JPH02292561A - Automatic speed change control device for automobile - Google Patents

Abstract

PURPOSE:To attain optimum safety running in a driving control by inferring optimum shift action through an input of one or more physical quantities which show a speed of an automobile, throttle opening and the other operational conditions of the automobile. CONSTITUTION:In the case of running, for instance, on a downhill road, because an accelerator is released or loosened, an engine speed is decreased by throttling a throttle opening, and a braking frequency is increased. When a detection signal such obtained is given to a fuzzy inference part 2, the seventh fuzzy rule is started to execute the inference, and a definite output y', which shifts down an automatic speed change mechanism, is output to a shift action control circuit 20. While in the case of curve running on a mountain road or the like, because a steering operational frequency is increased with the engine speed in an intermediate value, the eighth fuzzy rule is started to execute the inference, and a definite output y', which places the automatic speed change mechanism in a condition left as it is, is output to the shift action control circuit 20. Thus by putting the experience of a skilled driver in practical use, a fine speed change control is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an automatic transmission control device for controlling the shift operation of an automatic transmission mechanism in an automobile.

<Prior Art> Conventionally, as this type of automatic transmission control device, there is one that determines a shift point from the relationship between the speed of the vehicle and the throttle opening, and performs shift control by shifting an automatic transmission mechanism at this shift point. .

Problems to be Solved by the Invention> However, in this type of system, the gear change control is performed only based on the speed of the vehicle and the throttle opening, so when driving downhill or on curves, it may cause unfavorable driving conditions for driving operations. occurs.

In other words, when approaching a downhill slope or a curve, the throttle opening should be reduced, and if necessary, downshifting should be performed to reduce speed by engine braking, but with conventional methods, the throttle opening is small. Conversely, upshifts are performed on downhill slopes, or in the middle of curves.

This invention was made with attention to the above problem, and is a method for inferring the shift operation of an automatic transmission mechanism by inputting one or more physical quantities indicating the vehicle speed, throttle opening, and other vehicle operating conditions. The purpose of this invention is to provide a new automatic transmission control device that realizes optimal transmission control for driving operations.

<Means for Solving the Problems> In order to achieve the above object, the present invention uses the speed of the vehicle, the throttle opening, and the A detection unit for detecting and capturing one or more physical quantities indicating the operating state; and inputting each detection value by the detection unit and performing inference calculations according to predetermined control rules to determine shift operations of the automatic transmission mechanism. It was decided that an automatic transmission control device for an automobile would be constituted by an inference section and a control section that shifts the automatic transmission mechanism based on the decision made by the inference section.

Function> When the speed of the vehicle, the throttle opening, and one or more other physical quantities indicating the operating state of the vehicle are given, the inference section calculates the control rules that incorporate the empirical rules of experienced drivers. The inference calculations based on the above are executed, and the optimum speed change control for driving operation is performed. This greatly improves driving operability, especially on downhill slopes and curves.

Embodiment FIG. 1 shows an automatic transmission control device for an automobile according to an embodiment of the present invention, which includes a detection section 1, a fuzzy inference section 2, and a control section 3.

The detection unit 1 includes a speed detection device 4, a throttle opening detection device 5, an engine rotation speed detection device 6, a brake frequency detection device 7, a steering operation frequency detection device 8, and a steering operation angle detection device 9. Detection signals 81 to S6 are provided to sample and hold circuits 10 to 15, respectively.

The speed detection device 4 detects the current speed of the vehicle, and the throttle opening detection device 5 detects the amount of depression of the accelerator. Note that the output of the throttle opening detection device 5 is 0%, which means the accelerator is fully closed, and 100%, which means the accelerator is fully open. The engine speed detection device 6 detects the current engine speed of the automobile, and the brake frequency detection device 7 detects the brake frequency, that is, the ratio of brake operation time within a certain period of time (for example, 10 seconds). The steering operation frequency detection device 8 detects the frequency of steering operation, that is, a certain period of time (for example, 10
Detects the percentage of time during which steering operations other than straight-ahead driving were performed within the time period (seconds). Incidentally, the frequency of braking and steering operation can be easily measured by using, for example, a microcomputer that has a timekeeping function and a calculation function. The steering angle detection device 9 detects the current steering angle.

The sample and hold circuits 10-15 receive detection signals S. from each of these detection devices 4-9. -S. Sample and hold and input the hold value X, ~X. It is then given to the fuzzy inference section 2. The fuzzy inference unit 2 is a calculation entity for executing fuzzy inference, that is, a fuzzy computer, a fuzzy controller, etc., and includes a plurality of rule processing units 16, a MAX synthesis circuit 17, and a defuzzifier 18. .

Each rule processing unit 16 executes fuzzy inference according to a plurality of fuzzy rules using a fuzzy inference antecedent part and a fuzzy inference consequent part, and outputs an inference regarding the shift operation of the automatic transmission mechanism, for example, a shift up for the current shift position. The output indicating whether to shift down or shift down is output to the MAχ synthesis circuit 17.

The fuzzy rule is W! It is a rule based on the experienced rules of driving a car, and as described later, if, the
n Expressed in the form of an (if, then) rule.

The rules of thumb for drivers are listed according to the driving situation:
It is as follows.

A. Driving operations when sudden acceleration is required (1) If the accelerator is depressed deeply and the engine speed is low,
Shift down to obtain sufficient acceleration.

(2) If the accelerator is depressed deeply and the engine speed is at a medium speed, acceleration is performed by shifting as is.

(3) If the engine speed is high with the accelerator depressed deeply, the engine will overrev, so shift up.

B. Driving operations when acceleration is required (4) With the accelerator depressed slightly, accelerate by shifting as is, even if the engine speed is low.

(5) If the accelerator is slightly depressed and the engine speed is medium, shift up and accelerate to save fuel and reduce noise.

(6) If the engine speed is high with the accelerator depressed slightly, shift amplifier is performed to accelerate.

C. Driving operations on a downhill slope (7) If the engine speed is low with the accelerator released, downshift to apply strong engine braking.

D. Driving operations on roads with many curves such as mountain roads (8) If the engine speed is medium and there is torque margin, drive without changing the shift.

E,! ．． Driving operations in a carp (9) When driving around a sharp curve at high speed, changing gears will cause a sudden change in torque, making the car's behavior unstable, so maintain the current shift of 1.

F. Driving operation when coasting at low speed 00) If the shift is high and the engine speed is low, shift down in preparation for the next acceleration.

When the above empirical rules (1) to θω are described in the form of an if, then (if, then) rule, the following fuzzy rules (1) to 00) are obtained.

(1) if XZ =H and x3 =L
then y=D (2) if X2=H and x3=Mt
hen y = M (3) if X2 =Hand X= =
H, then )' = U (4) if X2 = M and Xff
=L, then y=M (5) if Xz =M and x.
=M. then y=tJ (6) if Xz=M and xt
=H, then y=U (7) if xz =L and x.
=Land X4 =H, then y
=D(8) if Xi =M and X
S =l+, then y=M (9) if X+ =F and (x.
=R orxb =L), then
y=M00) if x, =S and
x3=L, then 'l=D Here, H, D, M, etc. are fuzzy labels, and regarding the input X1 regarding the speed of the car, S (S
low) indicates slow, F(F.ast) indicates fast, and regarding the inputs XZ,X, regarding throttle opening and engine speed, L(Low) indicates low and M(
Medium) indicates medium, and H(I{high) indicates high. Regarding inputs x4 and x5 related to brake frequency and steering operation frequency, L indicates less and H indicates more, respectively, and regarding input xb related to steering angle, S (Straight) indicates going straight, and R (Right) indicates clockwise rotation. , L (Lef
t) respectively indicate a left rotation. Furthermore, regarding the output y related to shift operation, M (Medium) is left as is, U (Up) is for upshifting, and D (Down) is
respectively indicate downshifts.

These linguistic expressions are expressed by membership functions, and each human power X, XX . The membership function of is the second
The membership functions of the output y are shown in FIGS. (1) to (6) and in FIG. 2 (7), respectively. In each of these figures, for the variables on the horizontal axis, the vertical axis represents the degree to which these variables belong to the fuzzy set expressed by the above-mentioned linguistic expressions (L, M, etc.) (membership value).

In the fuzzy inference antecedent part of each rule processing unit 16, the degree to which each human power X, ~x6 given from the detection unit 1 matches the membership function corresponding to each fuzzy rule is determined, and The smaller one is selected and given to the fuzzy inference consequent. Then, in the fuzzy inference consequent part, the membership function of the output y is restricted by the selected degree of fitness to obtain, for example, a trapezoidal membership function.

These menharship functions obtained by each rule processing unit 16 are superimposed in a MAX synthesis circuit l7 and a synthesis output u (
y) is generated, and the center of gravity of this combined output is calculated by the defuzzifier 18 as a final output y' and output to the control section 3.

Note that although the above is an explanation of fuzzy inference according to the MIN-MAX calculation rule, the present invention is not limited to this, and fuzzy inference can also be performed according to other calculation rules. Furthermore, the member symbu function is not limited to the shape shown in Figure 2.
Take an arbitrary shape and obtain tRL.

The control section 3 is a section for automatically controlling the shift operation of the automatic transmission mechanism based on the inference result by the fuzzy inference section 2, and the deterministic output y' of the fuzzy inference section 2 is amplified by an amplifier 19 to control the shift operation control circuit. 20-・Give this Schiff 1
- The operation control circuit 20 controls the speed change of the automatic transmission mechanism.

In the automatic transmission control device configured as described above, when driving downhill, for example, the accelerator is released or loosened, so the throttle opening becomes small, the engine speed is low, and the braking frequency becomes high. When such a detection signal is given to the fuzzy inference section 2, the seventh fuzzy rule is activated and inference is executed, and as a result, the final output y' for downshifting the automatic transmission mechanism is changed to shift l.
- It will be output to the operation control circuit 20.

Furthermore, when driving around a curve on a mountain road, the engine speed is medium and the frequency of steering operations is high, so the 8th fuzzy rule is activated and inference is executed, and as a result, the automatic transmission mechanism A definitive output y' that leaves the current state unchanged is output to the shift operation control circuit 20.

In this way, when driving downhill or around curves, detailed shift control is performed that takes advantage of the experience of experienced drivers, achieving optimal driving performance.

<Effects of the Invention> As described above, the present invention prepares an optimal shift operation of an automatic transmission mechanism by inputting one or more physical quantities indicating the vehicle speed, throttle opening, and other operating conditions of the vehicle. As discussed above, it is possible to perform fine-grained speed change control based on the empirical rules of a skilled driver, and achieve the remarkable effects of achieving the purpose of the invention, such as achieving optimal safe driving.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an automatic transmission control device according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing a Menhersimp function of input and output. 1...detection section 2... ．． Fuzzy reasoning part 3
. . . Control unit 4 . . Speed detection device 5. ...
Throntle opening detection W position

Claims (1)

[Claims] An automatic transmission control device for controlling the shift operation of an automatic transmission mechanism in an automobile, which comprises one or more physical quantities indicating the speed of the automobile, the throttle opening, and other operating conditions of the automobile. a detection unit that detects and captures the values, an inference unit that inputs each detected value by the detection unit and performs inference calculations according to predetermined control rules to determine the shift operation of the automatic transmission mechanism; 1. An automatic transmission control device for an automobile, comprising: a control unit that shifts an automatic transmission mechanism based on the control unit.