) recursively according to a predetermined rule, in which the sign of the velocity determined in operation (d) of a specific recursive step is used as an additional input for operation (c) of the successive recursive step to renew the estimated value of the slope of the road. COPYRIGHT: (C)2007,JPO&INPIT