Vehicle control device and vehicle control system

Abstract

An ECU of the present invention comprises: an attitude stability control unit that determines a command value for controlling a variable damper, in accordance with a vehicle attitude change that has been input; a ride quality control unit that determines a command value for controlling the variable damper, in accordance with a sprung vibration of the vehicle that has been input; and a command value calculation unit that determines a command value for the variable damper on the basis of both of the command values from the attitude stability control unit and the ride quality control unit. The command value calculation unit, when a value indicating the attitude change of the vehicle is greater than or equal to a predetermined value, and a value indicating the sprung vibration in a sprung resonant frequency band is greater than a predetermined value, gives priority to the command value of the ride quality control unit.

Description

[Technical field]

[0001] The present disclosure relates to a vehicle control device and a vehicle control system that controls an actuator that changes a force that suppresses relative displacement between a vehicle body and a wheel. [Background technology]

[0002] Patent Document 1 discloses a control device that uses a control dead zone to prevent deterioration of ride comfort due to high-frequency input from the road surface, while hastening the convergence of vibrations at the time of large vibration input, thereby suppressing the feeling of bounciness. Patent Document 1 also discloses that the provision of a control dead zone improves the deterioration of vibration damping performance at the initial stage of occurrence of vehicle vertical behavior, and ensures posture stability by suppressing vehicle vertical behavior with a sufficiently high damping force even for large vehicle vertical behavior such as when traveling on an undulating road surface, without deteriorating ride comfort during normal driving. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-168329 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the control device disclosed in Patent Document 1, when a vehicle is turned, braked, or driven on an undulating road surface, the input from the road surface falls within a predetermined range, and the vehicle attitude change also falls within a predetermined range. If attitude stability control is selected at this time, there is a risk that vibration control performance will deteriorate. [Means for solving the problem]

[0005] An object of the present invention is to provide a vehicle control device and a vehicle control system capable of achieving both a comfortable ride and posture stability of the vehicle and improving vibration damping performance.

[0006] Books One embodiment of the invention is a vehicle control device that controls an actuator that is provided between a vehicle body and wheels and changes a force that suppresses relative displacement between the vehicle body and the wheels, and has an attitude stability control unit that determines a command value to control the actuator in response to an input change in vehicle attitude, a ride comfort control unit that determines a command value to control the actuator in response to an input sprung vibration of the vehicle, and a command value calculation unit that determines a command value for the actuator based on the command values ​​of both the attitude stability control unit and the ride comfort control unit, wherein when a value indicating the change in vehicle attitude is greater than or equal to a predetermined value and a value indicating the sprung vibration in the sprung resonant frequency band is greater than a predetermined value, the command value calculation unit prioritizes the command value of the attitude stability control unit by multiplying the command value of the ride comfort control unit by an index that decreases in response to an increase in the sprung acceleration of the vehicle.

[0007] Books A vehicle control system according to one embodiment of the invention comprises a force generating mechanism that adjusts the force between the vehicle body and wheels, a sprung state detection unit that detects or estimates sprung vibration, a vehicle attitude detection unit that detects or estimates a change in sprung attitude, and a controller that controls the force generating mechanism to weaken when a value indicating the change in sprung attitude and a value indicating the sprung vibration in the sprung resonant frequency band change from a state smaller than a predetermined value to a state larger than a predetermined value by multiplying the value indicating the change in sprung attitude by an exponent that decreases in accordance with an increase in the sprung vibration of the vehicle.

[0008] According to one embodiment of the present invention, it is possible to achieve both a comfortable ride and posture stability of a vehicle, and to improve vibration damping performance. [Brief description of the drawings]

[0009] [Figure 1] 1 is an overall configuration diagram showing a four-wheeled automobile to which an ECU according to an embodiment of the present invention is applied; [Diagram 2] FIG. 2 is a diagram showing a shock absorber mounted on the automobile in FIG. 1. [Diagram 3]2 is a block diagram showing a configuration of an ECU according to the first embodiment. FIG. [Figure 4] FIG. 2 is a block diagram showing a configuration of a vehicle model of an ECU. [Diagram 5] 2 is a block diagram showing a configuration of a vehicle behavior calculation unit of the ECU. [Figure 6] FIG. 4 is a block diagram showing a configuration of an anti-dive squat control unit in FIG. 3. [Figure 7] FIG. 4 is a block diagram showing a configuration of an anti-roll control unit in FIG. 3. [Figure 8] FIG. 4 is a block diagram showing the configuration of a wavy determination unit in FIG. 3. [Figure 9] 4 is a block diagram showing a configuration of a bump determination unit in FIG. 3. [Figure 10] FIG. 4 is a block diagram showing a configuration of a correction unit in FIG. 3. [Figure 11] FIG. 4 is a characteristic diagram showing changes over time in lateral acceleration, current value, roll rate, and sprung acceleration for the first embodiment and a comparative example. [Figure 12] FIG. 4 is a characteristic diagram showing frequency characteristics of sprung acceleration PSD for the first embodiment and a comparative example. [Figure 13] FIG. 11 is a block diagram showing a configuration of an ECU according to a second embodiment. [Figure 14] FIG. 11 is a block diagram showing a configuration of an ECU according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle control device and a vehicle control system according to an embodiment of the present invention will now be described in detail with reference to the accompanying drawings, taking as an example a case in which the vehicle control device and the vehicle control system are applied to a four-wheeled automobile.

[0011] Here, Fig. 1 to Fig. 10 show a first embodiment of the present invention. In Fig. 1 and Fig. 2, a vehicle body 1 constitutes the body of a vehicle. For example, left and right front wheels and left and right rear wheels (hereinafter collectively referred to as wheels 2) are provided on the underside of the vehicle body 1. These wheels 2 are constituted by including tires 3. The tires 3 act as springs that absorb small unevenness on the road surface. The vehicle body 1 and the wheels 2 constitute the vehicle.

[0012] The suspension device 4 is disposed between the vehicle body 1 and the wheels 2. The suspension device 4 is composed of a suspension spring 5 (hereinafter referred to as the spring 5) and a damping force adjustable shock absorber (hereinafter referred to as the variable damper 6) disposed in parallel with the spring 5 and disposed between the vehicle body 1 and the wheels 2.

[0013] The variable damper 6 of the suspension device 4 is an actuator that is provided between the body 1 and the wheels 2 of the vehicle and changes the force that suppresses the relative displacement between the body 1 and the wheels 2. The variable damper 6 also serves as a force generating mechanism that adjusts the force between the body 1 and the wheels 2 of the vehicle.

[0014] The variable damper 6 is configured using a hydraulic shock absorber with adjustable damping force. As shown in Fig. 2, the variable damper 6 is provided with a variable damping force actuator 7 consisting of a damping force adjustment valve and the like in order to continuously adjust the characteristics of the generated damping force (i.e., the damping force characteristics) from hard characteristics to soft characteristics. The variable damping force actuator 7 is a damping force adjustment unit that adjusts the damping force according to the supplied current (drive current).

[0015] The variable damping force actuator 7 does not necessarily have to be configured to continuously adjust the damping force characteristics, and may be configured to adjust the damping force in multiple stages, for example, two or more stages. The variable damper 6 may be of a pressure control type or a flow rate control type.

[0016] A CAN8 (controller area network) is a serial communication unit mounted on the vehicle body 1. The CAN8 performs multiplexed communication for vehicle use between a large number of electronic devices mounted on the vehicle and the ECU 21. The CAN8 transmits vehicle driving information by a CAN signal consisting of a serial signal. In this case, the vehicle driving information transmitted by the CAN8 includes, for example, yaw rate, steering angle, vehicle speed, longitudinal acceleration, brake fluid pressure, engine torque, etc.

[0017] The sprung acceleration sensor 9 is provided on the vehicle body 1 and detects vibration acceleration in the vertical direction on the vehicle body 1 side, which is the sprung side. The sprung acceleration sensor 9 constitutes a sprung state detection means that detects the vibration of the sprung body. The sprung state detection means is not limited to one that detects the vibration of the sprung body, and may be one that estimates the vibration of the sprung body based on vehicle driving information included in the CAN signal, for example.

[0018] For example, a total of three sprung acceleration sensors 9 are provided on the vehicle body 1. In this case, the sprung acceleration sensors 9 are attached to the vehicle body 1, for example, at positions near the upper ends of the variable dampers 6 on the left and right front wheel sides, and at a midpoint between the left and right rear wheels. The sprung acceleration sensors 9 detect vertical vibration acceleration on the vehicle body 1 side, which is the sprung side, and output the detection signal to the ECU 21.

[0019] The unsprung acceleration sensor 10 is provided on the wheel 2 side of the vehicle. A total of two unsprung acceleration sensors 10 are provided on the vehicle. Specifically, the unsprung acceleration sensors 10 are provided, for example, on the right front wheel and the left front wheel of the vehicle. The unsprung acceleration sensor 10 detects vertical vibration acceleration on the wheel 2 side, which is the unsprung side, and outputs a detection signal to the ECU 21.

[0020] The ECU 21 constitutes a vehicle control device that controls the suspension device 4. The ECU 21 controls the variable damper 6 that changes the force that suppresses the relative displacement between the vehicle body 1 and the wheels 2. Here, the ECU 21 is a controller that controls the force generated by the variable damper 6 (force generating mechanism). When the change in the sprung posture and the sprung vibration in the sprung resonance frequency band change from a state smaller than a predetermined value to a state larger than the predetermined value, the ECU 21 controls the variable damper 6 (force generating mechanism) to weaken the force generated.

[0021] The ECU 21 includes a processor 22 as a control unit. The processor 22 is configured by a microcomputer or the like. The ECU 21 includes a storage unit (not shown) including a ROM, a RAM, a non-volatile memory, and the like. The processor 22 controls the damping force of the variable damper 6 by executing a program stored in the storage unit.

[0022] 2, the input side of the ECU 21 is connected to the CAN 8, the sprung acceleration sensor 9, the unsprung acceleration sensor 10, etc., and the output side is connected to the damping force variable actuator 7 of the variable damper 6, etc. The processor 22 reads vehicle driving information from the CAN 8 via serial communication. The processor 22 reads the sprung acceleration sensor value (sprung acceleration) based on a detection signal from the sprung acceleration sensor 9. The processor 22 reads the unsprung acceleration sensor value (unsprung acceleration) based on a detection signal from the unsprung acceleration sensor 10.

[0023] 4 and 5, the ECU 21 includes a vehicle model 23 that estimates the lateral acceleration of the vehicle, and a vehicle behavior calculation unit 24 that calculates vehicle behavior such as the sprung speed and the relative speed. In addition, the ECU 21 includes a ride comfort control unit 25, a posture stability control unit 26, a swell / bump index calculation unit 30, and a command value calculation unit 34 (see FIG. 3), which will be described later.

[0024] As shown in Fig. 4, vehicle model 23 constitutes vehicle attitude detection means for estimating a change in sprung attitude. Vehicle model 23 estimates the lateral acceleration of the vehicle based on information (vehicle driving information) input from CAN 8. Specifically, vehicle model 23 estimates the lateral acceleration of the vehicle based on the steering angle and vehicle speed, and outputs the estimated lateral acceleration. The vehicle attitude detection means is not limited to vehicle model 23 that estimates a change in sprung attitude, and may be one that detects a change in sprung attitude (e.g., lateral acceleration, etc.).

[0025] As shown in FIG. 5, the vehicle behavior calculation unit 24 obtains the vehicle behavior based on the sprung acceleration input from the sprung acceleration sensor 9 and the unsprung acceleration input from the unsprung acceleration sensor 10. The vehicle behavior calculation unit 24 includes a subtractor 24A and integrators 24B and 24C. The sprung acceleration and the unsprung acceleration are input to the vehicle behavior calculation unit 24. The subtractor 24A subtracts the unsprung acceleration from the sprung acceleration to obtain the relative acceleration, which is the difference between them. The integrator 24B integrates the sprung acceleration to obtain the sprung velocity. The integrator 24C integrates the relative acceleration to obtain the relative velocity. The vehicle behavior calculation unit 24 outputs the sprung velocity and the relative velocity.

[0026] In the first embodiment, the vehicle behavior calculation unit 24 obtains the relative speed from the sprung acceleration and the unsprung acceleration. For example, if the suspension device 4 of each wheel is provided with a stroke sensor, the relative speed may be obtained based on the detection value of the stroke sensor. Also, the relative speed may be estimated based on information input from the CAN 8 (vehicle driving information).

[0027] As shown in FIG. 3, the ride comfort control unit 25 outputs a ride comfort control command for improving the ride comfort of the vehicle. The ride comfort control unit 25 controls the variable damper 6 according to the input sprung vibration of the vehicle. The sprung vibration of the vehicle includes, for example, the sprung speed and the relative speed. The sprung vibration of the vehicle may be directly detected by a sensor or the like, or may be estimated based on, for example, the sprung acceleration or the like. The ride comfort control unit 25 acquires the sprung speed and the relative speed (piston speed) between the sprung and unsprung parts from the vehicle behavior calculation unit 24. The ride comfort control unit 25 outputs a ride comfort control command based on the sprung speed and the relative speed of each wheel. At this time, the ride comfort control command is, for example, a control command value (current value) that becomes a command signal of a current to the damping force variable actuator 7. The ride comfort control unit 25 outputs a control command value for reducing the vertical vibration of the sprung part from the sprung speed and the relative speed based on, for example, the skyhook control law.

[0028] In the first embodiment, the ride comfort control unit 25 outputs a ride comfort control command based on skyhook control. However, the present invention is not limited to this, and the ride comfort control unit may output a ride comfort control command based on, for example, bilinear optimal control or H∞ control.

[0029] The attitude stability control unit 26 outputs an attitude stability control command for improving the attitude stability of the vehicle. The attitude stability control unit 26 receives the longitudinal acceleration transmitted from the CAN 8 and the estimated lateral acceleration output from the vehicle model 23. The attitude stability control unit 26 outputs an attitude stability control command based on the longitudinal acceleration and the estimated lateral acceleration. The attitude stability control unit 26 controls the variable damper 6 according to the input attitude change of the vehicle. When the attitude change of the vehicle becomes equal to or greater than a predetermined value, the attitude stability control unit 26 outputs an attitude stability control command such that the variable damper 6 has a hard characteristic. The attitude change of the vehicle occurs, for example, due to the turning, acceleration, or deceleration of the vehicle. The longitudinal acceleration and the estimated lateral acceleration are input to the attitude stability control unit 26. As shown in FIG. 3, the attitude stability control unit 26 includes an anti-dive squat control unit 27, an anti-roll control unit 28, and a control command selection unit 29.

[0030] The anti-dive squad control unit 27 outputs an anti-dive squad control command for suppressing the inclination of the vehicle in the longitudinal direction due to the acceleration or deceleration of the vehicle. The longitudinal acceleration is input to the anti-dive squad control unit 27. As shown in Fig. 6, the anti-dive squad control unit 27 includes a differentiator 27A, a front gain multiplication unit 27B, an inversion unit 27C, a rear gain multiplication unit 27D, a relative speed calculation unit 27E, and a damping force characteristic processing unit 27F.

[0031] Differentiator 27A differentiates the longitudinal acceleration to calculate a jerk in the longitudinal direction of the vehicle (longitudinal jerk). Front gain multiplication unit 27B multiplies the longitudinal jerk by a front gain, and outputs a target damping force on the front side. Rear gain multiplication unit 27D multiplies the longitudinal jerk multiplied by "-1" by inversion unit 27C by a rear gain, and outputs a target damping force on the rear side.

[0032] For example, when the derivative value of the longitudinal acceleration (longitudinal jerk) is negative, a dive behavior is predicted, so the front side needs to derive a target damping force that prepares for damper contraction, and the rear side needs to derive a target damping force that prepares for damper expansion. Taking this into consideration, the inversion unit 27C multiplies the longitudinal jerk by "-1" before multiplying it by the rear gain. That is, here, the extension side of the damper is made positive, and the compression side of the damper is made negative.

[0033] The relative velocity calculation unit 27E calculates the relative velocity from the longitudinal jerk. The damping force characteristic processing unit 27F is configured by, for example, a damping force map showing the relationship between the target damping force and the relative velocity and the command value (control command) to be output to the variable damper 6. The damping force characteristic processing unit 27F outputs a control command for controlling the front side variable damper 6 based on the front side target damping force and the relative velocity. The damping force characteristic processing unit 27F outputs a control command for controlling the rear side variable damper 6 based on the rear side target damping force and the relative velocity. These control commands are anti-dive squat control commands, and are, for example, control command values ​​(current values) that become command signals for current to the damping force variable actuator 7.

[0034] Anti-roll control section 28 outputs an anti-roll control command for suppressing the roll behavior of the vehicle. The estimated lateral acceleration is input to anti-roll control section 28. As shown in Fig. 7, anti-roll control section 28 includes a differentiator 28A, a left wheel gain multiplication section 28B, an inverter section 28C, a right wheel gain multiplication section 28D, a gain multiplication section 28E, a pitch control processing section 28F, a relative speed calculation section 28G, an adder 28H, and a damping force characteristic processing section 28J.

[0035] Differentiator 28A differentiates the estimated lateral acceleration to calculate a jerk (lateral jerk) in the lateral direction (left-right direction) of the vehicle. Left wheel gain multiplication unit 28B multiplies the lateral jerk by the left wheel gain and outputs a target damping force for the left wheel. Right wheel gain multiplication unit 28D multiplies the lateral jerk multiplied by "-1" by inversion unit 28C by the right wheel gain and outputs a target damping force for the right wheel.

[0036] For example, if the derivative value of the estimated lateral acceleration (lateral jerk) is positive, the vehicle body is predicted to sink to the right wheel side, so the left wheel side needs to be prepared for the extension side of the damper, and the right wheel side needs to be prepared for the contraction side of the damper. Taking this into consideration, the inversion unit 28C multiplies the lateral jerk by "-1" before multiplying it by the right wheel gain.

[0037] The anti-roll control unit 28 expands on the basic concept of G-vectoring for improving driving performance, "controlling longitudinal movement in accordance with lateral movement," and controls pitch movement in accordance with lateral movement. To this end, the gain multiplication unit 28E multiplies the lateral jerk by a gain. The pitch control processing unit 28F derives a target damping force for pitch control that meets the expanded concept of G-vectoring, based on the lateral jerk multiplied by the gain.

[0038] Relative speed calculation unit 28G calculates the relative speed from the lateral jerk. Adder 28H adds the target damping force on the left wheel side for pitch control to the target damping force on the left wheel side for roll suppression, and outputs the target damping force on the left wheel side for controlling roll and pitch. Adder 28H adds the target damping force on the right wheel side for pitch control to the target damping force on the right wheel side for roll suppression, and outputs the target damping force on the right wheel side for controlling roll and pitch.

[0039] The damping force characteristic processing unit 28J is configured by, for example, a damping force map indicating the relationship between the target damping force and relative speed and the command value (control command) to be output to the variable damper 6. The damping force characteristic processing unit 28J outputs a control command for controlling the variable damper 6 on the left wheel side based on the target damping force and relative speed on the left wheel side. The damping force characteristic processing unit 28J outputs a control command for controlling the variable damper 6 on the right wheel side based on the target damping force and relative speed on the right wheel side. These control commands are anti-roll control commands, and are, for example, control command values ​​(current values) that become a command signal for a current to the damping force variable actuator 7.

[0040] As shown in Fig. 3, an anti-dive squad control command and an anti-roll control command are input to the control command selection unit 29. The control command selection unit 29 compares the anti-dive squad control command and the anti-roll control command, and selects the control command with the larger value. The control command selection unit 29 outputs the selected control command as an attitude stability control command.

[0041] The swell / bump index calculation unit 30 determines whether or not vibration is occurring due to a road surface that swells in the vertical direction (hereinafter referred to as an undulating road) or a road surface that causes bumpy vibration (hereinafter referred to as a bumpy road surface) based on the sprung acceleration. The swell / bump index calculation unit 30 includes a swell determination unit 31, a bump determination unit 32, and a maximum value selection unit 33.

[0042] As shown in Fig. 8, the swell determination unit 31 includes a band pass filter 31A (hereinafter referred to as BPF 31A) and a peak value holding unit 31B. The BPF 31A extracts vibration components due to an undulating road from the sprung acceleration. Specifically, the BPF 31A extracts vibration components in a frequency band (e.g., 0.5 to 1.5 Hz) including about 1 Hz characteristic of swell from frequency components of, for example, 3 Hz or less contained in the sprung acceleration. When the vibration components due to swell are extracted from the BPF 31A, the peak value holding unit 31B holds the maximum value thereof and outputs it as an undulating road index.

[0043] As shown in Fig. 9, the bump determination unit 32 includes a band pass filter 32A (hereinafter, referred to as BPF 32A) and a peak value holding unit 32B. The BPF 32A extracts a vibration component (bump vibration) caused by a bumpy road surface from the sprung acceleration. Specifically, the BPF 32A extracts a vibration component in a frequency band (e.g., 3 to 7 Hz) of the bump vibration included in the sprung acceleration. When the vibration component of the bump vibration is extracted from the BPF 32A, the peak value holding unit 32B holds the maximum value thereof and outputs it as a bump index.

[0044] As shown in FIG. 3, a maximum value selection unit 33 compares the undulating road index output from the undulating determination unit 31 with the bump index output from the bump determination unit 32, selects the larger index value, and outputs it as the undulating / bump index.

[0045] The command value calculation unit 34 determines a command value for the variable damper 6 (actuator) based on the command values ​​of both the posture stability control unit 26 and the ride comfort control unit 25. When the change in the vehicle posture is equal to or greater than a predetermined value and the vibration of the sprung mass in the sprung mass resonant frequency band is greater than a predetermined value, the command value calculation unit 34 prioritizes the command value of the ride comfort control unit 25. The command value calculation unit 34 includes a correction unit 35 and a control command selection unit 36.

[0046] The correction unit 35 weakens the command value (posture stability control command) of the posture stability control unit 26 so that the command value (ride comfort control command) of the ride comfort control unit 25 is given priority. As shown in Fig. 10, the correction unit 35 includes a conversion table 35A and a multiplier 35B.

[0047] Conversion table 35A converts the swell / bump index into a value between 0 and 1 to determine an output value. The output value is large when the swell / bump index is small, and is small when the swell / bump index is large. That is, as the swell / bump index increases, the output value decreases from 1 toward 0. The output value becomes an index for correcting the posture stability control command. Multiplier 35B multiplies this output value by the posture stability control command, and outputs a corrected posture stability control command.

[0048] The control command selection unit 36 ​​compares the ride comfort control command with the corrected attitude stability control command and selects the control command with the larger value. The control command selection unit 36 ​​outputs the selected control command as the final control command. Specifically, the control command selection unit 36 ​​selects the hard value between the ride comfort control command and the corrected attitude stability control command. At this time, the command value calculation unit 34 executes the same process for the control commands of each of the four wheels. A driving current based on the final control command is supplied to the damping force variable actuator 7 of the variable damper 6. As a result, the damping force of the variable damper 6 is controlled by the ECU 21.

[0049] The ECU 21 according to the first embodiment has the above-mentioned configuration, and its operation will now be described.

[0050] When vertical vibration occurs due to unevenness of the road surface while the vehicle is traveling, various vehicle driving information, sprung acceleration, unsprung acceleration, etc. are input to the ECU 21 from the CAN 8, the sprung acceleration sensor 9, and the unsprung acceleration sensor 10. At this time, the vehicle model 23 of the ECU 21 calculates an estimated lateral acceleration based on the steering angle and the vehicle speed. In addition, the vehicle behavior calculation unit 24 calculates the sprung velocity and the relative velocity based on the sprung acceleration and the unsprung acceleration.

[0051] The ride comfort control unit 25 of the ECU 21 outputs a ride comfort control command for improving the ride comfort of the vehicle based on the sprung velocity and the relative velocity. The attitude stability control unit 26 of the ECU 21 outputs an attitude stability control command for improving the attitude stability of the vehicle based on the estimated lateral acceleration and longitudinal acceleration. At this time, the attitude stability control command has a value that suppresses dive squat and roll.

[0052] Incidentally, when the vehicle is traveling on a road surface that is undulating in the vertical direction (undulating road) or on a road surface that causes bumps (3-7Hz) (bumpy road), for example, when the vehicle suddenly brakes, the anti-dive squat control unit 27 increases the rate of change in the longitudinal acceleration, i.e., the differential value of the longitudinal acceleration. This causes the anti-dive squat control command to remain high at the maximum command value that the system can output, which may deteriorate the damping performance against road bumps and bumps. Also, for example, when a lane change is made while traveling on an undulating road or bumpy road, the anti-roll control unit 28 increases the rate of change in the estimated lateral acceleration, i.e., the differential value of the estimated lateral acceleration. This causes the anti-roll control command to remain high at the maximum command value that the system can output, which may deteriorate the damping performance against road bumps and bumps.

[0053] Therefore, in the ECU 21 of this embodiment, an undulation determination unit 31 determines an undulation index, which is the degree of undulation of the road surface, based on the sprung acceleration, and a bump determination unit 32 determines a bump index, which is the level of bump vibration, based on the sprung acceleration. Then, a maximum value selection unit 33 outputs the larger value of the undulation index and the bump index as the undulation / bump index. A correction unit 35 of the ECU 21 corrects the posture stability control command based on the undulation / bump index.

[0054] More specifically, the undulation / bump index calculation unit 30 of the ECU 21 obtains an undulation index and a bump index based on the sprung acceleration. The undulation / bump index calculation unit 30 selects the larger value of the undulation index and the bump index. The undulation / bump index calculation unit 30 outputs the selected index as the undulation / bump index.

[0055] A command value calculation unit 34 calculates a command value for the variable damper 6 (actuator) based on the posture stability control command and the ride comfort control command. The command value calculation unit 34 has a correction unit 35 that weakens the posture stability control command so that the ride comfort control command takes precedence. The correction unit 35 multiplies the posture stability control command by the output value of a conversion table 35A that receives the swell / bump index as an input, and outputs a corrected posture stability control command. The conversion table 35A that receives the swell / bump index as an input reduces its output value as the swell / bump index increases. This allows the corrected posture stability control command to be kept low even if the posture stability control command remains high due to sudden braking or lane change while driving on a road surface that is undulating in the vertical direction.

[0056] The command value calculation unit 34 selects the control command having the larger value between the corrected attitude stability control command and the ride comfort control command, and outputs it as the final control command. As a result, when the vehicle attitude change is equal to or greater than a predetermined value and the sprung vibration in the sprung resonance frequency band is greater than a predetermined value, the command value calculation unit 34 prioritizes the ride comfort control command over the attitude stability control command. As a result, even if the attitude stability control command remains high due to sudden braking or lane changing while driving on a road surface that is undulating in the vertical direction, the vibration control performance against the road undulation can be maintained.

[0057] Next, in order to confirm the vibration damping effect of the ECU 21, a comparison was made between the vibration damping performance and the like of a feedback control based on the conventional skyhook control law as a control according to a comparative example and the control according to the first embodiment by simulating a vehicle. The simulation conditions were that the vehicle made two lane changes while traveling at 60 km / h on a triangular-wave-shaped road surface with continuous undulations in the vertical direction with a wavelength of 12 m and a peak-to-peak value of 80 mm.

[0058] The simulation results are shown in Fig. 11 and Fig. 12. As shown in Fig. 11, in the first embodiment, the roll rate indicating posture stability is maintained at the same level as in the comparative example, while the current value (control command value) can be prevented from remaining high. As a result, as shown in Fig. 12, in the first embodiment, it is possible to suppress bumpy vibrations (3 to 7 Hz) compared to the comparative example.

[0059] Thus, according to the first embodiment, the ECU 21 (vehicle control device) has an attitude stability control unit 26 that controls the variable damper 6 (actuator) in accordance with the inputted vehicle attitude change, a ride comfort control unit 25 that controls the variable damper 6 in accordance with the inputted vehicle sprung vibration, and a command value calculation unit 34 that determines a command value for the variable damper 6 based on the command values ​​of both the attitude stability control unit 26 and the ride comfort control unit 25.

[0060] Here, the processor 22 of the ECU 21 controls the variable damper 6 to weaken the force generated when the change in sprung posture and the sprung vibration in the sprung resonance frequency band change from a state smaller than a predetermined value to a state larger than the predetermined value. Specifically, the command value calculation unit 34 prioritizes the command value of the ride comfort control unit 25 when the change in vehicle posture is equal to or larger than a predetermined value and the sprung vibration in the sprung resonance frequency band is larger than a predetermined value. This makes it possible to prioritize the ride comfort control command even when the vehicle is turned, braked, or driven on an undulating road surface, for example, and improves vibration damping performance.

[0061] Moreover, the command value calculation unit 34 has a correction unit 35 that weakens the command value of the attitude stability control unit 26 so that the command value of the ride comfort control unit 25 is given priority. As a result, when the vehicle attitude change is equal to or greater than a predetermined value and the sprung vibration in the sprung resonance frequency band is greater than a predetermined value, the attitude stability control command can be set to a small value (software side command), and the ride comfort control command can be given priority.

[0062] Next, Fig. 1, Fig. 2 and Fig. 13 show a second embodiment of the present invention. The second embodiment is characterized in that it switches between ride comfort control and attitude stability control according to the level of turning and acceleration / deceleration in addition to the swell / bump index. In the second embodiment, the same components as those in the first embodiment are given the same reference numerals and their description is omitted.

[0063] The ECU 41 according to the second embodiment is configured in substantially the same manner as the ECU 21 according to the first embodiment. The ECU 41 constitutes a vehicle control device that controls the suspension device 4. The ECU 41 is a controller that controls the force generated by the variable damper 6 (force generating mechanism). As shown in FIG. 2, the ECU 41 includes a processor 42 as a control unit. The processor 42 is configured by a microcomputer or the like. The processor 42 controls the damping force of the variable damper 6 by executing a program stored in a storage unit (not shown). The input side of the ECU 41 is connected to the CAN 8, the sprung acceleration sensor 9, the unsprung acceleration sensor 10, etc., and the output side is connected to the variable damper 6, etc.

[0064] Like the ECU 21 according to the first embodiment, the ECU 41 includes a vehicle model 23 and a vehicle behavior calculation unit 24. In addition, the ECU 41 includes a ride comfort control unit 25, a posture stability control unit 26, a swell / stiffness index calculation unit 30, a turning / acceleration / deceleration index calculation unit 43, and a command value calculation unit 48 (see FIG. 13).

[0065] 13, the turning / acceleration / deceleration index calculation unit 43 includes a turning index calculation unit 44, a deceleration index calculation unit 45, an acceleration index calculation unit 46, and a multiplier 47. The turning / acceleration / deceleration index calculation unit 43 calculates a turning / acceleration / deceleration index S4.

[0066] The turning index calculation unit 44 calculates a turning index S1 according to the turning level based on the steering angle. The steering angle is input to the turning index calculation unit 44 through the CAN8. The turning index calculation unit 44 includes an absolute value calculation unit 44A and a conversion table 44B. The absolute value calculation unit 44A calculates the absolute value of the steering angle. The conversion table 44B converts the magnitude (absolute value) of the steering angle into a value between 0 and 1 to calculate the turning index S1. The turning index S1 becomes a large value (a value close to 1) when the absolute value of the steering angle is small, and becomes a small value (a value close to 0) when the absolute value of the steering angle is large. That is, as the absolute value of the steering angle increases, the turning index S1 decreases from 1 toward 0.

[0067] The deceleration index calculation unit 45 calculates a deceleration index S2 corresponding to the deceleration of the vehicle based on the brake fluid pressure. The brake fluid pressure is input to the deceleration index calculation unit 45 through the CAN 8. The deceleration index calculation unit 45 is configured with a conversion table. The conversion table of the deceleration index calculation unit 45 converts the brake fluid pressure into a value between 0 and 1 to obtain the deceleration index S2. The deceleration index S2 becomes a large value (close to 1) when the brake fluid pressure is small (low), and becomes a small value (close to 0) when the brake fluid pressure is large (high). In other words, as the brake fluid pressure increases, the deceleration index S2 decreases from 1 toward 0.

[0068] The acceleration index calculation unit 46 calculates an acceleration index S3 corresponding to the acceleration of the vehicle based on the engine torque. The engine torque is input to the acceleration index calculation unit 46 through the CAN 8. The acceleration index calculation unit 46 includes a differentiator 46A and a conversion table 46B. The differentiator 46A differentiates the engine torque to obtain a differential value of the engine torque. The conversion table 46B converts the differential value of the engine torque to a value between 0 and 1 to obtain the acceleration index S3. The acceleration index S3 becomes a large value (a value close to 1) when the differential value of the engine torque is small, and becomes a small value (a value close to 0) when the differential value of the engine torque is large. That is, as the differential value of the engine torque increases, the acceleration index S3 decreases from 1 toward 0.

[0069] The multiplier 47 multiplies the turning index S1, the deceleration index S2, and the acceleration index S3 to output the turning / acceleration / deceleration index S4. Therefore, the turning / acceleration / deceleration index S4 becomes a large value (a value close to 1) when the turning index S1, the deceleration index S2, and the acceleration index S3 are all close to 1. On the other hand, the turning / acceleration / deceleration index S4 becomes 0 when any of the turning index S1, the deceleration index S2, and the acceleration index S3 is 0.

[0070] The command value calculation unit 48 determines a command value for the variable damper 6 (actuator) based on the command values ​​of both the posture stability control unit 26 and the ride comfort control unit 25. When the change in vehicle posture is equal to or greater than a predetermined value and the vibration of the sprung mass in the sprung mass resonant frequency band is greater than a predetermined value, the command value calculation unit 48 prioritizes the command value of the ride comfort control unit 25. The command value calculation unit 48 constitutes a correction unit. The command value calculation unit 48 weakens the command value of the posture stability control unit 26 (posture stability control command) so that the command value of the ride comfort control unit 25 (ride comfort control command) is prioritized.

[0071] The command value calculation section 48 includes a conversion table 48A, a maximum value selection section 48B, a subtractor 48C, multipliers 48D and 48E, and an adder 48F. The conversion table 48A converts the swell / bump index into a value between 0 and 1 to obtain a converted swell / bump index S5. The converted swell / bump index S5 has a small value when the swell / bump index is small, and a large value when the swell / bump index is large. That is, as the swell / bump index increases, the converted swell / bump index S5 increases from 0 toward 1. The maximum value selection section 48B compares the turning / acceleration / deceleration index S4 with the converted swell / bump index S5, selects the larger index, and outputs it as a selected index S6.

[0072] Subtractor 48C subtracts selection index S6 from 1. Multiplier 48D multiplies the output value of subtractor 48C by the attitude stability control command, and outputs a corrected attitude stability control command. Therefore, when selection index S6 is close to 0, the corrected attitude stability control command becomes a large value. On the other hand, when selection index S6 is close to 1, the corrected attitude stability control command becomes a small value.

[0073] The multiplier 48E multiplies the selection index S6 and the ride comfort control command, and outputs a corrected ride comfort control command. Therefore, the corrected ride comfort control command has a small value when the selection index S6 is close to 0. On the other hand, the corrected ride comfort control command has a large value when the selection index S6 is close to 1. The adder 48F adds the corrected posture stability control command and the corrected ride comfort control command, and outputs the result as a final control command.

[0074] Thus, the second embodiment thus configured can also obtain the same effects as the first embodiment. In addition, in the second embodiment, the ride comfort control and the posture stability control are switched depending on the turning / acceleration / deceleration level and the swell / bump index. For example, even if the swell / bump index is low, when "the turning level is small, i.e., the absolute value of the steering angle is small, therefore the turning index S1 is close to 1" and "the acceleration / deceleration level is small, i.e., the brake fluid pressure is small and the derivative of the engine torque is small, therefore the deceleration index S2 and the acceleration index S3 are both close to 1", it is not necessary to be concerned with posture stability, so it is desirable to prioritize the ride comfort control.

[0075] In this case, the turning / acceleration / deceleration index S4 is a value obtained by multiplying the turning index S1, the deceleration index S2, and the acceleration index S3, and therefore has a value close to 1. The selection index S6 is a value close to 1, since the larger index of the turning / acceleration / deceleration index S4 and the converted swell / stiffness index S5 is selected. At this time, the coefficient by which the output (ride comfort control command) of the ride comfort control unit 25 is multiplied is the selection index S6, which is a value close to 1. On the other hand, the coefficient by which the output (posture stability control command) of the attitude stability control unit 26 is multiplied is a value obtained by subtracting the selection index S6 from 1, and therefore has a value close to 0. As a result, the ride comfort control is prioritized over the attitude stability control. Here, the steering angle, the brake fluid pressure, and the engine torque are obtained by transmission from, for example, the CAN8.

[0076] On the other hand, if the swell / bump index is low and the turning level or acceleration / deceleration level is large, it is desirable to give priority to attitude stability control in order to give priority to attitude stability.

[0077] In this case, any one of the turning index S1 related to the absolute value of the steering angle, the deceleration index S2 related to the brake fluid pressure, and the acceleration index S3 related to the differential of the engine torque becomes a value close to 0. Therefore, the turning / acceleration / deceleration index S4, which is the multiplication result of these three indexes, becomes a value close to 0. In addition, since the undulation / bump index is small, the converted undulation / bump index S5 based on the undulation / bump index also becomes a value close to 0. The selection index S6 is close to 0 because the larger index of the turning / acceleration / deceleration index S4 and the converted undulation / bump index S5 is selected. At this time, the coefficient by which the output (ride comfort control command) of the ride comfort control unit 25 is multiplied is the selection index S6, which is a value close to 0. On the other hand, the coefficient by which the output (posture stability control command) of the posture stability control unit 26 is multiplied is a value obtained by subtracting the selection index S6 from 1, which becomes a value close to 1. As a result, the posture stability control is prioritized over the ride comfort control.

[0078] Next, Fig. 1, Fig. 2 and Fig. 14 show a third embodiment of the present invention. The third embodiment is characterized in that, in a limit state, attitude stability control is maintained to ensure the stability of operation in order to avoid danger. In the third embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted.

[0079] The ECU 51 according to the third embodiment is configured in a manner substantially similar to the ECU 21 according to the first embodiment. The ECU 51 constitutes a vehicle control device that controls the suspension device 4. The ECU 51 is a controller that controls the force generated by the variable damper 6 (force generating mechanism). The ECU 51 includes a processor 52 as a control unit. The processor 52 is configured by a microcomputer or the like. The processor 52 controls the damping force of the variable damper 6 by executing a program stored in a storage unit (not shown). As shown in FIG. 2, the input side of the ECU 51 is connected to the CAN 8, the sprung acceleration sensor 9, the unsprung acceleration sensor 10, etc., and the output side is connected to the variable damper 6, etc.

[0080] Like the ECU 21 according to the first embodiment, the ECU 51 includes the vehicle model 23 and the vehicle behavior calculation unit 24. In addition, the ECU 51 includes a ride comfort control unit 25, an attitude stability control unit 26, a swell / stiffness index calculation unit 30, a limit index calculation unit 53, and a command value calculation unit 57 (see FIG. 14).

[0081] The limit index calculation unit 53 includes a vehicle model 54, a subtractor 55, and a peak value holding unit 56. The limit index calculation unit 53 receives the yaw rate, steering angle, and vehicle speed from the CAN 8. The vehicle model 54 estimates the behavior of the vehicle based on the steering angle and the vehicle speed. Specifically, the vehicle model 54 estimates the yaw rate of the vehicle based on the steering angle and the vehicle speed, and outputs the estimated yaw rate. The subtractor 55 subtracts the yaw rate acquired from the CAN 8 from the estimated yaw rate, and obtains a differential yaw rate, which is the difference between these. The peak value holding unit 56 holds, for example, the maximum value of the absolute value of the differential yaw rate, and outputs a limit index corresponding to this maximum value. The limit index calculation unit 53 outputs the limit index.

[0082] The command value calculation unit 57 determines a command value for the variable damper 6 (actuator) based on the command values ​​of both the posture stability control unit 26 and the ride comfort control unit 25. When the change in vehicle posture is equal to or greater than a predetermined value and the vibration of the sprung mass in the sprung mass resonant frequency band is greater than a predetermined value, the command value calculation unit 57 prioritizes the command value of the ride comfort control unit 25. The command value calculation unit 57 constitutes a correction unit. The command value calculation unit 57 weakens the command value of the posture stability control unit 26 (posture stability control command) so that the command value of the ride comfort control unit 25 (ride comfort control command) is prioritized.

[0083] The command value calculation unit 57 includes conversion tables 57A and 57C, multipliers 57B and 57D, and a control command selection unit 57E. The conversion table 57A converts the limit index into a value between 0 and 1 to obtain the damping coefficient. When the limit index is small, the damping coefficient becomes a large value (a value close to 1), and when the limit index is large, the damping coefficient becomes a small value (a value close to 0). That is, as the limit index increases, the damping coefficient decreases from 1 toward 0. The multiplier 57B multiplies the damping coefficient by the swell / bump index, and outputs the damped swell / bump index S10. Therefore, when the damping coefficient is close to 0, the damped swell / bump index S10 becomes a small value. When the damping coefficient is close to 1, the damped swell / bump index S10 becomes a large value.

[0084] The conversion table 57C converts the damped swell / bump index S10 into a value between 0 and 1 to obtain a converted index S11. The converted index S11 becomes a large value (close to 1) when the damped swell / bump index S10 is small, and becomes a small value (close to 0) when the damped swell / bump index S10 is large. That is, as the damped swell / bump index S10 becomes larger, the converted index S11 becomes smaller from 1 toward 0. The multiplier 57D multiplies the converted index S11 by the posture stability control command, and outputs a corrected posture stability control command. Therefore, the corrected posture stability control command becomes a small value when the converted index S11 becomes a value close to 0. The corrected posture stability control command becomes a large value when the converted index S11 becomes a value close to 1.

[0085] The control command selection unit 57E compares the ride comfort control command with the corrected attitude stability control command and selects the control command with the larger value. The control command selection unit 57E outputs the selected control command as the final control command. Specifically, the control command selection unit 57E selects the hard value between the ride comfort control command and the corrected attitude stability control command. At this time, the command value calculation unit 34 executes the same process for the control commands of each of the four wheels. A driving current based on the final control command is supplied to the damping force variable actuator 7 of the variable damper 6. As a result, the damping force of the variable damper 6 is controlled by the ECU 21 (processor 22).

[0086] Thus, the third embodiment configured as above can also obtain the same effects as the first embodiment. In the third embodiment, when the change in the vehicle's attitude exceeds a value that prioritizes attitude stability, the command value calculation unit 57 prioritizes the command value (attitude stability control command) of the attitude stability control unit 26 regardless of the sprung vibration. At this time, whether the change in the vehicle's attitude is a value that prioritizes attitude stability is determined based on whether the vehicle is in a limit state.

[0087] Also, in the limit state, the difference (differential yaw rate) between the estimated yaw rate estimated from the steering angle and the vehicle speed using the vehicle model 54 and the actual yaw rate transmitted from the CAN 8 becomes large. For this reason, in the third embodiment, the peak value of this differential yaw rate is held as the limit index. When the limit index is large, the damping coefficient, which is the output value of the conversion table 57A, becomes close to 0, and the damped swell / bump index S10, which is the multiplication value with the swell / bump index, becomes close to 0. As a result, the output value (converted index S11) of the conversion table 57C related to the damped swell / bump index S10 becomes close to 1. This converted index S11 is multiplied by the attitude stability control command. At this time, since the converted index S11 is close to 1, the output of the attitude stability control command is maintained. For this reason, when the vehicle is in the limit state, it is possible to give priority to the attitude stability control.

[0088] On the other hand, if the vehicle is not in the limit state, the difference between the yaw rate and the estimated yaw rate (difference yaw rate) becomes small. At this time, the limit index is 0 and the damping coefficient is 1. Therefore, the swell / bump index and the damped swell / bump index become equal, and if the swell / bump index is large, the output value (converted index S11) of the conversion table 57C related to the damped swell / bump index S10 becomes close to 0. Since this converted index S11 is multiplied by the output value (posture stability control command) of the posture stability control unit 26, the posture stability control is suppressed low as in the first embodiment. Therefore, priority is given to the ride comfort control that determines vibration excitation / damping according to the relative speed and calculates the control command. This improves the vibration damping performance.

[0089] In the above-described embodiments, the variable damper 6, which is an actuator (force generating mechanism), is used to configure a semi-active suspension. The present invention is not limited to this, and the actuator may configure an active suspension that generates a force in the vertical direction between the vehicle body and the wheels. Specifically, the actuator is configured by an electric actuator, a hydraulic actuator, or the like that generates a force in the expansion or contraction direction between the vehicle body and the wheels. In this case, the command value calculation unit of the ECU prioritizes the command value of the ride comfort control unit when the change in the vehicle's attitude is not equal to or greater than a predetermined value, the force generated by the actuator is saturated, and the vibration of the sprung mass in the sprung mass resonance frequency band is greater than a predetermined value. As a result, even when the vehicle is turned, braked, or driven on an undulating road, for example, the ride comfort control command can be prioritized, and vibration damping performance can be improved.

[0090] In each of the above embodiments, an example has been described in which the actuator (force generating mechanism) that generates an adjustable force between the vehicle body 1 and the wheels 2 is configured with a damping force adjustable variable damper 6. However, the present invention is not limited to this, and for example, the actuator may be configured with an air suspension, a stabilizer (kinesus), an electromagnetic suspension, etc., in addition to a hydraulic shock absorber.

[0091] In each of the above-described embodiments, the attitude stability control unit 26 outputs an attitude stability control command that takes into consideration both the anti-dive squad control command and the anti-roll control command. The present invention is not limited to this, and the attitude stability control unit may output an attitude stability control command that is either an anti-dive squad control command or an anti-roll control command. In other words, the attitude stability control command may be an anti-dive squad control command or an anti-roll control command. For this reason, the attitude stability control unit may be configured to omit either one of the anti-dive squad control unit or the anti-roll control unit.

[0092] In the above embodiments, the suspension system used in a four-wheeled vehicle has been described as an example. However, the present invention is not limited to this and can also be applied to, for example, two-wheeled or three-wheeled vehicles, or work vehicles and transport vehicles such as trucks and buses.

[0093] The above-described embodiments are merely examples, and partial replacement or combination of the configurations shown in different embodiments or modified examples is possible.

[0094] Next, as the vehicle control device and the vehicle control system included in the above embodiment, for example, the following aspects are considered.

[0095] In a first aspect, a vehicle control device is provided between a vehicle body and a wheel, and controls an actuator that changes a force suppressing a relative displacement between the vehicle body and the wheel, the vehicle control device having an attitude stability control unit that determines a command value for controlling the actuator in response to an inputted attitude change of the vehicle, a ride comfort control unit that determines a command value for controlling the actuator in response to an inputted sprung vibration of the vehicle, and a command value calculation unit that determines a command value for the actuator based on the command values ​​of both the attitude stability control unit and the ride comfort control unit, and the command value calculation unit prioritizes the command value of the ride comfort control unit when a value indicating the attitude change of the vehicle is equal to or greater than a predetermined value and a value indicating the sprung vibration in the sprung resonance frequency band is greater than a predetermined value. This makes it possible to prioritize the ride comfort control command, for example, even when the vehicle is turned, braked, or driven on an undulating road, thereby improving vibration control performance.

[0096] In a second aspect, in the first aspect, the command value calculation unit has a correction unit that weakens the command value of the posture stability control unit so that the command value of the ride comfort control unit is prioritized. Thereby, when the vehicle posture change is equal to or greater than a predetermined value and the sprung vibration in the sprung resonance frequency band is greater than a predetermined value, the posture stability control command can be made smaller and the ride comfort control command can be prioritized.

[0097] As a third aspect, in the first or second aspect, when a value indicating a change in the vehicle attitude exceeds a value that prioritizes attitude stability, the command value calculation unit prioritizes the command value of the attitude stability control unit regardless of sprung vibration. Therefore, when the vehicle is in a limit state, it is possible to prioritize attitude stability control.

[0098] As a fourth aspect, in any one of the first to third aspects, the actuator constitutes an active suspension that generates a vertical force between the vehicle body and the wheels, and the command value calculation unit prioritizes the command value of the ride comfort control unit when the value indicating the change in vehicle attitude is not equal to or greater than a predetermined value, the force generated by the actuator is saturated, and the value indicating the sprung vibration in the sprung resonance frequency band is greater than a predetermined value. This makes it possible to prioritize the ride comfort control command, for example, even when a vehicle equipped with an active suspension is turned, braked, or driven on an undulating road surface, thereby improving vibration control performance.

[0099] A vehicle control system according to a fifth aspect includes a force generating mechanism for adjusting the force between the vehicle body and the wheels, a sprung state detection unit for detecting or estimating sprung vibration, a vehicle attitude detection unit for detecting or estimating a change in the attitude of the sprung, and a controller for controlling the force generating mechanism to weaken when a value indicating the change in the attitude of the sprung and a value indicating the sprung vibration in the sprung resonant frequency band change from a state smaller than a predetermined value to a state larger than the predetermined value, thereby making it possible to improve vibration damping performance by weakening the force generated by the force generating mechanism even when the vehicle is turned, braked, or driven on an undulating road, for example.

[0100] The present invention is not limited to the above-described embodiment, but includes various modified examples. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to those including all of the configurations described. It is also possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

[0101] This application claims priority to Japanese Patent Application No. 2021-113253, filed on July 8, 2021. The entire disclosure of Japanese Patent Application No. 2021-113253, filed on July 8, 2021, including the specification, claims, drawings, and abstract, is hereby incorporated by reference in its entirety into this application. [Explanation of symbols]

[0102] 1: vehicle body, 2: wheels, 4: suspension device, 6: variable damper (damping force adjustable shock absorber, actuator, force generating mechanism), 7: variable damping force actuator, 8: CAN, 9: sprung acceleration sensor (sprung state detection means), 10: unsprung acceleration sensor, 21, 41, 51: ECU (vehicle control device, controller), 23: vehicle model (vehicle state detection means)

Claims

1. A vehicle control device that controls an actuator that is provided between a vehicle body and a wheel of a vehicle and changes a force that suppresses a relative displacement between the vehicle body and the wheel, an attitude stability control unit that determines a command value for controlling the actuator in response to an input change in attitude of the vehicle; a ride comfort control unit that determines a command value for controlling the actuator in response to the input sprung vibration of the vehicle; a command value calculation unit that calculates a command value for the actuator based on command values ​​of both the posture stability control unit and the ride comfort control unit, The vehicle control device, when a value indicating a change in vehicle posture is equal to or greater than a predetermined value and a value indicating sprung vibration in a sprung resonant frequency band is greater than a predetermined value, the command value calculation unit prioritizes the command value of the posture stability control unit by multiplying the command value of the posture stability control unit by an index that decreases in accordance with an increase in the sprung acceleration of the vehicle.

2. The command value calculation unit has a correction unit that weakens the command value of the posture stability control unit so that the command value of the ride comfort control unit is prioritized, The index is multiplied by the command value of the posture stability control unit by the correction unit. The vehicle control device according to claim 1.

3. The command value calculation unit prioritizes the command value of the posture stability control unit regardless of the sprung vibration when a value indicating a posture change of the vehicle exceeds a value giving priority to posture stability. The vehicle control device according to claim 1.

4. the actuator constitutes an active suspension that generates a force in a vertical direction between the vehicle body and the wheel, The command value calculation unit prioritizes the command value of the ride comfort control unit when the value indicating the change in vehicle attitude is not equal to or greater than a predetermined value, the force generated by the actuator is saturated, and the value indicating the sprung vibration in the sprung resonance frequency band is greater than a predetermined value. The vehicle control device according to claim 1.

5. A vehicle control system, comprising: a force generating mechanism for adjusting a force between a body and a wheel of the vehicle; a sprung state detection unit that detects or estimates sprung vibration; A vehicle attitude detection unit that detects or estimates a change in the attitude of a sprung mass; and a controller that controls the force generating mechanism to weaken when a value indicating a change in sprung posture and a value indicating sprung vibration in a sprung resonant frequency band change from smaller than a predetermined value to larger than the predetermined value by multiplying the value indicating the change in sprung posture by an exponent that decreases in accordance with an increase in the sprung vibration of the vehicle.

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