JP2810055B2 - Automotive slip control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an automobile slip control device which prevents slippage of driving wheels of a vehicle to improve running stability.

(Prior Art) The present applicant has disclosed a slip control device for a vehicle of this type, which detects a slip value of a drive wheel of a vehicle with respect to a driven wheel as disclosed in Japanese Patent Laid-Open No. 31866/1988. In addition, by adjusting the drive torque acting on the drive wheels so that the slip value of the drive wheels becomes the target slip value, the effect of excessive drive torque is prevented, and the slip of the drive wheels is effectively suppressed and prevented. I suggest what you do. Thus, in the above-mentioned proposal, the drive torque is adjusted using both the engine output and the brake force acting on the drive wheels, and the brake force is finely adjusted by feedback control.

(Problems to be Solved by the Invention) By the way, in the slip control of the drive wheels as described above, when the drive torque of the drive wheels is adjusted by the braking force,
Since there is a delay in the feedback control of the braking force, the feedback control amount becomes sufficiently large only when the slip of the drive wheel becomes maximum, and thereafter, the slip of the drive wheel is effectively suppressed. As a result, it is desired that the slip be effectively suppressed from the beginning.

The present invention has been made in view of the above point, and an object of the present invention is to provide a sufficiently large braking torque on a drive wheel even at the beginning of the occurrence of a slip of the drive wheel to thereby reduce the slip of the drive wheel. It is an object of the present invention to effectively suppress the slip from the beginning of occurrence and to speed up the convergence of the slip of the drive wheels.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, the feedforward control is performed before the execution of the feedback control based on the slip amount of the drive wheel, and the drive is performed even at the beginning of the drive wheel slip. By sufficiently increasing the reduction amount of the driving torque acting on the wheels, the slip is effectively suppressed even at the beginning of the slip, thereby improving the spin convergence and the feedback control convergence.

That is, as shown in FIG. 1, the first aspect of the present invention comprises a wheel speed detecting unit 13 for detecting a wheel speed, and a driving torque adjusting unit for adjusting a driving torque acting on a driving wheel 6.
22, the throttle valve opening detecting means for detecting the throttle valve opening, the slip amount of the driving wheel and the throttle valve opening obtained from the detection results of the wheel speed detecting means 13 and the throttle valve opening detecting means. Control means 23 for controlling the drive torque adjusting means 22 based on the above. When the control means 23 first detects that the drive wheel is slipping based on the detection result of the wheel speed detection means 13, the control means 23 first adjusts the throttle valve opening to suppress the slip of the drive wheel. After performing the field word control on the drive torque adjusting means 22 with the control amount determined accordingly, following the execution of the feedforward control, the drive is performed so that the slip amount of the drive wheel approaches a preset target slip amount. In the feedforward control, the torque adjusting means 22 performs feedback control, and the drive torque adjusting means 22 controls the drive torque acting on the drive wheels to increase as the throttle valve opening increases.
22 shall be controlled.

Further, as shown in FIG. 1, the solution of the invention of claim 2 includes a wheel speed detecting means 13 for detecting a wheel speed, a driving torque adjusting means 22 for adjusting a driving torque acting on the driving wheel 6, and A gear position detecting means for detecting a gear position of the transmission, and a slip amount of driving wheels obtained from detection results of the wheel speed detecting means 13 and the gear position detecting means and a gear position of the transmission. Control means 23 for controlling the drive torque adjusting means 22; When the control means 23 first detects that a slip has occurred on the drive wheel based on the detection result of the wheel speed detection means 13, the control means 23 firstly sets the gear position of the transmission to suppress the slip of the drive wheel. After performing the feedforward control on the drive torque adjusting means 22 with the control amount determined in accordance with the above, following the execution of the feedforward control, the slip amount of the drive wheels is brought closer to a preset target slip amount. The drive torque adjusting means is feedback-controlled, and in the feedforward control, the drive is controlled such that the lower the gear position of the transmission is, the greater the reduction amount of the drive torque acting on the drive wheels is. Torque adjusting means 22
Shall be controlled.

(Operation) With the above configuration, in the first and second aspects of the present invention, the driving torque adjusting means 22 is controlled by the control means 23, and
Is adjusted, the slip value of the drive wheel 6 with respect to the road surface is controlled to a predetermined target value, and excessive drive torque does not act on the drive wheel, and the slip of the drive wheel 6 is effectively performed. Suppressed and prevented.

If a slip occurs on the drive wheels due to the vehicle entering a road surface having a low friction coefficient, feedback control based on the target slip amount and the actual slip amount is performed at the time of the drive torque adjustment when the slip occurs. By executing the feedforward control not based on the slip amount before the start of the control, the convergence of the slip control and the convergence of the feedback control itself are also improved. Moreover, the amount of reduction in drive torque during the feedforward control is
As the throttle valve as a value related to the driving force of the drive wheels is larger as the opening degree is larger or as the gear position of the transmission is a lower gear position, excessive torque reduction is suppressed,
The driver does not feel uncomfortable due to excessive braking action.

(Effects of the Invention) As described above, according to the vehicle slip control device of the first and second aspects of the present invention, when the slip occurs, before the execution of the feedback control based on the slip amount in order to quickly suppress the slip of the drive wheel. And the feedforward control is performed such that the larger the throttle valve opening degree or the lower the gear position of the transmission, the greater the reduction amount of the driving torque acting on the drive wheels. By doing so, it is possible to suppress excessive torque reduction and make the driver feel uncomfortable due to excessive braking action, effectively suppress the slip even at the beginning of the slip and improve the convergence of the slip. At the same time, the convergence of the slip feedback control can be improved.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

FIG. 2 shows an overall schematic configuration of a vehicle slip control device according to the present invention, wherein 1 is an engine, and 2 is, for example, a forward 4
The engine power shifted by the automatic transmission 2 is transmitted through a propulsion shaft 3, a differential device 4, and a rear axle 5 disposed behind the transmission 2. Rear wheel 6,
6, the rear wheel 6 is driven, and the left and right front wheels 7, 7 are driven wheels.

The intake passage 1a of the engine 1 is provided with a throttle valve 10 for controlling the amount of intake air to adjust the engine output. The throttle valve 10 is an accelerator pedal
There is no mechanical interlocking relationship with 11 and the opening degree is electrically controlled by a throttle actuator 12 composed of a step motor or the like.

Further, in the vicinity of the front, rear, left and right wheels 6, 7, wheel speed sensors 13, 13... Are respectively provided as wheel speed detection means for detecting the rotation speed of the wheels, and the opening degree of the accelerator pedal 11 is determined. An opening sensor 14 for detecting, a steering angle sensor 15 for detecting a steering angle, and an acceleration sensor 16 for detecting acceleration of the vehicle are provided. Thus, each of the above sensors
The detection signals 13 to 16 are input to a controller (control device) 20 having a CPU and the like, and the controller 20 controls the throttle valve 12 by the throttle actuator 12.
The engine output is adjusted by controlling the opening of the engine 10, so that the rear wheels (drive wheels) 6, 6 are prevented from slipping.

Further, a brake actuator 21 for adjusting the brake oil pressure acting on the left and right drive wheels (rear wheels) 6, 6 is connected to the controller 20, and when the wheels spin (slip) of the rear wheels 6, 6, the engine is turned off. In addition to controlling the output, the brake oil pressure is also controlled to suppress the slip.

Therefore, the throttle actuator 12 and the brake actuator 21 adjust the opening degree of the throttle valve (that is, the engine output) and the braking force acting on the driving wheels 6 to adjust the driving torque acting on the driving wheels 6. The driving torque adjusting means 22 is included.

Next, the slip control by the controller 20 will be described with reference to FIGS. 3 to 13. First, from the main flow of FIG. 3, after initialization is performed in step S _M1 , measurement of various data is performed in step S _M2. has a timing, at step S _M3 only when the measurement timing inputs the detection signals from the sensors, the wheel spin of the drive wheels in step S _M4 fourth
The determination is made based on the spin determination flow shown in the figure, and the state of the spin is determined based on the state determination flow shown in FIG. 5 in step S _M5 .

Then, in step S _M6 , it is determined whether or not the traction control (slip control) is being performed based on the value of the traction flag TRCF. If the slip control is not being performed with TRCF = 0, the process proceeds to step S _M7 corresponding to the opening of the accelerator pedal 11. obtains a target throttle valve opening ATAG that, to the value ATAG and the output value THR to a throttle actuator in step S _M8.

On the other hand, if slip control is being performed, steps S _M9 and S _M9
M10 changes the state of the wheel spin to the value of its state flag JF (JF
= 1 immediately after spin generation, JF = 2 immediately after spin convergence), and immediately after spin generation (JF = 1), step
Determining the coefficient of friction of the road surface in S _M11 (hereinafter referred road mu) based on the road surface mu estimating flow Figure 6, first during spin after the slip control begins in step S _M12 (initial flag MF =
In step S _M13 only if 0) in order to greatly reduced control of the throttle valve opening immediately sets the target throttle valve opening TAGETn slip control to a predetermined small opening value SM. On the other hand, if the spin is not the first time (first time flag MF = 1), the target slip ratio is determined based on the target slip ratio determination flow in FIG. 7 in steps _SM14 and _SM15 in order to perform feedback control of the throttle valve opening. And calculates the target throttle valve opening TAGETn corresponding to the target slip ratio in the eighth.
It is calculated based on the target throttle opening calculation flow shown in the figure.

On the other hand, JF = Immediately after second spin convergence, in order to increase return the throttle valve opening instantly step S _M16, the current target throttle valve opening TAGETn, previous value TAGETn-1 and a predetermined recovery opening value FTAG (Step S in FIG. 6)
_C2 (to be described later)).

Thereafter, in order to suppress the excessive brake control of the driving torque at the time of initial spin occurs at step S _M17, with on the basis of the brake control blowing FIG. 10 calculates the brake control amount TB, in the brake control in step S _M18 in order to reduce or hold controlling the throttle valve opening, and corrects the target throttle valve opening TAGETn based on the target throttle valve opening correction flow Figure 12, then the traction control end determination of FIG. 13 in step S _M19 It is determined whether or not to end the slip control based on the flow.

And Thus, actually to control the brake hydraulic pressure acting on the throttle valve 10 and the drive wheels 6, when it becomes the output timing of the control signal in step S _M20, the throttle valve opening control amount THR at step S _M21 Throttle actuator 12
And outputs to the outputs of the brake control amount T _B to the brake actuator 21 in step S _M22, after returning the first-time flag MF to MF = 1 in step S _M23, repeated returning to step S _M2.

Next, the spin determination flow in FIG. 4 will be described. First,
In step S _A1 , the average speed WFN of the front wheel speeds WFR and WFL of the right and left wheels is obtained, and the rear wheel speeds WRR and WRL of the right and left wheels are obtained.
Of the average rear wheel speed WRR, WRL with respect to the average front wheel speed WFN in steps S _{A2 to} S _A4 , the spin determination value S ₁ near the maximum value (S = 1.25). (For example, S ₁ = 1.125). If both are less than or equal to S ₁ , it is a good time when no spin is generated.
_{At A5} , the spin flag SF is set to 0. If only the right rear wheel is spinning, SF = 1 at step S _A6. If only the left rear wheel is spinning, SF = 2 at step S _A7. When the rear wheel is spinning, SF is set to 3 in step S _A8 , and in the case of spin flags SF = 1, 2, and 3, traction flag TRCF is set to 1 in steps S _{A9 to} S _A11 (spin generation Hour) and return.

Next, the state determination flow of FIG. 5 will be described. Step S _B1 to S, respectively preceding and current spin flag SFo at _B3, determine the value of SF, sets the state flag JF = 1 in step S _B4 in case of SFo = 0 and SF ≠ 0 (immediately after spin occurs) And SFO
Step if ≠ 0 and SF = 0 (immediately after spin convergence)
At S _B5 , the status flag is set to JF = 2.

Then, after setting the current value SF of the spin flag to the previous value SFo in step S _B6 , it is determined in step S _B7 whether or not the vehicle is in a stuck state. If not, the stack flag STF = 0 in step _S8. Step S _B9 in the stack
To set STF = 1. In step _SB10 , it is determined whether or not the brake is acting on only one of the left and right wheels (in the case of a split road). If not, the split flag SPF is set to 0 in step _SB11 and the split road is set in step _SB11. In step _SB12 , SPF = 1 is set in step _SB12 , and the routine returns.

In the road μ estimation flow of FIG. 6, the maximum value Gmax of the longitudinal acceleration G of the vehicle immediately after the occurrence of the spin is grasped based on the output of the acceleration sensor 16 in step S _C1 , and then the step S _C1 is performed based on the maximum acceleration Gmax. Three zones ZN1 (0G ≦ Gmax <0.05G) and ZN2 (0.05G ≦ Gmax <0.15) corresponding to the road μ in _C2
G), ZN3 (0.15G ≦ Gmax <0.25G (G is acceleration of gravity))
The recovery opening FTAG in the corresponding zone (the increase in the opening immediately after the convergence of the spin, the basic target slip ratio STAO of the driving wheels in engine output control, the basic target slip ratio STBO of the driving wheels in brake control, the throttle valve opening Opening increase (backup opening) BUF at the time of increase control
Forced return opening SM of immediately after the first spin occurs after slip control starting, and calculates the respective FUZZY control in the step S _C2 (fuzzy control), proportional constant KP in the feedback control of the throttle valve opening, the integral Set the constant KI according to the zone and return.

Next, in the target slip ratio determination flow in FIG. 7, the basic target slip ratio STAO in the output control of the engine and the basic target slip ratio STBO in the brake control, which are calculated based on the road μ estimation flow in FIG. 6, are corrected. In step _SD1 , the accelerator pedal correction gain ACG that increases from the reference value (= 1) according to the accelerator pedal opening ACC
Was calculated, to calculate a vehicle speed correction gain VG in step S _D2 decreases from the vehicle speed reference value depending on (driven wheel speed WFN) (= 1). Moreover, to calculate the steering angle correction gain STG decreases from a steering operation amount in step S _D3 reference value in accordance with (a steering angle) ANG (= 1).

Then, step S _D4 above angle correction gain based in each basic target slip ratio STAO, multiplied correct STBO, each STA of the operation result, and STB, returns.

Next, the target throttle valve opening calculation flow of FIG. 8 will be described. First, in steps S _{E1 to} S _E3 , the left and right driving wheel speeds are set.
The higher speed of WRR and WRL is set as the drive speed SEn to be controlled.

Thereafter, in steps S _E4 and S _E5 , the vehicle speed W of the drive wheel speed SEn
The slip ratio S for FN is set to a predetermined slip ratio S ₃ (for example, S ₃
= 1.02), compared S ₄ (for example, S ₄ = 1.01), in the case of S> 1.02, the opening degree feedback control in Step S _E6 (PI
-PD control) throttle operation amount (increment) ΔTAGET
Is calculated. On the other hand, 1.01> in the case of S, the predetermined value BUF increments progressively forcibly increase control the throttle valve opening (backup control) Subeku, predetermined value determined by the road surface μ estimated flow of FIG. 6 at step S _E7 BUF with throttle operation amount ΔTAGET
Is calculated as Further, when 1.02 ≧ S> 1.01,
To perform control to perform a smooth transition to the feedback control from the backup control (buffer control), calculates the throttle operating amount ΔTAGET in step S _E8.

Then, in step _SE9 , the current target throttle valve opening T
AGETn is calculated from the previous target throttle valve opening TAGETn-1;
It is calculated as an addition value to the throttle operation amount ΔTAGET, and the process returns.

In the engine feedback control flow shown in FIG. 9, the target slip ratio S in the engine control is determined in step S _F1.
Calculates the target driving wheel speed STn by multiplying the vehicle speed WFN to the TA, by subtracting the current driving wheel speed SEn from the target drive velocity STn in step S _F2, and calculates the control deviation ENn.

Then, proportional constants KP and FP, integral constants KI and differential constants FD
It calculates the throttle operating amount ΔTAGET by PI-PD control as in step S _F3, the process returns.

Next, referring to the brake control flow of FIG. 10, first, in step _SG1 , the upper limit value of the brake control amount is set in order to prevent a sudden increase in the brake pressure and a shock caused by the sudden decrease in the brake pressure.
Set up BLM.

Thereafter, in order to control the right brake pressure among the left and right brake pressures, the slip ratio S of the right driving wheel is determined in step _SG2.
(= WRR / WFN) is compared with a predetermined value S ₅ (e.g., S ₅ = 1.0625), S <When small slip 1.0625, and stopping the brake control, the brake control amount of the right driving wheel in step S _G3 T _BR is set to be released (zero value), and in step _SG4 , the right brake flag BFR is set to BFR = 3 (when released).

On the other hand, at the time of a large slip of S ≧ 1.0625, step S _G5
Then, the brake control amount TBR for the right driving wheel is calculated by feedback control (PI-PD control). Then, thereafter, in step _SG6 , it is determined whether or not a wheel spin (slip) of the right driving wheel 6 has occurred at the time of the spin flag SP =
1 (when only the right wheel spins) or SP = 3 (when both wheels spin), and when no wheel spin occurs,
In step _SG7 , a brake control flag FBF _R indicating that brake control is being performed during the first wheel spin is set to FBF _R = 0 (non-control).

On the other hand, when wheel spin occurs, steps S _{G8 to} S
_{In G12} , only after the spin generation (early generation) (JF = 1) where the wheel change speed ΔWRR of the speed of the right driving wheel 6 is equal to or more than the set value (≧ 0) (ΔWRR ≧), the spin is changed after the start of the slip control. On condition that the spin is the first spin (MF = 0), the brake control flag FBF _{R is set} to FBF _R = 1, and the brake control amount T ′ _BR at the initial _stage of the first spin generation is calculated in step _SG13 . Here, the brake control amount T ′ _BR at the initial stage of the first spin occurrence is determined to be a constant value irrespective of the slip ratio S of the drive wheels 6. However, the brake control amount _T'BR is set such that the larger the driving force of each driving force of the driving wheels 6 (that is, the throttle valve opening and the gear ratio of the transmission), the larger the driving force so as not to give a shock to the vehicle due to an excessive braking action. It is set to a large value, and is determined by the following equation.

T ' _BR = K _TH · TAGATn-1 + K _GP · GP Here, TAGETn-1 is the previous target throttle valve opening in slip control, and K _TH is a coefficient corresponding to the throttle valve opening (the larger the opening, the larger the change. Do), GP is gear position, K _GP
Is a coefficient according to the gear position GP (the lower the gear, the greater the change)
It is.

In steps _SG14 and _SG15 , the brake control amount _T'BR at the initial stage of the first spin occurrence obtained above is equal to or greater than the brake control amount _TBR by feedback control ( _TBR ≤ T ').
_BR ), this brake control amount T ′ _BR is output to the brake actuator 21.

Thereafter, in step S _G16 , the brake control amount T _BR becomes T
_{When BR} > 0, it is determined that the brake pressure is being increased (particularly, when the pressure is maintained at T _BR = 0), and this control amount T _BR is determined at steps _SG17 and _SG18.
There when exceeding the BLM (maximum variation width) upper limit is limited to the upper limit value BLM, right brake flag BFR in step S _G19
Is set to BFR = 1 (when pressure is increased). On the other hand, the lower limit value when determined that the braking pressure reduction when the brake control amount T _BR of T _BR <0, where the control quantity T _BR in step S _G20 and S _G21 exceeds the lower limit -BLM -BLM Step S
_{In G22} , the right brake flag BFR is set to BFR = 2 (when pressure is reduced).

In step _SG23 , when the brake pressure acting on the drive wheel 6 is equal to or higher than the set value, the value P of the brake pressure acting on the drive wheel 6 is first set in order to forcibly reduce or maintain the throttle valve opening. _R is estimated and calculated based on the right brake pressure estimation flow in FIG.

Thereafter, the brake control pressure T _BR for the left driving wheel is calculated in step _SG24 in the same manner as described above, and the process returns.

Next, the flow of estimating the right brake pressure in FIG. 11 will be described.
Step S _H1 and determine the value of the right brake flag BFR in S _H2, BFR = 1 (increase during pressurization) and BFR = 2 in (in a vacuum), step S following equation estimated brake pressure P _R in _H3 P _R = Calculated as P _R + ΔP _R. Here, [Delta] P is [Delta] P _R in variation _{R = K B · T BR (} K
_B is a coefficient and T _BR is a brake control amount.) Then, step S _H4 and the previous value of the current estimated brake pressure P _R in S _H5 P _RO
At the same time, the elapsed time T is initialized to T = 0, and the routine returns.

On the other hand if it is not increasing during pressurization and depressurization in brake pressure, i.e. at the time of opening of the brake, it confirmed not to be estimated brake pressure P _R is approximately P _R = 0 at step S _H6, Step S _H7
And the estimated brake pressure P _R in S _H8 calculated by the equation _{P R = P R1 · exp (} -T / T P), by measuring the time elapsed T, the process returns. Here, P _R1 brake pressure immediately before the brake open, the T _P is the time constant of the hydraulic characteristics determined by the braking system or the like.

Furthermore, the estimated brake pressure at step S _H6 P _R approximately P _R =
If it is 0, the estimated brake pressure P _R is set in steps S _{H9 to} S _H11.
Is set to P _R = 0, the value P _R is set to the previous value P _RO , the elapsed time T is initialized to T = 0, and the routine returns.

Next, FIG. 12 explains the target throttle valve opening correction flow. This correction flow corrects the throttle valve opening in order to prevent hunting of both because the driving force acting on the driving wheel 6 during the slip control of the driving wheel 6 is controlled by both the engine output and the brake pressure. To control. That is, if the throttle valve opening is opened during the brake pressure increase, a hunting phenomenon between the brake and the engine output occurs in which an increase in the driving force caused by the opening is suppressed by the brake, and this is to be prevented. Also, even if the brake is released, the brake pressure does not immediately become zero, and if the throttle valve opening is opened during this time,
When the same phenomenon as described above occurs and the brake pressure becomes zero, the throttle valve opening is too open, which results in the slip of the drive wheel 6 again. When the pressure is acting, correction control is performed so that the opening of the throttle valve 10 is reduced or maintained.

That is, when the vehicle is stuck in steps S _I1 and S _I2 (ST
In the case of F = 1) or when traveling on a split road (SPF = 1), it is necessary to open the throttle valve while increasing the brake pressure, so that the throttle valve opening correction control is not performed.
In step _SI3 , the spin state flag JF is set to 0 (when no spin occurs), and the routine returns.

In addition, in steps S _I4 and S _I5 , during the brake pressure increase to the left or right drive wheel 6 (BFR = 1 or BFL = 1), the step
At S _I6 , the target throttle valve opening TAGETn in the slip control of the driving wheel 6 is set smaller than the previous value TAGETn−1 by the set return amount BT (may be set to be held instead), and Steps S _I7 and JF = 2 at S _I8 (immediately after spin convergence)
Except in the case of (1), that is, when JF = 1 (immediately after the occurrence of spin), JF is reset to 0 (when no spin occurs), and the recovery control of the throttle valve opening immediately after the spin convergence (the third control).
Predetermined addition control opening FTAG) is postponed in step S _M16 in FIG then returns.

Further, in steps S _{I9 to} S _I12 , if the brake to the left or right drive wheel 6 is being depressurized (BFR = 2 or BFL = 2) or the brake is being released (BFR = 3 or BFL = 3), the step
If the estimated brake pressure P _R or P _L of the higher of S _I13 to S _I15 in the left and right drive wheels 6 exceeds the set minimum value Pmin is
The present target throttle valve opening value TAGETn in the slip control in step S _I16 holds set equal to the preceding value TAGETn-1 (may be set so as to decrease the degree of opening), then step S _I17 to S JF = 2 at _I18 (immediately after spin convergence)
(That is, when JF = 1 (immediately after spin generation))
JF is reset to 0 (when no spin occurs), and the control is returned as postponing the recovery control of the throttle valve opening immediately after the spin convergence.

If the brake pressure of the left and right drive wheels 6 is not increasing, decreasing, or releasing, the spin state flag JF is set to 0 (when no spin occurs) in step _SI19 , and the _routine returns.

Finally, the traction control end determination flow in FIG. 13 will be described.

First determine the target throttle valve opening ATAG according to the accelerator pedal position ACC in step S _J1.

Thereafter, in step S _J2 , the target throttle valve opening A
The value of TAG is determined, and when about ATAG = 0, the traction control is terminated. At steps S _{J3 to} S _J5 , each flag is reset and output to the throttle actuator 12 is performed.
THR is set to a zero value, and this is set as a control target value TAGETn.

On the other hand, when ATAG ≠ 0, the target throttle valve opening ATAG according to the accelerator pedal opening is further set in step S _J6 .
The target throttle valve opening TAGETn in the slip control is compared with the target throttle valve opening TAGETn. If ATAG> TAGETn, the slip control is continued. In steps S _J7 and S _J8 , the target throttle valve opening TAGETn in the slip control is set to the control lower limit value ( If it is less than the forced drop opening value SM immediately after the first spin occurs)
After limiting the lower limit value SM, the target throttle valve opening TAGETn throttle actuator 12 to a step S _J9
Output value THR.

On the other hand, when ATAG ≦ TAGETn, in order to control the throttle valve 10 with the target opening value ATAG corresponding to the accelerator pedal depression opening, this value ATAG is set as the output value THR in step S _J10 , and this is controlled. The target value is TAGETn.

Then, the current control target value TAGETn as the control target value TAGETn-1 in the previous Step S _J12, returns.

In the above flow, the throttle valve opening detecting means or the gear position detecting means for detecting the opening degree of the throttle valve or the gear position of the transmission as a value relating to the driving force of the driving wheel is constituted. Further, based on the slip amount of the drive wheel 6 and the throttle valve opening or the gear position of the transmission determined from the detection results of the wheel speed detecting means 13 and the throttle valve opening detecting means or gear position detecting means. The control means 23 controls the drive torque adjusting means 22. When the control means 23 first detects that the drive wheel 6 is slipping based on the detection result of the wheel speed detection means 13, the control means 23 firstly opens the throttle valve to suppress the slip of the drive wheel 6. The drive torque adjusting means 22 is fed-forward controlled by a control amount determined according to the degree or the gear position of the transmission, and after the execution of the feed-forward control, the slip amount of the drive wheel 6 and the set target are set. On the basis of the slip amount, the driving torque adjusting means 22 adjusts the slip amount of the drive wheel 6 to approach the target slip amount.
And in the feedforward control, the larger the throttle valve opening is,
Alternatively, the drive torque adjusting means 22 is controlled such that the lower the gear position of the transmission is, the greater the reduction amount of the drive torque acting on the drive wheels 6 is.

Therefore, in the above embodiment, as shown in FIG. 14, after the slip control of the drive wheels 6 is started, the drive wheels 6
And the slip rate S as shown by the symbol A
There the initial slip to the driving wheels 6 becomes spin determination values S ₁ or more occurs, is feed forward control so that the opening degree of the throttle valve 10 is greatly reduced instantaneously to a small opening value SM, with it S < after being feedforward control so as to return only the recovery opening value FTAG returning to S _1, the feedback control of the drive wheel 6 (PI-PD control) is performed. Then, in order to prevent the slip ratio S of the drive wheels from greatly dropping below the target value STA, buffer control and backup control are sequentially performed. When the rotational speed of the drive wheels starts to increase, the buffer control is thereafter performed. After that, feedback control (PI-PD control) is performed again. As a result, the slip ratio S of the drive wheels 6 converges favorably to the target slip ratio STA.

Then, the accelerator pedal depression opening decreases, and the target throttle valve opening ATAGn corresponding to the accelerator pedal is equal to or less than the target throttle valve opening TAGETn for slip control (ATAGn ≦ TAGET).
After the time point indicated by the symbol B in the figure in the state of n), the throttle valve opening is controlled to the target throttle valve opening ATAG corresponding to the accelerator pedal, and the drive wheel is driven when the accelerator pedal 11 is fully closed. 6 is stopped. The above is the operation of only the throttle valve opening control in the slip control of the drive wheels 6.

Next, the characteristic operation of the present invention will be described. Now, as shown in Figure 15, the slip ratio S rotational speed of the driving wheels 6 becomes higher beyond the spin determination value S _1, when the initial slip drive wheels occurs (state shown by symbol A) is , Control means 23
The opening of the throttle valve 10 is controlled by the control, and as in the above-described basic operation, the opening is instantaneously reduced to a small opening value (TAGETn = SM). When the spin converges, the opening of the throttle valve 10 is increased by the coverage opening FTAG.
Thereafter, feedback control is performed by the throttle operation amount ΔTAGETT. At the same time, conventionally, although a braking force acts on the drive wheel 6 as indicated by a broken line, the brake control amount T _BR is initially small, and becomes large when the rotational speed of the drive wheel 6 becomes close to the maximum, Because of the response delay, the rotation speed of the drive wheel 6 does not immediately decrease, and it takes time to converge on the target slip ratio STA. However, in the present invention, even at the beginning of the start of the slip control, a sufficiently large brake control amount T ′ _{BR of} a predetermined value according to the driving force of the driving wheel 6 acts immediately as shown by the solid line, and this temporarily (ΔWRR). (Only during ≧), the rotation speed of the drive wheels 6 can be quickly reduced with a small braking force, and the target slip ratio STA can be converged satisfactorily in a short time.

Incidentally, after the brake control rate T'BR predetermined value is applied temporarily, the brake control amount by the feedback control T _BR
Works, the slip of the drive wheels 6 starts to converge and the brake pressure is reduced, but when the brake pressure exceeds the set minimum value Pmin, the spin state flag JF becomes JF = Since JF is forcibly set to 0 (no spin is generated) from 1 (immediately after spin is generated) and the recovery control of the throttle valve opening is prohibited, hunting between the brake pressure and the engine output can be prevented.

In addition, if the drive wheel 6 slips for the second time or later during the slip control, as shown in FIG. 16, the throttle valve opening is feedback-controlled (PI-PD control) and gradually decreases. The brake pressure also gradually increases from a zero value by feedback control unlike the first spin. In this case, the brake pressure starts to decrease immediately after the convergence of the slip of the drive wheel 6, and even if the speed of the drive wheel 6 reaches the target value once, the target throttle valve opening is opened in a situation where the brake pressure is still being reduced. Side, the opening of the throttle valve 10 starts to open as shown by the broken line in the figure, the engine output increases, and hunting between the brake pressure and the engine output occurs, and the brake pressure becomes zero. In this case, the throttle valve opening may be too large, causing the drive wheels 6 to re-slip, as indicated by the broken line in FIG. However, in this embodiment, until the brake pressure P _R is set minimum value Pmin, since the target throttle opening TAGETn is maintained or reduced control, is prevented such hunting described above, the drive wheel 6 Re-slip can be prevented beforehand.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 16 show an embodiment of the present invention, FIG. 2 is an overall schematic diagram, FIGS. 3 to 13 are flow charts showing a drive wheel slip control by a controller, and FIGS. FIG. 16 is an operation explanatory view. 1 ... engine, 6 ... drive wheel, 10 ... throttle valve,
11 ... accelerator pedal, 12 ... throttle actuator, 13 ... wheel speed sensor, 20 ... controller (control device), 21 ... brake actuator, 22 ... drive torque adjusting means, 23 ... control means.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60T 8/58 B60K 41/20 F02D 29/02 301-311

Claims (2)

(57) [Claims] 1. A wheel speed detecting means for detecting a wheel speed; a driving torque adjusting means for adjusting a driving torque acting on a driving wheel; a throttle valve opening detecting means for detecting a throttle valve opening; Control means for controlling the drive torque adjusting means based on the slip amount of the drive wheel and the throttle valve opening obtained from the detection result of the detection means and the throttle valve opening detection means, and the control means When it is detected for the first time that a slip has occurred on a drive wheel based on the detection result of the wheel speed detection means, a control determined according to the throttle valve opening to suppress the slip of the drive wheel is performed first. After performing the feedforward control on the drive torque adjusting means by the amount, the slip amount of the drive wheel is adjusted to a predetermined target slip after the execution of the feedforward control. The drive torque adjusting means is feedback-controlled so as to approach the throttle amount, and in the feedforward control, the larger the throttle valve opening is, the larger the reduction amount of the drive torque acting on the drive wheels is. A vehicle slip control device for controlling the drive torque adjusting means. 2. A wheel speed detecting means for detecting a wheel speed; a driving torque adjusting means for adjusting a driving torque applied to a driving wheel; a gear position detecting means for detecting a gear position of a transmission; Means and control means for controlling the drive torque adjusting means based on the slip amount of the drive wheel obtained from the detection result of the gear position detection means and the gear position of the transmission, wherein the control means comprises: When it is detected for the first time that slippage has occurred in the drive wheels based on the detection result with the speed detection means, a control amount determined according to the gear position of the transmission to suppress slippage of the drive wheels. After performing the feedforward control on the drive torque adjusting means, the slip amount of the drive wheels is brought closer to a preset target slip amount following execution of the feedforward control. Thus, the drive torque adjusting means is feedback-controlled, and at the time of the feedforward control,
A slip control device for an automobile, wherein the drive torque adjusting means is controlled such that the lower the gear position of the transmission is, the greater the reduction amount of the drive torque acting on the drive wheels is.