JP4735345B2 - Body posture control device - Google Patents

Description

  The present invention relates to a vehicle body attitude control device that controls the attitude of a vehicle body when the vehicle is turning.

An example of a vehicle body attitude control device that controls the attitude of the vehicle body when the vehicle is turning is described in Patent Document 1 below. This vehicle attitude control device is a damping force control device for four shock absorbers when the vehicle is provided with four shock absorbers capable of controlling damping force between the front, rear, left and right wheels and the corresponding part of the vehicle body. By controlling this, the damping force of these four shock absorbers is controlled to an appropriate magnitude, and the rolling of the vehicle body is appropriately suppressed. Specifically, assuming a first virtual shock absorber that generates a vertical damping force on the outer side in the width direction of the vehicle and a second virtual shock absorber that suppresses rolling of the vehicle body, it is as if the first and first 2 Controlling the damping force of the four shock absorbers corresponding to the four wheels as if the posture of the vehicle body is suppressed by the virtual shock absorber, The roll angle is suppressed to an appropriate size while keeping the center of gravity of the vehicle body low).
Japanese Patent No. 3509544

  However, in the vehicle body attitude control device according to the invention described in Patent Document 1, the pitch angle is not actively controlled. When the vehicle turns, rolling of the vehicle body occurs, and pitching also occurs with this rolling. For example, the left and right front wheels (front wheel or front wheel) may differ depending on the magnitude of the damping force between the left front wheel and left rear wheel (collectively referred to as the left wheel) and the right front wheel and right rear wheel (collectively referred to as the right wheel). A force for lifting the vehicle body, that is, a jack-up force, is generated on the left and right rear wheels (collectively referred to as rear wheels or rear wheels). This is because the damping force of the shock absorber is generally greater during contraction than during expansion. Further, the jackup force is also generated based on the lateral force acting between the road surface and the wheel and the suspension geometry. This jack-up force can be negative, but is usually positive. These jackup forces are often different between the front wheel side and the rear wheel side, and the front-rear direction distance from the center of gravity of the vehicle body to the front wheel and the front-rear direction distance to the rear wheel are often different. For this reason, the pitching torques around the center of gravity of the vehicle body on the front wheel side and the rear wheel side are not balanced, and pitching actually occurs in the vehicle body. In the vehicle body posture control device described in Patent Document 1, this pitching is not actively controlled, which may give the passenger a sense of incongruity or worsen the turning feeling.

  The uncomfortable feeling due to the pitching and the deterioration of the turning feeling are particularly clearly felt when the rolling is suppressed, but are also felt when the rolling is not suppressed. Therefore, the present invention has been made with an object of obtaining a vehicle body posture control device capable of reducing the uncomfortable feeling caused by the pitching and the deterioration of the turning feeling.

(A) a vehicle body; (b) four or more wheels on the front, rear, left and right; (c) a suspension disposed between the four or more wheels and the vehicle body; Controlling the posture of the vehicle body including a braking device that brakes at least some of the four or more wheels, and (e) a driving device that drives at least some of the four or more wheels. (A) a roll angle acquisition unit that acquires the roll angle of the vehicle body, and (b) a roll angle corresponding pitch that controls the pitch angle of the vehicle body according to the roll angle acquired by the roll angle acquisition unit. An angle control unit , and the roll angle-corresponding pitch angle control unit controls the longitudinal acceleration of the vehicle by controlling at least one of the braking device and the driving device, whereby the pitch of the vehicle body The roll angle obtained by the roll angle obtaining unit. It is solved by including a longitudinal acceleration-dependent pitch angle control unit that controls to a value corresponding to .

As described above, pitching may occur due to rolling when the vehicle turns. Due to this pitching, the posture of the vehicle body in the front-rear direction becomes inappropriate, the relationship between the roll angle size and the pitch angle size becomes inappropriate, or the phase of the roll angle change and the pitch angle change is out of phase. If it does so, the turning feeling of a vehicle will worsen. Therefore, in the present invention, the pitch angle is controlled according to the roll angle, thereby improving the ride comfort during turning.
Moreover, in the present invention, since the pitch angle is controlled by the pitch moment generated according to the longitudinal acceleration, the pitch angle can be controlled both in the transient turning state and in the steady turning state.
In general, when the vehicle turns, the vehicle body rolls outward with a relatively small roll angle, and when the vehicle is pitched slightly forward, it is said that the ride comfort is good, that is, the turning feeling is good. Yes. If the present invention is implemented in combination with appropriate roll control, this good feeling can be realized.
However, it is not indispensable to be controlled in a state satisfying the above conditions. The present invention also includes a mode in which the vehicle body is controlled to be kept in a neutral posture or slightly tilted backward, or the pitching posture is controlled to gradually change over time. Furthermore, although it is desirable that the present invention be implemented in combination with appropriate roll control, it is not essential. If the pitch angle is controlled so as to correspond to the roll angle actually generated, the turning feeling is improved.

Aspects of the Invention

  In the following, the invention that is claimed to be claimable in the present application (hereinafter referred to as “claimable invention”. The claimable invention is at least the “present invention” to the invention described in the claims. Some aspects of the present invention, including subordinate concept inventions of the present invention, superordinate concepts of the present invention, or inventions of different concepts) will be illustrated and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combinations of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

In each of the following items, the combination of the items (1) and (4) corresponds to claim 1, the item (5) in claim 2 , the item (6) in claim 3 , (7) corresponds to claim 4 , (8) corresponds to claim 5 , (9) corresponds to claim 6 , and (10) corresponds to claim 7 .

(1) A device for controlling the posture of a vehicle body supported by four or more wheels on the front, rear, left, and right via a suspension of a vehicle,
A roll angle acquisition unit for acquiring a roll angle of the vehicle body;
And a roll angle corresponding pitch angle control unit that controls the pitch angle of the vehicle body in accordance with the roll angle acquired by the roll angle acquisition unit.
(2) The roll angle-corresponding pitch angle control unit includes a fixed control unit that controls the pitch angle value so as to maintain a predetermined one-to-one relationship with the roll angle value. The vehicle body attitude control device according to item.
For example, a map or function representing the one-to-one relationship between the pitch angle and the roll angle is acquired by experiment or calculation, and stored in the storage unit of the control device, and the pitch angle is controlled based on them. By doing so, the pitch angle is controlled to a value corresponding to the roll angle on a one-to-one basis, and a good turning feeling can be obtained stably.
The pitch angle only needs to be changed while maintaining a one-to-one relationship with the roll angle, and the phase of the change need not necessarily match.
(3) The roll angle-corresponding pitch angle control unit includes a phase matching type control unit that controls the pitch angle so that the pitch angle increases or decreases as the roll angle increases or decreases and the phase of the change coincides ( The vehicle body attitude control device according to item 1) or (2).
As described above, if the phase of the change in the roll angle and the change in the pitch angle coincide with each other, a good turning feeling can be obtained, and the relationship between the roll angle and the pitch angle is uniquely handled. It is not essential. For example, the size relationship can be changed in accordance with the driving state, driving environment and driver's preference.
When this term is subordinate to the term (2), a mode including both a fixed control unit and a phase matching control unit and a mode in which the fixed control unit is also a phase matching control unit are included. In the former mode, the fixed control unit and the phase matching control unit can be selectively operated according to, for example, the driving state of the vehicle, the driving environment, the driver's preference, etc. Sometimes the other can be actuated.
(4) In addition to the vehicle body, the four or more wheels, and the suspension, the vehicle brakes at least a part of the four or more wheels, and the four or more wheels. A drive device that drives at least a part of the vehicle, and the roll angle-corresponding pitch angle control unit controls the longitudinal acceleration of the vehicle by controlling at least one of the braking device and the drive device. Any one of the items (1) to (3), including a longitudinal acceleration-dependent pitch angle control unit that controls to control the pitch angle of the vehicle body to a value corresponding to the roll angle acquired by the roll angle acquisition unit. The vehicle body posture control device described in 1.
In the vehicle body attitude control device of this section, the pitch angle of the vehicle body is controlled corresponding to the roll angle acquired by the roll angle acquisition unit by controlling the longitudinal acceleration of the vehicle. If at least some of the plurality of wheels are braked by the braking device, the product of the deceleration generated by braking, the mass of the vehicle, and the distance between the center of gravity of the vehicle and the road surface (center of gravity height) A pitch moment expressed by the following acts, and the posture of the vehicle body changes from the backward leaning side to the forward leaning side. When the vehicle body is in a neutral posture, it actually tilts forward, but when it tilts backward, it may only reduce the degree of backward tilt and not forward. In addition, forward tilt, neutral posture, and rearward tilt are independent of the slope of the road surface, and even when they are relative to an absolute horizontal plane, the posture parallel to the road surface is neutral and Including the case of tilting and tilting backward.
In addition, when it is necessary to change the vehicle body posture from the forward leaning side to the rearward leaning side and the deceleration control is already performed by the braking device, the vehicle body posture can be improved by reducing the deceleration. It can be changed from the tilt side to the back tilt side. Alternatively, the driving torque of the driving device is increased to accelerate the vehicle, and a pitch moment represented by the product of acceleration, the mass of the vehicle body and the height of the center of gravity acts on the vehicle body, and the posture of the vehicle body changes from the forward leaning side to the backward leaning side. It may be allowed to be made.
If the pitch angle is controlled by the pitch moment generated according to the longitudinal acceleration, the pitch angle can be controlled both in the transient turning state and in the steady turning state.
(5) The longitudinal acceleration-dependent pitch angle controller
A target pitch angle setting unit that sets a target pitch angle based on the roll angle acquired by the roll angle acquisition unit;
An actual pitch angle acquisition unit for acquiring an actual pitch angle of the vehicle body;
The vehicle body attitude control device according to (4), further including a longitudinal acceleration control unit that controls the longitudinal acceleration so that the actual pitch angle acquired by the actual pitch angle acquisition unit approaches the target pitch angle.
(6) The longitudinal acceleration control unit is
A brake for applying braking torque to the four or more wheels;
The vehicle body posture control device according to (5), further comprising: a brake control device that controls the longitudinal acceleration by controlling an acting force of the brake.
According to the characteristics of this section, the posture of the vehicle body in the front-rear direction can be changed from the backward leaning side to the forward leaning side by applying a brake or increasing the acting force. It can be changed from the tilt side to the back tilt side.
The brake includes a friction brake including a brake rotating body that rotates with the wheel, a friction member that is held by a non-rotating body, and a pressing device that presses the friction member against the rotating body, an engine, and an electric motor. And a transmission device that transmits the rotational torque of the drive source to a drive wheel that is at least a part of the four or more wheels, and the drive source and the transmission device serve as a rotational resistance applying device. This includes engine brakes and electric brakes that are used.
(7) The vehicle body posture control according to any one of (4) to (6), wherein the longitudinal acceleration-dependent pitch angle control unit includes a forward tilt control unit that controls the posture of the vehicle body to the forward tilt side from the neutral posture. apparatus.
(8) Further, a roll control unit that controls rolling of the vehicle body, and the pitch angle control unit corresponding to the roll angle controls the pitch angle so as to correspond to the roll angle controlled by the roll control unit ( The vehicle body attitude control device according to any one of items 4) to (7).
As described above, it is particularly easy to improve the turning feeling by controlling both the roll angle and the pitch angle.
The features of this section can also be adopted in the inventions according to the above items (1) to (3).
(9) The suspension includes a shock absorber capable of controlling a damping characteristic, and the roll control unit is based on a damping characteristic that controls rolling of the vehicle body by controlling the damping characteristic of the shock absorber. The vehicle body attitude control device according to item (8), including a roll control unit.
According to the feature of this section, the roll angle can be controlled using a shock absorber capable of controlling the damping characteristic, and the object can be achieved at low cost. However, because the damping characteristics of the shock absorber are used, the roll angle cannot be controlled if the steady turning state continues. However, the steady turning state rarely lasts for a long time when the vehicle actually travels, so that there is a sufficient profit.
(10) The suspension includes a shock absorber capable of controlling a damping characteristic, and the roll angle corresponding pitch angle control unit controls the damping characteristic of the shock absorber by controlling the damping characteristic of the shock absorber in a transient turning state of the vehicle. The vehicle body according to any one of (2) to (8), further including a damping characteristic-based pitch control unit that controls a pitch angle of the vehicle body, wherein the longitudinal acceleration-based pitch angle control unit operates in a steady turning state of the vehicle. Attitude control device.
In the case of using the damping characteristic-dependent pitch control unit, as in the case of using the damping characteristic-based roll control unit, if the steady turning state continues, the pitch angle cannot be controlled. Therefore, it is reasonable to control the pitch angle by the damping characteristic-dependent pitch control unit in the transient turning state, and to control the pitch angle by the longitudinal acceleration-dependent pitch angle control unit in the steady turning state. That is. In addition, if the longitudinal acceleration-dependent pitch angle control unit is operated, the traveling speed of the vehicle changes, so it is desirable that the pitch angle control by the longitudinal acceleration-dependent pitch angle control unit be as short as possible. Also in this respect, the combined use with the damping characteristic-based pitch control unit is desirable. In particular, when a friction brake is used as a braking device, the combined use is more desirable from the viewpoint of saving energy consumption.
(11) A vehicle body, four or more wheels on the front, rear, left and right, a suspension disposed between the wheels and the vehicle body, and a drive device that drives at least some of the four or more wheels; A vehicle body posture control device for controlling the posture of a vehicle body at the time of turning of a vehicle comprising a braking device for braking at least a part of the four or more wheels,
Pitching generated in the vehicle body due to centrifugal force acting on the vehicle body when the vehicle turns is controlled by controlling the longitudinal acceleration of the vehicle by controlling at least one of the driving device and the braking device. A vehicle body attitude control device including a longitudinal acceleration-dependent pitching control unit.
Centrifugal force acts on the vehicle body when the vehicle turns, and the vehicle body rolls. Pitching often occurs with the rolling. When this pitching deteriorates the riding comfort of the vehicle, it is desirable to control the pitching with a better riding comfort by the longitudinal acceleration-dependent pitching control unit.
The features described in each of the above items (1) to (10) are also applicable to the invention of this item.

  Hereinafter, embodiments of the claimable invention will be described with reference to the drawings. In addition to the following examples, the claimable invention can be practiced in various modifications based on the knowledge of those skilled in the art, including the aspects described in the above [Aspect of the Invention] section.

  1 and 2 show a vehicle body posture control device as an embodiment of the claimable invention. This attitude control device controls the rolling and pitching of the vehicle body 6 by controlling the damping force of the suspensions 4FL, 4FR, 4RL, 4RR of the left and right front wheels 2FL, 2FR and the left, right rear wheels 2RL, 2RR. A suspension electronic control unit (abbreviated as ECU) 10 and a brake ECU 20 that controls the pitching of the vehicle body by controlling the brake system 12 are included. When it is not necessary to distinguish the left and right front wheels 2FL and 2FR and the left and right rear wheels 2RL and 2RR and the suspensions 4FL, 4FR, 4RL and 4RR, they are referred to as a wheel 2 and a suspension 4, respectively. Further, the portions supported by the left and right front wheels 2FL and 2FR and the left and right rear wheels 2RL and 2RR via the suspensions 4FL, 4FR, 4RL and 4RR of the vehicle body are represented by 6FL, 6FR, 6RL and 6RR, respectively. When it is not necessary, the vehicle body 6 is collectively referred to.

  Each suspension 4 includes a shock absorber 28 and a suspension spring 30 (spring 30 and the spring 30) provided in parallel with each other between a wheel holding member 26 that holds each wheel 2 and each part (6FL, 6FR, 6RL, 6RR) of the vehicle body 6. Abbreviated). The shock absorber 28 includes a variable throttle mechanism 32 that can control a damping force, and a damping control actuator 34 of the variable throttle mechanism 32 is controlled by the suspension ECU 10. A vehicle height sensor 36 and a vertical acceleration sensor 38 are provided corresponding to each of the wheels 2. The vehicle height sensor 36 detects the relative position in the vertical direction between the wheel 2 and the vehicle body 6, and the vertical acceleration sensor 38 is provided in each part 6FL, 6FR, 6RL, 6RR corresponding to each wheel 2 of the vehicle body 6. The acceleration in the vertical direction of each part is detected.

  The vehicle height sensor 36 and the vertical acceleration sensor 38 are connected to the suspension ECU 10. The suspension ECU 10 is further provided with a vehicle speed detection device 46 for detecting the vehicle speed, which is the traveling speed of the vehicle, and the yaw rate of the vehicle body 6. A yaw rate sensor 48 and a lateral acceleration sensor 50 for detecting the lateral acceleration and the lateral acceleration, respectively, are also connected.

  As shown in FIG. 2, a hydraulic pressure control actuator 60 is connected to the brake ECU 20, and the hydraulic pressure control actuator 60 has an operation force that is a kind of operation amount of a brake pedal 62 as a brake operation member. In response to the hydraulic pressure supplied from the master cylinder 64 that generates hydraulic pressure or the hydraulic pressure source 66 that generates hydraulic pressure by power, hydraulic brakes 68FL provided for each of the wheels 2 are provided. Fluids of wheel cylinders 70FL, 70FR, 70RL, and 70RR (collectively referred to as wheel cylinders 70 when there is no need to distinguish) 68FR, 68RL, 68RR (collectively referred to as hydraulic brake 68 when it is not necessary to distinguish). Control pressure individually. Therefore, the power hydraulic pressure source 66 includes an accumulator that stores hydraulic fluid under pressure, and the hydraulic pressure control actuator 60 includes a pressure increase control valve and a pressure reduction control valve corresponding to each wheel cylinder 70. The power hydraulic pressure source 66 and the hydraulic pressure control actuator 60 are actually held in a common holding block and integrated. A wheel speed sensor 72 is provided corresponding to each wheel 2, and these wheel speed sensors 72 are connected to the brake ECU 20. The vehicle speed detection device 46 may be one that detects the vehicle speed as a relative speed between the vehicle body 6 and the road surface. In this embodiment, the four wheel 2 detected by the wheel speed sensor 72 is used. The vehicle speed is calculated based on the wheel speed.

  The posture control device suppresses rolling of the vehicle body 6 by damping force control of the suspension 4 and controls pitching caused by rolling by damping force control of the suspension 4 and braking control by the brake ECU 20. This pitching control is performed so that the pitch angle maintains a predetermined relationship with the roll angle suppressed by the damping force control.

First, the principle of roll suppression by damping force control will be described.
FIG. 3 shows a two-wheel model of an actual vehicle, in which a shock absorber 28 and a spring 30 are disposed in parallel between the vehicle body 6 and the left and right wheels 2, respectively. On the other hand, FIG. 4 shows a virtual two-wheel model for explaining the principle of rolling suppression. In this two-wheel model, only the spring 30 is disposed between the vehicle body 6 and the left and right wheels 2. A lift suppression shock absorber 104 that suppresses the lifting of the vehicle body 6 when the vehicle turns, and a roll suppression shock that suppresses the roll of the vehicle body 6 between the virtual wheel 102 that travels at the virtual position inside the turn and the vehicle body 6. An absorber 106 is provided. In this virtual vehicle model, an increase in vehicle height (indicated by an arrow U) corresponding to a wheel on the inner side of the turn (hereinafter referred to as an inner wheel and a wheel on the outer side of the turn is referred to as an outer wheel) 2 is suppressed. The rise of the vehicle body center of gravity O is suppressed, and the rolling of the vehicle body 6 (indicated by the arrow Q) is suppressed. Therefore, the maneuverability can be improved by adapting the actual vehicle model to the virtual model.

If the left turn is considered in the vehicle model of FIG. 3, the equation of motion of the vehicle body 6 in the vertical direction is expressed by the following equation (1).
M · Xbdd = K · Xin + K · Xout + Cin · Xind + Cout · Xoutd (1)
However,
M: Mass of the vehicle body K: Spring constants Cin and Cout of the spring 30: Damping coefficients of the inner and outer wheels Xbdd: Vertical acceleration Xin in the absolute space of the vehicle body 6, Xout: Strokes Xind and Xoutd of the inner and outer wheels : Stroke speed of inner and outer wheels The equation of motion around the vehicle longitudinal axis passing through the center of gravity O of the vehicle body 6 is expressed by the following equation (2).
Ir.theta.dd = W. (K.Xin-K.Xout + Cin.Xind-Cout.Xoutd) / 2 (2)
However,
Ir: Roll inertia moment θdd of the vehicle body 6: Angular acceleration around the vehicle longitudinal axis passing through the center of gravity O of the vehicle body W: Wheel tread of the left and right wheels

On the other hand, in the virtual vehicle model of FIG. 4, the equation of motion of the vehicle body 6 in the vertical direction and the equation of motion around the vehicle longitudinal axis passing through the center of gravity O of the vehicle body 6 when It is represented by
M · Xbdd = K · Xin + K · Xout + T (3)
Ir · θdd = W · (K · Xin−K · Xout + C · Xind−C · Xoutd) / 2 + D · T (4)
However,
T = Cg · Xind · (W + 2D) / 2W + Cg · Xoutd · (W-2D) / 2W (5)
Cg: Damping factor of the lift suppression shock absorber 104 C: Damping coefficient of the roll suppression shock absorber 106 D: Distance between the center of gravity O of the vehicle body 6 and the lift suppression shock absorber 104

The following equation (6) is obtained from the equations (1) and (3).
Cin / Xind + Cout / Xoutd = T (6)
Further, the following expression (7) is obtained from the expressions (2) and (4).
Cin / Xind / Cout / Xoutd = C / Xind-C / Xoutd + 2D / T / W (7)
By adding the left and right sides of the equations (6) and (7), the damping coefficient Cin of the shock absorber 28 for the inner ring during rolling can be obtained by the following equation (8).
Cin = T · (W + 2D) / 2W · Xind + C · (1-Xoutd / Xind) / 2 (8)
Similarly, by subtracting the left and right sides of the equations (6) and (7), the damping coefficient Cout of the shock absorber 28 of the outer ring during rolling can be obtained by the following equation (9).
Cout = T · (W−2D) / 2W · Xoutd + C · (1−Xind / Xoutd) / 2 (9)
Using the equations (8) and (9), the damping forces generated by the shock absorbers 28 on the inner and outer wheels during rolling are obtained by the following equations (10) and (11), respectively.
Fin = Cin · Xind = T · (W + 2D) / 2W + C · (Xind−Xoutd) / 2 (10)
Fout = Cout · Xoutd = T · (W−2D) / 2W + C · (Xoutd−Xind) / 2 (11)

By applying the two-wheel model of the left and right wheels of the vehicle described above to the four wheels 2 of the actual vehicle, the shock absorber 28 corresponding to the inner front wheel, the outer front wheel, the inner rear wheel and the outer rear wheel at the time of rolling can be obtained. The attenuation coefficients Cfin, Cfout, Crin, and Crout are expressed by the following equations (12) to (15), respectively.
Cfin = Tf. (Wf + 2Df) /2Wf.Xfind+Cf. (1-Xfoutd / Xfind) / 2 (12)
Cfout = Tf. (Wf-2Df) /2Wf.Xfoutd+Cf. (1-Xfind / Xfoutd) / 2 (13)
Crin = Tr · (Wr + 2Dr) / 2Wr · Xrind + Cr · (1-Xroutd / Xrind) / 2 (14)
Crout = Tr · (Wr−2Dr) / 2Wr · Xroutd + Cr · (1−Xrind / Xroutd) / 2 (15)
However,
Xfind, Xfoutd, Xrind, Xroutd: Stroke speed of the inner front wheel, outer front wheel, inner rear wheel, and outer rear wheel Df: Distance between the front wheel side vehicle body gravity center and the front wheel side lift suppression shock absorber 104 Dr: rear wheel vehicle body gravity center Distance Wf with front wheel side lifting restraint shock absorber 104: Front wheel tread Wr: Rear wheel tread Cf: Damping coefficient Cr of roll restraining shock absorber 106 disposed on the front wheel side: Rear wheel side Damping coefficient Tf, Tr of roll suppression shock absorber 106: Sum of damping force on front wheel side and rear wheel side Tf = Cgf · Xfind · (Wf + 2Df) / 2Wf + Cgf · Xfoutd · (Wf−2Df) / 2Wf (16) )
Tr = Cgr · Xrind · (Wr + 2Dr) / 2Wr + Cgr · Xroutd · (Wr-2Dr) / 2Wr (17)
Cgf: Damping coefficient of the lift suppression shock absorber 104 disposed on the front wheel side Cgr: Damping coefficient of the lift suppression shock absorber 104 disposed on the rear wheel side

  The roll suppression control described above is performed by executing the control program represented by the flowcharts of FIGS. 5 to 10 together with the pitch control for controlling the pitching due to rolling to an appropriate size. The pitch control is performed by the damping force control of the shock absorber 28 in the transient turning state, and is performed by the braking control in the steady turning state.

  First, an outline of roll control and pitch control will be described with reference to FIG. When the ignition switch is turned on by the driver operating the ignition key, the suspension ECU 10 is activated. First, in S11, the angle of the vehicle body 6 is calculated. That is, the roll angle of the vehicle body 6 and the resulting pitch angle are estimated by calculation. Subsequently, in S12, the rear wheel side target damping force that is the sum of the damping forces of the shock absorbers 28RL and 28RR corresponding to the left and right rear wheels 2RL and 2RR is determined. In S13, the estimated roll angle and the estimated pitch are determined. Based on the angle, a front wheel side target damping force that is the sum of the damping forces of the shock absorbers 28FL and 28FR corresponding to the left and right front wheels 2FL and 2FR is determined. In S14, the target damping coefficients of the shock absorbers 28FL, 28FR, 28RL, and 28RR are determined based on the determined front wheel side target damping force and rear wheel side target damping force, and damping control corresponding to each shock absorber 28 is performed. The actuator 34 is controlled.

Details of S11 to S14 are as shown in FIGS.
First, the estimation of the roll angle will be described based on the roll angle estimation routine of FIG. First, in S21, a sprung acceleration Gzi (i = fl, fr) which is a detection value of the vertical acceleration sensor 38 provided in each of the vehicle body portions 6FL, 6FR, 6RL and 6RR corresponding to the shock absorbers 28FL, 28FR, 28RL and 28RR, respectively. , rl, rr) are read. Subsequently, in S22, the left and right wheel sprung accelerations Gozl and Gozr are calculated by the following equations (18) and (19).
Gozl = (Gzfl·Lr + Gzrl·Lf) / L (18)
Gozr = (Gzfr · Lr + Gzrr · Lf) / L (19)
However,
L: vehicle wheel base Lf, Lr: distance between the center of gravity O of the vehicle body and the front and rear axles

Next, in S23, the roll acceleration Rdd around the center of gravity of the vehicle body is calculated by the following equation (20).
Rdd = (Gozl-Gozr) / W (20)
In S24, the roll angle acceleration Rdd is integrated for the second floor time to calculate the estimated roll angle Re. This estimated roll angle Re assumes a positive value when the vehicle body 6 is rolling in the right direction. Thus, one roll angle estimation is completed.

On the other hand, the pitch angle is estimated by executing the pitch angle estimation routine of FIG.
First, the upper acceleration Gzi (i = fl, fr, rl, rr) is read in S31, and Gzf and Gzr, which are average values of the sprung accelerations on the front and rear wheels, are calculated in S32. Next, in S33, the pitch angular acceleration Pdd is calculated by the following equation (21),
Pdd = (Gzr−Gzf) / L (21)
In S34, the estimated pitch angle Pe is calculated by integrating the pitch angle acceleration Pdd with the second floor time. This estimated pitch angle Pe assumes a positive value when the vehicle body 6 is pitched forward from the neutral posture.

  Next, determination of the sum Tr of the rear wheel side target damping force in S12 of FIG. 5 will be described. This determination calculates the damping force required for the shock absorber 28 on the rear wheel side in order to cancel out the jackup force acting on the rear wheel side of the vehicle body 6 at the time of rolling, and the target damping of the shock absorber 28 on the rear wheel side. This is for setting as a force, and is performed by executing the rear wheel side target damping force determination routine of FIG.

First, in S41, the vehicle speed V, the yaw rate γ, and the lateral acceleration Gy are read from the vehicle speed detecting device 46, the yaw rate sensor 48, and the lateral acceleration sensor 50, respectively. These are substituted into the formula dβ / dt = (Gy / V) −γ to calculate the side slip angular velocity dβ / dt of the vehicle body center of gravity O (S42). By integrating the side slip angular velocity dβ / dt, the side slip angle β at the center of gravity O of the vehicle body is obtained (S43), and is substituted into the equation θr = (γ · Lr / V) −β to obtain the side slip angle θr of the rear wheel. Is calculated (S44). Rear-wheel estimated lateral force Yr is calculated (S45), the rear wheel estimated jack-up force Jr by formula Jr = KJR · Yr ² is calculated based on the the side slip angle θr formula Yr = C · θ / (TrS + 1) (S46). The rear wheel target damping force Tr * is determined to be −Jr so as to just cancel the estimated rear wheel jackup force Jr (S47), which is the rear wheel damping force used in the equations (14) and (15). Is set as the sum Tr (S48).

The determination of the front wheel side target damping force performed in S13 of FIG. 5 is performed by executing the front wheel side target damping force determination routine of FIG.
First, in S51, the target pitch angle Pt is determined using the estimated roll angle Re. This determination is made based on a target pitch angle table representing the relationship between the absolute value of the estimated roll angle Re stored in the ROM of the suspension ECU and the target pitch angle Pt. An example of the target pitch angle table is shown in FIG. In this example, the target pitch angle Pt is increased and the increase gradient is gradually increased as the absolute value of the estimated roll angle Re increases. The target pitch angle Pt always takes a positive value. This means that the vehicle body 6 is inclined slightly forward during rolling. In general, it is said that the turning feeling is better. The target pitch angle Pt can be determined by calculating a function representing the relationship between the estimated roll angle Re and the target pitch angle Pt.

Subsequently, in S52, the corrected pitch angle ΔP is calculated by subtracting the estimated pitch angle Pe from the target pitch angle Pt, and in S53, the corrected pitch angle acceleration Pdd is calculated by differentiating the corrected pitch angle ΔP by the second order time. The Further, in S54, the corrected pitch moment Pm is calculated by the following equation (22).
Pm = Ip / Pdd + Kp / ΔP (22)
However,
Ip: Pitch inertia moment around the vehicle lateral axis passing through the center of gravity O of the vehicle body Kp: Spring coefficient in consideration of pitch rigidity

  In S55, the corrected vertical force ΔTf to be applied to the front wheel side vehicle body is calculated by dividing the corrected pitch moment Pm by the distance Lf between the vehicle body center of gravity O and the front axle, and in S56, the corrected vertical force ΔTf is calculated as described above. The front wheel target damping force Tf * is calculated in addition to Tf (the sum of the currently set front wheel damping forces) used in the equations (12) and (13). In S57, the front wheel target damping force Tf * is calculated. It is set as the current front wheel damping force sum Tf.

  Thus, the determination of the rear wheel target damping force Tr and the front wheel target damping force Tf in S12 and S13 in FIG. 5 is completed. In S14, in order to realize these target damping forces Tr and Tf, the damping force control in FIG. A routine is executed, and damping force control of the shock absorbers 28FL, 28FR, 28RL and 28RR is performed.

  First, in S61, the stroke Xi (i = fl, fr, rl, rr) is read from the vehicle height sensor 36 corresponding to each wheel, and the lateral acceleration Gy is read from the lateral acceleration sensor 50. Then, it is determined whether or not the damping force control of the shock absorber 28 is necessary based on whether or not the absolute value of the lateral acceleration Gy is larger than the threshold lateral acceleration Gy0 (S62). The damping coefficient Ci (i = fl, fr, rl, rr) is set to a value suitable for straight running that is determined in advance. On the other hand, if the determination result is YES, in S64, it is determined whether or not the vehicle is in a transient turning state based on whether or not the absolute value of the differential value ΔGy of the lateral acceleration is greater than the set value ΔGy0 of the lateral acceleration differential value. If the vehicle is in a transient turning state, the determination result is YES, and in S65, Xid (i = fl, fr, rl, rr) is calculated by time differentiation of the stroke Xi (i = fl, fr, rl, rr). . Whether or not the vehicle is turning left is determined based on whether or not the lateral acceleration Gy is positive in S66. If the determination result is YES, S67 to S69 are executed, and if NO, S72 to S74 are executed.

  Assuming that the vehicle is currently turning left, S67 to S69 will be representatively described. In S67, the stroke speeds Xfld and Xrld of the left front wheel 2FL and the left rear wheel 2RL are set as the stroke speeds Xfind and Xrind of the inner front wheel and the inner rear wheel, respectively, and the stroke speeds Xfrd and Xrrd of the right front wheel 2FR and the right rear wheel 2RR are set. Are set as stroke speeds Xfoutd and Xroutd of the outer front wheel and the outer rear wheel, respectively. In S68, these stroke speeds Xfind, Xrind, Xfoutd and Xroutd are substituted into the equations (12) to (15), and the damping coefficient Cj (j = fin, fout, rin, rout) are calculated respectively. In S69, the damping coefficients Cfin and Crin of the inner front wheel and the inner rear wheel are set as the damping coefficients Cfl and Crl of the shock absorber 28 corresponding to the left front wheel 2FL and the left rear wheel 2FR, respectively, and the outer front wheel and the outer rear wheel. Are set as the damping coefficients Cfr and Crr of the shock absorber 28 corresponding to the right front wheel 2FR and the right rear wheel 2RR, respectively. In S70, the damping coefficients of the shock absorber 28 become the set values. Thus, each attenuation control actuator 34 is controlled.

When the steady turning state is reached while the above control is performed and the absolute value of the lateral acceleration differential value ΔGy becomes almost zero, the determination result in S64 is NO, and in S71, the damping coefficient Ci (i = fl, fr , rl, rr) is set to a value determined in advance to a size suitable for turning, for example, a hard-side attenuation number.
Thereafter, in S75, pitch control by braking control is performed.

  It can be considered that the braking control is performed by a control system represented by the functional block diagram of FIG. In this figure, the vehicle is represented by reference numeral 120, and the roll angle Re and pitch angle Pe of the vehicle body 6 thereof are based on the detection values of the four vertical acceleration sensors 38 provided corresponding to the front, rear, left and right wheels 2, respectively. Thus, it is estimated (calculated) by executing the routines shown in FIGS. In FIG. 12, these portions are illustrated as a roll angle detection unit 122 and a pitch angle detection unit 124 for convenience. Then, the target pitch angle Pt corresponding to the estimated roll angle Re is determined in the same manner as S51 of the front wheel target damping force determination routine of FIG. In FIG. 12, this portion is shown as a target pitch angle determination unit 126 for convenience. The corrected pitch angle ΔP is calculated by subtracting the pitch angle (estimated pitch angle Pe) detected by the pitch angle detector 124 from the determined target pitch angle Pt.

The corrected pitch angle ΔP is generated by the corrected deceleration Δα by the braking control. The corrected deceleration Δα is obtained as follows.
The pitch angle P when the deceleration α is generated in the vehicle includes the pitch angle component Ps based on the displacement in the suspension 4 and the pitch angle component Pw based on the displacement generated in the wheel 2 due to the elastic deformation of the tire. Is included.
The pitch angle component Ps and the pitch angle component Pw are expressed by the following equations (23) and (24), respectively.
Ps = (Xf−Xr) / L = K1 · α (23)
Pw = (wf−wr) / L = K2 · α (24)
However,
K1 = (MH / 2L ² ) · {(1-λf) / Kf + (1-λr) / Kr} (25)
K2 = (MH / 2L ² ) · {(1 / kf + 1 / kr} (26)
Kf, Kr: front wheel side and rear wheel side wheel rate kf, kr: front wheel side and rear wheel side tire stiffness λf, λr: front wheel side and rear wheel side anti-dive ratio H: center of gravity height Xf of vehicle body 2 Xr: front wheel side and rear wheel side vehicle height change wf, wr: front wheel side and rear wheel side wheel displacements Note that, as described above, the symbols M and L are the mass of the vehicle body 3 and the wheel base of the vehicle.

Therefore, a relationship of P = Ps + Pw = (K1 + K2) · α is established between the pitch angle P and the deceleration α, and the following is established between the target pitch angle Pt and the target deceleration αt for realizing the relationship. The relationship represented by equation (27) is established.
αt = (K1 + K2) ⁻¹ Pt (27)
Therefore, the relationship of the following formula (28) is established between the corrected deceleration Δαt and the corrected pitch angle ΔPt.
Δαt = (K1 + K2) ⁻¹ · ΔPt (28)

The corrected deceleration Δαt is added to the previous target deceleration αt by the target deceleration determining unit 128 to obtain a new target deceleration αt. The new target deceleration rate α is generated by four hydraulic brakes 68FL, 68FR, 68RL, 68RR provided on the wheels 2FL, 2FR, 2RL and 2RR, respectively.
At that time, a braking force of ½ each may be generated on the front wheel side and the rear wheel side. However, in this embodiment, the braking force Bf on the front wheel side and the braking force Br on the rear wheel side are as follows: It is generated to satisfy the relationship of Eqs. (29) and (30).
Bf = αt ・ M-Br (29)
Br = αt ・ M ・ ρ ・ ・ ・ (30)
However,
ρ: Rear wheel braking force ratio ρ = (Nr · Ar / Af) / (Nf + Nr · Ar / Af) (31)
Af, Ar: Wheel cylinder pressure Nf, Nr on the front wheel side and rear wheel side: Conversion coefficient of wheel cylinder pressure on the front wheel side and rear wheel side to braking force Note that the wheel wheel pressure on the front wheel side of the rear wheel side wheel cylinder pressure Ar The ratio Ar / Af to Af is given by a map or an expression for each value of the target deceleration rate αt so as to realize a so-called ideal braking force distribution in which the front wheels and the rear wheels are simultaneously locked.

As is apparent from the above description, in this embodiment, in the transient turning state, the roll angle and the pitch angle are both controlled to an appropriate magnitude by controlling the damping force in the shock absorber 28. The ride comfort (turning feeling) is improved. Further, after the steady turning state, the roll angle is allowed to increase to a size corresponding to the lateral acceleration or the maximum limit, but the pitch angle is controlled by the deceleration control by the brake system 12 and the roll angle. It continues to be controlled to an appropriate size corresponding to one to one.
Thus, not only the roll angle and the pitch angle are controlled to an appropriate size, but also the pitch angle is controlled according to the change of the roll angle, so the phase of the change of both coincides. In this respect, the effect of improving the riding comfort of the vehicle can be obtained.
Matching the phase difference between the roll angle and the pitch angle in a transient turning state is very effective in improving the turning feeling, but controlling the pitch angle to an appropriate size is possible even in a steady turning state. It is desirable to do. In a state in which the roll angle is kept constant in a steady turning state, the pitch angle is also kept at an appropriate size according to the roll angle.

  In the present embodiment, in the transient turning state, the roll angle is suppressed while suppressing the increase in the center of gravity of the vehicle body, and the pitch angle control is also performed while suppressing the increase in the center of gravity height of the vehicle body. Done. The rear wheel side shock absorber is controlled so as to generate a damping force opposite to the rear wheel side jack-up force, and then the front wheel side shock absorber has its damping force and pitch angle It is controlled to maintain a certain relationship with the roll angle. Thus, if the increase in the height of the center of gravity of the vehicle body is suppressed during turning, the steering stability of the vehicle is improved.

In the present embodiment, the part of the suspension ECU 10 that executes the roll angle estimation routine constitutes a roll angle acquisition unit that acquires the roll angle of the vehicle body. Further, the part of the suspension ECU 10 that executes the pitch angle estimation routine, the front wheel side target damping force determination routine, the rear wheel side target damping force determination routine, and the damping force control routine controls the roll angle according to the roll angle. A corresponding pitch angle control unit is configured, and in particular, by controlling the pitch angle to the size shown in FIG. 11 in relation to the roll angle, the posture of the vehicle body is controlled from the neutral posture to the forward tilt side. A forward tilt control unit is configured.
Of the above-mentioned pitch angle control unit corresponding to the roll angle, the part that executes S75 in particular constitutes a longitudinal acceleration-based pitch angle control unit that controls the pitch angle to a value corresponding to the roll angle. The longitudinal acceleration is controlled by controlling.
Of the suspension ECU 10, a portion of the rear wheel side target damping force determination routine, front wheel side target damping force determination routine, and damping force control routine that executes steps related to the control of the roll angle controls rolling of the vehicle body. A roll control unit is configured, and the pitch angle control unit corresponding to the roll angle controls the pitch angle so as to correspond to the roll angle controlled by the roll control unit.
Moreover, the suspension includes a shock absorber capable of controlling the damping characteristics, and the roll control unit includes a damping characteristic-based roll control unit that controls the roll angle by controlling the damping characteristics of the shock absorber. ing. In addition, a roll angle-corresponding pitch angle control unit controls a damping characteristic-based pitch control unit that controls a pitch angle by controlling a damping characteristic of a shock absorber in a transient turning state of the vehicle, and controls a longitudinal acceleration in a steady turning state of the vehicle. And a longitudinal acceleration-dependent pitch angle control unit for controlling the pitch angle.

In the above embodiment, the pitch angle is controlled by the damping force control of the shock absorber in the transient turning state and the longitudinal acceleration control in the steady turning state. However, the longitudinal acceleration control is also performed in the transient turning state. It is also possible to control the pitch angle. For example, the control of the pitch angle is performed by means represented by the functional block diagram of FIG. 12 while the rolling is suppressed by the same means as the invention described in Patent Document 1.
More specifically, in the above embodiment, after the roll angle estimation routine of FIG. 6 and the pitch angle estimation routine of FIG. 7 are executed, S51 and S52 in the front wheel side target damping force determination routine of FIG. 9 are executed. Then, the corrected pitch angle ΔP is obtained, and the pitch angle control shown in the functional block diagram of FIG. 12 is performed so that the corrected pitch angle ΔP is obtained, and the damping force control of FIG. 10 is executed to suppress rolling. Can be done.

In the above embodiment, the longitudinal acceleration is controlled only by the control of the brake system. However, the longitudinal acceleration is controlled by the drive control together with or instead of the braking control. Is also possible.
An example is shown in FIG. In this embodiment, a drive control unit is added to the embodiment of FIG. That is, a drive electronic control unit (drive ECU) 142 is provided together with the brake ECU 20, and the engine 148 and the transmission 150 are connected to the drive ECU 142 via the engine control actuator 144 and the transmission control actuator 146. The drive ECU 142 controls the driving force of the vehicle by controlling the engine 148 and the transmission 150 via the actuators 144 and 146. If the driving force is reduced, the vehicle can be decelerated, and if the rotational speed of the engine 148 is made lower than that corresponding to the vehicle speed, the engine brake can be applied positively, It can be replaced with control of the system 12. In these cases, it can be considered as a kind of control of longitudinal acceleration by braking, but conversely, if the driving force of the engine 148 is increased, a pitch moment opposite to that during deceleration can be generated, It can be used to control the pitch angle.

  The acceleration / deceleration of the vehicle is controlled by the braking control or driving control by the control of the engine 148 or the transmission 150 and the braking control by the brake ECU 20, and this acceleration / deceleration control includes the driving wheel at the time of acceleration of the vehicle. Since the control conventionally employed in the traction control for suppressing excessive slip can be employed, detailed description thereof is omitted. However, in the traction control, the braking control is performed only on the driving wheel, but in the pitch angle control, the braking control by the brake system is performed not only on the driving wheel but also on the non-driving wheel. Is possible and desirable.

In the above embodiment, the pitch angle is controlled to maintain the non-linear relationship shown in FIG. 11 with respect to the roll angle, but this is not essential, and the pitch angle is linear with respect to the roll angle. It is possible to keep the pitch angle constant, or to keep the pitch angle constant (0 in the illustrated example), as shown in FIG. It is also possible to control the target pitch angle to be different between when the roll angle is increased and when it is decreased.
Furthermore, in controlling the pitch angle, it is effective to cancel the jack-up force on the rear wheel side in order to obtain a grip feeling of steering stability, but at least the pitch angle is equal to the roll angle. It is only necessary to appropriately control the relationship.

In the above-described embodiment, the roll angle and pitch angle are acquired based on the detection result of the vertical acceleration sensor disposed on the vehicle body. Therefore, the roll angle and pitch angle in absolute space are acquired. However, it is also possible to acquire the roll angle and pitch angle based on the detection result of the vehicle height sensor that detects the relative position of the wheel and the vehicle height in the vertical direction. . In this case, the roll angle and pitch angle of the vehicle body with respect to the road surface are obtained.
Further, in the above-described embodiment, the stroke of the shock absorber 28 is detected by the vehicle height sensor 36, and the stroke speed is obtained by differentiation thereof. According to the observer control theory, the detected value of the vertical acceleration sensor 38 is used. Stroke speed can be obtained using an observer.

  Furthermore, the present invention can also be applied to a vehicle having more than four wheels, such as a six-wheeled vehicle. In the above embodiment, the damping coefficient is made hard after the steady turn, but the damping coefficient control may be simply stopped.

It is a figure which shows roughly a part of structure of the vehicle body attitude | position control apparatus which is one Example of this invention. It is a figure which shows roughly another part of the said vehicle body attitude | position control apparatus. It is a figure for demonstrating the principle of the roll control in the said vehicle body attitude | position control apparatus. It is another figure for demonstrating the principle of the roll control in the said vehicle body attitude | position control apparatus. 4 is a flowchart showing a roll / pitch control program executed in the vehicle body attitude control device. It is a flowchart which shows the detail of a part of said roll * pitch control program. It is a flowchart which shows the detail of another one part of the said roll pitch control program. It is a flowchart which shows the detail of another part of the said roll pitch control program. It is a flowchart which shows the detail of another part of the said roll pitch control program. It is a flowchart which shows the detail of another part of the said roll pitch control program. It is a graph showing the relationship between the estimated roll angle used at the time of execution of the said roll pitch control program, and a target pitch angle. It is a functional block diagram which shows another part of the said roll pitch control program. It is a figure which shows schematically a part of structure of the vehicle body attitude | position control apparatus which is another Example of this invention. It is a graph showing the relationship between the estimated roll angle used in the vehicle body attitude | position control apparatus which is another Example of this invention, and a target pitch angle.

Explanation of symbols

  2: Wheels 4: Suspension 6: Vehicle body 10: Suspension electronic control unit (ECU) 12: Brake system 20: Brake electronic control unit (ECU) 26: Wheel holding member 28: Shock absorber 30: Suspension spring 32: Variable throttle mechanism 34 : Damping control actuator 36: vehicle height sensor 38: vertical acceleration sensor 46: vehicle speed detection device 48: yaw rate sensor 50: lateral acceleration sensor 60: hydraulic pressure control actuator 66: power hydraulic pressure source 68: hydraulic brake 70: wheel cylinder 72 : Wheel speed sensor 102: Virtual wheel 104: Lift suppression shock absorber 106: Roll suppression shock absorber 120: Vehicle 122: Roll angle detection unit 124: Pi Chi-angle detection unit 126: the target pitch angle determination unit 128: the target deceleration determination unit 130: target braking force determiner 142: drive electronic control unit (ECU) 144: engine control actuator 146: Transmission control actuator 148: engine 150: Transmission

Claims (7)

(a) a vehicle body; (b) four or more wheels on the front, rear, left and right; (c) a suspension disposed between the four or more wheels and the vehicle body; and (d) the four or more wheels. A device for controlling the attitude of the vehicle body including a braking device that brakes at least some of the wheels, and (e) a driving device that drives at least some of the four or more wheels. And
A roll angle acquisition unit for acquiring a roll angle of the vehicle body;
Look including a roll angle corresponding pitch control unit for controlling the pitch angle of the vehicle body in accordance with the roll angle obtained by the roll angle acquisition unit, and the roll angle corresponding pitch control unit, said braking device By controlling the longitudinal acceleration of the vehicle by controlling at least one of the driving device, the pitch angle of the vehicle body is controlled to a value corresponding to the roll angle acquired by the roll angle acquisition unit. body attitude control apparatus according to claim including Mukoto control unit. The longitudinal acceleration-dependent pitch angle control unit is
A target pitch angle setting unit that sets a target pitch angle based on the roll angle acquired by the roll angle acquisition unit;
An actual pitch angle acquisition unit for acquiring an actual pitch angle of the vehicle body;
The vehicle body attitude control device according to claim 1 , further comprising: a longitudinal acceleration control unit that controls the longitudinal acceleration so that the actual pitch angle acquired by the actual pitch angle acquisition unit approaches the target pitch angle. The longitudinal acceleration control unit is
A brake for applying braking torque to the four or more wheels;
The vehicle body posture control device according to claim 2 , further comprising: a brake control device that controls the longitudinal acceleration by controlling an acting force of the brake. The vehicle body posture control device according to any one of claims 1 to 3 , wherein the longitudinal acceleration-dependent pitch angle control unit includes a forward tilt control unit that controls the posture of the vehicle body to a forward tilt side from a neutral posture. Further comprising a roll control section for controlling the vehicle rolling, the roll angle corresponding pitch control unit, claims 1 to control the pitch angle so as to correspond to the roll angle, which is controlled by the roll control section 4. The vehicle body attitude control device according to any one of 4 above. The suspension includes a shock absorber capable of controlling a damping characteristic, and the roll control unit controls the rolling of the vehicle body by controlling the damping characteristic of the shock absorber. The vehicle body posture control device according to claim 5 , comprising: The suspension includes a shock absorber capable of controlling a damping characteristic, and the pitch angle control unit corresponding to the roll angle controls the pitch of the vehicle body by controlling the damping characteristic of the shock absorber in a transient turning state of the vehicle. The vehicle body attitude control device according to any one of claims 1 to 6 , further comprising a damping characteristic-dependent pitch control unit that controls an angle, wherein the longitudinal acceleration-dependent pitch angle control unit operates in a steady turning state of the vehicle.

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