METHOD FOR SIMULATING A ROLLING RADIUS OF A MOTOR VEHICLE TIRE
The invention relates to a method for producing a motor vehicle tire, comprising a step of estimating the effective rolling radius R roll of the tire by using a formula of the form in which: Rroll 1 = Rroll 11 - [ ( κ 11 + κ 12 * deflect Pg ) ] * ( 1 - exp ( - deflect Pg * Rroll 16 ) ) Rroll 2 = ( Rroll 21 + Rroll 22 * sign ( δ ) * V ) * 1 Fz Rroll 23 * ( 1 - cos ( δ ) ) - Rroll 24 π … and: R roll 3 =(κ 31 +κ 32 *sign(δ*γ))*(1−cos(|γ|))
1 - 10 . (canceled)
11 : A method for producing a motor vehicle tire, the method comprising:
estimating an effective rolling radius R roll of the tire by using a formula having a form of:
R roll= R roll 1 +R roll 2 +R roll 3 ,
where:
Rroll
1
=
Rroll
11
-
[
(
κ
11
+
κ
12
*
deflect
Pg
)
]
*
(
1
-
exp
(
-
deflect
Pg
*
Rroll
16
)
)
,
κ 11 =R roll 12 +R roll 13 *V
with:
κ 12 =R roll 14 +R roll 15 *V ,
Rroll
2
=
(
Rroll
21
+
Rroll
22
*
sign
(
δ
)
*
V
)
*
1
Fz
Rroll
23
*
(
1
-
cos
(
δ
)
)
-
Rroll
24
π
…
*
(
1
-
exp
(
-
Fz
Rroll
25
)
)
*
1
V
Rroll
26
…
*
[
arc
tan
(
Rroll
27
*
δ
-
Rroll
28
*
exp
(
-
Fz
Rroll
29
)
*
1
V
Rroll
30
)
+
π
2
]
,
and:
R roll 3 =(κ 31 +κ 32 *sign(δ*γ))*(1−cos(|γ|)),
with:
κ
31
=
Rroll
33
+
Rroll
34
*
(
1
-
exp
(
-
Fz
Rroll
35
)
)
κ
32
=
Rroll
36
+
Rroll
37
*
Fz
,
where parameters Rroll ij are numerical values, V is a speed of the vehicle, deflect is a deflection of the tire, Pg is an inflation pressure of the tire, F Z is a vertical load on the tire, δ is a cornering angle, and γ is a camber angle of the vehicle.
12 : The method according to claim 11 , wherein the deflection of the tire is determined by a formula having a form of:
deflect
=
F
Z
K
ZZ
+
(
R
eY
1
p
+
R
eY
2
)
·
F
Y
-
R
e
γ
.
γ
,
where:
K ZZ is a vertical stiffness of the tire, with K ZZp being a pneumatic component of the tire, with K ZZ0 being a structural component of the tire, and with K ZZ having a form of:
K ZZ =K ZZ0 +K ZZp ×Pg,
F Y is a transverse thrust force exerted on the tire,
γ is the camber angle of the vehicle,
R eγ is a coefficient of influence of the camber angle of the vehicle on the deflection of the tire,
p is the inflation pressure of the tire,
R eY1 is a coefficient that regulates a dependence of the deflection of the tire on the transverse thrust force F Y exerted the tire and on the inflation pressure p of the tire, and
R eY2 is a coefficient that regulates a dependence of the deflection of the tire on the transverse thrust force F Y exerted on the tire without an inflation pressure effect.
13 : The method according to claim 11 , wherein the parameters Rroll ij are numerical values defined by physical tests on a tire representative of the tire being produced.
14 : The method according to claim 13 , wherein the physical tests are carried out using a roller of a flat ground type.
15 : The method according to claim 11 , further comprising:
using software for simulating force dynamics at a wheel center.
16 : The method according to claim 15 , wherein the parameters Rroll ij are numerical values used in the software for simulating the force dynamics at the wheel center.
17 : A processor for determining a behaviour of a tire being produced for a motor vehicle, the processor being programmed to perform a method comprising:
estimating an effective rolling radius R roll of the tire by using a formula having a form of:
R roll= R roll 1 +R roll 2 +R roll 3 ,
where:
Rroll
1
=
Rroll
11
-
[
(
κ
11
+
κ
12
*
deflect
Pg
)
]
*
(
1
-
exp
(
-
deflect
Pg
*
Rroll
16
)
)
,
κ 11 =R roll 12 +R roll 13 *V
with:
κ 12 =R roll 14 +R roll 15 *V ,
Rroll
2
=
(
Rroll
21
+
Rroll
22
*
sign
(
δ
)
*
V
)
*
1
Fz
Rroll
23
*
(
1
-
cos
(
δ
)
)
-
Rroll
24
π
…
*
(
1
-
exp
(
-
Fz
Rroll
25
)
)
*
1
V
Rroll
26
…
*
[
arc
tan
(
Rroll
27
*
δ
-
Rroll
28
*
exp
(
-
Fz
Rroll
29
)
*
1
V
Rroll
30
)
+
π
2
]
,
and:
R roll 3 =(κ 31 +κ 32 *sign(δ*γ))*(1−cos(|γ|)),
with:
κ
31
=
Rroll
33
+
Rroll
34
*
(
1
-
exp
(
-
Fz
Rroll
35
)
)
κ
32
=
Rroll
36
+
Rroll
37
*
Fz
,
where parameters Rroll ij are numerical values, V is a speed of the vehicle, deflect is a deflection of the tire, Pg is an inflation pressure of the tire, F Z is a vertical load on the tire, δ is a cornering angle, and γ is a camber angle of the vehicle.
18 : The processor according to claim 17 , wherein the deflection of the tire is determined by a formula having a form of:
deflect
=
F
Z
K
ZZ
+
(
R
eY
1
p
+
R
eY
2
)
·
F
Y
-
R
e
γ
.
γ
,
where:
K ZZ is a vertical stiffness of the tire, with K ZZp being a pneumatic component of the tire, with K ZZ0 being a structural component of the tire, and with K ZZ having a form of:
K ZZ =K ZZ0 +K ZZp ×Pg,
F Y is a transverse thrust force exerted on the tire,
γ is the camber angle of the vehicle,
R eγ is a coefficient of influence of the camber angle of the vehicle on the deflection of the tire,
p is the inflation pressure of the tire,
R eY1 is a coefficient that regulates a dependence of the deflection of the tire on the transverse thrust force F Y exerted the tire and on the inflation pressure p of the tire, and
R eY2 is a coefficient that regulates a dependence of the deflection of the tire on the transverse thrust force F Y exerted on the tire without an inflation pressure effect.
19 : The processor according to claim 17 , wherein the parameters Rroll ij are numerical values defined by physical tests on a tire representative of the tire being produced.
20 : The processor according to claim 18 , wherein the parameters Rroll ij are numerical values defined by physical tests on a tire representative of the tire being produced.
21 : A tire for a motor vehicle tire, the tire being produced by a simulation method comprising:
estimating an effective rolling radius R roll of the tire by using a formula having a form of:
R roll= R roll 1 +R roll 2 +R roll 3 ,
where:
Rroll
1
=
Rroll
11
-
[
(
κ
11
+
κ
12
*
deflect
Pg
)
]
*
(
1
-
exp
(
-
deflect
Pg
*
Rroll
16
)
)
,
κ 11 =R roll 12 +R roll 13 *V
with:
κ 12 =R roll 14 +R roll 15 *V ,
Rroll
2
=
(
Rroll
21
+
Rroll
22
*
sign
(
δ
)
*
V
)
*
1
Fz
Rroll
23
*
(
1
-
cos
(
δ
)
)
-
Rroll
24
π
…
*
(
1
-
exp
(
-
Fz
Rroll
25
)
)
*
1
V
Rroll
26
…
*
[
arc
tan
(
Rroll
27
*
δ
-
Rroll
28
*
exp
(
-
Fz
Rroll
29
)
*
1
V
Rroll
30
)
+
π
2
]
,
and:
R roll 3 =(κ 31 +κ 32 *sign(δ*γ))*(1−cos(|γ|)),
with:
κ
31
=
Rroll
33
+
Rroll
34
*
(
1
-
exp
(
-
Fz
Rroll
35
)
)
κ
32
=
Rroll
36
+
Rroll
37
*
Fz
,
where parameters Rroll ij are numerical values, V is a speed of the vehicle, deflect is a deflection of the tire, Pg is an inflation pressure of the tire, F Z is a vertical load on the tire, δ is a cornering angle, and γ is a camber angle of the vehicle.