JP2526262B2 - Vehicle slip control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a slip control device for an automobile.

(Prior Art) Many of the devices mounted on an automobile determine their control values based on a plurality of input signals. Examples of this kind of equipment include a fuel injection device, an ignition timing control device, an automatic transmission control device, a suspension damping force control device, an anti-brake lock device, a slip (traction) control device, a constant speed traveling device, and the like. There is. And
In recent years, the number of sensors or input signals used has been increasing in order to control these devices (devices) more optimally. As this input signal, the engine speed,
Engine load, vehicle speed, intake air amount, intake air temperature, intake air density, battery voltage, engine cooling water temperature, gear shift position, road slip condition, load, acceleration / deceleration, road slope, wheel speed, steering wheel steering angle, lateral G There are many, including those of the manual type.

As a method for determining a control value for an in-vehicle device using a plurality of such input signals, there is a conventional method disclosed in Japanese Patent Laid-Open No.
There is another one shown in the publication. This shows a case where the basic shift pattern of the automatic transmission is corrected based on a plurality of input signals. To determine the control value for this correction, correction is made for each signal value from each sensor. This is done by finding the term and adding the obtained plurality of correction terms. Further, in order to obtain the control value, in addition to the addition of the correction term, there is a method in which the control value is multiplied by the correction coefficient obtained for each input signal value.

(Problems to be Solved by the Invention) By the way, when the number of input signals that are the basis of control value determination increases, it becomes difficult to obtain an optimum control value by a method such as the above-described addition or multiplication. Explaining this point in detail, as the number of input signals increases, the combination conditions of the signal values increase exponentially. Therefore, creating a correction term (correction coefficient) for each condition while considering all possible combination conditions, for example, if the correction characteristics for one signal value are modified, the overall balance will be lost. Or, finally, an inappropriate control value that cannot be considered at all is obtained.

Further, even if the optimum control values can be obtained for all the combination conditions, the labor required for experiments and the like until such setting is inevitably large. In particular, this optimum control value is often required to match the human (driver) 's sensitivity, so the work of checking and correcting by test running becomes difficult. In addition to this, the characteristic for obtaining the correction term set for each input signal is inevitably complicated and fine, and storing this characteristic becomes a heavy burden on the control system.

In particular, in a vehicle slip control device that adjusts the torque applied to the drive wheels so that the actual slip value for the road surface of the drive wheels becomes a predetermined target slip value, as a parameter for determining the target slip value, for example, vehicle body acceleration, Often, a plurality of parameters indicating the traveling state of the vehicle, such as the steering wheel steering angle and the vehicle speed, are used, and the number of these parameters tends to increase.

The present invention has been made in consideration of the above circumstances, and an object thereof is to appropriately set the target slip value when the target slip value is determined based on a plurality of parameters each indicating the traveling state of the vehicle. An object of the present invention is to provide a slip control device for an automobile that can make a decision.

(Means and Actions for Solving Problems) In order to achieve the above object, the present invention has the following configuration. That is, slip detection means for detecting the slip value of the drive wheels with respect to the road surface, torque adjustment means for adjusting the torque applied to the drive wheels, and running state detection means for detecting a plurality of parameters each indicating the running state of the vehicle, From input signals relating to a plurality of parameters detected by the running state detection means, a target slip value determination means for determining a target slip value based on a fuzzy rule, and a slip value detected by the slip detection means is the target slip value. Torque control means for controlling the torque adjusting means so that the target slip value decided by the deciding means becomes the target slip value.

The target slip value determining means may be specifically configured as follows. That is, a plurality of control zones corresponding to the signal value is preset for each input signal relating to the plurality of parameters, and a basic target slip value storage unit that stores a basic target slip value for each combination of all control zones, A fitness degree determining unit that obtains a fitness degree for each combination by obtaining a fitness degree for each control signal for each input signal value for each combination; and a fitness degree determined by the fitness degree determining unit. From the basic target slip value, the inference target slip value determining means for obtaining the inference target slip value for each combination, and the inference target slip value for each combination and the suitability for each combination, the torque control means And a final target slip value determining means for obtaining a final target slip value to be used. Can. It should be noted that the larger the number of control zones set for one input signal, the more preferable it is to obtain the final target slip value. However, the number of control zones depends on the required control precision and the basic target slip value. It may be determined in consideration of the storage capacity of the storage unit that stores the value.

(Effect of the invention) According to the present invention described in claim 1,
The target slip value is probabilistically determined by a fuzzy rule based on a plurality of parameters, which prevents an inappropriate target slip value from being determined.
The target slip value can always be set to an appropriate value. As a result, it is possible to effectively prevent the slippage of the driving wheels and effectively utilize the grip of the driving wheels to secure sufficient traveling performance such as acceleration. Further, since the target slip value is determined by the fuzzy rule, even if the number of parameters for determining this target slip value is large,
The target slip value can be determined quickly and accurately,
This is preferable for surely preventing excessive slip of the drive wheels.

Further, by adopting the configuration described in claim 2, even if the plurality of input signals have any combination of values, the degree of conformity to the preset control zone is Since verification is performed for each signal value and this verification is performed for all combinations of control zones, it is possible to reliably prevent a situation where an inappropriate final target slip value is selected. Further, the basic target slip value is generally experimentally determined for each combination, but the number of control zones for determining the number of this combination does not need to be so large for one input signal, that is, one parameter. Therefore, the labor required for this experiment work is small. Further, setting a plurality of control zones for one input signal means that the number of control zones, that is, the number of combinations thereof can be reduced as described above, and the basic target slip value is stored in advance. Therefore, the capacity of the storage means will be small.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings.

Overview of Overall Configuration FIG. 1 shows an overview of the overall slip control device. Further, in the embodiment, the torque applied to the drive wheels in the slip control is adjusted by adjusting the torque generated by the engine and adjusting the control force by the brake.

In FIG. 1, an automobile 1 includes four wheels, left and right front wheels 2 and 3 that are drive wheels and left and right rear wheels 4 and 5 that are driven wheels. An engine 6 as a power source is mounted on a front portion of the automobile 1. The torque generated by the engine 6 passes through a clutch 7, a transmission 8, and a differential gear 9, and then passes through left and right drive shafts 10 and 11. And transmitted to the left and right front wheels 2 and 3 as drive wheels. Thus, the vehicle 1 is of the FF type (front engine / front drive).

The engine 6 as a power source has its intake passage 12
Load control, that is, control of generated torque is performed by the throttle valve 13 disposed in the.
More specifically, the engine 6 is a gasoline engine, and the generated torque is changed by the change of the intake air amount, and the intake air amount is adjusted by the throttle valve 13. And the throttle valve 13
The throttle actuator 14 is electromagnetically controlled to be opened and closed. The throttle actuator 14 may be composed of, for example, a DC motor, a step motor, or an appropriate one that is driven by a fluid pressure such as hydraulic pressure and electromagnetically driven and controlled.

Each of the wheels 2 to 5 is provided with a brake 21, 22, 23 or 24, and each of the brakes 21 to 24 is a disc brake. This disc brake is
As is known, it comprises a disc 25 which rotates with the wheels and a caliper 26. The caliper 26 holds a brake pad and includes a wheel cylinder, and a braking force is generated by pressing the brake pad against the disc 25 with a force according to the magnitude of the brake fluid pressure supplied to the wheel cylinder. .

The master cylinder 27 as a brake fluid pressure generation source has two
It is of a tandem type having two discharge ports 27a and 27b.
The brake pipe 28 extending from the discharge port 27a is branched into two branch pipes 28a and 28b on the way, and the branch pipe 28a is connected to (the wheel cylinder of) the brake 22 for the right front wheel.
b is connected to the left rear wheel brake 23. A brake pipe 29 extending from the discharge port 27b branches into two branch pipes 29a and 29b on the way, the branch pipe 29a is connected to the left front wheel brake 21, and the branch pipe 29b is connected to the right rear wheel brake 24. It is connected to the. In this way, the brake piping system is of the so-called two-system X type. The branch pipes 28a, 29a for the front wheel brakes 21, 22 serving as drive wheels are provided with electromagnetic hydraulic control valves 30 or 31 as braking force adjusting means.
Is connected. Of course, the brake fluid pressure generated in the master cylinder 27 depends on the amount of depression (depression force) of the brake pedal 32 by the driver D.

Brake Hydraulic Pressure Control Circuit As shown in FIG. 2, the hydraulic pressure control valves 30 and 31 are
Each has a cylinder 41 and a fixer 42 slidably fitted in the cylinder 41. The interior of the cylinder 41 is divided into a variable volume chamber 43 and a control chamber 44 by the piston 42. The variable volume chamber 43 serves as a passage system for the brake fluid pressure from the master cylinder 27 to the brake 21 (22). Therefore, by adjusting the displacement position of the piston 42, the volume of the variable volume chamber 43 can be changed to generate brake fluid pressure for the brake 21 (22), and increase or decrease or maintain the generated brake fluid pressure. Will be able to do it.

The fixer 42 has a variable volume chamber with a return spring 45.
It is always urged to increase the volume of 43. A check valve 46 is integrated with the piston 42. The check valve 46 closes the inlet side of the variable volume chamber 43 when the piston 42 is displaced in the direction of reducing the volume of the variable volume chamber 43. As a result, the brake fluid pressure generated in the variable volume chamber 43 is reduced by the brake 21 (2
2) It acts only on the side and does not act on the brakes 23, 24 of the rear wheels 4, 5 as driven wheels.

The displacement position of the piston 42 is adjusted by adjusting the control hydraulic pressure for the control chamber 44. Explaining this point in detail, the supply pipe 48 extending from the reservoir 47 is branched into two in the middle, and one branch pipe 48R is connected to the control chamber 44 of the valve 30.
And the other branch pipe 48L is connected to the control room 4 of the valve 31.
Connected to 4. A pump 49 and a relief valve 50 are connected to the supply pipe 48, and a supply valve SV3 (SV2) which is an electromagnetic on-off valve is connected to a branch pipe 48L (48R) of the supply pipe 48. Each control room 44 has a discharge pipe 51R or 51L.
A discharge valve SV4 (SV1), which is an electromagnetic on-off valve, is connected to the reservoir 47 via the discharge pipe 51L (51R).

At the time of braking using the hydraulic pressure control valve 30 (31) (during slip control), the check valve 46 basically prevents the brake pedal 32 from operating. However, the hydraulic pressure control valve 30
When the brake fluid pressure generated in (31) is small (for example, during pressure reduction), the brake is operated by operating the brake pedal 32. Of course, when the brake fluid pressure for slip control is not generated by the fluid pressure control valve 30 (31), the master cylinder 27 and the brake 21 (22) are in communication with each other. As a result, a normal braking action is performed.

The valves SV1 to SV4 are controlled to open and close by a brake control unit UB, which will be described later. Brake 2
Table 1 below summarizes the state of the brake fluid pressure to the valves 1 and 22 and the operation relationship between the valves SV1 to SV4.

Control Unit Configuration Overview In FIG. 1, U is a control unit,
This is roughly divided into a brake control unit UB, a throttle control unit UT, and a slip control control unit Us. The control unit UB controls the opening and closing of each of the valves SV1 to SV4 based on the command signal from the control unit US as described above. Further, the throttle control unit UT controls the drive of the throttle actuator 14 based on the command signal from the control unit Us.

The slip control unit U S is composed of a digital computer, more specifically, a microcomputer. Signals from the sensors (or switches) 61 to 68 are input to the control unit US. The sensor 61 is connected to the throttle valve 13
This is for detecting the opening degree. The sensor 62 detects whether or not the clutch 7 is engaged. Sensor 63
Is for detecting the gear stage of the transmission 8. Sensor 64,
Reference numeral 65 indicates the number of rotations of the left and right front wheels 2 and 3 as drive wheels. The sensor 66 detects the rotational speed of the rear left wheel 4 as a driven wheel, that is, the vehicle speed. The sensor 67 detects the operation amount of the accelerator 69, that is, the accelerator opening degree. The sensor 68 detects an operation amount of the steering wheel 70, that is, a steering angle. The sensors 64, 65, and 66 are each configured using, for example, a pickup, and the sensors 61, 6
3, 67, 68 are configured using, for example, a potentiometer, and the sensor 62 is configured, for example, by a switch that operates ON and OFF.

The control unit Us is basically a CPU, RO
Equipped with M, RAM, CLOCK, and other input / output interfaces, and A / D according to input and output signals.
It also has a D or D / A converter, but since these points are the same as those in the case of using a microcomputer, detailed description thereof will be omitted. The maps and the like in the following description are stored in the ROM of the control unit Us.

Next, the control contents of the control unit U will be sequentially described. The slip ratio S used in the following description is
It is defined by the following equation (1).

WD: Number of rotations of drive wheels (2, 3) WL: Number of rotations of driven wheel (4) (vehicle speed) Throttle control The control unit UT feeds back the throttle valve 13 (throttle actuator 14) so that the target throttle opening is achieved. It is controlled.
When the slip control is not performed during the throttle control, the operation of the accelerator 69 operated by the driver D is 1:
Control to reach the target throttle opening corresponding to 1,
An example of the correspondence between the accelerator opening and the throttle opening at this time is shown in FIG. Further, during slip control, the control unit UT does not follow the characteristics shown in FIG. 12, but performs throttle control such that the target throttle opening Tn calculated by the control unit Us is reached.

Throttle valve 1 with control unit UT
In the embodiment, the feedback control 3 is performed by PI-PD control in order to compensate the variation in the response speed of the engine 6. That is, during slip control of the drive wheels, PI-PD control is performed on the opening of the throttle valve 13 so that the current slip rate matches the target slip rate. More specifically, the target throttle opening Tn during slip control
Is calculated by the following equation (2).

WL: Revolution of driven wheel (4) WD: Revolution of drive wheel (2, 3) KP: Proportional constant KI: Integral constant FP: Proportional constant FD: Differential constant SET: Target slip ratio (for throttle control) As shown in (2), the throttle opening Tn is feedback-controlled on the rotation speed of the drive wheels so as to reach a predetermined target slip ratio SET. In other words, as is apparent from the equation (1), the throttle opening is calculated by the following equation (3) when the target drive wheel rotation speed WET is Is controlled so that

PI-PD control using the above-mentioned control unit UT is shown in FIG. 3 as a block diagram, and “S ′” shown in FIG. 3 is an “operator”. The suffixes “n” and “n−1” indicate the value of each signal at the current time and at the time of the previous sampling.

Brake control During slip control, the control unit U
The rotation (slip) of the left and right drive wheels 2, 3 using B
Feedback control is performed independently on the left and right sides so that a predetermined target slip rate SBT is achieved. In other words, in the brake control, feedback control is performed so that the drive wheel rotation speed WBT is set by the following equation (4).

The target slip rate SBT of this brake is set to be larger than the target slip rate SET of the engine in this embodiment, as will be described later. In other words, in the slip control of the present embodiment, the engine output is increased / decreased to the predetermined SET (WET), and the torque is increased / decreased by the brake so as to increase the SBT (WBT) larger than the predetermined SET (WET). It is used less frequently. Then, in this embodiment, the feedback control satisfying the expression (4) is performed by the I-PD control having excellent stability. More specifically, the brake operation amount (valves 30, 31
The operation amount Bn of the piston 44 in is calculated by the following equation (5).

KI: Integral coefficient KD: Proportional coefficient FD: Differential coefficient When the above Bn is greater than 0 (when "positive"), the brake fluid pressure is reduced, and when it is 0 or less, the pressure is increased. This increase / decrease in brake fluid pressure is controlled by valves SV1-S
This is done by opening and closing V4. Further, the increase / decrease speed of the brake fluid pressure is adjusted by adjusting (duty control) the ratio (duty ratio) of the opening / closing times of the valves SV1 to SV4. The duty control is proportional to the absolute value. Therefore, the absolute value of Bn is proportional to the change speed of the brake fluid pressure, and conversely, the duty ratio for determining the increase / decrease speed also indicates Bn.

The I-PD control by the control unit UB described above is shown as a block diagram in FIG.
“S ′” shown in the figure is an “operator”.

Determination of the target slip rate SET for the engine Now, the point of determining the target slip rate SET for the engine based on a plurality of input signals, which is an essential part of the present invention, will be described. In the present embodiment, three types of vehicle body acceleration G, steering wheel steering angle D, and vehicle speed V are used as a plurality of input signals for determining the target slip rate SET.

First, referring to FIGS. 18 to 20, setting of the control zone,
The setting of the matching degree will be described. Two control zones, "large" and "small", are set for each of the input signals G, D, and V, respectively. That is, when the signal value G (× gravity acceleration) of the vehicle body acceleration is larger than “0.05”, the control zone is “large” (the right side of the broken line in FIG. 18), and the signal value G is larger than “0.15”. When the control zone is small, the control zone is “small” (the left side of the solid line in FIG. 18). Similarly, for the steering wheel angle, the signal value D (deg) is “3”.
When the control zone is larger than “0”, it is “large” (19th
When the signal value D is smaller than “70”, the control zone is “small” (the left side from the solid line in FIG. 19). Regarding the vehicle speed, the signal value V (km / h) is "10"
The control zone when it is larger is "large" (the part on the right side of the broken line in Fig. 20), and the control zone is "small" when the signal value V is smaller than "60" (on the left side of the solid line in Fig. 20). part).

18 to 20 are maps in which the degrees of conformity KA, KB or KC are set for both the "large" and "small" control zones. To explain this point, both the “large” and “small” control zones have areas overlapping each other. Then, the overlapping portions, that is, 0.05 ≦ G ≦ 0.15, 30 ≦ D ≦ 70, and 10 ≦ V ≦ 60 are “large”.
Is a boundary zone between the control zones of “large” and “small”, and this portion has a degree of conformity of “0” to “1.0” (0% to 100%) for both the “large” and “small” control zones ). Therefore, for example, if the signal value G is 0.05,
Assuming a value between 0.15 and g1, for example, the fitness for the “small” control zone at that time is β1 based on the solid line in FIG. 18, and the fitness for the “large” control zone is It becomes β2 in light of the broken line in FIG. Of course, the signal value G is
When it is less than 0.05, the degree of conformity to the "small" control zone is 1.0 (100%), and conversely, the degree of conformity to the "large" control zone is 0 (0%). When the signal value G is 0.15
The degree of conformity to the "large" control zone when larger is
1.0 (100%), and conversely, the degree of conformity to the “small” control zone is 0 (0%). The above is the signal value D,
The same applies to the degree of conformity of the signal value V.

There are a total of 6 control zones due to the setting of the two control zones of “large” and “small” for the three input signals G, D, and V described above. There are a total of 8 combinations of large and small V], and these combinations are collectively shown in Table 2 below.

In this second table, the combinations of control zones are displayed as rules R1 to R8. For example, rule R1 is a combination of [G, D, V] control zones [small, small,
Small] and rule R5 is [Large, Small, Small].

Experimentally, that is, the basic target slip value Ti (i = 1, 2, ...
8) has been decided. That is, focusing on the rule R1, a test is performed in a state where the signal values G, D, and V are all in the “small” control zone, and 0.15 is obtained as the optimum basic target value T1. Also, focusing on the rule R7, an optimum test is performed when both the signal values G and D are in the "large" control zone and the signal value V is in the "small" control zone. As a basic target value T7, 0.05 is obtained. Of course, when performing the test for obtaining the basic target value, the input signal value with which the degree of conformity to the “large” or “small” control zone is 1.0 is adopted (in rule R1). As the signal value G when the basic target value T1 = 0.15 is determined, a value smaller than 0.05 is used so that the goodness of fit for the "small" control zone is 1.0).

The determination of the final target slip value according to the above-mentioned Table 2 and FIGS. 18 to 20 is performed as follows.

First, for rule R1, the degree of conformance KA, KB or KC for each signal value G, D, V with respect to the control zone is obtained. That is, the conformity KA for the signal value G is obtained with reference to FIG. 18, and the conformity in this case is determined by the rule R1.
Since the control zone is set as “small” for the signal value G, the degree of conformity to the “small” control zone is determined. Similarly, since the control zone is set as "small" for the signal value D in the rule R1, the fitness KB for the "small" control zone is determined with reference to FIG. Similarly, in the rule R1, the fitness KC for the "small" control zone for the signal value V is obtained with reference to FIG.

The signal value G for the rule R1 determined above,
The respective KA, KB, and KC for D and V are multiplied by each other, and the fitness W1 in the entire rule R1 is obtained (W1 = KA.times.KB.times.KC).

Further, the inference target value M1 for the rule R1 is obtained for W1 for the rule R1 obtained in (M1
= W1 × T1).

The above-mentioned items (1) to (8) are sequentially performed from the rules R2 to R8, and the fitness values W1 to W8 and the inferred target slip values M1 to M8 are obtained for each of the rules R1 to R8 (see also Table 2). .

By applying W1 to W8 and M1 to M8 obtained above to, for example, the following equation (6), the final control value SET is obtained. That is, by dividing the value obtained by adding each inference control value M1 ... M8 for all combinations (rules R1 to R8) by the value obtained by adding the goodness of fit W1 ... W8 for all combinations. , SET as the final control value is calculated.

For each of the rules R1 to R8, first, the signal value G,
The suitability KA, KB, and KC may be obtained for D and V, and then the suitability W1 to W8 and the inference target values M1 to M8 may be obtained. In this case, the suitability for all the rules R1 to R8 is once obtained. Since the degrees KA, KB and KC (there are a total of 24 values) must be stored, it is preferable to carry out the above-mentioned method from the viewpoint of reducing the storage capacity.

Determination of the target slip ratio SET for the engine (flowchart)
Description will be made based on the flowchart shown in FIG. In addition,
In the following description, P indicates a step.

After each signal value G, D, and V is measured in P81 in FIG. 21, in P82, the fitness Wi, Mi (i = 1 to 1)
8) is initialized to “0”.

Next, in P83 to P90 described later, the fitness W1 to W8 and the inference target values M1 to M8 for the rules R1 to R8 are calculated.
Then, finally, in P91, the target slip ratio SET for the engine as the final target value is calculated based on the equation (6).

The details in P83 are performed as shown in FIG.
First, it is determined whether or not each of the signal values G, D, and V is in the “small” control zone (P101 to P103), and each of the signal values G, D, and V is in the “small” control zone. (When YES in each of P101 to P103), the matching degrees KA, KB, and KC are read with reference to the maps shown in FIGS. 18 to 20 (P104 to P106). Next, after W1 is calculated in P107, M1 is calculated in P108. On the other hand, P101, P1
When NO is determined in either 02 or P103, the process directly proceeds to the next step P84 in FIG. In this case, P82
W1 and W1 are both set to "0" by the initialization at.

The details of P84 in FIG. 20 are as shown in FIG. In FIG. 23, since it relates to the rule R2, the discrimination in P201 to P203 indicates that [G, D, V] is [Small,
Small and large] in FIG.
Since it is substantially different from P103, further detailed description is omitted. Also, for details on P85 to P90 in Fig. 21, see
Since it is already clear from the description with reference to FIGS. 21 and 22, the description of this point is also omitted.

Here, an example of determining the rate SET for all engine targets as described above will be described using specific numerical values. That is, consider the case of [0.1, 30, 60] as an example of [G, D, V]. At this time, each rule R
For each of 1 to R8, Wi (KA x KB x KC), Mi (Ti x
Wi) is as follows.

Rule R1 W1 = 0 (0.5 × 1.0 × 0) M1 = 0 (0.15 × 0) Rule R2 W2 = 0.5 (0.5 × 1.0 × 1.0) M2 = 0.05 (0.10 × 0.5) Rule R3 W3 = 0 (0.5 × 0 ×) 0) M3 = 0 (0.02 × 0) Rule R4 W4 = 0 (0.5 × 0 × 1.0) M4 = 0 (0.01 × 0) Rule R5 W5 = 0 (0.5 × 1.0 × 0) M5 = 0 (0.20 × 0) Rule R6 W6 = 0.5 (0.5 × 1.0 × 1.0) M6 = 0.075 (0.15 × 0.5) Rule R7 W7 = 0 (0.5 × 0 × 0) M7 = 0 (0.05 × 0) Rule R8 W8 = 0 (0.5 × 0 ×) 1.0) M8 = 0 (0.02 × 0) W1 to W8 and M1 to M8 obtained as described above are expressed by equation (6).
By applying this, SFT = 0.125 is obtained as the final target value. This "0.125" is calculated by inference
It has been selected as an intermediate value between 2 and R6.

Determination of target slip rate SBT for brake The target slip rate SBT for brake is also determined based on three signals of acceleration G, steering wheel steering angle D, and vehicle speed V, like the engine target slip rate SFT. In determining SBT, the suitability of each signal G, D, V to the control zone is determined with reference to FIGS. 18 to 20. However,
The basic value Ti is the basic value for SET as shown in Table 3 below.
It is set differently from Ti.

The method of determining SBT is performed in the same manner as the above-described determination of SET, so that [G, D, V] is [0.1, 3
[0,60] is shown as an example, and the duplicate description is omitted. Of course, the flow chart for determining this SBT is also shown in FIGS. 21 to 23, though not shown (however, “SE” in P91 of FIG.
"T calculation" becomes "SBT" calculation).

Rule R1 W1 = 0 (0.5 × 1.0 × 0) M1 = 0 (0.20 × 0) Rule R2 W2 = 0.5 (0.5 × 1.0 × 1.0) M2 = 0.075 (0. (15 × 0.5) Rule R3 W3 = 0 (0.5 × 0 × 0) M3 = 0 (0.03 × 0) Rule R4 W4 = 0 (0.5 × 0 × 1.0) M4 = 0 (0.015 × 0) Rule R5 W5 = 0 (0.5 × 1.0 × 0) M5 = 0 (0.30 × 0) Rule R6 W6 = 0.5 (0.5 × 1.0 × 1.0) M6 = 0.1 (0.2 × 0.5) Rule R7 W7 = 0 (0.5 × 0 × 0) M7 = 0 (0.08 × 0) Rule R8 W8 = 0 (0.5 × 0 × 1.0) M8 = 0 (0.03 × 0) By applying W1 to W8 and M1 to M8 obtained as described above to the following equation (7), SBT = 0.175 is obtained as the final target value.

Overall Outline of Slip Control An overall outline of slip control by the control unit U will be described with reference to FIG. In addition,
In the embodiment, when the slip of the drive wheels is large, the slip control is performed by both reducing the torque generated by the engine and applying the braking force by the brake, while when the slip of the drive wheels is small, the slip control is performed only by adjusting the torque generated by the engine. Is supposed to do. For this reason, the target slip ratio SET for the engine is set smaller than the target slip ratio SBT for the brake, and the slip ratio SBC for stopping the brake control for completely interrupting the slip control by the brake is slightly smaller than the SET. It is set as a large value. The meanings of the symbols and numerical values shown in FIG. 5 are as follows.

S / C: Slip control area E / G: Engine slip control B / R: Brake slip control F / B: Feedback control O / R: Open loop control R / Y: Recovery control B / A: Backup control A / S: Damping control S = 0.2: Slip rate at the start of slip control (SS) S = 0.17: Target slip rate by brake (SBT) S = 0.09: Slip rate at stop of slip control by brake (SBC) S = 0.06: Target slip rate (SET) by engine S = 0.01 to 0.02: Slip rate in the range where buffer control is performed S = 0.01 or less: Slip rate in the range where backup control is performed Note that the above values are actually ice-burn spike tires. It is shown based on the data obtained by driving by. Then, S = 0.01 and 0.02 for performing the buffer control A / S, and the slip ratio S = 0.09 at the slip control stop point by the brake.
Are unchanged in the embodiments. On the other hand, the target slip rate SBT by the brake, the target slip rate SET by the engine, and the slip rate SS at the start of the slip control are changed depending on the road surface condition and the like, and in FIG. , "0.06" or "0.2" are shown. The slip rate S = 0.2 at the start of slip control uses the slip rate at the time of maximum grip force generation obtained when using a spike tire (see the solid line in FIG. 13). In this way, the slip ratio at the start of slip control is increased to 0.2 in order to obtain the actual slip ratio when this maximum grip force is obtained. The target slip ratios SET and SBT by the engine and the brake are corrected according to the slip ratio. The solid line in FIG. 13 shows how the magnitude of the grip force and the lateral force (shown as a friction coefficient with respect to the road surface) in the case of a spike tire changes in relation to the slip rate. Further, the broken line in FIG. 13 shows the relationship between the grip force and the lateral force in the case of a normal tire.

Based on the above, FIG. 5 will be described over time.

Since the slip ratio S from t _{0 to} t ₁ does not exceed S = 0.2 which is the slip control start condition, slip control is not performed. That is, when the slip of the driving wheels is small, the acceleration performance can be improved by not performing the slip control (traveling using a large grip force). Of course, at this time,
The characteristic of the throttle opening with respect to the accelerator opening is uniformly determined as shown in FIG.

t ₁ with ~t ₂ slip control is started, the slip rate is when the above slip control stop point by the brake (S = 0.09). At this time, since the slip ratio is relatively large, slip control is performed by reducing the torque generated by the engine and braking by the brake. Also, since the target slip rate of the brake (S = 0.17) is larger than the target slip rate of the engine (S = 0.06), the brake is pressed during a large slip (S> 0.17), but during a small slip. At (S <0.17), the brake is not pressurized, and the slip is controlled by the control of only the engine.

between t ₂ ~t ₄ (Recovery Control) slip convergence (S <0.2) and a predetermined time after (e.g. 170 msec), the throttle valve 13 is held at a predetermined opening (open loop control). At this time, S = 0/2
The maximum acceleration GMAX at the time (t ₂ ) is obtained, and this GM
The maximum μ on the road surface (maximum driving force of the driving wheels) is estimated from AX. Then, the throttle valve 13 is held for a predetermined time as described above so as to generate the maximum grip force of the drive wheel. This control is performed in order to prevent the body acceleration G from dropping immediately after the convergence of the slip because the response is not enough in the feedback control because the convergence of the slip occurs rapidly. Therefore, when the convergence of the slip is predicted (lower than S = 0.2), the predetermined torque is secured in advance as described above, and the acceleration is improved.

The optimum throttle opening TV ₀ for realizing the torque applied to the drive wheels that can generate the maximum grip force is
Although it is theoretically obtained from the torque curve and the gear ratio of the engine 6, in the embodiment, it is determined based on, for example, a map as shown in FIG. This map is created by an experimental method, and when GMAX is 0.15 or less and 0.4 or more, it is set to a predetermined constant value in consideration of the measurement error of GMAX. The map shown in FIG. 12 is premised at a certain shift speed (for example, the first speed), and the optimum throttle opening TV ₀ is corrected at the other shift speeds.

t _{4 to} t ₇ (backup control, buffer control) To cope with the slip rate S abnormally decreasing,
Backup control is performed (oven loop control).
That is, when S <0.01, the feedback control is stopped and the throttle valve 13 is opened stepwise. When the slip ratio is between 0.01 and 0.02, in order to smoothly transition to the next feedback control, buffer control is performed (t ₄ ~t ₅ and t ₆ ~t _7). This backup control is performed when the feedback control and the recovery control cannot cope. Of course, the backup control has a sufficiently high response speed than the feedback control.

In this embodiment, the rate of increase of the throttle opening in the backup control is 0.5% with respect to the previous throttle opening every 14 msec of the throttle opening sampling time.
It is assumed to be added by the opening.

Further, in the above buffer control, as shown in FIG. 16, a throttle opening T ₂ obtained by the feedback control calculation, and a throttle opening T ₁ obtained by the backup control operation, the current slip ratio S ₀ It is set as the throttle opening T ₀ obtained by proportional distribution.

By controlling the up t ₇ ~t ₈ t _7, a smooth transition to only by the slip control engine.

After t ₈ Since the accelerator 69 is completely closed by the driver D, the slip control is stopped. At this time, even if the opening degree of the slot valve 13 is left to the will of the driver D, there is no risk of re-slip because the torque is sufficiently reduced. Note that the slip control is stopped in the embodiment in addition to fully closing the accelerator,
It is also performed when the target throttle opening degree by the slip control becomes smaller than the throttle opening degree determined by FIG. 12 corresponding to the accelerator opening degree operated by the driver.

Details of Slip Control (Flowchart) Next, the details of the slip control will be described with reference to the flowcharts of FIGS. 6 to 11. In the embodiment, in the stack in which the vehicle 1 is stuck in muddy or the like, A stack control for getting out of the mud or the like is also performed by using the brake control. In the following description, P indicates a step.

FIG. 6 (Main) After the system has been initialized in P1, it is determined in P2 whether or not the vehicle is currently in a stack state (a state in which it cannot be stuck in a muddy area or the like). This determination is made by checking whether or not a stack flag described later is set. If the determination in P2 is NO, it is determined in P3 whether the accelerator 69 is fully closed. If NO is determined in P3, it is determined in P4 whether the current throttle opening is larger than the accelerator opening. When NO is determined in P4, it is determined in P5 whether or not slip control is currently being performed. This determination is made by checking whether or not the slip control flag is set. this
When NO is determined in P5, it is determined in P6 whether or not slip for performing slip control has occurred. This determination is made by checking whether a slip flag has been set for the left and right front wheels 2 and 3 described below. When NO is determined in P6, the process shifts to P7 and the slip control is stopped (normal traveling).

When YES is determined in P6, the process shifts to P8, and the slip control flag is set. Continue to P9 and
At P10, the target slip rate SET for the engine and the target slip rate SBT for the brake described above are determined based on the G, D, and V input signals (FIGS. 21 to 23). Thereafter, as described later, brake control at P11 and engine control at P12 are performed for slip control.

If YES is determined in P5, the above-mentioned P9
When it is determined to be YES in P4, the slip control is not needed, and the process proceeds to P14. At P14, the slip control flag is reset. Next, the engine control is stopped at P15, and the brake control is performed at P16.
Note that the brake control in P16 is performed as a countermeasure during the stack.

If YES is determined in P3, the brake is released in P13, and then the processes from P14 are performed.

When YES is determined in P2, the processing after P15 is performed.

The flowcharts of FIGS. 7 and 8 are interrupted, for example, every 14 msec with respect to the main flowchart of FIG.

First, in P21, each signal from each of the sensors 61 to 68 is input for data processing. Next, after the process of slip detection described later is performed in P22, the throttle control is performed in P23.

The throttle control in P23 is performed according to the flowchart shown in FIG. First, in P24, it is determined whether or not the slip control flag is set, that is, whether or not slip control is currently being performed. this
When YES in P24, the control of the throttle valve 13 is selected for slip control, that is, control that realizes a predetermined target slip ratio SET without following the characteristics shown in FIG. When NO is determined in P24, the opening / closing control of the throttle valve 13 is performed in P26.
It is selected as subject to the will of the driver D (according to the characteristics shown in FIG. 12). After P25 and P26, control for achieving the target throttle opening degree is performed in P27 (control according to P68, P70, P71 described later or the 12th control).
Control according to the characteristics of the figure).

FIG. 9 (slip detection process) The flowchart of FIG. 9 corresponds to P22 of FIG. This flowchart is for detecting whether or not a slip which is a target of the slip control has occurred and whether or not the vehicle is stuck.

First, at P31, it is determined whether or not the clutch 7 is completely connected. If YES is determined in this P31,
The stack flag is reset in P32 as if it was not in the stack. Next, in P33, it is determined whether or not the current vehicle speed is low, that is, for example, smaller than 6.3 km / h.

When NO is determined in P33, the correction value α for slip determination is calculated in P34 according to the steering wheel deviation angle (see FIG. 14). Thereafter, in P35, it is determined whether or not the slip ratio of the left front wheel 2 as the left driving wheel is larger than a value (0.2 + α) obtained by adding α in P34 to the predetermined reference value 0.2. If the determination in P35 is YES, it is determined that the left front wheel 2 is in the slip state, and the slip flag is set. Conversely, when it is determined to be NO in P35, the left front wheel 3
The slip flag of is reset. The above correction value α
Is set in consideration of the difference in rotation between the inner and outer wheels during turning (in particular, the difference in rotation between the drive wheel and the driven wheel).

After P36 or P37, in P38, P39, and P40, the slip flag for the right front wheel 3 is set or reset in the same manner as in P35, P36, and P37.

When YES is determined in P33, it means that the vehicle is running at low speed, and the error in the calculation of the slip ratio based on the equation (1) becomes large.
The detection is made based only on the rotation speed of the drive wheels.
That is, in P41, the rotation speed of the left front wheel 2 is 10 kV.
It is determined whether or not it is higher than the number of revolutions corresponding to m / h. If YES is determined in P41, the left front wheel 2
Is set. Conversely, if NO is determined in P41, the slip flag of the left front wheel 2 is reset in P43.

After P42 and P43, in P44, P45 and P46, the right front wheel 3
The slip flag for is set or reset in the same manner as in the case of P41 to P43.

When it is determined to be NO in P31, it is considered that the vehicle may be in the stack (during the stack, the driver D tries to escape from the mud or the like while using the half clutch). In this case, shift to P51,
It is determined whether or not the rotational speed difference between the left and right wheels 2 and 3 as driving wheels is small (for example, the rotational speed difference is converted into a vehicle speed of 2 km / h).
It is determined whether or not the following). When NO is determined in p51, it is determined in P52 whether or not the stack control is currently being performed. When it is determined to be NO in P52, it is determined in P53 whether or not the rotation speed of the right front wheel 3 is higher than the rotation speed of the left front wheel 2. When YES is determined in P53, it is determined whether or not the rotation speed of the right front wheel 3 is larger than 1.5 times the rotation speed of the left front wheel 2. When YES is determined in this P54, the stack flag is set in P56. Conversely, P
If NO is determined in 54, it means that it is not in the stack,
The processing after P32 described above is performed.

When it is determined to be NO in P53, it is determined in P55 whether the rotational speed of the left front wheel 2 is greater than 1.5 times the rotational speed of the right front wheel 3. If YES in P55, the process proceeds to P56, and if NO, the process proceeds to P32.

After P56, it is determined in P57 whether the vehicle speed is higher than 6.3 km / h. If YES in this P57,
The target rotation speeds of the front wheels 2 and 3 are determined by the following
It is set to be 1.25 times (equivalent to a slip rate of 0.2). When NO in P57, in P59, the front wheel 2,
The target speed of 3 is set uniformly to 10 km / h.

If YES in P51, the brake is slowly released in P60. If YES in P52, P53, P54,
The process directly shifts to P56 without performing the process of P55.

FIG. 10 (Engine control) The flowchart shown in FIG. 10 corresponds to P12 in FIG.

In P61, whether the transition slip to a converged state (whether the time that has passed through t ₂ time points of FIG. 5) is determined. When NO in P61, it is determined in P62 whether the slip ratio S of the left front wheel 2 is larger than 0.2. At P62
If NO, it is determined in P63 whether the slip ratio S of the right front wheel 3 is greater than 0.2. If NO in P63, it is determined in P64 whether only one of the left and right front wheels 2, 3 is under brake control, that is, whether the vehicle is traveling on a split road. If YES in P64, in P65,
The current slip ratio is calculated according to the drive wheel having the lower slip ratio among the left and right front wheels 2 and 3 (select low). Conversely, when the answer is NO in P64, the current slip ratio is calculated according to the drive wheel having the larger slip ratio among the left and right front wheels 2 and 3 (select high). Even if NO in P62 and P63, the process shifts to P66.

The select high in P65 allows the use of the brake to be further avoided by calculating the current slip ratio in order to suppress the slip of the drive wheel that is more likely to slip. On the other hand, the select low in P65 described above suppresses slippage of the drive wheel that is more slippery by the brake when traveling on a split road where the road surface on which the left and right drive wheels are in contact has different friction coefficients It will be possible to drive while making use of the grip of the drive wheels on the difficult side.
In the case of this select low, in order to avoid overuse of the brake, it is advisable to provide a backup means for limiting the select time, for example, or for stopping the select low when the brake is overheated.

After P65 and P66, at P67, the current slip ratio S
It is determined whether it is greater than 0.02. If YES in P67, in P68, the throttle valve 13 is feedback-controlled for slip control.

If NO in P67, the current slip ratio S is
It is determined whether it is greater than 0.01. If YES in P69, the above-described buffer control is performed in P70. If NO in P69, the backup control described above is performed in P71.

On the other hand, if YES in P61, the flow shifts to P72, where it is determined whether or not a predetermined time (the time for performing recovery control, 170 msec in the embodiment as described above) has elapsed after slip convergence. When the answer is NO in P72, the processing after P73 is performed to perform the recovery control. That is, first, at P73, the maximum acceleration GMAX is measured of the automobile 1 (FIG. 5 t ₂ time).
Then, in P74, the optimum throttle opening Tv ₀ as this GMAX is obtained is set (see FIG. 15). Further, at P75, according to the current gear position of the transmission 8, P
The optimal throttle opening Tv ₀ at 74 is corrected. That is, since the applied torque to the drive wheels also differs depending on the shift speed, the optimal throttle opening Tv ₀ for a certain reference shift speed is set in P74, and the difference in the shift speed is corrected in P75. It is. This is P73, P73
Estimate the friction coefficient of the road surface from GMAX in step 1 and change both the target slip ratios SET and SBT for slip control by the engine (throttle) and brake. How to change the target slip rates SET and SBT will be described later.

If YES in P72, it means that the recovery control is to be ended, and the above-described processing from P62 is performed.

FIG. 11 (Brake control) The flowchart shown in FIG. 11 corresponds to P11 and P16 in FIG.

First, in P81, it is determined whether or not the stack is currently being stacked. When NO in P81, in P82, the limit value (maximum value) of the brake response speed Bn (corresponding to the duty ratio for opening / closing control of SV1 to SV4) is set to a function corresponding to the vehicle speed (the larger the vehicle speed, the larger the value) Set as Conversely, P81
If the answer is YES in P83, the limit value BLM is
Set as a constant value smaller than 82. Note that the processing in P82 and P83 takes into account that, when Bn is calculated as in the above equation (5), the rate of increase and decrease of the brake fluid pressure is too fast, which may cause vibration or the like. Done. In addition, in P83, since it is not particularly preferable that the braking force applied to the drive wheels suddenly changes due to escape from the stack, the limit value is set to a small constant value.

After P82 or P83, the slip rate S at P84
Is greater than 0.09, which is the stop point of the brake control. If YES in P84, the operating speed Bn of the right front wheel brake 22 is calculated in P85 (corresponding to Bn in 1-PD control in FIG. 4). Thereafter, in P86, it is determined whether or not Bn is greater than “0”. This determination is a determination as to whether or not the pressure reducing direction of the brake is positive and the pressure increasing direction is negative.
If YES in P86, it is determined in P87 whether Bn> BLM. If YES in P87, set Bn to the limit value BLM
After setting to, the pressure of the right brake 22 is reduced at P89. When NO in P87, the pressure is reduced in P89 with the value of Bn set in P85.

If NO in P86, Bn is “negative” or “0”, so after Pn is converted to an absolute value in P90, the processes in P91 to P93 are performed. These P91 to P93 are when the pressure of the right brake 22 is increased, and correspond to the processes of P87, P88, and P89. On the other hand, if NO in P84, it means that the brake control is to be stopped, so the brake is released in P95.

After P89, P93, and P95, move to P94 and left brake 21
As for the right brake 22, pressure increase or pressure decrease is performed (process corresponding to P84 to P93 and P95).

When the difference between the actual rotation speed of the drive wheel and the target rotation speed (actual slip ratio and target slip ratio) is large between P85 and P86, for example, the integration constant KI in the above equation (5) is calculated. Performing the correction to reduce the value is preferable in preventing acceleration deterioration and engine stall due to excessive braking.

Change of target slip rates SET and SBT (P76) The target slip rates SET and SBT of the engine and the brake changed in P76 are based on the maximum acceleration GMAX measured in P73, for example, as shown in FIG. Be changed. As is apparent from FIG. 17, in principle, as the maximum acceleration GMAX increases, the target slip rates SET and SBT increase.
Is designed to be large. And the target slip rate S
Limit values are set for ET and SBT respectively.

Here, how the setting relationship between the target slip ratios SET and SBT affects the driving feeling of the automobile 1 will be described.

Driving wheel grip force SET and SBT are offset in the vertical direction in FIG. 17 as a whole. Then, in order to increase the clipping force, offset in the upward direction is performed. That is, as a characteristic of the spiked tire, as shown in FIG. 13, since the coefficient of friction μ is increasing up to a slip rate of 0.2 to 0.3, the slip rate of 0.2 to 0.3
The above can be said as long as it is used in the range of 0.3 or less.

Acceleration feeling The acceleration feeling changes by changing the "difference" between SET and SBT. The smaller the "difference", the greater the acceleration feeling. That is, when SET is set to a value smaller than SBT as in the embodiment, the brake control mainly works when the slip ratio is large, and the engine control mainly works when the slip ratio is small. Therefore, SET
If the "difference" between SBT and SBT is reduced, the directions in which the brake control and the engine control work in almost the same distribution will approach.
In other words, the torque generated by the engine is squeezed by the brake to drive the drive wheels, and when the torque is rapidly increased for acceleration, the torque to the drive wheels increases without delay by simply loosening the brake. To do.

Smoothness of acceleration Increase SBT, that is, make it relatively larger than BET. This means that by increasing the priority of the engine control, the smooth torque change, which is an advantage of the engine control, can be more effectively generated.

Stability during cornering SET is made smaller, ie SET is relatively smaller than SBT. As is clear from FIG. 13, this is the slip rate S = 0.2 when the maximum grip force is generated.
In the range of up to 0.3, the target slip ratio is reduced to reduce the grip force of the driving wheel, while increasing the lateral force as much as possible and increasing the bending force.

The above-mentioned characteristics (modes) can be selected manually (mode selection) according to, for example, the preference of the driving vehicle D (mode selection).

In the above-described embodiment, the target slip ratio of the brake SBT is set to be larger than that of the engine SET, so that the brake control is not performed in a small slip state, so that the frequency of use thereof is reduced. In addition, the load on the brake control is reduced even when a large slip occurs. In addition, SBT and S
Since a point (SBC) for stopping the slip control by the brake is provided between the ET and the ET, the brake pressure is sufficiently reduced when the brake control is stopped, so that abrupt torque fluctuation is unlikely to occur.

Although the embodiment has been described above, the present invention is not limited to this, and includes the following cases, for example.

When using a computer, either a digital type or an analog type may be used.

The number of control zones to be set may be changed for each input signal. For example, if the target slip value (SET, SBT) needs to be changed largely even if the signal value changes slightly, the number of control zones may be changed. Should be set to a large number.

The setting of the control zone for one input signal does not need to be equally divided in the range from the minimum value to the maximum value of the signal value. For example, when setting two control zones, the side with the larger signal value is better. When the control value has to be changed more greatly than on the side where the signal value is small, the boundary between the two control zones may be determined on the side where the signal value is large.

How to set the conformance to the control zone, especially 0
The part changed between 1.0 to 1.0 is not limited to the linear function shown in FIGS. 18 to 20, but may be appropriately set like a higher-order function.

The number of input signals used to determine the final control values (SET, SBT) may be 2 or 4 or more.
Of course, the input signal to be used is not limited to that of the embodiment, but the road surface gradient, the load, the shift pattern in the case of a mode variable type automatic transmission that is manually input by the driver, and the like. , Can be measured in various ways.

The slip control may be performed as follows.

For adjusting the torque generated by the engine 6, it is preferable to change and control a factor that most affects the generated output of the engine. That is, it is preferable to adjust the generated torque by so-called load control. In an Otto type engine (for example, a gasoline engine), the air-fuel mixture amount is adjusted, and in a diesel engine, the fuel injection amount is adjusted. Is preferred. However, the load control is not limited to this, and may be performed by adjusting the ignition timing in the Otto type engine or by adjusting the fuel injection timing in the diesel engine. Further, in an engine that performs supercharging, the supercharging pressure may be adjusted.

In the automobile 1, the front wheels 2 and 3 are not limited to drive wheels, and the rear wheels 4 and 5 may be drive wheels, or all four wheels may be drive wheels.

In order to detect the slip state of the drive wheels, it may be detected directly like the rotational speed of the drive wheels as in the embodiment, but in addition to this, the slip state is predicted according to the state of the vehicle, that is, You may make it detect indirectly. Such vehicle states include, for example, an increase in engine generated torque or an increase in rotational speed, a change in accelerator opening, a change in drive shaft rotation, a steering state (cornering), a floating state of the vehicle body (acceleration), Load capacity etc. are considered. In addition to this,
It is also possible to automatically detect or manually input the road surface μ such as the level of the atmospheric temperature, rain, snow, ice burn, etc., and to make the prediction of the slip state of the drive wheels more appropriate.

Brake fluid pressure control circuit and sensors 64, 65 of FIG.
The existing 66 (anti-brake lock system) can be used as the 66.

The slip control of the drive wheels may be performed only by adjusting the torque generated by the engine, or the slip control may be performed mainly by the brake in which the target slip rate SBT for the brake is smaller than the target slip rate SET for the engine.
Further, the slip control may be performed by one of the engine and the brake, and in addition, the slip control by the transmission (particularly, continuously variable transmission) may be performed together.

[Brief description of drawings]

1 to 23 show an embodiment in which the on-vehicle device control device is a slip control device. Figure 1 is the overall system diagram. FIG. 2 is a diagram showing an example of a brake hydraulic pressure control circuit. FIG. 3 is a block diagram when feedback controlling the throttle valve. FIG. 4 is a block diagram when feedback control of the brake is performed. FIG. 5 is a graph schematically showing a control example of the present invention. 6 to 11 and FIGS. 21 to 23 are flowcharts showing control examples of the present invention. FIG. 12 is a graph showing characteristics of throttle opening with respect to accelerator opening when slip control is not performed. FIG. 13 is a graph showing the relationship between the grip force of the driving wheel and the lateral force as a relationship between the slip ratio and the coefficient of friction with the road surface. FIG. 14 is a graph showing correction values when the slip ratio at the start of slip control is corrected according to the steering angle of the steering wheel. FIG. 15 is a graph showing the optimum throttle opening corresponding to the maximum acceleration during recovery control. FIG. 16 is a graph showing the relationship between the slip ratio and the throttle opening when performing the buffer control. FIG. 17 is a graph showing an example of a map used for determining a target slip ratio. 18 to 20 are graphs showing the degree of conformity of the input signal value to the control zone. 1: Automobile 2, 3: Front wheels (drive wheels) 4, 5: Rear wheels (driven wheels) 6: Engine 7: Clutch 8: Transmission 13: Throttle valve 14: Throttle actuator 21-24: Brake 27: Master cylinder 30 , 31: hydraulic pressure control valve 32: brake pedal 61: sensor (throttle opening) 62: sensor (clutch) 63: sensor (gear position) 64, 65: sensor (drive wheel speed) 66: sensor (driven wheel speed) Number) 67: Sensor (accelerator opening) 68: Sensor (steering wheel steering angle) 69: Accelerator 70: Handle SV1 to SV4: Electromagnetic open / close valve U: Control unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A 63-41252 (JP, A) JP-A 60-218290 (JP, A) JP-A 61-282160 (JP, A) JP-A 61- 235234 (JP, A) Actual development Sho 58-98636 (JP, U) Proceedings of the Society of Instrument and Control Engineers Vol. 21, No. 9 (Sho 60.9) “Vehicle speed control with Funy logic controller”

Claims (2)

(57) [Claims] 1. A slip detecting means for detecting a slip value of a drive wheel with respect to a road surface, a torque adjusting means for adjusting a torque applied to the drive wheel, and a traveling state detecting means for detecting a plurality of parameters each indicating a traveling state of a vehicle. Means, a target slip value determining means for determining a target slip value based on a fuzzy rule from input signals relating to a plurality of parameters detected by the traveling state detecting means, and a slip value detected by the slip detecting means. A slip control device for an automobile, comprising: torque control means for controlling the torque adjusting means so that the target slip value determined by the target slip value determining means becomes the target slip value. 2. The target slip value determining means according to claim 1, wherein a plurality of control zones corresponding to signal values of the plurality of parameters are preset for each input signal.
Basic target slip value storage means for storing a basic target slip value for each combination of all control zones, and for each combination, by determining the degree of conformity to the control zone for each input signal value. A suitability determining means for determining the suitability of, a suitability determined by the suitability determining means and the basic target slip value, inference target slip value determining means for determining an inference target slip value for each combination, A final target slip value determining means for determining a final target slip value used by the torque control means from the inferred target slip value for each combination and the suitability for each combination; Slip control device.