JPH03296200A - Relative speed detecting device and collision preventing device - Google Patents

Abstract

PURPOSE:To inform a driver of dynamic information by detecting the relative speed between its own vehicle and a precedent vehicle or following vehicle from a road image. CONSTITUTION:The image of the road in front of or behind of its own vehicle is inputted by a video camera 11 and an edge process is carried out for the input image data to detect a lane display line where its own vehicle travels. A travel lane detecting means 13 judges the travel lane of its own vehicle from the detected lane display line and a vehicle detecting means 14 detects the presence of the vehicle from the horizontal edge component of the image in the travel lane. Further, the vehicle distance is found from the position where the detected vehicle and stored in a vehicle distance storage means 16. Thus, the difference between the vehicle distance detected by the vehicle distance detecting means 15 and the vehicle distance detected in a last image plane stored in the storage means 16 is used to find the relative speed of this vehicle to the precedent or following vehicle. Consequently, the driver is informed of the dynamic information automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a relative speed detection device and a collision prevention device used in vehicles and the like.

Conventional technology A block diagram of a conventional device is shown in FIG.

In FIG. 13, 131 is an imaging device, 132 is a road area recognition method, 133 is a feature extraction means, and 134 is a vehicle discrimination means.
recognizes a road area in the image, and if the recognized road area has a recess that is thought to have been caused by the presence of a preceding vehicle or a following vehicle, the area with the recess as the base is processed by the feature extraction means 133. Using this, the vehicle determining means 134 determines the presence of a vehicle. (Unexamined Japanese Patent Publication No. 1-
281600) Problems to be Solved by the Invention In the vehicle recognition device as described above, it is possible to detect the presence of a preceding vehicle or a following vehicle. The present invention solves the above-mentioned problems by detecting the relative speed between the own vehicle and the preceding vehicle or the following vehicle from road images, and using dynamic information when driving. The object of the present invention is to provide a relative speed detection device for a vehicle that can be provided to a person.

Means for Solving the Problems The present invention achieves the above-mentioned objects.The present invention provides a video camera that is attached to a vehicle and takes images of a road a certain distance ahead or behind at a certain period, and a lane lane is determined from the road image taken by the video camera. a lane display line detecting means for detecting a display line; a driving lane detecting means for detecting a driving lane in which a vehicle is traveling using the lane marking line detected by the lane indicating line detecting means; Vehicle detection means for detecting a vehicle traveling in the detected driving lane from a road image obtained from the video camera; and inter-vehicle distance detection for detecting the inter-vehicle distance from the host vehicle to the vehicle detected by the vehicle detection means. means, inter-vehicle distance storage means for temporarily storing the inter-vehicle distance detected by the inter-vehicle distance detection means, and one screen in which the inter-vehicle distance detected by the inter-vehicle distance detection means and the inter-vehicle distance storage means are stored. The present invention is a relative speed detecting device comprising a relative speed detecting means for detecting the relative speed of the vehicle detected by the vehicle detecting means with respect to the own vehicle using a difference in a previously detected inter-vehicle distance.

In addition to the above-mentioned relative speed detection device, the present invention also provides a risk judgment means for determining the degree of danger of the own vehicle from the relative speed of the preceding or following vehicle obtained by the relative speed detection device, and a notification from the danger judgment means that the own vehicle Alternatively, the system is equipped with a warning means for warning the driver of the following vehicle, and the vehicle is equipped with a warning means that warns the driver of the following vehicle, based on the relative speed and distance between the vehicles, and indicates that the vehicle is rapidly approaching the preceding vehicle or the following vehicle and there is a risk of a collision. The collision prevention device is characterized in that the warning means gives a warning to the driver when a collision is determined.

Function: In the relative speed detection device of the present invention configured as described above, first, a video camera is used to capture the scenery of the road in front or behind the own vehicle and the cars existing there as images.From this captured image data, By performing edge processing etc., the lane display line in which the vehicle is traveling is detected on the road, and the lane in which the vehicle is traveling is determined by the lane detection means from the detected lane display line. The presence of a vehicle is detected by the vehicle detection means from the components, and the inter-vehicle distance is calculated from the position of the detected vehicle in the driving lane and stored in the inter-vehicle distance storage means.This completes the operation of one cycle. This series of operations is repeated at a constant cycle. Using the difference between the inter-vehicle distance detected by the inter-vehicle distance detection means and the inter-vehicle distance detected one screen ago and stored by the inter-vehicle distance storage means, the self-vehicle The relative speed of the preceding vehicle or the following vehicle relative to the vehicle can be determined.

In addition to the above-mentioned relative speed detection, the present invention also detects the detected relative speed and inter-vehicle distance of the preceding vehicle, indicating that the own vehicle is approaching the preceding vehicle or the following vehicle, and that there is a risk of collision (f). The alarm means gives a warning such as light or sound to the driver of the own vehicle or the following vehicle,
Prevent collisions.

Embodiments Below, embodiments of the relative speed detection device of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a relative speed detection device according to a first embodiment of the present invention. In the figure, numeral 11 is a video camera that captures an image of the road a predetermined distance ahead or behind the vehicle. Reference numeral 12 denotes a lane marking line detecting means, which detects a lane marking line within a road image using an image processing method. Reference numeral 13 denotes a driving lane detecting means, which detects the lane in which the vehicle is traveling from the detected lane display line. A vehicle detection means 14 detects a vehicle by extracting horizontal edge components within the detected driving lane.

Reference numeral 15 denotes an inter-vehicle distance detecting means, which detects an inter-vehicle distance to the detected vehicle using the distance from the lower end of the image of the horizontal edge component detected by the vehicle detecting means 14. 1
6 is an inter-vehicle distance storage means that temporarily stores the inter-vehicle distance to the detected vehicle. Reference numeral 17 denotes relative speed detection means, which detects the relative speed of the vehicle with respect to the own vehicle.

Next, the operation of the relative speed detection device of this embodiment configured as described above will be explained with reference to the control flowchart shown in FIG. First, in step 21, a road image a predetermined distance ahead or behind the vehicle is captured from the video camera 11. FIG. 3 shows an example of a road image captured at this time.

Next, proceed to step 22 Lane indication line detection means 12
A lane marking line detection process is performed. To detect lane marking lines, edge components in the road image captured in step 21 are detected using an edge extraction filter such as the 5obel operator, and a set of edge components with sufficient length and angle as a lane marking line is extracted from the image. This can be done by searching horizontally from the center to the left and right.

However, the length and angle of edge components that satisfy the conditions for lane marking lines depend on the position and angle of the video camera attached to the vehicle. Next step 2
Proceed to 3. The driving lane detection means 13 performs a driving lane detection process.

The driving lane can be detected using the two lane marking lines detected in step 22.

That is, the driving lane can be defined as a triangle having three points as vertices: the intersection of the left and right lane display lines and the intersections of the left and right lane display lines and the edges of the image, or as a quadrangle or a pentagon including the corner at the bottom of the image. Figure 4 shows the third
An example is shown in which driving lanes are detected from the road image shown in the figure. In this example, even on a curved road, which is a straight road, a polygon surrounded by curved lines can be detected as a driving lane in the same way. Next, the process advances to step 24, where the vehicle detection means 14 performs vehicle detection processing. Vehicle detection ζ This can be done by searching for horizontal edge components within the travel lane detected in step 23, taking advantage of the fact that the vehicle after edge extraction contains many horizontal edge components. In Fig. 5, a vehicle is present in the road image taken from the video camera 11. In Fig. 6, a horizontal edge component indicating the presence of a vehicle is detected in the travel lane detected from the road image shown in Fig. 5. Here is an example. Next, the process advances to step 25. It is determined whether there is a horizontal edge component indicating the presence of a vehicle within the travel lane.

If a horizontal edge component indicating the presence of a vehicle is not detected, it is determined that no vehicle is present and the process returns to step 21. If a horizontal edge component indicating the presence of a vehicle is detected, the process proceeds to step 26a. Inter-vehicle distance detection processing is performed by the distance detection means 15. Since the vertical distance in the image corresponds to the inter-vehicle distance on the road, the detection of the inter-vehicle distance is performed by detecting the lower edge of the horizontal edge component of the vehicle detected in step 26, which is located at the lowest part of the image. It can be calculated using the distance from However, the correspondence between the vertical distance of the image and the actual distance on the road also depends on how the video camera is mounted. FIG. 7 shows an example in which the distance of the horizontal edge component from the bottom of the image is measured, and the vertical distance within the image corresponds to the inter-vehicle distance. Next, the process proceeds to step 27, where the relative speed detection means 17 detects the relative speed of the detected vehicle with respect to the own vehicle. The relative speed can be detected by utilizing the fact that the period at which road images are captured from the video camera 11 is constant. That is, the relative speed is detected by finding the difference between the inter-vehicle distance detected from the image one screen before, which is stored in the inter-vehicle distance storage means 16, and the newly detected inter-vehicle distance. Figure 8 shows two horizontal edge components detected within the driving lane.If the detected inter-vehicle distance in Figure 8 moves from 2 months to 2 months, it means that the vehicles are approaching, and vice versa.
When the vehicle moves from 1 to 1, it is detected that the vehicle is moving away. Also, the magnitude of relative velocity is shown in Figure 8.
It is calculated from the magnitude of the difference in the detected inter-vehicle distance as shown in .

Next, proceed to step 28. The inter-vehicle distance detected in this process by the inter-vehicle distance detection means 16 is newly stored.
Return to step 21.

In this embodiment, by determining the inter-vehicle distance to other vehicles at regular intervals, the dynamic relationship between the own vehicle and other vehicles can be detected, and the driver can use this to prevent collisions, etc. Useful information can be provided, and vehicle safety can be improved.

Next, embodiments of the collision prevention device of the present invention will be described with reference to the drawings. FIG. 9 is a block configuration diagram of a vehicle collision prevention device according to an embodiment of the present invention box 2, which has the same configuration as that of embodiment 1, and also includes the risk of collision based on the relative speed detected by the relative speed detection means 97. Risk assessment means 9
8, and a warning means 99 for giving a warning to the driver when the vehicle is judged to be in a dangerous state by the danger judgment means 98.

Next, the operation of the collision prevention device of this embodiment configured as described above will be explained with reference to the control flowchart shown in FIG. First, in step 101 it is checked whether the device is switched on. If the switch is not turned on at this time, no further processing is performed, thereby making it possible to avoid unnecessary activation of the device, for example, when a vehicle is running in a parking lot. Also, in other unnecessary cases, the alarm can be turned off in step 102 by turning off this switch.
It can also be turned into FF. If the switch of the device is ON, the process advances to step 103. The same processing as steps 21 to 28 of the first embodiment is performed up to step 10a.

However, a road image a predetermined distance ahead of the vehicle is captured from the video camera 91, a preceding vehicle is detected in step 106, and in step 106 the warning is ON.
If the preceding vehicle is not recognized in step 7, the alarm is turned off in step 102, and then step 10
Return to 1. Next, proceed to step 10b Risk judgment means 9
8, the degree of risk is determined. If it is determined from the detected relative speed that the host vehicle is rapidly approaching the preceding vehicle at a speed higher than a predetermined relative speed, in step 10c, the nine warning means are activated by sound, light, or display. After the warning is given to the driver, the process returns to step 101, and if it is determined that the vehicle is not approaching rapidly, the process returns to step 101 with the warning turned off in step 102.

As described above, according to this embodiment, the danger of the own vehicle is determined based on the relative speed of the vehicle ahead of the own vehicle and the distance between the vehicles, and the driver is warned with light and sound, thereby preventing a collision ahead. be able to.

In this example, the warning means uses a sound force and a light force (of course, a combination of these is also effective.Also, in this example, the warning means is used to prevent a collision from occurring). Danger 3-4 If the judgment means determines that it is dangerous, the speed control means is controlled to slow down the speed. This can also be easily achieved.

Next, a collision prevention device according to a third embodiment of the present invention will be explained with reference to the drawings. FIG. 11 ζ is a block configuration diagram of the vehicle collision prevention device of this embodiment, which has the same configuration as that of the first embodiment, including a vehicle speed detection means 118 for detecting the speed of the vehicle;
and a risk determination means 119 that determines the risk of collision from the inter-vehicle distance detected by the inter-vehicle distance detection means 115, the relative speed detected by the relative speed detection means 117, and the traveling speed of the vehicle detected by the vehicle speed detection means 118.
, and an alarm means 11a for giving a warning to the driver of the following vehicle when the vehicle is judged to be in a dangerous state by the danger judgment means 119. Next, the operation of this embodiment of the vehicle collision prevention system of the present invention constructed as described above will be explained with reference to the control flowchart shown in FIG. In steps 121 to 128, steps 101 to 5 of the second embodiment
- Processing similar to 108 is performed. A road image a predetermined distance behind the vehicle is captured from the video camera 111, and a following vehicle is detected in step 126. Next, the process advances to step 129, where the vehicle speed detection means 118 performs a vehicle speed detection process. Vehicle speed can be easily detected using a speedometer or the like. Next, the process proceeds to step 12a, where it is determined whether the inter-vehicle distance detected in step 128 is sufficiently safe with respect to the traveling speed of the vehicle detected in step 129.

If the following vehicle maintains a sufficiently safe following distance, the newly detected following distance is stored in the following distance storage means 116 in step 12b in step 128, and then the alarm remains OFF via step 122. Return to step 121, and if the following vehicle does not maintain a safe following distance, proceed to step 12ca Step 12
At step c, the relative speed detecting means 117 detects the relative speed of the following vehicle with respect to the sub-vehicle in the same manner as step 27 of the first embodiment. Next, in step 6-12d, the newly detected inter-vehicle distance is stored in the inter-vehicle distance storage means 116, and then the process proceeds to step 12e.

In step 12e, the risk determination means 119 determines the degree of risk. If the following vehicle is following without maintaining a safe following distance and is approaching further or trying to maintain the following distance, step 12
At f, a warning is given to the driver of the following vehicle. In this embodiment, the warning method is to directly connect the output from the danger judgment means to the rear brake light of the own vehicle, so that if the danger judgment means judges that it is dangerous, the stop lamp will be activated to determine whether or not the driver scans the brakes. It is configured so that it will fall regardless. When this warning to the following vehicle is finished, one cycle of operation ends.
Returning to step 121, the image is repeatedly read and the danger is judged, and the alarm continues until it is safe. If the following vehicle is trying to increase the following distance, a command to cancel the warning is sent in step 12e, and the process returns to step 121 with the warning turned off in step 122.

As described above, according to this embodiment, it is possible to judge the danger from the relative speed of the following vehicle to the own vehicle, the inter-vehicle distance to the following vehicle, and the traveling speed of the own vehicle, and to alert the following vehicle.
It is possible to prevent a rear-end collision by a following vehicle.

In this example, an attempt was made to turn on the own vehicle's brake lights as a method of transmitting a warning to the following vehicle.It is equally effective to turn on something other than the brake lights, for example, the hazard lamps. . Additionally, a separate indicator light may be provided to notify following vehicles that the distance between the vehicles has become extremely close.

Effects of the Invention As described above, the present invention can detect the relative speed between the host vehicle and the preceding or following vehicle, can provide dynamic information to the driver, and can prevent collisions between vehicles. Since it is very effective in prevention, vehicle safety can be greatly improved.

[Brief explanation of drawings]

Fig. 1 shows the block configuration of the vehicle speed detection device in the first embodiment of the present invention. Fig. 2 shows the control flow in the same embodiment of the present invention. Fig. 3 shows an image taken from a video camera. Figure 4 shows the driving lane detected from the image shown in Figure 3. Figure 5 shows an example where a vehicle is present in the road image taken from a video camera. Figure 6 shows the image shown in Figure 5. Figure 7 shows the means for detecting the distance between vehicles in the image. Figure 8 shows the relative speed between the vehicles. Figure 9 shows the block configuration of the vehicle collision prevention system in the second embodiment of the present invention, Figure 10 shows the control flow diagram in the same embodiment, and Figure 11 shows the vehicle collision prevention system in the third embodiment. FIG. 12 is a block diagram of the prevention device. FIG. 12 is a flowchart of control in the same embodiment. FIG. 13 is a block diagram of a conventional vehicle recognition device. 11... Video camera, 12... Lane display line detection means, 13... Driving lane detection means, 14.
... Vehicle detection means, 15... Inter-vehicle distance detection means,
16... Inter-vehicle distance detection means

Claims (3)

[Claims] (1) A video camera that is attached to a vehicle and captures images of a road a predetermined distance ahead or behind the vehicle at regular intervals, and a lane indicator line detection means that detects lane indicator lines from the road image captured by the video camera. a driving lane detecting means for detecting a driving lane in which a vehicle is traveling using the lane marking line detected by the lane marking line detecting means; a vehicle detecting means for detecting from a road image obtained from the video camera; a following distance detecting means for detecting an inter-vehicle distance from the own vehicle to the vehicle detected by the vehicle detecting means; the following distance storage means for temporarily storing the following distance between vehicles; and a relative speed detecting means for detecting the relative speed of the vehicle with respect to the host vehicle detected by the vehicle detecting means. (2) The relative speed detecting device according to claim 1, a risk determining means for determining the degree of danger of the own vehicle from the relative speed of the preceding vehicle and the inter-vehicle distance obtained by the relative speed detecting device, and notification of the risk determining means. and warning means for warning the driver based on the relative speed and inter-vehicle distance of the preceding vehicle detected by the relative speed detection device, the risk determining means determines that the own vehicle is rapidly approaching the preceding vehicle and a collision is detected. A collision prevention device characterized in that the warning means gives a warning to a driver when it is determined that there is a danger of the collision. (3) The relative speed detecting device according to claim 1, a risk determining means for determining the degree of danger of the own vehicle from the relative speed of the following vehicle obtained by the relative speed detecting device, and a following vehicle based on a notification from the risk determining means. comprising a warning means for warning the driver of the vehicle, and a traveling speed detecting means for detecting the traveling speed of the own vehicle,
When the following vehicle distance detected by the inter-vehicle distance detection means of the relative speed detection device is not a safe distance with respect to the traveling speed of the vehicle, the distance between the following vehicle and the own vehicle detected by the relative speed detection device is A collision prevention device characterized in that, if the danger judgment means detects from the relative speed that the following vehicle is approaching, the warning means gives a warning to the driver of the following vehicle.