JPH06191361A - Inter-vehicle distance warning system - Google Patents

Abstract

(57) [Summary] [Structure] The information processing section 5 calculates a reference safe inter-vehicle distance from the inter-vehicle distance detected by the laser radar 1 and the vehicle speed sensor 2 and the own vehicle speed, and is detected by the light switch 3 and the wiper switch 4. The safe inter-vehicle distance is corrected according to the operating status of the lights and wipers. When the current inter-vehicle distance is shorter than the safe inter-vehicle distance, the alarm generator 6 gives an alarm to the driver. [Effect] In the inter-vehicle distance warning device, when rain or snow is falling and the road surface is slippery without using a special sensor, the inter-vehicle distance threshold value is corrected to be long to avoid a rear-end collision accident, and the visibility is dark. It is determined to be bad, and the threshold value of the inter-vehicle distance can be corrected to be longer to avoid the rear-end collision, and the safety can be further improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-vehicle distance warning system in consideration of driving conditions.

[0002]

2. Description of the Related Art Conventionally, in a vehicle safety alarm device as disclosed in, for example, Japanese Patent Application Laid-Open No. 2-258448, the distance between the vehicle and the surrounding vehicle is measured using ultrasonic waves and laser light.
When the distance becomes smaller than a certain threshold value, a warning is given to the driver.

[0003]

In the above-mentioned prior art, no consideration is given to driving conditions such as brightness and weather. For example, "when the distance is dark and the visibility is poor, the inter-vehicle distance should be long. "Because it's slippery on rainy or snowy days,
Increase the distance between cars. There is a problem that it is not realistic and cannot be said to be an inter-vehicle distance warning system that can respond to a driver's daily driving operation.

In order to solve such a problem, an object of the present invention is to provide a warning system capable of taking into consideration driving situations such as brightness and weather without using a special sensor. is there.

[0005]

In order to achieve this object, the present invention provides a means for detecting an inter-vehicle distance to a surrounding vehicle that changes from moment to moment, a means for detecting a speed of a vehicle, and the inter-vehicle distance. The vehicle-to-vehicle distance detected by the detecting means is obtained from the speed of the vehicle detected by the vehicle-speed detecting means and the time-dependent change in the vehicle-to-vehicle distance between the vehicle and the surrounding vehicles detected by the vehicle-interval distance detecting means. If the warning system has a means for giving a warning to the driver when it is shorter than the threshold value of the safe inter-vehicle distance set by the relative speed, it has a means for detecting wind wiper operation information or a means for detecting headlight lighting information. , When the wind wiper is operating, it is determined that the road surface is slippery due to rain or snow, and the inter-vehicle distance threshold is corrected to a longer value to avoid a rear-end collision. When the door is lit, it is determined that the dark outlook is bad, it was to correct a longer headway distance threshold for a rear-end collision accident avoidance.

[0006]

According to the above structure, it is possible to issue an inter-vehicle distance warning that matches the driving situation without using a special sensor.

[0007]

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

FIG. 1 shows a first warning system according to the present invention.
It is a block diagram of an Example.

In FIG. 1, reference numeral 1 is a laser radar for measuring an actual inter-vehicle distance. Reference numeral 2 is a vehicle speed sensor that detects the speed of the vehicle. Reference numeral 3 is a light switch operated by the driver or a signal from the brightness sensor, and reference numeral 4 is a wiper switch operated by a signal from the driver or a raindrop sensor. Turning on these switches activates the lights and wipers. Reference numeral 5 denotes an information processing unit, which is safe on the basis of the inter-vehicle distance signal from the laser radar 1, the vehicle speed by the vehicle speed sensor 2, the light lighting information from the light switch 3, and the wiper operation information from the wiper switch 4. Calculates a specific inter-vehicle distance threshold. Further, when the information processing unit 5 detects that the actual inter-vehicle distance detected by the inter-vehicle distance display device 7 is shorter than the set inter-vehicle distance threshold,
Alarm generator 6 consisting of display, speaker, etc.
Use to alert the driver.

FIG. 2 is a flow chart showing the contents of calculation and processing of the information processing section 5. Hereafter, calculation according to FIG.
The processing cycle will be described.

First, the laser radar 1 measures the current inter-vehicle distance (R _n ) from the vehicle ahead. Then, using this R ₁ and the inter-vehicle distance (R _p ) detected one processing cycle before, the relative speed V _r is calculated as in the formula 1.

[0012]

[Equation 1]

However, ΔT is the time required for one processing cycle (constant value), and then the vehicle speed V is detected by the vehicle speed sensor 2. Then, using this V and V _r , the current reference safe inter-vehicle distance S
Determine _n . The reference safety inter-vehicle distance S _n is long when V is large, short when V is small, and when V _r is a positive value and large with respect to the reference safety inter-vehicle distance S _p determined one processing cycle before. Long, short when V _r is positive and small, short when V _r is negative and large, and long when V _r is negative and small.

Next, the reference safe inter-vehicle distance S _n is corrected according to the lighting condition of the lights and the operating condition of the wiper, so that the actual safe inter-vehicle distance S to be compared with the current inter-vehicle distance R _n with respect to the preceding vehicle is calculated. To do.

Now, it is determined by the light switch 3 whether or not the light is on, and if the light is on, the safe inter-vehicle distance is corrected as shown in equation (2).

[0016]

[Equation 2]

However, r is a constant that satisfies r> 1, but this value may be changed according to the lighting state of a small lamp, headlight on, high beam, or the like, or the vehicle speed V. Further, when the light is off, S _n is directly substituted into S as shown in Expression 3.

[0018]

[Equation 3]

Next, in each case of turning on and off the light, the wiper switch 4 determines whether or not the wiper is in operation. When the wiper is in operation, the safe inter-vehicle distance is corrected as shown in Formula 4. To do.

[0020]

[Equation 4]

However, w is a constant that satisfies w> 1, but this value may be changed according to the wiper operating conditions such as intermittent, normal, and high speed, or the vehicle speed V. If the wiper is stopped, S is retained as it is.

The safety inter-vehicle distance S corrected as described above is compared with the current inter-vehicle distance R _n between the preceding vehicle, and when R _n is shorter than S, a voice is given through the alarm generator 6 or
Visually, the current inter-vehicle distance is shorter than the safe inter-vehicle distance,
Warn that the distance between vehicles should be increased. Finally R
_p and S _p are updated, and one cycle of processing ends.

In this process, a process may be added in which the driver is always aware of the current inter-vehicle distance, the safe inter-vehicle distance, the vehicle speed, and the like to call attention.

Further, assuming that the vehicle runs on a slippery road surface such as a frozen road surface or a gravel road during fine daytime, it is desirable that the above-mentioned safe inter-vehicle distance can be set by a driver's judgment operation. .

In this embodiment, the laser radar is used for distance measurement, but the method is not limited to this.

[0026]

According to the present invention, a rear-end collision avoidance is avoided when the wind wiper is operating, that is, when the road surface is slippery due to rain or snow without using a special sensor in the inter-vehicle distance warning device. Therefore, the inter-vehicle distance threshold has been corrected to a longer value, and when the lights are in operation,
That is, when it is dark and the visibility is poor, or the front cannot be seen due to fog, the threshold value of the inter-vehicle distance can be corrected to be longer to avoid a rear-end collision, and the safety can be further improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing calculation / processing contents of an information processing unit.

[Explanation of symbols]

1 ... Laser radar, 2 ... Vehicle speed sensor, 3 ... Light switch, 4 ... Wiper switch, 5 ... Information processing part, 6 ... Alarm generation device.

Claims (1)

[Claims] 1. A means for detecting an inter-vehicle distance to a surrounding vehicle which changes from moment to moment, a means for detecting a speed of the own vehicle, and an inter-vehicle distance to the surrounding vehicle detected by the inter-vehicle distance detecting means, From the threshold of the safe inter-vehicle distance set by the speed of the own vehicle detected by the vehicle speed detection means and the relative speed obtained from the time change of the inter-vehicle distance with the surrounding vehicles detected by the inter-vehicle distance detection means. If it is short, in a warning system having means for giving a warning to the driver, it has a wind wiper operation information detecting means, and when the wind wiper is operating, the threshold value of the safe inter-vehicle distance is corrected to be long. An inter-vehicle distance warning system characterized in that