Back to results
US 12,325,406 B2Granted
Braking control system and method for vehicle
AssigneesHyundai Motor Company, Kia Motors Corporation
InventorHee Jin Cho
Life of this patent
Estimating the term…
Abstract
A braking control system and method for a vehicle are configured to calculate a braking force of front and rear wheels using a wheel slip ratio of the front and rear wheels and a road surface friction coefficient and then accurately estimate and calculate a disk temperature of the front and rear wheels using a predetermined estimation formula from the calculated braking force, and control distribution of braking pressure to the front wheels and the rear wheels so as to uniformly wear brake pads based on the calculated temperatures of the disks.
Claims20
A braking control system for a vehicle, comprising:
- a wheel speed sensor configured to detect a wheel speed of front wheels and rear wheels;
- and
- a controller configured to sequentially perform calculating a wheel slip ratio based on a wheel speed signal detected by the wheel speed sensor, extracting a road surface friction coefficient matching the calculated wheel slip ratio from mapping table data, calculating braking force of the front wheels and the rear wheels using vehicle data information in addition to the extracted road surface friction coefficient, wherein the vehicle data information includes road friction coefficients of the front wheels and the rear wheels, axial loads of the front and rear wheels, height to a center of gravity of the vehicle from a road surface, a distance between centers of tires of the front and rear wheels, a vehicle weight, deceleration and a front-wheel braking force, calculating temperatures of disks of the front wheels and the rear wheels using the calculated braking force of the front wheels and the rear wheels and a disk temperature estimation formula, and controlling a distribution of braking pressure to the front wheels and the rear wheels based on a calculated temperature difference between the disks of the front wheels and the rear wheels.
A braking control method for a vehicle, the method comprising:
- detecting, by a wheel speed sensor, a wheel speed of front wheels and rear wheels;
- calculating, by a controller, a wheel slip ratio based on a wheel speed signal detected by the wheel speed sensor;
- extracting, by the controller, a road surface friction coefficient matching the calculated wheel slip ratio from mapping table data;
- calculating, by the controller, braking force of the front wheels and the rear wheels using vehicle data information in addition to the extracted road surface friction coefficient, wherein the vehicle data information includes road friction coefficients of the front wheels and the rear wheels, axial loads of the front and rear wheels, height to a center of gravity of the vehicle from a road surface, a distance between centers of tires of the front and rear wheels, a vehicle weight, deceleration, and a front-wheel braking force;
- calculating, by the controller, temperatures of disks of the front wheels and the rear wheels using the calculated braking force of the front wheels and the rear wheels and a disk temperature estimation formula;
- and
- controlling, by the controller, a distribution of braking pressure to the front wheels and the rear wheels based on a calculated temperature difference between the disks of the front wheels and the rear wheels.
4 more elements
A braking control system for a vehicle, comprising:
- a wheel speed sensor configured to detect a wheel speed of front wheels and rear wheels;
- and
- a controller configured to sequentially perform calculating a wheel slip ratio based on a wheel speed signal detected by the wheel speed sensor, extracting a road surface friction coefficient matching the calculated wheel slip ratio from mapping table data, calculating braking force value of the front wheels and the rear wheels using vehicle data information in addition to the extracted road surface friction coefficient, calculating temperatures of disks of the front wheels and the rear wheels using the calculated braking force value of the front wheels and the rear wheels and a disk temperature estimation formula, and controlling a distribution of braking pressure to the front wheels and the rear wheels based on a calculated temperature difference between the disks of the front wheels and the rear wheels,
- wherein when calculating the braking force value of the front wheels and the rear wheels, the controller is configured to calculate the braking force value using Equations 2 and 3 below:
- μ
- TF
- =
- F
- xF
- W
- F
- +
- h
- L
- ·
- W
- ·
- a
- [
- Equation
-
- 2
- ]
- wherein in Equation 2 above, μTF is a road surface friction coefficient of a front wheel, WF is a front wheel axial load, h is a height to a center of gravity of a vehicle from a road surface, L is a distance between centers of tires of the front wheel and rear wheel, W is a vehicle weight, a is deceleration, and FxF is a front-wheel braking force, and
- μ
- TR
- =
- F
- xR
- W
- R
- -
- h
- L
- ·
- W
- ·
- a
- [
- Equation
-
- 3
- ]
- wherein in Equation 3 above, μTR is a road surface friction coefficient of the rear wheel, WR is a rear wheel axial load, h is a height to a center of gravity of the vehicle from the road surface, L is a distance between centers of the tires of the front wheel and the rear wheel, W is a vehicle weight, a is deceleration, and FxR is a rear-wheel braking force.
41 more elements
A braking control system for a vehicle, comprising:
- a wheel speed sensor configured to detect a wheel speed of front wheels and rear wheels;
- and
- a controller configured to sequentially perform calculating a wheel slip ratio based on a wheel speed signal detected by the wheel speed sensor, extracting a road surface friction coefficient matching the calculated wheel slip ratio from mapping table data, calculating braking force value of the front wheels and the rear wheels using vehicle data information in addition to the extracted road surface friction coefficient, calculating temperatures of disks of the front wheels and the rear wheels using the calculated braking force value of the front wheels and the rear wheels and a disk temperature estimation formula, and controlling a distribution of braking pressure to the front wheels and the rear wheels based on a calculated temperature difference between the disks of the front wheels and the rear wheels,
- wherein the calculating temperatures of disks of the front wheels and the rear wheels using the calculated braking force value of the front wheels and the rear wheels and a disk temperature estimation formula includes:
- a first step of calculating a disk braking force energy using the braking force of the front wheels and the rear wheels,
- a second step of calculating a disk input energy including the disk braking force energy as calculated in the first step,
- a third step of calculating of an increased disk temperature using a first estimation formula into which the disk input energy calculated is inserted,
- a fourth step of calculating a disk temperature change using a second estimation formula into which the increased disk temperature calculated using the first estimation formula is inserted, and
- a fifth step of calculating a disk temperature using a third estimation formula into which the disk temperature change calculated using the second formula is inserted.
6 more elements
Dependencies are inferred from the claim text.