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US 7,066,559 B2Granted
Brake pressure estimating apparatus and method
AssigneeHitachi, Ltd.
InventorMasamichi Imamura
Life of this patent
Estimating the term…
Abstract
In brake pressure estimating method and apparatus for an automotive vehicle, at a second wheel cylinder brake liquid pressure estimating, a vehicular state is detected and the second wheel cylinder brake liquid pressure for each road wheel is calculated from the detected vehicular motion state, and, at a master cylinder liquid pressure estimating, a master cylinder liquid pressure estimated value is outputted to make a difference between a first wheel cylinder brake liquid pressure estimated value based on a vehicle model and the second wheel cylinder brake liquid pressure estimated value based on a hydraulic unit model small to cause the master cylinder liquid pressure estimated value to be converged into a true value thereof.
Claims26
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.
2 more elements
A brake pressure estimating method for an automotive vehicle, the automotive vehicle comprising:
- a brake system including a brake liquid pressure generator which develops a brake liquid pressure at each wheel cylinder of a road wheel and a brake pressure controlling section that is enabled to arbitrarily control a brake pressure of each wheel cylinder, the brake pressure estimating method comprising:
- estimating a first brake liquid pressure of the wheel cylinder of each road wheel on the basis of a model of the brake pressure controlling section for each control period;
- estimating a second brake liquid pressure of the wheel cylinder for each of road wheels 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 of control periods;
- and
- estimating a liquid pressure of the brake liquid pressure generator 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, at the first wheel cylinder liquid pressure estimating, calculating the first brake liquid pressure of the wheel cylinder of each road wheel on the basis of a brake pressure generator estimated value estimated at a previous control period and the first brake liquid pressure estimated value estimated at the previous control period, at the second wheel cylinder brake liquid pressure estimating, detecting a vehicular motion state and calculating the second wheel cylinder brake liquid pressure for each road wheel from the detected vehicular motion state, and, at the brake liquid pressure generator estimating, outputting the brake liquid pressure generator 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 cause the brake liquid pressure generator estimated value to be converged into a true value thereof.
2 more elements
A brake pressure estimating apparatus for an automotive vehicle, comprising:
- a brake system comprising
- a brake liquid pressure generator which develops a brake liquid pressure at each wheel cylinder of a road wheel, and
- a brake pressure controlling section configured to arbitrarily control the brake pressure of each wheel cylinder;
- a brake liquid pressure estimating section comprising
- a first brake liquid pressure estimating section that estimates a first brake liquid pressure of the wheel cylinder (P^WC) on the basis of a brake pressure controlling model,
- a second brake liquid pressure estimating section that estimates a second brake liquid pressure of the wheel cylinder (PB) on the basis of a vehicular model having a vehicular characteristic that uses a signal indicative of a road wheel acceleration as an element of a vehicular state, and
- a third brake liquid pressure estimating section that estimates a third brake liquid pressure of a brake generator (P^MC) on the basis of the first and the second brake liquid pressure of the wheel cylinder (P^WC, PB), wherein the brake pressure estimating section estimates the third brake liquid pressure of the brake generator (P^MC) regardless of whether the brake pressure controlling section is executed.
4 more elements
A brake pressure estimating apparatus for an automotive vehicle, comprising:
- a brake system comprising
- a brake liquid pressure generator which develops a brake liquid pressure at each wheel cylinder of a road wheel, and
- a brake pressure controlling section configured to arbitrarily control the brake pressure of each wheel cylinder;
- a brake liquid pressure estimating section comprising
- a first brake liquid pressure estimating section that estimates a first brake liquid pressure of the wheel cylinder (P^WC) on the basis of a model of a brake pressure controlling model,
- a second brake liquid pressure estimating section that estimates a second brake liquid pressure of the wheel cylinder (PB) on the basis of a vehicular model having a vehicular characteristic that uses a signal indicative of a road wheel acceleration as an element of a vehicular state, and
- a third brake liquid pressure estimating section that estimates a third brake liquid pressure of a brake generator (P^MC) on the basis of the first and the second brake liquid pressure of the wheel cylinder (P^WC, PB), wherein the brake liquid pressure estimating section estimates the third brake liquid pressure of a master cylinder (P^MC) even without manipulation of a brake pedal.
4 more elements
A brake pressure estimating apparatus for an automotive vehicle, comprising:
- a brake system comprising
- a brake liquid pressure generator which develops a brake liquid pressure at front road wheel side and rear road wheel side wheel cylinders of four road wheels, and
- a brake pressure controlling sections that is enabled to arbitrarily control the brake pressure of each wheel cylinder;
- a brake liquid pressure estimating section comprising
- a first brake liquid pressure estimating section that estimates a first front road side and rear road side brake liquid pressure of the respective front road side and rear road side wheel cylinders (P^WC) on the basis of a model of the brake pressure controlling model,
- a second brake liquid pressure estimating section that estimates a second front road side and rear road side brake liquid pressure of the respective front road side and rear road side wheel cylinders (PB) on the basis of a vehicular model with a vehicular characteristic that uses a signal indicative of a road wheel acceleration as an element of a vehicular state, and
- a third brake liquid pressure estimating section that includes a front road side gain and a rear road side gain, whose value is smaller than that of the front road side gain and estimates a third brake liquid pressure of a brake generator (P^MC) on the basis of the first and the second brake liquid pressure of the respective front road side and rear road side wheel cylinders (P^WC, PB) using the front road side gain and the rear road side gain.
4 more elements
A brake pressure estimating apparatus for an automotive vehicle, comprising:
- a brake system comprising
- a brake liquid pressure generator which develops a brake liquid pressure at each wheel cylinder of a road wheel, and
- a brake pressure controlling section configured to arbitrarily control the brake pressure of each wheel cylinder;
- a brake liquid pressure estimating section comprising
- a sudden brake determination section that determines whether a sudden brake occurs,
- a first brake liquid pressure estimating section that estimates a first brake liquid pressure of the wheel cylinder (PWC) on the basis of a brake pressure controlling model,
- a second brake liquid pressure estimating section that estimates a second brake liquid pressure of the wheel cylinder (PB) on the basis of a vehicular model, and
- a third brake liquid pressure estimating section that estimates a third brake liquid pressure of a brake generator (P^MC) on the basis of the first and the second brake liquid pressure, wherein the third liquid pressure estimating section sets the lower limit value of the third brake liquid pressure as a maximum value of the first brake liquid pressure of the wheel cylinder (P^WC, PB) when the sudden brake is determined.
5 more elements
A brake pressure estimating apparatus for an automotive vehicle, comprising:
- a brake system comprising
- a brake liquid pressure generator which develops a brake liquid pressure at each wheel cylinder of a road wheel, and
- a brake pressure controlling section that is enabled to arbitrarily control the brake pressure of each wheel cylinder;
- a brake liquid pressure estimating section comprising
- a brake release determination section that determines whether a brake release occurs,
- a first brake liquid pressure estimating section that estimates a first brake liquid pressure of the wheel cylinder (P^WC) on the basis of a brake pressure controlling model,
- a second brake liquid pressure estimating section that estimates a second brake liquid pressure of the wheel cylinder (PB) on the basis of a vehicular model, and
- a third brake liquid pressure estimating section that estimates a third brake liquid pressure of a brake generator (P^MC) on the basis of the first and the second brake liquid pressure, wherein the third liquid pressure estimating section sets the upper limit value of the third brake liquid pressure as a maximum value of the first brake liquid pressure of the wheel cylinder (P^WC, PB) when the brake release is determined.
5 more elements
Dependencies are inferred from the claim text.