Patent ID: 6466855
Filing Date: 2002-10-15
Classification: B60T

Abstract:
An apparatus for estimating a vehicle speed of a vehicle in which a driving state can be switched between an all-wheel driving state where all wheels of the vehicle are driven wheels, and a selected-wheel driving state where a first group of wheels are driven wheels and a second group of wheels are non-driven wheels, comprising a controller that:determines the driving state of the vehicle; calculates the vehicle speed based on at least a wheel speed of at least one of the non-driven wheels when it is determined that the driving state is the selected-wheel driving state; and when it is determined that the driving state is not the selected-wheel driving state or when it cannot be determined that the driving state is the selected-wheel driving state, calculates the vehicle speed based on at least a wheel speed of at least one of the wheels of the vehicle, the number of the at least one of the wheels being equal to or smaller than that of the non-driven wheels (N), and the at least one of the wheels having the lowest to the Nth lowest one of the wheel speeds of all of the wheels.