Method of modelling a tire in running conditions at a defined speed

Patent metadata

Field	Value
Publication number	US-2016207366-A1
Application number	US-201414909500-A
Country	US
Kind code	A1
Filing date	Jul 23, 2014
Priority date	Aug 2, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A method is provided for modelling a tire in running conditions at a defined speed. During running, the tire is subjected to a downward vehicle load (F z ) representing a vehicle and to a transverse thrust stress (F y ), and the tire is inclined with respect to a vertical direction by a camber angle (γ). The method includes modelling an overturning moment (Mx) exerted on the tire, in which the overturning moment (Mx) is a sum of at least:
a moment (Mx 1 ) produced by an offset of the vehicle load (F z ) by the camber angle (γ); a moment (Mx 2 ) produced by the transverse thrust stress (F y ); a moment (Mx 3 ) produced by a ground reaction (F R ) under the vehicle load (F z ), with the ground reaction (F R ) being decentred from a reference point (C) of the tire by the transverse thrust stress (F y ).

First claim

1 - 7 . (canceled)

8 : A method of modelling a tire in running conditions at a defined speed, the tire being subjected to a downward vehicle load (F z ) representing a vehicle and to a transverse thrust stress (F y ), and the tire being inclined with respect to a vertical direction by a camber angle (γ), the method comprising the steps of:
calculating a moment (Mx 3 ) produced by a ground reaction (F R ) of the tire under the vehicle load (F z ); and
modelling an overturning moment (Mx) exerted on the tire as a sum of at least:
a moment (Mx 1 ) produced by an offset of the vehicle load (F z ) by the camber angle (γ),
a moment (Mx 2 ) produced by the transverse thrust stress (F y ), and
the moment (Mx 3 ) produced by the ground reaction (F R ) of the tire under the vehicle load (F z ),

wherein the ground reaction (F R ) of the tire is decentered from a reference point (C) of the tire by the transverse thrust stress (F y ), and
wherein, in the calculating step, the moment (Mx 3 ) is calculated by a formula having a form of:

Mx
31

+

Mx
32

×

(

F
z

-

Mx
33

)

×
γ

+

F
z

×

arctan


(

Mx
34

×
δ
×

F
z

)

×

Mx
35

×

(

1
+

Mx
36

×
V

)

×

(

1
+

Mx
37

×

(

Mx
38

-
P

)

Mx
38

)

,

where Mx 31 , Mx 32 , Mx 33 , Mx 34 , Mx 35 , Mx 36 , Mx 37 and Mx 38 are predefined coefficients, F z is the vehicle load, γ is the camber angle, δ is a drift angle, V is a speed, and P is an inflation pressure.

9 : The method according to claim 8 ,
wherein the drift angle (δ) and the inflation pressure (P) are quantities corresponding to the tire, and wherein the moment (Mx 3 ) is a function of the vehicle load (F z ), the speed (V), the camber angle (γ), the drift angle (δ), and the inflation pressure (P).

10 : The method according to claim 8 , wherein the coefficients Mx 31 , Mx 31 , Mx 32 , Mx 33 , Mx 34 , Mx 35 , Mx 36 , Mx 37 and Mx 38 are predefined during a preliminary step that includes:
performing bench measurements of the tire, and then iteratively adjusting the coefficients until a model reproduces the bench measurements to within a predefined error margin.

11 : The method according to claim 8 , wherein the method is used to define a behaviour of a vehicle equipped with the tire.

12 : The method according to claim 11 , wherein the behaviour of the vehicle when rolling over is defined.

13 : A computer-readable storage medium storing a program that, when read by a computer and executed by a computer processor, performs a method of modelling a tire in running conditions at a defined speed, the tire being subjected to a downward vehicle load (F z ) representing a vehicle and to a transverse thrust stress (F y ), and the tire being inclined with respect to a vertical direction by a camber angle (γ), the method comprising steps of:
calculating a moment (Mx 3 ) produced by a ground reaction (F R ) of the tire under the vehicle load (F z ); and
modelling an overturning moment (Mx) exerted on the tire as a sum of at least:
a moment (Mx 1 ) produced by an offset of the vehicle load (F z ) by the camber angle (γ),
a moment (Mx 2 ) produced by the transverse thrust stress (F y ), and
the moment (Mx 3 ) produced by the ground reaction (F R ) of the tire under the vehicle load (F z ),

wherein the ground reaction (F R ) of the tire is decentered from a reference point (C) of the tire by the transverse thrust stress (F y ), and
wherein, in the calculating step, the moment (Mx 3 ) is calculated by a formula having a form of:

Mx
31

+

Mx
32

×

(

F
z

-

Mx
33

)

×
γ

+

F
z

×

arctan


(

Mx
34

×
δ
×

F
z

)

×

Mx

Assignees

• Michelin & Cie
• Michelin Rech Tech

Inventors

• Buisson Jérémy
• Virin Teddy

Classifications

• G06F30/15

  Vehicle, aircraft or watercraft design · CPC title

• G06F30/20

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• G06F2111/10

  Numerical modelling · CPC title

• B60C99/006 Primary

  Computer aided tyre design or simulation · CPC title

• G06F17/5095

  Physics · mapped topic