U.S. patent application number 16/637683 was filed with the patent office on 2020-06-25 for control apparatus for vehicle, control system for vehicle, and control method for vehicle.
The applicant listed for this patent is Hitachi Automotive Systems, Ltd.. Invention is credited to Satoshi KANEKO, Keisuke SUZUKI, Kazuya TAKAHASHI.
Application Number | 20200198475 16/637683 |
Document ID | / |
Family ID | 65271077 |
Filed Date | 2020-06-25 |
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United States Patent
Application |
20200198475 |
Kind Code |
A1 |
KANEKO; Satoshi ; et
al. |
June 25, 2020 |
Control Apparatus for Vehicle, Control System for Vehicle, and
Control Method for Vehicle
Abstract
A control apparatus for a vehicle includes an addition portion
that outputs a post-compensation driver request torque, which is
acquired by adding a driving torque (a loss compensation driving
torque) lost due to a braking torque provided to a wheel on a
low-.mu. road surface side according to a BLSD request hydraulic
pressure calculated by a BLSD request hydraulic pressure
calculation processing portion to a driver request torque
calculated by a driver request torque calculation processing
portion, to a motor.
Inventors: |
KANEKO; Satoshi;
(Hitachinaka-shi, Ibaraki, JP) ; SUZUKI; Keisuke;
(Hitachinaka-shi, Ibaraki, JP) ; TAKAHASHI; Kazuya;
(Sagamihara-shi, Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hitachi Automotive Systems, Ltd. |
Hitachinaka-shi, Ibaraki |
|
JP |
|
|
Family ID: |
65271077 |
Appl. No.: |
16/637683 |
Filed: |
July 11, 2018 |
PCT Filed: |
July 11, 2018 |
PCT NO: |
PCT/JP2018/026157 |
371 Date: |
February 7, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60W 2552/40 20200201;
B60W 10/18 20130101; B60L 2240/465 20130101; B60T 8/175 20130101;
B60W 10/04 20130101; B60W 10/08 20130101; B60L 3/108 20130101; B60W
10/184 20130101; B60L 15/20 20130101; B60W 2540/12 20130101; B60L
3/106 20130101; B60T 2210/12 20130101; B60L 2240/423 20130101; B60T
8/1764 20130101; B60T 2270/213 20130101; B60W 2710/18 20130101;
B60W 2710/083 20130101 |
International
Class: |
B60L 15/20 20060101
B60L015/20; B60W 10/08 20060101 B60W010/08; B60W 10/184 20060101
B60W010/184; B60T 8/175 20060101 B60T008/175 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 9, 2017 |
JP |
2017-153896 |
Claims
1. A control apparatus for a vehicle, comprising: a driving source
configured to provide a driving torque to a driving axle connecting
a first driving wheel and a second driving wheel of the vehicle to
each other; a brake apparatus capable of providing braking torques
to the first driving wheel and the second driving wheel
individually; a request driving torque calculation portion
configured to calculate a request driving torque of the vehicle
based on an accelerator operation; a frictional brake calculation
portion configured to calculate the braking torque to provide to
the first driving wheel by the brake apparatus on a split road
surface on which a frictional coefficient of a road surface where
the first driving wheel contacts a ground is lower than a
frictional coefficient of a road surface where the second driving
wheel contacts the ground; and a correction request driving torque
output portion configured to output a correction request driving
torque, which is acquired by adding a driving torque lost due to
the braking torque calculated by the frictional brake calculation
portion to the request driving torque calculated by the request
driving torque calculation portion, to the driving source.
2. The control apparatus for the vehicle according to claim 1,
further comprising a first limiter processing portion configured to
limit the correction request driving torque in such a manner that a
difference between the request driving torque calculated by the
request driving torque calculation portion and a driving torque of
the vehicle matches or falls below the driving torque lost due to
the braking torque calculated by the frictional brake calculation
portion.
3. The control apparatus for the vehicle according to claim 1,
wherein the driving source is a motor.
4. The control apparatus for the vehicle according to claim 3,
further comprising a slip control portion configured to prevent a
slip of the first driving wheel by controlling an output torque of
the motor, wherein the lost driving torque is a value acquired by
subtracting a difference between the driving torque generated due
to the control on the output torque of the motor by the slip
control portion and the driving torque lost due to the braking
torque calculated by the frictional brake calculation portion from
the request driving torque.
5. The control apparatus for the vehicle according to claim 1,
wherein the control apparatus for the vehicle reduces the
correction request driving torque to output to the driving source
by the correction request driving torque output portion toward the
request driving torque when reducing the braking torque to provide
to the first driving wheel by the brake apparatus toward zero.
6. The control apparatus for the vehicle according to claim 5,
wherein the control apparatus for the vehicle changes the braking
torque to provide to the first driving wheel by the brake apparatus
and the correction request driving torque to output to the driving
source by the correction request driving torque output portion in
phase with each other, when reducing the braking torque toward zero
and reducing the correction request driving torque toward the
request driving torque.
7. The control apparatus for the vehicle according to claim 1,
further comprising a second limiter processing portion configured
to limit the correction request driving torque based on a limit
value acquired by adding a difference between the request driving
torque calculated by the request driving torque calculation portion
and a value of a driving torque converted from a longitudinal
acceleration of the vehicle to the request driving torque
calculated by the request driving torque calculation portion.
8. A control apparatus for a vehicle, comprising: a driving source
configured to provide a driving torque to a driving axle connecting
a first driving wheel and a second driving wheel of the vehicle to
each other; and a brake apparatus capable of providing braking
torques to the first driving wheel and the second driving wheel
individually, wherein the control apparatus for the vehicle outputs
an instruction for generating a higher driving torque than a
request driving torque of the vehicle based on an accelerator
operation to the driving source with the braking torque provided to
the first driving wheel by the brake apparatus on a split road
surface on which a frictional coefficient of a road surface where
the first driving wheel contacts a ground is lower than a
frictional coefficient of a road surface where the second driving
wheel contacts the ground.
9. The control apparatus for the vehicle according to claim 8,
wherein the control apparatus for the vehicle outputs the driving
torque to the driving source by adding a driving torque lost due to
the braking torque provided to the first driving wheel by the brake
apparatus to the request driving torque.
10. The control apparatus for the vehicle according to claim 9,
wherein the control apparatus for the vehicle imposes a limit in
such a manner that a difference between the request driving torque
and a driving torque of the vehicle matches or falls below the lost
driving torque.
11. The control apparatus for the vehicle according to claim 8,
wherein the control apparatus for the vehicle reduces a higher
driving torque than the request driving torque toward the request
driving torque when reducing the braking torque provided to the
first driving wheel by the brake apparatus toward zero.
12. The control apparatus for the vehicle according to claim 8,
wherein the control apparatus for the vehicle limits the
instruction to output to the driving source based on a limit value
acquired by adding a difference between the request driving torque
and a value of a driving torque converted from a longitudinal
acceleration of the vehicle to the request driving torque.
13. A control system for a vehicle, comprising: a driving source
configured to provide a driving torque to a driving axle connecting
a first driving wheel and a second driving wheel of the vehicle to
each other; a brake apparatus capable of providing braking torques
to the first driving wheel and the second driving wheel
individually; and a control unit configured to control the driving
source and the brake apparatus, wherein the control unit outputs an
instruction for generating a driving torque exceeding a request
driving torque of the vehicle based on accelerator steering to the
driving source with the braking torque provided to the first
driving wheel by the brake apparatus on a split road surface on
which a frictional coefficient of a road surface where the first
driving wheel contacts a ground is lower than a frictional
coefficient of a road surface where the second driving wheel
contacts the ground.
14. The control system for the vehicle according to claim 13,
wherein the control unit limits the instruction to output to the
driving source in such a manner that a difference between the
request driving torque and a driving torque of the vehicle matches
or falls below a driving torque lost due to the braking torque
provided to the first driving wheel by the brake apparatus.
15. The control system for the vehicle according to claim 13,
wherein the driving source is a motor.
16. The control system for the vehicle according to claim 13,
wherein the control system for the vehicle reduces a higher driving
torque than the request driving torque toward the request driving
torque when reducing the braking torque provided to the first
driving wheel by the brake apparatus toward zero.
17. The control system for the vehicle according to claim 13,
wherein the control system for the vehicle limits the instruction
to output to the driving source based on a limit value acquired by
adding a difference between the request driving torque and a value
of a driving torque converted from a longitudinal acceleration of
the vehicle to the request driving torque.
18. A control method for a vehicle, comprising: the step of
calculating a request driving torque of the vehicle based on an
accelerator operation; the step of calculating a braking torque to
provide to the first driving wheel by a brake apparatus capable of
providing braking torques to the first driving wheel and the second
driving wheel individually on a split road surface on which a
frictional coefficient of a road surface where the first driving
wheel of the vehicle contacts a ground is lower than a frictional
coefficient of a road surface where the second driving wheel of the
vehicle contacts the ground, the second driving wheel being
connected to the first driving wheel via a driving axle; and the
step of outputting a correction request driving torque, which is
acquired by adding a driving torque lost due to the braking torque
calculated by the frictional brake calculation step to the request
driving torque calculated by the request driving torque calculation
step, to a driving source configured to provide a driving torque to
the driving axle, as a correction request driving torque
output.
19. The control method for the vehicle according to claim 18,
further comprising the step of limiting the correction request
driving torque in such a manner that a difference between the
request driving torque calculated by the request driving torque
calculation step and a driving torque of the vehicle matches or
falls below the driving torque lost due to the braking torque
calculated by the frictional brake calculation step.
20. The control method for the vehicle according to claim 18,
wherein the control method for the vehicle reduces the correction
request driving torque to output to the driving source by the
correction request driving torque output step toward the request
driving torque when reducing the braking torque to provide to the
first driving wheel by the brake apparatus toward zero.
21. The control method for the vehicle according to claim 18,
further comprising a second limiter processing step of limiting the
correction request driving torque based on a limit value acquired
by adding a difference between the request driving torque
calculated by the request driving torque calculation step and a
value of a driving torque converted from a longitudinal
acceleration of the vehicle to the request driving torque
calculated by the request driving torque calculation step.
Description
TECHNICAL FIELD
[0001] The present invention relates to a control apparatus for a
vehicle, a control system for a vehicle, and a control method for a
vehicle.
BACKGROUND ART
[0002] PTL 1 discloses a technique that, when a difference in a
target driving torque between left and right driving wheels matches
or exceeds a driver request torque according to an accelerator
operation amount on a split road surface, limits an upper limit
value on the difference in the target driving torque according to
the driver request torque.
CITATION LIST
Patent Literature
[0003] [PTL 1] Japanese Patent Application Public Disclosure No.
2008-295828
SUMMARY OF INVENTION
Technical Problem
[0004] However, the above-described patent literature, PTL 1 raises
such a problem that an output of a driving source that provides
driving torques to the driving wheels is limited according to the
driver request torque, which makes it impossible to acquire a
longitudinal acceleration of the vehicle that is requested by the
driver on the split road surface.
Solution to Problem
[0005] One of objects of the present invention is to provide a
control apparatus for a vehicle, a control system for a vehicle,
and a control method for a vehicle capable of preventing the
reduction in the longitudinal acceleration on the split road
surface.
[0006] According to one aspect of the present invention, a control
apparatus for a vehicle calculates a request driving torque of the
vehicle based on an accelerator operation, and outputs the request
driving torque after adding a driving torque lost due to a braking
torque provided to a first driving wheel by a brake apparatus
thereto on a split road surface on which a frictional coefficient
of a road surface where the first driving wheel contacts a ground
is lower than a frictional coefficient of a road surface where a
second driving wheel contacts the ground.
[0007] Therefore, according to the control apparatus for the
vehicle according to the one aspect of the present invention, it is
possible to prevent the reduction in the longitudinal acceleration
on the split road surface.
BRIEF DESCRIPTION OF DRAWINGS
[0008] FIG. 1 illustrates a control system of an electric vehicle
according to a first embodiment.
[0009] FIG. 2 is a control block diagram of a vehicle control
apparatus 12 according to the first embodiment.
[0010] FIG. 3 is a control block diagram of a loss compensation
driving torque calculation processing portion 12e.
[0011] FIG. 4 illustrates driving torques on front wheels in a case
where request driving torque correction control is not performed
when BLSD control is actuated on a split road surface.
[0012] FIG. 5 illustrates driving torques on the front wheels in a
case where the request driving torque correction control is
performed when the BLSD control is actuated on the split road
surface.
[0013] FIG. 6 is a timing chart in a case where the request driving
torque correction control according to the first embodiment is not
performed when the vehicle starts running on the split road
surface.
[0014] FIG. 7 is a timing chart in a case where the request driving
torque correction control according to the first embodiment is
performed when the vehicle starts running on the split road
surface.
[0015] FIG. 8 is a timing chart during a period from time t4 to
time t5 illustrated in FIG. 7.
[0016] FIG. 9 is a timing chart in a case where the request driving
torque correction control according to the first embodiment is
performed when the vehicle moves onto the split road surface after
starting running on a high-.mu. even road surface.
[0017] FIG. 10 is a control block diagram of a vehicle control
apparatus 12 according to a second embodiment.
[0018] FIG. 11 is a control block diagram of a loss compensation
driving torque limit processing portion 12f according to the second
embodiment.
[0019] FIG. 12 is a timing chart of request driving torque
correction control according to the second embodiment when the
vehicle starts running on the split road surface.
DESCRIPTION OF EMBODIMENTS
First Embodiment
[0020] FIG. 1 illustrates a control system of an electric vehicle
according to a first embodiment.
[0021] The electric vehicle according to the first embodiment
includes front wheels 1FL and 1FR working as driving wheels and
rear wheels 1RL and 1RR working as driven wheels, and includes an
electric motor (hereinafter referred to as a motor) 2 as a driving
source that provides driving torques to the front wheels 1FL and
1FR. Power is transmitted between the motor 2 and the front wheels
1FL and 1FR via a reducing gear 3, a differential gear 4, and
driving axles 5FL and 5FR. The wheels 1FL, 1FR, 1RL, and 1RR
include wheel speed sensors 6FL, 6FR, 6RL, and 6RR, which detect
wheel speeds, respectively. The motor 2 includes a resolver 7,
which detects a rotational speed of the motor. The vehicle includes
a low-voltage battery 8 and a high-voltage battery 9. The
low-voltage battery 8 is, for example, a lead storage battery. The
high-voltage battery 9 is, for example, a lithium ion battery or a
nickel hydrogen battery. The high-voltage battery 9 is charged by
electric power after a voltage of the electric power is increased
by a DC-DC converter 10. The wheels 1FL, 1FR, 1RL, and 1RR include
hydraulic brake units 11FL, 11FR, 11RL, and 11RR as brake
apparatuses, respectively. The brake units 11FL, 11FR, 11RL, and
11RR provide braking torques to the wheels 1FL, 1FR, 1RL, and 1RR
corresponding thereto according to supplied brake hydraulic
pressures (wheel cylinder hydraulic pressures), respectively.
[0022] The electric vehicle includes a vehicle control apparatus (a
control unit) 12, a motor control apparatus 13, a brake control
apparatus 14, and a battery control apparatus 15. These control
apparatuses 12, 13, 14, and 15 share information with one another
via a CAN bus 16. The vehicle control apparatus 12 inputs
information from various kinds of sensors and comprehensively
controls the vehicle. The vehicle control apparatus 12 calculates a
request driving torque of the vehicle according to a driver's
accelerator operation or the like, and calculates a request torque
that the motor 2 should output to realize the request driving
torque. Further, the vehicle control apparatus 12 calculates a
request braking force of the vehicle according to a driver's brake
operation or the like, and calculates a request hydraulic pressure
that should be supplied to each of the brake units 11FL, 11FR,
11RL, and 11RR for realizing the request braking force. The motor
control apparatus 13 controls electric power to supply to the motor
2 based on the request torque. The brake control apparatus 14
controls brake fluid to supply to each of the brake units 11FL,
11FR, 11RL, and 11RR based on the request hydraulic pressure. The
battery control apparatus 15 monitors a charging/discharging state
of the high-voltage battery 9 and a battery cell forming the
high-voltage battery 9. The battery control apparatus 15 calculates
a battery request torque limit value based on the
charging/discharging state of the high-voltage battery 9 or the
like. The battery request torque limit value is a maximum torque
allowed with respect to the motor 2. For example, when the charging
amount of the high-voltage battery 9 reduces, the battery request
torque limit value is set to a smaller value than normal.
[0023] The vehicle control apparatus 12 performs slip control of
preventing a driving slip by reducing the output torque of the
motor 2 when the driving slip has occurred on one of the front
wheels 1FL and 1FR, which are the driving wheels. The vehicle
control apparatus 12 calculates a slip control target wheel speed
using a difference between a wheel speed (a driving wheel speed)
and a vehicle speed as a threshold value. The vehicle speed is, for
example, assumed to be an average value of the wheel speeds of the
rear wheels 1RL and 1RR, which are the driven wheels. The vehicle
control apparatus 12 calculates a slip control torque for acquiring
the slip control target wheel speed, and outputs the slip control
torque to the motor control apparatus 13 as a request torque.
[0024] Further, when a difference is generated between the speeds
of the front wheels 1FL and 1FR while the vehicle is running on a
split road surface or the like, the vehicle control apparatus 12
performs brake LSD (BLSD) control of applying the braking force to
one of the front wheels 1FL and 1FR that rotates at a higher speed
(a slip wheel), and increasing the driving torque on the other of
them that rotates at a lower speed (a non-slip wheel). The split
road surface refers to a road surface on which a frictional
coefficient is different between left and right wheels. The
frictional coefficient refers to a ratio between a frictional force
working between a tire and a road surface where the tire contacts
the ground and a pressure vertically applied to the road surface
where the tire contacts the ground. The vehicle control apparatus
12 calculates a BLSD target wheel speed of the slip wheel for
reducing the difference between the rotational speeds of the front
wheels 1FL and 1FR to the threshold value or smaller, and
calculates a BLSD request hydraulic pressure of the slip wheel for
acquiring the BLSD target wheel speed. The vehicle control
apparatus 12 outputs the BLSD request hydraulic pressure to the
brake control apparatus 14 as a request hydraulic pressure.
[0025] Now, providing the braking torque to the slip wheel by the
BLSD control cancels out a part of the driving torque on the slip
wheel by this braking torque, thereby reducing the driving torque
on the vehicle to lower than the request driving torque. Therefore,
the longitudinal acceleration of the vehicle does not reach the
longitudinal acceleration requested by the driver, and therefore
the driver is forced to engage in an operation of additionally
pressing the accelerator pedal.
[0026] In the first embodiment, with the aim of preventing the
reduction in the longitudinal acceleration along with the BLSD
control on the split road surface, the vehicle control apparatus 12
performs request driving torque correction control of generating a
higher driving torque than the request driving torque in parallel
with the BLSD control. In the following description, details of the
request driving torque correction control will be described.
[0027] FIG. 2 is a control block diagram of the vehicle control
apparatus 12 according to the first embodiment.
[0028] A driver request torque calculation processing portion (a
request driving torque calculation portion) 12a calculates the
driver request torque (the request driving torque) by referring to
a map based on the accelerator operation amount and the vehicle
speed (a request driving torque calculation step).
[0029] A BLSD request hydraulic pressure calculation processing
portion (a frictional brake calculation portion) 12b calculates the
BLSD request hydraulic pressure for causing the wheel speed of the
slip wheel to match the BLSD target wheel speed based on the speed
of the driving wheel (the wheel speed of the slip wheel), the wheel
speed, and the BLSD target wheel speed (a frictional brake
calculation step).
[0030] An addition portion (a correction request driving torque
output portion) 12c calculates a post-compensation driver request
torque by adding a loss compensation driving torque (a correction
request driving torque), which will be described below, to the
driver request torque (a correction request driving torque output
step).
[0031] A slip control torque calculation processing portion (a slip
control portion) 12d calculates a slip control torque for causing
the driving torque of the vehicle to match the post-compensation
driver request torque while converging the wheel speeds of the
front wheels 1FL and 1FR to the slip control target wheel speed
based on the slip control target wheel speed, the vehicle speed,
the driving wheel speed, and the post-compensation driver request
torque.
[0032] A loss compensation driving torque calculation processing
portion 12e calculates the loss compensation driving torque based
on the BLSD request hydraulic pressure, the driver request torque,
and the slip control torque. FIG. 3 illustrates a control block
diagram of the loss compensation driving torque calculation
processing portion 12e.
[0033] A BLSD request hydraulic pressure-corresponding torque
calculation processing portion 17 calculates a BLSD request
hydraulic pressure-corresponding torque, which is a braking torque
converted from the BLSD request hydraulic pressure.
[0034] A multiplication portion 18 calculates a slip control torque
for one wheel (for the slip wheel) by dividing the slip control
torque in half.
[0035] A multiplication portion 19 calculates a driver request
torque for one wheel (for the slip wheel) by dividing the driver
request torque in half.
[0036] A comparison portion 20 subtracts the BLSD request hydraulic
pressure-corresponding torque from the slip control torque.
[0037] A comparison portion 21 subtracts an output of the
comparison portion 20 (the slip control torque--the BLSD request
hydraulic pressure-corresponding torque) from the driver request
torque.
[0038] A limit portion (a first limiter processing portion) 22 sets
a value selected by selecting the lower one of the outputs of the
BLSD request hydraulic pressure-corresponding torque and the
comparison portion 21 as the loss compensation driving torque
(first limiter processing step).
[0039] A multiplication portion 23 calculates a loss compensation
driving torque for the two wheels by doubling the loss compensation
driving torque.
[0040] Next, a general concept of the control of the correction of
the request driving torque according to the first embodiment will
be described based on a specific example thereof.
[0041] FIG. 4 illustrates the driving torques on front wheels in a
case where the request driving torque correction control is not
performed when the BLSD control is actuated on the split road
surface. Suppose that the split road surface is a low-.mu. road
surface on the front right wheel side and is a high-.mu. road
surface on the front left wheel side.
[0042] When the vehicle enters the split road surface and the BLSD
control is actuated, the braking torque is provided to the front
right wheel on the low-.mu. road surface side. Due to the BLSD
control, the driving torque on the front left wheel on the
high-.mu. road surface side recovers to 5, which is similar to on
the high-.mu. even road surface. However, the driving torque is
partially canceled out by the provision of the braking torque to
the front right wheel, and therefore the driving torque on the
front right wheel reduces to 3, which is a value acquired by
subtracting 2 corresponding to the loss due to the BLSD control
(the lost driving torque) from 5. Therefore, the driving torque on
the vehicle ends up 5+3=8 (a sum of the driving torques on the
front left and right wheels) while the driver request torque is 10,
thereby failing to achieve the longitudinal acceleration of the
vehicle according to the accelerator operation amount. Therefore,
the driver should additionally press the accelerator pedal to
compensate for the insufficiency of the longitudinal
acceleration.
[0043] FIG. 5 illustrates the driving torques on the front wheels
in a case where the request driving torque correction control is
performed when the BLSD control is actuated on the split road
surface. Suppose that the split road surface is the low-.mu. road
surface on the front right wheel side and is the high-.mu. road
surface on the front left wheel side.
[0044] In the request driving torque correction control, the motor
2 is controlled so as to generate the post-compensation driver
request torque 10+4=14, which is a value acquired by adding the
loss compensation driving torque 2.times.2=4 for compensating for
the lost driving torque of 2 due to the BLSD control to the driver
request torque of 10. As a result, although the driving torque is
kept at 3 on the front right wheel, on which a tire longitudinal
force is saturated, the driving torque increases from 5 to 5+2=7 on
the front left wheel, on which the tire longitudinal force is not
saturated, so that the driving torque on the vehicle recovers to
7+3=10. Therefore, the vehicle control apparatus 12 can achieve the
driving torque on the vehicle that matches the driver request
torque. As a result, the vehicle control apparatus 12 can realize
the acceleration of the vehicle that is desired by the driver
without forcing the driver to engage in the operation of
additionally pressing the accelerator pedal on the split road
surface.
[0045] FIG. 6 is a timing chart in a case where the request driving
torque correction control according to the first embodiment is not
performed when the vehicle starts running on the split road
surface. Suppose that the split road surface is the low-.mu. road
surface on the front right wheel side and is the high-.mu. road
surface on the front left wheel side.
[0046] At time t1, the slip control is started because an actual
wheel speed of the front right wheel exceeds the slip control
target wheel speed. The difference between the driver request
torque and the slip control torque starts increasing.
[0047] At time t2, the BLSD control is started because the
difference in the rotational speed between the front left and right
wheels exceeds the BLSD target wheel speed. Because the BLSD
request hydraulic pressure rises and the braking torque is provided
to the front right wheel, the actual wheel speed of the front right
wheel is converged to the slip control target wheel speed, and the
slip control torque increases toward the driver request torque.
[0048] At time t3, the slip control torque reaches the driver
request torque, but the driving torque on the front right wheel
reduces by an amount corresponding to the loss due to the BLSD
control, so that the longitudinal acceleration of the vehicle is
kept at an acceleration that would be reached when the BLSD control
is still in progress, which is lower than the acceleration
corresponding to the driver request torque according to the
accelerator operation amount, failing to realize the longitudinal
acceleration according to the accelerator operation amount.
[0049] At time t4, the vehicle exits the split road surface and
enters the high-.mu. even road surface, and therefore the BLSD
request hydraulic pressure starts reducing. The longitudinal
acceleration of the vehicle starts increasing toward the
acceleration corresponding to the driver request torque.
[0050] FIG. 7 is a timing chart in a case where the request driving
torque correction control according to the first embodiment is
performed when the vehicle starts running on the split road
surface. Suppose that the split road surface is the low-.mu. road
surface on the front right wheel side and is the high-.mu. road
surface on the front left wheel side.
[0051] The timing chart exhibits the same content as in FIG. 6
during a period since time t1 to time t2.
[0052] At time t2, the request driving torque correction control is
started at the same time as the start of the BLSD control. In the
request driving torque correction control, the driving torque
canceled out due to the BLSD control on the wheel on the low-.mu.
road surface side (the front right wheel) is compensated for by the
driving torque on the wheel on the high-.mu. road surface side (the
front left wheel), so that the post-compensation driver request
torque is calculated by adding the driving torque corresponding to
the driving torque canceled out on the front right wheel (the loss
compensation driving torque) to the driver request torque
determined based on an accelerator position after the BLSD control
is started. The post-compensation driver request torque increases
until the sum of the driving torques on the front left and right
wheels reaches the driver request torque. The slip control torque
is calculated based on the post-compensation driver request
torque.
[0053] At time t3, the slip control torque exceeds the driver
request torque, but does not reach the post-compensation driver
request torque. Therefore, the slip control torque further
continues increasing. After the slip control torque reaches the
post-compensation driver request torque, the longitudinal
acceleration of the vehicle reaches the acceleration corresponding
to the driver request torque according to the accelerator operation
amount.
[0054] At time t4, the vehicle exits the split road surface and
enters the high-.mu. even road surface, and therefore the BLSD
request hydraulic pressure gradually reduces. According thereto,
the post-compensation driver request torque and the slip control
torque reduce.
[0055] At time t5, the BLSD request hydraulic pressure reaches zero
and the slip control torque matches the driver request torque, so
that the vehicle returns to the same state as the running state on
the high-.mu. even road surface.
[0056] Next, a method for reducing the BLSD request hydraulic
pressure and the post-compensation driver request torque in a
period from time t4 to time t5 will be described. FIG. 8 is a
timing chart during a period from time t4 to time t5 illustrated in
FIG. 7.
[0057] When the speed difference between the front wheels 1FL and
1FR is converged and the BLSD control is ended due to the movement
from the split road surface to the high-.mu. even road surface, the
vehicle control apparatus 12 reduces the BLSD request hydraulic
pressure and the post-compensation driver request torque at such a
gradient that the longitudinal acceleration of the vehicle hardly
changes and a vibration is hardly generated on the driving system.
At time t4, the wheel speed of the front right wheel considerably
falls below the BLSD target wheel speed due to the entry into the
high-.mu. road surface. Then, when the BLSD control is determined
to be turned off, the BLSD request hydraulic pressure reduces based
on the BLSD control, but the vehicle control apparatus 12 still
reduces the post-compensation driver request torque to the driver
request torque in the request driving torque correction control. At
this time, the vehicle control apparatus 12 reduces the loss
compensation driving torque in such a manner that a reduced amount
of the post-compensation driver request torque is kept in phase
with a reduced amount of the lost torque generated according to the
BLSD request hydraulic pressure (the lost torque due to the BLSD
control). The vehicle control apparatus 12 can reduce a change
amount of the acceleration by reducing the post-compensation driver
request torque and the BLSD request hydraulic pressure in phase
with each other. However, the reduced amounts do not have to be
equal to each other. The BLSD request hydraulic pressure
calculation processing portion 12b reduces the BLSD request
hydraulic pressure at a predetermined gradient when the wheel speed
of the slip wheel considerably falls below the BLSD target wheel
speed. The loss compensation driving torque calculation processing
portion 12e reduces the loss compensation driving torque at a
predetermined gradient according to the reduction in the BLSD
request hydraulic pressure. As a result, the vehicle control
apparatus 12 can control the reduced amount of the
post-compensation driver request torque according to the reduced
amount of the BLSD request hydraulic pressure. Alternatively, the
reduced amount of the BLSD request hydraulic pressure may be
controlled according to the reduced amount of the post-compensation
driver request torque.
[0058] FIG. 9 is a timing chart in a case where the request driving
torque correction control according to the first embodiment is
performed when the vehicle moves onto the split road surface after
starting running on the high-.mu. even road surface. Suppose that
the split road surface is the low-.mu. road surface on the front
right wheel side and is the high-.mu. road surface on the front
left wheel side.
[0059] At time t1, the driver starts the accelerator operation and
the driver request torque rises, so that the wheel speed of the
front right wheel increases and the longitudinal acceleration of
the vehicle reaches the acceleration corresponding to the driver
request torque.
[0060] At time t2, the vehicle exits the high-.mu. even road
surface and enters the slip road surface, thereby triggering a
start of the slip control.
[0061] At time t3, the request driving torque correction control is
started at the same time as the start of the BLSD control, so that
the post-compensation driver request torque is set to the value
acquired by adding the loss compensation driving torque to the
driver request torque. As a result, the vehicle control apparatus
12 can keep the longitudinal acceleration of the vehicle at the
acceleration corresponding to the driver request torque even when
the vehicle moves from the high-.mu. even road surface to the split
road surface.
[0062] The first embodiment brings about the following advantageous
effects. [0063] (1) The vehicle control apparatus 12 includes the
addition portion 12c that outputs the post-compensation driver
request torque, which is acquired by adding the driving torque (the
loss compensation driving torque) lost due to the braking torque
provided to the wheel on the low-.mu. road surface side according
to the BLSD request hydraulic pressure calculated by the BLSD
request hydraulic pressure calculation processing portion 12b to
the driver request torque calculated by the driver request torque
calculation processing portion 12a, to the motor 2.
[0064] As a result, the vehicle control apparatus 12 can prevent
the reduction in the longitudinal acceleration on the split road
surface. [0065] (2) The vehicle control apparatus 12 includes the
limit portion 22 that limits the post-compensation driver request
torque in such a manner that the difference between the driver
request torque and the driving torque of the vehicle (the slip
control torque--the BLSD request hydraulic pressure-corresponding
torque) matches or falls below the driving torque lost due to the
braking torque provided to the wheel on the low-.mu. road surface
side according to the BLSD request hydraulic pressure.
[0066] Now, hypothetically supposing that the post-compensation
driver request torque is not limited by the limit portion 22, this
configuration would lead to application of the frictional brake to
the wheel on the low-.mu. road surface side against the
post-compensation driver request torque and thus a further addition
of the driving torque to compensate for insufficiency corresponding
to this loss, thereby ending up in a repetition of the torque
addition. Therefore, the vehicle control apparatus 12 can prevent
the post-compensation driver request torque from continuing
increasing when the output driving torque exceeds the driving
torque corresponding to the accelerator operation amount, by
limiting the post-compensation driver request torque by the limit
portion 22. [0067] (3) The driving source is the motor 2.
[0068] As a result, the vehicle control apparatus 12 can improve
responsiveness when converging the driving torque from the
post-compensation driver request torque to the driver request
torque, when the vehicle moves from the split road surface to the
high-.mu. even road surface while being running at a constant
acceleration, compared to when the vehicle is an engine vehicle.
[0069] (4) The driving torque lost due to the braking torque
provided to the wheel on the low-.mu. road surface side according
to the BLSD request hydraulic pressure is the value acquired by
subtracting the difference between the slip control torque
calculated by the slip control torque calculation processing
portion 12d and the BLSD request hydraulic pressure-corresponding
torque calculated by the BLSD request hydraulic
pressure-corresponding torque calculation processing portion 17
from the driver request torque.
[0070] As a result, the vehicle control apparatus 12 can compensate
for the driving torque that is lost due to the frictional brake in
consideration of the slip control torque of the slip control.
[0071] (5) When reducing the braking torque according to the BLSD
request hydraulic pressure toward zero at the time of the end of
the BLSD control, the vehicle control apparatus 12 reduces the
post-compensation driver request torque toward the driver request
torque.
[0072] As a result, the vehicle control apparatus 12 can converge
the driving torque from the post-compensation driver request torque
to the driver request torque quickly at the same time as the exit
from the split road surface and the start of the reduction in the
frictional brake. In other words, the vehicle control apparatus 12
can prevent the longitudinal acceleration from changing between
before and after the split road surface. [0073] (6) The vehicle
control apparatus 12 causes the braking torque and the
post-compensation driver request torque to change in phase with
each other when reducing the braking torque according to the BLSD
request hydraulic pressure toward zero and reducing the
post-compensation driver request torque toward the driver request
torque at the time of the end of the BLSD control.
[0074] As a result, the vehicle control apparatus 12 can prevent
the change in the longitudinal acceleration and the vibration of
the driving system when the vehicle moves from the split road
surface to the high-.mu. even road surface. [0075] (7) The vehicle
control apparatus 12 outputs the instruction for generating the
higher driving torque than the driver request torque based on the
accelerator operation to the motor 2 with the braking torque
provided to the wheel on the low-.mu. road surface side due to the
BLSD control on the split road surface.
[0076] As a result, the vehicle control apparatus 12 can prevent
the reduction in the longitudinal acceleration on the split road
surface.
Second Embodiment
[0077] A second embodiment has a basic configuration similar to the
first embodiment, and therefore will be described focusing on only
differences from the first embodiment.
[0078] FIG. 10 is a control block diagram of a vehicle control
apparatus 12 according to the second embodiment.
[0079] An addition portion 12c calculates a pre-limit
post-compensation driver request torque by adding the loss
compensation driving torque to the driver request torque.
[0080] A loss compensation driving torque limit processing portion
12f calculates a post-limit post-compensation driver request torque
based on the driver request torque, the longitudinal acceleration
of the vehicle, and the pre-limit post-compensation driver request
torque. A value detected by the longitudinal acceleration sensor is
used as the longitudinal acceleration. FIG. 11 illustrates a
control block diagram of the loss compensation driving torque limit
processing portion 12f.
[0081] A longitudinal acceleration-corresponding driving torque
calculation processing portion 24 calculates a longitudinal
acceleration-corresponding driving torque, which is a driving
torque converted from the longitudinal acceleration.
[0082] A comparison portion 25 calculates an insufficient
acceleration-corresponding driving torque by reducing the
longitudinal acceleration-corresponding driving torque from the
driver request torque.
[0083] A comparison portion 26 calculates a post-compensation
driver request torque limit value by adding the insufficient
acceleration-corresponding driving torque to the pre-limit
post-compensation driver request torque.
[0084] A limit portion (a second limiter processing portion) 27
sets a value selected by selecting the lower one of the
post-compensation driver request torque and the post-compensation
driver request torque limit value as the post-limit
post-compensation driver request torque (second limiter processing
step).
[0085] The slip control torque calculation processing portion 12d
calculates the slip control torque for causing the wheel speeds of
the front wheels 1FL and 1FR to match the slip control target wheel
speed based on the slip control target wheel speed, the vehicle
speed, the driving wheel speed, and the post-limit
post-compensation driver request torque.
[0086] When attempting to control the slip of the wheel on the
low-.mu. road surface side by the BLSD control while running on the
split road surface, the vehicle experiences such a phenomenon that
the braking torque requested by the BLSD control cannot be acquired
due to insufficiency of the actual hydraulic pressure for the BLSD
request hydraulic pressure, insufficiency of the braking torque for
the actual hydraulic pressure, or the like. At this time, when the
output torque of the motor 2 is controlled so as to compensate for
the lost driving torque due to the BLSD control by the request
driving torque correction control, a driving torque exceeding the
driver request may be generated because the driving torque is
compensated for more than the actual lost driving torque. This
leads to generation of a longitudinal acceleration higher than
expected by the driver depending on the road surface condition on
the split road surface where the high-.mu. road surface and the
low-.mu. road surface are mixed, and therefore some measures should
be taken against it.
[0087] In the second embodiment, an upper limit on the
post-compensation driver request torque is limited by the
post-compensation driver request torque limit value. The
post-compensation driver request torque limit value is calculated
by adding the post-compensation driver request torque to the
driving torque corresponding to the insufficient acceleration
acquired by subtracting the longitudinal acceleration-corresponding
driving torque from the driver request torque. The longitudinal
acceleration-corresponding driving torque is the actual driving
force of the vehicle, and therefore the vehicle control apparatus
12 can prevent the generation of the longitudinal acceleration
exceeding the driver request by setting the upper limit on the
post-compensation driver request torque to the post-compensation
driver request torque limit value.
[0088] FIG. 12 is a timing chart of request driving torque
correction control according to the second embodiment when the
vehicle starts running on the split road surface. Suppose that the
split road surface is the low-.mu. road surface on the front right
wheel side and is the high-.mu. road surface on the front left
wheel side.
[0089] The timing chart exhibits the same content as in FIG. 6
during a period since time t1 to time t3, but the post-compensation
driver request torque limit value for limiting the upper limit on
the post-compensation driver request torque is set in the second
embodiment. The post-compensation driver request torque limit value
is calculated by adding the driving torque corresponding to the
insufficient longitudinal acceleration, which is the difference
between the driver request torque and the longitudinal
acceleration-corresponding driving torque, to the post-compensation
driver request torque.
[0090] At time t3, the actual brake hydraulic pressure starts
failing to keep up with the BLSD request hydraulic pressure. At
this time, if the post-compensation driver request torque limit
value is not set, the post-compensation driver request torque would
exceed the actual lost torque due to the BLSD control, and
therefore the set slip control torque would exceed the driver
request. As a result, the actual longitudinal acceleration would
exceed the acceleration corresponding to the driver request torque,
and therefore the generated longitudinal acceleration would exceed
the driver request.
[0091] On the other hand, in the second embodiment, the upper limit
on the post-compensation driver request torque is limited by the
post-compensation driver request torque limit value, so that the
increase in the post-compensation driver request torque is
restricted (prohibited) when the driving torque corresponding to
the insufficient longitudinal acceleration disappears. As a result,
the vehicle control apparatus 12 can prevent the occurrence of the
longitudinal acceleration exceeding the driver request.
[0092] The second embodiment brings about the following
advantageous effects. [0093] (8 ) The vehicle control apparatus 12
includes the limit portion 27 that limits the post-compensation
driver request torque based on the post-compensation driver request
torque limit value, which is acquired by adding the difference
between the driver request torque calculated by the driver request
torque calculation processing portion 12a and the longitudinal
acceleration-corresponding driving torque (the value of the driving
torque converted from the longitudinal acceleration of the vehicle)
calculated by the longitudinal acceleration-corresponding driving
torque calculation processing portion 24, to the driver request
torque.
[0094] As a result, the vehicle control apparatus 12 can prevent
the occurrence of the longitudinal acceleration exceeding the
driver request.
[Other Embodiments]
[0095] Having described the embodiments for implementing the
present invention, the specific configuration of the present
invention is not limited to the configurations of the embodiments,
and the present invention also includes a design modification and
the like thereof made within a range that does not depart from the
spirit of the present invention.
[0096] The driving source may be an engine, or a combination of an
engine and an electric motor. In other words, the present invention
can also be applied to an engine vehicle and a hybrid vehicle.
[0097] Next, a method for determining whether the constituent
features (the technical scope) of the present invention are
satisfied based on a vehicle behavior will be described (this
method can be restated as a method for discovering infringement of
the right of the present invention).
[0098] First, a vehicle equipped with a control apparatus deemed to
satisfy the constituent features (the technical scope) of the
present invention (infringe the right) is prepared. The control
apparatus is a control apparatus capable of performing so-called
LSD control, which performs differential control of the left and
right driving wheel by the brake.
[0099] The above-described vehicle is driven to run at a constant
acceleration on a test course in which the split road surface and
the high-.mu. even road surface are set. At this time, if the
longitudinal acceleration hardly changes (strictly speaking, the
longitudinal acceleration slightly changes for only a moment) when
the vehicle moves from the split road surface to the high-.mu. even
road surface with the brake LSD control actuated, it is apparent
that the output driving torque is higher than the driver request
torque based on the acceleration operation, and therefore this
control apparatus can be determined to satisfy the constituent
features of the present invention. The conventional control
apparatus performs control so as not to exceed the driver request
torque during the BLSD control, and therefore leads to a
considerable change in the longitudinal acceleration when the
vehicle exits the split road surface.
[0100] In the following description, technical ideas recognizable
from the above-described embodiments will be described.
[0101] A control apparatus for a vehicle, in one configuration
thereof, includes a driving source configured to provide a driving
torque to a driving axle connecting a first driving wheel and a
second driving wheel of the vehicle to each other, a brake
apparatus capable of providing braking torques to the first driving
wheel and the second driving wheel individually, a request driving
torque calculation portion configured to calculate a request
driving torque of the vehicle based on an accelerator operation, a
frictional brake calculation portion configured to calculate the
braking torque to provide to the first driving wheel by the brake
apparatus on a split road surface on which a frictional coefficient
of a road surface where the first driving wheel contacts a ground
is lower than a frictional coefficient of a road surface where the
second driving wheel contacts the ground, and a correction request
driving torque output portion configured to output a correction
request driving torque, which is acquired by adding a driving
torque lost due to the braking torque calculated by the frictional
brake calculation portion to the request driving torque calculated
by the request driving torque calculation portion, to the driving
source.
[0102] According to a further preferable configuration, the
above-described configuration further includes a first limiter
processing portion configured to limit the correction request
driving torque in such a manner that a difference between the
request driving torque calculated by the request driving torque
calculation portion and a driving torque of the vehicle matches or
falls below the driving torque lost due to the braking torque
calculated by the frictional brake calculation portion.
[0103] According to another preferable configuration, in any of the
above-described configurations, the driving source is a motor.
[0104] According to further another preferable configuration, any
of the above-described configurations further includes a slip
control portion configured to prevent a slip of the first driving
wheel by controlling an output torque of the motor. The lost
driving torque is a value acquired by subtracting a difference
between the driving torque generated due to the control on the
output torque of the motor by the slip control portion and the
driving torque lost due to the braking torque calculated by the
frictional brake calculation portion from the request driving
torque.
[0105] According to further another preferable configuration, in
any of the above-described configurations, the control apparatus
for the vehicle reduces the correction request driving torque to
output to the driving source by the correction request driving
torque output portion toward the request driving torque when
reducing the braking torque to provide to the first driving wheel
by the brake apparatus toward zero.
[0106] According to further another preferable configuration, in
any of the above-described configurations, the control apparatus
for the vehicle changes the braking torque to provide to the first
driving wheel by the brake apparatus and the correction request
driving torque to output to the driving source by the correction
request driving torque output portion in phase with each other,
when reducing the braking torque toward zero and reducing the
correction request driving torque toward the request driving
torque.
[0107] According to further another preferable configuration, any
of the above-described configurations further includes a second
limiter processing portion configured to limit the correction
request driving torque based on a limit value acquired by adding a
difference between the request driving torque calculated by the
request driving torque calculation portion and a value of a driving
torque converted from a longitudinal acceleration of the vehicle to
the request driving torque calculated by the request driving torque
calculation portion.
[0108] Further, from another aspect, a control apparatus for a
vehicle, in one configuration thereof, includes a driving source
configured to provide a driving torque to a driving axle connecting
a first driving wheel and a second driving wheel of the vehicle to
each other, and a brake apparatus capable of providing braking
torques to the first driving wheel and the second driving wheel
individually. The control apparatus for the vehicle outputs an
instruction for generating a higher driving torque than a request
driving torque of the vehicle based on an accelerator operation to
the driving source with the braking torque provided to the first
driving wheel by the brake apparatus on a split road surface on
which a frictional coefficient of a road surface where the first
driving wheel contacts a ground is lower than a frictional
coefficient of a road surface where the second driving wheel
contacts the ground.
[0109] Preferably, in the above-described configuration, the
control apparatus for the vehicle outputs the driving torque to the
driving source by adding a driving torque lost due to the braking
torque provided to the first driving wheel by the brake apparatus
to the request driving torque.
[0110] According to another preferable configuration, in any of the
above-described configurations, the control apparatus for the
vehicle imposes a limit in such a manner that a difference between
the request driving torque and a driving torque of the vehicle
matches or falls below the lost driving torque.
[0111] According to further another preferable configuration, in
any of the above-described configurations, the control apparatus
for the vehicle reduces a higher driving torque than the request
driving torque toward the request driving torque when reducing the
braking torque provided to the first driving wheel by the brake
apparatus toward zero.
[0112] According to further another preferable configuration, in
any of the above-described configurations, the control apparatus
for the vehicle limits the instruction to output to the driving
source based on a limit value acquired by adding a difference
between the request driving torque and a value of a driving torque
converted from a longitudinal acceleration of the vehicle to the
request driving torque.
[0113] Further, from another aspect, a control system for a
vehicle, in one configuration thereof, includes a driving source
configured to provide a driving torque to a driving axle connecting
a first driving wheel and a second driving wheel of the vehicle to
each other, a brake apparatus capable of providing braking torques
to the first driving wheel and the second driving wheel
individually, and a control unit configured to control the driving
source and the brake apparatus. The control unit outputs an
instruction for generating a driving torque exceeding a request
driving torque of the vehicle based on accelerator steering to the
driving source with the braking torque provided to the first
driving wheel by the brake apparatus on a split road surface on
which a frictional coefficient of a road surface where the first
driving wheel contacts a ground is lower than a frictional
coefficient of a road surface where the second driving wheel
contacts the ground.
[0114] Preferably, in the above-described configuration, the
control unit limits the instruction to output to the driving source
in such a manner that a difference between the request driving
torque and a driving torque of the vehicle matches or falls below a
driving torque lost due to the braking torque provided to the first
driving wheel by the brake apparatus.
[0115] According to another preferable configuration, in any of the
above-described configurations, the driving source is a motor.
[0116] According to further another preferable configuration, in
any of the above-described configurations, the control system for
the vehicle reduces a higher driving torque than the request
driving torque toward the request driving torque when reducing the
braking torque provided to the first driving wheel by the brake
apparatus toward zero.
[0117] According to further another preferable configuration, in
any of the above-described configurations, the control system for
the vehicle limits the instruction to output to the driving source
based on a limit value acquired by adding a difference between the
request driving torque and a value of a driving torque converted
from a longitudinal acceleration of the vehicle to the request
driving torque.
[0118] Further, from another aspect, a control method for a
vehicle, in one configuration thereof, includes the step of
calculating a request driving torque of the vehicle based on an
accelerator operation, the step of calculating a braking torque to
provide to the first driving wheel by a brake apparatus capable of
providing braking torques to the first driving wheel and the second
driving wheel individually on a split road surface on which a
frictional coefficient of a road surface where the first driving
wheel of the vehicle contacts a ground is lower than a frictional
coefficient of a road surface where the second driving wheel of the
vehicle connected to the first driving wheel via a driving axle
contacts the ground, and the step of outputting a correction
request driving torque, which is acquired by adding a driving
torque lost due to the braking torque calculated by the frictional
brake calculation step to the request driving torque calculated by
the request driving torque calculation step, to a driving source
configured to provide a driving torque to the driving axle as a
correction request driving torque output.
[0119] Preferably, the above-described configuration further
includes the step of limiting the correction request driving torque
in such a manner that a difference between the request driving
torque calculated by the request driving torque calculation step
and a driving torque of the vehicle matches or falls below the
driving torque lost due to the braking torque calculated by the
frictional brake calculation step.
[0120] According to another preferable configuration, in any of the
above-described configurations, the control method for the vehicle
reduces the correction request driving torque to output to the
driving source by the correction request driving torque output step
toward the request driving torque when reducing the braking torque
to provide to the first driving wheel by the brake apparatus toward
zero.
[0121] According to further another preferable configuration, any
of the above-described configurations further includes a second
limiter processing step of limiting the correction request driving
torque based on a limit value acquired by adding a difference
between the request driving torque calculated by the request
driving torque calculation step and a value of a driving torque
converted from a longitudinal acceleration of the vehicle to the
request driving torque calculated by the request driving torque
calculation step.
[0122] The present invention is not limited to the above-described
embodiments, and includes various modifications. For example, the
above-described embodiments have been described in detail to
facilitate better understanding of the present invention, and the
present invention shall not necessarily be limited to the
configurations including all of the described features. Further, a
part of the configuration of some embodiment can be replaced with
the configuration of another embodiment. Further, some embodiment
can also be implemented with a configuration of another embodiment
added to the configuration of this embodiment. Further, each of the
embodiments can also be implemented with another configuration
added, deleted, or replaced with respect to a part of the
configuration of this embodiment.
[0123] The present application claims priority under the Paris
Convention to Japanese Patent Application No. 2017-153896 filed on
Aug. 9, 2017. The entire disclosure of Japanese Patent Application
No. 2017-153896 filed on Aug. 9, 2017 including the specification,
the claims, the drawings, and the abstract is incorporated herein
by reference in its entirety.
REFERENCE SIGN LIST
[0124] 1FL, 1FR front wheel [0125] 1RL, 1RR rear wheel [0126] 2
motor (driving source) [0127] 5FL, 5FR driving axle [0128] 11FL,
11FR, 11RL, 11RR brake unit (brake apparatus) [0129] 12 vehicle
control apparatus (control unit) [0130] 12a driver request torque
calculation processing portion (request driving torque calculation
portion) [0131] 12b BLSD request hydraulic pressure calculation
processing portion (frictional brake calculation portion) [0132]
12c addition portion (correction request driving torque output
portion) [0133] 12d slip control torque calculation processing
portion (slip control portion) [0134] 22 limit portion (first
limiter processing portion) [0135] 27 limit portion (second limiter
processing portion)
* * * * *