JPS6116137A - Vehicle travel control device - Google Patents

Abstract

PURPOSE:To enhance the safety of a travel control device, by releasing the follow-up travel of a vehicle under control of a travelling vehicle follow-up control means when an undesirable surrounding detecting means detects undesirable surroudings. CONSTITUTION:An undesirable surrounding detecting means (a) detects undesirable surroundings or weather conditions such as, rain, fog, snow, etc. which incurr the lowering of performance of an optical radar (b) for measuring the vehicle-to-vehicle distance with respect to the preceding vehicle. A safety vehicle- to-vehicle distance computing means (d) computes the safety vehicle-to-vehicle distance between the instant vehicle and the preceding vehicle in accordance with a vehicle speed measured by a vehicle speed measuring means (c). A preceding vehicle follow-up control means (e) delivers, to a vehicle power system (g), a control signal which sets the vehicle-to-vehicle distance to a distance longer than the safety vehicle-to-vehicle distance calculated by the safety vehicle-to- vehicle distance. A releasing means (f) releases the follow-up travel of the instant vehicle when the undesirable surroundings detecting means (a) detects undesirable surroundings.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is a vehicle travel control device that uses optical radar to maintain a safe distance from a preceding vehicle to maintain optimal driving conditions. Regarding improvements.

(Prior art and its problems) Conventional vehicle travel control devices using optical radar include:
For example, there is one described in JP-A-58-139214.

By the way, optical radar equipment generally uses rain+ff.

Performance deteriorates under weather conditions such as snow. Therefore, in a vehicle travel control device equipped with such an optical radar device, under weather conditions such as rain, frost, snow, etc.,
There was a risk that it would not be possible to accurately measure the distance between the host vehicle and the preceding vehicle.

(Objective of the Invention) The object of the present invention is to improve the safety of this type of vehicle travel control device in J5 when the performance of the optical radar mounted on the float deteriorates due to deterioration of the surrounding environment. be.

(Structure of the invention) The basic structure of the present invention is shown in the claim correspondence diagram of FIG.

In the figure, the bad environment detection means a detects that the current weather environment during the vehicle is in a bad environment such as rain, fog, snow, etc., which degrades the performance of the optical radar.

Optical radar b measures the inter-vehicle distance to a preceding vehicle existing within a predetermined warning area in front of the own vehicle.

The vehicle speed measurement means C detects the speed of the own vehicle while the vehicle is running, and the safe inter-vehicle distance calculation means d calculates the safe inter-vehicle distance from the preceding vehicle based on the own vehicle speed measured by the vehicle speed measurement means C.

The preceding vehicle following driving control means e is configured to adjust the distance between the preceding vehicle and the preceding vehicle measured by the optical radar b to a safe distance determined by the safe following distance calculating means d based on the own vehicle speed measured by the vehicle speed measuring means C. A control signal is output to the vehicle power system g to control the own vehicle speed so that the vehicle speed is equal to or greater than the distance.

Furthermore, when the adverse environment detecting means a detects an adverse environment, the canceling means f cancels the following driving by the preceding vehicle following driving controlling means e.

(Description of an Embodiment) Next, FIG. 2 shows the configuration of an embodiment of a vehicle running control device according to the present invention. In the figure, an optical radar device 30 transmits a pulsed laser beam L (D) to a warning area in front of the host vehicle, receives reflected light L (R) from the preceding vehicle, and receives its propagation delay time τ. Delay time data Dτ indicating the distance between the vehicle and the vehicle in front is output.

Further, 32 is a vehicle speed sensor that detects the own vehicle speed, and the vehicle speed sensor 32 can be configured, for example, by rotating a magnet using rotational force obtained from a speedometer cable of the vehicle, and by bringing a reed switch close to this magnet to generate a pulse train. This pulse train signal is output as F/V'! A J converter is used that converts the voltage into an analog voltage proportional to the vehicle speed.

The detection output of the vehicle speed sensor 32 is converted into a digital signal by the A/D converter 34 and output to the microcomputer 4G.

36 is a wiper switch, which detects whether the wiper is in continuous operation, intermittent operation, or non-operation, and sends the detection output to microcomputer 40. Output.

38 is a vehicle speed setting switch for setting the vehicle speed of the own vehicle to a desired vehicle speed, and for example, a numeric keypad or the like is used.

In addition to using the numeric keypad as described above, the desired vehicle speed can be set by storing the current vehicle speed as the set vehicle speed based on the output signal from the vehicle speed setting switch 38, or by outputting it from the vehicle speed setting switch 3. There is a method in which a predetermined speed counter is incremented based on a signal and the counted data at an arbitrary point in time is stored as a set vehicle speed.

The microcomputer 40 includes the optical radar device 30, A/
D converter 34. The outputs of the wiper switch 36 and the vehicle speed setting switch 38 are taken in, the processes shown in FIGS. 4 to 6 are performed based on these output signals, and the control signals for controlling the vehicle in the optimum driving state are converted to D/A. It outputs a display control signal to the converter 42 and to the display device 52 for displaying the inter-vehicle distance and the like.

The D/A converter 42 converts the control signal from the microcomputer 40 into an analog signal, and converts the control signal from the microcomputer 40 into an analog signal.
Output to.

The servo control circuit 44 includes an analog output of the D/A converter 42 and a detection node J of the throttle potentiometer 50 that detects the opening degree of the throttle valve 51 in the engine 48.
A drive signal corresponding to these deviations is output to the step motor 46.

A step motor 46 whose rotating shaft is connected to the throttle valve 51 adjusts the throttle valve 51 to a predetermined opening degree in response to a drive signal from the servo control circuit 44, and the vehicle is controlled to the @''m operating state according to the driving environment. be done.

Next, the contents of the program executed by the microcomputer 40 will be explained with reference to FIGS. 3 to 5.

FIG. 3 shows the contents of the main routine, and this main routine controls the vehicle following the preceding vehicle based on the vehicle travel control details specified in the interrupt routine shown in FIG. 4 or 5. Alternatively, a series of processes are performed to perform constant speed driving control.

In Figure 3, when the program is started, step (
In step 100), it is determined whether the preceding vehicle following flag has been set. Here, the preceding vehicle following driving flag is a flag for instructing preceding vehicle following driving control.

If it is determined in step (100) that the preceding vehicle following flag is in the reset state, step (105) is performed.
to move to. Further, if it is determined in step (100) that the preceding vehicle following flag is set, in step (101) the distance between the vehicle and the preceding vehicle is determined based on the delay time data Dτ output by the optical radar device 30. distance,
is measured.

Next, in step (102>) the vehicle speed sensor 32 outputs A/
The own vehicle speed is read through the D converter 34, and step (1)
03), a safe inter-vehicle distance 1ift L2 is calculated based on the own vehicle speed detected by the vehicle speed sensor 32.

Then, in step (104), step (101)
The distance between the vehicle and the preceding vehicle determined by 1311+ and the step (
A correction output (control signal) corresponding to the deviation ΔL of the safe inter-vehicle distance L2 determined in step 103) is output to the D/A converter 42.

Furthermore, in step (105>), it is determined whether the constant speed running flag is set.

Here, the constant speed running flag is a flag for instructing constant speed running control. If it is determined in step (105) that the constant speed running flag is in the reset state, execution of the main routine is terminated, and on the other hand, if it is determined that the constant speed running flag is set, step (105) is performed. 106)
In step (106), the own vehicle speed v1 is read from the lX speed sensor 32 via the A/D converter 34, and in the next step (108), the set output of the vehicle speed setting switch 38, that is, the set vehicle speed is read. v2 is loaded.

Then, in step (110), own vehicle speed 1 and set vehicle speed v2
A correction output (control signal) corresponding to the deviation ΔV is output to the D/A converter 42, and the execution of this main routine ends.

Next, FIG. 4 shows the contents of the vehicle speed setting interrupt routine. This routine is started by operating the vehicle speed setting switch 38.

In the figure, when the vehicle speed setting interrupt routine is started,
In step (200), the own vehicle speed is read from the vehicle speed sensor 32, and in the next step (201), the vehicle speed setting switch 38 is read.
The vehicle speed is set using the numeric keypad etc. that make up the system, and a constant speed running flag is set at step (200).
Then, in the next step (203), the manual setting flag is set, and the execution of this interrupt routine is ended.

Here, the manual setting flag set in step (203) is a flag that allows constant speed driving control to be performed regardless of the driving environment when the vehicle speed is manually set.

Next, FIG. 5 shows the contents of the bad environment detection interrupt routine.

This interrupt routine is activated at regular intervals by a timer interrupt. In the figure, when this interrupt routine is started, it is determined in step (300) whether or not the manual setting flag is set, and if the manual setting flag is set, no processing is performed. Execution of this interrupt routine is terminated.

On the other hand, if it is determined in step (300) that the manual setting flag is in the reset state, step (301)
In step 302, the detection output of the wiper switch 36 is read, and in the next step (302>), it is determined whether the wiper switch 36 is in the operating state.

If it is determined in step (302> that the wiper switch is in the operating state), it is determined in step (303) whether or not the wiper is in the intermittent operating state, and it is determined that the wiper is in the continuous operating state. If so, the process further advances to step (304), where it is determined whether or not the wiper has been in continuous operation for a predetermined period of time or longer.

If it is determined in step (3,04) that the wiper continuous operation state has continued for a certain period of time or more, it is determined that the driving environment is bad, and in the next step (305), the preceding vehicle following driving flag is set. A determination is made as to whether or not it is set. If it is determined in step (305) that the preceding vehicle following flag is set, step (305)
In step 306), the preceding vehicle following driving flag is reset, in the next step (307), a constant speed driving flag is set, and in step (308), the current vehicle speed is set from the vehicle speed sensor 32, and this interrupt routine is executed. end.

How to use: If it is determined in step (303) that the wiper is in an intermittent operating state, or in step (304')
If it is determined in step (305) that the wiper continuous operation state has not continued for a certain period of time or more, and furthermore, if it is determined in step (305) that the preceding vehicle following flag is in the reset state, this interrupt routine continues. Terminates execution. This is because in these cases, the performance of the optical radar device 30 is fully demonstrated.

Furthermore, if it is determined in step <302) that the wiper switch 36 is in the inactive state, step (309
), and in step (309) it is determined whether the constant speed running flag is set. Here, if it is determined that the constant speed running flag is in the reset state,
Execution of this interrupt routine is then terminated.

How to use: If it is determined in step (309) that the constant speed driving flag is set, the preceding vehicle following driving flag is set in step (310), and the next step (31
In step 1), the constant speed running flag is reset and the execution of this interrupt routine is ended.

In this way, in this interrupt routine, wiper switch 3
It is determined whether the driving environment is a bad environment based on the operating state of 6, and if it is not a bad environment, it instructs constant speed driving control, and if the R environment is detected, it cancels the preceding vehicle following driving control. Then, the system instructs the driver to shift to constant speed driving control.

As explained above, in this embodiment, when the performance of the optical radar device installed in the vehicle decreases due to an adverse environment while the vehicle is running under the preceding vehicle following control, the preceding vehicle following control is performed. Since the system is configured to be released, it is possible to automatically avoid abnormally approaching or rear-ending a vehicle in front.

In this embodiment, the wiper switch 36 that detects the operating state of the wiper is used as the bad environment detection means a, but the present invention is not limited to this, and examples include a wet senna that detects the humidity of the outside air, and an outside air temperature. A sensor or a solar radiation sensor for detecting a solar radiation state may be combined with a wiper switch, and a bad environment may be detected using a signal obtained by calculating the logical sum of the detection outputs of these sensors.

(Effects of the Invention) According to the present invention, while the vehicle is traveling using the preceding vehicle following travel control means, the current weather environment becomes a bad environment such as rain, fog, snow, etc. that causes a decline in the performance of the optical radar. In the case of
The safety of this type of device can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of the present invention, FIG. 2 is a block diagram showing the configuration of an embodiment of the vehicle travel control device according to the present invention, and FIGS. 3 to 5 are block diagrams showing the configuration of the microcomputer 40. Indicates the contents of the program executed by
Figure 3 is a flowchart showing the contents of the main routine.
FIG. 4 is a flowchart showing the contents of the vehicle speed setting interruption routine, and FIG. 5 is a flowchart showing the contents of the bad environment detection interruption routine. a...Bad environment detection means b...Optical radar C...Vehicle speed measurement means d...Safe inter-vehicle distance calculation means e...Advance Vehicle following travel control means f...
Release means 30... Optical radar device 32... Vehicle speed sensor 36... Wiper switch 38... Vehicle speed setting switch 40... Microcomputer 50... Throttle potentiometer 52... Display device

Claims (1)

[Claims] (1) The distance between the vehicle in front and the vehicle in front as measured by optical radar is
Vehicle travel control comprising a preceding vehicle following travel control means for controlling the own vehicle speed by operating the vehicle power system so that the vehicle speed is equal to or greater than the safe inter-vehicle distance calculated based on the own vehicle speed measured by the vehicle speed measuring means. In the device; an adverse environment detecting means for detecting that the current weather environment is an adverse environment such as rain, fog, snow, etc.; 1. A vehicular travel control device comprising: a canceling means for canceling the following driving by the preceding vehicle following driving controlling means when an adverse environment is detected.