JPH01202540A - Cruise control device - Google Patents

Abstract

PURPOSE:To quickly and smoothly perform the convergence to the target car speed when the control is restarted by interrupting the feedback control and returning the target throttle opening at that time to the initial value when an accelerator is depressed during the cruise control.. CONSTITUTION:When the automatic cruise is set by a switch 2, a control device 7 initially sets the target throttle opening in response to the target car speed set by an accelerating switch 3 and a setting switch 4 and feedback-corrects the target throttle opening in response to the deviation between the actual car speed by a detector 1 and the target car speed and drives an actuator 8 and performs the automatic cruise control. When an accelerator pedal is depressed, the feedback control is interrupted, the corrected target throttle opening is returned to the initial value, when the accelerator pedal is released, the target throttle opening is used as the current control target, and the feedback control is restarted. The convergence property to the target car speed can be thereby improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cruise control device that automatically causes a vehicle to travel at a constant speed.

The amount of Ul is generally independent of the drive system that opens and closes the engine's throttle valve using the vehicle's accelerator pedal.

The actuator in the cruise control device opens and closes the throttle valve independently, allowing acceleration by depressing the accelerator pedal for purposes such as overtaking even during cruise control, and after completing the overtaking. By releasing the drive system using the accelerator pedal, cruise control can be continued.

In conventional cruise control devices, a target vehicle speed is set to match the vehicle speed when the O1-Cruise switch is set, and the target vehicle speed is set according to [11! After initially setting the throttle valve opening, the target vehicle speed is constantly compared with the actually detected vehicle speed, regardless of accelerator pedal operation, and the correction amount for the throttle valve opening is calculated based on the difference. Feedback control is performed to correct the throttle valve opening.

However, with such a loose control device, it is meaningless to execute feedback control when the accelerator pedal is depressed during cruise control and the vehicle is traveling at a speed higher than the target vehicle speed, and during that time, the actual vehicle The initially set target throttle valve opening is corrected according to the difference between the vehicle speed and the target vehicle speed, and the corrected throttle valve opening becomes inappropriate, causing the accelerator pedal system to be released. The appropriately corrected throttle valve opening, which is the current control target when cruise control is continued, becomes unstable, resulting in a decrease in controllability.

The present invention was made in consideration of the above points, and when the accelerator pedal is pressed during cruise control,
While correcting the target throttle valve opening according to the difference between the target vehicle speed and the actual vehicle speed, the actual throttle valve opening is adjusted as appropriate to maintain the actual vehicle speed at 0I7IA vehicle speed. To provide a cruise control device that can stably restart feedback control with a constant throttle valve opening as the current control target when the throttle valve is released.

In order to achieve the objective, the old present invention initially sets a target throttle valve opening according to the target vehicle speed, and then adjusts the correction amount of the throttle valve opening according to the difference between the target vehicle speed and the actually detected vehicle speed. In a cruise control device that employs feedback control means for correcting a target throttle valve opening by adjusting the throttle valve opening, the cruise control device includes means for detecting that an accelerator pedal of a vehicle is depressed and that the accelerator pedal is subsequently released; means for interrupting the feedback control when it is detected that the throttle valve has been stepped on, and maintaining the target throttle valve opening at that time at the initially set target throttle valve opening;
Thereafter, when it is detected that the accelerator pedal has been released, the feedback control is resumed according to the previously held target throttle valve opening degree.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an example of the basic configuration of a cruise control device according to the present invention, which includes a vehicle speed detector 1 that detects the actual running speed of the vehicle, and a cruise control operation command and release according to on/off operations. An auto cruise main switch 2 that gives commands, an acceleration switch 3 that gives cruise control acceleration commands and resume commands, a set switch 4 that gives cruise control desired vehicle speed set commands and deceleration commands, and engine throttle valve opening A throttle valve opening detector 5 detects the opening, a control device 7 reads the detection signals of the detectors 1 and 5 and command signals from the switches 2 to 4 and executes cruise control, and a control device 7 executes cruise control according to the control signals. An actuator 8 drives the throttle valve to open and close.

The control device 7 includes an input interface 71, a CP
U72. ROM 73 and RAM 74 for control. A constant memory 75 in which predetermined control characteristics necessary for cruise control are stored in advance. It consists of an output interface 76.

, FIG. 2 shows an example of the contents of the RAM 74, and FIG. 3 shows an example of the contents of the constant memory 75.

The actuator 8 is configured to rotate a step motor by an appropriate amount in the forward or reverse direction via a driver in accordance with a control signal output from the control device 7, thereby driving the throttle valve in the opening or closing direction. It has become.

Further, FIG. 4 shows a specific example of the control configuration within the control device 7.

In the cruise control device configured as described above, when the auto cruise main switch 2 is turned off, the auto cruise plug in the RAM 74 of the control device 7 is reset and the cruise control is released. There is.

At this time, under the control of the CPU 72, the constant memory 7
The reference throttle valve opening memory 751 in No. 5 is selected, and the reference throttle valve opening preset in that memory is stored in the RAM 74 as the target throttle valve opening.
The target throttle valve opening degree is registered in the target throttle valve opening degree memory 747. In the reference throttle valve opening degree memory 751, a throttle valve opening degree corresponding to the idle rotation speed of the engine is set.

Further, the actual throttle valve opening detected by the throttle valve opening detector 5 is registered in the actual throttle valve opening memory 746 in the RAM 74.

Then, the value registered in the target throttle valve opening degree memory 747 and the value registered in the actual throttle valve opening degree memory 746 are compared, and the throttle valve opening degree control unit 91 appropriately controls the actuator 8 according to the difference. A drive command is issued, whereby the actual throttle valve opening is maintained equal to the throttle valve opening corresponding to the engine's idle speed.

In this case, it is possible to independently drive the opening and closing of the throttle valve by the accelerator pedal of the vehicle, regardless of the control by the actuator 8 to hold the throttle valve at the idle position when the loose control is released. It is now possible to do so.

Further, when the auto cruise main switch 2 is turned on, the auto cruise plug in the RAM 74 in the control bag v717 is set, and the cruise control set state is entered.

As a result, under the control of the CPU 72, the actual traveling speed of the vehicle detected by the vehicle speed detector 1 when the set switch 4 is operated is registered in the actual vehicle speed memory 744 in the RAM 74, and this is used as the target vehicle speed. It is initialized in memory 745.

At the same time, the set throttle valve opening degree memory 752 in the constant memory 75 is selected. The set throttle valve opening degree memory 752 stores target throttle valve opening characteristics with respect to the target vehicle speed. As the characteristic of the target throttle valve opening degree with respect to the target vehicle speed, for example, as shown in FIG. 5, the throttle valve opening characteristic corresponding to the vehicle speed when the vehicle is traveling on a flat road is adopted.

Therefore, when setting the throttle valve opening degree memory 752
According to the target throttle valve opening characteristic for the target vehicle speed stored in the target vehicle speed memory 7,
The target throttle valve opening corresponding to the target vehicle speed set to 45 is read out and initialized in the target throttle valve opening memory 747.

At this point, the actual throttle valve opening degree memory 74
Since the contents of 6 are zero, the actuator 8 is driven by the throttle valve opening control section 91 and the throttle valve is rapidly moved to the initially set target opening position.

Thereafter, the actual vehicle speed and actual throttle valve opening are detected at the sampling period set in the sampling timer 92 (for example, 0.5 seconds), and feedback is provided to maintain the actual vehicle speed at the target vehicle speed. Control is performed as follows.

That is, after the set switch 4 is operated, the difference between the actual vehicle speed detected by the vehicle speed detector 1 and updated and registered in the actual vehicle speed memory 744 and the target vehicle speed registered in the target vehicle speed memory 745 is calculated as the vehicle speed deviation. It is found in section 93. The obtained difference is then given to the throttle valve opening correction amount calculating section 94, where the constant memory 7
5 is multiplied by a certain constant read from the multiplier memory 753 to calculate the throttle valve opening correction amount. Then, the calculated throttle valve opening correction amount is added to the target throttle valve opening previously registered in the target throttle valve opening memory 747 in the adding section 95, and the corrected new target throttle valve opening is obtained. The target throttle valve opening degree is updated and registered in the target throttle valve opening degree control section 747. Furthermore, at that point, the actual throttle valve opening detected by the throttle valve opening detector 5 is registered in the actual throttle valve opening memory 746, so the actual throttle valve opening and the target throttle valve are corrected. The actuator 8 is controlled through the throttle valve opening controller 91 so that the actual throttle valve opening at that time becomes equal to the corrected target throttle valve opening. is driven appropriately.

In this way, the target throttle valve opening is initially set according to the preset characteristics in accordance with the target vehicle speed that is set when the set switch 4 is turned on, and the actual vehicle speed is set using the throttle valve opening as the starting point. Cruise control is started by correcting the target throttle valve opening based on the deviation from the vehicle speed and then performing feedback control so that the actual throttle valve opening becomes equal to the corrected throttle valve opening. The deviation between the target vehicle speed and the actual vehicle speed immediately after is reduced (or averaged), a drop in vehicle speed or hunting is prevented, and convergence to the target vehicle speed is performed quickly and smoothly.

Note that when the auto cruise main switch 2 is turned off, the cruise control in the control unit r117 is immediately canceled.

Next, a case in which the target vehicle speed is adjusted during autocruise will be described below.

When the driver operates the acceleration switch 3 during autocruise, an acceleration signal is generated during the operation period. In response to the generation of an acceleration signal. CPU 72 selects acceleration initial incremental memory 754 in constant memory 75 .

The acceleration initial incremental memory 754 stores the characteristics of incremental addition according to the actual vehicle speed at that time.

The incremental correction value read from the initial acceleration incremental memory 754 is added to the stored value in the target throttle valve opening memory 747.

Therefore, the value stored in the target throttle valve opening memory 747 increases by the incremental correction value, the step motor in the actuator 8 rotates by an angle corresponding to this, and the throttle valve opening becomes equal to the original acceleration. is realized.

On the other hand, due to the generation of the acceleration signal, the acceleration signal duration timer 96 is driven, and the elapsed time during which the acceleration switch 3 is operated is counted. Further, at the same time as the acceleration signal is generated, the acceleration pattern memory 755 in the constant memory 75 is selected.

The acceleration pattern memory 755 stores characteristics of incremental correction values necessary for acceleration according to the elapsed time. The incremental correction value read from the acceleration pattern memory 755 is further added to the stored value in the target throttle valve opening degree memory 747.

As a result, the target value of the throttle valve opening becomes larger than the actual opening, so the CPU 72 drives the actuator 8 as described above to increase the throttle valve opening as the elapsed time increases. I'll let you do it.

When the desired acceleration is completed, the operation of the acceleration switch 3 is stopped, and the acceleration signal disappears, the CPU 72 stores the actual vehicle speed at that time in the target vehicle speed memory 745 as the target vehicle speed.

At the same time, the accelerator decrement memory 756 in the constant memory 75 is selected. The accelerator reduction memory 75
6 stores the characteristics of the throttle valve opening correction amount in the closing direction, which should be executed immediately after the acceleration signal disappears, in accordance with the actual vehicle speed.

Therefore, when acceleration is completed, the accelerator decrease memory 7
The closing direction correction amount read from 56 is added to the stored value in the target throttle valve opening degree memory 747, and the actuator 8 is driven so as to reach the corrected target throttle valve opening degree.

In this way, after the acceleration signal disappears, the throttle valve opening degree is once reduced by a certain amount determined by the actual vehicle speed at that time. This prevents overshoot of the actual vehicle speed after the acceleration operation.

Thereafter, cruise control for the new accelerated target vehicle speed is executed in the same manner as described above.

Further, when the driver operates the set switch 4 during autocruise, a deceleration signal is generated during the operation period.

In response to the generation of this deceleration signal, the CPU 72 controls the deceleration dark reference opening degree memory 758 in the constant memory 75 (or
Instead, reference throttle valve opening memory 751)
Select. The deceleration dark reference opening degree memory 758 stores a value close to the throttle valve opening degree when the engine is idling.

As a result, a value close to the throttle valve opening during idling operation is registered in the target throttle valve opening memory 747.

As a result, the value stored in the target throttle valve opening memory 747 becomes smaller than the value stored in the actual throttle valve opening memory 746, and the throttle valve is driven in the closing direction, realizing the initial deceleration of the vehicle. Ru.

In this case, the throttle valve opening value stored in the deceleration dark reference opening degree memory 758 may be a fixed value, or may be one that changes depending on the actual vehicle speed at that time.

When the desired deceleration is completed and the operation of the set switch 4 is stopped, the deceleration signal disappears, and the CPU 72 selects the post-deceleration opening degree memory 757 in the constant memory 75 accordingly.

At the same time, the actual vehicle speed at that time is stored in the target vehicle speed memory 745 as the target vehicle speed.

The post-deceleration opening degree memory 757 stores the characteristics of the throttle valve opening degree that should be set immediately after the deceleration signal corresponding to the actual vehicle speed disappears.

The value read from the post-deceleration opening degree memory 757 is stored in the target throttle valve opening degree memory 747 as the target throttle valve opening degree at that time.

Note that the throttle valve opening value in this case is based on the throttle valve opening memory 7 at the time of setting for the same vehicle speed.
It is preferable to select a value smaller than the value stored in the reference throttle valve opening degree memory 751 and larger than the value stored in the reference throttle valve opening degree memory 751.

In this way, the throttle valve opening degree is set to a scheduled value determined by the actual vehicle speed at that time after the deceleration signal disappears. Further, thereafter, cruise control for the new target vehicle speed that has been decelerated is executed in the same manner as described above.

In the loose control device as described above, in particular, the present invention includes a means for detecting that the accelerator pedal of the vehicle is depressed and that the accelerator pedal is subsequently released, and a means for detecting that the accelerator pedal is depressed. means for interrupting feedback control when the accelerator pedal is detected to maintain the target throttle valve opening at that time at the initially set target throttle valve opening; The feedback control is restarted according to the target throttle valve opening held at the target throttle valve opening.

Specifically, under the control of the control device ff17, a high-level signal is generated when the accelerator pedal is depressed, and a signal from the accelerator pedal switch 6 (see FIG. 1) is inverted to a low-level signal when the accelerator pedal is released. A target that is initially set when the set switch 4 stored in the initial set target throttle valve opening memory 748 of the RAM 74 is turned on when it is detected that the accelerator pedal of the vehicle is depressed in accordance with a signal. The throttle valve opening degree is read out and registered in the target slot 1 valve opening degree memory 747. Control equipment again! 17, and then when it is detected that the accelerator pedal of the vehicle is released in accordance with a signal from the accelerator pedal switch 6, the initially set target registered in the target throttle valve opening memory 747 is set. Feedback control is restarted with the throttle valve opening as the current control target.

Note that the initial setting target throttle valve opening degree memory 748
When the target throttle valve opening degree is initially set in the target throttle valve opening degree memory 747, it is simultaneously stored.

Therefore, during cruise control, when the accelerator pedal is depressed for temporary acceleration overtaking, etc., feedback control is interrupted, and during that time the target throttle valve is adjusted according to the difference between the target vehicle speed and the actual vehicle speed. The opening is no longer inappropriately corrected, and feedback control is stably restarted with the same initial target throttle valve opening when the accelerator pedal is released after acceleration overtaking. You will be able to do so. In addition, the actual vehicle speed and target throttle valve opening memory 7 at the end of acceleration overtaking
The difference from the initially set target throttle valve opening degree registered in the target vehicle speed memory 745 becomes small, and the convergence to the target vehicle speed registered in the target vehicle speed memory 745 can be performed quickly and smoothly.

Further, as mentioned above, there is a method for detecting whether or not the accelerator pedal is depressed using the accelerator pedal switch 6 or the like (in addition, it is possible to use a means for detecting whether or not the accelerator pedal is depressed based on the engine speed). In the control table 7, the rotational position of the step motor in the actuator 8, that is, the commanded throttle valve opening under cruise control and the actual throttle valve opening are compared, without using any
If the actual throttle valve opening is larger than the throttle valve opening corresponding to the rotational position of the step motor, the accelerator pedal is being depressed during cruise control; otherwise, the accelerator pedal is being depressed. It is also possible to make a logical judgment if there is no such thing.

Furthermore, to ensure this determination, we compare the rotational position of the step motor with the actual throttle valve opening and check whether the difference between the target vehicle speed and the actual vehicle speed at that time is greater than a certain value. Depending on the condition, whether the accelerator pedal is depressed during cruise control,
It is also possible to logically determine whether it has been released.

In other words, in this case, the actual throttle valve opening is larger than the throttle valve opening corresponding to the rotational position of the step motor, and the difference between the target vehicle speed and the actual vehicle speed at that time is greater than a certain value. Sometimes, I try to think of it as if the accelerator pedal is being depressed for the first time.

FIG. 6 shows an example of the control flow at that time.

Here, when the set switch 4 is turned on.

In the first step, the actual vehicle speed V detected by the vehicle speed detector l at that time is the minimum vehicle speed V+m1n (for example, 35K
A determination is made as to whether or not the value is greater than or equal to (set in M/H).

In that case, if V≧VfiIin, setting of control target values and various detections necessary for cruise control, such as registration of target vehicle speed, registration of target throttle valve opening, detection of actual throttle valve opening, calculation of vehicle speed deviation, etc. After reading the device output, the process moves to the next second step.

Further, if it is V (Vain), the ON operation of the set switch 4 is canceled and the auto-cruise cancellation state is set.

In the next second step, if the vehicle has an automatic transmission, check to see if the inhibitor contact is grounded, that is, if the select lever is set to the drive position, or if the vehicle is in manual transmission. If the transmission is for the transmission MT, it is determined whether the clutch switch is turned on or not.

In that case, if the AT→drive position is set and the MT→clutch switch is on, the process moves to the next third step; otherwise, the autocruise is released.

In the next third step, it is determined whether the brake switch of the vehicle is in the on state.

In that case, if the brake switch is in the on state, the auto cruise is released, and if not, the process moves to the next fourth step.

In the next fourth step, in the case of a manual transmission vehicle, it is determined whether or not the gear is out of gear (no load).

At that time, 1. For example, when the gear is engaged, the ratio dN between the engine rotational speed differential amount fidN and the actual vehicle speed differential amount dV
/dV is almost constant, so by checking the value it is possible to determine whether or not the gear is out of gear.

In that case, unless the gear is out of gear, auto cruise processing,
After selecting auto cruise processing among various processing such as acceleration/deceleration processing, coast processing, and resume processing,
After the auto-cruise flag is set and the auto-cruise lamp is turned on, the process moves to the first, fifth step.

Furthermore, if the gear is out of gear, the auto cruise is released.

In the next fifth step, the rotation angle O5H of the step motor that drives the actuator 8 to open and close the throttle valve and the actual throttle valve opening DrH
It is determined whether or not the accelerator pedal is depressed by making a comparison with .

In that case, taking into account the hissing of the throttle valve opening caused by the step motor, when the condition ≦θ0τH is satisfied for osM+θ, it is determined that the accelerator pedal has been depressed, and the next step is performed in the sixth step. Move to.

In the next sixth step, it is determined whether the absolute value I VprHl of the difference between the target vehicle speed and the actual vehicle speed is greater than the hysteresis VFL.

In this case, if l VprFl > VR, it is determined that the accelerator pedal is indeed depressed.

The auto cruise flag is reset.

Thereafter, the process from the start is repeated.

Further, if 1VorFl≦v, it is determined that the accelerator pedal is not depressed, and the determination result that the accelerator pedal is depressed in the previous fifth step is invalidated.

Thereafter, the process from the start is repeated.

Also, in the previous fifth step, ofM+θk〉0
If τH, it is determined that the accelerator pedal is temporarily released, and the process moves to the next seventh step.

In the next seventh step, taking into account the threshold Oo of the absolute value of the difference between the target throttle valve opening and the actual throttle valve opening, it is determined whether 05M+00>θ[1( will be carried out.

In that case, if θ5H'+ 00≦θTM, it is assumed that the accelerator pedal is depressed, and the determination result that the accelerator pedal is released in the previous fifth step is invalidated, and the auto cruise flag is is put into a reset state.

Thereafter, the process from the start is repeated.

Further, if 05M+00>θrH, it is assumed that the accelerator pedal is indeed released, and the processing from the start is repeated thereafter.

The cruise control device according to the present invention corrects the target throttle valve opening according to the difference between the target vehicle speed and the actual vehicle speed when the accelerator pedal is depressed during cruise control. The feedback control that maintains the actual vehicle speed at the target vehicle speed by adjusting the actual throttle valve opening as appropriate is interrupted, the corrected target throttle valve opening is returned to the initial setting value, and the accelerator is When the pedal is released, feedback control is restarted using the initially set target throttle valve opening as the current control target.

This prevents the target throttle valve opening from being inappropriately corrected while the accelerator pedal is pressed, and also stabilizes the cruise control and quickly converges to the target vehicle speed when feedback control is resumed. It has the excellent advantage of being able to be carried out smoothly.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing an embodiment of a cruise control device according to the present invention, FIG. 2 is a diagram showing a table in the RAM in the same embodiment, and FIG. 3 is a diagram showing a constant memory table in the same embodiment. 4 is a block diagram showing a specific control configuration example in the control device of the same embodiment, FIG. 5 is a diagram showing the characteristics of throttle valve opening with respect to vehicle speed, and FIG. 6 is a control flow according to the present invention. It is a figure showing an example. 1... Vehicle speed detector 2... Auto cruise main switch 3... Acceleration switch 4... Set switch 5... Throttle valve opening detector 6... Accelerator pedal switch 7... Control device 8... Actuator Figure 1 Figure 2 Figure 3 Figure 5 O Immediate Figure 6

Claims (1)

[Claims] After initially setting the target throttle valve opening according to the target vehicle speed, the correction amount of the throttle valve opening is calculated according to the difference between the target vehicle speed and the actually detected vehicle speed, and the target throttle valve opening is corrected. In a cruise control device having a feedback control means, means for respectively detecting that an accelerator pedal of a vehicle is depressed and that the accelerator pedal is subsequently released;
A means for interrupting feedback control when it is detected that the accelerator pedal is depressed and maintaining the throttle valve opening at that time at an initially set target throttle valve opening; 1. A cruise control device comprising means for restarting feedback control in accordance with a previously held target throttle valve opening degree when a previously held target throttle valve opening degree is detected.