JPH0478645A - Bad road judging device for vehicle with antilock brake system - Google Patents

Abstract

PURPOSE:To perform the appropriate judgment of a bad road even during ABS control compared to the non-executed time of ABS control, and allowing the reference value to be changed according to the vehicle speed only at the non-executed time of ABS control. CONSTITUTION:A bad road judging device for a vehicle with ABS is provided with a wheel acceleration detecting means 400 for detecting the acceleration of wheels from the output of a wheel speed detecting means 300, and a reference value setting means 500 for setting the reference value of wheel acceleration for the judgment of a bad road. When the fluctuation of detected acceleration exceeding the reference value is generated more frequently than the set frequency within the set time, the bad road judging means 200 judges a travel road to be a bad road. The reference value of the bad road judging means 200 is made larger in the case of ABS control being performed compared to the non-executed case of ABS control. A reference value changing means 700 is further provided to change the above-mentioned reference value according to the vehicle speed only at the non-executed time of ABS control. The judgment of a bad road can be thus performed appropriately.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a vehicle equipped with an ABS (anti-skid brake system), in which the wheel speed (rotational speed of the wheels) is
The present invention relates to a rough road determining device that determines whether or not a road surface is a rough road based on a change in the road surface.

(Prior Art) In various types of control such as vehicle traction control and ABS control (anti-skid control), in order to perform more appropriate control, for example, the content of control is changed depending on whether the road surface is rough or not. It is possible to do so.

As a rough road determining device for determining whether such a road surface is rough, a device described in Japanese Patent Application Laid-Open No. 63259132 is known.

This disclosed device detects periodic fluctuations in wheel acceleration on a rough road, determines whether the traveling road is a rough road based on the number of times this periodic fluctuation occurs within a predetermined period, and based on the result. traction control or ABS control.

(Problems to be Solved by the Invention) ABS control is performed to prevent excessive braking force from acting on the wheels during braking, which would lead to a locked state of the wheels, which would actually reduce the braking effect. The braking force of the wheels is controlled so that the slip ratio of the wheels converges to a preset target slip ratio. For this purpose, in ABS control, the hydraulic pressure of the brake system is controlled to periodically relieve the braking force on the wheels.

That is, ABS control is performed by a method that generates periodic acceleration fluctuations of the vehicle body.

Therefore, if rough road judgment is performed based on the periodic acceleration fluctuations as described above, there is a risk of confusion with acceleration fluctuations caused by ABS control, and it is not possible to properly judge rough roads during ABS control. The problem is that it disappears.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a rough road determination device for a vehicle with ABS that can properly determine rough roads even during ABS control.

(Means for Solving the Problems) According to a first feature of the present invention, the rough road determination device for a vehicle with ABS of the present invention includes a wheel speed detecting means for detecting the speed of a wheel, and a wheel speed detecting means for detecting the speed of a wheel. wheel acceleration detection means for detecting wheel acceleration based on the wheel acceleration; reference value setting means for setting a reference value of wheel acceleration for determining rough road; and said reference value of the acceleration detected by said wheel acceleration detection means. a rough road determining means that determines that the traveling road is a rough road when a fluctuation exceeding a predetermined number of times occurs within a certain time;
When ABS control is being performed, the reference value in the rough road determining means is made larger than when ABS control is not being performed, and only when ABS control is not being performed, the reference value is adjusted according to the vehicle speed. and a reference value changing means for changing the reference value.

The rough road determination is intended to effectively perform traction control or ABS control depending on the condition of the road surface on which the vehicle is traveling. However, when focusing only on traction control, as the vehicle speed increases, there is little demand to perform rough road correction to further improve the driving effect.On the other hand, when the vehicle speed is low, it is necessary to perform rough road correction as much as possible to improve the driving effect. It is preferable to increase According to a preferred embodiment of the invention, ABS
When control is not being performed, the value of the reference acceleration for rough road determination is changed depending on the vehicle speed. In this case, preferably, as the vehicle speed increases, the reference acceleration for determining the rough road is also set to be large.

According to the second feature of the present invention, there is provided a set number changing means for increasing the set number of times in the rough road determining means when ABS control is being performed compared to when ABS control is not being performed. It will be done.

According to a third feature of the present invention, there is provided a driving wheel speed detecting means for detecting the speed of the driving wheel, a driven wheel speed detecting means for detecting the speed of the driven wheel, the driving wheel speed detecting means and the driven wheel speed detecting means. a slip ratio calculation means for calculating a slip ratio of the driving wheels based on a detected value from the means; a target slip ratio setting means for setting a target slip ratio for traction control;
traction control means for controlling engine output or braking force so that the slip ratio converges to the target slip ratio; , traction changing means for increasing the target slip ratio is provided.

According to a fourth feature of the present invention, there is provided an ABS target slip ratio setting means for setting a target slip ratio for ABS control, and an ABS control means for controlling braking force so that the slip ratio converges to the target slip ratio. and an ABS that reduces the ABS target slip ratio when the traveling road is determined to be a rough road by the rough road determining means.
Modification means are further provided.

(Function) According to the present invention, it is determined that the traveling road is a rough road when a change in the acceleration detected by the wheel acceleration detection means that exceeds a predetermined reference acceleration occurs more than a set number of times within a certain period of time. When ABS control is performed, compared to when ABS control is not performed,
Increase the reference value of acceleration.

In this case, the reference value is raised to such an extent that it is not affected by acceleration fluctuations caused by ABS control.

Furthermore, in a preferred embodiment, when ABS control is not performed, the value of the reference acceleration for determining rough road is changed according to the vehicle speed, and as the vehicle speed increases, the reference acceleration for determining rough road is also set to be larger. be done. Thereby, rough road judgment can be made more appropriately.

When ABS control is being performed, the set number of times for counting the number of times fluctuations exceeding the above reference value have occurred for rough road judgment is increased compared to when ABS control is not being performed. . In this case, the set number of times is increased to the extent that it is not affected by acceleration fluctuations caused by ABS control.

Further, if the road surface on which the vehicle is traveling is determined to be rough, the rough road is corrected so that the target slip rate for traction control is increased. As a result, high power transmission efficiency can be maintained depending on the road surface condition.

Further, if it is determined that the traveling road is a rough road, the target slip rate for ABS control is decreased. This allows effective ABS control to be performed regardless of road surface conditions.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Overview of the Inventive Structure Referring to FIG. 1, the basic structure of the present invention is schematically illustrated in block diagram form.

The rough road determination device for a vehicle with ABS according to the present invention includes a slip control means 100 that includes traction control, ABS control, etc. based on the slip ratio. Change control content according to input.

The rough road determining means 200 receives an input from the wheel acceleration detecting means 400 which obtains the wheel acceleration based on the detected value from the wheel speed detecting means 300, and sets a reference value for setting a reference value of the wheel acceleration for determining the rough road. Based on the human power from the means 500, it is determined whether the traveling road is a rough road or not. This standard value is
When the anti-skid brake device 600 is performing ABS control, the reference value changing means 700 changes it.

Outline of Vehicle Configuration FIG. 2 is a system diagram of a hydraulic circuit for controlling the engine and wheel brakes of a vehicle to which the traction control according to the present invention is applied.

Vehicle A has left and right front wheels, i.e. driven wheels IFL and IFR.
, and rear wheels, that is, drive wheels IRL and IRR.

An engine 2 is mounted on the front part of the vehicle body, an automatic transmission 3 is connected to the output side of the engine 2, and a propeller shaft 4 is connected to the output side of the automatic transmission 3. The output of the engine 2 is transmitted to the left and right drive wheels IRL and IR via a differential gear device 5 connected to the propeller shaft 4 and left and right drive shafts 6L and 6R.
transmitted to R.

Structure of Automatic Transmission The automatic transmission 3 includes a torque converter 11 and a multi-speed gear mechanism 12 that provides a plurality of gears. Furthermore, the multi-speed gear mechanism 12 includes a plurality of solenoids 13a for switching the hydraulic circuit and providing a desired gear position.
It is equipped with The torque converter 11 also includes a lock-up clutch, and a solenoid 13b for controlling the operation of the lock-up clutch.

An automatic transmission control unit UAT is provided to control the solenoid 13a and the solenoid 13b. This automatic transmission control unit UAT stores a map for shift control and a map for lock-up control, and control unit OAT outputs control signals to solenoid 13a and solenoid 13b based on this map.
This occurs during the transmission and controls gear shifting and lock-up.

For this purpose, the control unit UAT receives a signal from a main throttle valve opening sensor 61 that detects the opening of the main throttle valve 43 and a subthrottle valve opening that detects the opening of the subthrottle valve 45. A signal from the sensor 62 and a signal from the vehicle speed sensor 63 that detects the vehicle speed (instead, a sensor that detects the rotational speed of the propeller shaft 40 can also be used).

Structure of Brake Oil Pressure Adjustment Mechanism A hydraulically operated brake system is provided for braking each wheel IFR to IRR. For this purpose, brakes 21FR to 21R are installed corresponding to each wheel IFR to IRR.
R is provided. Each of the brakes 21FR to 21RR includes calipers (brake cylinders) 22FR to 22RR, and brake hydraulic pressure is supplied to the calipers 22FR to 22RR via pipes 23FR to 23RR.

The brake system includes a brake pedal 25 into which a pedal force from an operator is input, a booster 26 that boosts the pedal force using a hydraulic booster, and a booster 26 that boosts the pedal force using a hydraulic booster.
A tandem-type master cylinder 27 connected to the cylinder 6 is provided. The master cylinder 27 has its first discharge port 27a connected to the left front wheel brake 21FL via the brake pipe 23FL, and its second discharge port 27b connected to the brake pipe 23
It is connected to the left front wheel brake 21FL and the right front wheel brake FR via the FR.

The booster 26 is connected to a pump 29 via a pipe 28 and receives pressure oil from the pump.

A return piping 30 is connected to the pump, and excess pressure oil is returned to the reservoir tank through this piping 30. A branch pipe 28a branches off from the pipe 28, and an electromagnetic on-off valve 32 is disposed in the branch pipe 28a.

A pipe 33 extends from the booster 26, and the pipe 33
An electromagnetic on-off valve 34 and a one-way valve 35 are provided in parallel with the on-off valve 34.

The branch pipe 28a and the pipe 33 merge at a position a on the downstream side, and a brake pipe 23RL for the left and right rear wheels is connected to this part.
, 23RR are connected.

Ionization on/off valves 36A, 37A are connected to the pipes 23RL, 23RR, respectively, and IJ-F passages 38L, 38 are connected downstream of the throttle valves 36A, 37A, respectively.
Electromagnetic on-off valves 36B and 37B are connected to R, respectively.

Similarly, electromagnetic on-off valves 36A' and 37A' are connected to the front wheel brake pipes 23FL and 23FR, respectively, and the IJ-F passages 38L' and 38R' are connected downstream of these 36A' and 37A', respectively. An electromagnetic on-off valve 36B'37B' is connected to each of them.

Engine generated torque adjustment mechanism An intake passage 41 communicates with the engine 2, and this intake passage 41 includes a main throttle valve 43 connected to an accelerator pedal 42, and a sub-throttle valve 43 connected to an actuator 44 for adjusting throttle opening. A throttle valve 45 is provided. In this case, since the main throttle valve 43 and the sub-throttle valve 45 are arranged in series, the overall opening of the throttle valves will match the smaller opening of the two.

Control unit U for traction control and ABS control
TR These valves 32.34.36A, 37A, 36B, 37
In order to control the operation of the actuator 44 of the sub-throttle valve 45 and the sub-throttle valve 45, a control unit UT'R for traction control is provided. That is, the control unit UTR controls the braking force of the wheels by controlling the engine output and brake oil pressure for the purpose of traction control.

The control unit (UTR) receives signals from wheel speed sensors 64 to 67 that detect the speed of each wheel, as well as a main throttle opening sensor 61 and a sub-throttle opening sensor 62.
, a vehicle speed sensor 63, an accelerator opening sensor 68, a yaw rate sensor 69, a shift sensor 70, a steering angle sensor 71, and a manually operated traction control mode selection switch 72.

The control unit (UTR) is a human interface that receives signals from each sensor mentioned above, as well as a CPU, ROM, and RA.
A microcomputer with M, an output interface, and valves 32, 34, 36A, 37A, 36B, 37
B, 36A', 37A', 36B', 37B' and a drive circuit for driving the actuator 44.

The ROM stores control programs and various maps necessary for traction control and ABS control, and also stores the RA
M is provided with various memories necessary for executing control.

Bad road judgment Next, the rough road determination procedure in this embodiment will be explained.

FIG. 3 is a flowchart showing the rough road determination procedure. In steps 1 and 2, the control unit UTR detects the left front wheel rotation speed WFL and the right front wheel rotation speed WFR. Next, in step 3, the left front wheel rotation speed WF
Based on L and the right front wheel rotational speed WFR, the rotational accelerations DWF L and DWFR of the left and right wheels are determined, respectively.

The left front wheel acceleration DWFL is obtained by subtracting the previous left front wheel speed WFL from the current left front wheel speed WFL.

DWF L=WF L, -WFL, -+This value is offset-corrected to find a reasonable left front wheel acceleration. That is, this offset correction is performed by subtracting the vehicle body acceleration from the wheel acceleration. In this case, in the above equation, the vehicle body acceleration is expressed as (WFL, , -WFL, , )/4. Since the vehicle body starts moving with a delay relative to the wheels, offset correction is performed taking this delay into consideration. The delay corresponds to approximately four cycles of the rough road determination flow in this embodiment (flow processing cycle: 14 m5 ec, delay with respect to the wheels of the vehicle approximately 55 m5 ec).

Therefore, in this example, the average of the actual wheel accelerations up to four cycles before the current time is used as the vehicle body acceleration.

The right front wheel acceleration DWFR is also calculated using the same procedure.

Next, the control unit (UTR) determines whether the timer AKRTM is greater than or equal to a predetermined value of 1, that is, whether a preset predetermined time (in this example, 0.7 seconds) has elapsed. If not, the absolute value of the left front wheel acceleration DWFL obtained in step 3 is the reference value T for determining the rough road.
It is determined whether the value is equal to or higher than HREG (step 5).

In this case, in this example, the control unit (UTR) has a reference value T for judging rough roads during ABS control and when not.
The value of HREG is changed.

Further, the reference value THREG is also changed depending on the vehicle speed.

When ABS control is in progress, the control unit (UTR) sets the reference value THREG to 1.50 g. When ABS control is not in progress and the vehicle speed is 80 km/h or more, the reference value THREG is set to 0.71 g, and when the vehicle speed is less than that, it is set to 0.57 g.

Next, the control unit (UTR) calculates the left front wheel acceleration DWFL.
Counter AKROL counts the number of times that exceeds the reference value THREG.
Count by. In this case, the counter AKROL counts only when a fluctuation in amplitude occurs such that the front left wheel acceleration DWFL exceeds both the positive and negative values of the reference value THREG (steps 6.7.8 and 9).

For example, when the left front wheel acceleration DWFL changes as shown in FIG. 4, the peak values shown at points a, b, and c each exceed the reference value THREG, so the control unit U
TR counts as 1.2.3 corresponding to these peak values.

However, as shown in Fig. 5, when the left front wheel acceleration DWFL changes, the peak value at point e is equal to the reference value THR.
Since the negative value of EG is not reached, the acceleration change in this cycle is not counted, and then 2 at the point g exceeding the negative value of the reference value THREG and 2 at the point g exceeding the positive value of the reference value THREG. will be counted.

The control unit) UTR counts the number of times that the right front wheel acceleration DWFR exceeds the reference value THREG using the counter AKROR (steps 10 to 1).
4). Then, the timer AKRTM is added (step 15) and the process returns to step 1.

In this example, the process in which steps 1 to 15 are one cycle is executed every 14 microseconds, so after 50 cycles, the determination in step 1 becomes YES, and the routine in step 16 is executed.

In the flow shown in FIG. 6, the control unit (UTR)
It is determined whether S control is in progress (step 17).

If this determination is YES, that is, if ABS control is in progress, the control unit (UTR) uses counters AKROL and ABS.
The value of KROR is determined, and both values are set to a predetermined value (in this example, 1
4 times), it is determined that the road is rough and the rough road correction is performed (steps 18 and 19). Specifically, this is done by changing the control conditions when performing traction control, ABS control, etc., such as the target slip ratio (
Step 20).

Also, if ABS control is not in progress, the above counter A
If the values of KROL and AKROR are determined and any value exceeds a predetermined value (in this example, 10 times) (steps 21 and 22), it is determined that the road is rough and rough road correction is performed.

After executing the process of FIG. 6 in step 16, the control unit UTR outputs the counters AKROL and AKR.
The value of OR and the timer ΔKRTM are reset (step 23). Therefore, in order for the rough road correction to be performed, the values of the counters AKROL and AKROR must be 0.7
It is necessary to reach a predetermined number of times within a certain period of time (seconds).

Slip Control Traction control and ABS are examples of slip control.
One example is control. Traction control enables efficient transmission of power from the drive wheels to the road surface.
This is to maintain the slip ratio at a desired value.

In the vehicle of this example, traction control includes slip rate engine control to obtain a desired slip rate by controlling the output of the engine 2, and control to obtain a desired slip rate by controlling the braking forces of wheels IRR and IRL. Consists of slip rate brake control to achieve this.

ABS control is performed to prevent the wheels from locking due to excessive braking force acting on them during braking, which would actually reduce the braking effect. The braking force is controlled so that it converges to a set target slip ratio. For this purpose, in ABS control, the hydraulic pressure of the brake system is controlled to periodically reduce the braking force on the wheels.

ABS control and traction control brake control are the same in that they control the braking force so that the slip ratio converges to a target value, but in ABS control, the traction control is controlled so that the braking force is periodically relieved. The difference is that the control is controlled to apply braking force.

Note that the target slip rates for the slip rate brake control and slip rate engine control described above are determined depending on, for example, the road surface friction coefficient μ, vehicle speed, accelerator opening, steering angle, and suspension driving mode such as sporty or hard. .

Next, the contents of the slip control by the control unit (UTR) will be explained based on FIG. 7.

In FIG. 7, the target slip rate for engine control of the drive wheels is indicated by SET, and the target slip rate for brake control of the drive wheels is indicated by SBT. Note that SBT is set to a larger value than SET.

Now, until time t1, there is no large slip in the drive wheels, so engine control is not being performed, and therefore the sub-throttle valve 45 is fully open, and the throttle opening (both throttle valves 43. 45, which matches the opening of the smaller throttle valve)
Tn corresponds to the main throttle opening TH-M, which in turn corresponds to the accelerator opening (the opening of the accelerator pedal, which is fully open when the accelerator pedal is fully depressed).

At time t1, when the slip rate of the driving wheels reaches the target slip rate SET for engine control, slip control by engine control is started, and by controlling the actuator 44 and closing the sub-throttle valve 45, the throttle opening degree Tn is increased. It is lowered all at once to the lower limit control value SM. After the throttle opening degree Tn is once set to SM, the opening degree TH-3 of the sub-throttle valve 45 is feedback-controlled so that the slip rate of the driving wheels becomes the target slip rate for engine control SET. When engine control is started in this way, the sub-throttle valve opening TH-3 becomes smaller than the main throttle valve opening TH・M, so the throttle opening Tn becomes the sub-throttle valve opening TH-3. .

If the engine control described above does not sufficiently reduce the slip ratio, the slip ratio will continue to increase and t
At time point 2, the target slip rate for brake control becomes equal to or higher than the target slip rate SET.

When the slip rate of the driving wheel becomes equal to or higher than the target slip rate SBT for brake control at time t2, the brake 21R of the driving wheel is activated.
Brake fluid pressure is supplied to R and 21RL, and slip control by both engine control and brake control is started. The brake fluid pressure is feedback-controlled so that the slip rate of the driving wheels becomes the brake control target slip rate SBT.

At time t3, when the slip rate of the driving wheels becomes less than the target slip rate SBT for brake control, the brake fluid pressure is reduced, and eventually the brake fluid pressure becomes zero, and the slip control by brake control ends.

However, the slip control by engine control is still continued.

The slip rate brake control is performed independently on the left and right sides, for example, based on the slip rates SL and SR of the left and right drive wheels. In addition, the above engine control may be performed using, for example, the slip ratio S of the left and right drive wheels, whichever is larger among the slip ratios SL and SR.
This is done based on E. In addition, the above slip rate SL,
SR is calculated in the control unit UTR according to the following formula based on wheel speed signals from each wheel speed sensor 63 to 66.

VKR-VJ However, VKL: Rotational speed of left driving wheel VKR: Rotational speed of right driving wheel VJ: Average value of rotational speed of left and right driven wheels Note that the slip ratio is not necessarily calculated based on the above formula. It does not have to be, and any value that substantially indicates the slip state of the wheels may be used. For example, a value simply obtained by subtracting the driven wheel speed from the driving wheel speed may also be used.

Regarding rough road correction in traction control, a specific example of rough road correction in traction control will be described in detail with reference to FIG.

In the traction control, first in step 24 it is determined whether the accelerator opening is equal to or greater than a predetermined value.

If the accelerator opening is equal to or greater than a predetermined value (for example, 50%), the process proceeds to step 25, where it is determined whether at least one of the left and right wheels is on a rough road.

If neither road is determined to be rough in step 25, the process proceeds to steps 26 and 27, where normal traction control is performed. That is, the target slip rate STA (5ETSSBT in the above embodiment) is set to the normal target slip rate, and slip control is performed based on the normal target slip rate.

Alternatively, when performing slip control, set the control start threshold VSPA and set the slip rate to that ¥SPA.
(This is set to a value larger than the target slip ratio STA) When controlling the slip ratio to start the slip control so that the slip ratio becomes the target slip ratio STA,
The control start threshold VSPA is set to a normal control start threshold, and slip control is performed based on the VSPA.

On the other hand, if either one of the roads is determined to be rough in step 25, the process proceeds to steps 28 and 29, where rough road correction is performed and traction control is performed. That is, the target slip rate STA of the slip rate engine control is set to a slip rate STA larger than the above-mentioned normal target slip rate.
, or the control start threshold VSPA is set to VSPA+, which is larger than the normal control start threshold, and slip control is performed based on these values.

Note that the rough road correction described above may be performed by increasing both STA and VSPA, or by increasing either one of them.

In addition, STA and VS for engine control and brake control
If there is a PA, both the engine control and brake control may be increased, or either one may be increased. Furthermore, as shown in Fig. 7, even if the target slip rate for brake control is increased by rough road correction (SBT→
SBT, ) Good.

On the other hand, if the accelerator opening degree is smaller than the predetermined value in step 124, the process proceeds to step 30, where it is determined whether or not it is determined that both the left and right wheels are on a rough road.

Then, if none of the roads are bad, step 3
Proceed to steps 1 and 32, perform normal traction control in exactly the same manner as steps 26 and 27 above, and if it is determined that both wheels are on a rough road, proceed to steps 33 and 34, and perform the same procedure as in steps 28 and 29 above. Similarly, rough road correction is performed and traction control is performed.

Rough road correction in ABS control Next, rough road correction in ABS control will be explained.

In the case of slip control, which is ABS control, the only difference is that brake control, which is part of slip control which is traction control, increases brake fluid pressure appropriately, whereas it lowers brake fluid pressure appropriately. The basic device configuration and control are the same as in the case of slip control (traction control) described above (however, the control unit)
The TA stores control programs and various maps for ABS control, and also controls brake fluid pressure for the front wheels in the same way as for the rear wheels. ). Therefore, the specific device and A
A description of the BS control itself will be omitted, and a specific example of rough road correction in the ABS control will be described below with reference to FIG. 9.

In the rough road correction of ABS control, it is determined in step 35 whether or not both wheels are on a rough road. If neither wheel is on a rough road, the process proceeds to steps 36 and 37, and the normal A
BS control is performed. That is, a normal target slip rate is set as the target slip rate S for ABS control, and slip control is performed based on it.

If both wheels are on a rough road, the process proceeds to steps 38 and 39, where rough road correction is performed and slip control is performed. That is, the target slip rate is set to S1, which is smaller than the normal target slip rate S, and slip control is performed based on the smaller target slip rate S1.

(Effects of the Invention) According to the present invention, when determining a rough road, when ABS control is being performed, the reference value of acceleration is made larger than when ABS control is not being performed.

In this case, the reference value is raised to such an extent that it is not affected by acceleration fluctuations caused by ABS control.

This makes it possible to accurately determine rough roads regardless of acceleration fluctuations caused by ABS control.

In addition, when ABS control is being performed, the number of times that fluctuations exceeding the above reference value have occurred for rough road judgment is counted as compared to when ABS control is not being performed. Enlarge.

This makes it less susceptible to acceleration fluctuations caused by ABS control, and makes it possible to more appropriately judge rough roads.

Further, if the road surface on which the vehicle is traveling is determined to be rough, the rough road is corrected so that the target slip rate for traction control is increased. As a result, high power transmission efficiency can be maintained depending on the road surface condition.

Further, if it is determined that the traveling road is a rough road, the target slip rate for ABS control is decreased. This allows effective ABS control to be performed regardless of road surface conditions.

[Brief explanation of drawings]

Fig. 1 is a block diagram schematically showing an embodiment of the present invention, Fig. 2 is an overall system diagram specifically showing an embodiment of the present invention, and Fig. 3 shows rough road correction control in the case of traction control. Flowcharts, FIGS. 4 and 5 are characteristic diagrams showing examples of wheel acceleration changes, FIG. 6 is a flowchart showing rough road judgment, FIG. 7 is a time chart showing aspects of traction control, and FIG. Flowchart showing rough road correction control in traction control FIG. 9 is a flowchart showing bad road correction control in the case of anti-skid control. 100...Slip control means 200...Rough road determination means, A...Vehicle, IRL, IRR...Drive wheel,
IFL, IFR...driven wheel, 2...engine,
3... automatic transmission, 4... propeller shaft,
5... Differential gear device, 6L, 6R.
... Drive shaft, 11 ... Torque converter, 12 ... Multi-speed gear mechanism, 13a, 13b ... Solenoid, UAT ... Control unit for automatic transmission, 43 ...
・Main throttle valve, 44...Actuator, 45...Sub throttle valve, 61...Main throttle valve opening sensor, 62...
...Sub-throttle valve opening sensor, 63...Vehicle speed sensor, 63.21FR~21RR...Brake, 2FR~
22RR...Caliper, 3FR~23RR128,30,33...Piping, 5
... Brake pedal, 26 ... Boost device,
7... Master cylinder, 29... Pump, 2
．． 34... Open/close valve, 35... One-way valve,
6A, 37A...Solenoid on-off valve, 1...Intake passage, 42...Accelerator pedal, 4
~67... Wheel speed sensor, 8... Accelerator opening sensor, 9... Yaw rate sensor, O... Shift sensor, 1... Steering wheel steering angle sensor. 1F4 Figure 5 Figure 6 Figure 7 Figure 11 T+ ”'J' lil

Claims (4)

[Claims] (1) A wheel speed detection means for detecting the speed of the wheels, a wheel acceleration detection means for detecting the acceleration of the wheels based on the wheel speed detection means, and a reference value of the wheel acceleration for determining the rough road. and a rough road determining means that determines that the traveling road is a rough road when a fluctuation exceeding the reference value in the acceleration detected by the wheel acceleration detecting means occurs a predetermined number of times or more within a predetermined period of time. , an anti-skid brake device that performs ABS control, and when the ABS control is performed, the reference value in the rough road determining means is made larger than when the ABS control is not performed; A rough road determining device for a vehicle with ABS, comprising: reference value changing means for changing the reference value according to vehicle speed only when the ABS is not being used. (2) A setting number changing means for increasing the set number of times in the rough road determining means when ABS control is being performed compared to when ABS control is not being performed. The rough road determination device for a vehicle with ABS according to claim 1. (3) a driving wheel speed detecting means for detecting the speed of the driving wheel; a driven wheel speed detecting means for detecting the speed of the driven wheel; and based on the detected values from the driving wheel speed detecting means and the driven wheel speed detecting means. a slip ratio calculation means for calculating a slip ratio of the driving wheels; a traction target slip ratio setting means for setting a target slip ratio for traction control; and traction changing means for increasing the traction target slip rate when the road is determined to be a rough road by the rough road determining means according to claim 1. Features: A rough road determination device for vehicles with ABS. (4) A driving wheel speed detecting means for detecting the speed of the driving wheel, a driven wheel speed detecting means for detecting the speed of the driven wheel, and based on the detected values from the driving wheel speed detecting means and the driven wheel speed detecting means. A slip ratio calculating means for calculating a slip ratio of the drive wheels; an ABS target slip ratio setting means for setting a target slip ratio for ABS control; and controlling a braking force so that the slip ratio converges to the target slip ratio. The vehicle is characterized by comprising: an ABS control means; and an ABS changing means for reducing the ABS target slip ratio when the traveling road is determined to be a rough road by the rough road determining means according to claim 1. Rough road determination device for vehicles with ABS.