JP4505968B2 - Self-vehicle position detecting device and self-vehicle position detecting method during parking - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a self-vehicle position detection device at the time of parking that assists a steering operation by allowing a driver to recognize the relative position between a partition line that partitions the parking space and the own vehicle when the vehicle enters the parking space. And a vehicle position detection method .
[0002]
[Prior art]
Generally, in a parking lot where a vehicle is parked, a partition line such as a white line or a yellow line is drawn on the road surface to partition the parking space. When the driver parks the vehicle, the vehicle is moved backward or forward. Then, an operation of entering the parking space separated by the partition line is performed. Here, when entering the parking space while moving the vehicle back, check the left and right rearview mirrors or look directly behind the vehicle to grasp the positional relationship between the vehicle and the partition line. Need to retreat. Further, when the host vehicle does not fit in the parking space, it is necessary to perform an operation of once moving the vehicle forward and then moving backward again.
[0003]
Therefore, for example, a device described in Japanese Patent Application Laid-Open No. 10-83500 (hereinafter referred to as a conventional example) is known as a vehicle position detection device for easily performing such a driving operation. In the conventional example, an image sensor is attached to the bottom surface of the vehicle, a white line on the road surface is imaged, and image processing is performed to obtain an angle formed by the white line and the vehicle. Then, by displaying the obtained angle data as a symbol on a display screen installed at an appropriate position of the driver's seat, the driver can recognize the positional relationship of the vehicle with respect to the white line. With such a configuration, the driver can grasp the angle between the partition line that partitions the parking space and the host vehicle, which is useful when the vehicle is moved backward and enters the parking space.
[0004]
[Problems to be solved by the invention]
In the conventional vehicle position detection device for assisting parking operation, a partition line that partitions the parking space is recognized, an angle formed by the partition line and the vehicle is obtained, and the symbol is displayed on the monitor screen. I have to. Therefore, since only the angle between the partition line of the parking space and the own vehicle is detected, the driver can recognize the angle between the partition line and the own vehicle, but in the front-rear direction in the parking space. The positional relationship cannot be recognized. That is, it is not possible to grasp whether the tail of the vehicle has reached the rear end of the parking space. Therefore, since the front-rear relationship between the parking space and the host vehicle is not recognized, there is a drawback in that it is impossible to grasp the sense of distance in the front-rear direction when the vehicle enters the parking space.
[0005]
The present invention has been made in order to solve such a conventional problem. The object of the present invention is to drive the angle between the vehicle and the partition line and the position of the vehicle in the front-rear direction with respect to the parking space. It is to provide a vehicle position detection device and a vehicle position detection method during parking that can be recognized by a person.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 of the present application takes an image of a partition line that divides a parking space, detects a positional relationship between the partition line and the host vehicle, and displays the detected positional relationship on a screen. A vehicle position detection device for parking that informs the driver, which is installed in a vehicle, picks up an image around the vehicle, extracts a partition line from the image picked up by the image pickup means, and An image processing unit for obtaining a reference position on a line segment forming a partition line and an inclination angle of the partition line with respect to a preset reference direction, and a reference position and an inclination angle obtained from the image processing unit, the image Upper vehicle position calculation means for calculating the relative position of the vehicle with respect to the partition line, and display means for displaying the relative position between the vehicle and the partition line calculated by the vehicle position calculation means. And the reference position is The extracted partition line is set to one end point existing at a portion other than the corner on the image, and when the set one end point reaches the corner on the image, the extracted partition It is characterized in that it is set to the other end point existing in a part of the line segment other than the corner on the image.
[0007]
According to a second aspect of the present invention, when the image processing means includes a plurality of partition lines in the image captured by the imaging means, the longest one of the plurality of partition lines is selected. It is characterized by extracting.
[0009]
According to a third aspect of the present invention, the image processing means creates a bird's-eye view image based on the image picked up by the image pickup means, and the display means includes a host vehicle and a partition line on the bird's-eye view image. The relative position of is displayed.
The invention according to claim 4 captures a partition line that divides the parking space, detects a positional relationship between the partition line and the host vehicle, displays the detected positional relationship on a screen, and informs the driver during parking. An own vehicle position detection method, in which an image around a vehicle is picked up by an image pickup unit installed in the vehicle, a partition line is extracted from the image picked up by the image pickup unit, and a line segment forming the partition line is extracted. An inclination angle of the partition line with respect to a reference position and a preset reference direction is obtained by an image processing means, and the reference position and inclination angle obtained from the image processing means are used to determine the angle of the partition line on the image. The vehicle relative position is calculated by the vehicle position calculation means, the relative position between the vehicle and the partition line calculated by the vehicle position calculation means is displayed by the display means, and the reference position is the extracted partition Line segment It is set to one end point that exists in a part other than the upper corner, and when the set one end point reaches the corner on the image, it is not the corner on the image of the segment of the extracted partition line. It is characterized by being set to the other end point existing in the part.
[0010]
【The invention's effect】
According to claim 1 or claim 4 vehicle position detecting device or the vehicle position detecting method of a parking time according to the end point of the line segment forming the partition lines for partitioning the parking space is set as a reference point, the reference point position Based on the angle of the partition line with reference to this reference point, the position of the vehicle relative to the partition line is obtained and displayed on the display means. Accordingly, the driver can easily and surely recognize the position of the vehicle with respect to the partition line, so that the garage entry operation into the parking space can be performed very easily.
At this time, since the end point that is not the corner on the screen of the line segment that forms the extracted partition line is selected as the reference point, the optimum point can always be selected as the reference point.
[0011]
In the vehicle position detecting device at the time of parking according to claim 2, when the presence of a plurality of partition lines is confirmed, the longest of these is selected and extracted. Can be extracted.
[0013]
In the self-vehicle position detection device at the time of parking according to the third aspect , the relative position between the own vehicle and the partition line is displayed on the bird's-eye view image, so that the driver can objectively confirm the own vehicle position.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG.
[0015]
Reference numeral 1 denotes a vehicle position detection device.
[0016]
Reference numeral 5 denotes a rear camera that is arranged behind the vehicle and images a predetermined range behind the host vehicle.
[0017]
Reference numeral 6 denotes an auxiliary camera that images a parking space in advance, and details will be described later.
[0018]
Reference numeral 4 denotes a parking monitor switch provided near the driver's seat. The parking monitor switch is turned on when the driver directly operates, and an image of the rear camera 5 can be obtained. The parking monitor switch 4 may be turned on when it is detected that the vehicle has entered.
[0019]
Reference numeral 7 denotes a memory that stores images taken by the rear camera 5 and the auxiliary camera 6.
[0020]
Reference numeral 3 denotes a monitor provided in the passenger compartment, on which an image that has been subjected to processing to be described later is displayed.
[0021]
A controller 2 includes peripheral components such as a CPU, a ROM, and a RAM, and executes a control program stored in the ROM.
[0022]
FIG. 2 is an explanatory diagram showing an imaging area behind the host vehicle 9 captured by the rear camera 5, and the rear camera 5 can capture a trapezoidal area indicated by reference sign S <b> 1 behind the host vehicle 9. . FIG. 3 is an explanatory diagram showing an area imaged by the rear camera 5 when another vehicle 10 is parked on both sides of the parking space, and the presence of the other vehicle 10 is monitored 3 during the parking operation. You can check above.
[0023]
FIG. 4 is a flowchart showing a control program stored in the controller 2, and the operation of the present embodiment will be described using this flowchart.
[0024]
When the driver turns on the parking monitor switch 4 in the vicinity of the driver's seat of the own vehicle 9 (YES in step ST1), the rear camera 5 is activated to capture a rear image of the own vehicle 9 (step ST2).
[0025]
And the process which changes the viewpoint of the image imaged with the back camera 5 and obtains a bird's-eye view image is performed. As a result, the rear image as shown in FIG. 5A is converted into a bird's-eye view image as shown in FIG. Subsequently, the process which detects the white line (partition line) contained in this bird's-eye view image is performed (step ST3). If no white line is detected (NO in step ST4), the driver is notified by the monitor 3 that parking operation is difficult in the current situation (step ST5). The same processing is also performed when a white line is detected once but is not detected immediately thereafter.
[0026]
On the other hand, when it is detected that a white line is present in the bird's-eye view image, processing for obtaining one end point of the white line is performed (step ST6). FIG. 6 is an explanatory diagram showing the concept of a method for obtaining the end point of the white line. The brightness in the bird's-eye view image is compared with a predetermined threshold value for each pixel. If it is less than the value, a so-called binarization process is performed, in which the pixel value is changed from “0” to “1”, and the pixel value is changed from “1” to “0”. The pixel Q2 is extracted and edge processing is performed. A straight line S intermediate between the straight line connecting the pixels Q1 and the straight line connecting the pixels Q2 is detected as a white line center line, and a point P that is an end of the straight line S is obtained as an end point.
[0027]
Note that, by detecting a line as described above and determining the degree of straightness of the line with a predetermined threshold value, it is possible to prevent an object that becomes a curve such as a puddle from being erroneously recognized as a white line.
[0028]
Then, it is determined whether or not the position of the obtained end point is at the corner of the bird's-eye view image. If it is not at the corner (NO in step ST7), this end point is set as a reference point (step ST9). On the other hand, if it is determined that it is in the corner (YES in step ST7), the other end point of the white line is obtained and a process using this as a reference point is performed (step ST8).
[0029]
Then, when the reference point is set in the above-described steps ST8 and ST9, a process for obtaining an angle formed by a line segment from the reference point toward the white line and the reference direction on the image is performed (step ST10).
[0030]
FIG. 7 is an explanatory diagram schematically showing the processing procedure of steps ST6 to ST10 described above. When the white line image W1 as shown in FIG. 7A is extracted and the end point P1 is designated, FIG. Since this end point P1 is not at the corner of the image, it is set as a white line reference point, and the angle θ1 formed by the white line direction Y2 relative to this reference point and the reference direction Y1 on the image is obtained.
[0031]
Thereafter, when the own vehicle 9 moves and the end point P1 on the white line W1 reaches the corner of the image as shown in FIG. 8B, this time, the opposite of the white line W1 as shown in FIG. The end point P2 on the side is set as a reference point, and an angle θ2 formed by the direction Y3 of the white line W1 with reference to this reference point and the reference direction Y1 on the image is obtained.
[0032]
The white line W1 is based on the mounting position of the rear camera 5, the position of the reference points (P1, P2) in the image obtained by the above-described processing, and the angle (θ1, θ2) between the white line W1 and the reference direction Y1. And a process for obtaining a positional relationship between the vehicle 9 and the host vehicle 9 (step ST11). And the image which superimposed the image of the own vehicle 9 on the bird's-eye view image of a parking space is displayed on the monitor 3 (step ST12).
[0033]
The driver can easily recognize the position of the own vehicle 9 with respect to the parking space by looking at the image on the monitor 3, so that the operation of entering the parking space while reversing the vehicle is extremely easy. To be able to do that.
[0034]
FIG. 8 is a diagram showing the selection of the reference point shown in FIG. 7 for each parking phase. When the area S1 shown in FIG. Is obtained. Thereafter, even when the vehicle moves and enters the phase shown in FIG. 5B, the end point P11 is not at the corner of the image, and is therefore selected as a reference point.
[0035]
Further, when the parking operation proceeds to the position shown in FIG. 5C, the reference point moves to the end point P12 on the opposite side, and as shown in FIG. The position is selected as a reference point.
[0036]
In the above procedure, when parking, there is always a parking space behind, and if two white lines that determine the parking space are drawn on the road surface, at least one of the two white lines farthest from the vehicle The end point of is an algorithm that effectively utilizes the fact that it always exists on the imaging screen of the rear camera 5 having a certain angle of view.
[0037]
Thus, in this embodiment, the white line (partition line) which partitions a parking space is imaged with the rear camera 5, the reference position is set on the white line, and the angle formed by the white line and the vehicle 9 is set. Based on the obtained result, the vehicle position relative to the parking space is detected and displayed as an image. Accordingly, since the vehicle position relative to the parking space can be accurately displayed on the screen, the driver can easily and surely enter the vehicle 9 into the parking space.
[0038]
Further, the rear image captured by the rear camera 5 is converted into a bird's-eye view image, and the image of the host vehicle 9 is displayed superimposed on the bird's-eye view image, so that the host vehicle position can be viewed objectively. Furthermore, when the parking monitor switch 4 is configured to be turned on in conjunction with the shift lever of the vehicle being put into the back gear, the driver switches the parking monitor switch 4 every time the parking operation is performed. The operation of throwing in can be omitted, and the operability is good.
[0039]
In the above-described embodiment, the image captured by the rear camera 5 is converted into a bird's-eye view image, and the image of the vehicle 9 is superimposed on the bird's-eye view image and displayed on the monitor 3, thereby Although it is configured to recognize the positional relationship with the own vehicle, it is also possible to project the own vehicle on the image of the parking space previously captured by the auxiliary camera 6.
[0040]
FIG. 9 is an explanatory view showing an example of a parking space image captured in advance by the auxiliary camera 6 and stored in the memory 7. Reference numeral S11 shown in FIG. 9 indicates an imaging range of the parking space image. Then, as shown in FIG. 10, the two end points of the white line 71 included in the parking space image S11 are set as P21 and P22, and the reference position obtained by the processing of steps ST8 and ST9 in the flowchart shown in FIG. By aligning the end points (points P11 and P12 shown in FIG. 8) with the end points P21 and P22 on the parking space image S11, the image of the host vehicle 9 is displayed superimposed on the parking space image S11. Can do. As a result, an image as shown in FIG. 11 is displayed on the monitor 3.
[0041]
If such a display method is used, the driver can confirm the parking operation of the own vehicle 9 while viewing the objectively displayed image such that only the image of the own vehicle 9 moves without moving the background. It is possible to further facilitate the operation of entering the own vehicle 9 into the vehicle space.
[0042]
In the above-described embodiment, the white line has been described as an example of the partition line that partitions the parking space. However, it is needless to say that the present invention can be applied to other partition lines such as a yellow line.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an embodiment of a vehicle position detection device at the time of parking according to the present invention.
FIG. 2 is an explanatory diagram showing a range of a rear visual field of the own vehicle imaged by a rear camera.
FIG. 3 is an explanatory diagram showing a rear visual field imaged by a rear camera when the host vehicle enters the parking space.
FIG. 4 is a flowchart showing the operation of the present embodiment.
5A is an explanatory diagram illustrating an image captured by a rear camera, and FIG. 5B is an explanatory diagram illustrating a bird's-eye view image obtained from the image.
FIG. 6 is an explanatory diagram showing an operation of extracting an end point of a white line.
FIG. 7 is an explanatory diagram illustrating a method for setting a reference position and setting a white line angle;
FIG. 8 is an explanatory diagram showing a change in the reference position accompanying the movement of the own vehicle.
FIG. 9 is an explanatory diagram showing an image captured by an auxiliary camera.
FIG. 10 is an explanatory diagram showing how a reference point is set on a white line included in an image captured by an auxiliary camera.
FIG. 11 is an explanatory diagram showing a state in which a host vehicle is displayed on an image captured by an auxiliary camera.
[Explanation of symbols]
1 Vehicle position detection device 2 Controller 3 Monitor (display means)
4 Parking monitor switch 5 Rear camera (imaging means)
6 Auxiliary camera 7 Memory

Claims (4)

An image of a partition line that divides a parking space, detects a positional relationship between the partition line and the own vehicle, and displays the detected positional relationship on a screen to inform the driver of the vehicle position detection device during parking,
An imaging unit installed in the vehicle and capturing an image around the vehicle;
An image processing unit that extracts a partition line from an image captured by the imaging unit, obtains a reference position on a line segment that forms the partition line, and an inclination angle of the partition line with respect to a preset reference direction;
Vehicle position calculation means for calculating the relative position of the vehicle with respect to the partition line on the image from the reference position and the inclination angle obtained from the image processing means;
Display means for displaying a relative position between the own vehicle and the partition line calculated by the own vehicle position calculating means;
Comprising
The reference position is set to one end point existing in a portion other than the corner on the image of the extracted segment line, and at the time when the set one end point reaches the corner on the image. The vehicle position detecting device at the time of parking, characterized in that it is set to the other end point existing at a portion other than the corner on the image of the extracted segment line .   The image processing means extracts the longest one of the plurality of partition lines when there are a plurality of partition lines in the image picked up by the image pickup means. Self-vehicle position detection device at the time of parking. The image processing unit creates a bird's-eye view image based on the image captured by the imaging unit, and the display unit displays a relative position between the host vehicle and the partition line on the bird's-eye view image. The own vehicle position detection device at the time of parking according to claim 1 or 2 . It is a vehicle position detection method at the time of parking by imaging a partition line that divides a parking space, detecting a positional relationship between the partition line and the own vehicle, and displaying the detected positional relationship on a screen to inform the driver,
An image around the vehicle is captured by an imaging means installed in the vehicle,
A partition line is extracted from an image captured by the imaging unit, a reference position on a line segment forming the partition line, and an inclination angle of the partition line with respect to a preset reference direction are obtained by an image processing unit.
From the reference position obtained from the image processing means and the inclination angle, the vehicle relative position on the image on the image is calculated by the vehicle position calculating means,
The relative position between the own vehicle and the partition line calculated by the own vehicle position calculating means is displayed by the display means,
The reference position is set to one end point existing in a portion other than the corner on the image of the extracted segment line, and when this one end point reaches the corner on the image, Set to the other end point of the extracted segment line segment that is not in the corner of the image
A method for detecting a position of a vehicle at the time of parking .

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