JPH09164859A - Throttle control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a throttle control device which can prevent the overshoot of car speed only by throttle control to realize the smooth running of a car. SOLUTION: A control device obtains a difference between present car speed detected through a car speed sensor and target car speed decided according to the operation quantity of an accelerator, and drives a throttle motor (actuator) according to the above difference to control throttle opening. In the case where the throttle is opened more than the set opening, the target car speed is once set up to a target ceiling car speed V lower than a limit car speed Vmax (the maximum set car speed), and when the present car speed arrives at a medium car speed Vm which is set up the same as the target ceiling car speed or smaller than that value, the target car speed is gradually increased to the limit car speed Vmax . Thus, in the case where the accelerator is wholly opened to start the vehicle, since the target car speed is gradually increased to the limit car speed Vmax from the time when the present car speed arrives at the medium car speed Vs , the present car speed is also gradually increased to the limit car speed Vmax , and overshoot is thereby prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle control device for controlling a vehicle speed of a vehicle traveling by a driving force of an engine.

[0002]

2. Description of the Related Art For example, a golf car carrying luggage such as a golf bag or a person in a golf course automatically detects a guide line buried in a guide route and automatically runs along the guide line. It is possible to carry out a manual drive in which the vehicle is operated manually, and the vehicle speed is controlled by the throttle control device.

By the way, the throttle control device obtains a difference between a current vehicle speed detected by a vehicle speed sensor and a target vehicle speed determined according to an accelerator operation amount, and drives an actuator such as a motor according to the difference. This is a device for controlling the throttle opening of the engine.

[0004]

By the way, in the manual running of a golf car equipped with a throttle control device, when the occupant starts with the accelerator fully opened, the vehicle speed greatly exceeds the target vehicle speed, so-called overshoot. Can be large.

If the opening of the throttle is made slow with respect to the accelerator opening in order to solve the above problem, the responsiveness of the vehicle speed to the accelerator operation will be impaired.

If the brake control is performed in addition to the throttle control as another method, the reliability is lowered and the energy efficiency is deteriorated due to the complicated control, and smooth running of the vehicle is hindered. Problems such as occur.

The present invention has been made in view of the above problems, and an object of the present invention is to prevent overshoot of the vehicle speed only by the throttle control without causing deterioration of reliability and deterioration of energy efficiency. It is an object of the present invention to provide a throttle control device for a vehicle that can realize smooth running.

[0008]

In order to achieve the above object, the invention according to claim 1 obtains a difference between a current vehicle speed detected by a vehicle speed sensor and a target vehicle speed determined according to an accelerator operation amount, In a throttle control device for a vehicle that drives an actuator according to this difference to control the throttle opening, when the throttle is opened more than a set opening, the target vehicle speed is once set to a target striking speed lower than the maximum set vehicle speed. The target vehicle speed is set to the maximum set vehicle speed when the current vehicle speed reaches the intermediate vehicle speed set to a value equal to or smaller than the target striking vehicle speed.

The invention according to claim 2 is characterized in that, in the invention according to claim 1, when the current vehicle speed is reduced to the intermediate vehicle speed, the target vehicle speed is gradually reduced to the target heading vehicle speed.

Therefore, according to the first aspect of the invention, for example, when the vehicle is started with the accelerator fully opened, the target vehicle speed is once set to a target striking speed lower than the maximum set vehicle speed, and the current vehicle speed is an intermediate vehicle speed. Since the target vehicle speed is gradually increased to the maximum set vehicle speed after reaching the maximum value, the current vehicle speed is gradually increased to the maximum set vehicle speed and its overshoot is prevented.Thus, the throttle control can be performed without lowering reliability and energy efficiency. A smooth start of the vehicle can be realized only by this.

Further, according to the second aspect of the invention, when the current vehicle speed decreases to the intermediate vehicle speed while the vehicle is traveling uphill, for example, the target vehicle speed is gradually reduced to the target heading vehicle speed. After that, an overshoot of the vehicle speed when the vehicle travels on a horizontal road or a downhill is prevented.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

First, the overall structure of the automatic vehicle will be outlined with reference to FIG. Incidentally, FIG. 1 is a block diagram showing the structure of the automatic vehicle.

The automatic vehicle according to the present embodiment is used as a golf car used in, for example, a golf course, and can be automatically driven along a predetermined guide route or manually operated by an occupant. Is. This automatic vehicle is equipped with an engine 1, and a transmission 4 for transmitting a driving force supplied from the engine 1 via a V-belt type automatic transmission 2 to rear wheels 3a and 3b which are drive wheels. A steering wheel 5 for steering the front wheels 3c, 3d, which are steered wheels; an accelerator for adjusting the opening (throttle opening) of a throttle valve (not shown) provided in the carburetor 6 of the engine 1 for changing the vehicle speed. A pedal 7, a brake pedal 8 for applying a braking force to the vehicle, a drum brake 9, and a shift lever 10 for switching between forward and backward movement of the vehicle are provided.

The automatic vehicle is also equipped with a controller 11 for controlling automatic traveling, a steering driver 12, a steering motor 13, and a throttle motor 1.
4, brake motor driver 15, brake motor 1
6. In addition to the electromagnetic brake 18, guide wire sensors 19a, 19
b, 19c, fixed point sensor 20, left and right bumper switches 2
1, a collision prevention sensor 22, various sensor groups such as left and right obstacle sensors 23, a switching mechanism 24 for switching between automatic braking and manual braking, and a signal from the remote control transmitter 25 for receiving and inputting them to the controller 11. Remote control receiver 2
6 and the like are provided. In FIG. 1, 27 is an amplifier for the rear-end collision prevention sensor 22.

By the way, the steering driver 12
Supplies a drive current corresponding to a steering instruction signal output from the controller 11 to the steering motor 13 via a steering relay 28 during automatic traveling. The rotation of the steering motor 13 is driven by gears 29, 30.
A steering operation is transmitted to the steering shaft 31 via a steering wheel, and the steering shaft 31 rotates to perform a desired steering operation. During automatic driving, the controller 11
Steering clutch 32 is turned off by the signal from
Then, the steering wheel 5 is separated from the steering shaft 31, and manual steering operation becomes impossible.

The throttle motor 14 is driven in response to an opening degree instruction signal output from the controller 11 during automatic traveling to adjust the opening degree of the throttle valve in the carburetor 6 (throttle opening degree). During automatic driving, the throttle clutch 33 is turned on by the signal output from the controller 11 and the throttle motor 1
4, the throttle operation is performed, the throttle clutch 33 is turned off and the throttle pedal is operated by the accelerator pedal 7 during manual traveling. The operation amount (accelerator opening) of the accelerator pedal 7 is detected by the accelerator opening detection sensor 34, the throttle opening is detected by the throttle opening detection sensor 35, and the respective detection signals are input to the controller 11.

Further, the brake motor driver 15
Is to supply a drive current according to a control instruction signal output from the controller 11 to the brake motor 16 via the brake relay 36 during automatic traveling, and the brake motor 16 via the gear 37 and the switching mechanism 24. Then, the drum brake 9 provided on each of the four wheels 3a to 3d is driven to apply a braking force to the vehicle. Even during automatic traveling, the brake pedal 8 is connected to the drum brake 9 via the switching mechanism 24, and braking by operating the brake pedal 8 is also possible. The operation of the brake pedal 8 is detected by the brake switch 38,
The detection signal is input to the controller 11.

On the other hand, the guide wire sensors 19a to 19c
Is arranged at the center of the T-shaped arm 39 attached to the front end of the vehicle so as to be rotatable in the horizontal direction and to the left and right so as to face the ground. These guide wire sensors 19a to 19
c magnetically detects a guide wire (not shown) buried along the course of the golf course, and inputs a detection signal corresponding to the distance from the guide wire to the controller 11. Then, the controller 11 calculates the deviation amount of the vehicle position from the guide wire based on the detection signals from the guide wire sensors 19a to 19c, and outputs the steering instruction signal for setting the deviation amount to "0" to the steering driver 12 By outputting to, the vehicle is automatically driven along the guide line.

The fixed point sensor 20 is attached to a predetermined position of the vehicle so as to face the ground, and is composed of a plurality of fixed magnets (not shown) embedded in the golf course or the like at predetermined intervals. Is detected magnetically and a detection signal corresponding to the arrangement pattern is output to the controller 11, thereby providing the controller 11 with information for controlling the running / stopping of the vehicle and the traveling speed of the vehicle. is there.

By the way, an operation panel 40 is installed in the vicinity of the driver's seat, and in addition to the main switch, the operation panel 40 has a manual / automatic changeover switch for instructing switching between manual traveling and automatic traveling, starting and stopping. There are provided various switches such as a start / stop switch for instructing, and a warning lamp and an indicator lamp for displaying a warning. When automatic traveling is selected by the manual / automatic changeover switch of the operation panel 40, the controller 11 switches the traveling mode of the vehicle from manual traveling to automatic traveling and performs control for automatic traveling. In addition, as a sensor group for detecting the running state of the vehicle, two (No. 1 and 2) vehicle speed sensors 41, 42 for detecting the vehicle speed are provided for the transmission 4, and a rotation sensor 43 for detecting the number of revolutions for the engine 1. The gear 37 is provided with a brake limit switch 44 for detecting whether or not the rotation angle of the brake motor 16 exceeds a certain limit value because the stroke of the brake system including the drum brake 9 and the braking force transmission path becomes large. These detection signals are input to the controller 11.

Further, in the vicinity of the shift lever 10, a forward movement detection switch 45 and a reverse movement detection switch 46 for detecting the position of the shift lever 10 are provided, and an alarm buzzer 47 for issuing an alarm at the time of reverse movement is provided. Cage,
These are electrically connected to the controller 11.

Here, the configuration of the main part of the controller 11 (the part relating to the throttle control device according to the present invention) is shown in FIG.
It will be described based on. 2. FIG. 2 is a block diagram showing the configuration of the main part of the controller 11.

The controller 11 is composed of a CPU (central processing unit) 48 and hardware such as a memory. As shown in FIG. 2, the CPU 48 includes an accelerator opening detection sensor 34 and vehicle speed sensors 41, 42. And a detection signal detected by the throttle opening degree detection sensor 35, an opening degree detection sensor input section 49, a vehicle speed sensor input section 50,
Inputs are made via the opening degree detection sensor input units 51, respectively.

The CPU 48, as software, is based on the detection signals from the accelerator sensor calculation processing section 52 for calculating the accelerator opening based on the detection signal from the accelerator opening detection sensor 34 and the vehicle speed sensors 41 and 42. Vehicle speed calculation processing unit 53 for calculating the actual speed and acceleration of the vehicle, a throttle sensor calculation processing unit 54 for calculating the throttle opening based on the detection signal from the throttle opening detection sensor 35, the accelerator sensor calculation processing unit A target vehicle speed calculation processing section 55 and the vehicle speed calculation processing section for calculating a target vehicle speed of the vehicle on the basis of the accelerator opening calculated in 52 and the actual speed and acceleration of the vehicle calculated in the vehicle speed calculation processing section 53. The actual speed and acceleration of the vehicle obtained at 53 and the throttle sensor calculation processing unit 5 Throttle instruction processing unit 56 for obtaining the control amount of the throttle opening degree (throttle instruction amount) are incorporated and a throttle opening degree determined in.

Then, the throttle instruction calculation processing section 5
A control signal corresponding to the throttle control amount obtained in 6 is output from the throttle instruction calculation processing unit 56 to the throttle motor 14 via the throttle output unit 57, and the throttle motor 14 is driven to drive the engine 1
The throttle valve is opened and closed, the rotation speed of the engine 1 is adjusted, and the vehicle speed of the vehicle is controlled.

Here, the vehicle speed control by the conventional throttle control device will be explained based on the timing chart shown in FIG. 4 (a).

When the occupant depresses the accelerator pedal 7 to the throttle fully open position when starting, the throttle opening changes as shown in FIG. 4 (a), while the target vehicle speed is as shown in FIG. 4 (a). After abruptly rising to the maximum set vehicle speed (hereinafter referred to as the limit vehicle speed) V _max ,
Since the limit vehicle speed V _max is maintained, the current vehicle speed (actual vehicle speed) sharply increases with a slight time delay as shown in the figure with respect to the target vehicle speed, and eventually exceeds the limit vehicle speed V _max in the figure. Will overshoot like.

Further, after the throttle opening is fully closed during traveling, the target vehicle speed is rapidly raised to the limit vehicle speed V _max as shown in FIG. 4A because the accelerator pedal 7 is stepped on again. In this case, the current vehicle speed will overshoot again as shown.

The present invention is designed to eliminate the above-mentioned overshooting only by the throttle control (more specifically, the target vehicle speed control). Hereinafter, the operation of the throttle control device according to the present invention will be described with reference to FIG. This will be described based on the flowchart shown and the timing charts shown in FIGS. 4 and 5.

When the occupant depresses the accelerator pedal 7 to the throttle fully open position when starting, the throttle opening changes as shown in FIG. 4 (b), and the throttle opening starts to decrease at a timing ΔT earlier than before. To do.

In the target vehicle speed control, first,
The target striking vehicle speed V lower than the limit vehicle speed V _max and the accelerator vehicle speed (the vehicle speed that is determined with respect to the accelerator opening and is the same as the conventional target vehicle speed (see FIG. 4A)) are respectively calculated by the following equations. Required (STEP 1 in Figure 3).

[0033]

## EQU1 ## Target striking vehicle speed (V) = intermediate vehicle speed (V _m ) + constant α (1) accelerator vehicle speed = accelerator opening × speed conversion coefficient β (2) The intermediate vehicle speed V _m is determined by an experiment. The optimum value is obtained, and the target heading vehicle speed V is set higher than the intermediate vehicle speed V _m by a constant α (≧ 0). Further, the accelerator vehicle speed is obtained as shown in FIG. 4 (b) with respect to the accelerator opening, and like the conventional target vehicle speed (see FIG. 4 (a)), the vehicle speed is rapidly increased linearly to the limit vehicle speed V _max. After being given
The limit vehicle speed V _max is maintained.

Next, it is determined whether the current vehicle speed obtained by the current vehicle speed calculation processing unit 53 (see FIG. 2) of the CPU 48 is the intermediate vehicle speed V _m or more and the accelerator vehicle speed is the target striking speed V or more. Is judged (STEP 2 in FIG. 3),
In the initial stage of starting when the accelerator vehicle speed is lower than the target striking speed V, the determination result in STEP2 is "NO", so the process proceeds to STEP3, in which the target vehicle speed is higher than the target striking speed V, and It is determined whether the current vehicle speed is lower than the intermediate vehicle speed V _m and the accelerator vehicle speed is higher than the intermediate vehicle speed V _m .

At the initial stage of starting when the accelerator vehicle speed is lower than the intermediate vehicle speed V _m , the determination result in STEP3 is "NO", so the processing proceeds to STEP4, where the target vehicle speed is set to the accelerator vehicle speed, and this state is the target. It is maintained until the vehicle speed reaches the target heading vehicle speed V (STEP 5). The change over time of the target vehicle speed at this time is shown by a straight line a in FIG.

When the target vehicle speed reaches the target heading vehicle speed V, the determination result in STEP 5 is "YES",
As indicated by a straight line b in (b), the target vehicle speed is once set to the target heading vehicle speed V for a predetermined time (STEP 6).

By controlling the target vehicle speed as described above, the current vehicle speed increases as shown in FIG. 4 (b), and when the current vehicle speed eventually reaches the intermediate vehicle speed V _m , the determination result in STEP 2 is "YES". Therefore, the process proceeds to STEP 7, and whether the average acceleration α _{av of the} vehicle is “0” or more (α _av ≧ 0)
It is determined whether or not. Here, the average acceleration α _av is the current vehicle speed V _i (i =
The acceleration α _i (i = 1, 2, 5) obtained by differentiating 1, 2, 5) with time t is averaged and calculated.

[0038]

## EQU2 ## α _i = dV _i / dt (i = 1,2, -5) (3) α _av = Σα _i / 5 (4) Then, as shown in FIG. Since the vehicle speed is currently increasing, the average acceleration α _av ≧ 0 calculated by the above equation (4) becomes 0, and the judgment result in STEP 7 is “Y
ES ”, the process proceeds to STEP8, where the target vehicle speed is increased by V ₀ to the accelerator vehicle speed (limit vehicle speed V _max ). Therefore, as shown by the straight line c in FIG. _{When the} vehicle speed reaches _m , the target vehicle speed changes from the target heading vehicle speed V to the accelerator vehicle speed (the limit vehicle speed V
_max ) and the target vehicle speed reaches the accelerator vehicle speed (limit vehicle speed V _max ), as shown by the straight line d in FIG.
_max ) is set.

As described above, when the vehicle is started with the accelerator fully opened, the target vehicle speed is once set to the target heading vehicle speed V lower than the limit vehicle speed V _max , and the current vehicle speed reaches the intermediate vehicle speed V _m. Since the target vehicle speed is gradually increased to the accelerator vehicle speed (limit vehicle speed V _max ) from, the current vehicle speed is also the accelerator vehicle speed (limit vehicle speed V _max ) as shown in FIG. 4B.
Is gradually increased to prevent overshoot. And
In the present embodiment, the overshoot of the current vehicle speed can be prevented only by the throttle control (target vehicle speed control), so that a smooth start of the vehicle can be realized without lowering the reliability or the energy efficiency. You can

Next, when the occupant releases the accelerator pedal 7 and the throttle is fully closed while the vehicle is traveling at the accelerator vehicle speed (limit vehicle speed V _max ), the target vehicle speed is linear as shown in FIG. 4 (b). As indicated by e, the vehicle speed decreases with the accelerator vehicle speed (STEP 10), and the current vehicle speed also decreases accordingly. After that, when the occupant depresses the accelerator pedal 7 to the throttle fully open position, the STEP is performed in the same manner as when starting.
The judgment results of 2 and 3 are both “NO”, and the target vehicle speed is set to the accelerator vehicle speed (STEP 4).
Up to the point abruptly along the straight line f in FIG. 4 (b) (STEP 5).

If the accelerator vehicle speed reaches the target heading vehicle speed V while the current vehicle speed has not dropped to the intermediate vehicle speed V _m , the result of the determination in STEP 2 is "YES", so the process proceeds to STEP 7. move on. At this time, the vehicle is decelerating, and the current vehicle speed is decreasing as shown in FIG. 4 (b), so the average acceleration α _av <0 of the vehicle, and therefore the result of the determination in STEP 7 is “NO”. next, the process proceeds to STEP7, the target vehicle speed is larger V ₁ (> V ₀₎ by being up than V _0. Then, the current vehicle speed changes from deceleration to acceleration, and the average acceleration α _av ≧ 0. Therefore, the determination result in STEP 7 is “YE
S ”, and thereafter, the target vehicle speed is increased by a value V ₀ (<V ₁ ) smaller than V ₁ until the target vehicle speed reaches the accelerator vehicle speed (limit vehicle speed V _max ) (STEP 8).

That is, after the target vehicle speed reaches the target heading vehicle speed V, the target vehicle speed is as shown in FIG. 4 (b) until the current vehicle speed changes from deceleration to acceleration and the average acceleration α _av ≧ 0 of the vehicle. Straight line g
Since it is gradually increased relatively rapidly along with, the accelerator response at the re-acceleration is enhanced, and thereafter, the straight line h of FIG.
As the current vehicle speed increases relatively slowly along with, the overshoot of the current vehicle speed at the time of re-acceleration can be prevented.

When the target vehicle speed reaches the accelerator vehicle speed (limit vehicle speed V _max ), the determination result in STEP 9 is "Y".
As shown by the straight line i in FIG. 4B, the target vehicle speed is set to the accelerator vehicle speed (limit vehicle speed V _max ) (STEP 10), and the vehicle travels at the accelerator vehicle speed (limit vehicle speed V _max ). To do.

Next, after the vehicle has started and the current vehicle speed has reached the accelerator vehicle speed (limit vehicle speed V _max ), for example, 10 °
Throttle control when traveling on the slope having the above gradient will be described based on a timing chart shown in FIG.

When the current vehicle speed reaches the accelerator vehicle speed (limit vehicle speed V _max ) after the vehicle has started, the target vehicle speed is set to the accelerator vehicle speed (limit vehicle speed V _max ) (see FIG. 3).
If the current vehicle speed gradually decreases as shown in FIG. 5 due to the vehicle traveling uphill, and eventually decreases to the target vehicle speed, the determination result in STEP 3 of FIG. 3 is “YES”.
Therefore, the processing proceeds to STEPs 12 and 13, and the target vehicle speed is gradually decreased from the accelerator vehicle speed (limit vehicle speed V _max ) to the target heading vehicle speed V by V ₀ .

That is, when the vehicle travels uphill after starting, the target vehicle speed becomes the accelerator vehicle speed (limit vehicle speed V _max ) until the current vehicle speed reaches the intermediate vehicle speed V _m as shown by the straight line j in FIG. The target vehicle speed is set after that and is shown in Fig. 5.
Is gradually reduced along the straight line k. In the present embodiment,
Although both the target vehicle speed increase ratio in STEP 8 and the target vehicle speed increase ratio in STEP 12 are set to V ₀ , it goes without saying that they may be set to different values.

When the target vehicle speed drops to the target heading vehicle speed V, the target vehicle speed is set to the target heading vehicle speed V (STEP
14) After that, the state is maintained (see the straight line m in FIG. 5).

As described above, according to the present embodiment, when the current vehicle speed decreases to the intermediate vehicle speed V _m while the vehicle is traveling on the slope, the target vehicle speed is gradually reduced to the intermediate vehicle speed V _m. Therefore, after that, the vehicle speed overshoot is prevented when the vehicle travels on a horizontal road or a downhill.

In the present embodiment, the case where the present invention is applied to an automatic traveling vehicle such as a golf car has been described. However, the present invention is applicable to any vehicle that is driven by the driving force of the engine. .

[0050]

As is apparent from the above description, claim 1
According to the invention described above, for example, when the vehicle is started with the accelerator fully opened, the target vehicle speed is once set to a target heading vehicle speed lower than the maximum set vehicle speed, and the target vehicle speed is set from the time when the current vehicle speed reaches the intermediate vehicle speed. Since it is gradually increased to the maximum set vehicle speed,
The current vehicle speed is also gradually increased to the maximum set vehicle speed to prevent its overshoot, and it is possible to achieve a smooth start of the vehicle only by throttle control without lowering reliability and energy efficiency. To be

Further, according to the second aspect of the invention, when the current vehicle speed decreases to the intermediate vehicle speed while the vehicle is traveling uphill, for example, the target vehicle speed is gradually reduced to the target heading vehicle speed. After that, the effect of preventing overshoot of the vehicle speed when the vehicle travels on a horizontal road or a downhill is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an automatic vehicle equipped with a throttle control device according to the present invention.

FIG. 2 is a block diagram showing a configuration of a controller of an automatic vehicle equipped with a throttle control device according to the present invention.

FIG. 3 is a flowchart for explaining the operation (target vehicle speed control) of the throttle control device according to the present invention.

FIG. 4A is a diagram showing changes in various speeds in vehicle speed control by a conventional throttle control device, and FIG. 4B is a change in various speeds in vehicle speed control by the throttle control device according to the present invention (deceleration after starting). FIG. 3 is a diagram showing a case of performing re-acceleration).

FIG. 5 shows various speed changes in vehicle speed control by the throttle control device according to the present invention (when traveling uphill after starting).
FIG.

[Explanation of symbols]

 7 accelerator pedal 11 controller 14 throttle motor (actuator) 34 accelerator opening detection sensor 35 throttle opening detection sensor 41, 42 vehicle speed sensor

Claims (2)

[Claims] 1. A throttle of a vehicle for determining a difference between a current vehicle speed detected by a vehicle speed sensor and a target vehicle speed determined according to an accelerator operation amount, and driving an actuator according to the difference to control a throttle opening degree. In the control device, when the throttle is opened more than the set opening, the target vehicle speed is once set to a target striking speed lower than the maximum set vehicle speed,
A throttle control device for a vehicle, wherein the target vehicle speed is gradually increased to a maximum set vehicle speed when the current vehicle speed reaches an intermediate vehicle speed set to a value equal to or smaller than the target heading vehicle speed. 2. The throttle control device for a vehicle according to claim 1, wherein the target vehicle speed is gradually reduced to the target heading vehicle speed when the current vehicle speed is reduced to the intermediate vehicle speed.