JPH0347714B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle height determination device that detects an accurate vehicle height by determining whether the vehicle height of a vehicle or the like detected using ultrasonic waves is appropriate.

[Prior art]

Conventional vehicle height judgment devices include, for example, an ultrasonic vehicle height detector installed at the front of a vehicle that detects the time it takes to transmit ultrasonic waves to the road surface and receive the reflected waves. The vehicle height value is determined by multiplying the detection time by the ultrasonic speed, the average value of the vehicle height is calculated using a predetermined number of vehicle height values detected in this way, and the average value is determined to be the vehicle height value. There is something I did.

However, since ultrasonic waves have the property of being absorbed by a medium such as fresh snow and their intensity decreases, ultrasonic vehicle height detectors are not equipped with ultrasonic vehicle height detectors that detect On roads with a high absorption rate, the intensity of the received reflected waves is low, and there is a particular problem in that accurate vehicle height cannot often be detected using ultrasonic waves with such low intensity. Therefore, when using an ultrasonic vehicle height detector having the above-mentioned problem, the following two types of determination methods can be considered as methods for calculating the vehicle height average value when the vehicle height cannot be detected.

That is, the first method is to estimate that the vehicle height will not change when the intensity of the received reflected wave is low, use the previously detected vehicle height value as is, and add the estimated vehicle height value to a predetermined number of vehicle height values. The second method is to calculate the average value based on the vehicle height value.The second method is to calculate the average value based on a predetermined number of vehicle height values including the number of times the vehicle was not detected. This method calculates the average value using only the vehicle height value.

A vehicle height value is determined based on the vehicle height value calculated by such an average value calculation method, and the damping force and spring constant of the suspension device are switched to suppress bottoming, rolling, etc. of the vehicle.

[Problem that the invention seeks to solve]

However, in the case of conventional vehicle height judgment devices based on the average value calculation method, the previously detected vehicle height value is estimated as the new detected value and used as is, or only the vehicle height value detected within a predetermined number of detections is used. Since the average value is calculated using If an apparent vehicle height value that is different from the vehicle height value is detected, or if the detected vehicle height value is outside the allowable range that can be used as the actual vehicle height value, such as when passing through a ditch or road joint, noise may occur. The error in the average value increases due to the existence of vehicle height detection values that are affected by such factors as the above. In the first conventional example, if the estimated vehicle height value is equal to that affected by noise or the like, the error in the average value becomes even larger. As a result, in such a case, there is a problem that the detection accuracy of the vehicle height value deteriorates.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle height determination device that can detect a vehicle height value with good accuracy even when a vehicle height detection value is affected by noise or the like.

[Means for solving problems]

In order to achieve such an objective, the invention related to this application outputs a vehicle height detection signal according to the vehicle height based on the time from the time when ultrasonic waves are emitted toward the road surface until the reflected waves are received. A vehicle height detector that
The detection signal of the vehicle height detector is input, and it is determined whether the intensity of the reflected wave is below a predetermined value and whether the detected vehicle height value is within a predetermined setting range, and at least the intensity of the reflected wave is determined. is below the predetermined value or the detected vehicle height value is outside the predetermined setting range, abnormal state determining means for determining that the detection signal of the vehicle height detector is in an abnormal state, and the abnormal state Vehicle height detection value updating means that updates and stores a predetermined number of vehicle height detection values when the judgment result of the judgment means is in a normal state, and stops updating when the judgment result is in an abnormal state; and a predetermined number of the vehicle height detection value updating means. The present invention is characterized by comprising a vehicle height value determining means for determining a vehicle height value by averaging the stored values.

[Effect]

This invention detects the height value of a vehicle and the intensity of the received reflected waves using a vehicle height detector using ultrasonic waves, and determines whether the intensity of the reflected waves is greater than a predetermined reference value or detects the vehicle height. It is determined whether the value is within a predetermined set value range, and if the intensity of the reflected wave is less than a predetermined value or the vehicle height detection value is outside the predetermined reference range, the vehicle A high detection value is determined to be abnormal.

When the intensity of the received reflected wave is less than a predetermined value, the ultrasonic absorption rate is large and the vehicle height value cannot be detected correctly, and the detected vehicle height value is within the predetermined tolerance range that can be used as the actual vehicle height. If it is not, it cannot be used as the actual vehicle height value because it is affected by noise etc.

Vehicle height detection values that are determined to be abnormal are not imported.
The current vehicle height value is determined based on a predetermined number of previously detected vehicle height values that are not abnormal.

Therefore, by eliminating the apparent vehicle height value that differs from the actual vehicle height value due to weak reflected waves, inaccurate vehicle height values, noise, and shadow detection caused by passing through a ditch, etc., we can reduce the accuracy of the estimated vehicle height value. Even when the number of vehicle height values that can be adopted is small, such as when driving on a snow-covered road covered with fresh snow, the vehicle height value can be measured with high reliability.

〔Example〕

The present invention will be explained below based on illustrated embodiments.

FIG. 2 is a schematic configuration diagram showing an embodiment of this invention, FIG. 3 is a block diagram showing an embodiment of this invention, and FIG. 4 is a flowchart showing a processing procedure of a control device applicable to this invention. It is.

First, to explain the configuration, in Figure 2, 1
a, 1b are front wheels, 1c, 1d are rear wheels, 2a to 2d
is a damping force variable shock absorber inserted between each of the wheels 1a to 1d and the vehicle body 3; 4 is a variable damping force shock absorber inserted between the vehicle body 3;
This is an ultrasonic vehicle height detector located on the lower front surface of the vehicle.

Further, 5 is a variable damping force shock absorber 2.
This is a control device that controls damping forces a to 2d, and this control device 5 receives a vehicle speed detection signal from a vehicle speed detector 6 in addition to a detection signal from an ultrasonic vehicle height detector 4.
DV and the steering angle detection signal Dθ from the steering angle detector 7
and a switching signal CH from the changeover switch 8 are respectively supplied, and the damping force of each variable damping force shock absorber 2a to 2d is switched based on these detection signals.

The variable damping force shock absorbers 2a to 2d may, for example, have two fluid chambers defined within a cylinder tube, and a piston that is fixed to a piston rod and moves together with the piston rod, with a passage area that communicates between the two fluid chambers. Variable aperture that can be changed to 3 stages,
The configuration includes an electric motor that rotationally drives this variable diaphragm to change the passage area, and the output of the excitation current to the electric motor is switched in three stages using an excitation current as a control signal output from the control device 5. , the damping force can be controlled in three stages: high, medium, and low.

The ultrasonic vehicle height detector 4 includes an ultrasonic transmitter 4a that transmits ultrasonic waves, and an ultrasonic receiver 4b that receives reflected waves of the ultrasonic waves transmitted from the ultrasonic transmitter 4a and reflected on the road surface. It measures the time from when the ultrasonic transmitter 4a transmits the ultrasonic wave until the ultrasonic receiver 4b receives the reflected wave from the road surface, and the ultrasonic wave is measured in the required time. A vehicle height detection signal DH corresponding to the vehicle height that represents the relative distance between the road surface and the vehicle body obtained by multiplying the speed of the sound wave, and a reflected wave detection signal DR corresponding to the intensity of the reflected wave at the time of wave reception.
Outputs .

Further, the vehicle speed detector 6 outputs a detection signal DV according to the vehicle speed V of the vehicle, and the steering angle detector 7 outputs a detection signal Dθ according to the steering angle θ during steering. Furthermore, the changeover switch 8 is a switch for switching the damping force of the variable damping force shock absorbers 2a to 2d between automatic control and manual control, and is switched by the passenger's manual operation to signal the switching signal CH.
Outputs the rotation value "1".

Furthermore, as shown in FIG. 3, an example of the control device 5 includes an interface circuit 10, an arithmetic processing unit (CPU) 11 having two control timers 11a and 11b, and a storage device 12 such as RAM or ROM.
It is composed of a microcomputer 9 having the following functions. Then, the vehicle height detection signal DH and the reflected wave detection signal DR of the ultrasonic vehicle height detector 4 and the vehicle speed detector 6 are connected to the input side port of the interface circuit 10.
The vehicle speed detection signal DV of the steering angle detector 7, the steering angle detection signal Dθ of the steering angle detector 7, and the switching signal CH of the changeover switch 8 are respectively supplied, and an output circuit 13 is connected to the output side port.

Based on the control signal CS output from the microcomputer 9, the output circuit 13 compares the motor position with the rotational speed value and outputs a drive current to rotate the electric motor to a predetermined rotational position. As a result, the damping force of the variable damping force shock absorbers 2a to 2d is controlled to be switched to three levels: high, medium, and low damping force in accordance with the control signal.

The arithmetic processing unit 11 processes the vehicle height detection signal DH and reflected wave detection signal DR from the ultrasonic vehicle height detector 4 and the vehicle speed detection from the vehicle speed detector 6 according to a processing program stored in advance in the storage device 12. signal DV
, the steering angle detection signal Dθ from the steering angle detector 7,
The control signal CS, which executes a predetermined calculation process based on the changeover signal CH from the changeover switch 8 and controls the damping force of the variable damping force shock absorbers 2a to 2d to the optimum state according to the driving condition of the vehicle, is sent to the interface. It is output from the ace circuit 10 to the output circuit 13.

The storage device 12 of the control device 5 stores processing programs necessary for the arithmetic processing device 11 to execute arithmetic processing, and the processing results of the arithmetic processing device 11 are stored in a predetermined location in the storage device 12. It is sequentially updated and stored in the storage area.

Next, the processing procedure of the arithmetic processing unit 11 will be explained according to the flowchart of FIG.

The arithmetic processing unit 11 executes, for example, every 20 msec, as shown in FIG. The arithmetic processing is executed according to the timer interrupt processing program. This arithmetic processing is started only when it is determined in step a that the switching signal CH=0 (when the changeover switch is switched to automatic control).

That is, in step, the vehicle height detection signal DH and the reflected wave detection signal DR of the ultrasonic vehicle height detector 4 are read, and these are used as the vehicle height detection value H and the reflected wave detection value R.
The data is temporarily stored in a predetermined storage area of the storage device 12 as a file.

Next, the process moves to step, and it is determined whether the intensity of the reflected wave based on the detected reflected wave value R is greater than a predetermined value S set in advance. In this case, the determination is made by looking at the strength of the reflected waves to determine whether or not there is an abnormal condition such as a snow-covered road where a medium such as fresh snow that has a high absorption rate for ultrasonic waves is on the road surface.

At this time, if the result of the determination is that the reflected wave detection value R is larger than the predetermined value S, R≧S, the process moves to step. In this step, the storage device 1 is
Read out the high vehicle height reference value Hmax and low vehicle height reference value Hmin stored in the reference vehicle height value storage area of 2.
The vehicle height detection value H based on the vehicle height detection signal DH is compared with both reference values Hmax and Hmin to determine whether the vehicle height detection value H is within a predetermined range between the two reference values.

In this case, the determination is made as to whether or not the vehicle height detection value H is in an abnormal state that is out of the range that is considered to be the normal state of the vehicle. For example, when the height of the detected vehicle height H is outside the range that is considered to be the normal state of the vehicle, for example, when the height of the groove bottom, which is not the road surface, is detected after passing through a groove. , or when detecting the height to the top of a temporary protrusion, etc., this is done to determine whether the detected vehicle height value H is a value that can actually be taken.

The above steps are shown in FIG. The estimated vehicle height value (× ), as shown in Figure 6,
The actually detected vehicle height value and the apparent vehicle height value are extracted. Next, in step, the apparent vehicle height value (● mark) is removed, and only the vehicle height value H that is actually detected and has a high degree of certainty that can be adopted as the vehicle height value is extracted.

In the above step, the result of car height judgment is
When Hmax≧H≧Hmin, the process moves to the vehicle height value determination process from step to step.

In the vehicle height value determination process, first, in step, the actually detected vehicle height detection values Hi are sequentially updated and stored in n predetermined vehicle height value storage areas of the storage device 12 to rewrite the contents. Next, the process moves to step, where the vehicle height detection signal DH is processed by a low-pass filter, and a predetermined number f(H ₀ ,
A current vehicle height value HF is calculated by averaging H ₁ , .

Next, the process moves to a step where a predetermined number f (HF ₀ , HF ₁ , . . .
...HFm: For example, m = 10 pieces) is averaged to calculate the average vehicle height value HA, and the average vehicle height value HA
is updated and stored in a predetermined storage area of the storage device 12.
This completes the vehicle height value determination process, and the vehicle bottoming determination process is performed in the next steps based on the current vehicle height value HF and the average vehicle height value HA.

In the bottoming judgment process, first, in step, the current vehicle height value HF stored in step and the average vehicle height value HA stored in step are read respectively, and the difference value obtained by subtracting the current vehicle height value HF from average vehicle height value HA ( The absolute value of HA−HF) is
It is determined whether the vertical vibration of the vehicle, which is stored in advance in a predetermined storage area of the storage device 12, is larger than a reference setting value δ.

At this time, if the judgment result is that the amplitude of the vertical vibration of the vehicle is large |HA-HF|≧δ, the process moves to step and an initial value is preset to the bottoming control timer 11a provided in the arithmetic processing unit 11. After that, the rolling determination process of the vehicle is performed in the following steps.

Further, in the step, if it is determined that the intensity R of the reflected wave is weaker than the predetermined value S (R<
S) or in the step, the vehicle height detection value H
is determined not to be within the specified range (Hmax<
If H or H<Hmin), the process moves to step to perform the vehicle rolling judgment process without performing the vehicle height judgment process or the bottoming judgment process.

These steps and step determinations are to check whether the detected vehicle height value H can be adopted as the actual vehicle height value, and as mentioned above, when the intensity R of the reflected wave is weaker than the predetermined value S, This is to exclude cases where the detected vehicle height value H is too large and has low reliability from the standard for calculating the average value. Therefore, in these cases, control using the newly detected vehicle height value is stopped without reading the vehicle height detection signal DH, and the previous judgment result based on the previous vehicle height detection value H is not changed. Do it like this.

Furthermore, in the step, the average vehicle height HA
If the absolute value of the difference value (HA - HF) between the vehicle height value H and the current vehicle height value HF is smaller than the vehicle bottoming reference value δ (|HA - HF|<δ), that is, the amount of change in the vehicle height value H is less than the reference value δ. Even when it is determined that the vehicle is not in the bottoming state because the vehicle is small, the process moves to the rolling determination process from step to step.

In the rolling judgment process, first, in step, the steering angle detection signal Dθ is read and, for example,
The steering angle is calculated by measuring the number of pulses from the steering neutral position when the vehicle is moving straight, and is temporarily stored in a predetermined storage area of the storage device 12 as the steering angle detection value θ. Next, the process moves to step to calculate the amount of change in steering angle Δθ per unit time, and temporarily stores this amount of change in steering angle Δθ in a predetermined storage area of the storage device 12.

Next, move to the step to output the vehicle speed detection signal.
The vehicle speed is calculated by reading the DV, for example, by measuring the number of pulses per unit time, and temporarily storing this as the vehicle speed detection value V in a predetermined storage area of the storage device 12. Next, the process moves to step 〓, in which a table previously stored in a predetermined storage area of the storage device 12 is referred to in order to determine the magnitude of rolling.
A roll judgment constant α corresponding to the detected vehicle speed value V is calculated, and then the process moves to step.

In the step, the steering angle change amount Δθ stored in a predetermined storage area of the storage device 12 in the step is read out, and it is determined whether the steering angle change amount Δθ is larger than the roll determination constant α. If the result of the determination is a rolling state in which Δθ≧α, the process moves to step, presets the roll control timer 11b provided in the storage device 12 to an initial value, and then adjusts the damping force from the next step to step. The damping force of the variable shock absorbers 2a to 2d is
A damping force determination process is performed to determine whether to set high, medium, or low damping force.

In addition, in the step, the judgment result is
If Δθ<α and it is determined that the vehicle is not in a rolling state, the process moves to step and the subsequent damping force determination process is performed.

In the damping force judgment process, first, in step, a low damping force command signal for controlling the variable damping force shock absorbers 2a to 2d of all wheels 1a to 1d to the minimum damping force SO is stored in the damping force control storage area of the storage device 12. , and then move on to the step.

In the step, the count value of the bottoming control timer 11a preset in the step is read out, and it is determined whether or not the bottoming control timer 11a has timed up. At this time, timer 11
If a is before the time-up, the process moves to step, counts down the contents of the timer 11a by "1", and then moves to step.
In step, a medium damping force command signal for controlling each of the variable damping force shock absorbers 2a to 2d to medium damping force ME is updated and stored in the damping force control storage area, and then the process moves to step.

Further, in step, when the bottoming control timer 11a has timed up, it is determined that vehicle bottoming has not occurred, and
Move to step.

In the step, the count value of the rolling control timer 11b preset in the step is read out, and it is determined whether the rolling control timer 11b has timed up. At this time, timer 11
If b is before the time-up, the process moves to step, counts down the contents of the timer 11b by "1", and then moves to step.
Then, in step, a high damping force command signal for controlling each of the variable damping force shock absorbers 2a to 2d to a high damping force HD is updated and stored in the damping force control storage area, and then the process moves to step.

Further, in step, if the rolling control timer 11b has timed up, it is determined that rolling is not occurring in the vehicle, and the process proceeds to step.

In this step, the damping force of the variable damping force shock absorbers 2a to 2d is set to low, medium, or high damping based on any of the damping force command signals finally stored in the damping force control storage area of the storage device 12. A control signal CS for controlling the output power is outputted to the output circuit 13 via the interface circuit 10. As a result, the variable damping force shock absorbers 2a to 2d
The electric motor is rotationally driven, and the damping force of the variable damping force shock absorbers 2a to 2d is controlled to either low, medium or high damping force.

Here, the step process constitutes an abnormal state determining means that determines the abnormal state of the detection signal based on the strength of the reflected wave, and the step process determines the abnormal state of the detection signal based on the height of the vehicle height value. Further, the step-by-step processing constitutes a vehicle height value determining means. Note that the determination of the abnormal state may be performed only in one of the steps.

Next, the effect will be explained.

Currently, the vehicle is traveling normally, and a predetermined number n of vehicle height detection values H ₁ to _{H o} are stored in the vehicle height detection value storage area of the storage device 12, and the current vehicle height detection value is stored in the predetermined storage area. It is assumed that the high value HF and the average vehicle height value HA are each stored.

In this state, when the vehicle is driving on a normal road surface with normal ultrasound reflection and no grooves, etc.
Since the value H of the vehicle height detection signal DH output from the vehicle height detector 4 is within the predetermined setting range, and the value R of the reflected wave detection signal DR is greater than or equal to the reference value S, the arithmetic processing unit When the timer interrupt process shown in FIG. 4 is executed in step 11, the vehicle height detection signal DH and the reflected wave detection signal DR are first read in step 11, and these are set as the vehicle height detection value H and the reflected wave intensity detection value R. It is temporarily stored in a predetermined storage area of the storage device 12.

Next, the process moves to step, but since the reflected wave intensity detection value is greater than the predetermined reference value S, the process moves to step, and in this step too, the vehicle height detection value H is
Since Hmax≧H≧Hmin, the process moves to step to step vehicle height value determination processing.

In this vehicle height value determination process, first, in step, the vehicle height value data list in the storage device 12 is updated and stored, and then, in step, the vehicle height values Hi stored in the vehicle height value data list are averaged by low-pass filter processing to determine the current vehicle height value. The HF is calculated and updated to the current vehicle height value storage area of the storage device 12.
Next, the process moves to step, reads a predetermined number of current vehicle height values HFi stored in the current vehicle height value storage area, averages them to calculate an average vehicle height value HA, and updates and stores this in the average vehicle height value storage area. do.

In this way, by determining the current vehicle height value based on a predetermined number of actually detected vehicle height values H, the vehicle height detection values H are averaged to determine a more accurate vehicle height value. I can do it.

When driving on a normal road surface described above changes to driving on a road surface covered with fresh snow, the ultrasonic waves emitted from the vehicle height detector 4 are absorbed by the fresh snow, or their intensity is weakened by diffuse reflection from the fresh snow, so that the ultrasonic waves are reflected. Since the intensity value R of the wave detection signal DR is less than the reference value S, it is determined that the vehicle height detection value H cannot be actually adopted, and the process moves to step.

In addition, when the vehicle height detector 4 passes over irregularities such as road joints, manholes, and steps that exceed the predetermined set value range of the vehicle height detection value while driving on the above-mentioned normal road surface, or when noise from other equipment is detected. When the vehicle height detection signal is
Since the vehicle height value H of DH is outside the predetermined setting value range,
It is determined that the detected vehicle height value H cannot actually be used, and the process moves to step.

In this way, if R<S in the step,
Or, in the step Hmax<H or H<
If it is Hmin, the process moves to step 5 to avoid changing the determination result based on the previous vehicle height detection value without reading the new vehicle height detection value H. As indicated by the cross mark, the current vehicle height detection value is not estimated to be the same as the previous vehicle height detection value due to the inability to detect the vehicle height.
As shown by the circle in FIG. 6, the vehicle height average value calculated only from the actually detected vehicle height detection values can be adopted as the actual vehicle height value. Furthermore, as shown by the ● mark in the same figure, vehicle height detection values that cannot be used as vehicle height values are removed when calculating the average value, making it possible to determine extremely accurate vehicle height values.

Note that even if the apparent vehicle height value is affected by the noise mentioned above, if it is within the range of Hmax≧Hmin, it will not be removed in the step, but if it is within this range, the above-mentioned apparent height value will be reduced by the averaging process. Errors based on the vehicle height value can be sufficiently prevented.

Based on the vehicle height value determined as described above, the damping force or spring constant of the suspension device using variable damping force shock absorbers 2a to 2d, for example, less than a step, is controlled to reduce vertical vibration of the vehicle. (bottoming), rolling, etc. are suppressed, and ride comfort is improved.

This damping force control first subtracts the vehicle height average value HF from the vehicle height determination value HA in step,
It is determined whether the absolute value of the difference value is larger than a predetermined value δ for determining bottoming, and based on the determination result, if |HA−HF|≧δ, the process moves to step and the calculation is performed. An initial value is preset in the bottoming control timer 11a of the processing device 11, and on the contrary, when there is no bottoming state where |HA-HF|<δ, the process moves to step and moves to the rolling judgment process from step to step. do.

In the rolling judgment process, based on the vehicle speed value V based on the vehicle speed detection signal DV from the vehicle speed detector 6 and the steering angle θ based on the steering angle detection signal Dθ from the steering angle detector 7, if Δθ≧α, the process moves to step. Then, an initial value is preset in the roll control timer 11b, and on the other hand, when there is no rolling state where Δθ<α, the process moves to step and moves to the damping force judgment process of step to step.

In the damping force determination process, the damping force of the variable damping force shock absorbers 2a to 2d is determined as high, medium, or low based on the detected vehicle speed value H and the detected steering angle value θ, and the damping force is determined in steps. The electric motor is rotationally driven to control the opening degree of the variable aperture so that the damping force of the variable force shock absorbers 2a to 2d is set to high, medium, or low damping force.

In this way, based on the vehicle speed V and the steering angle displacement amount θ, the variable damping force shock absorbers 2a to 2d
By controlling the damping force to a low, medium, or high damping force, it is possible to improve the driving stability, riding comfort, etc. of the vehicle.

〔Effect of the invention〕

As explained above, in this invention, the vehicle height value of the vehicle and the intensity of the received reflected wave are detected by a vehicle height detector using ultrasonic waves, and whether the intensity of the reflected wave is greater than or equal to a predetermined reference value is detected. and whether the vehicle height detection value is within a predetermined setting range, and if the intensity of the reflected wave is less than a predetermined value or is affected by noise etc., the vehicle height detection value is adopted as the actual vehicle height value. If the vehicle height detection value is not within a predetermined allowable range, the vehicle height detection value is determined to be abnormal, and if it is determined to be normal, a predetermined number of vehicle height detection values are updated and stored, and the vehicle height detection value is determined to be abnormal. When the determination is made, updating of the detected vehicle height value is stopped and a predetermined number of stored vehicle height detected values are averaged to determine the vehicle height value at that time. Therefore, even when the reflected waves become weak and the number of vehicle height detection values that can be used as the vehicle height value decreases, such as when driving on a snowy road covered with fresh snow,
To eliminate these influences even when measuring an apparent vehicle height value that differs from the actual vehicle height due to the effects of noise, passage through a groove, etc., and to adopt a highly reliable vehicle height value by performing averaging processing. I can do it.

Therefore, by switching the damping force and spring constant of the suspension device using the vehicle height determination device of the present invention, bottoming, rolling, etc. of the vehicle can be effectively suppressed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of this invention, FIG. 2 is a configuration diagram showing a schematic configuration of this invention,
FIG. 3 is a block diagram showing an embodiment of this invention.
FIG. 4 is a flowchart showing the processing procedure of the control device, FIG. 5 is a graph showing the vehicle height value detection state, and FIG. 6 is a graph showing the vehicle height value sampling state. 1a to 1d...wheels, 2a to 2d...variable damping force shock absorber, 3...vehicle body, 4...ultrasonic vehicle height detector, 5...control device, 6...vehicle speed detector, 7...steering Angle detector, 9...Microcomputer, 10...Interface circuit, 11...
Conversion processing circuit, 11a...bottoming control timer, 11b...rolling control timer, 12...
Storage device, 13...output circuit.

Claims (1)

[Scope of Claims] 1. A vehicle height detector that outputs a vehicle height detection signal according to the vehicle height based on the time from when ultrasonic waves are emitted to the road surface to when the reflected waves are received; The detection signal of the detector is input, and it is determined whether the intensity of the reflected wave is below a predetermined value and whether the detected vehicle height is within a predetermined setting range. abnormal state determining means for determining that the detection signal of the vehicle height detector is in an abnormal state when the detected vehicle height value is below the predetermined setting range or when the detected vehicle height value is outside the predetermined setting range; Vehicle height detection value updating means that updates and stores a predetermined number of vehicle height detection values when the determination result is in a normal state, and stops updating when the determination result is in an abnormal state; and a predetermined number of stored values of the vehicle height detection value update means. A vehicle height determination device comprising: vehicle height value determining means for determining a vehicle height value by averaging the vehicle height values. 2. The vehicle height value determining means includes a first averaging means that processes a predetermined number of vehicle height values stored in the vehicle height value updating means and averages them using a low-pass filter; 2. The vehicle height determination device according to claim 1, further comprising a second averaging means that performs low-pass filter processing and averaging.