JP3156502B2 - Suspension preview control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects forward road surface information indicating road surface displacement at a position ahead of a wheel to be controlled, and predicts a vehicle body to be controlled and an actuator interposed between wheels based on the road surface information. The present invention relates to an improvement of a suspension preview control device that is controlled.

[0002]

2. Description of the Related Art As a conventional suspension preview control apparatus for performing preview control, there is one disclosed in, for example, JP-A-4-339010. In this conventional example, the relative displacement between the vehicle body and the road surface is measured at a foreseeing position ahead of the front wheel by a foreseeing control distance, and the vertical acceleration of the vehicle body at this foreseeing position is measured. The vehicle displacement in the vertical direction is obtained by integration, and the absolute displacement of the road surface is obtained by calculating the difference between the vehicle displacement and the relative displacement. Based on the absolute displacement of the road surface and the vehicle speed, the vehicle travels for the foreseeable distance. After that, by controlling the stroke of the active suspension according to the absolute displacement,
This is to perform accurate preview control without measurement errors.

[0003]

However, in the above-described conventional suspension preview control device, only the preview control is individually performed at each wheel position, and the vibration input from each road as a result of the road surface becomes a resultant force and is applied to the vehicle body. There is an unsolved problem that optimal preview control cannot be performed in a vehicle in which a stabilizer is mounted between the left and right wheels without taking into account the action.

That is, in a vehicle equipped with a stabilizer, the stabilizer itself does not act on the bounce component and the pitch component of the vibration input from the road surface, but acts on the roll component of the vibration input from the road surface. Therefore, the vehicle sensitivity to the vibration input in the roll direction increases, and the vibration in the roll direction becomes conspicuous. However, in the conventional suspension preview control device described above, the vibration input from the road surface at each wheel position is reduced by the same degree. However, it is not possible to solve the problem that the vibration in the roll direction is more noticeable than the vibration in the bounce and pitch directions due to the mounting of the stabilizer, and it is not possible to perform optimal preview control.

Accordingly, the present invention has been made in view of the above-mentioned unsolved problems of the prior art, and provides a suspension preview control device capable of performing accurate preview control in a vehicle equipped with a stabilizer. It is an object.

[0006]

According to a first aspect of the present invention, there is provided a suspension preview control apparatus which is disposed between a wheel to be controlled and a vehicle body and controls a control signal. An actuator that generates a control force capable of controlling a stroke between them, and a stabilizer that suppresses relative vertical movement between left and right wheels disposed on at least one of a front wheel and a rear wheel; For predictive control based on road surface information ahead of the wheel to be controlled, a front road surface information detecting means for detecting road surface information ahead of the wheel to be controlled, and a vehicle speed detection for detecting vehicle speed Means, and the control target wheel is grounded from front road surface information of the front road surface information detection means based on a vehicle speed detection value of the vehicle speed detection means. A swing component calculating means for extracting road surface information of the road surface and individually calculating a bounce component, a pitch component and a roll component input to the vehicle body based on the road surface information; and a bounce component and a pitch of the swing component calculating means. Foreseeing control means for calculating a foreseeing control force with a bounce control gain, a pitch control gain and a roll control gain corresponding to these based on the component and the roll component, and outputting a control signal in accordance with the foreseeing force to the actuator, The roll control gain of the preview control means for the actuator on which the stabilizer is mounted is selected to be larger than the other bounce control gain and pitch control gain by the roll rigidity of the stabilizer.

A suspension preview according to claim 2 is provided.
The control device may be configured such that the preview control means includes a suspension for front and rear wheels.
The spring constant of_F,K_RAnd the damping constant is C_F,C_RWhen
And the spring constant of the front and rear stabilizers_{SCIENCE FICTION,}K_SRMade
When the bounce control gain G _B, Pitch control gain G_P
And front and rear wheel roll control gain G_RF,G_RRAnd G_B= K + Cs G_P= K + Cs G_RF= (K + K_{science fiction}) + Cs G_RR= (K + K_SR) + Cs where K = (K_F+ K_R) / 2, C = (C_F+ C_R) /
2 and s are characterized by being selected as differential operators.

Further, in the suspension preview control device according to a third aspect, the front road surface information detecting means has an ultrasonic distance sensor provided in front of a front wheel so as to face a road surface. The output road surface detection value is corrected based on the swinging state of the vehicle body at the position of the ultrasonic distance sensor. Furthermore, in the suspension preview control device according to a fourth aspect, the actuator controls a fluid pressure cylinder interposed between a wheel and a vehicle body and a fluid pressure supplied to the fluid pressure cylinder in accordance with a control signal. And a pressure control valve.

[0009]

In the invention according to the first aspect, the swing component calculating means determines the current control target wheel based on the vehicle speed detection value of the vehicle speed detection means from the road surface information ahead of the control target wheel detected by the front road surface information detection means. Extracts the road surface information of the ground surface where the vehicle is in contact with the ground, calculates the bounce component, pitch component and roll component of the transmission force transmitted from the road surface to the vehicle body based on the extracted road surface information, and performs preview control based on these components. The means calculates a predictive control force based on the control gains corresponding to these components based on the respective components. At this time, since the roll control gain for the wheels equipped with the stabilizer is selected to be larger than the other control gains by the roll rigidity of the stabilizer, the roll vibration transmitted from the road surface to the vehicle body by the stabilizer is effectively reduced. Reduce.

In the invention according to claim 2, the roll control gains of the front and rear wheels on which the stabilizer is mounted are selected to be larger by the spring constants K _SF and K _{SR of} the stabilizer. The transmission force from the road surface to the vehicle body can be reduced more reliably. Further, in the invention according to claim 3, the relative distance between the vehicle body and the road surface detected by the ultrasonic distance sensor is corrected based on the rocking state of the vehicle body, so that an error due to the rocking of the vehicle body is reduced. The removed accurate front road surface information can be obtained.

Further, in the invention according to the fourth aspect, since the actuator is constituted by the fluid pressure cylinder and the pressure control valve for controlling the pressure, the input to the vehicle body based on the control signal from the preview control means. A bounce control force, a pitch control force, and a roll control force for suppressing the bounce component, the pitch component, and the roll component are generated, and accurate preview control is performed.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic configuration diagram showing one embodiment of the present invention, in which 10 is a vehicle body side member, 11FL to 11RR are front left to rear right wheels, and 12 is an active suspension constituting an actuator. Shown respectively.

The active suspension 12 includes hydraulic cylinders 18FL to 18RR interposed between the vehicle body-side member 10 and the respective wheel-side members 14 of the wheels 11FL to 11RR. Pressure control valves 20FL to 20RR for individually adjusting pressures are connected, and these pressure control valves 20FL to 20RR are connected to a hydraulic source 22 for supplying hydraulic oil at a predetermined pressure via a supply pipe 21S and a return pipe 21R. It has a configuration.

The left and right wheels 11FL and 11FR on the front wheel side and the left and right wheels 11RL and 11RR on the rear wheel side are respectively connected at both ends to respective wheel side members 14 and have a central portion rotatably held on the vehicle body side member 10. Stabilizers 16F and 16R are provided. Further, the hydraulic pressure source 22 and the pressure control valve 20FL
Accumulators 24F and 24R for accumulating pressure are interposed in the supply pressure side pipe 21S between .about.20RR.

The active suspension 12 includes, for example, a vehicle speed sensor 26 provided in a speedometer for outputting an analog voltage corresponding to the vehicle speed, and the three wheels 11FR and 11FR.
Vertical acceleration sensors 28FR, 28RL and 28RR for individually detecting vertical acceleration of the vehicle body at positions corresponding to 11RL and 11RR, respectively, and are disposed on the lower surface of the vehicle body in front of the front wheels 11FL and 11FR so as to face the road surface, respectively. Sensor 29L, 2 composed of an ultrasonic distance sensor
And 9R, as well as active control of the pressure control valve 20FL~20RR based on vertical acceleration detection value X _2FR "~X _2RR" of each vertical acceleration sensor 28FR～28RR, each sensor 26,28FR~28FR and 29L, The pressure control valves 20FL to 20FL for the front and rear wheels according to the road surface condition based on the detected value of 29R.
And a controller 30 for individually preview controlling the output pressure of the RR.

Each of the hydraulic cylinders 18FL to 18RR has a cylinder tube 18a.
8a, a lower pressure chamber L separated by a piston 18c having an axial through hole is formed.
A thrust corresponding to the pressure receiving area difference between the upper and lower surfaces and the internal pressure is generated.
The lower end of the cylinder tube 18a is
4 and the upper end of the piston rod 18b is attached to the vehicle body side member 10. Further, each of the pressure chambers L is connected to a pressure control valve 20 FL to 20 FL through a hydraulic pipe 38.
Connected to RR output port.

Each of the pressure chambers L of the hydraulic cylinders 18FL to 18RR is connected through a throttle valve 32 to an accumulator 34 for absorbing unsprung vibration. Hydraulic cylinder 18FL ~
A coil spring 36 having a relatively low spring constant and supporting a static load of the vehicle body is disposed between the upper and lower springs of the 18RR. Each of the pressure control valves 20FL to 20RR has a well-known three-port proportional electromagnetic pressure reducing valve (e.g., a special valve) having a cylindrical valve housing having a spool slidably mounted therein and a proportional solenoid provided integrally therewith. No. 64-74111). Then, the command current i supplied to the exciting coil of the proportional solenoid
By adjusting the (command value), the moving distance of the poppet housed in the valve housing, that is, the position of the spool, is controlled, and the hydraulic source 22 and the hydraulic cylinder are connected via the supply port and the output port or the output port and the return port. 18FL-1
Hydraulic oil flowing to and from the 8RR can be controlled.

FIG. 3 shows the relationship between the command current i (: i _{FL to} i _RR ) applied to the exciting coil and the control pressure P output from the output port of the pressure control valve 20FL (to 20 _RR ). As described above, the minimum control pressure P _NIM is at the minimum current value i _MIN in consideration of noise. When the current value i is increased from this state, the control pressure P linearly increases in proportion to the current value i, when the current value i _MAX is the maximum control pressure P _MAX corresponding to the set line pressure of the hydraulic source 22. This figure 3
Where i _N is a neutral command current and _PCN is a neutral control pressure.

Husband of vertical acceleration sensor 28FR-28RL
As shown in FIG. 4, a vertical acceleration sensor 28FR
Is the vertical acceleration at the left rear position of the front right wheel 11FR of the body.
The sensors 28RL and 28RR are used for the rear wheels 11RL and 11RR of the vehicle body.
It is arranged at a slightly rearward position inside the vehicle. These up and down
The direction acceleration sensors 38FR to 28RR are as shown in FIG.
When the vertical acceleration is zero, zero voltage
When a positive acceleration is detected, a positive
When the analog voltage and downward acceleration are detected,
Vertical acceleration consisting of negative analog voltage according to speed value
Detection value Z_GFR~ Z _GRRIs configured to output
You.

As described above, the vertical acceleration sensor 28FR
As shown in FIG. 4, when the vehicle experiences a bounce acceleration Z ″, a roll angular acceleration φ ″, and a pitch angular acceleration θ ″ as shown in FIG. Vertical acceleration detection values Z _{GFR to} Z _GRR expressed by the following equations (1) to (3) are output from the direction acceleration sensors 28FR to 28RR.

Z _GFR = Z ″ −L ₂ θ ″ + L ₁ φ ″ (1) Z _GRL = Z ″ + L ₄ θ ″ −L ₃ φ ″ (2) Z _GFR = Z ″ + L ₄ θ ″ + L ₃ φ ″ (3) Here, L ₁ is the distance in the left-right direction between the front-rear direction line passing through the center of gravity g of the vehicle and the front right vertical acceleration sensor 28 FR.
₂ longitudinal distance between the left-right direction line and the front right vertical acceleration sensor 28FR passing through the center of gravity point g of the vehicle, L ₃ is the front-rear direction line and the rear left and rear right vertical acceleration passing through the center of gravity point g of the vehicle Left and right distance between sensors 28RL and 28RR, L ₄
Is the distance in the front-rear direction between the left-right line passing through the center of gravity g of the vehicle and the rear left and rear right vertical acceleration sensors 28RL and 28RR.

As shown in FIG. 5, the preview sensors 29L and 29R are connected to the front wheels 11FL and 1FL on the lower surface of the vehicle body.
The front wheel 11FL and the front wheel 11FR are disposed on an extension of the front wheel, facing the road surface on the front side of 1FR. As shown in FIG. 6, these preview sensors 29L and 29R include an ultrasonic wave transmitter 29a that emits ultrasonic waves to the road surface, and a reflected wave reflected by the ultrasonic wave from the ultrasonic wave transmitter 29a on the road surface. , An oscillator 29c for driving the ultrasonic transmitter 29a, and outputs a drive command to the oscillator 29c and receives a signal from the ultrasonic receiver 29b. And a distance measuring circuit 29d for measuring a ground distance by measuring a time from when the ultrasonic wave is transmitted from the ultrasonic wave transmitter 29a to when the reflection is received by the ultrasonic wave receiver 29b. Ground distance detection values _HDL and H which are digital signals representing the ground distance from the measurement circuit 29d.
_DR is output.

As shown in FIG. 7, the controller 30
A / D converters 41FL-41RR for converting the vertical acceleration detection values Z _GFR -Z _GRR input from the vertical acceleration sensors 28FL-28FR into digital values, the vehicle speed detection value V of the vehicle speed sensor 26, the preview sensors 29L, 29R. ground distance detection value H _DL for, H _DR and the a / D converters 41FL~41RR
4 to which the A / D conversion output of is input
2 and a D / A converter 43FL for converting a pressure command value output from the microcomputer 42 into an analog signal.
~43RR and these A / D converters driving an analog signal output from the 43FL~43RR to the pressure control valve 20FL~20RR current i _FL through i into a _FR example driving circuit composed of the floating type constant voltage circuit 44FL-44FR
And

Here, the microcomputer 42 has at least an input interface circuit 42a, an output interface circuit 42b, an arithmetic processing unit 42c and a storage unit 42d. The input interface circuit 42a includes a vehicle speed detection value V, a ground distance detection value X _DL , X _DR and A /
The conversion outputs of the D converters 41FL to 41RR are input, and the pressure control valves 20FL to
The pressure command values P _{FL to} P _RR for 20 _RR are output.

The arithmetic processing unit 42c includes a processing unit shown in FIG.
The processing is executed and a predetermined sampling time T_S(For example, 20
msec), vehicle speed detection value V, ground distance detection value H_DL, H_DR
And body vertical acceleration Z_GFR~ Z_GRRRead, up and down
Direction acceleration detection value Z_GFR~ Z _GRRBased on the following (4)
(6) to calculate the bounce at the center of gravity g
Speed Z ″, pitch angular acceleration θ ″ and roll angular acceleration φ ″
Is calculated, and changes in the posture of the vehicle body are suppressed based on these values.
Generated by each hydraulic cylinder 18FL-18RR
Change suppression control force F_FL~ F_RRIs calculated.

[0026]

(Equation 1)

The arithmetic processing unit 42c has a vertical
Speed detection value Z_GFR~ Z_GRRBased on the following equation (7) and
The formula (8) is calculated and the preview sensors 29L and 29L are calculated.
Vertical acceleration Z at 9R position_PL″ And Z_PR″
And the pair of these and the preview sensors 29L and 29R.
Ground distance detection value H_DLAnd H_DRAnd based on the preview center
Road surface displacement X at positions 29L and 29R_0LAnd X_0RTo
Shifts calculated sequentially and formed in the storage device 42d
The current front wheel is memorized while shifting sequentially to the register area.
And the road surface displacement X of the ground contact road surface of the rear wheel_0FL,X_0FRAnd X
_0RL,X_0RRTransmitted from the road surface to the vehicle body based on the
Transmission force X_b, Pitch transmission force X_pAnd front wheel roll transmission force
X_rF, Rear wheel transmission force X_rRAnd calculate them in advance.
Fixed bounce control gain G_b, Pitch control gain G
_pConsidering the spring constants of the stabilizers 16F and 16R
Front wheel roll control gain G_rF,Rear wheel roll control gain G
_rRIs multiplied by bounce preview control force U_b, Pitch preview control
Force U_pAnd front wheel roll preview control force U_rF,Rear wheel roll preview
Control force U_rRIs calculated, and based on these, each pressure control valve 2
Preview control force U for 0FL-20RR_FL~ U_RRIs calculated,
Posture change suppression control force F _FL~ F_FRAnd preview control force U_FL~ U_RR
Command value P for each pressure control valve based on_FL~ P
_RR, And these are respectively converted into D / A converters 43FL to 43RR.
Output to

[0028] _{Z PL "= Z" -L 6} θ "-L 5 φ" ......... (7) Z PR "= Z" -L 6 θ "+ L 5 φ" ......... (8) In addition, the storage device 42d stores a program necessary for the arithmetic processing of the arithmetic processing device 42c in advance,
A shift register area for storing a predetermined number of road surface displacement amounts X _0L and X _0R while sequentially shifting the calculated road surface displacement amounts X _0L and X _0R is formed for each predetermined sampling time T _S. The results are stored sequentially.

Next, the operation of the above embodiment will be described with reference to the flowchart of FIG. 8 showing the processing procedure of the arithmetic processing unit 42c in the microcomputer 42. That is,
8 is performed for a predetermined sampling time T _S (for example, 10 ms).
ec) is executed as a timer interrupt process. First, in step S1, the vehicle speed detection value V and the vehicle body vertical acceleration detection value Z
_Gi (i = FL, FR, RL, RR) and the ground distance detection value H _Dj (j
= L, R).

Next, the process proceeds to step S2,
Calculate the formulas (4) to (6) and calculate the bounce acceleration.
Z ″, pitch angular acceleration θ ″ and roll angular acceleration φ ″
And then proceeds to step S3 to calculate the calculated
Ounce acceleration Z ″, pitch angle acceleration θ ″ and roll angle acceleration
Based on the speed φ ″, the calculations of the above equations (7) and (8) are performed.
Thus, the vehicle body at the position of the preview sensors 29L and 29R
Vertical acceleration Z_pL″ And Z _pR″ And then
The process moves to step S4.

In step S4, the following equation (9)
As shown in the equation (11), the vertical acceleration Z ″, the pitch angular acceleration θ ″, and the roll angular acceleration φ ″ are represented by first-order lag transfer functions L [fZ], L [fθ] and L [fφ]. The bounce control force FZ, the pitch control moment Mθ, and the roll control moment Mφ are calculated by multiplying the values integrated by the low-pass filter processing by the preset bounce control gain GZ, pitch control gain Gθ, and roll control gain Gφ. .

FZ = GZ · fZ (Z ″) where L [fZ] = 1 / (s + ωZ) (9) Mθ = Gθ · fθ (θ ″) where L [fθ] = 1 / (s + ωθ) (10) Mφ = Gφ · fφ (φ ″) where L [fφ] = 1 / (s + ωφ) (11) Here, fZ, fθ, and fφ are low-pass filters as integrating means. The gains GZ, Gθ, Gφ and the cutoff frequencies ωZ / 2π, ωθ / 2π, ωφ / 2π can be individually set, and s is a differential operator (Laplacian).

Then, the process proceeds to step S5, in which the following equations (12) to (15) are calculated, and the attitude change suppression control force F _FL to generate a translational motion in the four-wheel hydraulic cylinders 18FL to 18RR. ＦF _RR is calculated. _{F FL = (- L r ·} FZ + Mθ + L r · Mφ / d) / 2 (L f + L r) ... (12) F FR = (- L r · FZ + Mθ-L r · Mφ / d) / 2 (L f + L _r )... (13) F _RL = (− L _f · FZ−Mθ + L _f · Mφ / d) / 2 (L _f + L _r )... (14) F _RR = (− L _f · FZ−Mθ−L _f. Mφ / d) / 2 (L _f + L _r ) (15) where L _f is the distance in the front-rear direction from the center of gravity g to the front wheel,
L _r is the front-rear direction distance to the rear wheel from the center-of-gravity point g, d is the lateral direction distance from the center of gravity g to each wheel 11FL～11RR.

Then, the process proceeds to step S6 to perform a second-order low-pass filtering process on the vehicle vertical acceleration detection value Z _pj ″ at the position of the preview sensors 29L and 29R, thereby performing second-order integration to perform vertical integration of the vehicle. Direction displacement H
_{Calculate Uj} . Then, the process proceeds to step S7, and the following formulas (16) and (17) are calculated to obtain the reference distance H _D0 and the vehicle body vertical displacement in the stationary state of the vehicle which are set in advance from the ground distance detection value H _Dj. By subtracting the amount H _Uj , a road surface displacement amount X _0j for estimating the road surface unevenness amount at the preview sensors 29L and 29R is calculated.

X _0L = H _DL −H _D0 −H _UL (16) X _0R = H _DR −H _D0 −H _UR (17) Then, the process proceeds to step S8 to calculate the value. For the road surface displacement amounts X _0L and X _0R , the lower cut-off frequency f _CL
For example 0.5 Hz, performs a band-pass filter processing in which cut-off frequency f _CH of the high frequency side, for example, in 10 Hz, the human sense by reducing the gain of dull low frequency components and high frequency components controlled energy The road surface displacement amounts X _0L and X _0R only in the frequency region necessary for the preview control are extracted by reducing the consumption of the road surface, and the road surface displacement amounts X _0L and X _0R are sequentially stored in the shift register region formed in the storage device 42d.

Next, the process proceeds to step S9, in which the vehicle speed detection value V and the response delay time τ ₁ of the control system set in advance, τ ₁ ,
The preview sensor 29 calculates the following equations (18) and (19) based on a preset controller calculation dead time τ ₂ and a phase delay time τ ₃ by a filter.
The delay times τ _{F and} τ _R until the front wheels 11FL and 11FR and the rear wheels 11RL and 11RR reach the road surface detected by L and 29R are calculated.

[0037] _{τ F = (L P / V} ) - (τ 1 + τ 2 + τ 3) ............ (18) τ R = τ F + (L / V) ............ (19) However, L _P Is a distance between the road surface detected by the preview sensors 29L and 29R and the front wheels 11FL and 11FR, and L is a wheel base. Next, the process proceeds to step S10, where the delay time τ _F stored in the shift register area is set.
And τ _R , respectively, to read the road surface displacement amounts X _DL and X _DR , respectively, and read them out at the present front wheels 11FL, 11FR and rear wheels 11R.
Front wheel side road surface displacement X of the road surface where L and 11RR are in contact with the ground
_0FL , _X0FR and the rear wheel side road surface displacement amounts _X0RL , _X0RR are used to calculate the following formulas (20) to (23) based on these, and the bounce transmission force transmitted to the vehicle body by the road surface displacement amount. X _b, pitch transmission force X _p, the front wheels roll transmission force X _rF
And the rear wheel roll transmission force _XrR is estimated.

[0038] _{X b = X 0FL + X 0FR} + X 0RL + X 0RR ............ (20) X p = X 0FL + X 0FR -X 0RL -X 0RR ............ (21) X rF = X 0FL -X 0FR ... _{......... (22) X rR = X} 0RL -X 0RR ............ (23) Next, the processing proceeds to step S11, the transmission power X _b estimated, X _p, from the road to the X _rF and X _rR bounce control gain G _b represented by the following (24) to (27) below in order to reduce the transmission force to the vehicle body by the input, the pitch control gain G _p, front roll control gain G _rF and rear roll control gain G by multiplying the _rR, below (28) - (31) bounce predictive control force represented by the formula U _b, pitch predictive control force U _p,
Front wheel roll preview control force U _rF and rear wheel roll preview control force U
Calculate _rR .

G_b= K + Cs ... (24) G_p= K + Cs ... (25) G_rF= (K + K_{science fiction}) + Cs ………… (26) G_rR= (K + K_SR) + Cs (27) where K = (K_F+ K_R) / 2, C = (C_F+ C_R) /
2 and K_FIs the spring constant of the front wheel side suspension, K
_RIs the spring constant of the rear wheel suspension, C_FIs the front wheel side
Spence damping constant, C_RIs the rear wheel side suspension
Damping constant, K _{science fiction}Is the spring setting of the front wheel side stabilizer 16F
Number, K_SRIs the spring constant of the rear wheel side stabilizer 16R, s is
Differential operator (Laplacian).

[0040] _{U b = KX b + CX b} '............ (28) U p = KX p + CX p' ............ (29) U rF = (K + K SF) X rF + CX rF '...... (30) _{U rR = (K + K SR} ) X rR + CX rR '...... (31) where, X _b' is a differential value of the bounce transmission force X _b, X _p 'is a differential value of the pitch transmission force X _p, X _rF' front wheel differential value of the roll transmission force X _rF, X _rR 'is a differential value of the front wheel rolls transmission force X _rF.

Here, the front wheel roll control gain G _rF and the rear wheel roll control gain G _rR are changed to another bounce control gain G _b
And the stabilizer 16F of the pitch control gain G _p
The reason for setting to a value larger by the spring constant of 16R and 16R is as described below. The forces R _{FL to} R _RR generated by the suspensions of the respective wheels are determined by the relative motion between the road surface and the suspension mounting portion of the vehicle body, assuming that the control forces generated by the hydraulic cylinders 18 _FL to 18 _RR are U _{FL to} U _RR. Can be represented by

R_FL= K_F(X_0FL-X_1FL) + C_F(X_0FL'-X_1FL') -U_FL…… (32) R_FR= K_F(X_0FR-X_1FR) + C_F(X_0FR'-X_1FR') -U_FR…… (33) R_RL= K_R(X_0RL-X_1RL) + C_R(X_0RL'-X_1RL') -U_RL…… (34) R_RR= K_R(X_0RR-X_1RR) + C_F(X_0RR'-X_1RR') -U_RR…… (35) where X_0FL~ X_0RRIs the vertical displacement of the ground surface of each wheel,
X_0FL'~ X_0RR′ Is its derivative, X_1FL~ X_1RRIs each
Vertical displacement of wheel suspension attachment point on vehicle body, X _1FL′
~ X_1RR'Is its differential value.

The front and rear stabilizers 16F and 1F
Force R _SF and R _SR on roll input generated by 6R
Upon the spring constant of the front and rear stabilizer K _SF, and _{K SR, R SF = K SF} {(X 0FL -X 1FL) - (X 0FR -X 1FR)} ............ (36) R SR = K SR {(X _0RL −X _1RL ) − (X _0RR −X _1RR )} (37)

[0044] Thus, the bounce force R _b generated by the relative motion between the road surface and the vehicle body, a pitch strength R _p and the front wheel roll force R _rF, rear wheel roll force R _{rR is, R b = R FL + R} FR + R RL + R RR _{............ (38) R p = R} FL + R FR -R RL -R RR ............ (39) R rF = R FL -R FR + R SF ............ (40) R rR = R RL - R _RR + R _SR ... (41)

In the above equations (32) to (41), from the road surface
Vibration input is transmitted to the vehicle only on the road surface.
Since the term relates to vertical displacement, the vehicle enters the vehicle from this road surface.
Forced bounce force R_b, Pitch force R_pAnd front wheel roll
Force R_rF, Rear wheel roll force R_rRIs the following formula (42) to (45)
The transmission force R_b, R_pas well as
R _rR, R_rRCan be reduced to zero, stabilizers 16F and 1
Vibration input from the road surface of the vehicle equipped with 6R is transmitted to the vehicle body
Can be reliably prevented.

R_b= K_F(X_0FL+ X_0FR) + K_R(X_0RL+ X_0RR) + C_F(X_0FL'+ X_0FR') + C_R(X_0RL'+ X_0RR') ... (42) R_p= K_F(X_0FL+ X_0FR) -K_R(X_0RL+ X_0RR) + C_F(X_0FL'+ X_0FR') -C_R(X_0RL'+ X_0RR') …… (43) R_rF= K_F(X_0FL-X_0FR) + C_F(X_0FL'-X_0FR') + K_{science fiction}(X_0FL-X_0FR…… (44) R_rR= K_R(X_0RL-X_0RR) + C_R(X_0RL'-X_0RR') + K_SR(X_0RL-X_0RR) (45) For this reason, the road surface estimation estimated in step S10 described above.
Force bounce transmission force X _b, Pitch transmission force X_p, Front wheel low
Transmission force X_rFAnd rear wheel roll transmission force X_rRIs the above (2)
0) to (23), as described above,
Control gain G _b, Pitch control gain G_pAnd front wheel
Control gain G_rF,Rear wheel roll control gain G_rRThe above
By setting equations (24) to (27), the above
Transmission from the road surface expressed by the equations (42) to (45) to the vehicle body
Generates predictive control force that offsets the transmitted force of each component
be able to.

Next, the process proceeds to step S12, where the preview control forces U _b , U _p , and U calculated in step S11 are calculated.
Based on the _rF and U _rR proceeds from the calculated predictive control force U _pFL ~U _pRR performs the following operation (46) - (49) below for each pressure control valve 20FL~20RR to step S13. _{U pFL = U b + U p} + U rF ............ (46) U pFR = U b + U p -U rF ............ (47) U pRL = U b -U p + U rR ............ (48) _{U pRR = U b -U p -U} rR ............ (49) in step S13, the attitude change suppressing control force is calculated each preview control force calculated at step S12 and U _FL ~U _RR in step S5 F _{The following} (50) based on _{FL to} F _RR
The total control forces U _{FL to} U _RR are calculated according to the equations (53) to (53).

[0048] _{U FL = U N -F FL +} U pFL ............ (50) U FR = U N -F FR + U pFR ............ (51) U RL = U N -F RL + U pRL ......... ... (52) in _{U RR = U N -F RR +} U pRR ............ (53) wherein, U _N is the control force necessary to maintain the vehicle height to the target vehicle height.

[0049] Then, the processing proceeds to step S14, the pressure command value corresponding to the control force U _FL ~U _RR calculated in step S13 P _FL to P _RR respectively D / A converter 43FL~4
After outputting to 3RR, the timer interrupt process is terminated and the process returns to the predetermined main program. In the processing of FIG.
The processing of steps S3, S6 and S7 and the preview sensors 29L and 29R and the vertical acceleration sensors 28FR to 28RR correspond to the forward road surface information detecting means.
Step 10 corresponds to the oscillating component calculating means, and step S1
The processing of 1 to S14 corresponds to the preview control means.

Therefore, it is assumed that the vehicle is traveling straight ahead at a constant speed while maintaining the target vehicle height on a flat good road. In this state, since the vehicle maintains the target vehicle height on a flat good road, the vehicle body-side member 10 does not swing, so that the vehicle vertical acceleration detection value Z of each of the vertical acceleration sensors 28FL to 28RR is obtained. _GFR "to Z _GRR" together with becomes substantially zero, preview sensors 29L, ground distance detection value H _DL and H _DR of 29R is substantially coincident with the reference distance H _D0.

Therefore, the vertical acceleration Z ″, the pitch angular acceleration θ ″, and the roll angular acceleration φ ″ calculated in step S2 become zero, and the vertical acceleration Z ″ calculated in step S3 at the position of the preview sensors 29L and 29R. The direction accelerations Z _PL ″ and Z _PR ″ also become zero, and the bounce control force FZ and the pitch control moment M calculated in step S4
θ and the roll control moment Mφ also become zero, and the posture change suppression control force F at each wheel position calculated in step S5
_{FL to} F _RR also become zero.

On the other hand, since the vehicle body does not move up and down and the road surface is flat, the vertical displacement amounts H _UL and H _UR at the positions of the left and right preview sensors 29L and 29R calculated in step S6 are also zero. Also, the road surface displacement amounts X _0L and X _0R at the positions of the preview sensors 29L and 29R calculated in step S7 become substantially zero, and these are subjected to band-pass filter processing in step S8 and formed in the shift register 42d. It is stored while sequentially shifting to the area.

Further, in step S9, the road surface detected by the preview sensors 29L and 29R based on the response delay compensation time τ ₁ of the control system, the controller calculation dead time τ _{2, the} phase delay time τ ₃ by the filter, and the vehicle speed detection value V. The front wheel side delay time τ _F and the rear wheel side delay time τ _R until the front wheels 11FL, 11FR and the rear wheels 11RL, 11RR reach are calculated, and the road surface displacement amount of the shift stage corresponding to these delay times τ _F and τ _R X _0FL, X _0FR and X _0RL, reads the X _0RR, by performing the calculation of the Taken together (20) to (23) below, the bounce transmission when the vibration input from the road surface is transmitted to the vehicle body power X _b, pitch transmission force X _p and the front wheel roll transmission force X _rF, calculates a rear wheel rolls transmission force X _rR. At this time, because the vehicle continues to travel straight on a flat good road,
Since the road surface displacement amounts X _0L and X _0R stored in the shift register area are all substantially zero, the bounce transmission force X _b , the pitch transmission force X _{p, the} front wheel roll transmission force X _{rF, and the} rear wheel roll transmission force X _rR. Are all zero.

[0054] Thus, preview control force U _pFL for each pressure control valve 20FL~20RR calculated in step S12
~U _pRR be all zero, and the total control force U _FL ~U _RR calculated in step S13 becomes a value corresponding only to the neutral pressure control force U _N to maintain a target vehicle height, the pressure command value P corresponding to these _FL ~P _RR is the output side interface circuit 42b
And a driving circuit 44 via D / A converters 43FL to 43RR
Output to FL-44RR.

[0055] Therefore, the driving circuit 44FL~44RR pressure command value P _FL to P _RR to be converted into the command current i _FL through i _RR neutral current i _N corresponding front side of the pressure control valve 20FL~2
0RR. As a result, the pressure control valves 20FL-20
Neutral pressure P _CN required to maintain the target vehicle height from RR is the front wheel side and rear wheel side of the hydraulic cylinder 18FL, 18FR and 18
RL and 18RR, these hydraulic cylinders 18FL-1
8RR generates thrust to maintain the vehicle body at the target height.

In this straight running state on a good road, for example, the left wheel
11FL and the right wheel 11FR
The left wheel 11FL side is higher than the right wheel 11FR side on the road surface.
If there are transient projections, first,
-Sensors 29L and 29R individually detect protrusions
As a result, the ground distance detection value H output from these _DL
And H_DRIs the reference distance H until_D0From
It decreases according to the shape of the projection,
Increases according to the shape of the projection
H_D0Return to.

During this time, the wheels 11FL to 11RR are still flat.
Assuming that you are traveling on a flat road surface, the body will swing
Since there is no preview, the preview calculated in step S3
Vertical acceleration Z at sensor 29L, 29R position_PL″
And Z_PR″ Is calculated in step S6 to maintain the zero state.
The amount of vertical displacement H of the vehicle body issued_ULAnd H_URIs a zero state
Maintain the preview center calculated in step S7.
Road surface displacement X at positions 29L and 29R_0LAnd X_ORBut
It decreases in the negative direction until it reaches the peak of the protrusion,
Becomes the negative maximum value, and then crosses the vertex and goes to zero
It will return to zero when it gets over the protrusion.
You. And these road surface displacement amounts X_0LAnd X _0RIs a bandpa
The shift filter formed in the storage device 42d after the
The data is sequentially shifted and stored in the register area.

The preview sensors 29L, 29
At the time when the road surface protrusion is detected by R, the front wheels 11FL and 1FL
1RL has not yet reached the protrusion, and at this point the shift
Left and right wheel side stored in the
Road surface displacement X_0LAnd X_0RIs substantially zero, so the delay time τ
_FAnd τ_RPrevious road surface displacement X_0FL,X_0FLAnd X_0RL,X
_0RRIs zero, the total control force U on the front and rear wheels is_FL, U_FR
And U_RL, U_RRIs the neutral control force U_NTo maintain.

Thereafter, the front left and right wheels 11FL and 11FR are projected.
When the position is reached, the delay time τ calculated at that time_F
Just before the road surface displacement X stored in the shift register area
_0LAnd X_0RIs the value representing the shape of the projection.
Road displacement X_0LAnd X_0RThe current front left and right wheels 11FL and
Road surface displacement X of the road surface where 11FR touches down_0FLAnd X_0FRWhen
And read, but for the remaining rear left and right wheels 11RL and 11RR
Is the road surface displacement X of those road surfaces that touch_0RLAnd X_0RR
Maintain zero. Therefore, it is calculated in step S10.
Bounce transmission force X_bIs X_b= X_0FL+ X_0FRTona
And the pitch transmission force X_pAlso X_p= X_0FL+ X_0FRWhen
The front wheel roll transmission force X_rFIs X_rF= X _0FL-X_0FRWhen
And rear wheel roll transmission force X_rRIs X_rR= 0.

[0060] Therefore, bouncing preview control force is calculated in step S11 U _b, pitch predictive control force U _p and the front wheel foreseeable roll control force U _rF, rear foreseeable roll control force U _rR is, U _b = K (X _0FL + X _0FR ) + C (X _0FL '+
_{X 0FR ') U p = K} (X 0FL + X 0FR) + C (X 0FL' +
X _0FR ′) U _rF = (K _F + K _SF ) (X _0FL −X _0FR ) + C _F (X
_0FL′− X _0FR ′) U _rR = 0.

[0061] Thus, preview control force U _pFL for each pressure control valve 20FL~20RR calculated in step S12
~U _{pRR is, K F ≒ K R, C} F ≒ C When a _{R, U pFL = K F (} X 0FL + X 0FR) + K R (X 0FL + X
_{0FR) + C F (X 0FL} '+ X 0FR') + C R (X 0FL '
+ X _0FR ') + K _F (X _0FL -X _0FR ) + C
_{F (X 0FL '-X 0FR'} ) + K SF (X 0FL -X 0FR) U pFL = K F (X 0FL + X 0FR) + K R (X 0FL + X
_{0FR) + C F (X 0FL} '+ X 0FR') + C R (X 0FL '
+ X _0FR ') -K _F (X _0FL -X _0FR ) -C
_{F (X 0FL '-X 0FR'} ) -K SF (X 0FL -X 0FR) U pRL = K F (X 0FL + X 0FR) + K R (X 0FL + X
_{0FR) -C F (X 0FL '} + X 0FR') -C R (X 0FL '
_{+ X 0FR ') U pRR =} K F (X 0FL + X 0FR) + K R (X 0FL + X
_{0FR) -C F (X 0FL '} + X 0FR') -C R (X 0FL '
+ X _0FR ').

Each of the _preview control forces _{UpFL to UpRR} is a value corresponding to a force generated in the suspension due to a projection on the road surface through which the front wheels 11FL and 11FR have passed, and the stabilizer 16F is controlled by the front wheel _preview control forces _UpFL and _UpFR. Thus, since the roll vibration component transmitted from the road surface to the vehicle body is considered, it is possible to reliably prevent the vibration input from the road surface from being transmitted to the vehicle body.

That is, the pressure control valve 20 of the front left wheel 11FL
The _preview control force _{UpFL with} respect to FL is ( _X0FL + _X0FR ) <
0, ( _X0FL '+ _X0FR ') <0, ( _{X0FL- X0FR} )
Since <0 and ( _{X0FL'- X0FR} ') <0, the control force is for suppressing the upward bounce caused by the riding on the protrusion, the upward pitch, and the upward movement by the roll rising left. Preview control force U _pFR to the pressure control valve 20FR of the 11FR inhibits upward movement of by the pitch of the bounce and front rising upward by riding projections,
This is a control force for suppressing the downward movement by the downward-sloping roll.

The rear wheel side pressure control valves 20RL and 20RL
Foreseeable control force U for RR_pRLAnd U _pRRAre both on the front wheel side
Bounce upward due to the bump
In addition to suppressing movement, the pitch is lowered downward
It is a control force that suppresses the movement to. Therefore,
In step S13, neutral control force U_NThe posture change suppression control force F_FL~
F _RRAnd the preview control force U_pFL~ U_pRRAdd
By installing the stabilizers 16F and 16R,
Vibration input from the road surface
Prevents transmission to the vehicle body and dramatically improves ride comfort
As well as reliably changing the body posture
Can be suppressed.

Incidentally, the front wheel roll control gain G _rF and the rear wheel roll control gain G _rF are changed to the stabilizers 16F and 16F.
No consideration is given to the spring constant of R, and the bounce control gain G _b
When the control gain is set to be the same as the pitch control gain G _p and the front wheel roll preview control force U _rF and the rear wheel roll preview control force U _rR , the stabilizer 16F for road surface input is used.
And 16R roll force correction terms are no longer included,
Even if the prediction control with sufficiently high estimation accuracy of the road surface is performed,
The transmission force transmitted from the road surface to the vehicle body by the stabilizers 16F and 16R cannot be reduced, and the ride quality deteriorates.

After that, when the front wheels 11FL and 11FR pass through the projection and the rear wheels 11RL and 11RR ride on the projection, the roll suppressing action on the rear wheel side is replaced with the roll suppressing action on the front wheel side. The vibration suppression operation similar to that described above is performed except that the above is exhibited. On the good road, the front wheels 11FL and 11FR and the rear wheels 11RL and 11RR
Varies when the transition to the rough road running state through an uneven, with sequentially detects a ground distance H _DL and H _DR in the pre-Pugh sensor 29L and 29R in the preview sensor 2
The vehicle displacements H _UL and H _UR at the 9L and 29R positions can be accurately calculated, and accurate road surface information ahead of the trajectory through which the wheel to be controlled passes can be obtained. The current front wheel 11
FL, 11FR and rear wheels 11RL, can be calculated predictive control force U _pFL ~U _{pR R} based on the road information of the road surface in contact with the ground of 11RR, that vibration input from the road surface is transmitted to the vehicle body It can be reliably prevented.

Further, when the vehicle is in a turning state and rolls on the vehicle body-side member 10, or when the vehicle is in an acceleration / deceleration state and a pitch is generated on the vehicle body-side member 10, the roll control moment Mφ and the pitch control are determined in step S4. Moment Mθ
Is calculated, and the posture change suppression control forces F _{FL to} F _RR are calculated in step S5 based on these. Therefore, it is possible to suppress the posture change of the vehicle body and secure a good ride comfort.

As described above, according to the above-described embodiment, even in a vehicle equipped with a stabilizer, it is possible to reliably prevent a vibration input from a road surface from being transmitted to a vehicle body, thereby improving riding comfort. And a vehicle vertical acceleration sensor 28FR-28RR for performing skyhook control.
Since the vehicle displacement at the positions of the preview sensors 29L and 29R is estimated based on the acceleration detection value of
There is no need to separately provide a vertical acceleration sensor for detecting the displacement of the vehicle body at the positions of the preview sensors 29L and 29R, so that the cost can be reduced.

In the above embodiment, the case where the ultrasonic distance sensors are applied as the preview sensors 29L and 29R disposed in front of the front wheels has been described. However, the present invention is not limited to this. A sensor may be applied, or a roller or the like that comes into contact with the road surface may be provided to measure the relative displacement between the vehicle body and the road surface, and furthermore, preview sensors may be separately provided on the front wheel side and the rear wheel side. Is also good.

[0070] In the above-described embodiment, a preview sensor 29L and 29R of the ground distance detection value H _DL and H _DR
And the vehicle body displacement amounts H _UL and H _UR , the road surface displacement amounts X _0L and X
_0R is calculated, and the _preview control forces _{UpFL to
Although} the case of calculating _pRR has been described, the present invention is not limited to this, and the preview sensors 29L and 29R
Calculates a differential value of the road surface displacement of ground distance detection value H _DL and H _DR is differentiated by the differentiating circuit, preview sensors 2
Vehicle vertical acceleration Z _PL ″ and Z _PR ″ at 9L and 29R positions
To calculate the vehicle vertical velocity, calculate the difference between the two to obtain road surface information, and set the bounce control gain to G _b = (K
/ S) + C and the pitch control gain is G _p = (K / s) +
C, the front wheel roll control gain is given by G _rF = ｛(K + K _SF ) /
s｝ + C and the rear wheel roll control gain are G _rR = ｛(K + K
_Even if each of them is set to _SR ) / s｝ + C, the same operation and effect as the above embodiment can be obtained.

Further, in the above embodiment, the case where all the operations are performed by the microcomputer 42 has been described. However, the present invention is not limited to this, and it is configured by an electronic control circuit as shown in FIG. You may. That is, the electronic control circuit shown in FIG.
The vertical acceleration sensors 50L and 50R are also provided on the vehicle body side members at the positions L and 29R, and the preview sensors 29L and 2R are provided.
9R and the detected values of the vertical acceleration sensors 50L and 50R are supplied to road surface displacement estimating circuits 51L and 51R, respectively. calculating a vehicle body displacement H _UL and H _UR and floor integration, this body displacement H _UL and H _UR and the reference distance H _D0, ground distance detection value H
Wherein from the _DL and H _DR (16) by performing the calculation of the formula and (17), calculates the road surface displacement X _0L and X _0R.

The road surface displacement estimating circuits 51L and 51R
Road displacement X output from_0LAnd X_0RTo vehicle speed V
Front wheel delay time τ_FAnd rear wheel delay time τ_ROnly
The signals are supplied to delay circuits 52FL to 52RR for
The current front wheels 11FL, 11FR and
Road surface displacement X of the road surface where the rear wheels 11RL and 11RR are in contact with the ground
_0FL,X_0FRAnd X_0RL,X_0RRIs output.

[0073] road displacement X _0FL output from these delay circuits _52FL～52RR, supplies X _0FR and X _{0R L,} the X _0RR the rocking element computing circuit 53 as a swing component calculation unit, the swing component calculation In circuit 53, road displacements X _0FL, X _0FR and X
_0RL, calculated X _0RR by subtracting the bounce component X _b, the pitch component X _p and the front wheel roll component X _rF, the rear wheels roll component X _rR.

The bounce component X _b , the pitch component X _{p, the} front wheel roll component X _{rF, and the} rear wheel roll component X _rR output from the swing component calculation circuit 53 are used for the preview control gain setting circuit 5.
4 are supplied to, earlier in this predictive control gain setting circuit 54 (24) to (27) bounce control gain G _b of the formula, pitch control gain G _p and the front wheel roll control gain G _rR, rear wheel by multiplying the roll control gain G _rR calculated bounce predictive control force U _b, pitch predictive control force U _p and the front wheel foreseeable roll control force U _rF, the rear wheel foreseeable roll control force U _rR.

[0075] bounce predictive control force output from the predictive control gain setting circuit 54 U _b, pitch predictive control force U _p
And a front wheel roll preview control force U _{rF and a} rear wheel roll preview control force U _rR are supplied to a preview control force calculation circuit 55, where the bounce preview control force U _b and the pitch preview control force _{Up are used.} By adding and subtracting the front wheel roll preview control force U _{rF and the} rear wheel roll preview control force U _{rR in accordance} with the equations (46) to (49), the pressure control valves 20FL to 20RR are obtained.
Are calculated for the foreseeing control forces U _{FL to} U _RR .

Further, in the above-described embodiment, the case where three vertical acceleration sensors 28FR to 28RR are disposed and the vertical acceleration is estimated by calculation for the remaining one position has been described. However, the present invention is not limited to this. , 4 wheels 11FL-11
A vertical acceleration sensor may be provided at a position corresponding to RR. Further, in the above-described embodiment, the case where the pressure control valves 20FL to 20RR are applied as the control valve has been described. However, the present invention is not limited to this, and another flow control type servo valve or the like can be applied. .

Further, in the above-described embodiment, the case where the stabilizers 16F and 16R are provided on both the front and rear wheels has been described. However, the present invention is not limited to this, and if one of the stabilizers is omitted, it is omitted. the roll control gain of that side may be set in the same manner as bounce control gain G _b and the pitch control gain G _p. Furthermore,
In the above embodiment, the case where the working oil is used as the working fluid has been described. However, the working fluid is not limited to this, and any working fluid may be used as long as the fluid has a low compression ratio.

[0078]

As described above, according to the first aspect of the present invention, the vehicle speed detecting means detects the vehicle speed of the vehicle speed detecting means from the road surface information ahead of the control target wheel detected by the front road surface information detecting means. Based on the detected value, the road surface information of the road surface on which the control target wheel is currently in contact with the ground is extracted, and the bounce component, pitch component, and roll component of the transmission force transmitted from the road surface to the vehicle body are individually determined based on the extracted road surface information. When the preview control means calculates the preview control force based on the control gains corresponding to these components based on these, the roll control gain for the wheel on which the stabilizer is mounted is changed to another bounce control gain. And the pitch control gain is set to a value larger by the roll rigidity of the stabilizer, so that vibrations input from the road surface and transmitted to the vehicle body are reliably prevented. Being able course, vibration input of a road surface is transmitted to the vehicle body by the stabilizer can also be reliably prevented by performing good preview control, the effect of riding comfort can be improved remarkably obtained.

According to the second aspect of the present invention, the roll control gains of the front wheels and the rear wheels on which the stabilizer is mounted are selected to be larger by the spring constants K _SF and K _{SR of} the stabilizer. Thus, the transmission force from the road surface to the vehicle body can be reduced more reliably. Further, according to the invention according to claim 3,
The front road surface information detecting means is configured to correct the relative distance between the vehicle body and the road surface detected by the ultrasonic distance sensor based on the swinging state of the vehicle body. The effect is obtained that accurate forward road surface information can be obtained by removing the error of the ground distance detection value due to the movement due to the swing.

Further, according to the fourth aspect of the present invention, since the actuator is constituted by the fluid pressure cylinder and the pressure control valve for controlling the pressure, the actuator can be mounted on the vehicle body based on the control signal from the preview control means. Generates bounce control power, pitch control power, and roll control power that suppress the input bounce component, pitch component, and roll component to perform accurate preview control, and in addition to the preview control, the vertical acceleration of the vehicle body And the change in posture of the vehicle body can be reliably suppressed.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram showing a schematic configuration of the present invention.

FIG. 2 is a schematic configuration diagram showing one embodiment of the present invention.

FIG. 3 is a characteristic diagram showing a relationship between a control current and a command current of a pressure control valve.

FIG. 4 is an explanatory diagram showing an arrangement relationship of each sensor.

FIG. 5 is a characteristic diagram illustrating output characteristics of a vertical acceleration sensor.

FIG. 6 is a schematic configuration diagram illustrating an example of a preview sensor.

FIG. 7 is a block diagram illustrating an example of a controller.

FIG. 8 is a flowchart illustrating an example of a processing procedure of a microcomputer.

FIG. 9 is a block diagram showing another example of the controller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Body member 11FL, 11FR Front wheel 11RL, 11RR Rear wheel 14 Body member 18FL-18RR Hydraulic cylinder 20FL-20RR Pressure control valve 22 Hydraulic source 26 Vehicle speed sensor 28FR-28RR Vertical acceleration sensor 29L, 29R Preview sensor 30 Controller 50L, 50R Vertical acceleration sensor 51L, 51R Road surface displacement estimation circuit 52FL to 52FR Delay circuit 53 Oscillation component calculation circuit 54 Control gain setting circuit 55 Preview control force calculation circuit

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60G 17/015

Claims (4)

(57) [Claims] Claims: 1. An apparatus is provided between a wheel to be controlled and a vehicle body,
Having an actuator that generates a control force capable of controlling a stroke between them by a control signal, and having a stabilizer that suppresses relative vertical movement between left and right wheels disposed on at least one of the front wheel and the rear wheel, In a suspension preview control device that performs preview control of the actuator based on road surface information ahead of the control target wheel, a front road surface information detection unit that detects road surface information ahead of the control target wheel, and detects a vehicle speed Vehicle speed detection means, based on the vehicle speed detection value of the vehicle speed detection means, extracts road surface information of the road surface on which the control target wheel is grounded from front road surface information of the front road surface information detection means, based on the road surface information Oscillating component calculating means for individually calculating a bounce component, a pitch component and a roll component input to a vehicle body, and the oscillating component calculation Based on the bounce component, the pitch component and the roll component of the stage, the predictive control force is calculated with the corresponding bounce control gain, pitch control gain and roll control gain, and a control signal corresponding to this is output to the actuator. Control means, and the roll control gain of the preview control means for the actuator on which the stabilizer is mounted is selected to be larger than the other bounce control gain and pitch control gain by the roll rigidity of the stabilizer. Suspension preview control device. 2. The preview control means sets the spring constants of the front and rear wheel suspensions to K _{F and} K _R, and sets the damping constants to C _{F and} C _R.
And then, when the spring constant of the front and rear stabilizer K _SF, and K _SR, bounce control gain G _B, pitch control gain G
_P and the front and rear wheels roll control gain G _RF, the _{G RR, G B = K +} Cs G P = K + Cs G RF = (K + K SF) + Cs G RR = (K + K SR) + Cs _{where, K = (K F + K} R) / 2 , C = ( _CF + _CR ) /
2. The suspension preview control device according to claim 1, wherein 2 and s are selected as differential operators. 3. The front road surface information detecting means includes an ultrasonic distance sensor provided in front of a front wheel so as to face a road surface, and detects a road surface detection value output from the ultrasonic distance sensor as the ultrasonic distance. The suspension preview control device according to claim 1 or 2, wherein the correction is performed based on a swing state of the vehicle body at the sensor position. 4. The actuator comprises a hydraulic cylinder interposed between a wheel and a vehicle body, and a pressure control valve for controlling a hydraulic pressure supplied to the hydraulic cylinder in accordance with a control signal. The suspension preview control device according to any one of claims 1 to 3, wherein: