JP5083025B2 - Vehicle braking / driving force control device - Google Patents

Description

  The present invention relates to a braking / driving force control device for a vehicle, and more particularly to a braking / driving force control device for a vehicle having stable steering performance.

As a vehicle braking / driving force control device, a yaw motion control device that distributes driving force between front and rear wheels according to a difference between a target yaw rate and an actually detected yaw rate is conventionally known (for example, Patent Document 1). reference). In this yaw motion control device, the target yaw rate is determined based on the steering angle of the front wheels and the vehicle speed, and the yaw rate of the vehicle is detected. A front-rear wheel drive amount distribution ratio is calculated according to the difference between the target yaw rate and the detected yaw rate, and the front and rear wheels of the vehicle are controlled based on the drive force distribution ratio to eliminate the difference between both yaw rates. Thus, the yaw motion of the vehicle is accurately controlled, and the desired steering performance in the vehicle can be accurately obtained.
Japanese Patent No. 3054265

  By the way, if hysteresis is added to the steering force when steering the wheels, the vehicle is prevented from reacting sensitively to a steering torque change that is not intended by the driver when the vehicle runs at high speed. The As a result, the stability of the vehicle is improved. On the other hand, if hysteresis is applied in consideration of high-speed traveling, the problem arises that the return performance of the steering during low-speed traveling deteriorates. As described above, the hysteresis applied to the steering force affects the steering performance when the vehicle is traveling.

  In this regard, the yaw motion control device disclosed in Patent Document 1 controls the front and rear wheels in accordance with the difference between the target yaw rate and the detected yaw rate, so that desired steering performance is obtained. . However, since the hysteresis imparted to the steering force is not taken into consideration, there is a problem that it is difficult to obtain stable steering performance at both high speed running and low speed running.

  Accordingly, an object of the present invention is to provide a braking / driving force control device for a vehicle that can obtain stable steering performance at both high speed running and low speed running by performing control in consideration of steering force hysteresis. Is to provide.

The braking / driving force control device for a vehicle according to the present invention that has solved the above problems includes a target yaw rate calculation means for calculating a target yaw rate based on the driving state of the vehicle, and an actual yaw rate that detects an actual yaw rate that is the actual yaw rate of the vehicle. Based on the steering angular velocity acquired by the detection means, the steering angular velocity acquisition means for acquiring the steering angular velocity in the vehicle, the target hysteresis acquisition means for acquiring the target hysteresis with respect to the steering torque of the vehicle, and the target angular velocity, the target hysteresis is obtained. The difference between the target yaw rate and the actual yaw rate is determined by the yaw moment calculating means for calculating the yaw moment to be realized, the braking / driving force distribution calculating means for calculating the braking / driving force distribution for the left and right wheels of the vehicle that achieves the yaw moment. When the vehicle is below the threshold, braking / driving the left and right wheels of the vehicle with braking / driving force distribution Comprising a wheel braking-driving means that the steering operation direction determining means for determining a steering operation of the vehicle, a braking-driving force distribution calculating means in calculating the braking-driving force distribution in the front wheels of the vehicle, supporting a front wheel Considering the kingpin offset amount of the front suspension, if the steering operation is an operation in the increasing direction, the front wheel is determined as the wheel to apply the yaw moment, and the steering operation is in the returning direction In this case, the rear wheel is determined as the wheel to which the yaw moment is applied .

  In the braking / driving force control device according to the present invention, the yaw moment that achieves the target hysteresis is calculated, and the left and right wheels of the vehicle are braked and driven by the braking / driving force distribution that achieves this yaw moment. For this reason, a desired hysteresis can be imparted to the steering force not only when the vehicle is traveling at a high speed but also when the vehicle is traveling at a low speed. Therefore, by performing the control in consideration of the hysteresis of the steering force, it is possible to obtain a stable steering performance at both high speed running and low speed running.

  Thus, in calculating the braking / driving force distribution on the front wheels in the vehicle, by adding the kingpin offset amount of the front suspension that supports the front wheels, it is possible to more suitably provide hysteresis and achieve more stable steering performance. Can be obtained.

  As described above, when the yaw moment that achieves the target hysteresis is applied to the front wheels when the steering operation is an operation in the direction of increasing, a moment is generated in the direction of suppressing the roll on the front wheels. Similarly, if a yaw moment is applied to the rear wheels when the steering operation is an operation in the switchback direction, a moment is generated in the direction of suppressing the wheel roll on the rear wheels. For this reason, according to the present invention, stable steering performance can be obtained, and the roll behavior of the vehicle can also be suppressed.

  The wheel braking / driving control means may be an in-wheel motor provided on each wheel.

  Thus, since the wheel braking / driving control means is an in-wheel motor, the braking / driving force control can be easily and accurately performed.

  According to the braking / driving force control device for a vehicle according to the present invention, stable steering performance can be obtained in both high-speed driving and low-speed driving by performing control in consideration of steering force hysteresis. .

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. For the convenience of illustration, the dimensional ratios in the drawings do not necessarily match those described.

  FIG. 1 is a block diagram of a braking / driving force control device for a vehicle according to a first embodiment of the present invention. As shown in FIG. 1, the vehicle M is provided with a vehicle control ECU (Electronic Control Unit) 1. The vehicle M is provided with an inverter 2, a battery 3, and a yaw rate sensor 4.

  Further, the vehicle M is provided with a right front wheel WFR, a left front wheel WFL, a right rear wheel WRR, a left rear wheel WRL, and a steering S. Hereinafter, the right front wheel WFR and the left front wheel WFL may be collectively referred to as a front wheel WF, and the right rear wheel WRR and the left rear wheel WRL may be collectively referred to as a rear wheel WR.

  The right front wheel WFR is provided with a right front wheel drive motor 5FR. Similarly, the left front wheel WFL is provided with a left front wheel drive motor 5FL, the right rear wheel WRR is provided with a right rear wheel drive motor 5RR, and the left rear wheel WRL is provided with a left rear wheel drive motor 5RL. Hereinafter, the right front wheel drive motor 5FR, the left front wheel drive motor 5FL, the right rear wheel drive motor 5RR, and the left rear wheel drive motor 5RL may be collectively referred to as the drive motor 5.

  Further, the right front wheel WFR is provided with a right front wheel speed sensor 6FR. Similarly, the left front wheel WFL is provided with a left front wheel speed sensor 6FL, the right rear wheel WRR is provided with a right rear wheel speed sensor 6RR, and the left rear wheel WRL is provided with a left rear wheel speed sensor 6RL. Hereinafter, the right front wheel speed sensor 6FR, the left front wheel speed sensor 6FL, the right rear wheel speed sensor 6RR, and the left rear wheel speed sensor 6RL may be collectively referred to as a wheel speed sensor 6. Furthermore, the steering angle sensor 7 is provided in the steering S.

  The vehicle control ECU 1 is an electronic control unit including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output port, and the like, and performs braking / driving force control of the vehicle M.

  The inverter 2 is connected to the vehicle control ECU 1, and a battery 3 is connected to the inverter 2. Further, electricity is stored in the battery 3. The inverter 2 converts the electricity stored in the battery 3 into alternating current and supplies it to the drive motor 5. The vehicle control ECU 1 calculates the drive amount distribution of the right front wheel drive motor 5FR, the left front wheel drive motor 5FL, the right rear wheel drive motor 5RR, and the left rear wheel drive motor 5RL in the drive motor 5, and uses this drive amount distribution. A corresponding distribution signal is output to the inverter 2. The inverter 2 supplies the drive motor 5 with electricity distributed according to the distribution signal from the vehicle control ECU 1.

  The yaw rate sensor 4 is attached to a part of the vehicle body, for example, and detects the yaw rate of the vehicle M. The yaw rate sensor 4 outputs the detected yaw rate to the vehicle control ECU 1.

  The drive motor 5 is a so-called in-wheel motor, and rotates the wheel W by electricity supplied from the battery 3 and AC-converted by the inverter 2. The wheel speed sensor 6 detects the wheel speed of each wheel. The wheel speed sensor 6 outputs the detected wheel speed to the vehicle control ECU 1. The steering angle sensor 7 detects the steering angle SA of the steering S. The steering angle sensor 7 outputs the detected steering angle SA to the vehicle control ECU 1.

  In the braking / driving force control device according to the present embodiment, focusing on the relationship between the yaw moment, which is the moment in the yaw direction of the vehicle M, and the total restoring torque of the front wheels, by controlling the braking / driving force distribution to the left and right wheels, the steering Stabilize performance.

  Now, as the direction of the steering angular velocity SV of the steering wheel S, the direction that increases the left turn of the vehicle M is defined as a positive direction, and the yaw moment in the direction that increases the left turn of the vehicle M is defined as positive. At this time, if the vehicle M is given a yaw moment (hereinafter referred to as a “direct yaw moment”) DYM having the same sign as the sign of the steering angular velocity SV, the front wheel WF of the vehicle M is smaller than that of a turn only by steering. Turn with lateral force. For this reason, compared with the case where the direct yaw moment DYM is not applied, the tire position restoring torque Mzf is reduced, and as a result, the steering force is reduced. On the contrary, when the yaw moment (hereinafter referred to as “anti-yaw moment”) AYM of the sign opposite to the sign of the steering angular velocity SV is given to the vehicle M, compared to the case where the anti-yaw moment AYM is not given. Steering force becomes heavy.

  When the direct yaw moment DYM is applied to the vehicle M, the lateral force Fy_f can be expressed by the following equation (1). As can be seen from the equation (1), the lateral force Fy_f changes in proportion to the change of the direct yaw moment DYM. Further, the tire position restoring torque Mzf can be expressed as shown in the following equation (2). As can be seen from the equation (2), the tire position restoring torque Mzf also changes in proportion to the change in the direct yaw moment DYM. .

Fy_f = mf · a−DYM / lt (1)
Mzf = Fy_f · ξ = ξ · mf · a− (ξ / lt) · DYM (2)
Where Fy_f: front wheel total lateral force
mf: Front wheel load
a: Turning lateral acceleration
lt: Front tread
ξ: Trail

  This relationship is the same when the anti-yaw moment AYM is applied to the vehicle M, and the direct yaw moment DYM and the anti-yaw moment AYM have the same absolute value and the opposite signs. The direct yaw moment DYM and the anti-yaw moment AYM can be controlled by distributing the braking / driving force to the left and right wheels. From this, in the braking / driving force control device according to the present embodiment, by controlling the distribution of the braking / driving force to the left and right wheels, the front wheel total restoring torque is adjusted to give a desired hysteresis to the steering force. Thus, the steering performance is stabilized.

  Hereinafter, the operation of the braking / driving force control device according to the present embodiment will be described. FIG. 2 is a flowchart showing an operation procedure of the braking / driving force control device. In this example, control for giving a yaw moment to the rear wheel WR is performed.

  As shown in FIG. 2, in the braking / driving force control device according to the present embodiment, first, the vehicle state is detected (S1). As the detection of the vehicle state, specifically, the yaw rate (actual yaw rate) r of the vehicle M is detected by the yaw rate sensor 4. Further, the wheel speed sensor 6 detects the wheel speed of each wheel W, and calculates the vehicle speed V based on the wheel speed of each wheel W. Further, the steering angle SA of the steering S is detected by the steering angle sensor 7.

  The yaw rate sensor 4, the wheel speed sensor 6, and the steering angle sensor 7 output the detected yaw rate, wheel speed, and steering angle SA to the vehicle control ECU 1, respectively. In the vehicle control ECU 1, the vehicle speed of the vehicle M is calculated based on the wheel speed of each wheel W output from the wheel speed sensor 6.

  Next, the target yaw rate r_ref is calculated (S2). The target yaw rate r_ref is calculated based on the vehicle speed V of the vehicle M and the steering angle SA output from the steering angle sensor 7. Subsequently, a yaw rate difference Δr that is a difference between the actual yaw rate r detected in step S1 and the target yaw rate r_ref calculated in step S2 is calculated by the following equation (3) (S3).

  r−r_ref = Δr (3)

  After calculating the yaw rate difference Δr, it is determined whether or not to perform hysteresis control of the steering torque (S4). Whether or not to perform hysteresis control is determined by whether or not the absolute value of the yaw rate difference Δr is equal to or less than a predetermined hysteresis threshold value r_hys. As a result, when the absolute value of the yaw rate difference Δr is equal to or less than the hysteresis threshold r_hys and it is determined that the hysteresis control is not performed, the normal yaw control control is performed (S10), and the process is terminated as it is.

  On the other hand, when the absolute value of the yaw rate difference Δr is not less than or equal to the hysteresis threshold r_hys (is greater than or equal to the hysteresis threshold r_hys), hysteresis control is performed according to the following procedure. When performing the hysteresis control, in order to give hysteresis to the steering torque, a front wheel total restoration torque hysteresis target value Mz_hys serving as a target hysteresis is obtained by calculation (S5). The front wheel total restoration torque hysteresis target value Mz_hys is calculated, for example, by referring to the vehicle speed V detected in step S1 with respect to the front wheel total restoration torque hysteresis target value calculation map shown in FIG.

  In the map shown in FIG. 3, when the vehicle speed V is equal to or lower than the first predetermined value, the front wheel total restoration torque hysteresis target value Mz_hys is set to 0, exceeds the first predetermined value, and is equal to or lower than the second predetermined value. As the vehicle speed V increases, the front wheel total restoration torque hysteresis target value Mz_hys is increased. When the vehicle speed V exceeds the second predetermined value, the front wheel total restoration torque hysteresis target value Mz_hys is set to a constant value. Thus, when the vehicle speed V is low, no hysteresis is applied to the steering torque, and when the vehicle speed V is high, a desired hysteresis is applied to the steering torque.

  Subsequently, the steering angular velocity SV is calculated by calculation (S6). The steering angular velocity SV is calculated by differentiating the steering angle SA detected in step S1. Then, the target yaw moment DYM_abs corresponding to the front wheel total restoration torque hysteresis target value Mz_hys is calculated (S7). The direction of the target yaw moment DYM_abs is determined by the operation direction of the steering wheel S. When the steering S is operated in the direction of turning back, hysteresis is given to the steering force by generating the direct yaw moment DYM as the yaw moment. On the other hand, when the steering wheel S is operated in the direction of increasing, the anti-yaw moment AYM is generated as the yaw moment, thereby giving hysteresis to the steering force.

  Further, the target yaw moment DYM_abs for giving the front wheel total restoring torque hysteresis target value Mz_hys can be expressed by the following equation (4). The target yaw moment DYM_abs for giving the front wheel total restoration torque hysteresis target value Mz_hys is calculated by the equation (4).

DYM_Abs = (Mz_hys / 2) · (lt / ξ) (4)
Where lt: Front tread
ξ: Trail

  Further, the direct yaw moment DYM for realizing the front wheel total restoring torque hysteresis target value Mz_hys is expressed by the following equation (5). In addition, FIG. 4 shows the relationship between the steering angular velocity SV and the direct yaw moment DYM based on the equation (5).

  DYM = −DYM_abs · sign (SV) (5)

  Further, the distribution of braking / driving force to the left and right wheels is calculated (S8). The relationship between the direct yaw moment DYM and the driving force to one wheel Fx (braking force is -Fx) is such that the absolute value of the driving force relating to the left and right wheels is the same and the direction is reversed (6) Represented by an expression. Therefore, the distribution of braking / driving force to the left and right wheels is calculated by the calculation shown in the following equation (6).

  Fx = DYM / lt (6)

  Thus, when the distribution of the braking / driving force to the left and right wheels is calculated, the driving force is generated for the left and right wheels (S9). The driving force for the left and right wheels is generated by the drive motor 5. The vehicle control ECU 1 transmits a distribution signal relating to the distribution of the calculated braking / driving force to the inverter 2. Based on the distribution signal transmitted from the vehicle control ECU 1, the inverter 2 supplies power to the right front wheel drive motor 5FR, the left front wheel drive motor 5FL, the right rear wheel drive motor 5RR, and the left rear wheel drive motor 5RL in the drive motor 5. To allocate. Thus, the control by the braking / driving force control device is completed. By performing such braking / driving force distribution, it is possible to add hysteresis to the steering torque. By giving hysteresis to the steering torque, as shown in FIG. 5, the vehicle response can be widened, and a stable steering performance can be obtained accordingly.

  In addition, when performing the braking / driving force distribution control for the left and right wheels, if the braking force distribution for the rear wheel WR is performed, a desired target hysteresis can be imparted to the steering torque by the above equations (1) to (6). Become. Further, when the braking force is distributed to the front wheel WF that is the steered wheel, there is a kingpin offset of the front suspension, which is different from the above formulas (1) to (6).

  Now, the tire position restoration torque Mzf at the time of control using the front wheel WF is added to the above equation (2) according to the mechanism that generates the steering torque due to the kingpin offset, and the following equation (7) expressed.

Mzf = ξ · mf · a− (ξ / lt) · DYM + KO · (Fx1−Fx2) (7)
Here, KO: King pin offset of front suspension Fx1: Driving force of front left wheel (when driving is positive)
Fx2: Front right wheel drive force (positive during drive)

  The direct yaw moment DYM is expressed by the following equation (8) using the driving forces Fx1 and Fx2 of the front left and right wheels.

  DYM = (lt / 2). (Fx2-Fx1) (8)

  For this reason, when the braking force is distributed to the front wheels WF, the tire position restoring torque Mzf expressed by the above equation (2) is expressed by the following equation (9).

  Mzf = ξ · mf · a − {(ξ + 2 · KO) / lt} · DYM (9)

  Further, the target yaw moment DYM_abs expressed by the above equation (4) is expressed by the following equation (10).

  DYM_Abs = (Mz_hys / 2) · {lt / (ξ + 2 · KO)} (10)

  Thus, hysteresis can also be provided to the steering torque by applying the direct yaw moment DYM to the front wheel WF. At this time, by taking into account the kingpin offset of the front suspension in the front wheel WF, it is possible to more suitably provide hysteresis and obtain more stable steering performance.

  Next, a second embodiment of the present invention will be described. The braking / driving force control device according to the present embodiment has the same configuration as the braking / driving force device according to the first embodiment, and the control mode is different. Hereinafter, the control mode will be described. In the braking / driving force control device according to the present embodiment, the braking / driving force is applied to either the front wheel WF or the rear wheel WR in order to reduce the roll behavior simultaneously with the application of hysteresis to the steering torque in consideration of the suspension characteristics. Apportion.

  When hysteresis is applied to the steering torque, the anti-yaw moment AYM is applied when the steering angle SA is being increased, and the direct yaw moment DYM is applied when the steering angle is switched back. On the other hand, from the relationship between the braking / driving force and the suspension characteristics, a roll moment RM shown in the following equations (11) and (12) is generated with the addition of the left / right difference of the braking / driving force. Among these, the roll moment RM generated when the front wheel braking / driving force control is performed is shown in the equation (11), and the roll moment RM generated when the rear wheel braking / driving force control is performed is shown in the equation (12).

RM = Anf · DYM (11)
RM = −Anr · DYM (12)
Where Anf: anti-dive coefficient
Anr: Antilift coefficient

  As shown in FIG. 6, the anti-dive coefficient in the above equation (11) has a positive angle between the straight line rising from the contact point of the front wheel WF with the ground in the vehicle M and the ground. The anti-lift coefficient is positive when the angle between the straight line rising from the contact point with the ground of the rear wheel WR in the vehicle M and the ground is positive.

  Here, the direct yaw moment DYM and the roll moment RM have the relationship shown in FIG. In FIG. 7, regarding the yaw moment, the direction in which the yaw moment is increased in the direction steered by the driver is positive. Moreover, about the roll, the roll to the turning outer side is made positive.

  As can be seen from FIG. 7, when an anti-yaw moment AYM is applied to give hysteresis to the steering torque, a moment is generated in the direction of suppressing the roll on the front wheel WF, and in the direction of promoting the roll on the rear wheel WR. A moment is generated. In addition, when applying a direct yaw moment DYM to give hysteresis to the steering torque, a moment is generated in the direction of promoting the roll in the front wheel WF, and a moment is generated in the direction of suppressing the roll in the rear wheel WR. To do.

  Further, FIG. 8 shows the roll behavior when the control for applying the direct yaw moment DYM only to the front wheel WF is shown, and FIG. 9 shows the roll behavior when the control for giving the direct yaw moment DYM only to the rear wheel WR. . As shown in FIGS. 8 and 9, in either control, the roll on one side on either the additional side or the back side becomes larger.

  Using this relationship, in the braking / driving force control according to the present embodiment, the braking / driving force distribution to the front wheels WF and the rear wheels WR is performed, and the rolling behavior of the vehicle M is controlled while giving hysteresis to the steering force. Control to suppress. Hereinafter, the operation procedure of the braking / driving force control according to the present embodiment will be described. FIG. 10 is a flowchart showing an operation procedure of braking / driving force control according to the present embodiment.

  As shown in FIG. 10, in the braking / driving force control according to the present embodiment, first, the vehicle state is detected (S11), and then the target yaw rate r_ref is calculated (S12). Subsequently, a yaw rate difference Δr that is a difference between the actual yaw rate r and the target yaw rate r_ref is calculated (S13), and it is determined whether or not the steering torque hysteresis control is performed (S14).

  As a result, when it is determined that the hysteresis control of the steering torque is not performed, the normal yaw control control is performed (S23), and the process is terminated as it is. On the other hand, when it is determined that the steering torque hysteresis control is to be performed, the front wheel total restoration torque hysteresis target value Mz_hys is obtained by calculation (S15), and the steering angular velocity SV is obtained by calculation (S16). Up to this point, the same procedure as in the first embodiment is performed.

  Subsequently, it is determined whether or not the operation of the steering wheel S is an additional operation (S17). Judgment whether or not the operation of the steering wheel S is an additional operation is performed based on the steering angle SA transmitted from the steering angle sensor 7 and acquired in step S1 and calculated in step S16.

  As a result, when it is determined that the operation of the steering wheel S is an additional operation, anti-yaw moment control for applying an anti-yaw moment to the front wheel WF is performed (S18). On the other hand, when it is determined that the operation of the steering wheel S is not a turning-up operation (a turning-back operation), yaw moment control for applying a yaw moment to the rear wheel WR is performed (S19). In this way, when the steering wheel S is increased, an anti-yaw moment is applied to the front wheel WF, and when the steering wheel S is switched back, a yaw moment is applied to the rear wheel WR, as shown in FIG. Thus, the roll behavior of the vehicle M can be suppressed.

  After that, as in the first embodiment, the target yaw moment is calculated (S20), and the left and right wheel braking / driving force distribution is calculated by calculation (S21). Then, control for generating driving force on the left and right wheels is performed (S22), and braking / driving force control is terminated.

  Thus, in the braking / driving force control according to the present embodiment, hysteresis can be imparted to the steering torque as in the first embodiment, and stable steering performance can be obtained. Furthermore, in the braking / driving force control device according to the present embodiment, the direction in which the roll of the vehicle M is suppressed when the yaw moment is applied to the wheels of the vehicle M, specifically, the operation of the steering wheel S is an additional operation. In this case, an anti-yaw moment is applied to the front wheel WF, and a direct yaw moment is applied to the rear wheel WR when the operation of the steering wheel S is a switchback operation. For this reason, while being able to give a hysteresis to steering torque, the roll which arises in the vehicle M can be suppressed.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, in the above embodiment, the drive motor 5 is attached to the wheel W in order to apply the braking / driving force to the vehicle M. However, for example, the driving force of the engine is transmitted to the wheel and the differential device is used to drive the differential device. Braking / driving force control for adjusting the distribution can also be performed.

  Further, in the above embodiment, when the hysteresis is applied to the steering torque, the direct yaw moment and anti-yaw moment applied to the wheels W are fixed values, but may be values according to the vehicle state and the like. For example, control is performed to increase the direct yaw moment or anti-yaw moment applied to the wheel W as the vehicle speed increases, or the direct yaw moment or anti-yaw applied to the wheel W as the lateral acceleration applied to the vehicle M increases. Control to increase or decrease the moment can be performed. For example, by performing control to increase the direct yaw moment or anti-yaw moment applied to the wheel W as the vehicle speed increases, stability in a high speed range can be ensured. Further, by performing control to increase the direct yaw moment and anti-yaw moment applied to the wheels W as the lateral acceleration applied to the vehicle M increases, it is possible to secure the rudder in the high acceleration range. Conversely, by performing control to reduce the direct yaw moment and anti-yaw moment applied to the wheels W as the lateral acceleration applied to the vehicle M increases, the lightness can be improved.

It is a block block diagram of the braking / driving force control device according to the first embodiment. It is a flowchart which shows the operation | movement procedure of the braking / driving force control apparatus which concerns on 1st Embodiment. It is a front wheel total restoration torque hysteresis target value calculation map. It is a graph which shows the relationship between a steering angular velocity and a direct yaw moment. It is a graph which shows the relationship between steering torque and vehicle responsiveness. It is a side view of a vehicle explaining an anti dive coefficient and an anti lift coefficient. It is a graph which shows the relationship between a roll moment and a yaw moment. 4 is a graph showing a relationship between a steering angle and a roll angle when a direct yaw moment is applied to a front wheel. 6 is a graph showing a relationship between a steering angle and a roll angle when an anti-yaw moment is applied to a rear wheel. It is a flowchart which shows the operation | movement procedure of the braking / driving force control apparatus which concerns on 2nd Embodiment. 6 is a graph showing a relationship between a steering angle and a roll angle when a direct yaw moment is applied to a front wheel or an anti-yaw moment is applied to a rear wheel.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle control ECU, 2 ... Inverter, 3 ... Battery, 4 ... Yaw rate sensor, 5 ... Drive motor, 6 ... Wheel speed sensor, 7 ... Steering angle sensor, M ... Vehicle, S ... Steering, W ... Wheel.

Claims (2)

Target yaw rate calculating means for calculating a target yaw rate based on the driving state of the vehicle;
An actual yaw rate detecting means for detecting an actual yaw rate that is an actual yaw rate of the vehicle;
Steering angular velocity acquisition means for acquiring a steering angular velocity in the vehicle;
Target hysteresis acquisition means for acquiring target hysteresis with respect to the steering torque of the vehicle;
A yaw moment calculating means for calculating a yaw moment for realizing the target hysteresis based on the steering angular speed acquired by the steering angular speed acquiring means;
Braking / driving force distribution calculating means for calculating braking / driving force distribution for the left and right wheels of the vehicle that achieves the yaw moment;
Wheel braking / driving means for braking / driving the left and right wheels of the vehicle by the braking / driving force distribution when a difference between the target yaw rate and the actual yaw rate is a predetermined threshold value or less;
Steering operation direction determination means for determining the steering operation of the vehicle;
With
The braking / driving force distribution calculating means calculates the braking / driving force distribution on the front wheels of the vehicle.
Taking into account the kingpin offset amount of the front suspension that supports the front wheel,
When the steering operation is an operation in the direction to increase the steering wheel, a front wheel is determined as a wheel to which the yaw moment is applied, and when the steering operation is an operation in the return direction, the yaw moment is determined. A braking / driving force control device for a vehicle, characterized in that a rear wheel is determined as a wheel for imparting a torque. The vehicle braking / driving force control device according to claim 1 , wherein the wheel braking / driving means is an in-wheel motor provided on each wheel.

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