JP3277740B2 - Automatic speed control device for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic speed control device for a vehicle for automatically controlling a running speed of a vehicle (hereinafter, also referred to as a vehicle speed).

[0002]

2. Description of the Related Art A conventional automatic speed control device for a vehicle is disclosed in Japanese Patent Application Laid-Open No. 4-132845 (first conventional example). This means that, based on the deviation between the target vehicle speed and the actual vehicle speed, a target driving force that matches the two is calculated, and the throttle valve opening is controlled so that the actual driving force matches the target driving force. To improve the vehicle speed control performance. "

As a known general control method (second conventional example), an “approximate zeroing control method” is known. This involves estimating the disturbance applied to the controlled object using a disturbance estimator (disturbance observer) using a dynamic model of the controlled object based on the manipulated variable to the controlled object and the output of the controlled object. By correcting the operation amount based on the result, the influence of disturbance is eliminated.

Further, there is a technique disclosed in Japanese Patent Application Laid-Open No. Hei 1-331136 (third conventional example). In order to achieve a target engine torque, a target throttle valve opening is obtained using engine performance data stored in advance, and control is performed so that the actual throttle valve opening matches the target throttle valve opening. is there.

[0005]

Here, in the automatic speed control device for a vehicle, a case in which the first conventional example and the second conventional example are combined to control the vehicle speed to the target vehicle speed with higher accuracy. Considering this, the disturbance estimator estimates the running resistance (sum of slope resistance, air resistance, and rolling resistance), which is the disturbance applied to the vehicle, and calculates the target driving force obtained from the vehicle speed deviation based on the estimation result. By performing the correction, it is possible to achieve the vehicle speed control performance that is not affected by the change in the running resistance.

However, the above combination has the following problems. That is, since the driving force of the vehicle to be controlled is finite, when a driving force exceeding the driving force (engine braking force in the case of a negative value) is required during vehicle speed control, an error is generated inside the disturbance estimator. It continues to accumulate, and the subsequent vehicle speed control performance is reduced. That is, for example, assume a situation in which the vehicle enters a steep ascending slope during constant vehicle speed control, and the driving speed is insufficient even with the maximum driving force of the vehicle, so that the vehicle speed falls below the target value. In this situation, errors continue to accumulate inside the disturbance estimator, and the target driving force is greatly corrected to the plus side. Overshoot will occur (see FIG. 8A ).

On the other hand, during automatic speed control (hereinafter also referred to as "constant vehicle speed control"), the vehicle enters a steep downhill, and even if it has the maximum engine braking force of the vehicle, the engine braking force is insufficient and the vehicle speed becomes the target. Let's assume a situation where the value is exceeded. In this situation, errors continue to accumulate inside the disturbance estimator, and the target driving force is greatly corrected to the negative side. This causes an undershoot (see FIG. 8B ).

Further, even when considering the combination of the first conventional example and the third conventional example, there is the following problem. That is, due to the non-linear characteristics of the engine performance, there is an operation region in which substantially the maximum engine output torque is generated even if the throttle valve opening is not fully opened. When the target throttle valve opening is determined from the target engine torque using this nonlinear engine characteristic data, the throttle valve opening is set to a value equal to or greater than the opening that is assumed in advance to obtain the maximum engine output torque. Not be. Therefore, even if there is a variation in the actual engine characteristics of the vehicle and there is a difference in the maximum torque, the maximum engine torque of the engine is not always required.
That is, the maximum driving force may not be obtained (see FIG. 9).

The present invention has been made in view of such circumstances, and has a vehicle in which a target driving force is calculated so as to obtain a target vehicle speed, and an engine is controlled so as to obtain the target driving force. In a vehicle speed control device for a vehicle, an error in a calculation for estimating a running resistance that occurs when a target driving force is set to a value that cannot be actually achieved is suppressed, thereby performing high-accuracy automatic vehicle speed control. It is a first object of the present invention to provide an automatic speed control device for a vehicle which can perform the following.

In a vehicle speed control apparatus for a vehicle, a target driving force is calculated so as to obtain a target vehicle speed, and a throttle valve opening is controlled so as to obtain the target driving force. When setting the valve opening, the target throttle valve opening is determined using engine characteristic data expanded so that the engine torque always corresponds one-to-one over the entire throttle valve opening, instead of the conventional nonlinear engine characteristic data. By setting, even if the engine characteristics of the actual vehicle vary, the target throttle valve opening can be set with high accuracy, so that the automatic speed control of the vehicle with high accuracy can be performed. A second object is to provide an automatic speed control device for a vehicle.

It is an object of the present invention to further improve the accuracy and simplify the automatic speed control device for a vehicle.

Therefore, according to the first aspect of the present invention, as shown in FIG. 1, based on the actual vehicle speed and the target vehicle speed of the vehicle, the target driving force is calculated so as to make the two substantially coincide. arithmetic means, and the calculated target driving force, on the basis of a running resistance estimated value of the vehicle, to the final target driving force calculating means for calculating a final target driving force, the computed final target driving force engine Maximum driving force and maximum
Estimating and calculating the running resistance value of the vehicle based on the final target driving force correcting means for obtaining a corrected final target driving force by limiting with a small driving force , the corrected final target driving force, and the actual vehicle speed. And running resistance calculating means.

[0013]

[0014] According to a second aspect of the invention, as shown in FIG. 2, on the basis of the actual vehicle speed and the target vehicle speed of the vehicle, and the target driving force calculation means for calculating a target driving force that is substantially coincident to each other A final target driving force calculating means for calculating a final target driving force based on the calculated target driving force and an estimated running resistance of the vehicle; and
Limiting the maximum driving force and the minimum driving force determined from the engine characteristics to obtain a corrected final target driving force, a final target driving force correction unit, the corrected final target driving force, an actual vehicle speed, And a final target driving force calculated by the final target driving force calculating means in one-to-one correspondence with the engine torque throughout the throttle valve opening. Target throttle valve opening setting means for setting a target throttle valve opening based on the engine characteristic data extended so that the actual throttle valve opening substantially matches the target throttle valve opening. And throttle valve control means for controlling the throttle valve.

According to a third aspect of the present invention, the upper limit value and the lower limit value are set based on the engine torque when the throttle valve is fully opened and when the throttle valve is fully closed set for each engine speed. The invention according to claim 4 is a model matching vehicle speed control that calculates the target driving force such that the actual vehicle speed substantially matches the target vehicle speed in accordance with a response characteristic of a predetermined reference model. The calculation is performed using a means.

[0016]

According to the first aspect of the present invention having such a configuration, the maximum driving force (upper limit value) determined from engine characteristics and the like is determined with respect to the final target driving force used in the running resistance estimation calculation by the running resistance calculation means. Even if the final target driving force is set to a value that cannot be actually obtained by correcting (restricting) with the minimum driving force (lower limit value) , an error occurs in the estimation calculation of the running resistance. Not to be. Thus, for example, during an automatic speed control, when the vehicle enters a steep ascending slope, the driving force is insufficient even with the maximum driving force of the vehicle, and the vehicle speed decreases with respect to the target value. Even when the vehicle enters a steep downhill and has the maximum engine braking force of the vehicle, even if the engine braking force is insufficient and the vehicle speed greatly exceeds the target value, an error is generated inside the running resistance calculating means. Does not accumulate, and even after the road gradient returns to flat, the running resistance calculating means functions quickly to control the vehicle speed to the target vehicle speed without overshooting or undershooting. Accordingly, highly accurate automatic speed control of the vehicle can be performed.

[0017]

According to the second aspect of the present invention, there is provided the first aspect.
Calculated by the final target driving force calculating means
Target throttle valve opening using the final target driving force
Setting of target throttle valve opening by adding
Engine torque is required for the entire throttle valve opening
Extended engine characteristic data to provide one-to-one correspondence
To calculate the target throttle valve opening by using
To As a result, for example, the vehicle speed decreases from the target vehicle speed.
On steep ascending slopes, the throttle valve is fully open.
The engine can be fully opened up to
Without being affected by variations in the characteristics of the engine.
Maximum driving force can be obtained. Therefore, high precision
The automatic speed control of the vehicle can be performed.
In addition, the second target throttle valve opening degree setting means sets the setting accuracy.
Use the target driving force taking into account the running resistance value for improvement.
To set the target throttle valve opening.
No.

According to the third aspect of the present invention, the upper limit value and the lower limit value can be set with high accuracy by a relatively simple configuration. According to the fourth aspect of the present invention, the target driving force can be calculated with high accuracy by a relatively simple configuration.

[0020]

Embodiments of the present invention will be described below.FIG.
Is a system of an automatic speed control device according to an embodiment of the present invention.
FIG. thisFIG.In a vehicle not shown
An automatic transmission 30 is installed on the output side of the mounted engine 20.
Have been killed. This automatic transmission 30
The fluid type torque converter 40 interposed on the side
The teeth connected to the engine 20 via the torque converter 40
The vehicle-type transmission 50 and various transmission elements in the gear-type transmission 50
Hydraulic actuator (not shown)
).

The operating oil pressure for the hydraulic actuator (not shown) is controlled through various electromagnetic valves (not shown), and includes a CPU, a ROM, a RAM, a digital port,
Control unit for automatic transmission 12 consisting of microcomputer with built-in / D port, various timers, etc.
Shifts to a target gear position by a combination of ON and OFF of the various electromagnetic valves.

The automatic transmission control unit 12 travels at a constant speed via the signal line A at a gear position (3rd or OD (overdrive)) during constant vehicle speed control (ie, during automatic speed control). To the control unit 1. On the other hand, the constant-speed traveling control unit 1 described later sends a constant-speed traveling control signal via the signal line B to the automatic transmission control unit 12 during the constant-speed traveling control, An OD (overdrive) cancel request signal is sent at the time of constant speed traveling via the vehicle. The automatic transmission control unit 12 performs the speed change control based on a command from the constant speed traveling control unit 1 during the constant speed traveling control. That is, during normal traveling, the control unit 12 for automatic transmission transmits signals (TV signals) from various sensors.
O, Vsp, etc.), and outputs a shift signal for turning on / off the electromagnetic valve in accordance with the target shift speed, controls a shift operation in the automatic transmission 2, and performs constant-speed running control. During the shift, the target shift speed is determined based on the signal from the constant speed traveling control unit 1 and the like, and a shift signal for turning on / off the electromagnetic valve is output in accordance with the target shift speed. The operation will be controlled. The communication between the control unit 1 for constant-speed traveling and the control unit 12 for the automatic transmission is the simplest parallel type in the present embodiment, but may be another type.

The constant-speed traveling control unit 1 includes a one-chip microcomputer (or a multiple-chip microcomputer realizing the same function) including a CPU, ROM, RAM, digital port, A / D port, various timers, and the like. It is constituted by a throttle actuator drive circuit 1-3. Note that, as in the present embodiment, it is preferable to include a fail-safe shutoff circuit 1-2 that cancels the constant-speed traveling control when an abnormality occurs.

Various signals are input to the constant speed control unit 1. The various signals are signals from the switches 2 to 7 operated by the driver, the vehicle speed sensor 8, the throttle sensor 9, and the crank angle sensor 10, and the like. The start or release of the high-speed running control is determined.

Here, the main switch (MAIN S)
W) 2 is a constant speed traveling permission switch for permitting power supply to the constant speed traveling control unit 1 and the throttle actuator drive circuit 1-3. The set switch (SET SW) 3 is a switch for starting constant-speed traveling control and setting a set vehicle speed. The accelerate switch (ACC SW) 4 is a switch for increasing the set (target) vehicle speed, and is a coast switch (COAS).
T SW) 5 is a switch for lowering the set (target) vehicle speed. Cancel switch (CANSEL SW)
Reference numeral 6 denotes a switch for releasing the cruise control, and a brake switch (BRAKE SW) 7 is a switch for releasing the cruise control when the driver depresses the brake pedal.

The vehicle speed sensor 8 is a vehicle speed sensor using an electromagnetic pickup, and generates a pulse signal in synchronization with the output shaft of the automatic transmission 30 and the like. The output shaft rotation speed is detected by counting or measuring the cycle, and the actual vehicle speed Vsp is detected based on the detection result and the final reduction ratio. The actual vehicle speed Vsp detected in this manner is used for calculating the operation amount of the throttle actuator 11, determining the shift timing during the constant speed traveling control, and the like.

The throttle sensor 9 is a potentiometer type sensor which is provided in the intake system of the engine 20 and detects the opening of a throttle valve 21 which opens and closes in conjunction with an accelerator pedal (not shown). Is output to the constant-speed traveling control unit 1 and the unit 1 performs A / D conversion to detect the actual throttle valve opening TVO. The throttle valve opening TVO detected in this manner is used for servo control of the throttle actuator 11, estimation of running resistance, and the like.

The crank angle sensor 10 is a sensor used for measuring the engine speed. The throttle actuator 11 is a negative pressure type throttle actuator, and adjusts the negative pressure of a vacuum pump driven by a motor or the like by opening and closing a plurality of solenoid valves (not shown) that can communicate with the atmosphere. , The throttle valve 21 can be forcibly operated without depending on the accelerator operation.

Here, the constant-speed traveling control performed by the constant-speed traveling control unit 1 in the present embodiment will be described .
This will be described with reference to the flowchart of FIG. In this embodiment, the control unit 1 for cruising at a constant speed comprises a target driving force calculating means according to the present invention, a final target driving force calculating means,
Software functions are provided as final target driving force correction means, running resistance calculation means, first target throttle valve opening setting means, second target throttle valve opening setting means, throttle valve control means, and model matching vehicle speed control means. ing.

First, at P1, a calculation is performed based on the count value of the number of pulses from the vehicle speed sensor 8 counted during 100 msec, and the average actual vehicle speed VSP during 100 msec is measured. Further, an arithmetic operation is performed based on the count value of the number of pulses from the crank angle sensor 10 counted during 100 msec, and the average engine speed Ne for 100 msec is measured. Further, the microcomputer reads an analog signal value from the throttle sensor 9 using an A / D conversion function in the microcomputer, performs a predetermined calculation, and measures the throttle valve opening TVO.

At P2, the state of the digital I / O port connected to the cancel switch 6 and the brake switch 7 is monitored. The process proceeds to P8 in order to cancel, and if both are OFF, the process proceeds to P3 in order to permit the constant speed traveling control. At P3, the state of the digital I / O port connected to the set switch 3 is monitored.
In the case of F, proceed to P7.

At P4, the current actual vehicle speed Vsp is stored as the target vehicle speed Vspr. At P5, constant-speed running control is being performed (A
An ASCD operation flag indicating that the SCD is operating is set (= 1). In P6, the fail-safe power cutoff circuit 1
Corresponding to the digital I / O so that
Set a predetermined bit of the port register.

At P7, the ASCD operation flag is checked, and if it is in the set state (= 1), it is determined that the cruise control is being performed, and the program proceeds to P10. If it is not set (= 0), the process proceeds to P8. At P8, each flag and variable are initialized. In P9, the fail-safe power shutoff circuit 1
A predetermined bit of the register of the corresponding digital I / O port is cleared so that -2 is turned off.

In P10 to P14, the target vehicle speed Vspr is
In order to make the actual vehicle speed Vsp coincide, the final target driving force y1 is calculated by using a well-known linear control technique “model matching technique” and “approximate zeroing technique”. First, an outline of the vehicle speed feedback compensator will be described using a pulse transfer function. The transfer characteristic of the controlled object is represented by the pulse transfer function P
If (z-1) is set, the controller is as shown in FIG . z is a delay operator, and when it is multiplied by z-1, it becomes a value one sample cycle earlier. C1 (z-1) and C2 (z-1) are disturbance estimators based on the approximate zeroing method, and suppress the influence of disturbance and modeling errors. C3 (z-1) is a compensator based on a model matching method, and makes the response characteristics of the controlled object coincide with the characteristics of the reference model H (z-1).

If a portion where the target driving force is input and the actual vehicle speed is an output is to be controlled, P (z ^-1 ) is represented by an integral element P1 (z ^-1 ) and a dead time element P2 ( z ^-1 ) = z ^-2
The product of

[0036]

(Equation 1)

If the reference model is a first-order low-pass filter with a time constant Ta ignoring the dead time of the control object,
3 is the following constant. C3 = K = [1−exp (−T / Ta)] · M / T At P10, the following calculation corresponding to the model matching compensator is performed to obtain the target driving force y4. However, data y (k
-1) indicates data y (k) one sample cycle earlier.

Y4 (k) = K · (Vspr (k) −Vsp (k)) In P11, the robust compensator C which is a part of the disturbance estimator is used.
The following operation corresponding to 2 (z ^-1 ) is performed. y3 (k) = γ · y3 (k−1) + (1−γ) · M / TV
sp (k) − (1−γ) · M / T · Vsp (k−1) In P12, the final target driving force y1 (k) is obtained by correcting the target driving force y4 by the following equation. However, y2 (k-2) is P14
This is data two sample cycles before y2 (k) obtained by Incidentally, y2 (k-2) -y3 (k) is a running resistance estimated value.

Y1 (k) = y4 (k) −y3 (k) + y2 (k−2) In P13, each table data in which the engine torque value when the throttle valve is fully opened and fully closed is stored for each engine rotational speed. By using this, the maximum engine torque Temax and the minimum engine torque Temin are determined. Further, the maximum driving force Fmax and the minimum driving force Fmin are obtained by using the following equation. Gm is
The transmission gear ratio, Gf is the final gear ratio, and Rt is the effective radius of the tire.

Fmax = (Temax · Gm · Gf) / Rt Fmin = (Temin · Gm · Gf) / Rt Furthermore, the final target driving force y1 (k) is set to the upper limit F
y5 (k) is obtained by limiting with max and lower limit value Fmin. That is, if y1 (k)> upper limit Fmax, then y5 (k) = upper limit Fmax, and if y1 (k) <lower limit Fmin, y5 (k)
(k) = lower limit value Fmin, and if upper limit value Fmax ≧ y1 (k) ≧ lower limit value Fmin, then y5 (k) = y1 (k).

At P14, the following operation corresponding to the compensator C1 (z ^-1 ) as a low-pass filter which is a part of the disturbance estimator is performed. y2 (k) = γ · y2 (k−1) + (1−γ) · y5 (k−1)) At P15, the target engine torque Ter is calculated from the final target driving force y1 (k). Gm is the transmission gear ratio,
Gf is the final gear ratio, and Rt is the effective radius of the tire.

Ter = (y1 · Rt) / (Gm · Gf) Further, a target throttle valve opening is tabulated from the target engine torque Ter using an engine non-linear characteristic data map stored in advance for each engine speed. Calculate.
For example, as shown in FIG. 6 , an extended data map is used in which the engine torque always corresponds to the entire throttle valve opening. In FIG. 6 , the solid line part is the original engine characteristic data, and the dotted line part is the expanded data.

In step P16, a known control method such as PI (proportional integration) control is used to eliminate the deviation Δ based on the throttle valve opening deviation Δ (= target opening TVOR-actual opening TVO). Calculate the pulse width (Tvac, Tvent) of each output (drive) to the vacuum pump and the atmospheric release solenoid valve of the negative pressure type throttle actuator 11.

At P17, the output pulse width Tvac of the vacuum pump and the output pulse width Tvent of the solenoid valve for releasing to atmosphere are written into the register for pulse output in the control unit 1 for constant speed traveling. With this flow, the following operation and effect can be obtained. That is, the disturbance estimator configured by the “approximate zeroing method” accurately estimates disturbance (running resistance) based on the difference between the output of the controlled object model and the actual output of the controlled object.

In particular, even in the case where the vehicle speed is reduced to a target value due to a shortage of the driving force even with the maximum driving force of the vehicle during a constant vehicle speed control due to a steep ascending slope. The final target driving force input to the disturbance estimator is limited so as not to exceed the actual maximum driving force, and does not become a large target driving force value that cannot be actually obtained. Is not accumulated. Therefore,
Even after the road gradient returns to flat, the disturbance estimator functions quickly to control the vehicle speed to the target vehicle speed without overshooting (see FIG. 7A ).

Conversely, there is a situation in which the vehicle enters a steep downhill during the constant vehicle speed control and has the maximum engine braking force of the vehicle, but the engine braking force is insufficient and the vehicle speed greatly exceeds the target value. Even if it is assumed, the final target driving force value input to the disturbance estimator is limited so as not to fall below the actual minimum driving force value, and a small target driving force value (large engine braking Therefore, no error is accumulated inside the disturbance compensator. Therefore, even after the road gradient returns to flat, the disturbance estimator functions promptly to converge the vehicle speed to the target vehicle speed without undershoot ( FIG. 7B ) .
reference).

Further, based on the target engine torque obtained from the final target driving force value whose upper and lower limit values are not limited, the engine torque value and the throttle valve full opening region are expanded so as to correspond one-to-one. The target throttle valve opening is obtained using the engine non-linear characteristic data map ( FIG. 6 ), so that even on a steep ascending slope where the vehicle speed decreases from the target vehicle speed, the throttle valve is completely opened until the throttle valve is fully opened. Can be opened. Therefore, the maximum driving force of the engine can be obtained without being affected by the variation in the engine characteristics.

In the above embodiment, the engine speed may be estimated from the engine load such as the throttle valve opening and the basic fuel injection amount Tp. Instead of the engine torque, a parameter (Tp, intake air flow rate, or the like) representing an engine load other than the throttle valve opening can also be used. Further, in the above embodiment, the running resistance calculating means of the present invention and the second target throttle valve opening degree setting means are combined.
Although the configuration ( corresponding to claim 2 ) has been described, the one provided with only the running resistance calculating means of the present invention (corresponding to claim 1).
In this case, the throttle valve does not need to be forcibly controlled. For example, a throttle valve bypass passage may be provided, and the engine torque may be controlled by a flow control valve (so-called ISD) provided in the bypass passage. ) Can also achieve the first object of the present invention .

[0049]

As described above, according to the first aspect of the present invention, the upper limit value obtained from the engine characteristics and the like with respect to the final target driving force used for the running resistance estimation calculation by the running resistance calculation means. Corrected by the lower limit and (lower limit)
In the case where the final target driving force is set to a value that cannot be actually obtained, no error occurs in the estimation calculation of the running resistance. The error is not accumulated, and even after the road gradient returns to flat, the running resistance calculating means functions promptly to control the vehicle speed to the target vehicle speed without overshooting or undershooting. Automatic vehicle speed control with high accuracy can be performed.

According to the second aspect of the present invention, by providing the first target throttle valve opening setting means, when setting the target throttle valve opening, the engine torque always corresponds to the entire throttle valve opening in a one-to-one correspondence. The target throttle valve opening is obtained by using the extended engine characteristic data (linear), so that the throttle valve can always be completely opened up to the full opening, so that the engine characteristic variation is reduced. The maximum driving force of the engine can be extracted without being affected by the influence of the engine, so that highly accurate automatic speed control of the vehicle can be performed.

According to the second aspect of the present invention , the upper limit value and the lower limit value can be set with high accuracy by a relatively simple configuration. According to the third aspect of the present invention, the target driving force can be calculated with high accuracy by a relatively simple configuration.

[Brief description of the drawings]

FIG. 1 is a block diagram of the invention according to claim 1;

FIG. 2 is a block diagram of the invention according to claim 2;

FIG. 3 is a system diagram of an automatic speed control device according to an embodiment of the present invention .
FIG.

FIG. 4 is a flowchart showing automatic speed control in the embodiment .
Chart.

FIG. 5 is a vehicle speed feedback compensation in the embodiment .
The figure which explained the outline | summary of the container using the pulse transfer function.

FIG. 6 shows extended engine characteristics in the embodiment .
The figure which shows data.

FIG. 7 (A) is an example of the above embodiment on an uphill slope.
FIG. (B) shows the same on a downhill.
The figure explaining the effect in the said Example.

FIG. 8 (A) shows a problem on an uphill slope in a conventional device.
FIG. (B) shows a downhill in the conventional device.
FIG. Shift range in conventional embodiment
9 is a flowchart showing shift control at the time of switching.

FIG. 9 is a view showing conventional engine characteristic data.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control unit for constant speed driving 8 Vehicle speed sensor 9 Throttle sensor 10 Crank angle sensor 11 Throttle actuator 12 Control unit for automatic transmission 20 Engine 21 Throttle valve 30 Automatic transmission

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60K 31/00 F02D 29/02 301 F02D 41/04 310

Claims (4)

(57) [Claims] 1. A target driving force calculating means for calculating a target driving force based on an actual vehicle speed of a vehicle and a target vehicle speed so as to make the two substantially coincide with each other; A final target driving force calculating means for calculating a final target driving force based on the estimated value; and determining the calculated final target driving force from engine characteristics.
Limiting the maximum driving force and the minimum driving force to obtain a corrected final target driving force, based on the corrected final target driving force and the actual vehicle speed. An automatic speed control device for a vehicle, comprising: running resistance calculating means for estimating and calculating a resistance value. 2. A target driving force calculating means for calculating a target driving force based on the actual vehicle speed of the vehicle and the target vehicle speed so as to make the two substantially coincide with each other; A final target driving force calculating means for calculating a final target driving force based on the estimated value; and determining the calculated final target driving force from engine characteristics.
Limiting the maximum driving force and the minimum driving force to obtain a corrected final target driving force, based on the corrected final target driving force and the actual vehicle speed. Running resistance calculating means for estimating and calculating a resistance value; and engine characteristics expanded so that the engine torque and the final target driving force calculated by the final target driving force calculating means correspond one-to-one over the entire throttle valve opening. Target throttle valve opening setting means for setting a target throttle valve opening based on the data, and controlling the throttle valve such that the actual throttle valve opening substantially matches the target throttle valve opening. An automatic speed control device for a vehicle, comprising: a throttle valve control means that performs the control. 3. Based upon the set throttle valve fully opened every engine speed and fully closed engine torque, according to claim 1 or claim and sets the maximum drive force and minimum driving force 3. The automatic speed control device for a vehicle according to 2 . Wherein said target driving force, using a model matching vehicle speed control means for said actual vehicle speed along a response characteristic of a predetermined reference model is calculating the target driving force that substantially coincides with the target vehicle speed The automatic speed control device for a vehicle according to any one of claims 1 to 3 , wherein the calculation is performed.