JPH06274799A - Warning device for distance between two cars - Google Patents

Abstract

PURPOSE:To make the device highly reliable and inexpensive and to improve the safety at the time of driving by discriminating the degree of approaching of a still target for a driver's own vehicle by the use of a moving target and giving a warning according to the degree of approaching. CONSTITUTION:The device is provided with a means 101 for detecting the vehicle inter-distance for detecting a distance between the forward vehicle and a driver's own vehicle, means 103 for detecting the direction of the preceding car which detects the traveling state of the forward car, car-speed detecting means 102 detecting the car speed of the forward vehicle or the relative car speed, warning device 105 giving a warning to a driver, and arithmetic circuit 104 changing the degree of approaching of the still target for the driver's own vehicle when it is confirmed that plural moving targets are passed between the still target and the driver's own vehicle based on the information from respective means and controlling the timing of making a warning by the warning device 105.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-to-vehicle distance warning device for issuing a warning according to a vehicle-to-vehicle distance existing in front of a vehicle and, more particularly, to a plurality of vehicle-to-vehicle distance warning apparatuses. When the passing of the moving target is confirmed, the vehicle-to-vehicle distance warning device is configured to reduce the false alarm to the driver by controlling the warning timing of the stationary target to the own vehicle.

[0002]

2. Description of the Related Art An example of a conventional vehicular distance warning device is shown in FIG. This inter-vehicle distance warning device
As shown in FIG. 14, an inter-vehicle distance detecting means 1201 for detecting a distance and a direction between a detected target and a preceding vehicle using a scanning laser radar, a vehicle speed detecting means 1202 for detecting a vehicle speed, and an inter-vehicle distance detecting means 1201. And a safe inter-vehicle distance to the front vehicle based on the signal output from the vehicle speed detection means 1202, and an approach degree to the own vehicle in accordance with changes in the calculated safe inter-vehicle distance and the distance to the front vehicle. Arithmetic circuit 1203 and the arithmetic circuit 120
The alarm device 1204 gives a warning to the driver based on the signal from No. 3 to keep an appropriate inter-vehicle distance and calls attention.

Next, the operation will be described. When the distance between the detected target and the preceding vehicle is detected by the inter-vehicle distance detecting means 1201 and it is determined that the vehicle exists in front of the own vehicle, the arithmetic circuit 1203 detects the vehicle speed based on the vehicle speed information detected by the vehicle speed detecting means 1202. The relative speed with respect to the preceding vehicle and the vehicle speed of the own vehicle are calculated, and the safe inter-vehicle distance with respect to the front vehicle is calculated based on the calculated speed information, and further, the safe inter-vehicle distance and the distance with the front vehicle are calculated. The degree of approach to the host vehicle is calculated according to the change, and a control signal is output stepwise to a display device (not shown) and an alarm device 1204 to give a warning to the driver to maintain an appropriate inter-vehicle distance. I was calling attention.

[0004]

However, the conventional vehicle-to-vehicle distance warning device is configured to issue a warning by detecting the reflector of the vehicle in front, as shown in FIG. As described above, with respect to a reflector or the like installed on the road, there is a case where it is present in the own lane range as shown in FIG. 14 from the information on the distance and direction detected by the laser radar, and it is stationary. There is a problem in that the driver loses the reliability of the device and the role as a safety device is diminished because the vehicle cannot be distinguished from the vehicle in front and is erroneously determined to be a vehicle in front and outputs a display and an alarm. there were.

As a method for solving such a problem, a camera is used as a means for detecting a front vehicle, a front view is picked up by the camera, and a road shape, a front vehicle, and a road reflector are detected from the image signal. Although such a configuration is conceivable, in the current technology, obtaining the necessary information by image processing causes the cost of the device to increase, and particularly at night, the halo of the camera is lit by the lamp of the oncoming vehicle. Therefore, there is a problem that it is extremely difficult to put the camera into practical use as a vehicle detecting means in front.

The present invention has been made in view of the above, and when it is confirmed that a plurality of moving targets cross between the stationary target, which is detected to be present in front, and the host vehicle. ， It is possible to confirm the driving safety of the own vehicle by using the stationary target and the moving target, and to notify the driver of the degree of approach more accurately, which is highly reliable and at low cost. The purpose is to improve.

[0007]

In order to achieve the above object, the present invention provides an inter-vehicle distance detecting means for detecting a front vehicle and detecting an inter-vehicle distance between the own vehicle and the front vehicle, and traveling of the front vehicle. From the traveling state detecting means for detecting the state, the vehicle speed detecting means for detecting the vehicle speed or the relative vehicle speed of the vehicle in front, the warning means for issuing a warning to the driver, the inter-vehicle distance detecting means, the traveling state detecting means, and the vehicle speed detecting means. When it is confirmed that a plurality of moving targets pass between the stationary target and the own vehicle based on the information of 1., the degree of approach of the stationary target to the own vehicle is changed and the warning timing by the alarm means is controlled. An inter-vehicle distance warning device for a vehicle, which is provided with a computing means.

[0008]

The vehicle-to-vehicle distance warning device according to the present invention detects the state of the host vehicle and the distance and direction between the host vehicle and the preceding vehicle, and detects the detection signal of each target from the plurality of detected targets. The vector of each target is calculated based on the change of the distance and the angle, the stationary target is determined, and the degree of approach to the own vehicle is determined from the direction of the vector and the distance to the own vehicle. Next, when it is confirmed that a plurality of moving targets pass between the stationary target and the own vehicle among the detected stationary targets, the degree of proximity of the stationary target is calculated again. . Based on the calculated result, the driver is controlled not to give a display or an alarm until a predetermined degree of approach is reached, thereby reducing the occurrence of a false alarm.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a schematic configuration of a vehicle-to-vehicle distance warning device according to the present invention. In the figure, 101 is an inter-vehicle distance detecting means for detecting an inter-vehicle distance between a host vehicle and a forward vehicle using a scanning laser radar, 102 is a vehicle speed detecting means for detecting a vehicle speed or a relative vehicle speed of the front vehicle, and 103 is a front vehicle. It is a preceding vehicle direction detecting means for detecting the direction.

Further, 104 is each of the means 101 to 103 described above.
Is an arithmetic circuit configured to calculate the degree of approach of a vehicle ahead based on a signal from the input interface 104a that inputs various signals and sends the input signals to the data bus 104f, and executes various control processes. ROM 104b that stores a program for
It is composed of a CPU 104d that executes various processes according to the storage program of the M104b, a RAM 104c that stores results and data processed by the CPU 104d, and an output interface 104e that outputs control commands to the outside in a predetermined format to each unit. There is. Reference numeral 105 is an alarm device that issues a warning to the driver based on the control signal output from the arithmetic circuit 104.

Next, the operation will be described. Arithmetic circuit 1
Reference numeral 04 denotes inter-vehicle distance information between the own vehicle and the preceding vehicle detected by the inter-vehicle distance detecting means 101, and the vehicle speed detecting means 10
The vehicle speed information or the relative vehicle speed information of the front vehicle detected by 2 and the traveling direction information of the front vehicle detected by the preceding vehicle direction detection means 103 are input. In the arithmetic circuit 104, the ROM 10
When the CPU 104d executes a predetermined arithmetic control based on a control program stored in advance in 4b and the degree of approach to the vehicle reaches a predetermined level, the alarm device 105
And outputs a control signal to the alarm device 105 based on the control signal. Further, the detailed configuration and operation will be described below.

FIG. 2 is a block diagram showing a schematic structure of the optical laser radar device for a vehicle according to the present invention. In the figure, 201 is a light transmitter for scanning laser light, 202 is a light receiver for receiving the reflected laser light, 203 is a vehicle speed sensor as vehicle speed detecting means 102, and 204 is for amplifying a light reception signal received by the light receiver 202. An amplifier, 205 is a distance detection circuit as the inter-vehicle distance detecting means 101, 206 is a DA converter for converting a digital signal into an analog signal, 207 is a scanning device for driving and controlling the light transmitter 210, 2
Reference numeral 08 denotes a clock generator that generates a clock signal at regular time intervals.

Next, the operation will be described. The clock generator 208 generates a clock signal at fixed time intervals, the light transmitter 201 is driven by the clock signal, and the flat laser light L spread vertically from the light transmitter 201.
t is output in front of the vehicle. Further, the output laser light Lt hits and is reflected by a reflector such as a forward vehicle existing in front of the vehicle, and the reflected light Lr is received by the light receiving viewing angle θ.
The light is received by the light receiver 202. The reflected light received by the light receiver 202 is converted into an electric signal, amplified by the amplifier 204, and then input to the distance detection circuit 205.

The distance detection circuit 205 further receives the clock signal from the clock generator 208, and the distance detection circuit 205 receives the reflected light from the light receiver 202 at the time when this clock signal is input and via the amplifier 204. The light propagation delay time Td between the time when the electric signal is input and the time when the electric signal is input is substituted into the following equation to calculate the distance l to the reflector.

L = C × Td / 2, where C is the speed of light (3 × 10 ⁸ m / sec) The arithmetic circuit 104 swings the vertically elongated flat laser beam spread from the light transmitter 201 in the vertical direction. Between θ, the scanning angle control signal of a digital signal is converted into an analog signal via the DA converter 206 so as to scan the front of the vehicle in the horizontal direction, and is output to the scanning device 207.

The scanning device 207 is controlled by a scanning angle control signal from the arithmetic circuit 104, and drives and controls the light transmitter 201 within the swing angle θ. The swing angle θ is a swing angle between the swing angle θL to the left and the swing angle θR to the right with respect to the front center line of the vehicle, that is, θL <θ <θR.

In this scanning control, the clock signal is also input to the arithmetic circuit 104 in order to match the timing of the clock signal generated by the clock generator 208. Further, the arithmetic circuit 104 includes an amplifier 204
The amplified voltage V is input from the
The magnitude of the reflected light intensity is input to 4 as information. Further, the vehicle speed information is input from the vehicle speed sensor 203.

FIG. 3 shows another means for detecting the distance and direction of a vehicle ahead of the present invention. In the figure, 3
01 is a laser radar transceiver for measuring the distance between vehicles, 30
2 is a filter 303, a condenser lens 304, and a CCD
It is a lateral movement detector composed of an element assembly 305 and detecting the direction of a vehicle in front, and is equipped with a filter 303 inside so as to detect only the light of the wavelength of the laser radar. 305 is a reflector at the rear of the preceding vehicle OM ₂ .

In the CCD element assembly 305, CCD image pickup elements are arranged in a line or in a matrix, and the light from the laser radar transmitter / receiver 301 is received to detect the distance between the preceding vehicle OM ₂ and the vehicle. Detect the distance. That is, the lateral movement detector 302 is the laser radar transceiver 3
The reflector 30 of the preceding vehicle OM ₂ for irradiation by 01
It is configured to detect the reflected light reflected by 5. The structure for detecting only the light of the wavelength of the laser radar uses a shutter mechanism that is controlled so as to be synchronized with the cycle of the laser radar in addition to the filter 303, or after the light is received by the CCD element assembly 305. It can also be realized by filtering the signal.

4 and 5 are flow charts showing the processing operation in the arithmetic circuit 104 of the vehicular distance warning device according to the present invention. In FIG. 4, first, the vehicle signal (vehicle speed / brake / accelerator) is input (S40
1), the laser radar signal is detected (S402), and it is determined whether or not there is a signal in the front field of view (S403). Here, when it is determined that there is a signal in the front visual field,
Inputting the laser radar signal n (P _{1 to} P _n ) the distances L to the own vehicle and the existing angle θ are input (S40).
4). On the contrary, if it is determined in step S403 that there is no signal in the front visual field, the process returns to step S401.

After executing the processing of step S404, the number of laser radar signals is counted (t = t + 1).
(S405), the number of signals to be processed (k = k +
1) is executed (S406). Next, the distance Lk and the angle θk of the input Kth laser radar signal are corrected using the own vehicle signal (S407), and the velocity vector V of the preceding vehicle is corrected.
k is calculated (S408). After that, the above step S4
It is determined whether the target calculated in 07 and 408 is a moving target (S409). If it is determined that the target is a moving target, the counter Na is set to Na = Na + 1 Mat (La, θa). = Pk (Lk, θk) (S410). On the contrary, when it is determined in step S409 that the target is not the moving target, the counter Nb is set to Nb = Nb + 1 Mbt (Lb, θb) = Pk (Lk, θk) (S411). Furthermore, after executing step S410, ka = k is set (S412), and after executing step S411, kb = k is set (S41).
3).

Next, it is determined whether or not the count k = n (S414). At this time, when it is determined that k = n, it is determined that all the n input laser radar signals have been processed. It is determined that the counters k, a and b are initialized (S415). On the contrary, if it is determined in step S414 that k <n, then step S414
Returning to 406, similar processing is executed for the k + 1th preceding vehicle OM ₂ with k = k + 1.

After the counters k, a and b have been initialized in step S415, it is determined whether or not the moving target has passed in front of the front stop target based on the following processing. That is, the counter b = b + 1 is set, the stationary target is counted (S416), the counter a = a + 1 is set, the moving target is counted (S417), and it is determined whether La> Lb. A judgment is made (S418). That is, here, the distance between the stationary target Lat-1 and the moving target Lbt-1 at t-1 is compared. When it is determined in step S418 that La> Lb is not satisfied, the stopped object is closer to the host vehicle, and the process returns to step S417.
When it is determined that> Lb, the stopped object is farther from the host vehicle, and therefore Δθt (θa−θb) is calculated (S419).

Further, a comparison with Δθt-1 at t-1 hour is executed to judge whether or not the sign is reversed from the previous Δθt (S420). At this time, if it is determined that the sign is reversed from the previous Δθt, it is determined that the stationary target has passed, and Cb = Cb + 1 is set (S421), and C
It is determined whether or not b> 2 (S422). At this time, C
When it is determined that b> 2, it is determined that the moving object has moved in front of the stopped object at least twice, and the b-th stopped object is a road reflector, and Pkb = R is set (S42).
3). After that, a = Na is set, and the processing of this reflector is ended (S424).

On the contrary, in step S420,
When it is determined that the sign is not reversed from the previous Δθt, it is determined whether or not a = Na (S425), and a = N.
When it is determined that the value is not a, the process returns to step S417 and a = a + 1 is performed, and the same process is performed. On the contrary, if it is determined in step S425 that a = Na, it is further determined whether b = Nb (S426). If it is determined that b = Nb is not satisfied, the above step is performed. Returning to S416, the same processing is executed with b = b + 1. If it is determined in step S426 that b = Nb, it is assumed that the study of the reflector of the detected stationary target is completed, and Na and N
The initialization of b is executed (S427).

Next, in FIG. 5, the necessity of alarm for the detected target is calculated. That is, the count k of the detected target is set to k = k + 1 (S428), and it is determined whether or not Pk is on the own lane (S429). When it is determined that the vehicle exists on the own lane, the warning distance Ls is calculated from the calculated Pk vector, the distance to the own vehicle, and the own vehicle speed (S430), and the distance Lk ≦ Ls between the own vehicle and the target. It is determined whether or not (S431). When it is determined that Lk ≦ Ls, a warning is output from the alarm device 105 (S432). On the contrary, when it is determined in step S431 that Lk ≦ Ls is not satisfied, the safe inter-vehicle distance Ld is calculated (S433), and then whether or not the distance Lk ≦ Ld between the own vehicle and the target is satisfied. (S43
4), the distances Lk and Ld between the vehicle and the target are compared,
When it is determined that Lk ≦ Ld, it is further determined whether or not Pk is a reflector (S435), and when it is determined that Pk is not a reflector (Pk ≠ R), display output is executed ( S436). That is, Pk is judged to be an object of attention, and the distance from Pk is displayed to call the driver's attention. Then, it is determined whether or not the count k = n (S437).

On the contrary, in step S435,
When it is determined that Pk is a reflector (Pk = R), it is determined whether the count k = n (S43).
7), when it is determined that k = n, it is determined that all the n input laser radar signals have been processed, and k =
The process returns to step S401 shown in FIG. Also,
When it is determined that k <n, the above step S42
Returning to 8, the same processing is executed for the k + 1th forward vehicle with k = k + 1. In addition, the above step S42
In 9, it is determined that the vehicle is not on the own lane, and in step S434, Lk> Ld.
If it is determined that the above condition is satisfied, the process proceeds to step S437 and a predetermined process is executed.

Next, each process of the above flow chart will be described in more detail. First, the above step S408
A method of calculating the velocity vector Vk of the forward vehicle in FIG.

As shown in FIG. 6, the input signal Pk1 (L1, θ1) of the preceding vehicle and the signal Pk2 (L) after t seconds have been input.
2, θ2) are converted into X and Y coordinates with the own vehicle as the origin. That is, Pk1 (X1, Y1) = Pk1 (L1 × cos θ1, L
1 × sin θ1) Similarly, Pk2 (X2, Y2) = Pk2 (L2 × cos θ2, L
The respective coordinates are obtained as 2 × sin θ2).

If the host vehicle travels LB in the Y direction in t seconds (calculated from the vehicle speed of the host vehicle), the amount of movement LB
, The moving amounts ΔX and ΔY of the forward vehicle in the t seconds are ΔX = X2-X1 ΔY = Y2-Y1 + LB, respectively.

The traveling direction θK is calculated by θK = arctan (ΔX / ΔY).

Next, steps S414 to S426 described above.
The process will be described with reference to FIGS. 7 and 8. As shown in FIG. 7, when there is a reflector in front of the traveling own vehicle and a traveling front vehicle, both the own vehicle and the preceding vehicle travel at t + 1. At this time, the change of the signal input by the own vehicle is set with the own vehicle position as the origin.
Shown in (a) and (b).

From the input signal, the reflector is a stationary object,
After the forward vehicle is determined to be a moving object, as shown in FIG. 8A, at time t−1, the forward vehicle is closer to the reflector, and therefore step S419 in FIG. 4 is executed to determine the angle of the reflector. A difference Δθt−1 between θa and the angle θb of the vehicle ahead is calculated. Further, since the sign of Δθ has not been reversed, the passage determination is not performed as it is, and the process of step S425 in FIG. 4 is executed.

Next, as shown in FIG. 8 (b), when the vehicle in front passes through the reflector at time t, the previous 2
When the moving object is closer than the stationary object, Δθt is calculated again, and since the sign is different from the previous time, it is judged that the preceding vehicle has passed and the above-mentioned FIG. The process of step S421 is executed. In addition,
FIG. 4 is for detecting a moving target existing at a short distance from a stationary target and determining whether or not the moving target has passed between the stationary object and the own vehicle based on the angle change of the moving target. is there.

FIG. 9 is an explanatory view showing an example of a running scene, in which the forward vehicle and the own vehicle, which are shown by diagonal lines, show their respective positions before t seconds. Further, FIG. 10 is an explanatory diagram showing a data acquisition state when the target is detected in the traveling scene shown in FIG. 9 by the scanning type laser radar used in the present invention, and the coordinates around the own vehicle are the coordinates. It is represented by the system. In FIG. 10, the shaded circles represent the detected data t seconds before, and the white circles represent the newly detected data.

FIG. 11 is a flow chart showing an example of the tracking processing operation of the data detected as described above. In the figure, first, a vehicle signal (vehicle speed / brake / accelerator) is input (S1101), a laser radar signal is detected (S1102), and it is determined whether or not there is a signal in the front visual field (S1103). In this determination, when it is determined that the signal is present in the forward field of view enters the laser radar signal Q ₁ ~Q _m (S1104). On the contrary, if it is determined in step S1103 that there is no signal in the front visual field, the process returns to step S1101.

After the processing of step S1104 is executed, k = 1 i = 1 j = 1 R (j) = Qk is set (S1105), and the number of signals to be processed (k = k + 1) is executed ( S1106). Next, Qk
The distance LQk between -1 and Qk is calculated (S1107), and it is further determined whether or not LQk <LQb (arbitrary distance) (S1108). LQk <LQ
If it is determined that b, then j = j + 1 ni = j Ri (j) = Qk is set (S1109), and Ri (1) to Ri (1) to Ri
The representative point Ri of (j) is calculated (S1110). On the contrary, in the above step S1108, LQk <LQb
If it is determined that it is not, i = i + 1 j = 1 nj = j Ri (j) = Qk Ri = Qk is set (S1111).

After executing step S1110 or step S1111, it is determined whether or not the count k = n (S1112). When it is determined that k = n, NR = i is set (S1113), Further, it is judged that all the inputted n laser radar signals have been processed, and the counters k, i and s are initialized (S1114).

Next, the counter i = i + 1 is counted (S1115), and further, the counter s = s + 1 is counted (S1116), and the distance LRi between Ri and Ss is counted.
s is calculated (S1117). Then, based on the calculation result, it is determined whether or not LRis <LRb (arbitrary distance) (S1118), and LRis <LR.
If it is determined that b, the count (k = k + 1) of the signal to be processed is executed (S1119), then Pk = Ri Pk ′ = Ss is set (S1120), and s = NS is set. (S
1121). Also, in step S1112 above,
When it is determined that k = n is not satisfied, the above step S1
Return to 105.

Next, in step S1118,
After it is determined that LRis <LRb is not satisfied, or after the processing of step S1121 described above, it is determined whether or not s = NS (S1122). When it is determined that s = NS is not satisfied, the processing proceeds to step S1116 described above. Return. On the contrary, s
= NS, it is further determined whether i = NR (S1123), and when i = NR is not determined, the process returns to step S1115.
On the contrary, when it is determined that i = NR, k = NP
(S1124), and i, s, and k are further initialized (S1125). Then, the process returns to step S1101.

Next, the processing shown in FIG. 11 will be schematically described. In steps S1105 to 1114, of the acquired whole raw data (Q), the ones determined to be the same target in one scan are combined into one target (R). For example, as shown in FIG. 10, when a front vehicle or a reflector is detected, the number of reflectors is three and the number of front vehicles is two.
Although they are individually detected, they can be post-processed quickly by combining them into a single process as the same target. Therefore, data existing within an arbitrary distance (LQb) is judged to be continuous data of the same target, and a process of collecting m pieces of data into NR pieces is executed.

Further, the above steps S1115 to 1125
In the case of the determined target, in comparison with the previously captured data (S), within the arbitrary distance (LR
In the case of b), it is determined that the target is the same target, and the process for substituting P and P ′ as the continuously captured data is executed. That is, by this process, the white circle mark and the hatched circle mark shown in FIG. 10 are judged as the same target object, and the alarm judgment process of the target object is executed based on this data.

[0043]

As described above, according to the vehicle-to-vehicle distance warning device of the present invention, the vehicle-to-vehicle distance detecting means for detecting the vehicle ahead and detecting the vehicle-to-vehicle distance between the host vehicle and the vehicle ahead, A traveling state detecting means for detecting a traveling state of a vehicle, a vehicle speed detecting means for detecting a vehicle speed or a relative vehicle speed of a vehicle ahead, an alarm means for issuing a warning to a driver, the inter-vehicle distance detecting means, a traveling state detecting means, a vehicle speed. When it is confirmed that a plurality of moving targets pass between the stationary target and the own vehicle based on the information from the detection means, the degree of approach of the stationary target to the own vehicle is changed, and the warning timing by the alarm means When it is confirmed that a plurality of moving targets cross between the stationary target detected to exist in front and the own vehicle, the stationary target and the moving target are controlled. Use the mark Check the running safety of the vehicle Te, and can report the access degree more accurately to the driver, high reliability and can be inexpensively improved safety during operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a vehicle-to-vehicle distance warning device.

FIG. 2 is a block diagram showing a schematic configuration of an optical laser radar device for a vehicle.

FIG. 3 is an explanatory diagram showing another means for detecting the distance and direction of a vehicle ahead.

FIG. 4 is a flowchart showing a processing operation in an arithmetic circuit of the vehicle-to-vehicle distance warning device.

FIG. 5 is a flowchart showing a processing operation in an arithmetic circuit of the vehicle-to-vehicle distance warning device.

FIG. 6 is an explanatory diagram showing a method of calculating a velocity vector of a vehicle ahead.

FIG. 7 is an explanatory diagram showing a situation in which a reflector and a traveling front vehicle are present in front of a traveling own vehicle.

8 is an explanatory diagram showing a processing example in the situation shown in FIG. 7. FIG.

FIG. 9 is an explanatory diagram showing an example of a traveling scene.

FIG. 10 is an explanatory diagram showing a data acquisition state when a target is detected in the traveling situation shown in FIG. 9 by the scanning type laser radar used in the present invention.

FIG. 11 is a flowchart showing an example of data tracking processing operation.

FIG. 12 is a block diagram showing a schematic configuration of a conventional vehicle-to-vehicle distance warning device.

FIG. 13 is an explanatory diagram showing a problem of a conventional vehicle-to-vehicle distance warning device.

FIG. 14 is an explanatory diagram showing a problem of a conventional vehicle-to-vehicle distance warning device.

[Explanation of symbols]

 101 inter-vehicle distance detecting means 102 vehicle speed detecting means 103 preceding vehicle direction detecting means 104 arithmetic circuit 105 alarm device

Claims (1)

[Claims] 1. An inter-vehicle distance detecting means for detecting a front vehicle and detecting an inter-vehicle distance between the own vehicle and the front vehicle, a traveling state detecting means for detecting a traveling state of the front vehicle, and a vehicle speed or a relative vehicle speed of the front vehicle. A vehicle speed detecting means for detecting the vehicle speed, an alarming means for issuing a warning to the driver, a plurality of movements between the stationary target and the host vehicle based on the information from the inter-vehicle distance detecting means, the traveling state detecting means, and the vehicle speed detecting means. An inter-vehicle distance warning device for vehicle, comprising: a computing means for changing the degree of approach of the stationary target to the own vehicle when the passage of the target is confirmed, and controlling the warning timing by the warning means. .