Patent ID: 7066559
Filing Date: 2006-06-27
Classification: B60T

Abstract:
1. A brake pressure estimating apparatus for an automotive vehicle, comprising: a brake system including a master cylinder which develops a hydraulic in response to at least a brake manipulation as a hydraulic source and a brake pressure controlling section that is enabled to arbitrarily control a brake pressure of each wheel cylinder; a first wheel cylinder brake liquid pressure estimating section that estimates a first brake liquid pressure of the wheel cylinder of each of road wheels on the basis of a model of the brake pressure controlling section for each of control periods; a second wheel cylinder brake liquid pressure estimating section that estimates a second brake liquid pressure of the wheel cylinder for each road wheel on the basis of a vehicular model with a vehicular characteristic using a signal indicative of a road wheel acceleration as an element of a vehicular state for each control period; and a master cylinder liquid pressure estimating section that estimates a liquid pressure of the master cylinder for each control period on the basis of the first and second brake liquid pressure estimated values of the wheel cylinder of each road wheel estimated by the first wheel cylinder liquid pressure estimating section and the second wheel cylinder brake liquid pressure estimating section, the first wheel brake cylinder liquid pressure estimating section calculates the first brake liquid pressure of the wheel cylinder of each road wheel on the basis of the master cylinder liquid pressure estimated value estimated at a previous control period and the first liquid pressure estimated value estimated at the previous control period, the second wheel cylinder brake liquid pressure estimating section including a vehicular motion state detecting section that detects a vehicular motion state and calculating the second wheel cylinder brake liquid pressure for each road wheel from the detected vehicular motion state, and the master cylinder liquid pressure estimating section outputting the master cylinder liquid pressure estimated value to make a difference between the first wheel cylinder brake liquid pressure estimated value and the second wheel cylinder brake liquid pressure estimated value small to the first wheel cylinder brake liquid pressure estimating section to cause the master cylinder liquid pressure estimated value to be converged into a true value thereof.