JPS60113712A - Control of steering characteristic for car - Google Patents

Abstract

PURPOSE:To secure the steering stability and traveling stability having high quality by installing a traveling-state judging means for judging the traveling state on the basis of the signals of steering angle and steering angle speed and a control means for controlling a driving mechanism on the basis of the result of judgement. CONSTITUTION:A steering-angle detector 27 outputs the detection signal theta corresponding to the steering angle of a steering wheel, and a steering-angle speed calculation circuit 29 performs sampling of the signals theta and compares the signals theta and compares the signal value with the preceding sampling value and outputs the voltage output theta' corresponding to the steering angle speed. A traveling-state judging apparatus 30 is constituted of a straight-advance state detecting circuit 31, steering-state detecting circuit 32, straight-advance judging circuit 33, sharp steering judging circuit 34, and a fixed steering judging circuit 35, and judges traveling state. The control signal CS which is supplied into a controller 52 on the basis of the output signal of the traveling-state judging circuit 30 and operates the driving circuit for torsional-rigidity varying stabilizers 10A and 10B on the basis of these signals is output.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for controlling steering characteristics of a vehicle in which the steering characteristics are changed depending on the driving condition of the vehicle.

[Prior art]

A conventional vehicle steering characteristic control method ζ is disclosed in, for example, Japanese Utility Model Application Publication No. 55-109008. In summary, in a vehicle equipped with a shock absorber, this method controls the damping characteristics of at least one force of each shock absorber on the front and rear wheels depending on the vehicle speed.
At high vehicle speeds, the damping force of the shock absorber on the rear wheel side is lowered relative to the 611 wheel side to create an understeer characteristic, while at low vehicle speeds, the damping force relationship is reversed to that described above, resulting in a neutral Stair to overstair 1. This is a suspension for a vehicle that controls steering stability by controlling the steering stability.

Another conventional example is disclosed in Japanese Utility Model Application Publication No. 56-103307. This device is configured to detect the steering angular velocity of the vehicle instead of detecting the vehicle speed in the conventional example, and change the steering characteristics of the vehicle based on the detected signal.

However, in such a conventional vehicle steering characteristic control method, the steering characteristic is simply detected and controlled by vehicle speed or steering angular velocity. It is not possible to perform fine-grained steering characteristic control such as steering characteristic control, steering characteristic control according to the steering speed during steering, and steering characteristic control when holding the steering wheel, and it is not possible to perform a It was still not enough to ensure stability and running stability.

[Purpose of the invention]

This invention was made by focusing on the five points of improvement in the control method at the end of IjL, and detects the steering angle and steering angular velocity of the vehicle and determines whether these are within predetermined values. However, it is an object of the present invention to improve the conventional example by determining the driving condition of the vehicle and performing fine-tuned steering characteristic control corresponding to the driving condition of the vehicle.

[Structure of the invention]

In order to achieve the above object, the present invention provides a vehicle in which steering characteristics can be changed by a drive mechanism.
a steering angle detector that detects a steering angle; a steering angular velocity calculation circuit that calculates a steering angular velocity based on a steering angle detection signal from the steering angle detector and outputs a steering angular velocity signal; A driving state determining means for determining whether the vehicle is traveling straight, turned, or left unturned based on the detection signal and the steering angular velocity signal of the steering angular velocity calculation circuit, and one of the driving state determining means.
The present invention is characterized in that it has a control means for controlling the drive mechanism described in item 111 based on the results of the determination, and has a characteristic that changes depending on the running condition.

[Effect]

The present invention provides a driving state determining means for a vehicle in which steering characteristics of the vehicle can be changed by a drive mechanism.
The driving state of the vehicle, such as going straight, turning, and holding the steering wheel, is determined, and based on the results of the judgment, the control means applies strong/understeer characteristics when the vehicle is traveling relatively straight, and changes to weak understeer characteristics when the vehicle is turning sharply. When the steering wheel is held, the steering characteristics are controlled to neutral 1 to normal, respectively, and the optimum steering characteristics corresponding to the driving condition of the vehicle are determined.

〔Example〕

The present invention will be explained below based on the drawings.

1 to 6 are diagrams showing one embodiment of the rice bowl invention.

48 in FIG. 1, IOA and IOB are the torsional rigidity variable stabilizer C, the suspension arm I2L, which supports the front wheels 11L, IIR, and the rear wheels 13L, 13R. The Suspension 7'-
] 4L and 14R, respectively.

Gorera torsional rigidity j-iJ variable stabilizer, l0I
An example of 3 is 1-1 Shonhar 1 as shown in Figure 2.
5 is the center portion 15C and its left and right end portions 151-.

1.5 I? The left and right end portions 15L and 15R are rotatably pivoted in line with the center portion 15C. The left and right end portions 15L and 15R each have a cylindrical base portion 16,
It is composed of a plate part 17 with a rectangular cross section connected to this,
The tip of the plate part 17 is the suspension arm 12L, 12
R, 14L, and 1417, respectively, so as to be rotatable. A rotating arm 18 is integrally attached to the rear end of the base 16, and the rotating arms 18 at both left and right ends 15L and 15R are connected by a connecting rod 19. and,
The rotating arm 18 on the left end 15■7 is the solenoid 2.
0 actuator 21 is connected. In this case, although not shown, the abdomen of the solenoid 1-20 is inserted into the actuator 21, and the IM return spring normally operates the actuator 21.
1 is held in a contracted state.

Therefore, in this state, both the left and right end portions 15L.

The plate portion 17 of 15R is in a state where its width direction is the horizontal direction, and therefore its 14-1 plane coefficient becomes small, and the torsional rigidity of the variable scrubberizer IOA and 1013 is reduced. . Also, if the solenoid 20 is energized from this state and the actuator 21 is extended completely,
The plate portion 17 is rotated 90 degrees so that its width direction becomes the vertical direction, so that its section modulus increases, resulting in the torsional rigidity variable stabilizer 10A.

The torsional rigidity as 10B is increased. Then, the solenoid 20 is driven and controlled by a drive circuit 22.

Further, 23 is a vehicle speed detector, which detects the rotation speed of a propulsion shaft 26 that transmits the rotational output of the transmission 24 to the final reduction gear 25 using rotation detection means such as magnetic or optical. A voltage detection signal vp corresponding to the rotation speed of the shaft 26 is output.

27 is a steering angle detector, and the steering wheel 2
The rotation angle of the steering wheel 280 is detected by a potentiometer or the like, and a detection signal θ corresponding to the steering angle of the steering wheel 280 is detected.
is output. In this case, the detection signal θ is, for example, a predetermined voltage V when the steering wheel 28 is in the neutral position.
When the steering wheel 28 is turned to the right from this state, a voltage V h higher than the voltage VO is applied depending on the rotation angle, and when the steering wheel 28 is turned to the left, a voltage ve lower than the voltage Vo is applied depending on the rotation angle. It is configured so that it occurs.

29 is a steering angular velocity calculation circuit which is supplied with the detection signal θ of the steering angle detector 27, and differentiates this detection signal θ or samples the detection signal θ at predetermined time intervals and uses the sampling value as the value. The difference is calculated by subtracting the previous sampling value, and a voltage output υ corresponding to the steering angular velocity is output.

Reference numeral 30 denotes a driving state determination device, which includes a straight-ahead state detection circuit 31 that determines whether the vehicle is traveling straight, and a driving state detection circuit 31 that determines whether the vehicle is in a turning state in which the steering wheel 28 is rotated. a steering state detection circuit 32 that outputs a detection signal representing a straight-ahead running state based on an output signal of the straight-ahead state detection circuit 31; and an output signal of the straight-ahead state detection circuit 31 and the steered state detection circuit 32. A sudden steering determination circuit 34 outputs a detection signal indicating a sudden steering running state based on the output signal, and similarly outputs a detection signal representing a steering holding running state based on the output signals of the straight running state detection circuit 31 and the steering state detection circuit 32. and a constant circuit 35 for maintaining the steering.

The straight-ahead state detection circuit 31 is supplied with, for example, the detection signal θ of the steering angle detector 27 and is connected to the steering wheel 28.
If the detection signal of the steering angle detector 27 when the steering wheel is in the neutral position is 00, then the value obtained by adding the play of the steering wheel 28 ±θc to this θ0 is (θ0+θ^), (θ0−θ8
) are supplied as reference voltages θU and θL, and the steering angle detection signal θ is θL≦0.
When ≦θ(1, a logical value “i” is output, and in other cases, a logical value “o” is output.)

The steering state detection circuit 32 also includes the steering angular velocity calculation circuit 2.
The comparator 37 is supplied with an output signal θ of 9 and a predetermined set steering angular velocity signal θS, and has a logic value of “1” when the output signal θ is θ≧θS, and a logic value when θ<θS. A judgment output SI3 represented by the value "P0" is output.

Furthermore, the straight run '111 constant rotation 11δ33 is a monostable circuit whose one input side is directly fed with the output signal SΔ of the straight run state detection circuit 31, and whose other input side is triggered at the rising edge of the output signal SΔ. An l-gate 39 to which the output signal of 38 is supplied, and the output signal thereof is supplied to the cent terminal, the sharp turning 1' constant signal ST of the sudden steering judgment circuit 34 and the steering holding judgment output signal of the steering holding judgment circuit 35. S H is or game I/4
0 and a flip-flop circuit 41 respectively supplied to the reset terminal via the flip-flop circuit 4.
A straight-line determination signal SS having a logical value of "1" from "1" is output.

The sudden steering determination circuit 34 has one input side supplied with the output signal SΔ of the straight-ahead state detection circuit 31 via the impark 42, and the other input side supplied with the output signal SΔ of the steering state detection circuit 32.
Ant gate 43 to which B is supplied, and a monostable circuit 44 to which the output signal of Ant gate 1-43 is directly supplied to one input side and which is triggered at the rising edge of the output signal of Ant gate 43 to the other input side. Antoge 1-45 is supplied with the output of , and its output is supplied to the seven-arrow αj1□i child, and the straight-ahead determination output signal SS of the straight-ahead determination circuit 33 and the rudder-holding determination output signal 311 of the rudder-holding determination circuit 35 The flip-flop circuit 47 is supplied to the reset terminal 1 through the 1-46, and the flip-flop circuit 47 outputs a pre-sudden turn determination signal ST having a logical value of "1".

When the steering assistance state display output time +i'& 35 is input, the output signal SΔ of the straight running state detection circuit ■Raku 3I is supplied to one input terminal, and the output signal SB of the steering judgment circuit 32 is input to the input side of the other power. The output signal of the ant gate 49 is directly supplied to one input terminal, and the output signal of the ant gate 49 is directly supplied to the other input terminal. Ant gate 51 is supplied with the output signal of monostable circuit 50 which is 1-triggered at the rising point.

Here, the monostable rotation [/838.4.4 and 50] are the steering conditions in the steady state and in the steered state, whose time constants are "temporary steering hold" that occurs when turning back during steering. Temporary straight movement 1 that occurs when the wheel 28 passes through the neutral position
'1j is selected at a time when no steady state is detected, and at that time the output signal maintains the logic value "1" and changes from the logic value "1" to the logic value "O" when triggered. It is configured to output an output signal.

Reference numeral 52 denotes a control device to which the driving state 111, the straight-line judgment signal %SS of the constant device 30, the sharp turning judgment signal S1 and the O3 steering holding judgment signal SH, and the detection signal P of the vehicle speed detector 23 are supplied. Based on each signal, a control signal C5 is outputted to operate the drive circuit 22 of the torsionally variable stabilizer IOA, IOB. An example of this ii control device 52 includes a strong understeer 7 control circuit 53 to which a vehicle speed detection signal VP and a straight-ahead determination signal SS are supplied, and a weak understeer control circuit 53 to which a vehicle speed detection signal VP and a 1'+1 constant signal ST before sudden turn is supplied. f
'J+1 circuit 54, jI speed detector vp and rudder maintenance 'l
1 and a neural steering control circuit 55 to which a constant output signal 311 is supplied.

The strong understeer control circuit 53 controls the torsional rigidity variable stabilizer 10B of the rear wheel side in response to the vehicle speed detection signal ■P during the period when the straight-ahead judgment signal -SS is the logical value "'1". The torsional rigidity of the variable torsional rigidity stabilizer 10A is increased to improve the front wheel side 1:
The drive circuit 22 is controlled to increase the value.

Therefore, the excitation current value output from the drive circuit 22 is controlled to a predetermined value, and this excites the solenoids 20 of the torsional rigidity variable stabilizers IOA and 10B, causing their actuators 21 to expand and contract by a predetermined amount, thereby increasing the torsional rigidity. change. As you can see, the torsional rigidity variable stabilizer IO on the front wheel side
FIG. 4 shows the results of an acceleration turning test using a vehicle with an increased roll lql ratio of vehicle A. In FIG. 4Q, a characteristic curve 56 shown by a solid line is the test result when the roll stiffness loss ratio is changed.
Characteristic curve 57 L; l, shown by the dashed line, according to the invention)
・This is the test result of a vehicle with increased role sharing ratio of 10Δ widening property change squirting riser. As is clear from this Figure 4, 'R+l! l: Curve 57-1 Understeering compared to characteristic curve 5G.

Similarly, a frequency response test was conducted on both vehicle sides, and the results are shown in FIG. As can be clearly seen from FIG. 5, the vehicle of the present invention has a peak frequency of 2l-I''<it'-I'', which is shallower than the 11η vehicle of the secondary vehicle.
In addition, the phase characteristics have been improved, so 1 mulberry 0ε response 1!
It can be understood that l, force < good.

The weak understeer control circuit 54 controls the vehicle speed (moxibustion 1
]” (In response to the word VP - [the above strong understay? 1li
ll tall ll:I l'7 row 53 control signal C
Compared to 5, it is overall lower than Hell's 111J tall Shin-C'F and twists the formation variable Stahirai blade! 108, 10
It outputs to the drive circuit 22 of B and stabilizes the front wheel side stabilizer 10.
∆'s 1'' - Le Tsuyoshi 1! 1-5] The carrying rate is the production force / υ Koi stage i
The torsional property of the front wheel side stabilizer blade '0Δ is reduced to the extent that it rotates countersunk than the angle 111.11.

-゛New I Ralsteer System j] 11 circuits 55, (
Kazuki Kimi't11 Sadanobu: B S 11 or logical value "1"
During a certain period, i1 Horen) Total 1) According to the word υ VP, when driving generously, the II bulge of the push 1-ζ running 1 Tililt trace was 44. 1 return loli of front eave a +IIN+ so as not to
11(,+J-hen Stahirai+J-'10△'s 1st return 14th grade Mr. I-1: Sa-l-ru ili'l ?1llll
(The word -CI-+ is output to the drive U++ circuit 22 and the I call is 11 minutes.) The 111 rate is lowered and the vehicle is driven 2J--1.

Next, the effect will be explained. Is the vehicle driving straight? Gorge Teshi 1 surrender! Since the steering wheel 28 is in the substantially neutral position, the detection signal θ[, J
, as shown in FIG. 6, aL≦θ≦θU, and therefore, the straight-ahead state detection circuit 31 of the running state determination device 30 outputs a logical straight line “1” (@, %3Δ. ζ, straight ahead?111 The constant circuit 33 outputs the straight ahead determination signal SS from the time delayed by the time constant τ seconds of the monostable circuit 38. In response, the strong unsteer control circuit !l+853 of the control device 52 outputs the straight ahead determination signal SS. The control signal CS corresponding to the i1j continuous detection signal vp at the time is outputted to each torsion +711+ (1i1J variable stabilizer 10Δ, 10B driving times +1.; 22, 1 return rigidity variable stabilizer 4J' on the front wheel side
IO8 later)・An example of a torsional rigidity variable stabilizer! I
O + 1 returns 1 and returns 1 r7] 11 life is increased, and its roll (IX
It daytime stability is Rfll I”A:.

J2) From this state, at the point L2 when we return to Figure 6,
Turn the ring wheel 28 to the right and turn 1 before the sudden turn.
1. Steering; 1; Voltage Vh higher than neutral voltage Vo from steering angle detector 27 in response to rotation of eel 28
A detection signal θ is output, and this detection signal θ is θ〉θ
Therefore, the straight-ahead state detecting circuit 31 detects a logic value of "0". On the other hand, the output signal θ of the steering angular velocity calculation circuit 29 to which the detector 0 of the steering angle detector 27 is supplied increases, and this output signal 6 becomes θ>S. An output signal of logical value "P1" is output from the output signal.

Accordingly, when the flip-flop circuit 47 of the pre-sudden turn judgment circuit 34 is delayed by the time constant τ seconds of 111 stable times 1?84"4, it is 7 I-, and becomes the 1% I logical value "l". The sudden steering determination signal sequence S'F is output.Therefore, the control signal υCT is output from the weak understeer control circuit 54 of the control device 52.
(Jj is supplied to the drive circuit 22 of the torsional rigidity variable stabilizer lOA, 10B, and their torsional rigidity is W1 constant value L.
J is lowered, and the ratio of stiffness shared by the front wheels (11 to 1) to the variable stiffness stabilizer l remains relatively high, and the vehicle is slightly unsteered.

As a result, the steering response when steering on a steep bank becomes high (at the same time, the roll of the vehicle is moderately suppressed, the one-edge stability is increased to 1:11, and it is possible to perform stable sharp turns.

From this state, when the steering state is stopped at time t3 and the steering state is shifted to the holding state, the detection A1-1 θ of the steering angle detector 27 is kept at a relatively high value, so that the steering state is straight ahead! The detection circuit 3
The output signal SA of 1 has the logical value "0" for j'ff.However, since the steering wheel 28 no longer rotates, the detection t=signal of the two steering angular velocity calculation circuits indicates that θ≦ θS, and the output signal S T3 of the turning state 1 detection circuit 32 becomes the logic value “o”. Therefore, the logic value “1” is reached at the time when the time constant τ seconds of the small stability circuit 50 is delayed from the steering holding judgment circuit 35. "f^rudder '1" 11 constant ℃SII is output. For this reason, sudden steering 'l''I 5'4 output times jlF
The solinobu flop circuit 43 of the controller 52 is reset, and the neural control circuit 55 of the control device 52 outputs the 'r'i shift to the detection 1+ of the vehicle speed detector 23 at that time.
The control signal CS caused by p is outputted to the drive circuit 22 of the return stiffness variable stabilizer 10Δ, 1(+13), and 1j;
1-wheel side torsion type i variable stabilizer IOA and 1 multi-wheel side (111 V;
I return trill of B (make J equal to 111j) ζ,
Convert the vehicle to neutral steering. As a result, it is possible to prevent the travel trajectory from bulging and ensure stable circular turning travel.

In addition, when a turn is made while making a sharp turn, such as in S-curve driving, the detection signal θ of the steering angular velocity calculation circuit 29 becomes θ<l)s at the time of the turn, and the output of the turning state roughness circuit 32 The signal υS 13 temporarily becomes the logical value 0". At this time, the steering holding judgment circuit 35 selects the AND gate 4.
The output of the monostable circuit 50 has a logic value of "1", but at this point the output of the monostable circuit 50 has a logic value of "0", so the unl-case is
1-51 maintains the logical value "o", and the rudder holding judgment circuit S1-1 maintains the logical value "o". Therefore, the solinob flop circuit 47 of the pre-sudden turn determination circuit 34 is not reset, so that the D steering determination signal S T (, J
, maintains the logical value "1". the result,! I (both are
It is possible to maintain weak understeer, and maintain one-edge stability and running stability during sharp turns.

Furthermore, when the steering wheel 28 exceeds the neutral position and is about to make a sudden turn, the detection signal °C of the steering angle detector 27 temporarily changes to θ in the vicinity of the neutral position of the steering wheel 28, and becomes θ≦θ≦θU. The output signal SA of the straight-ahead state detection circuit 31 temporarily becomes the logic j11'f ``l''.

At this time, the input signal of the straight-ahead judgment circuit 33 becomes a logic value "1", but at this point the output of the i11 stable 10) path 38 is a logic value "0", so the output of the an1-gate 39 maintains the logical value “0”, and the flip-flop circuit 41
has the reset state H2C, and the straight-ahead judgment signal SS also has the logical value "o"V4I-'i! + Therefore, the flip-flop circuit 47 of the sudden turning judgment circuit 34 is not turned off, so the sudden turning f1 judgment signal ST maintains the logical value "1".

As a result, the vehicle can maintain weak understeer characteristics and maintain ΣIiX stability and running stability during sharp turns.

In addition, in the above long journey example, ζ was explained for the case where the torsional rigidity variable stabilizer 10A and IOB were installed on both the front wheel side and the rear wheel side of the vehicle. When a torsionally variable stabilizer is provided and a torsionally variable stabilizer is provided on the front wheel side, the torsional rigidity is increased, and when a torsively rigidity variable stabilizer is provided on the rear wheel side, the torsional rigidity is lowered. It is possible to increase the share of roll stiffness on the front wheel side.

Further, the torsional rigidity variable stabilizer IOA, 10B is not limited to the above configuration, but may have a configuration in which the torsional rigidity can be changed by the operation of the drive device. It goes without saying that a variable stabilizer can be applied, and in addition, the drive device is not limited to the solenoid l"20, but any drive device such as a linear actuation device such as a fluid pressure cylinder, a rotational drive device such as a motor, etc. can be applied. I can do it.

Furthermore, in order to make the vehicle understeer using the variable stabilizer, it is not only necessary to increase the roll stiffness sharing ratio of the torsional rigidity variable stabilizer 10Δ on the front wheel side, but also to make the roll steer characteristics become roll under. In general vehicles with a suspension device set to
Roll underli is achieved by reducing the rigidity of the front wheels and wheels regardless of the ratio of the rigidity of the front and rear wheels.
It is also possible to strengthen the t-characteristics.

Further, in order to cause the vehicle to understeer, it is not limited to controlling the torsion [critility variable squeezer], but it is also possible to control the damping force variable shock absorber 60 shown in FIGS. 7 and 8. Zunawara, front wheel 1. LL, II
Variable damping force shock absorbers 6o are attached to the R and rear wheels 13L, ], 3R, respectively. This variable damping force shock absorber 60';I:, as shown in FIG.
A screw inside the cylinder 61!・It has a configuration in which a vist 763 is slidably disposed at the tip of the shaft 1-62.

And the piston 63 has '5:! J is open to the center distance +165 which communicates with the performance chamber A via the liquid passage 64 bored in the piston rono 1-62, and the T liquid chamber B which communicates with this.
A liquid passage 1'L67 is provided in the central opening 65, and a spool 68 is slidably disposed within the central opening 65 and has a through hole 1'L67 that communicates the interior thereof with the liquid passage 66. The spool 68 is normally held downward by the return spring 69.
The lower position is controlled by the plunger 70, and in this state, the through hole 67 takes a position where it does not face the opening θ1;1 of the liquid passage 66, and therefore, the center distance 1 65 and the liquid passage 66 are in a non-communicating state. Furthermore, each time the plunger 70 is energized and energized by the electromagnetic solenoid 1-71 disposed around it, it is moved in three directions in proportion to the amount of energized current, thereby causing the spool 6B to move upward. center opening 65
The flow area between the liquid passage 66 and the liquid passage 66 is changed, and the damping force is also changed.

Thus, each variable damping force shock absorber 60 is controlled by the above-mentioned control device 52 to control its strong understeer control circuit 5.
3, the damping force of the variable damping force shock absorber 60 on the front wheel side is made higher than that of the variable damping force shock absorber 60 on the rear wheel; controls the damping force of the front wheel variable damping force shock absorber 60 to a predetermined value or lower, and further weakens the damping force of the front wheel side variable damping force variable shock absorber 60 by the neural steer control circuit 55. Control as follows.

In addition, in a vehicle having the suspension device which is set so that the 11-steer characteristic becomes roll steer, the steering characteristic due to the above-mentioned stabilizer; l1ll? ff
Similar to l+, the total damping force on the front and rear wheels is reduced regardless of the damping force sharing ratio of each of the front l and wheels, and 1-1-
It goes without saying that there are many things that can be done to strengthen Luanda's characteristics.

In addition, in order to make the vehicle understeer, as shown in FIG. 9, a steering mechanism 77 consisting of a servo valve 75 and an actuator 76 is installed on the rear wheels 13L and 13R.
The steering mechanism 77 may be slightly steered by the control device 52 in the same phase as the steering mechanism t++X on the front wheel side.

Further, the driving state determination bag RFI 30 and the control device 52 are not limited to the above configuration, and the microphone IJ:
:+7 A heater may be used for control.

[A) Results of the invention]

IEI-1 - As described, according to the present invention, in a vehicle whose steering characteristics can be changed by a drive groove, there is provided a steering angle detector for detecting a steering angle; a steering angular velocity calculation circuit that calculates a steering angular velocity based on a lateral angle detection signal and outputs a steering angular velocity signal; and a steering angular velocity calculation circuit that calculates a steering angular velocity signal based on a lateral angle detection signal; a driving state determining means for determining whether the vehicle is traveling straight, turning, or holding the steering wheel; and a control means for controlling the drive mechanism based on the determination result of the traveling state determining means, and the steering system is configured to control steering characteristics according to the driving state. As a result, it is possible to perform optimal roll steer control according to driving conditions such as driving straight ahead, driving before a sudden turn, and driving while holding the steering wheel, thereby improving handling stability and driving stability. The effect is IM.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of the present invention, and FIG.
1 is a perspective view showing an example of a stabilizer with variable return stiffness, FIG. 3 is a block diagram showing an example of a control device, and FIG. Graph showing the relationship between turning and side angle change, 5th
FIG. 6 is a graph showing the relationship between yaw rate gain and phase in line with frequency, FIG. 6 is a signal waveform diagram for explaining the present invention in detail, and FIG. 7 is a schematic diagram showing other embodiments of the present invention. Figure 8 is a sectional view showing an example of a variable damping force shock absorber, and Figure 9 is a schematic configuration diagram showing still another embodiment of the present invention. 10A, 1Of3... Torsional rigidity variable stabilizer, ]11. ．． ．． 11R...Front wheel, 13L, 1
3R・old・rear wheel, 15・・・・1・-John version,
2o...Solenoid, 22...Drive old 1st road, 23...Vehicle speed detector, 27...
Steering angle detector, 29...Steering angular velocity calculation circuit,
30・・・・・・Driving status ゛1′ determining device, 31・Old・
・Straight running state detection circuit 'd8.32...Steering state detection circuit, 33...Straight running '1' foot circuit, 34.
. . . Pre-sudden turn judgment circuit, 35 . . . Rudder holding judgment circuit, 52 . . . Control device, 53 . . . Strong understay 7 control circuit, 54 . . . ... Weak antasteno ° control time 1? δ, 55...Neutral steer control times 1? 8.60...Damping force ii J variable absorber, 77...L & wheel steering mechanism

Claims (2)

[Claims] (1) The steering characteristics can be changed by the drive mechanism.
A steering angle detector that detects a steering angle; a steering angular velocity calculation circuit that calculates a steering angular velocity based on a steering angle detection signal from the steering angle detector and outputs a steering angular velocity signal; The vehicle moves straight based on the angle detector's detection signal and the steering angular velocity calculation circuit's corpse steering angular velocity.
a running state determining means for determining the running state of steering and holding;
a control means for controlling the drive mechanism based on the determination result of the driving state determining means, and the steering characteristic control method for a vehicle is characterized in that the steering characteristic is adjusted according to the driving state. (2) The control means determines whether the vehicle is running straight or not.
The vehicle according to claim (1), wherein the steering characteristics are relatively i;47 understeer, weak understeer, and neutral 1-ral steer in each state of steering and steering holding. steering characteristic control method.