JP3927640B2 - Control method of constant speed traveling device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the troublesome setting by calculating a first controlled variable for feedback control which is done when actual car speed is comparatively close to target car speed and a second controlled variable for equal acceleration control when actual car speed is comparatively remote from the target car speed and performing resume control by using either of both values which is smaller as a controlled variable. SOLUTION: Target car speed for car speed when a vehicle runs at a fixed speed is stored, and actual car speed is detected to calculate actual acceleration α based on a deviation εbetween the actual car speed and target car speed and actual car speeds which are detected previously and this time. The results of addition obtained by multiplying a constant P by the car speed deviation ε and a constant D by the actual acceleration α are used as a first controlled variable 1 (feedback control) (ST1). The results obtained by multiplying a coefficient K by a value obtained by subtracting target acceleration αm from the actual acceleration αare used as a second controlled variable 2 (equal acceleration control) (ST2). The controlled variables 1, 2 are compared (ST3), and the smaller value is used as a controlled variable (ST4, ST5). As a result, the controlled variable is smoothly continuous, and there are no troublesome setting and abrupt change at a point where control is changed over so that uncomfortable feelings are eliminated.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for controlling a constant speed traveling device for a vehicle.
[0002]
[Prior art]
As a control for a conventional vehicle constant speed travel device, an actual vehicle speed is detected by a vehicle speed sensor, the actual vehicle speed at the start of constant speed travel is stored as a target vehicle speed for constant speed travel, and a relatively narrow vehicle speed above and below the target vehicle speed is stored. The vehicle speed control area is divided into a feedback area consisting of a region, a constant acceleration control area below the lower limit vehicle speed of the feedback area, and a deceleration control area above the upper limit vehicle speed of the feedback area, based on the target vehicle speed and the actual vehicle speed In some cases, a dedicated control equation is provided for each area, and the throttle opening is controlled via an actuator with a calculated control value.
[0003]
Furthermore, there is a resume function as one of the functions of the constant speed traveling device. This is a function that automatically cancels the constant speed traveling and returns to the constant speed again, without automatically setting the vehicle speed and automatically by switch operation. The vehicle can be accelerated or decelerated to return to the constant speed traveling control at the original target vehicle speed.
[0004]
[Problems to be solved by the invention]
However, in the above conventional control method, particularly when the resume is performed from a vehicle speed lower than the target vehicle speed, the absolute value of the deviation between the actual vehicle speed and the target vehicle speed is compared with the switching vehicle speed between the above-described constant acceleration control area and the feedback area. When the absolute value of the deviation is larger than the switching vehicle speed, constant acceleration control is performed to speed up the return, and when the deviation is smaller than the switching vehicle speed, constant speed (feedback) control is performed. ing.
[0005]
In such conventional control, it is necessary to set the switching vehicle speed of the constant acceleration control area and the feedback area according to the characteristics and performance of the vehicle, and when the constants of each area are changed, the switching vehicle speed is accordingly changed. Has to be set again, and there is a problem that setting takes time.
[0006]
[Means for Solving the Problems]
In order to solve such a problem and realize the elimination of the troublesome setting of the switching vehicle speed between different control areas when resuming from a vehicle speed lower than the target vehicle speed, in the present invention, a constant is set. A method for controlling a constant speed traveling device for a vehicle capable of performing resume control for automatically returning after temporarily interrupting the high speed traveling control, wherein the vehicle speed deviation (ε) between the target vehicle speed and the actual vehicle speed is a constant (P) And a value obtained by multiplying the actual acceleration (α) by a constant (D) is calculated as the first throttle opening control amount, and the vehicle speed deviation (α) is calculated from the actual acceleration (α). a value obtained by subtracting a target acceleration (αm) obtained from a preset target acceleration table according to the magnitude of ε) and multiplying by a coefficient (K) is calculated as a second throttle opening control amount, Open first throttle And it shall make pre Symbol resume control towards the one of the small value of the degree control amount and the second throttle opening control amount by the throttle opening control amount.
[0007]
When resume control is performed from a location where the actual vehicle speed is relatively far from the target vehicle speed, constant acceleration control is performed first, and feedback control is performed when approaching the target vehicle speed. Since the smaller one of the control amounts calculated by each of the control values is used, the control amount is switched to the smaller value after the control amount is matched in each control switching. The situation does not happen.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail based on specific examples shown in the accompanying drawings.
[0009]
FIG. 1 is a main part flow diagram showing control based on the present invention, which may be processed as a subroutine for a main routine at the time of resume control in a constant speed traveling device for a vehicle, and the actual vehicle speed is lower than the target vehicle speed. The control amount calculation procedure in this case is shown. Before entering this control flow, the target vehicle speed, which is the vehicle speed at constant speed, is memorized, the actual vehicle speed is detected, the vehicle speed deviation ε between the target vehicle speed and the actual vehicle speed is calculated, and the previous detection The actual acceleration α is calculated from the detected actual vehicle speed and the actual vehicle speed detected this time.
[0010]
In the first step ST1, a value obtained by multiplying the vehicle speed deviation ε by a constant P and a value obtained by multiplying the actual acceleration α by a constant D is defined as a control amount 1 (feedback control) as a first control amount. In the next second step ST2, the value obtained by subtracting the target acceleration αm (constant value) from the actual acceleration α and the coefficient K is set as a control amount 2 (equal acceleration control) as the second control amount. calculate. The target acceleration αm may be obtained from a target acceleration table preset as a data table in accordance with the magnitude of the vehicle speed deviation ε.
[0011]
In the next third step ST3, the control amount 1 and the control amount 2 are compared. If the control amount 1 is smaller, the process proceeds to the fourth step ST4. If the control amount 2 is smaller, the process proceeds to the fifth step ST5. In this way, the smaller value is set as the control amount.
[0012]
This case division is shown below with reference to FIG. The lower part of FIG. 2 shows the throttle opening using the control amount in the present control. The change of the control amount 1 is shown by a solid line in the figure, and the change of the control quantity 2 is shown by an imaginary line in the figure. Has been. Therefore, as shown in the upper part of FIG. 2, in the region A where the actual vehicle speed is relatively far from the target vehicle speed (low vehicle speed), the control amount 2 is used as the control value, and the actual vehicle speed is relatively low relative to the target vehicle speed. The control amount 1 is used as the control value in the region B that is approaching (near the target vehicle speed) and is reversed from the point P1 at which the control amount 1 and the control amount 2 coincide.
[0013]
As described above, the control amount 1 and the control amount 2 obtained by different control equations are compared, and the different control is switched at the point P1 where both coincide, and it is necessary to set the control switching vehicle speed in advance. The troublesome setting of the switching vehicle speed is eliminated. Further, since the control amount becomes the smaller one of the values after matching at the control switching point P1, the control amount continues smoothly before and after the switching point P1. Therefore, since the throttle opening that is the target of the control amount does not change suddenly at the control switching point P1, the movement of the throttle valve does not become discontinuous as in the conventional example, and there is no sense of incongruity.
[0014]
【The invention's effect】
As described above, according to the present invention, when returning from the low vehicle speed at the time of resume to the target vehicle speed, if the vehicle speed deviation is large, quick return is performed with a relatively large control amount by equal acceleration control, and if the vehicle speed approaches the target vehicle speed, It is possible to return to the original constant speed by performing a gradual return by feedback control, and to smoothly switch the control without a sense of incongruity, and to the occupant by a sudden change in the control amount at the control switching point Can prevent discomfort.
[Brief description of the drawings]
FIG. 1 is a main part flow diagram showing control based on the present invention;
FIG. 2 is a diagram showing a change in a control amount of a throttle opening with respect to a change in vehicle speed.

Claims (1)

A control method for a constant speed traveling device for a vehicle capable of performing resume control for automatically returning after temporarily interrupting constant speed traveling control,
The first throttle opening control is obtained by adding a value obtained by multiplying the vehicle speed deviation (ε) between the target vehicle speed and the actual vehicle speed by a constant (P) and a value obtained by multiplying the actual acceleration (α) by a constant (D). The coefficient (K) is calculated by subtracting the target acceleration (αm) obtained from the target acceleration table set in advance according to the magnitude of the vehicle speed deviation (ε) from the actual acceleration (α). a material obtained by multiplying calculated as the second throttle opening control amount, the one throttle opening control towards the one small values of the first throttle opening control amount and the second throttle opening control amount control method for a vehicle for constant speed running apparatus characterized by performing a pre Symbol resume control in the amount.

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