JPH02179550A - Traveling controller for vehicle - Google Patents

Abstract

PURPOSE:To facilitate the drive on a stagnant road by reading out the previously memorized pseudo acceleration value according to the between-vehicle distance and the car speed detected by a car speed sensor and carrying out the throttle valve control or automatic brake control, when the stagnant road traveling state is detected. CONSTITUTION:During the operation of a vehicle, a controller 20 judges if the vehicle is in the stagnant road traveling mode or not, from the output signals of an engine revolution speed sensor 1, lever position detecting switch 2, parking brake switch 3, exhaust brake switch 4, accelerator pedal switch 5, and a between-vehicle distance sensor 6. If the judgement is 'YES', it is checked if the between-vehicle distance detected by the sensor 6 is 2m or less or not, and if the judgement is 'NO$', it is judged if the between-vehicle distance becomes stagnant or not, from the variation rate of the between-vehicle distance. The pseudo acceleration variable is obtained from a map on the basis of the between-vehicle distance and car speed, and a throttle valve 8 or exhaust brake valve 9 is operated according to the value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vehicle travel control device, and more particularly to a device for controlling the travel of a fully automatic transmission-equipped vehicle on a congested road.

(Prior technology) Vehicles with electronically controlled clutch type automatic transmission (hereinafter referred to as A/T
When driving on a congested road, the accelerator pedal and the brake pedal are operated appropriately with the foot in an A/T vehicle equipped with a torque converter or an A/T vehicle equipped with a torque converter.

In addition, manually operated transmission vehicles (hereinafter referred to as M/T vehicles)
In this case, the operation of the clutch pedal is added to the accelerator pedal and brake pedal.

Therefore, compared to M/T cars, A/T cars do not require clutch pedal operation and are easier to drive on congested roads, but because the accelerator and brake pedals still need to be operated, driving on long congested roads, etc. Driver fatigue increases.

In consideration of these points, when the distance between the vehicle in front of the vehicle and the vehicle ahead becomes closer than the braking distance according to the current vehicle speed, the brakes are automatically applied to maintain a constant distance between the vehicle and the vehicle in front. Japanese Utility Model Application No. 58-181654 proposes a device that returns to normal auto-cruise driving when the vehicle accelerates and the distance between the vehicles increases.

[Problem to be solved by the invention]

However, in order to apply such a conventional vehicle cruise control device to a congested road, it is necessary to change the vehicle speed setting to a low vehicle speed. Then, unless the set value is changed, the vehicle speed cannot be increased above the set vehicle speed, which causes the problem that the inter-vehicle distance increases and causes traffic congestion.

Therefore, an object of the present invention is to enable a desired vehicle speed to be obtained even when driving on a congested road.

(Means for Solving the Problems) In order to achieve the above object, the vehicle travel control device according to the present invention includes an engine rotation speed sensor, a lever position detection switch, a parking brake inch, and an accelerator pedal switch. , an inter-vehicle distance sensor, a brake driving means, and when a congested road driving condition is detected by the outputs of at least these sensors and a switch, a pre-stored pseudo accelerator value is read out according to the inter-vehicle distance and the vehicle speed from the vehicle speed sensor, and the throttle is adjusted. It includes a controller that controls the valve and the brake drive means.

[For production]

In the present invention, the controller determines that the vehicle is traveling on a congested road based on output signals from at least an engine speed sensor, a lever position detection switch, a parking brake switch, an accelerator pedal switch, and an inter-vehicle distance sensor. When this occurs, a pre-stored pseudo accelerator value is calculated based on the inter-vehicle distance measured by the inter-vehicle distance sensor and the vehicle speed measured by the vehicle speed sensor, and when this pseudo accelerator value requests accelerator, the throttle valve is controlled according to the requested value. When the pseudo accelerator value is such that no accelerator request is made, the brake driving means is controlled to automatically operate the brake.

〔Example〕

FIG. 1 shows an embodiment of a vehicle running control device according to the present invention, in which 1 is an engine rotation speed sensor that detects the engine rotation speed from the position of the crankshaft, etc., and 2 is an A
/Lever position detection switch for detecting the position of the select lever for a T car; 3 is a parking brake inch that detects whether the parking brake lever is operating; 4 is a parking brake inch that detects whether the exhaust brake is operating or not. 5 is an accelerator pedal switch that detects whether or not the accelerator pedal is depressed;
6 is an inter-vehicle distance sensor that detects the distance to the vehicle in front; 7
1 is a vehicle speed sensor that detects the vehicle speed based on the rotation speed of the propeller shaft, 8 is a throttle valve that adjusts the amount of intake air to the engine, 9 is an exhaust brake valve that applies the brake by opening and closing the engine exhaust pipe, and 10 is a A brake pedal actuator 20 is for automatically operating the brake pedal, and 20 inputs the output signals from the sensors 1, 6.7 and switches 2 to 5 through the I10 interface, converts them into digital signals, and stores them in the ROM- R.A.
This is a controller that performs calculations using the memory of M and CPLJ and controls the throttle valve 8, exhaust brake valve 9, and brake pedal actuator IO via the I10 interface.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG.

First, the controller 20 receives the engine speed from the engine speed sensor l, the lever position from the lever position detection switch 2, the parking brake state from the parking brake switch 3, the exhaust brake state from the exhaust brake switch 4, and the accelerator pedal switch 5. The accelerator pedal state, the inter-vehicle distance from the inter-vehicle distance sensor 6, and the vehicle speed from the vehicle speed sensor 7 are each read (step SO).

Then, the controller 20 determines whether the vehicle is currently in the congested road driving mode based on the outputs of the sensors 1 and 6 and the switches 2 to 5.

This congested road driving mode means that all of the following six conditions (five conditions if the exhaust brake is not used) are satisfied.

01722 It is determined from the output of the rotation speed sensor 1 that the engine is rotating (step Sl).

■It is determined from the output of the lever position detection switch 2 that the position of the select lever is set to the fixed range of 2nd gear (step S2). There is no need to limit it.

■It is determined that the parking brake is pulled from the output of the parking brake switch 3 (step S
3) This is to prevent the vehicle from entering congested road driving mode while the parking brake is still applied.

(2) It is determined from the output of the exhaust brake switch 4 that the exhaust brake is operating (step S4). This is because the exhaust brake must be operated when stopping in the congested road driving mode. However, this condition is not particularly necessary for passenger cars that do not use exhaust brakes.

■It is determined from the output of the accelerator pedal switch 5 that the accelerator pedal is not depressed (step S5);
This is to give priority to the accelerator operation when the driver operates the accelerator even when the vehicle enters the congested road driving mode.

■It is determined from the output of the inter-vehicle distance sensor 6 that the inter-vehicle distance to the preceding vehicle is within a certain distance I1M (for example, 10 m) (steer knob S6), which means that the preceding vehicle has not suddenly turned. (This is to prevent them from running when the situation arises.

If these conditions are met, the subroutine for the congested road driving mode (step 37) is executed, and if even one of these conditions is missing, the normal driving mode (step 38) is executed.
) to the subroutine.

FIG. 3 is a flowchart showing the subroutine of the congested road driving mode (step 37) of FIG. 2.

First, in FIG. 3, the controller 20 checks whether the inter-vehicle distance output from the inter-vehicle distance sensor 6 is less than 2 m (step 371).

In this case, 2 m is an example of a distance that requires braking.

When the inter-vehicle distance is 2 m or more, it is determined whether the inter-vehicle distance is getting closer or not based on the rate of change in the inter-vehicle distance (step 372).

Then, when the rate of change in the inter-vehicle distance is positive and the inter-vehicle distance is increasing, a pseudo accelerator variable ACCEL is calculated from a predetermined map according to the inter-vehicle distance and vehicle speed at that time,
Or, when the rate of change is negative and the distance between vehicles is getting closer,
Find the pseudo accelerator variable ACCEL (step 57)
3).

In this pseudo accelerator change ACCEL ■ or ■,
The shorter the distance between vehicles and the higher the vehicle speed, the faster the brake control must be entered, so the value of ACCEL is set to "0".
Also, when the distance between vehicles is getting closer, the speed is faster (brake control has to be started, so the range of ACCEL-0 is larger. Also, when the distance is getting farther away, the ACCEL value is set so that the tracking speed is faster). ■ is a larger value than the ACCEL value ■, and conversely, the ACCEL value ■ of the one that is closer is a smaller value.

Note that when the rate of change in the inter-vehicle distance is found to be approximately "0", the previous ACCEL value is held (step 374).

l obtained in this way! Detective accelerator variable ACCEL■
Or, it is checked whether or not (2) is "θ" (step 375), and when it becomes ACCEL-0, it immediately shifts to brake control (step 376).

Various methods can be considered for this brake control; for example, ■ Activate the exhaust brake by energizing the exhaust brake valve (not shown) (the brake condition is satisfied even if the exhaust brake inch is turned on). (The brake operation will not be performed until the engine stops), or (2) forcibly stepping on the brake using an actuator such as an engine stop motoroid.

When the ACCEL value is not ``01'', the opening/closing control of the throttle valve is performed (step 577).

That is, the opening degree control of the throttle valve (not shown) is determined not by the actual depression amount of the accelerator pedal, but by the pseudo accelerator variable ACCEL, and the corresponding fuel injection control is performed.

That is, in the normal driving mode shown in step S8 in FIG. 2, the amount of accelerator depression by the human foot AD j A
CCEL and pseudo accelerator change ACCEL have a relationship as shown in the graph shown in Fig. 4, but in congested road driving mode, the actual accelerator depression amount is 'Os, so the third
The variables ACCEL (2) and (2) in the figure are generated in accordance with the parameters of inter-vehicle distance and vehicle speed.

When the inter-vehicle distance is determined to be less than 2 m in step 371, it is further checked whether the inter-vehicle distance is less than 1 m (step 37B).

If the inter-vehicle distance is less than 1 m, brake control is performed unconditionally (step 374), and if the inter-vehicle distance is In or more, the process returns to the flowchart of FIG. 2.

In addition, the two following distances, 2 m and 1 m, were used for determining the following distance as described above: one of the following distances (1 m in this example) was used.
When switching between accelerator control and brake control at the boundary, there is a possibility of chattering between the two controls.To prevent this, hysteresis is provided in the inter-vehicle distance between aborting accelerator control and entering brake control. .

In the above embodiment, the condition of a congested road is that the select lever position is in the fixed range of 2nd speed, but this condition and the condition of step S6 in FIG. If applied even in ranges), it will be possible to drive on expressways, etc., without operating the accelerator or brakes.

In addition, when it is difficult to reverse the vehicle into a garage, it is possible to do so by installing an inter-vehicle distance sensor at the rear and setting the select lever to R (reverse).

〔Effect of the invention〕

As described above, in the vehicle travel control device according to the present invention,
When driving on a congested road is detected, a pre-stored pseudo accelerator value is read out according to the inter-vehicle distance and the vehicle speed from the vehicle speed sensor, and throttle valve control or automatic brake control is performed, so the driver can control the steering wheel. Just by holding it in your hand, you can drive on congested roads.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of a vehicle travel control device according to the present invention, FIG. 2 is a flowchart diagram for explaining the operation of the embodiment of the present invention, and FIG. FIG. 2 is a flowchart showing the subroutine of the congested road driving mode, and FIG. 4 is a graph showing the relationship between the actual accelerator depression amount and the pseudo accelerator value. In Fig. 1, l is an engine speed sensor, 2 is a lever position detection switch, 3 is a parking brake inch, 4 is an exhaust brake switch, 5 is an accelerator pedal switch, 6 is an inter-vehicle distance sensor, 7 is a vehicle speed sensor, 8 9 represents a throttle valve, 9 represents an exhaust brake valve, 10 represents a brake pedal actuator, and 20 represents a controller, respectively. In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] Engine speed sensor, lever position detection switch,
A parking brake switch, an accelerator pedal switch, an inter-vehicle distance sensor, a brake drive means, and at least the outputs of these sensors and switches to detect a congested road driving condition in advance according to the inter-vehicle distance and the vehicle speed from the vehicle speed sensor. 1. A vehicle running control device comprising: a controller that reads out a stored pseudo accelerator value and controls a throttle valve and the brake driving means.