Systems and methods for neural ordinary differential equation learned tire models

Patent metadata

Field	Value
Publication number	US-12252139-B2
Application number	US-202318182494-A
Country	US
Kind code	B2
Filing date	Mar 13, 2023
Priority date	Mar 13, 2023
Publication date	Mar 18, 2025
Grant date	Mar 18, 2025

Abstract

System, methods, and other embodiments described herein relate to NODE learned tire models. In one embodiment, a method includes calculating estimated tire forces based on vehicle measurements; solving a second order differential equation in a repetitive manner until an error calculation based on a tire force function and the estimated tire forces reaches a minimum value, by: using a first predictive model to provide one or more inflection points and initial conditions based on the vehicle measurements, using a second and third predictive model to act as, respectively, exponents to a positive and a negative exponential equation based on the one or more inflection points, the initial conditions, and the vehicle measurements, and integrating the exponential equations to obtain the tire force function; and applying the tire force function to new vehicle measurements to estimate current tire forces.

First claim

What is claimed is:

1. A method comprising:
receiving estimated tire forces and vehicle measurements;
solving a second order differential equation in a repetitive manner until an error calculation based on a tire force function and the estimated tire forces reaches a minimum value, by:
using a first predictive model to provide one or more inflection points and initial conditions based on the vehicle measurements,
using a second and third predictive model to act as, respectively, exponents to a positive and a negative exponential equation based on the one or more inflection points, the initial conditions, and the vehicle measurements, and
integrating the exponential equations to obtain the tire force function; and

wherein the tire force function when applied to further vehicle measurements provides a tire force estimate.

2. The method of claim 1 , wherein solving the second order differential equation further includes using a fourth predictive model to obtain scaling parameters for estimating a lateral tire force function or a longitudinal tire force function from the tire force function.

3. The method of claim 2 , further comprising generating a fifth predictive model to replicate the tire force function.

4. The method of claim 2 , further comprising receiving the tire force estimate from the tire force function and adjusting a vehicle control input based on the tire force estimate.

5. The method of claim 2 , further comprising selecting a confidence parameter.

6. The method of claim 1 , further comprising generating a fourth predictive model to replicate the tire force function.

7. The method of claim 1 , further comprising receiving the tire force estimate from the tire force function and adjusting a vehicle control input based on the tire force estimate.

8. The method of claim 1 , further comprising selecting a confidence parameter.

9. A system comprising:
a processor; and
a memory storing instructions that, when executed by the processor, cause the processor to:
receive estimated tire forces and vehicle measurements;
solve a second order differential equation in a repetitive manner until an error calculation based on a tire force function and the estimated tire forces reaches a minimum value, by:
using a first predictive model to provide one or more inflection points and initial conditions based on the vehicle measurements,
using a second and third predictive model to act as, respectively, exponents to a positive and a negative exponential equation based on the one or more inflection points, the initial conditions, and the vehicle measurements, and
integrating the exponential equations to obtain the tire force function; and

wherein the tire force function when applied to further vehicle measurements provides a tire force estimate.

10. The system of claim 9 , wherein the instruction to solve the second order differential equation further includes using a fourth predictive model to obtain scaling parameters for estimating a lateral tire force function or a longitudinal tire force function from the tire force function.

11. The system of claim 10 , wherein the instructions further include an instruction to generate a fifth predictive model to replicate the tire force function.

12. The system of claim 10 , wherein the instructions further include instructions to:
receive the tire force estimate from the tire force function; and
adjust a vehicle control input based on the tire force estimate.

13. The system of claim 10 , wherein the instructions further include an instruction to select a confidence parameter.

14. The system of claim 9 , wherein the instructions further include an instruction to generate a fourth predictive model to replicate the tire force function.

15. The system of claim 9 , wherein the instructions further include instructions to:
receive the tire force estimate from the tire force function; and
adjust a vehicle control input based on the tire force estimate.

16. The system of claim 9 , wherein the instructions further include an instruction to select a confidence parameter.

17. A system comprising:
a processor; and
a memory storing instructions that, when executed by the processor, cause the processor to:
receive vehicle measurements, one or more inflection points, and initial conditions;
apply a first and second predictive model to act as, respectively, exponents to a positive and a negative exponential equation based on the one or more inflection points, the initial conditions, and the vehicle measurements; and
perform integration of the exponential equations to obtain a tire force estimate.

18. The system of claim 17 , wherein the instructions further include to apply scaling parameters to estimate a lateral tire force estimate or a longitudinal tire force estimate from the tire force estimate.

19. The system of claim 18 , wherein the instructions further include to adjust a vehicle control input based on the lateral tire force estimate, the longitudinal tire force estimate, or the tire force estimate.

20. The system of claim 17 , wherein the instructions further include to adjust a vehicle control input based on the tire force estimate.

Assignees

• Toyota Res Inst Inc
• Toyota Motor Co Ltd

Inventors

• Goh Yan Ming Jonathan
• Djeumou Franck

Classifications

• G06N5/022

  Knowledge engineering; Knowledge acquisition · CPC title

• G06F7/64 Primary

  Digital differential analysers, i.e. computing devices for differentiation, integration or solving differential or integral equations, using pulses representing increments; Other incremental computing devices for solving difference equations (G06F7/70 takes precedence; differential analysers using hybrid computing techniques G06J1/02 {; DDA application in numerical control G05B19/18}) · CPC title

• B60W2530/201

  Dimensions of vehicle · CPC title

• B60W40/101

  Side slip angle of tyre · CPC title

• B60W50/0097 Primary

  Predicting future conditions · CPC title