JPH0514652B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to a vehicle body attitude control device that controls the tilting attitude of a vehicle body in the left and right direction. and is useful for improving maneuverability.

"Prior Art and Problems" As shown in Figure 11, when a car turns, a centrifugal force μW acts on the car body T, causing the car body T to lean toward the outside of the curve. In other words, rolling occurs. Here, μ is the lateral acceleration, W is the weight of the vehicle body, and the centrifugal force is the product of both μW.

FIG. 13 schematically shows this rolling. The vehicle body T is tilted by the roll angle φ in the direction in which the centrifugal force μW acts, the outer suspension spring 51 is compressed, and the inner suspension spring 51 is compressed.
Spring 52 is stretched. Note that when the centrifugal force μW is not acting, as shown in FIG. 12, the suspension springs 51 and 52 have the same length, and the roll angle φ of the vehicle body T is 0°.

When the vehicle body T rolls, the center of gravity of the vehicle body T moves outward and a moment due to centrifugal force acts, so that the load applied to the wheels is biased outward. This impairs driving stability and, in extreme cases, can cause drift, spin, or rollover.

Therefore, in order to obtain running stability when turning, it is necessary to suppress rolling as much as possible.

By the way, devices for keeping the vehicle height constant regardless of changes in the operating condition or load of the vehicle are disclosed in Japanese Patent Publication No. 59-14365 and Publication Utility Model Publication No. 59-11767, for example.

However, these conventional devices do not have a sufficient effect of suppressing rolling, so there is a problem with stability when turning.

Also, JP-A-59-114104 and JP-A-59-206261
The control device disclosed in the publication describes detecting the lateral acceleration when the vehicle is turning and controlling the vehicle height, but when adjusting the vehicle height, it simply controls the left and right side of the vehicle. Simply making adjustments to equalize the load distribution does not improve driving safety, and furthermore, it is not possible to avoid deterioration in maneuverability or the possibility of rollover.

``Object of the Invention'' An object of the present invention is to provide a vehicle body attitude control device that can actively suppress rolling caused by lateral acceleration to which the vehicle body is subjected, thereby improving the running stability of the vehicle. .

``Structure of the Invention'' The vehicle body posture control device of the present invention includes a vehicle height adjusting means for adjusting the vehicle height on the left and right sides of the vehicle body, and a minimum height adjusting means for adjusting the vehicle height on the left and right sides of the vehicle body, and a minimum height adjustment device for detecting that the vehicle height on the left and right sides of the vehicle body has reached the lowest controllable position. high detection means, vehicle speed detection means for detecting vehicle speed, acceleration detection means for detecting lateral acceleration received by the vehicle body, when the vehicle speed obtained by the vehicle speed detection means is equal to or higher than a predetermined value, the acceleration obtained by the acceleration detection means is Based on this, a target roll angle is calculated to roll the vehicle body in the opposite direction to the roll direction caused by centrifugal force in order to approximately equalize the load sharing between the left and right wheels, and when the vehicle speed is less than a predetermined value, the vehicle body is maintained in a horizontal position. The desired roll angle is achieved by setting the desired roll angle to 0 by setting the desired roll angle calculation means and by setting the vehicle height on the side facing the lateral acceleration to the lowest height detected by the minimum vehicle height detecting means. The vehicle height adjustment means is configured to include a control means for controlling the vehicle height adjustment means.

"Example" The present invention will be explained in more detail below based on the example shown in the drawings. Here, FIG. 1 is a block diagram showing a vehicle body attitude control system according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of the installation of a vehicle height adjustment means and a roll angle sensor on the right rear wheel of an automobile, and FIG. 4 is a diagram illustrating the configuration of the roll angle sensor; FIGS. 5 a to 5 e are a flowchart of the operation of the vehicle attitude control device shown in FIG. 1; and FIG. FIG. 7 is a schematic diagram for explaining the movement of the vehicle body T of a vehicle having the vehicle body attitude control device shown in FIG. 7, and shows a state in which there is no centrifugal force. 6 and 8 illustrate the movement of the vehicle body T in a state where it is not activated.
The figure shows the target roll angle θ ₀ when centrifugal force is applied.
Figure 9 is a diagram equivalent to Figure 6 in a state where = 0 is achieved, Figure 9 is a diagram equivalent to Figure 6 when attitude control is achieved to roll in the opposite direction when centrifugal force is applied, and Figure 10 is a diagram equivalent to Figure 6.
The figure is a schematic external view of the automobile in the state shown in FIG. 9. Note that this invention is not limited to this.

As shown in FIG. 1, the vehicle body attitude control device 1 includes:
Vehicle height adjustment means 2a, 2b, 2c, 2d, vehicle speed sensor 3, steering sensor 4, microcomputer system 5, and base height switch 6
a, 6b, and roll angle sensors 7a, 7b.

The vehicle height adjusting means 2a, 2b, 2c, and 2d are provided corresponding to the right rear wheel A, the left rear wheel B, the right front wheel C, and the left front wheel D, respectively. To explain a specific configuration example of the vehicle height adjustment means 2a corresponding to the right rear wheel A, as shown in FIGS. 2 and 3, it is provided between the vehicle body T and the axle housing Xa and is connected to the hydraulic cylinder 11a and the suspension Shion
This is a vehicle suspension system in which a spring 12a is connected in series. The hydraulic cylinder 11a adjusts the vehicle height, and the suspension spring 12a functions to absorb vibrations. The specific configurations of the other vehicle height adjusting means 2b, 2c, and 2d are also similar.

Another specific example of the structure is
Examples of such systems include a hydroneumatic system in which the vehicle height is adjusted using hydraulic pressure as disclosed in Japanese Utility Model Publication No. 11767/1983, an air spring system, and a system using both an air spring and a coil spring.

As the vehicle speed sensor 3 (vehicle speed detection means), for example, a conventional sensor for a speedometer can be used.

The steering sensor 4 is, for example, a slit plate attached to the steering shaft, and the amount of rotation of the slit plate is detected by a photo interrupter.

These vehicle speed sensor 3 and steering sensor 4
cooperate to function as acceleration detection means. That is, the vehicle speed sensor 3 determines the speed v, the steering sensor 4 determines the turning radius r, and the lateral acceleration μ is calculated from these. The formula for this calculation is μ=(v·v)/r.

Note that in place of the vehicle speed sensor 3 and steering sensor 4, conventionally known acceleration detection means using a piezo element or the like may be used.

The microcomputer system 5 has wheels A,
In order to eliminate the imbalance in load sharing among B, C, and D,
It calculates the angle at which the vehicle body T is rolled in the opposite direction to the roll direction caused by the centrifugal force μW, that is, the target roll angle θ ₀ , and the vehicle height adjustment means 2 a, 2 b, 2 c, etc. are adjusted to achieve the target roll angle θ ₀ . 2d. This will be explained in detail later.

The base height switches 6a, 6b are for detecting the base positions of the vehicle height adjusting means 2a, 2b.
As shown in the figure, a limit switch can be used that is turned on when the hydraulic cylinder 11a is fully retracted and turned off at other times (when it is extended).

The roll angle sensor 7a, as shown in FIG.
The rotating part of the potentiometer 15a attached to the bottom of the vehicle body T, which is a sprung member, is connected to the link 16.
A configuration is adopted in which the axle housing Xa is connected to the axle housing Xa, which is an unsprung member, via the axle housing Xa and the axle housing Xa, which is an unsprung member.

Although the axle housing Xa is at a substantially constant position relative to the road surface, the vehicle body T is displaced due to rolling or the like. Therefore, the car body T and rear axle housing
The potentiometer 15a provided between Xa changes its output signal in accordance with the displacement of the vehicle body T, thereby making it possible to detect the roll angle θ of the vehicle body T.
The roll angle sensor 7b also has a similar configuration.

In addition, as another example of the structure, for example,
A roll angle sensor composed of a magnet and a magnetoelectric conversion element as disclosed in Japanese Patent No. 14366 can be used.

FIG. 4 shows the roll angle detection circuit, in which the output signals Va and Vb from the left and right roll angle sensors 7a and 7b are filtered through low-pass filters 21a and 21.
While outputting as V ₁ and V ₂ respectively via b,
This circuit inputs these signals to the differential amplifier circuit 22 and generates an output signal V ₀ according to the output difference (Va-Vb) between the two. The larger the roll angle θ of the vehicle body T, the greater the difference between the outputs of both potentiometers 7a and 7b (V ₁ −V ₂ ).
becomes large, so based on this the output signal V ₀
Therefore, the roll angle θ can be determined.

Also, since the height of the vehicle body T decreases as the vehicle weight W increases, each potentiometer 7a, 7b
The output values V ₁ and V ₂ of increase or decrease. Therefore, the vehicle weight W can be determined based on these output values V ₁ and V ₂ . That is, the roll angle sensor 7
a and 7b can function as vehicle weight detection means.

Note that the low-pass filters 21a and 21b remove unnecessary high-frequency components generated by vibrations of the vehicle body T and the like.

Next, the operation of the vehicle body attitude control device 1 of the present invention will be explained with reference to FIGS. 5 to 10. These operations are performed with the microcomputer system 5 at the center. In the following explanation, S0 to S28 indicate each process number in the flowchart shown in FIG.

As shown in FIG. 5a, when the key switch of the automobile is turned on, the microcomputer system 5 starts and initializes the system (S0).

Next, read the left and right base height switches 6a and 6b (S1), and if these are not on, the vehicle body T
lower the height to the base height. For this purpose, we first perform left base conversion (S3), but this process
As shown in Figure b, the left base height switch 6b is read (S30), it is determined whether it is on or off (S31),
If it is off, pressure oil is removed from the left hydraulic cylinder 11b in order to lower the vehicle height on the left side (S33).
Next, right base conversion (S4) is performed, but this process is
As shown in FIG. 5c, the right base height switch 6a
is read (S40), it is determined whether it is on or off (S41), and if it is off, pressure oil is removed from the right hydraulic cylinder 11a in order to lower the vehicle height on the right side (S43).

After confirming that the left and right base height switches 6a, 6b are turned on and the vehicle body T has been lowered to the base height on both sides (S2), the microcomputer system 5 calculates each value V ₁ of the roll angle sensors 7a, 7b,
Load V ₂ , then for a predetermined period of time (e.g. 1 second)
Then, read it again and calculate the average value Vm of all (S5).

Since the car is still stationary, its body T
The height is determined by the balance between the vehicle weight W and the suspension springs 12a, 12b, 12c, and 12d. Since the characteristics of the suspension springs 12a, 12b, 12c, and 12d are constant depending on the vehicle, the output values V ₁ and V ₂ of the roll angle sensors 7a and 7b read at this time vary depending on the vehicle weight W. This is a uniquely determined value. The average value memorized in advance
Vehicle weight W is determined from the relationship between Vm and weight W (S6). The purpose of taking the average value Vm is to suppress errors and improve measurement accuracy.

By actually measuring the vehicle weight W in this way,
The centrifugal force μW applied to the vehicle body T can be calculated accurately, and therefore the attitude of the vehicle body T can be accurately controlled.

Next, the microcomputer system 5 calculates a target roll angle θ ₀ that determines the attitude of the vehicle body T.
Two methods are used to determine this target roll angle θ ₀ . If the vehicle speed v is less than 60 km/h, set θ ₀ = 0° so that the vehicle body T is always kept in a horizontal position, and set the vehicle speed v
If is 60 Km/h or more, determine the target roll angle θ ₀ in the opposite direction to the centrifugal force μW and at a size corresponding to the magnitude of the centrifugal force μW so as to cancel out the bias in load sharing due to the influence of the centrifugal force μW. do.

That is, as shown in FIG. 5d, the vehicle speed v is read by the vehicle speed sensor 3 (S7), and the vehicle speed v is 60 km/h.
If it is less than 0, set the target roll angle θ ₀ to 0 (S8,
S9).

On the other hand, if the vehicle speed v is 60 km/h or more, the steering angle is read as the output of the steering sensor 4,
The corresponding turning radius r is determined, and μ is calculated from the turning radius r and the vehicle speed v by μ=(v·v)/r. Then, after a short period of time (for example, 0.2 seconds),
Repeat the same process again and calculate μ in the same way as above. Then, the average of these two values of μ is taken as the lateral acceleration μ. The reason why the average of two times is taken in this way is that attitude control is not performed for instantaneous steering operations, but only when continuous steering operations are determined to be a true turn and attitude control is performed.

Next, the vehicle weight W and lateral acceleration μ found above
Calculate the centrifugal force μW based on Then, the target roll angle θ ₀ corresponding to the centrifugal force μW is determined based on a comparison table set in advance. In addition,
As described above, the direction of the target roll angle θ ₀ is opposite to the direction of the lateral acceleration μ (S11).

The comparison table for calculating the target roll angle θ ₀ from the centrifugal force μW is a one-dimensional array, but instead of this, the target roll angle θ ₀ can be calculated from the vehicle weight W and the lateral acceleration μ.
It is also possible to use a two-dimensional array-like table to find the . Alternatively, the calculation may be performed using an experimentally obtained calculation formula.

Once the target roll angle θ ₀ is determined in step S9 or S11, the actual roll angle θr and its actual roll direction are read from the output V ₀ from the roll angle sensors 7a and 7b (S12).

Next, it is determined whether the target roll angle θ ₀ is 0 (S13).

If θ ₀ =0, then it is determined whether the actual roll angle θr is 0 (S14).

If the actual roll angle θr = 0, the target roll angle θ ₀ =0 has already been achieved and the vehicle body T is maintained in a horizontal position, so the vehicle body height can be increased without controlling the roll angle θ. control. That is, the height of the vehicle body T is lowered to the base height by the same processes S1' to S4' as explained in steps S1 to S4.

When both the left and right sides of the vehicle body T reach the base height, the hydraulic cylinders 11a to 11d are held in that state, that is, the height of the vehicle body T is maintained, and the process returns to step S7 (S15).

By the way, in step S14, if the actual roll angle θr is not 0, it is determined whether the actual roll direction is to the right (S16), and if the actual roll direction is to the right, the right side of the vehicle body T is too low or the is too high, so in order to achieve the target roll angle θ ₀ =0, it is necessary to raise the right side of the vehicle body T or lower the left side of the vehicle body T. Therefore, in order to decide which method to select, the left base height switch 6b is read (S17).

If the left base height switch 6b is on, the vehicle body T
The left side of is at base height. Therefore, since the left side of the vehicle body T cannot be further lowered, the right side must be raised. On the other hand, if the left side is not at the base height, the left side of the vehicle body T can be further lowered. Step S18 is a process for making this selection.

If the left side of the vehicle body T is at the base height, pressure oil is sent to the hydraulic cylinders 11a and 11c on the right side of the vehicle body T to raise the vehicle height on the right side (S19).

On the other hand, if the left side of the vehicle body T is not at the base height, pressure oil is removed from the left hydraulic cylinders 11b and 11d of the vehicle body T, and the vehicle height on the left side is lowered (S20). At the same time, in order to make the entire car body T the lowest height, the right base is created (S4″).This right base is created (S4″)
is the same process as the right base conversion (S4) described above.

If it is determined in step S16 that the actual roll direction is not to the right, this means that the actual roll direction is to the left. Therefore, step S17~
The same processing as described in S20 is performed with the left and right sides reversed (S21 to S24 and S3'').

After these processes, the step S7
It returns to .

The above explanation will help you understand the attitude control of the vehicle body T when the target roll angle θ ₀ =0, but to summarize here, when the vehicle speed v is less than 60 km/h,
The attitude of the vehicle body T is always controlled so that it does not roll. Moreover, the height is always the lowest that can be controlled. The state of the vehicle body T at this time will be further explained later with reference to FIG.

Next, a case where the target roll angle θ ₀ is not 0 will be explained.

In step S13, the target roll angle θ ₀ is 0.
If not, then it is determined whether the target roll angle θ ₀ and the actual roll angle θr are equal (S25).

If θr=θ ₀ , it is determined whether the direction of the target roll angle and the actual roll direction match (S26).

If the direction of the target roll angle and the actual roll direction match, the target roll angle has already been achieved, so the vehicle height can be adjusted to the lowest height without controlling the roll angle θ. Control. That is, as shown in FIG. 5e, the left and right base height switches are read (S1''), and it is determined whether either the left or right is at the base height (S27).This step S27
Detecting either the left or right base height means determining whether the hydraulic cylinder on the side facing the lateral acceleration μ (for example, inside the curve) is at the base height. are doing.

This is because in a natural state, the suspension spring on the side facing the same direction as the lateral acceleration μ (for example, on the outside of a curve) contracts more than the suspension spring on the side opposite to the lateral acceleration μ; Since the angle θ ₀ is the roll angle in the opposite direction to the roll angle φ due to the centrifugal force μW, in order to achieve the target roll angle θ ₀ , the hydraulic cylinder on the side facing the lateral acceleration μ must be the one on the opposite side. This is because the height of either the left or right vehicle body T is the base height, the expansion and contraction of the hydraulic cylinders 11a to 11d is stopped to maintain the left and right vehicle height, and the vehicle height is reduced. (S15).

On the other hand, when neither the left nor the right is at the base height, the left and right hydraulic cylinders 11a to 1 are used to further lower the vehicle height while maintaining the desired roll angle θ ₀ .
1d is reduced at the same time (S28).

After the above step S15 or S28, the process returns to the above step S7.

In step S26, if the direction of the desired roll angle and the actual roll direction do not match, it means that the actual roll direction of the vehicle body T is opposite to the direction of the desired roll angle. Therefore, first, it is determined whether the direction of the target roll angle is to the right (S29), and if it is right, the current state of the vehicle body T is opposite to the purpose, because the right side of the vehicle body T is too high and the left side is too low. Therefore, the height of the left side of the vehicle body T is raised (S23') and the base is changed to the right side (S24'').

On the other hand, if the intended roll direction is not right, it is the left, so the right side of the vehicle body T is raised (S19') and the vehicle body T is made to be based on the left (S3''), contrary to the above.

After the step S3'' or S4'', the process returns to the step S7.

Now, if the target roll angle θ ₀ and the actual roll angle θr are not equal in step S25, it is determined whether the actual roll angle θr is larger than the target roll angle θ ₀ (S30).

If the actual roll angle θr is larger than the target roll angle θ ₀ , then it is determined whether the actual roll direction and the direction of the target roll angle are equal (S26').

If the direction of the target roll angle and the actual roll direction match, it means that the roll angle is over controlled, so it is necessary to return it a little.

Therefore, it is determined whether the actual roll direction is to the right (S16'), and if the actual roll direction is to the right, the left side is too high, so the left side of the vehicle body T is lowered (S20')
At the same time, the right side is made into a base (S4″).

On the other hand, since the actual roll direction is not right, it is left, so the right side of the vehicle body T is too high. Therefore, the right side of the vehicle body T is lowered (S24') and the left base is changed (S3'').

After these steps, the process returns to step S7.

Now, if the intended roll direction and the actual roll direction are different in step S26', then the roll direction is opposite to the intended roll direction, so steps S29, S23', S19', S3'', and S4'' are The same thing as explained in the series of processing is performed and the process returns to step 17.

Further, if the actual roll angle θr is not larger than the target roll angle θ ₀ in step S30, steps S29, S23′, and S4″ are performed to add the missing amount to achieve the target roll angle θ ₀ . ,S19′,
The process of S3'' is performed and the process returns to step S7.

The above is the attitude control when the target roll angle θ ₀ is not 0.

Next, how the vehicle body T moves as a result of the attitude control described above will be explained with reference to FIGS. 6 to 10.

First, FIG. 6 is a schematic diagram of an automobile equipped with the vehicle body T attitude control device 1 of the present invention, and shows a state in which lateral acceleration μ is not applied (μ=0). When the vehicle speed is less than 60 km/h, the target roll angle θ ₀ = 0, and even if the vehicle speed is 60 km/h, the centrifugal force μW
=0, so the target roll angle θ ₀ =0 as well. Therefore, in this case, the right hydraulic cylinder 11
a, 11c and the left hydraulic cylinders 11b, 11d are both at the base height, and the length A ₀ of the right suspension spring 12a, 12c and the length B ₀ of the left suspension spring 12b, 12d. are becoming equal.

Suspension spring 12a at this time
As described above, the length of ~12d is determined by the weight W of the vehicle body T, and by detecting this with the roll angle sensors 7a and 7b, the vehicle weight W can be measured.

Next, FIG. 7 shows a state in which the vehicle body T rolls when subjected to centrifugal force μW when the vehicle body attitude control device 1 of the present invention is not functioning. That is, left and right suspension springs 1
A roll angle at which the roll stiffness basically determined by 2a to 12d, the centrifugal force μW determined by the lateral acceleration μ and the weight W of the vehicle body T, and the movement of the center of gravity due to rolling of the vehicle body T are balanced. φ
The vehicle body T is rolling in the direction of centrifugal force.

The length A ₁ of the outer suspension spring in the direction in which the centrifugal force μW acts is compressed by the increased load due to the centrifugal force μW and the movement of the center of gravity of the vehicle body T, and is reduced to A ₀ >A ₁ . On the other hand, the length B ₁ of the inner suspension spring in the direction in which the centrifugal force μW acts is opposite to the above, and expands as the load is reduced.
B ₀ <B ₁ holds true.

This state directly represents the rolling state in conventional automobiles, and as understood from the imbalance between the lengths A ₁ and B ₁ of the outer and inner suspension springs in the direction in which the centrifugal force μW acts, There is also an imbalance in the load distribution between the outer and inner vehicle wheels, which has a negative impact on driving stability.

However, in the present invention, when the vehicle speed is less than 60 km/h, attitude control is performed to achieve the target roll angle θ ₀ =0. Therefore, as shown in FIG. 8, the outer vehicle body T on which the centrifugal force μW acts is lifted by a hydraulic cylinder, and the vehicle body T is controlled in a horizontal position. At the same time, the inner vehicle height in the direction in which the centrifugal force μW is applied is adjusted to the lowest controllable height by retracting the hydraulic cylinder to the base position. At this time, the center of gravity of the vehicle T will no longer shift, so
The left and right suspension springs have a centrifugal force μW
There is a difference in length sufficient to support the Therefore, if we compare it with the state shown in Fig. 7, A ₁ <A ₂ ,
B ₁ >B ₂ , and the imbalance in load sharing between the left and right wheels is reduced to some extent.

Also, the inner car body T in the direction in which the centrifugal force μW acts
Since the height of the vehicle is reduced to the lowest possible height, the running stability of the vehicle is improved.

An even bigger effect is the effect it has on the driver, since the vehicle body T maintains a horizontal position, there is no need to take an unreasonable posture, and it becomes possible to drive with psychological stability. be.

In this way, the attitude control with the target roll angle θ ₀ =0 when the vehicle speed v is less than 60 km/h is as follows:
This is because at vehicle speeds of less than 60 km/h, the unbalance of left and right loads due to centrifugal force μW is not usually a problem, and the above-mentioned effect on the driver was given more importance.

On the other hand, if the vehicle speed v is 60km/h or more,
Since load imbalance caused by centrifugal force μW becomes a problem, the target roll angle θ ₀ is set to be opposite to the natural roll angle φ.

Fig. 9 shows a state in which attitude control is being performed to achieve this target roll angle θ ₀ , in which the outer vehicle height in the direction in which the centrifugal force μW acts is raised, and the inner vehicle height is the lowest controllable height. It is said that

At this time, in order to move the center of gravity of the vehicle body T in the direction opposite to the lateral acceleration μ, the centrifugal force μW
A component in the opposite direction is generated, and the imbalance in the load distribution between the left and right sides is reduced accordingly.

Ideally, the centrifugal force μW would be completely canceled out, and the load would be shared equally between the left and right sides. That is, in an ideal situation, the lengths A ₃ and B ₃ of the left and right suspension springs would be equal. however,
Since it supports the centrifugal force μW, the
It will be shorter than A ₀ and B ₀ .

FIG. 10 depicts the appearance of the automobile in a state where the attitude control shown in FIG. 9 is performed. 1st
If compared with Figure 1, the difference from the conventional one will be clearly understood.

Now, as can be understood by referring to FIG. 6, FIG. 8, and FIG. 9, the vehicle body attitude control device 1 of the present invention
In this case, the attitude of the vehicle body T is controlled and the vehicle height is controlled to be lowered to the lowest possible height in that attitude. This prevents the center of gravity from becoming too high and improves driving stability accordingly.

Another example is the left and right suspension.
One example is one that detects the length of the spring, corrects the target roll angle θ ₀ to minimize the difference between them, and performs posture control to achieve the target roll angle θ ₀ .

"Effects of the Invention" The present invention provides a vehicle height adjusting means for adjusting the vehicle height on the left and right sides of the vehicle body, a minimum vehicle height detection means for detecting when the vehicle height on the left and right sides of the vehicle body has reached the lowest controllable position, and vehicle speed detection means for detecting speed; acceleration detection means for detecting lateral acceleration applied to the vehicle body; and when the vehicle speed obtained by the vehicle speed detection means is equal to or higher than a predetermined value, the left and right wheels are detected based on the acceleration obtained by the acceleration detection means. The target roll angle is calculated to roll the vehicle body in the opposite direction to the roll direction caused by centrifugal force in order to approximately equalize the load sharing, and the target roll angle is calculated so that the vehicle body is maintained in a horizontal position when the vehicle speed is less than a predetermined value. 0, and the vehicle height on the side opposite to the lateral acceleration is set to the lowest height detected by the minimum vehicle height detection means to achieve the target roll angle. The present invention provides a vehicle body posture control device characterized by comprising a control means for controlling a high adjustment means, and thereby reduces and suppresses the bias of load distribution to the outside of a curve when the vehicle turns. The attitude of the vehicle is controlled, and the vehicle height on the inside of the turn is always maintained at the lowest controllable height. Therefore, it is possible to significantly improve the running stability of the car when turning, and
Since the vehicle body is controlled to maintain a horizontal posture below a predetermined safe speed, the vehicle does not force the driver to take an unreasonable posture and provides a great sense of driving stability both psychologically and in terms of operability.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a vehicle body posture control device according to an embodiment of the present invention, Fig. 2 is an explanatory diagram of the installation of a vehicle height adjustment means and a roll angle sensor on the right rear wheel of an automobile, and Fig. 3 is a diagram showing vehicle height adjustment. 4 is an explanatory diagram of the configuration of the roll angle sensor, FIGS. 5 a to 5 e are a flowchart of the operation of the vehicle body attitude control device shown in FIG. 1, and FIG. 6 is shown in FIG. 1. FIG. 7 is a schematic diagram for explaining the movement of the vehicle body T of an automobile having a vehicle body attitude control device, and shows a state in which there is no centrifugal force; FIG. Fig. 6 is a diagram corresponding to the movement of the vehicle body T in a state where it is not rotated, Fig. 8 is a diagram equivalent to Fig. 6 in a state where the target roll angle θ ₀ = 0 is achieved when centrifugal force is applied, and Fig. 9 is a diagram equivalent to centrifugal force. Figure 6 is a diagram equivalent to achieving attitude control that causes the vehicle to roll in the opposite direction when a force is applied, Figure 10 is a schematic diagram of the exterior of the vehicle in the state shown in Figure 9, and Figure 11 is a conventional vehicle when turning. 12 is a diagram corresponding to FIG. 6 in a conventional automobile, and FIG. 13 is a diagram corresponding to FIG. 6 in the state of FIG. 11. Explanation of symbols, 1...Vehicle body attitude control device, 2a, 2
b, 2c, 2d...Vehicle height adjustment means, 3...Vehicle speed sensor (vehicle speed detection means), 4...Steering sensor, 5...
Microcomputer system, 6a, 6b...base height switch, 7a, 7b...roll angle sensor,
11a...Hydraulic cylinder, 12a...Suspension spring.

Claims (1)

[Claims] 1 Vehicle height adjustment means for adjusting the vehicle height on the left and right sides of the vehicle body;
Minimum vehicle height detection means for detecting when the left and right vehicle heights of the vehicle body have reached the lowest controllable position; vehicle speed detection means for detecting vehicle speed; acceleration detection means for detecting lateral acceleration received by the vehicle body; and said vehicle speed. When the vehicle speed obtained by the detection means is equal to or higher than a predetermined value, the purpose is to roll the vehicle body in a direction opposite to the roll direction caused by centrifugal force in order to approximately equalize the load sharing between the left and right wheels based on the acceleration obtained by the acceleration detection means. A target roll angle calculation means for calculating a roll angle and setting the target roll angle to 0 so as to maintain the vehicle body in a horizontal position when the vehicle speed is less than a predetermined value; A vehicle body attitude control device comprising a control means for controlling the vehicle height adjustment means so as to achieve the target roll angle at the lowest height detected by the minimum vehicle height detection means.