JP2000168525A - Vehicle turning characteristic control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a driving by maneuverability by which a driving operation is easy to be performed by deciding the state of a road on which a vehicle travels and adjusting braking force of each of left and right wheels so that a turning characteristic based on a steering operation may be changed. SOLUTION: A road state deciding unit 10 decides the state of a road on which a vehicle travels based on detection signals from a yaw rate sensor 11, a brake pedal stroke sensor 12 and a speed sensor 13. A braking control unit 30 controls a braking system based on detecting signals from a steering angle sensor 16, the speed sensor 13 and a brake pedal stroke sensor 13, as decision results in the road state deciding unit 10 and a driver will deciding unit 20. In the braking system, a right front wheel braking actuator 31, a right rear wheel braking actuator 32, a left front wheel braking actuator 33 and a left rear wheel braking actuator 34 are provided. As a result, a steering operation can be changed according to maneuverability of the vehicle, the state of the road, a liking of the driver and necessity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle turning characteristic control device, and more particularly, to a vehicle turning characteristic of a vehicle based on a steering operation in accordance with a driver's preference or necessity or road conditions. The present invention relates to a vehicle turning characteristic control device that controls a braking system of a vehicle.

[0002]

2. Description of the Related Art Generally, vehicle turning characteristics (so-called understeer (US) and oversteer (OS)) based on a steering operation of a vehicle are determined based on vehicle specifications such as a structure for installing steered wheels and a structure of a steering system. It is uniquely determined for each vehicle. Further, on a curved road, when the steering angle with respect to the vehicle speed is not appropriate and a so-called understeer situation occurs, a vehicle behavior control device that strengthens the wheel braking force inside the curve so that the vehicle returns to an appropriate traveling locus. (For example, Japanese Patent Application Laid-Open No. 9-48338).

[0003]

By the way, the state of the road on which the vehicle travels changes variously, such as following a straight road or continuing a curved road. Further, the radius of the curve of the curved road also varies. When the vehicle turning characteristics based on the steering operation are fixedly determined as described above, the vehicle turning characteristics are not always easy to drive under various road conditions.

[0004] Further, the driver's preference for the steering operation feeling is not always constant, and the turning characteristics of the vehicle are such as those who prefer a so-called oversteer, those who prefer a so-called understeer, those who prefer a state where they are not both. There are various. Further, in a situation in which an obstacle in front of the vehicle is to be avoided urgently, it is necessary to further improve the turnability (make the vehicle slightly over-steered) to make it easier to avoid the obstacle than the normal turning characteristics of the vehicle. May be preferred.

[0005] In the above situation, as in the prior art, when the turning characteristics of the vehicle are uniquely determined,
A conventional vehicle behavior control device that controls a braking system so as to change the turning characteristics of the vehicle only when the vehicle has deviated from an appropriate traveling trajectory cannot sufficiently respond. Therefore, an object of the present invention is to provide a vehicle turning characteristic control device that can change the turning performance of a vehicle based on a steering operation according to road conditions, driver preferences, and necessity.

[0006]

According to the present invention, there is provided a vehicle turning characteristic control device for controlling a turning characteristic of a vehicle by a steering operation. Adjustment of the braking force of each of the left and right wheels so that the turning characteristics based on the steering operation are changed according to the determination result of the road condition determination means during the steering operation and the road condition determination means for determining the state of the road on which the vehicle is traveling. And a braking force balance adjusting means.

In such a vehicle turning characteristic control device, at the time of steering operation, the turning characteristics based on the steering operation are changed by controlling the braking force of each of the left and right wheels according to the road condition. Therefore, even if the road condition changes, it is possible to realize the driving with the turning performance that facilitates the driving operation in the road condition. For example, in a road condition in which a straight road continues for a long time, the braking force on each of the left and right wheels is adjusted to slightly lower the turning ability (understeering). Specifically, the braking force of the wheel on the outer side in the turning direction based on the steering operation is made slightly larger than the braking force of the wheel on the inner side (when the braking operation is not performed, the braking force on the inner vehicle is zero). . In such a case, the turning responsiveness of the vehicle to the steering operation is eased, and driving on a long straight road becomes easier.

Further, for example, in a road condition where a sharp curve continues, the braking force on each of the left and right wheels is adjusted so as to slightly increase the turning performance (oversteer). Specifically, the braking force of the inner wheel in the turning direction based on the steering operation is made slightly larger than the braking force of the outer wheel (when the braking operation is not performed, the braking force of the outer wheel is zero). . In such a case, the turning responsiveness of the vehicle to the steering operation is increased, and the vehicle can be turned more faithfully by the steering operation, so that driving on a road with a sharply continuous curve becomes easier.

The turning characteristic refers to the degree of turning of the vehicle with respect to the amount of steering operation. The road condition determining means can indirectly determine the condition of the road based on the driving operation of the driver or the driving condition of the vehicle, or can directly determine the condition of the road based on image information obtained by a camera or the like. Can also. The road conditions are road conditions that are expected to affect the driving operation of the driver, and include unevenness, inclination,
It includes the shape of the road itself, such as a curved shape, and environmental conditions, such as crosswinds and obstacles, which are external conditions of the road that are expected to affect the driver's driving operation.

In the case of the former, according to the present invention, the road condition determining means includes a road shape determining means for determining a shape of a road on which the vehicle travels, and the braking force balance adjustment is performed. The means is configured to adjust the braking force of each of the left and right wheels so that the turning characteristic based on the steering operation changes according to the determination result of the road shape determining means.

In such a vehicle turning characteristic control device, as described above, the driving operation is more facilitated by adjusting the left and right braking forces according to the shape of the road (curve conditions, etc.) during steering operation. The steering operation can be performed based on the turning performance of the vehicle. In the latter case, according to the present invention, as set forth in claim 3, the road condition determining means includes a road environment condition determining device for determining an environmental condition of a road on which the vehicle runs, and the braking force balance is determined. The adjusting means, according to the determination result of the road environment condition determining means,
As the turning characteristics based on the steering operation change,
It is configured to adjust the braking force of each of the left and right wheels.

In such a vehicle turning characteristic control device, the braking force of each of the left and right wheels is adjusted in accordance with the environmental condition of the road (crosswind, obstacle, etc.), so that the steering can be performed with a turning performance more suitable for the condition. Operations can be performed. For example, in a situation where a steering operation is performed while performing a sudden braking operation in order to avoid an obstacle in front of the vehicle, the turning property is increased (a little oversteer) so that the obstacle can be easily avoided. it can.

Further, for example, in a strong crosswind situation, it is possible to increase the turning performance in the direction toward the crosswind (oversteer) so as to easily withstand the lateral force on the vehicle due to the crosswind. According to a fourth aspect of the present invention, there is provided a vehicle turning characteristic control device for controlling a turning characteristic of a vehicle by a steering operation. Operating feeling determining means for performing, and braking force balance adjusting means for adjusting the braking force of each of the left and right wheels so as to change a turning characteristic based on the steering operation according to a determination result of the operating feeling determining means during steering operation. It is comprised so that it may be provided.

In such a vehicle turning characteristic control device, the turning characteristic of the vehicle based on the steering operation can be changed in accordance with the driver's favorite steering operation feeling. The driver's favorite steering operation feeling corresponds to the preference such as higher turning performance as turning performance, lower turning performance as turning performance, etc., and for drivers who prefer so-called sporty running, it is generally A steering operation feeling that enhances the turning performance (turning response to steering operation) is preferred. In addition, for a driver who prefers traveling with low turn response on a straight road or the like, generally, a steering operation feeling in which the turning performance is low is preferred.

Therefore, for example, for a driver who likes sporty running, in a situation where the steering operation is performed while performing the braking operation, the braking force of each of the left and right wheels is adjusted so that the turning performance is slightly increased (oversteering is slight). Is done. On the other hand, for a driver who prefers traveling with low turning response, the turning performance is slightly reduced (understeer is likely to occur).
Thus, the braking force of each of the left and right wheels is adjusted.

The driver's favorite steering operation feeling is:
The determination can be made according to the driving operation (the engine speed based on the accelerator operation or the braking operation, the vehicle speed, the state of acceleration / deceleration, the state of the selected gear position, and the like). The determination can also be made by the driver directly inputting information corresponding to a desired steering operation feeling into the device. In the former case, as described in claim 5, the operation feeling determination means is configured to determine the driver's steering operation feeling based on the driving operation of the driver.

In the latter case, the operation feeling determining means includes turning performance specifying means for specifying turning performance by a driver's operation. The designated turning performance is determined as the driver's favorite steering feeling. As described above, in the vehicle turning performance control device in which the information corresponding to the driver's favorite steering operation feeling is input by the turning performance specifying means, from the viewpoint of further simplifying the input operation. As described in the above, the turning performance specifying means includes a normal mode corresponding to a predetermined turning performance, an oversteer mode that increases turning performance as the turning performance, and a turning performance as the turning performance decreases. A mode selecting means for selecting any of the understeer modes may be provided, and the turning performance in the mode selected by the mode selecting means may be determined as a driver's favorite steering feeling.

From the viewpoint that the greater the steering operation, the greater the degree of increase or decrease in the turning performance of the vehicle, the present invention provides, in each of the above devices, The balance adjusting means can be configured to adjust the left and right braking forces so that the difference between the braking forces of the left and right wheels increases as the steering angle increases.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. A vehicle turning characteristic control device according to an embodiment of the present invention is configured, for example, as shown in FIG. In FIG. 1, the vehicle turning characteristic control device includes a road condition determining unit 10 and a driver intention determining unit 20.
And a braking control unit 30. The road condition determination unit 10 determines the condition of the road on which the vehicle travels based on the detection signals from the yaw rate sensor 11, the brake pedal stroke sensor 12, and the vehicle speed sensor 13. Specifically, it is determined whether or not the vehicle is in a road condition where a curve is continuous, and whether or not the vehicle requires an emergency braking due to an obstacle or the like. Driver intention determination unit 20
Determines whether the driver prefers sporty driving or normal driving (especially not sporty driving) based on detection signals from the vehicle speed sensor 13, the throttle opening sensor 14 and the engine rotation sensor 15. Do.

The braking control unit 30 is based on the judgment results of the road condition judging unit 10 and the driver intention judging unit 20 and further based on the detection signals from the steering angle sensor 16, the vehicle speed sensor 13 and the brake pedal stroke sensor 13. To control the braking system. The braking system controls the right front wheel braking actuator (A) so as to correspond to each of the left and right front wheels and the left and right rear wheels so that the braking force can be independently controlled.
c) 31, a right rear wheel brake actuator (Ac) 32, a left front wheel brake actuator (Ac) 33, and a left rear wheel brake actuator (Ac) 34 are provided.

A mode selection switch 40 is provided near the steering wheel or at a position such as a dash panel that can be operated during driver's driving operation. The mode selection switch 40 is, for example, capable of selecting between an automatic mode (A) and a manual mode (M) as shown in FIG. In the manual mode (M), the normal mode (N) and the oversteer mode (O
S) and understeer mode (US) can be selected.

The normal mode (N) is a mode in which a predetermined vehicle turning performance determined by the steering mechanism, the installation structure of the steered wheels, and the like is obtained with respect to the steering operation. The oversteer mode (OS) is a turning performance (turning property) higher than the predetermined vehicle turning performance for the steering operation.
Is obtained. The understeer mode (US) is a mode in which a turning performance (turning property) lower than the predetermined vehicle turning performance can be obtained with respect to a steering operation.

In the automatic mode (A), the vehicle turning performance in the normal mode (N), the oversteer mode (OS) and the understeer mode (US) is automatically adjusted according to the road condition and the driver's driving condition. This is the mode that can be obtained. The brake control unit 10 includes, for example, a table describing the relationship between the steering angle (right, left) and the braking pressure difference between the left and right wheels, as shown in FIG. In FIG. 3, in the characteristics Q1 (OS), Q2 (OS), and Q3 (OS), as the steering angle increases, the braking pressure (force) of the wheel inside the vehicle turning sequentially increases from the braking pressure of the outside wheel. growing. In such a situation, since a moment acts on the vehicle in the turning direction, the turning performance of the vehicle is increased (corresponding to oversteer).

On the other hand, characteristics Q1 (US), Q2 (US),
In Q3 (US), as the steering angle increases, the braking pressure on the wheel on the outer side of the vehicle turning becomes larger sequentially than the braking pressure on the wheel on the inner side. In such a situation, a moment in the direction opposite to the turning direction acts on the vehicle, so that the turning performance of the vehicle is reduced (corresponding to understeer).

Further, characteristics Q1 (OS), Q2 (OS),
Q3 (OS) and characteristics Q1 (US), Q2 (US), Q
3 (US) can be selected by a driver's selection operation on a key switch, a touch panel, or the like (not shown) provided near the mode selection switch 40, for example. The driver intention determination unit 20 determines whether the driver's preference is sporty driving or normal driving according to a known algorithm. Specifically, the driver's intention determining unit 20 has a configuration as shown in FIG. It is. 4, a throttle opening calculated based on a detection signal from a throttle opening sensor 14, an engine speed calculated based on a detection signal from an engine rotation sensor 15, and a detection signal from a vehicle speed sensor 12 are shown. The neural network (NN) 21 is supplied with information on the vehicle speed calculated by the vehicle, the gear position selected during traveling, and the acceleration / deceleration calculated based on the detection signal from the vehicle speed sensor 12. This neural network (NN)
Reference numeral 21 is designed to output a determination result (sports running, normal running) corresponding to a combination of the above-mentioned pieces of information supplied according to a predetermined logic.

The road condition judging unit 10 always judges the condition of the road on which the vehicle travels, for example, according to the procedure shown in FIG. In FIG. 5, the vehicle speed V and the acceleration / deceleration are calculated based on the detection signal from the vehicle speed sensor 12 (S1, S2). Further, a brake pedal stroke calculated based on a detection signal from the brake pedal stroke sensor 12 is obtained. These, vehicle speed,
From the changes in the acceleration / deceleration and the break pedal stroke, it is determined whether or not the driver is performing an emergency braking operation (S
4).

Here, if it is determined that the emergency braking operation is being performed, a determination result is output to increase the turning performance of the vehicle to facilitate avoiding an obstacle (S7). On the other hand, when it is determined that the driver has not performed the emergency braking operation, the yaw rate of the vehicle calculated based on the yaw rate sensor 11 is further obtained (S5). Then, the yaw rate and the vehicle speed obtained as described above,
Based on the acceleration / deceleration, it is determined whether or not the vehicle is currently traveling on a tight curve, that is, whether or not the turning performance should be improved (S6).

Here, if it is determined that the turning performance should be improved while the vehicle is traveling on a tight curve road, the determination result (OS instruction) is output (S7). As described above, while the vehicle is traveling, the driving intention determination unit 20 and the road condition determination unit 10 output the determination result according to the road condition or the driver's favorite driving. The braking control unit 30 to which such a determination result is supplied executes processing according to, for example, a procedure shown in FIG.

In FIG. 6, first, it is determined whether the driver's selection mode with the mode selection switch 40 is either the manual mode (M) or the automatic mode (A) (S).
11). Here, when the driver selects the manual mode (M) by operating the mode selection switch 40, any one of the manual modes (M) (normal mode (N), oversteer) It is determined whether the mode (OS) or the understeer mode (US) has been selected (S12, S13, S14).

When the normal mode (N) is selected, normal braking control is executed as the braking control (P100). That is, the braking control unit 30 controls the right front wheel braking actuator 31 and the right rear wheel braking actuator so that the braking pressure corresponding to the brake pedal stroke obtained based on the detection signal from the brake pedal stroke sensor 12 acts on each wheel. 32, left front wheel braking actuator 33 and left rear wheel braking actuator 3
4 is supplied with a control signal.

In the normal mode (N), the steering operation is not performed without particularly controlling the braking performance.
A predetermined turning performance determined by the steering mechanism, the installation structure of the steered wheels (front wheels) and the like can be obtained. When the driver wants a sporty steering operation feeling, the mode selection switch 40
Oversteer mode (O) of manual mode (M)
If S) is selected, the mode determination result (S1
3, YES), the vehicle speed V calculated based on the detection signal from the vehicle speed sensor 13 is obtained (S15), and the steering angle (rightward, leftward) calculated based on the detection signal from the steering angle sensor 16 is obtained. Is also acquired (S1)
6). Then, the braking pressure difference between the left and right wheels is calculated (S1).
7). In the calculation of the left and right braking pressure differences, the braking pressure difference between the left and right wheels corresponding to the steering angle is calculated according to the characteristics selected by the driver from the characteristics Q1 (OS), Q2 (OS), and Q3 (OS) shown in FIG. It is determined.

When the left and right braking pressure differences are determined as described above, the braking control (P100) is executed based on the brake pedal stroke obtained from the detection signal from the brake pedal stroke sensor 12 and the braking pressure difference between the left and right wheels. You. That is, the braking pressure on the inner wheel in the turning direction of the vehicle due to the steering operation is controlled to be slightly higher than the braking pressure on the outer wheel. More specifically, if the vehicle is turning right, in the situation where the steering operation is performed, the right front wheel braking actuator 31 and the right rear wheel braking actuator 32
The braking actuators are controlled so that the braking pressure generated by the brake actuator is slightly higher than the braking pressure generated by the left front wheel braking actuator 33 and the left rear wheel braking actuator. If the braking operation is not performed, the right front wheel braking actuator 31 and the right rear wheel braking actuator 3 are controlled so that the braking pressure acts only on the right front wheel and the right rear wheel.
2 is controlled. In the case of a left turn, in a similar situation, the braking pressure generated by the left front wheel braking actuator 33 and the left rear wheel braking actuator 34 is generated by the right front wheel braking actuator 31 and the right rear wheel braking actuator 32. So that it is slightly larger than the braking pressure,
Each braking actuator is controlled. Also in this case, if the braking operation is not performed, the left front wheel braking actuator 33 and the left rear wheel braking actuator 34 are controlled such that the braking pressure acts only on the left front wheel and the left rear wheel.

As a result, in the situation where the steering operation is performed, the movement of the vehicle to be turned is enhanced, and the turning performance higher than the above-mentioned predetermined turning performance is obtained for the steering operation (a little oversteer). As a result, the driver can obtain a desired vehicle turn with a relatively small amount of steering operation at the time of steering operation,
A more responsive and more sporty steering operation feeling can be obtained.

When the oversteer mode (OS) of the manual mode (M) is selected as described above, each of the above-described steps S11, S12, S13, S15, S16, S1 is performed.
7 and the braking control P100 are performed by the ignition
It is repeatedly executed until the switch is turned off (S18). On the other hand, when the driver desires a steering operation feeling with low turning performance on a straight road or the like and selects the understeer mode (US) of the manual mode (M) with the mode selection switch 40, the mode determination result (S14, YE
According to S), the vehicle speed V is obtained in the same manner as described above (S1).
5), acquisition of the steering angle (S16), and calculation of the difference between the braking pressures of the left and right wheels (S17). In the calculation of the left and right braking pressure differences, the respective characteristics Q1 (US) and Q2 (U
S) and the braking pressure difference between the left and right wheels corresponding to the steering angle is determined according to the characteristics selected by the driver from Q3 (US).

When the difference between the left and right braking pressures is determined in this manner, the brake pedal stroke sensor 1
Braking control (P10) based on the brake pedal stroke and the braking pressure difference between the left and right wheels obtained from the detection signal from
0) is executed. In other words, the braking pressure on the outer wheel in the turning direction of the vehicle due to the steering operation is controlled to be slightly higher than the braking pressure on the inner wheel. Specifically, if the vehicle is turning right, the braking pressure generated by the left front wheel braking actuator 33 and the left rear wheel braking actuator 34 in the situation where the steering operation is performed is reduced by the right front wheel braking actuator 31 and the left rear wheel braking actuator. Each braking actuator is controlled to be slightly greater than the braking pressure generated at 32. If the braking operation is not performed, only the left front wheel braking actuator 33 and the left rear wheel braking actuator 34 are controlled so that the braking pressure acts only on the left front wheel and the left rear wheel. In the case of a left turn, in a similar situation, the braking pressure generated by the right front wheel braking actuator 31 and the right rear wheel braking actuator 32 is generated by the left front wheel braking actuator 33 and the left rear wheel braking actuator 34. Each braking actuator is controlled to be slightly higher than the braking pressure. In this case, if the braking operation is not performed,
The right front wheel braking actuator 31 and the right rear wheel braking actuator 32 are controlled so that the braking pressure acts only on the right front wheel and the right rear wheel.

As a result, when the steering operation is performed while performing the braking operation, the movement of the vehicle to be turned is suppressed, and the turning performance lower than the predetermined turning performance is obtained for the steering operation (understeering). . As a result, the driver can obtain a desired vehicle turning with a relatively large steering operation amount during such a steering operation with a braking operation, and can obtain a steering operation feeling with relatively low turning performance on a straight road or the like. Obtainable.

When the understeer mode (US) of the manual mode (M) is selected as described above, each of the above-described steps S11, S12, S13, S14, S15, S1 is performed.
6. The processing in S17 and the braking control P100 are repeatedly executed until the ignition switch is turned off (S18). On the other hand, the driver operates the mode selection switch 4
When the automatic mode (A) is selected by the operation of 0, it is monitored whether or not the road performance determination unit 10 or the driver intention determination unit 20 determines the turning performance improvement (OS instruction). (S19). Here, for example, when the road condition determination unit 10 determines that the turning performance is to be improved in a road condition where a sharp curve road is continuous, a condition where emergency braking is required, or a condition of the driver's driving operation. If the driver's intention determination unit 20 determines that the turning performance is improved based on the above, steps S15 and S1 are performed in the same manner as in the above-described oversteer mode (OS).
6 and S17, the braking control P100 is executed. That is, the characteristic Q1 (O) shown in FIG.
The braking pressure difference between the left and right wheels according to the steering angle is determined according to the characteristics selected from S), Q2 (OS), and Q3 (OS). Then, the braking actuators 31, 32, 33, 34 for each wheel are controlled such that the braking force of the wheel on the inner side in the turning direction is slightly larger than the braking force of the wheel on the outer side.

As a result, in a road situation where a curved road continues, a turning performance higher than the above-mentioned predetermined turning performance can be obtained in a situation where the steering operation is performed (oversteer). Accordingly, in a situation where the driver travels on a curved road by performing a steering operation, a desired vehicle turn can be obtained with a relatively small amount of steering operation, and traveling on the curved road becomes easier.

In a situation where emergency braking is performed, a turning performance higher than the above-mentioned predetermined turning performance can be obtained during the sudden braking operation (oversteering). Accordingly, when the driver tries to avoid an obstacle by steering operation together with emergency braking operation, the vehicle can turn more steeply, and obstacle avoidance can be performed accurately.

Further, when the driver prefers a sporty steering operation feeling, as in the case of the above-described oversteer mode (OS), the driver can perform the steering operation with a relatively small amount of steering operation. A desired turning of the vehicle can be obtained, and a more responsive and sporty steering operation feeling can be obtained.

Further, according to the vehicle turning performance control device as described above, for example, in the case of so-called counter steering in which the steered wheels FLW and FRW are turned in a direction opposite to the turning direction L of the vehicle as shown in FIG. If the steering mode (OS) is selected, the braking pressure of the outer wheels FLW and RLW in the turning direction is always controlled to be greater than the braking pressure of the inner wheels FRW and RRW in the turning direction. Moment (anti-spin moment) acts in the direction. As a result, in such a situation in which the counter steering is performed, the operation becomes easier without requiring a large correction steering to stabilize the posture of the vehicle.

Further, when the vehicle receives a lateral force from a certain direction such as a cross wind, for example, when the vehicle receives a lateral force from the right side of the vehicle, the characteristics of the first and second quadrants shown in FIG. By performing the braking control so that the rightward moment acts on the vehicle at all times during the braking operation, a force against the rightward lateral force can be generated in the vehicle. When a lateral force is applied from the left side of the vehicle, the braking control is performed so that the moment in the left direction always acts on the vehicle according to the characteristics of the third and fourth quadrants shown in FIG. A force against the lateral force can be generated in the vehicle. Thus, in a situation where the vehicle receives a crosswind from a certain direction, the stability of the vehicle can be increased, for example, when a steering operation for changing lanes is performed.

In the above-described example, the road condition judging unit 10 which executes the processing according to the procedure shown in FIG. 5 corresponds to the road condition judging means.
The processes in S2, S5 and S6 correspond to the road shape determining means, and the processes in steps S1S2S3S4 shown in FIG. 5 correspond to the road environment condition determining means. Further, the driver intention determining unit 20 having the configuration shown in FIG. 4 corresponds to the operation feeling determining means, and the mode selection switch 40 corresponds to the turning performance specifying means.

[0044]

As described above, according to the present invention described in each of the claims, the road performance and the driver's intention are determined, and the turning performance for the steering operation is determined based on the determination results. Therefore, in a situation where a steering operation is performed, the turning performance of the vehicle based on the steering operation can be changed according to road conditions, driver's preference, and necessity.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a vehicle turning characteristic control device according to one embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of an appearance of a mode selection switch.

FIG. 3 is a diagram illustrating a relationship between a braking pressure difference between left and right wheels and a steering angle.

FIG. 4 is a block diagram showing a specific configuration of a driver intention determination unit.

FIG. 5 is a flowchart illustrating a procedure of processing in a road condition determination unit.

FIG. 6 is a flowchart showing a procedure of processing in a braking control unit.

FIG. 7 is a diagram showing a state of counter steering.

[Explanation of symbols]

 Reference Signs List 10 Road condition determination unit 11 Yaw rate sensor 12 Brake pedal stroke sensor 13 Vehicle speed sensor 14 Throttle opening sensor 15 Engine rotation sensor 16 Steering angle sensor 20 Driver intention determination unit 21 Neural network 30 Brake control unit 31 Right front wheel brake actuator 32 Right rear Wheel brake actuator 33 Left front wheel brake actuator 34 Left rear wheel brake actuator 40 Mode selection switch

Claims (8)

[Claims] 1. A vehicle turning characteristic control device for controlling a turning characteristic of a vehicle by a steering operation, comprising: road condition determining means for determining a state of a road on which the vehicle travels; A vehicle turning characteristic control device comprising: braking force balance adjusting means for adjusting the braking force of each of the left and right wheels so that the turning characteristic based on the steering operation changes according to the result. 2. The vehicle turning characteristic control device according to claim 1, wherein the road condition determining means includes a road shape determining means for determining a shape of a road on which the vehicle travels, and the braking pressure balance adjusting means includes: A vehicle turning characteristic control device that adjusts the braking force of each of the left and right wheels so that the turning characteristic based on a steering operation changes according to a determination result by a road shape determining unit. 3. The vehicle turning characteristic control device according to claim 1, wherein said road condition determining means includes road environment condition determining means for determining an environmental condition of a road on which the vehicle travels, and said braking pressure balance adjustment is performed. The vehicle braking control device adjusts the braking force of each of the left and right wheels so that the turning characteristic based on the steering operation changes according to the determination result of the road environment condition determining unit. 4. A vehicle turning characteristic control device for controlling turning characteristics of a vehicle by steering operation, comprising: an operation feeling determining means for determining a driver's favorite steering operation feeling; and a determination by the operation feeling determining means at the time of steering operation. A vehicle turning characteristic control device comprising: braking force balance adjusting means for adjusting the braking force of each of the left and right wheels so that the turning characteristic based on the steering operation changes according to the result. 5. The vehicle turning characteristic control device according to claim 4, wherein said operation feeling determining means determines a driver's favorite steering operation feeling based on the driver's driving operation. apparatus. 6. The vehicle turning characteristic control device according to claim 4, wherein said operation feeling determining means includes turning performance specifying means for specifying turning performance by a driver's operation, and said turning feeling specifying means specifies the turning performance. A turning characteristic control device that determines the turning performance as a driver's favorite steering feeling. 7. The vehicle turning characteristic control device according to claim 6, wherein the turning performance specifying means includes a normal mode corresponding to a predetermined turning performance, an oversteer mode for increasing turning performance as the turning performance, and a turning operation. Mode selection means for selecting any of the understeer modes for reducing the turning performance as performance is provided, and the turning performance in the mode selected by the mode selection means is determined as the driver's favorite steering feeling. Vehicle turning characteristic control device. 8. The vehicle turning characteristic control device according to claim 1, wherein the braking pressure balance adjusting means includes a braking force balance adjusting means for increasing the steering angle so that the difference between the braking forces of the left and right wheels increases. A vehicle turning characteristic control device that adjusts a braking force.