JP2007091029A - Vehicular damping force control device, and vehicular damping force controlling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular damping force control device and the like capable of improving vehicle stability when requiring sudden brake, and ride comfort. <P>SOLUTION: A function estimating the possibility of brake operation by a recognition result of an obstacle recognizing device 9 so as to control an actuator 2 adjusting generated damping force by a shock absorber 3 damping vibrations added to a vehicle; and a function controlling the actuator 2 to generate predetermined damping force when it is estimated that brake operation is not carried out, and starting the controlling of the actuator so as to generate damping force higher than the predetermined damping force before the brake operation when it is estimated that the possibility of carrying out the brake operation is high, are mounted on an ECU1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle damping force control device and a vehicle damping force control method for controlling damping force generated by a shock absorber that suppresses vertical vibration applied to a vehicle.

  Conventionally, a technique that includes a shock absorber that suppresses vertical vibration of a vehicle in order to ensure the ride comfort of the vehicle and adjusts the damping force of the shock absorber by actuator control is known in Patent Document 1 below. .

The technique described in Patent Document 1 detects road information, current location, vehicle speed, inter-vehicle distance from other vehicles, etc. as vehicle status, determines the necessity of deceleration according to the vehicle status, and performs deceleration operation. When detecting that it has started, the damping force of the shock absorber is adjusted.
Japanese Patent Laid-Open No. 11-115545 (see claims 1, 2, 5, paragraphs 0071, 0081)

  However, in the technique described in Patent Document 1 described above, since the adjustment of the damping force is started when the deceleration operation by the driver is detected, for example, when the vehicle is suddenly decelerated, the damping force by the shock absorber is increased. There is a problem that the vehicle decelerates before it occurs, and then a large damping force is generated by the shock absorber. In other words, if the damping force generated by the shock absorber is delayed after sudden deceleration, a nose dive occurs in which the vehicle suddenly decelerates due to the braking force, causing the vehicle to lean forward.

  Accordingly, the present invention has been proposed in view of the above-described circumstances, and a vehicle damping force control device and a vehicle damping force that can improve vehicle stability by improving vehicle stability when sudden braking is required. An object is to provide a control method.

  The present invention relates to a brake operation predicting means for predicting the possibility of a brake operation for controlling an actuator for adjusting a damping force generated by a shock absorber that attenuates vibration applied to a vehicle, and a brake operation predicting means If it is predicted that no operation will be performed, the damping force control means controls the actuator so as to generate a predetermined damping force. On the other hand, in order to solve the above problem, the brake operation prediction means If it is predicted that the operation is likely to be performed, the damping force control means controls the actuator so that a damping force higher than a predetermined damping force is generated before the braking operation is performed. Start.

  According to the present invention, when it is predicted that a brake operation is likely to be performed, the actuator control is performed so that a damping force higher than a predetermined damping force is generated before the brake operation is performed. Therefore, sudden braking is required by reducing the difference between the front wheel load and the rear wheel load when the brake is actually operated, and reducing the difference between the front wheel stroke amount and the rear wheel stroke amount of the suspension. Riding comfort can be improved by improving vehicle stability.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The present invention is applied to, for example, a vehicle control device configured as shown in FIG.

  This vehicle control device includes an ECU (Electric Control Unit) 1, an actuator 2 and a shock absorber 3 to be controlled, a sprung vertical G sensor 4 for detecting vehicle conditions, a sprung vertical G sensor 5 and a steering angle. A sensor 6, a vehicle speed sensor 7, a stop lamp switch 8, and an obstacle recognition device 9 are connected.

  The ECU 1 performs a brake operation on the vehicle based on the sensor signal from the unsprung vertical G sensor 4, unsprung vertical G sensor 5, rudder angle sensor 6, vehicle speed sensor 7, and obstacle recognition result from the obstacle recognition device 9. The possibility of being made is judged, and when the possibility is high, the damping force by the shock absorber 3 is increased in advance.

  The actuator 2 and the shock absorber 3 show the relationship between the wheel load of the vehicle and the maximum diamond force (braking force by the tire) in FIG. When the maximum tire force is set to a predetermined value and a sudden braking of the vehicle is predicted, the wheel load is set to a value lower than the predetermined value and the maximum tire force is set to a value higher than the predetermined value.

  The actuator 2 operates so as to adjust the flow resistance when the fluid passes through the aperture by adjusting the aperture through which the fluid (oil) passes in the shock absorber 3 by position control of the valve body. The actuator 2 increases the damping force against the vibration that the vehicle receives from the road surface by increasing the flow resistance of the fluid in the shock absorber 3, and conversely, the vehicle receives from the road surface by decreasing the flow resistance in the shock absorber 3. Reduce the damping force against vibration.

  The actuator 2 and the shock absorber 3 include an actuator 2RF and a shock absorber 3RF for suppressing the vibration damping force on the right front wheel of the vehicle, an actuator 2LF and a shock absorber 3LF for suppressing the vibration damping force on the left front wheel of the vehicle, The actuator 2RB and the shock absorber 3RB for suppressing the vibration damping force on the right rear wheel of the vehicle, and the actuator 2LB and the shock absorber 3LB for suppressing the vibration damping force on the left rear wheel of the vehicle.

In such a vehicle control apparatus, as shown in FIG. 3A, a suspension (spring) is inserted between the vehicle M and the traveling ground surface, and the unsprung vibration force applied to the suspension from the traveling ground surface. the X ₀ and is capable of detecting the vertical G sensor 5 under spring. Vertical vibration force given from the running contact surface to the vehicle M via a suspension, when the vertical direction of the unsprung vibration force X ₀ is detected by the vertical G sensor 5 under spring appears as a spring vibration force X ₁ . In contrast, the shock absorber 3, when a is attached to the upper portion of the vehicle M, reverse damping force to cancel spring vibration force X ₁ applied to the vehicle M gives the (reaction force) F. Relationship between the damping force F of the spring vibration force X ₁ and the shock absorber 3 applied to the vehicle M is
F = C1X ₁
It becomes. Here, C1 is a damping coefficient, and can be determined by experiments and calculations as an ideal operation of the shock absorber 3 that makes the vibration applied to the vehicle M substantially zero. Such sprung vibration force X _1, approach to attenuate shock absorber 3 is called a so-called skyhook theory.

  As shown in FIG. 3B, the vehicle control device to which the present invention is applied has a spring that detects vibration of the vehicle M in addition to the unsprung vertical G sensor 5 that detects vibration from the traveling ground surface of the vehicle M. The upper / lower G sensor 4 is attached to the vehicle M, the shock absorber 3 is disposed between the vehicle M and the traveling ground surface at a position parallel to the suspension, and the damping force F of the shock absorber 3 is controlled by the damping force control device. 11 to control.

When the downward vibration is applied to the vehicle M by the sensor signal from the sprung vertical G sensor 4 (X ₁ (X ₁ −X ₀ )> 0), the damping force control device 11 applies the shock absorber 3 to the shock absorber 3. ,
_{Fc = Cx (X 1 -X 0} ) = C1X 1
The damping coefficient Cx is determined so as to generate the damping force Fc calculated in (1). That is, when the spring vibration force X ₁ is downward operates the shock absorber 3 so as to generate a damping force Fc for attenuating the vibration of the the downward direction.

Further, when the upward vibration is applied to the vehicle M by the sensor signal from the sprung vertical G sensor 4 (X ₁ (X ₁ −X ₀ ) ≦ 0), the damping force control device 11 is a shock absorber. The damping force Fc generated in 3 is approximately 0 (Fc≈0).

  The damping force characteristic of the shock absorber 3 is set by the aperture area determined by the valve body position that gives flow resistance to the fluid, and the drive amount is controlled by the actuator 2 according to the above-described damping coefficient Cx. Adjusted by.

In this way, the vehicle control device that changes the damping force of the shock absorber 3 has a damping force control device 11 as shown in FIG. The damping force control device 11 includes a feedback (FB) control unit 21, integrators 22 and 23, and a sudden braking prediction device 24 connected to the obstacle recognition device 9. The damping force control device 11 includes a spring vibration force X ₁ as integrated value by detecting the sensor signals sprung G sensor 4 by the integrator 22, the unsprung vertical G sensor 5 of the sensor signal integrator 23 in supplying and unsprung vibration force X ₀ as detected integral value to the feedback control unit 21.

  Also, the obstacle recognition device 9 supplies obstacle information such as the distance between the vehicle and the obstacle to the sudden braking prediction device 24. The sudden braking predicting device 24 predicts from the obstacle information from the obstacle recognizing device 9 whether the vehicle is likely to be suddenly braked by a brake operation, and supplies the correction value of the damping coefficient Cx to the feedback control unit 21. To supply.

As shown in FIG. 3, the feedback control unit 21 determines the vehicle M from the sprung vibration force X ₁ and the unsprung vibration force X ₀ from the integrators 22 and 23 and the correction value from the sudden braking prediction device 24. spring vibration force X ₁ asks the damping coefficient Cx of the shock absorber 3 that can be absorbed by the shock absorber 3. In order to obtain the damping coefficient Cx, the feedback control unit 21 obtains the damping coefficient C1 corresponding to the above-described damping coefficient C according to the normal vertical vibration characteristics that do not require rapid deceleration as shown in FIG. The attenuation coefficient C1 and the correction value are added by the adder 31.

  Here, since the damping coefficient C1 is a value that determines the vertical vibration characteristic of the vehicle in a normal state, it is a value that can suppress the vehicle body vibration when traveling through the unevenness of the traveling ground surface rather than suppressing a sudden vertical change. Is preferably determined experimentally, and more preferably set in consideration of the characteristics of the vehicle (suspension characteristics, vehicle weight, etc.). Specifically, the damping coefficient C1 is set high when it is desired to improve the motion performance of the vehicle, and the damping coefficient C1 is set low when priority is given to riding comfort over the motion performance.

Then, the feedback control unit 21, the damping force calculating unit 32, using the addend C obtained by adding the correction value, and the vibration force X ₁ and the unsprung vibration force X ₀ spring damping coefficient C1, the damping coefficient Cx Ask for.

At this time, the damping force calculation unit 32 applies a downward vibration force to the vehicle.
_{Cx = C [X 1 / (} X 1 -X 0)]
The attenuation coefficient Cx is obtained with the following equation. Further, when upward vibration is applied to the vehicle, the added value C is directly used as the damping coefficient Cx.

  Thereby, when a correction value is given by the sudden braking prediction device 24, the damping coefficient Cx can be set to a higher value than the damping coefficient C1 that suppresses normal vibration, and the damping force of the vehicle can be increased.

  Next, in the vehicle control apparatus to which the present invention is applied, the operation when the damping force of the shock absorber 3 is changed as necessary while the vehicle is running will be described with reference to the flowcharts of FIGS. . Note that the processing illustrated in FIGS. 6 to 8 is started at regular intervals of, for example, 10 msec.

  According to FIG. 6, first, in step S1, the camera device constituting the obstacle recognition device 9 captures and captures a camera image within a predetermined distance range (several meters to several tens of meters) ahead of the vehicle, and in step S2. The obstacle recognition device 9 detects an obstacle in the vehicle traveling direction included in the camera image.

  At this time, as shown in FIG. 7, the obstacle recognizing device 9 first binarizes the camera image (step S11), and extracts a moving object included in the camera image (step S12). Here, for example, when the camera image is an RGB image, a portion that moves differently in the traveling direction of the vehicle is recognized as a moving object. When a far-infrared camera is provided as a configuration for detecting a moving object, a person can be extracted as a moving object if the luminance value of the infrared image captured by the far-infrared camera is about the body temperature of the person.

  Next, in step S13, the obstacle recognizing device 9 matches template data (binarized data) of a moving object such as a person previously stored in the database with the moving object extracted in step S12. Calculate the matching rate. Here, in order to reduce the storage capacity, the template is composed of feature point data representing the characteristics of all obstacles such as people, other vehicles, and stones, and a plurality of templates are stored in the database. For example, a person template is data in which the aspect ratio is set to be equivalent to that of a person, and the matching ratio is high when the aspect ratio and the aspect ratio of the moving object extracted in step S12 are substantially the same. .

  Next, in step S14, the obstacle recognizing device 9 determines whether or not the matching rate calculated in step S13 is equal to or lower than a preset matching threshold value. A template is searched and the processes in steps S13 and S14 are repeated. Then, when there are no templates to be newly searched in the database, the process proceeds from step S17 to step S18, and an obstacle finding indicating whether or not it is predicted that the vehicle is likely to be required to operate the brake is detected. The value of the flag is set to “OFF”, and the process proceeds to step S3 in FIG. At this time, the obstacle recognizing device 9 includes a counter that counts the number of times the matching calculation has been performed in step S13, and if the value of the counter matches the number of templates stored in the database, the step The process proceeds from S17 to step S18.

  On the other hand, if the obstacle recognition device 9 determines in step S14 that the matching rate calculated in step S13 is not less than or equal to the matching threshold, the obstacle detection flag value is set to “ON” in step S15. In step S16, the obstacle distance information is created by measuring the relative distance to the moving object for which the high matching rate is calculated in step S14, and the process proceeds to step S3 in FIG. The process of measuring the relative distance to the moving object may be a technique using the difference between the light emission time and the light incident time using laser radar or pulsed light. As shown in FIG. It may be measured that the relative distance to the vehicle is closer as the area occupied by the object is larger, the relative distance may be obtained from the vertical position of the moving object in the camera image, and the two installed at the right and left ends of the vehicle You may detect a relative distance using a parallax from a camera. Such a function of performing the process of step S2 in FIG. 6 (steps S11 to S16 of FIG. 7) constitutes a brake operation prediction unit.

  Next, in step S3 in FIG. 6, the ECU 1 determines whether or not the value of the obstacle detection flag set in the process in step S2 is “ON”. If the value of the obstacle detection flag is “ON”, in step S4, sudden braking predictive control is performed to change the damping coefficient C1 to the damping coefficient Cx, and the shock absorber 3 is attenuated in step S6. Change power. After the damping force of the shock absorber 3 is changed in step S6, the change of the damping force of the shock absorber 3 is caused by the on-spring vibration force and spring detected by the on-spring up / down G sensor 4 and the below-spring up / down G sensor 5. The damping force of the shock absorber 3 can be continuously updated by appearing as feedback to the lower vibration force and repeating steps S1 to S6.

  On the other hand, if the value of the obstacle detection flag is not “ON”, in step S5, normal damping force control for controlling the shock absorber 3 is performed so as to obtain a preset damping coefficient C1. Exit.

  As shown in FIG. 8, the sudden braking prediction control in step S4 detects the current vehicle speed from the sensor signal from the vehicle speed sensor 7 by the sudden braking prediction device 24 of the ECU 1 in step S21, and in step S22, The relative distance from the obstacle measured in step S16 in FIG. 7 is acquired. Here, the vehicle speed calculation in step S21 may be calculated from image data captured by the vehicle speed sensor 7, or may be calculated from speed pulse data from a chassis control system such as ABS (Anti-lock Brake System).

  In the next step S23 and step S24, processing for determining a correction value for correcting the damping coefficient C1 is performed based on the vehicle speed, the relative distance to the obstacle, and the wheel load. In step S23 and step S24, the sudden braking prediction device 24 as shown in FIG. 10 calculates a correction value based on the vehicle speed and the relative distance to the obstacle with reference to the damping force correction map of FIG. The correction value is corrected with reference to the wheel load correction table of FIG. As shown in FIG. 10, the sudden braking prediction device 24 includes a damping force correction map calculation unit 41 that calculates a correction value using a damping force correction map, and a correction value that is corrected using a wheel load correction table. A wheel load correction table calculation unit 42 that calculates a value and a contour correction unit 43 that corrects a correction value based on the wheel load are provided.

  In step S23, the damping force correction map calculation unit 41 of the sudden braking prediction device 24 refers to the damping force correction map of FIG. 11 based on the vehicle speed detected in step S21 and the relative distance to the obstacle acquired in step S22. To determine the damping force correction value.

  For example, the damping force correction map has a configuration in which the damping force correction value is increased as the distance is shorter. When the vehicle speed is V1, the correction value can be set to the highest value, and the vehicle speed is decreased to V2 and V3. The correction value is set lower than that at V1. Since such a correction value is set higher as the vehicle speed is higher and the relative distance to the obstacle is closer, it is synonymous with a value that predicts the possibility of a brake operation by the driver of the vehicle. That is, the higher the vehicle speed and the shorter the relative distance to the obstacle, the higher the possibility that the brake operation will be performed, and the higher the correction value. Thereby, the attenuation coefficient Cx which is a value higher than the predetermined attenuation coefficient C1 can be set.

  In the next step S24, the wheel load correction table calculation unit 42 of the sudden braking prediction device 24 corrects the correction value obtained based on the vehicle speed and the relative distance to the obstacle based on the front wheel load. Calculate the value. At this time, the wheel load correction table calculation unit 42 detects the sensor signal from the steering angle sensor 6 and determines that the front wheel load increases from the steady value as the current steering angle and speed increase. The wheel load correction value is obtained from the wheel load correction table shown in FIG. This wheel load correction table is set so that the wheel load correction value is set higher as the front wheel load increase amount increases.

  As shown in FIG. 13, the larger the front wheel load increase, the greater the amount of center of gravity movement forward of the vehicle, and the amount of center of gravity movement increases. That is, as shown in FIG. 2, the wheel load correction value is a value for increasing the maximum tire force as much as possible in order to suppress a decrease in the maximum tire force when the wheel load becomes too large.

  Then, the contour correction unit 43 multiplies the damping force correction value calculated by the damping force correction map calculation unit 41 in step S23 and the wheel load correction value, from the sudden braking prediction device 24 to the adder 31 of the feedback control unit 21. A correction value to be supplied to is calculated. Thereafter, the vehicle control device advances the processing to step S6 in FIG. 6 to obtain an attenuation coefficient C obtained by adding the correction value and the attenuation coefficient C1 by the adder 31, and uses the attenuation coefficient C to determine the damping force calculation unit 32. The damping coefficient Cx is obtained by the above and supplied to the actuator 2. As a result, the actuator 2 starts increasing the damping force of the shock absorber 3 and increases the damping force of the shock absorber 3 before the brake operation is performed. Such step S3 to step S6 and step S21 to step S24 in FIG. 6 constitute a damping force control means.

  In the vehicle control device that performs such processing, for example, as shown by a solid line in FIG. 14, when an obstacle such as a person is detected in the traveling direction of the vehicle at time t <b> 1, the driver starts the brake operation and brake hydraulic pressure Prior to time t2 when the vehicle rises (FIG. 14 (a)), the actuator 2 is controlled so as to start increasing the damping force of the shock absorber 3 for the front wheels. Thereby, as shown in FIG. 14 (e), the damping force Fc by the shock absorber 3 is gradually increased from the time t1 onward by increasing the damping coefficient Cx, and at the time t2 when the brake operation is actually performed, A state in which the damping force Fc is already high can be achieved. Here, the shock absorber 3 for which the damping coefficient Cx is increased to increase the damping force Fc may be any of the left and right shock absorbers 3RF and 3LF on the front wheels.

  When the brake operation is actually performed, the brake operation is detected by the ECU 1 based on a signal from the stop lamp switch 8, and the damping force of the shock absorber 3 is further increased. Then, as shown in FIG.14 (b), the load of a front wheel becomes high and the load of a rear wheel becomes high conversely. When the front wheel load increases and the rear wheel load decreases, as shown in FIG. 14C, the front wheel braking force and the rear wheel have a force relationship that the braking force of the front wheel is higher than the braking force of the rear wheel. The braking force increases. Further, as shown in FIG. 14 (d), when the front wheel load increases, the stroke amount of the suspension changes in a contracting direction, and conversely, when the rear wheel load decreases, the suspension stroke amount changes in a extending direction. .

  Then, at time t4 when the brake operation is performed from time t2 and the maximum brake hydraulic pressure that becomes the braking limit is generated (FIG. 14A), the front wheel braking force is the maximum value (FIG. 2C) as shown in FIG. 14), and the front wheel damping force of the shock absorber can be increased as shown in FIG. 14 (d).

  As a result, it is possible to suppress the nose dive state in which the vehicle is tilted forward by the front wheel suspension being significantly contracted, and to maintain the riding comfort when the brake operation is performed.

  On the other hand, as a comparative example for the vehicle control device to which the present invention is applied, each characteristic when the damping force by the shock absorber starts to be increased from time t2 when the brake operation is actually performed is indicated by a dotted line in FIG. . According to this comparative example, when the damping force by the shock absorber starts to increase from time t2, the damping force of the shock absorber is lower than that of the solid line, so at time t4 when the maximum brake hydraulic pressure is generated. Since the difference between the front wheel load and the rear wheel load is larger than the solid line, and the difference between the front wheel stroke amount and the rear wheel stroke amount is larger than the solid line, the vehicle is in a nose dive state. End up. Further, in this comparative example, the front wheel load becomes too large and the rear wheel load becomes too small, so that it is far from the wheel load that can generate the maximum tire force shown in FIG. However, at time t4 when the maximum brake hydraulic pressure is generated, the total braking force (vehicle braking force) of the front wheel braking force and the rear wheel braking force is lower than the total braking force of the solid line.

  Thus, according to the vehicle control device to which the present invention is applied, the front wheel load after the brake operation is actually performed by starting the control to increase the damping force of the shock absorber 3 before starting the brake operation. And the rear wheel load can be reduced, the braking performance can be improved as shown in FIG. 14C, and the vehicle stability can be maintained by reducing the change in the front wheel stroke amount and the rear wheel stroke amount. . As a result, even when the steering operation is performed when the maximum brake hydraulic pressure is generated, the steering operation can be transmitted to the tire to improve the emergency avoidance performance of the vehicle.

  As described above in detail, according to the vehicle control device to which the present invention is applied, when the possibility that the brake operation is performed is predicted and the possibility that the brake operation is performed is predicted to be high, Before the brake operation is performed, the control of the actuator 2 can be started so as to generate a high damping force Fc by setting a damping coefficient Cx higher than the normal damping coefficient C1, so that the delay of the damping force at the time of sudden braking is increased. Thus, the vehicle stability can be improved when sudden braking is required to improve the ride comfort, and further, the braking performance and emergency avoidance performance of the vehicle can be improved. That is, it is possible to achieve both ride comfort against vehicle vibration and vehicle response in an emergency.

  Further, according to this vehicle control device, when predicting a brake operation, the relative distance to an obstacle is detected, and a higher damping force is generated as the relative distance is shorter. Even when the vehicle is suddenly braked to avoid a vehicle or the like, high driving performance can be provided.

  Furthermore, according to this vehicle control device, when the brake operation is predicted, the vehicle speed is detected, and the higher the speed, the higher the damping force is generated. Therefore, the vehicle speed is high and the degree of nose dive is high. Even in this case, the degree of the nose dive can be suppressed.

  Furthermore, according to this vehicle control device, when changing the damping coefficient C1 to the damping coefficient Cx, the correction value for obtaining the damping coefficient Cx can be corrected so as to generate a higher damping force as the wheel load is higher. It can be suppressed that the difference between the load and the rear wheel load increases and the degree of nose dive increases and the braking performance decreases.

  Furthermore, according to this vehicle control device, the damping coefficient Cx for determining the damping force by the shock absorber 3 of the vehicle is increased for at least one of the right front wheel and the left front wheel, and the damping force of the shock absorber 3 is increased. Therefore, an increase in front wheel load and a front wheel stroke amount can be suppressed, and high vehicle stability and braking performance can be exhibited.

  The above-described embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and various modifications can be made depending on the design and the like as long as the technical idea according to the present invention is not deviated from this embodiment. Of course, it is possible to change.

It is a block diagram which shows the structure of the vehicle control apparatus to which this invention is applied. It is a figure which shows the relationship between wheel load and the maximum tire force. (A) is a figure for demonstrating skyhook theory, (B) is a figure for demonstrating controlling the damping force of a shock absorber. It is a block diagram which shows the structure which calculates | requires a damping coefficient in order to make the damping force of a shock absorber high in the vehicle control apparatus to which this invention is applied. In the vehicle control apparatus to which the present invention is applied, it is a block diagram showing a configuration for obtaining a damping coefficient for correcting a normal damping coefficient and increasing a damping force of a shock absorber. It is a flowchart which shows the process sequence which changes the damping force of a shock absorber with the vehicle control apparatus to which this invention is applied. It is a flowchart which shows the process sequence of an obstacle recognition control process. It is a flowchart which shows the process sequence of sudden braking prediction control. It is a figure which shows the relationship between the area of the moving object in a camera image, and the relative distance with an obstruction. It is a block diagram which shows the structure which correct | amends the correction value based on a vehicle speed and the relative distance with an obstruction by wheel load. It is a figure which shows the damping force correction map which determines a correction value with the relative distance of a vehicle speed and an obstruction. It is a figure which shows the wheel load correction table which determines a wheel load correction value from the front wheel load increase amount. It is a figure which shows the relationship between front-wheel load increase amount and a gravity center movement amount. It is a figure for demonstrating operation | movement of the vehicle provided with the vehicle control apparatus to which this invention is applied, and a comparative example, (a) is brake hydraulic pressure, (b) is front-wheel load and rear-wheel load, (c) is Front wheel braking force and rear wheel braking force, (d) is the front wheel stroke amount and rear wheel stroke amount, and (e) is the damping force of the shock absorber.

Explanation of symbols

1 ECU
2 Actuator 3 Shock absorber 4 Vertical G sensor 5 Vertical G sensor 6 Steering angle sensor 7 Vehicle speed sensor 8 Stop lamp switch 9 Obstacle recognition device 11 Damping force control device 21 Feedback control unit 21 Control unit 22 and 23 Integrator 24 Rapid braking prediction Device 31 Adder 32 Damping force calculation unit 41 Damping force correction map calculation unit 42 Wheel load correction table calculation unit 43 Contour correction unit

Claims (6)

In a vehicle damping force control apparatus for controlling an actuator for adjusting a damping force generated by a shock absorber that attenuates vibration applied to a vehicle,
Brake operation prediction means for predicting the possibility of brake operation,
When it is predicted that the brake operation is not performed by the brake operation prediction unit, the actuator is controlled so as to generate a predetermined damping force, and the brake operation is likely to be performed by the brake operation prediction unit. A damping force control means for starting control of the actuator so as to generate a damping force higher than the predetermined damping force before the brake operation is performed. A damping force control device for a vehicle. The brake operation prediction unit includes a distance detection unit that detects a distance from an obstacle existing in the traveling direction of the vehicle, and the shorter the distance between the vehicle and the obstacle detected by the distance detection unit, the shorter the brake Anticipating that the action is likely to happen,
The damping force control means generates a damping force higher than the predetermined damping force when the distance between the vehicle and the obstacle detected by the distance detecting means is short. The damping force control apparatus for vehicles as described. The brake operation prediction means includes speed detection means for detecting the speed of the vehicle, predicts that the higher the speed detected by the speed detection means, the higher the possibility that the brake operation will be performed,
The vehicular damping force control device according to claim 1, wherein the damping force control means generates a damping force higher than the predetermined damping force when the speed detected by the speed detecting means is high. .   The damping force control means includes wheel load detection means for detecting the wheel load of the vehicle, and the higher the wheel load detected by the wheel load detection means, the higher the damping force higher than the predetermined damping force. The vehicular damping force control device according to any one of claims 1 to 3, wherein the vehicular damping force control device is corrected as follows.   The damping force control means increases a damping coefficient of the shock absorber by increasing a damping coefficient for determining a damping force by the shock absorber for at least one of the right front wheel and the left front wheel. The vehicular damping force control device according to any one of claims 1 to 4. In a vehicle damping force control method for controlling an actuator for adjusting a damping force generated by a shock absorber that attenuates vibration applied to a vehicle,
Predict the possibility of brake operation,
If it is predicted that the brake operation will not be performed by the brake operation prediction means, the actuator is controlled so as to generate a predetermined damping force,
When it is predicted that the brake operation predicting unit is likely to perform a brake operation, the actuator is configured to generate a damping force higher than the predetermined damping force before the brake operation is performed. The vehicle damping force control method is characterized by starting control of the vehicle.

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