JPH0528399A - Auto cruising device - Google Patents

Abstract

PURPOSE:To provide an auto cruising device to perform the automatic speed control with high safety by paying attention to the automobile interval distance with the vehicle before and after the self-vehicle. CONSTITUTION:From an image obtained by a forward image pick-up means 1 and a backward image pick-up means 2, the backward and forward vehicles are recognized by a forward vehicle recognizing means 6 and a backward vehicle recognizing means 7, and the automobile interval distance with the recognized backward and forward vehicles is counted by a forward automobile interval distance counting means 8 and a backward automobile interval distance counting means 9. By a vehicle control judging means 10, the vehicle control is judged from the automobile interval distance before and after the self-vehicle, the travelling speed obtained by an automobile speed detecting means 3, the speed limit obtained by a speed limit input means 4, and a cruising speed 5 set by a cruising speed setting means 5. Based on the judgment, the speed control is performed by an automobile speed control means 12 and an alarm is generated from an alarm means 11 as needed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic cruise device for automatically controlling the speed of a vehicle such as an automobile.

[0002]

2. Description of the Related Art Conventionally, as an auto cruise device of this type, as described in, for example, Japanese Patent Laid-Open No. 64-66712, an image in front of the vehicle is input from a CCD camera installed in the front of the vehicle. In some cases, the front vehicle is recognized from the obtained image, and the speed of the own vehicle is controlled based on the distance between the recognized front vehicle and the own vehicle.

[0003]

However, in such a conventional auto-cruise device, since the speed of the host vehicle is controlled only from the inter-vehicle distance to the vehicle in front,
Acceleration / deceleration is performed regardless of the inter-vehicle distance to the other vehicle behind. Therefore, when the distance between the front vehicle and the front vehicle suddenly decreases, the rear vehicle may rapidly decelerate even when the rear vehicle is close to the host vehicle, and there is a possibility that the rear vehicle may collide with the rear vehicle. Was there.

The present invention solves the problems as described above, and pays attention not only to the inter-vehicle distance to the vehicle existing in front of the host vehicle but also to the relative positional relationship to the vehicle existing in the rear. The purpose of the present invention is to provide an auto-cruise device that performs highly safe automatic speed control.

[0005]

In order to achieve the above object, according to the present invention, a front imaging means for front photographing, a rear imaging means for rear photographing, and a vehicle speed for detecting a vehicle speed are mounted on a vehicle. Detecting means, speed limit setting means for setting a speed limit on a traveling road, cruising speed setting means for setting cruising speed, and forward vehicle recognizing means for recognizing a forward vehicle from an image captured by the front image capturing means. A rear vehicle recognizing means for recognizing a rear vehicle from an image captured by the rear image capturing means, and a front inter-vehicle distance calculating means for calculating an inter-vehicle distance between the front vehicle and the own vehicle recognized by the front vehicle recognizing means. A rear inter-vehicle distance calculating means for calculating the inter-vehicle distance between the rear vehicle and the own vehicle recognized by the rear vehicle recognizing means, and a front distance calculated by the front inter-vehicle distance calculating means. Inter-vehicle distance and rear inter-vehicle distance calculated by the rear inter-vehicle distance calculating means, own vehicle speed detected by the vehicle speed detecting means, speed limit set by the speed limit setting means, and cruise speed setting means set by the cruise speed setting means Vehicle control determination means for determining the vehicle control of the own vehicle from the cruising speed, and warning means for issuing a warning to the rear vehicle based on the determination by the vehicle control determination means,
An apparatus including a vehicle speed control means for controlling the speed of the host vehicle based on the judgment by the vehicle control judgment means is set as the problem solving means.

[0006]

According to the present invention, the above-mentioned means for solving the problems makes it possible to take into consideration not only the inter-vehicle distance to the other vehicle existing in the front, but also the relative positional relationship to the other vehicle existing in the rear.
In the situation where the rear vehicle is close to the vehicle, the automatic speed control with high safety can be realized because the vehicle does not suddenly decelerate even if the inter-vehicle distance with the vehicle in front becomes narrow.

[0007]

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

FIG. 1 is a block diagram showing the basic construction of an embodiment of the present invention. Reference numeral 1 is a front imaging means for photographing the front of the vehicle, and 2 is a rear imaging means for photographing the rear of the vehicle. As shown in FIG. 2, the front image pickup unit 1 and the rear image pickup unit 2 are realized by installing CCD cameras at the front and rear of the vehicle so as not to obstruct the driver's view. 3 is a vehicle speed detecting means for outputting the traveling speed V of the own vehicle in real time, and the output of the speedometer is used as its input. Reference numeral 4 denotes a speed limit setting means for setting the speed limit VL on the traveling road, which is input by the driver using a ten-key pad or the like. Reference numeral 5 denotes a cruise speed setting means for setting the cruise speed VC, which sets the traveling speed at the time when the setting switch is turned on as the cruise speed. Reference numeral 6 is a front vehicle recognition means for recognizing a front vehicle from the image captured by the front imaging means 1 by using an image processing technique, and 7 is an image captured by the rear imaging means 2.
Similarly, it is a rear vehicle recognition means for recognizing a rear vehicle using image processing technology. Reference numeral 8 is a front inter-vehicle distance calculating means for calculating the inter-vehicle distance F with the front vehicle recognized by the front vehicle recognizing means 6, and 9 is for calculating the inter-vehicle distance R with the rear vehicle recognized by the rear vehicle recognizing means 7. It is a rear inter-vehicle distance calculating means. Reference numeral 10 denotes a front inter-vehicle distance F calculated by the front inter-vehicle distance calculation means 8, a rear inter-vehicle distance R calculated by the rear inter-vehicle distance calculation means 9, and a vehicle speed detection means 3.
The vehicle control determination means for determining the vehicle control from the traveling speed V detected by the vehicle speed limit, the speed limit VL on the travel route set by the speed limit setting means 4, and the cruising speed VC set by the cruising speed setting means 5. Is. 1
Reference numeral 1 is a warning means for giving a warning to the rear vehicle when the vehicle control determination means 10 determines that the inter-vehicle distance to the rear vehicle is short. Specifically, the brake light of the host vehicle is turned on to prompt the rear vehicle to decelerate. 12
Is a vehicle speed control means for controlling the vehicle speed according to the judgment by the vehicle control judgment means 10, and controls the throttle actuator and the brake actuator.

FIG. 3 is a flow chart showing the operation of the auto cruise device in the embodiment of the present invention.

First, at step 101, the vehicle control parameter CNT is initialized, and the process proceeds to the following steps.

At step 102, the speed limit VL on the road is set by the speed limit setting means 4. In Figure 4,
The flow of a series of processes in the speed limit setting means 4 is shown.
Since the speed limit VL is different for each road, the driver recognizes the speed limit of the road on which the vehicle is traveling from road signs and the like, and when it is determined in step 201 that the speed limit VL needs to be changed, in step 202 Change the speed limit according to the road on which the vehicle is traveling. Conversely, the driver
If it is determined in step 201 that it is not necessary to change the speed limit VL, the state is left unchanged and step 1 in FIG.
Go to 03.

At step 103, the cruise speed VC is set by using the cruise speed setting means 5. FIG. 5 shows a flow of a series of processes in the cruise speed setting means 5. Cruising speed V
Since C needs to change according to the traffic situation and the psychological state of the driver, if the driver determines in step 301 that the cruising speed VC needs to be changed, in step 302, Change the cruising speed VC. On the contrary, when the driver determines that it is not necessary to change the cruising speed VC, the process proceeds to step 303 with the state unchanged.
In step 303, the cruise speed VC and the speed limit VL are compared in order to comply with the speed limit on the traveling road. If it is determined in step 303 that the cruising speed VC does not exceed the speed limit VL, the process proceeds to step 104 in FIG. On the contrary, when it is determined that the cruising speed VC exceeds the speed limit VL, the cruising speed limit VL is reset as the cruising speed VC in step 304, and then the process proceeds to step 104 in FIG.

In step 104, the vehicle speed detecting means 3 is used to input the traveling speed V of the host vehicle, and in step 105
And go to step 108. In order to reduce the processing time, the processing from step 105 to step 107 and the processing from step 108 to step 110 are
Do in parallel on different processors.

In step 105, an image of the front of the vehicle is input from the front image pickup means 1, and the process proceeds to step 106.
FIG. 9 shows the input image in front of the vehicle.

In step 106, the front vehicle recognition means 6
Is used to recognize the vehicle ahead from the input image. Figure 6
The flow of a series of processes in the front vehicle recognition means 6 is shown in FIG. First, in step 401, an edge is extracted from the input image in front of the vehicle. The extraction of edges is performed by applying a well-known spatial filter such as a Laplacian operator to the input image. The result of extracting the edges from the image of FIG. 9 is shown in FIG. Next, in step 402, a white line on the road is detected based on the edge image obtained in step 401. The white line is detected by using the HOUGH conversion method in which the straight line represented on the XY coordinates is coordinate-converted into a point on the θ-ρ coordinate. As shown in FIG. 14, ρ is the length of the perpendicular line drawn from the straight line on the XY coordinates to the origin, and θ is the angle formed by the perpendicular line with the X axis.
At this time, the straight line L on the XY coordinates shown in FIG.
It is represented as a point P on the ρ-θ coordinate as shown in. Conversely, a group of straight lines that can pass the point P _A on the XY coordinates is represented as a straight line L _A on the ρ-θ coordinates. Similarly, a group of straight lines that can pass through the point P _B on the XY coordinates is ρ−
It is represented as a straight line L _B on the θ coordinate. At this time, straight line L
The intersection point P between _A and the straight line L _B is the straight line L on the XY coordinates.
Corresponding to. In accordance with such a principle, it is possible to detect a straight line on an image by combining a sequence of points having continuity or removing an isolated point having no continuity. Figure 1
FIG. 11 shows an image in which a white line is detected from the edge image of 0. Further, in step 403, the trapezoidal area surrounded by the two detected white lines, the detected uppermost scanning line of the white line, and the scanning line at the lower end of the image is set as the road area, and the area on the image is limited. .. FIG. 12 shows an image obtained by limiting the road area to the image of FIG. Step 4
In 04, when the horizontal edges are continuously detected in the vertical direction with respect to the scanning line in the limited road area, it is recognized that the vehicle exists ahead. The edge extraction in this case is performed by applying a Laplacian operator to the road area of the input image. FIG. 13 shows an image in which a vehicle ahead is recognized from the image of FIG.

In step 107 of FIG. 3, the inter-vehicle distance F between the front vehicle and the host vehicle thus recognized is calculated by the front inter-vehicle distance calculating means 8. The inter-vehicle distance can be easily calculated by associating each scanning line of the input image with the distance from the CCD camera on the road. For example, the distance to the lowest edge among the edge group corresponding to the front vehicle recognized on the image of FIG. 13 is calculated as the inter-vehicle distance to the front vehicle. At this time,
The distance F on the actual road corresponding to d shown in FIG. 13 is the inter-vehicle distance with the preceding vehicle.

Similar processing is performed for the rear vehicle. First, in step 108 of FIG. 3, an image of the rear of the vehicle is input from the rear imaging means 2, and the process proceeds to step 109.

In step 109, the rear vehicle recognition means 7 recognizes the rear vehicle based on the input rear image of the vehicle. FIG. 7 shows a flow of a series of processes in the rear vehicle recognizing means. First, in step 501, an edge is extracted from the input image, and then in step 502, a white line is detected. Next, based on the detected white line, the road area is limited in step 503, and the rear vehicle is recognized in step 504.
Proceed to step 110 of FIG.

In step 110, the inter-vehicle distance R with the rear vehicle thus recognized is calculated by the rear inter-vehicle distance calculating means 9.

In this way, the inter-vehicle distance F between the host vehicle and the front vehicle is parallelized by the processing from step 105 to step 107, and the inter-vehicle distance R between the own vehicle and the rear vehicle is parallel by the processing from step 108 to step 110. Is calculated and the process proceeds to step 111.

In step 111, the vehicle control determination means 10 determines the vehicle control using the speed limit VL, the cruise speed VC, the traveling speed V, the front inter-vehicle distance F, and the rear inter-vehicle distance R obtained as described above. Done in. FIG. 8 shows a flow of a series of processes in the vehicle control determination means 10. The vehicle control determination means 10 determines the positional relationship between the own vehicle and the front vehicle and the rear vehicle from the relationship between the front inter-vehicle distance F and the rear inter-vehicle distance R, and determines the positional relationship and the traveling speed V and cruising speed VC of the vehicle. Based on this, the vehicle control is judged. FIG.
FIG. 3 is a diagram showing the positional relationship between the host vehicle and the front vehicle and the rear vehicle. Reference numeral 14 is a host vehicle, 15 is a front vehicle, and 16 is a rear vehicle. Further, F is the inter-vehicle distance between the host vehicle and the front vehicle, R is the inter-vehicle distance between the rear vehicle, FS is the front safety inter-vehicle distance between the self-vehicle and the front vehicle, and RS is the rear safety inter-vehicle distance between the self-vehicle and the rear vehicle. And Here, the front safety inter-vehicle distance FS is the inter-vehicle distance at which the host vehicle can safely stop even when the front vehicle applies the sudden braking, and the rear safety inter-vehicle distance RS is when the own vehicle applies the sudden braking. In addition, it is the inter-vehicle distance that the vehicle behind can safely stop. It is assumed that these values are set according to the traveling speed of the vehicle.

At this time, paying attention to the relationship among F, R, FS, and RS, the relative positional relationship between the host vehicle and the front vehicle and the rear vehicle is as follows: (1) The distance between the front vehicle and the rear vehicle If the distance is sufficient (2) The distance to the vehicle ahead is sufficient, but the distance to the vehicle behind is short (3) The distance to the vehicle behind is sufficiently wide. , When the inter-vehicle distance to the front vehicle is short (4) The inter-vehicle distance to the front vehicle and the inter-vehicle distance to the rear vehicle can be divided into four.

In the case of (1), that is, step 60 in FIG.
If it is determined in step 1 that (F ≧ FS) and (R ≧ RS), the process proceeds to step 602, and if not, the process proceeds to step 607. In step 602, it is determined whether the vehicle speed exceeds the cruise speed. If it is determined in steps 602 and 603 that the host vehicle is traveling at a speed exceeding the cruise speed, step 60 is performed in order to reduce the speed to the cruise speed.
At -4, -1 is assigned to the vehicle control parameter CNT. On the contrary, if it is determined in step 602 that the cruise speed is not exceeded, 1 is substituted in the vehicle control parameter CNT in step 606 in order to accelerate to the cruise speed. If it is determined in step 603 that the vehicle is traveling at the cruise speed, the vehicle control parameter CNT is transmitted in step 605 in order to travel at the same speed.
Substitute 0 for.

In the case of (2), that is, when it is determined that (F ≧ FS) and (R <RS) in step 607, the process proceeds to step 608, and otherwise, the process proceeds to step 611. In step 608, it is determined whether or not the vehicle speed exceeds the cruise speed. If it is determined that the host vehicle is traveling at a speed equal to or higher than the cruising speed, the vehicle control parameter CNT is sent in step 609 to give a warning to the rear vehicle to decelerate and increase the inter-vehicle distance. Substitute 2 for. Conversely, when it is determined that the vehicle is traveling at a speed that does not reach the cruising speed, 1 is substituted in the vehicle control parameter CNT in step 610 in order to accelerate the vehicle and increase the inter-vehicle distance to the rear vehicle.

In the case of (3), that is, when it is determined in step 611 that (F <FS) and (R ≧ RS), step 612 is performed in order to decelerate and widen the vehicle-to-vehicle distance. At -1, the vehicle control parameter CNT is substituted with -1.

In the case of (4), that is, when it is determined in step 611 that (F <FS) and (R <RS), the vehicle is accelerated to increase the inter-vehicle distance to the vehicle behind and also decelerate. It is also dangerous to increase the distance between vehicles ahead. Therefore, in order to give a warning for decelerating the rear vehicle, 2 is substituted in the vehicle control parameter CNT in step 613.

Here, at step 613, 2 may be given to CNT and -1 may be given to CNT at the same time so that the own vehicle decelerates and a warning is given to the rear vehicle to prompt deceleration.

The warning means 11 and the vehicle speed control means 12 are based on the judgment regarding the vehicle control performed as described above.
To operate. If it is determined in step 112 of FIG. 3 that the vehicle control parameter CNT is set to 1, the process proceeds to step 113, and the vehicle speed control means 12 accelerates. In step 114, the vehicle control parameter CNT
If it is determined that -1 is set to, step 1
In step 15, the vehicle speed control means 12 decelerates. When it is determined in step 116 that CNT is set to 2, the process proceeds to step 117, and the warning means 11 issues a warning to the rear vehicle. When it is determined in step 116 that CNT is set to 0, the vehicle runs at a constant speed as it is.

By repeating the above processing for each image given at a constant sampling interval, the relative position with respect to other vehicles existing in front of and behind the vehicle is taken into consideration while considering the speed limit on the road. According to the relationship,
Highly safe automatic speed control can be performed.

In the embodiment of the present invention, the driver inputs the speed limit input means by using the ten-key pad. However, this is performed automatically by recognizing the speed limit from the road sign and the road display by image processing. The speed limit may be recognized from the road information written in the map data by combining with a navigation system. Further, the inter-vehicle distance calculating means is obtained from the correspondence between the scanning line and the distance on the road, but two cameras are installed in front of and behind the vehicle at regular intervals in the vehicle width direction to obtain a stereo. A stereoscopic technique for performing three-dimensional distance measurement from an image may be used, or a Doppler radar device, a laser radar device, or the like may be used.

As described above, according to this embodiment, the vehicle control determination means 10 determines the positional relationship between the host vehicle and the front vehicle and the rear vehicle from the relationship between the front inter-vehicle distance F and the rear inter-vehicle distance R. Since the judgment regarding the control of the vehicle is made based on the positional relationship and the traveling speed V and the cruising speed VC of the vehicle, even if the preceding vehicle suddenly stops, the vehicle stops safely without being hit by the following vehicle. can do.

[0032]

As described above, according to the present invention, not only the inter-vehicle distance to the other vehicle in front, but also the relative positional relationship to the other vehicle in the rear is taken into consideration, so that the rear vehicle is close to the vehicle. In such a situation, the automatic speed control with high safety can be performed because the vehicle does not suddenly decelerate even when the inter-vehicle distance from the vehicle ahead is narrowed.

[Brief description of drawings]

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

FIG. 2 is a diagram showing an example of mounting a camera on a vehicle.

FIG. 3 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the speed limit input means.

FIG. 5 is a flowchart showing the operation of the cruise speed setting means.

FIG. 6 is a flowchart showing the operation of a front vehicle recognition means.

FIG. 7 is a flowchart showing an operation of a rear vehicle recognition means.

FIG. 8 is a flowchart showing the operation of vehicle control determination means.

FIG. 9 is a diagram showing an input image.

10 is a diagram showing an image in which edges are extracted from the input image of FIG.

11 is a diagram showing an image in which a white line is detected from the edge image of FIG.

FIG. 12 is a diagram showing an image in which a road area is limited based on the image in FIG.

13 is a diagram showing a front vehicle recognized within the road region shown in FIG. 12;

FIG. 14 is a diagram showing an XY coordinate system.

FIG. 15 is a diagram showing a θ-ρ coordinate system.

FIG. 16 is a diagram showing a positional relationship between a host vehicle, a front vehicle, and a rear vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front imaging means 2 Rear imaging means 3 Vehicle speed detection means 4 Speed limit input means 5 Cruise speed setting means 6 Front vehicle recognition means 7 Rear vehicle recognition means 8 Front inter-vehicle distance calculation means 9 Rear inter-vehicle distance calculation means 10 Vehicle control determination means 11 Warning means 12 Vehicle speed control means

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location G01S 11/12

Claims (1)

Claim: What is claimed is: 1. A front image pickup device for forward image pickup, a rear image pickup device for rear image pickup, a vehicle speed detection device for detecting a vehicle speed, and a speed limit on a traveling road. The speed limit setting means for setting, the cruising speed setting means for setting the cruising speed, the front vehicle recognizing means for recognizing the front vehicle from the image captured by the front image capturing means, and the rear image capturing means for capturing. Rear vehicle recognizing means for recognizing the rear vehicle from the image, front inter-vehicle distance calculating means for calculating the inter-vehicle distance between the front vehicle and the own vehicle recognized by the front vehicle recognizing means, and the rear vehicle recognizing means. A rear inter-vehicle distance calculating means for calculating the inter-vehicle distance between the rear vehicle and the host vehicle, and a front inter-vehicle distance and the rear inter-vehicle distance calculating means calculated by the front inter-vehicle distance calculating means. Of the vehicle control of the own vehicle from the rear inter-vehicle distance calculated by the vehicle speed, the own vehicle speed detected by the vehicle speed detection means, the speed limit set by the speed limit setting means, and the cruising speed set by the cruising speed setting means. Vehicle control determining means for making a determination, warning means for issuing a warning to a rear vehicle based on the determination by the vehicle control determining means, and vehicle speed control for performing speed control of the own vehicle based on the determination by the vehicle control determining means An auto cruise device consisting of means.