Driving force control apparatus for a four-wheel drive vehicle

Patent metadata

Field	Value
Publication number	US-9527510-B2
Application number	US-201615143740-A
Country	US
Kind code	B2
Filing date	May 2, 2016
Priority date	May 13, 2015
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

Provided is a driving force control apparatus ( 10 ) configured to control driving forces applied to four wheels by controlling a driving force application apparatus (in-wheel motors ( 16 FL to 16 RR) and friction braking apparatus ( 24 )) configured to apply driving forces to front left and right wheels ( 12 FL and 12 FR) and rear left and right wheels ( 12 RL and 12 RR) independently. The driving force control apparatus ( 10 ) is configured to: calculate vehicle body speeds V j at positions of the four wheels, vertical loads Fz j of the four wheels, and a driving force Fx required by a driver (S 30 to S 50 ); calculate, based on those values, target driving forces F xj for the four wheels to set tire sliding vectors of the four wheels to be the same (S 60 ); and control the driving force application apparatus such that the driving forces of the four wheels are equal to corresponding target driving forces, respectively (S 70 ).

First claim

What is claimed is:

1. A driving force control apparatus, which is to be applied to a four-wheel drive vehicle comprising front left and right wheels and rear left and right wheels each having a tire and comprising a driving force application apparatus configured to apply driving forces to the four wheels independently of one another, and which is configured to control the driving forces to be applied to the four wheels by controlling the driving force application apparatus, the driving force control apparatus comprising:
an apparatus configured to acquire information on vehicle body speeds at positions of the four wheels;
an apparatus configured to acquire information on vertical loads of the four wheels; and
an apparatus configured to acquire information on a driving force required by a driver to the four-wheel drive vehicle,
wherein the driving force control apparatus is configured to calculate target driving forces for the four wheels required to set tire sliding vectors of the four wheels to be the same as one another based on the vehicle body speeds at the positions of the four wheels, the vertical loads of the four wheels, and the driving force required by the driver, and to control the driving force application apparatus such that the driving forces of the four wheels are equal to the corresponding target driving forces, respectively.

2. A driving force control apparatus according to claim 1 , wherein the driving force control apparatus is configured to calculate the target driving forces for the four wheels by distributing the driving force required by the driver to the four wheels such that each of the target driving forces for the four wheels is proportional to a ratio of a vertical load of a corresponding wheel to a vehicle body speed at a position of the corresponding wheel and a sum of the target driving forces for the four wheels is equal to the driving force required by the driver.

3. A driving force control apparatus according to claim 1 , wherein the driving force control apparatus is configured to calculate the target driving forces F x1 , F x2 , F x3 , and F x4 for the front left and right wheels and the rear left and right wheels in accordance with the following expression:

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F

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1

F

x
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2

F

x
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3

F

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4

]

=

1

∑

j
=
1

4

⁢

F

z
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⁢
j

V
j

⁡

[

F

z
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1

V
1

F

z
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2

V
2

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3

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3

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4

V
4

]

Assignees

• Toyota Motor Co Ltd

Inventors

• Katsuyama Etsuo
• Kobayashi Takao
• Sugiura Hideki

Classifications

• B60L2240/22

  Yaw angle · CPC title

• B60W2720/406

  between left and right wheel · CPC title

• B60L2240/461

  Speed · CPC title

• B60L15/2009 Primary

  for braking · CPC title

• Y02T10/72

  Electric energy management in electromobility · CPC title