Tire suspension fusion system for estimation of tire deflection and tire load

Patent metadata

Field	Value
Publication number	US-9874496-B2
Application number	US-201313795761-A
Country	US
Kind code	B2
Filing date	Mar 12, 2013
Priority date	Mar 12, 2013
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

A system and method estimating a vehicle tire load includes a tire static load estimator estimating a static tire load using a tire attached TPMS sensor; a Kalman filter based tire deflection estimator estimating tire vertical deflection; a load variation estimator estimating the instantaneous load variation by using the tire vertical deflection information; and an output tire load estimator calculating an output load estimation mathematically by fusing the static tire load with the instantaneous load variation information. The tire deflection estimator includes a chassis accelerometer measuring a chassis vertical acceleration; and a hub accelerometer measuring a wheel hub vertical acceleration of the tire. A linear filter model receives as inputs the chassis vertical acceleration and the wheel hub vertical acceleration.

First claim

What is claimed is:

1. A tire load estimation system for a vehicle comprising:
at least one tire mounted to a wheel hub and supporting a vehicle chassis;
at least one tire static load sensor mounted to the at least one tire for detecting a measured static tire load;
a tire static load estimator for calculating an estimated tire static load on the at least one tire based on the measured static tire load;
at least one vehicle chassis-mounted sensor for measuring a vehicle chassis vertical deflection;
a tire deflection estimator for determining a tire vertical deflection estimate from the estimated tire static load and the vehicle chassis vertical deflection;
a load variation estimator for determining a load variation estimate from the tire vertical deflection estimate; and
a tire load estimator operative to determine a substantially instantaneous load on the at least one tire based on the estimated tire static load and the load variation estimate.

2. The tire load estimation system of claim 1 , wherein further comprising:
a tire inflation pressure measuring sensor mounted to the at least one tire for measuring tire inflation pressure within a tire cavity of the at least one tire;
a tire-specific stiffness database adjusted for tire inflation pressure for identifying a tire-specific stiffness for the at least one tire at the measured tire air pressure;
a tire vertical stiffness estimator for estimating a tire vertical stiffness from the tire inflation pressure and the tire-specific stiffness for the at least one tire; and wherein the tire deflection estimator operably uses as an input the tire-specific vertical stiffness in estimating the tire vertical deflection.

3. The tire load estimation system of claim 2 , wherein the at least one tire static load sensor comprises at least one tire-mounted sensor for measuring a rolling tire footprint length.

4. The tire load estimation system of claim 1 , wherein the at least one vehicle chassis-mounted sensor for measuring a vehicle chassis vertical deflection comprises a chassis acceleration measuring sensor for measuring a chassis vertical acceleration; and a hub acceleration measuring sensor for measuring a vertical acceleration of the wheel hub of the at least one tire.

5. The tire load estimation system of claim 4 , wherein the tire deflection estimator comprises a linear filter model receiving as inputs the chassis vertical acceleration and the wheel hub vertical acceleration.

6. The tire load estimation system of claim 5 , wherein the linear filter model comprises a Kalman filter model.

7. The tire load estimation system of claim 5 , wherein further comprising:
a tire inflation pressure measuring sensor mounted to the at least one tire for measuring a tire inflation pressure within a tire cavity of the at least one tire;
a tire-specific stiffness database for identifying a tire-specific stiffness for the at least one tire at the measured tire inflation pressure; and
a tire vertical stiffness estimator for estimating a tire vertical stiffness from the measured tire air pressure and the tire-specific stiffness for the at least one tire; and wherein the linear filter model operably uses as an input the tire vertical stiffness in estimating the tire vertical deflection estimate.

8. A tire load estimation system for a vehicle comprising:
at least one tire mounted to a wheel hub and supporting a vehicle chassis;
at least one load sensor mounted to the at least one tire for detecting a measured tire load on the at least one tire;
a tire static load estimator operable to determine a static tire load from the measured tire load;
at least one vehicle chassis-mounted sensor for measuring a vehicle chassis vertical deflection;
a tire deflection estimator operable to estimate a tire deflection by fusing the static load estimation of the at least one tire with the vehicle chassis vertical deflection;
a load variation estimator for estimating a substantially instantaneous load variation from the estimated tire deflection;
a tire load estimator for calculating a substantially instantaneous tire load estimation operably fusing the static tire load with the instantaneous load variation.

9. The tire load estimation system of claim 8 , wherein the at least one static load sensor comprises at least one tire-attached sensor for measuring a length of a rolling tire footprint.

10. The tire load estimation system of claim 8 , wherein the at least one vehicle chassis-mounted sensor for measuring the vehicle chassis vertical deflection comprises a chassis vertical acceleration measuring sensor for measuring a chassis vertical acceleration; and a hub acceleration measuring sensor for measuring a vertical acceleration of the wheel hub of the at least one tire.

11. The tire load estimation system of claim 10 , wherein the tire deflection estimator comprises a linear filter model receiving as inputs the vehicle chassis vertical acceleration and the wheel hub vertical acceleration.

12. The tire load estimation system of claim 11 , wherein the linear filter model comprises a Kalman filter model.

13. A method of estimating a tire load for a vehicle comprising:
supporting a vehicle chassis by at least one tire mounted to a wheel hub;
detecting a measured static tire load by a tire static load sensor mounted to the at least one tire;
calculating an estimated tire static load based on the measured static tire load;
detecting a measured vehicle chassis vertical deflection from a sensor mounted to the vehicle chassis;
estimating a tire vertical deflection from the vehicle chassis vertical deflection and the static tire load;
calculating an estimated load variation from the tire vertical deflection estimation; and
estimating a substantially instantaneous tire load on the at least one tire based on the estimated tire static load and the estimated load variation.

14. The method of claim 13 , wherein further comprising:
measuring a tire inflation pressure within a tire cavity;
identifying from a tire-specific stiffness database a tire-specific stiffness for the at least one tire using the measured tire inflation pressure.

15. The method of claim 14 , wherein further comprising measuring a rolling tire footprint length to determine the measured static tire load.

16. The method of claim 14 , wherein further comprising:
measuring a vertical acceleration of the vehicle chassis; and
measuring a vertical acceleration of the wheel hub to which the at least one tire;
estimating the tire vertical deflection from the static load estimation, vertical acceleration of the vehicle chassis, and vertical acceleration of the wheel hub.

17. The method of claim 16 , wherein further comprising using a linear filter model to estimate the tire vertical deflection.

Assignees

• Goodyear Tire & Rubber

Inventors

• Singh Kanwar Bharat

Classifications

• B60C23/064

  comprising tyre mounted deformation sensors, e.g. to determine road contact area · CPC title

• B60C23/0488 Primary

  Movement sensor, e.g. for sensing angular speed, acceleration or centripetal force · CPC title

• G01M17/02 Primary

  Tyres · CPC title

• B60C23/065

  by monitoring vibrations in tyres or suspensions (B60C23/062 takes precedence) · CPC title