JP4457664B2 - Parking assistance device - Google Patents

Description

  The present invention relates to a parking support device mounted on a vehicle, and more particularly to a parking support device that displays a vehicle image in three dimensions.

  Conventionally, when performing reverse parking in the parking area, the driver guides the vehicle to the parking position while confirming the position to be parked first, turning the steering wheel, and repeating forward and backward movements. This kind of parking operation has many points to watch out for, such as looking at the back with poor visibility with the naked eye and checking the front left and right of the vehicle when turning back. It is a difficult operation even for those who are rich.

In order to assist such a difficult parking operation, there is a system that captures the rear of the vehicle with a camera provided at the rear of the vehicle and displays the image on a back guide monitor. In this system, the camera image of the rear of the vehicle with a wide blind spot area is displayed on the back guide monitor in the vehicle, thereby reducing the blind spot area and making it easier for the driver to check the rear situation.
Regarding such a back guide monitor system, for example, there are the following documents.
JP 2002-321581

However, the image displayed on the back guide monitor is an image acquired through the lens of the camera, and since the back guide monitor screen and the predicted movement trajectory of the vehicle are two-dimensional planes, they are displayed on the screen. There is a problem in that there is no stereoscopic effect and it is difficult to sensuously sense the distance between the parking position and the current position and the current vehicle orientation with respect to the parking position via the back guide monitor screen. is there. In Patent Document 1 and the like, an expected trajectory for the vehicle to move is displayed on the back guide monitor screen. However, a position such as a sense of distance to an obstacle such as a wheel stop or the width of the own vehicle with respect to a parking lot. It is still difficult to grasp the relationship from the screen.
An object of the present invention is to provide a parking assist device that can more intuitively grasp the position and posture of a vehicle with respect to a parking position in a back guide monitor.

The present invention for solving the above problems has the following configuration.
(1) imaging means for capturing an image of the rear of the vehicle;
A display device;
A parking position input means for inputting a parked car position,
Distance calculating means for calculating a distance from the host vehicle to the input parking position;
Storage means for storing an outline diagram of the vehicle;
Trajectory calculation means for calculating an expected trajectory from the own vehicle position to the input parking position;
And displays on the display device by superimposing the contour diagram of the computed predicted locus and the previous SL wheel both in the captured image, the displayed contour diagram, apart a predetermined distance from the vehicle position Superimposed display means displayed on
Determining means for determining whether the distance from the current position of the vehicle to the parking position has reached the certain distance;
If the determination means determines that the distance has been reached, the depth of the contour map of the vehicle to be displayed is set to be smaller as the distance calculated by the distance calculation means becomes shorter . A parking assist device comprising: depth setting means for changing the distance.

(2) and a obstacle detection means for detecting whether there is an obstacle present on the calculated pre So軌 traces in the locus calculating means,
The parking assistance apparatus according to (1), wherein when the obstacle detection unit detects the presence of an obstacle, the outline diagram of the vehicle is superimposed in front of the detected obstacle. .

(3) pre-Symbol distance according to the distance calculated by the calculation means, the parking assist apparatus according to the above (1), characterized in that to determine the position of superimposing the contour diagram of the vehicle.
(4) The parking assistance device according to any one of (1) to (3), wherein the parking position input unit inputs a parking position based on the captured image displayed on the display device.

According to the invention described in claim 1, on the screen, because the contour of the actual vehicle is displayed, the vehicle width, etc. with respect to the position and posture and parking width of the vehicle when the backward for parking It becomes easy to grasp on the screen.
According to the second aspect of the present invention, since the vehicle outline diagram when parking is completed is displayed in front of the obstacle, the vehicle can be parked at an appropriate position without contacting the obstacle.
According to the third aspect of the present invention, the position at which the vehicle outline is displayed changes depending on the position where parking is desired. Therefore, when the vehicle is advanced toward the parking position, the vehicle is in a parking position or parked. This makes it easier to grasp the image and makes vehicle steering easier.
According to invention of Claim 4, a camera image is displayed on the display screen of a display apparatus, and a driver | operator inputs a parking position based on the displayed screen. That is, the position where the driver wants to park is designated as the parking position from the image displayed on the screen.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of a parking assistance apparatus 1 according to the present invention. The parking assist device 1 includes an arithmetic processing device 12 that performs image processing, arithmetic processing, and the like, a camera 13 as an imaging unit attached to the rear part of the vehicle body, a host vehicle position detection device 11, and a display unit that displays an image. A display device 14, a storage device 16 as a storage means for images and the like, a steering angle detection sensor 15, an input device 18, and an obstacle sensor 19 are provided, and these devices are mutually connected via a system bus 17. It is connected.

  FIG. 2 is an overhead view showing the positional relationship between the parking position and the vehicle. As shown in FIG. 2, the camera 13 that functions as an imaging unit is rearward in this embodiment so that the optical axis of the lens coincides with the center line of the vehicle at the center of the rear end of the vehicle. It is arranged toward. The camera 13 may use a wide-angle lens. When a wide-angle lens is used, more image information behind the vehicle can be acquired. The camera 13 is connected to the system bus 17 via the A / D converter 131. The image signal output from the camera 13 is converted into a digital signal by the A / D converter 131 for image processing. Further, when the connected camera 13 is capable of outputting a digital signal, the A / D converter 131 is not necessary. For example, a CCD element or a CMOS element is used for the camera 13, and an image is acquired as an electric signal.

The display device 14 as a display means is configured by a liquid crystal display, for example, and displays a composite image stored in the display image data memory 166. If necessary, the display device 14 performs D / A conversion and outputs an image to the screen.
The steering angle detection sensor 15 is a sensor for detecting a steering angle for detecting the moving direction of the vehicle.

  The input device 18 is used to input an activation switch or a parking position of the parking assistance device 1 and is configured by a transparent touch panel sensor plate that is attached to the surface of the display screen of the display device 14 in an overlapping manner. By touching the screen surface with a finger within a range that overlaps the area displayed on the display screen, the touch panel sensor plate detects pressure and identifies the sensing position, and on / off sensing according to the sensing position. I do.

  The obstacle sensor 19 as an obstacle detection means is a sensor that detects an obstacle located behind the vehicle and measures a distance from the vehicle to the obstacle. The obstacle sensor 19 includes, for example, an ultrasonic transmission device and an ultrasonic reception device, receives ultrasonic waves transmitted from the ultrasonic transmission device and reflected back to the obstacle, And measure the distance to the obstacle.

  The own vehicle position detection device 11 uses, for example, a GPS device as a device that detects the absolute position of the own vehicle, and measures a movement distance as a device that detects a relative position from the measurement start position (started point). A moving distance sensor, a geomagnetic sensor for detecting the direction of the vehicle, and other gyro sensors can be used. With this device, the relative positional relationship between the vehicle position and the parking position (target position) can be detected (distance detection means). That is, the distance between the current position and the parking position, and in what direction the parking position is located with the current position as a reference point. Moreover, an ABS pulse sensor etc. can be used for a movement distance sensor, for example. The detection value of the vehicle position detection device 11 is supplied to the arithmetic processing device 12 via the system bus 17.

  The storage device 16 is a device that mainly stores images, and includes, for example, a hard disk drive device or a memory chip. The storage device 16 includes an image data memory 16A that records image data, and a calculated trajectory data memory 16B that stores calculated expected trajectory data. The image data memory 16A is a camera image data memory 161 that directly records an image acquired by the camera 13, contour image data 162 that stores three-dimensional contour map data indicating a vehicle body contour diagram of the vehicle, and a vehicle and a parking position. Contour conversion image data memory 164 that stores an image obtained by performing image processing on the three-dimensional contour data according to the positional relationship, an image converted into an image when viewed from the current position when it is assumed that the vehicle is parked at the parking position Parking position contour image data memory 165 is stored. The contour image data memory 162 functions as storage means in the present invention.

  The arithmetic processing unit 12 includes a central processing unit [CPU (Central Processing Unit)] 121, a read-only memory [ROM] 122, and a random access memory [RAM] 123. The central processing unit 121 superimposes a three-dimensional image indicating a vehicle contour diagram on the image acquired by the camera 13, and changes the position, direction, and size of the three-dimensional image data indicating the vehicle contour. A process for converting to an image, a process for calculating an expected trajectory from the current position to the parking position, a contact determination process for the virtual vehicle 21 and the obstacle, and the like are performed.

The operation of the parking assistance apparatus 1 of the present invention configured as described above will be described based on the flowchart shown in FIG.
The arithmetic processing unit 12 performs initialization based on the start switch of the apparatus being turned on from the input device 18 (step S101). Initialization includes operations such as resetting the current position of the host vehicle determined at the previous use to a reference position. Moreover, it is good also as a structure which starts not only when an activation switch is turned on but when a shift lever is put in the back.

  Imaging is started by the camera 13 (step S103). The captured image is recorded in the camera image data memory 161. At the same time, the camera image is displayed on the display screen of the display device 14 (step S105). Based on the displayed screen, the driver inputs the parking position P0 (step S107). That is, the position where the driver wants to park is designated as the parking position from the image displayed on the screen. The designation of this position is performed by touching the position where the vehicle is parked in the image behind the vehicle displayed on the screen. As a result, the touch panel sensor plate provided on the screen detects the position touched by the finger. Since the camera 13 is fixed to the vehicle, the relative position from the magnification and the angle of view of the image displayed on the screen to the position information corresponding to the position where the finger touches the screen, that is, the parking position input from the own vehicle. The effective distance can be calculated. That is, the direction from the current vehicle position P1 to the parking position P0 and the distance can be calculated by the touch position on the screen (distance calculation means). A parking position input means is comprised by step S107.

  Next, the steering angle of the host vehicle is acquired from the steering angle detection sensor 15 (step S109). Expected trajectories 31 and 32 for displaying the moving trajectory when the vehicle is moved backward at the rudder angle from the parking position P0 input in step S107 and the rudder angle acquired in step S109. Is calculated (step S111). A known method is used as a method for calculating the expected trajectory. The calculated expected trajectory is stored in the calculation trajectory data memory 16B. Step S111 constitutes a locus calculation means.

  The positional relationship between the parking position P0 and the current vehicle position P1 is defined by a direction from the vehicle position P1 toward the parking position P0 and a linear distance connecting the parking position P0 and the current vehicle position P1. For example, the parking position P 0 is set at a position 5 m away from the vehicle position P 1 in the direction of 30 ° to the right from the center line of the vehicle passing through the installation position of the camera 13. Then, a movement predicted trajectory between the set parking position P0 and the current vehicle position P1 is calculated. As the expected trajectory, the expected trajectories of the left and right rear wheels are calculated. In addition, the predicted trajectory of the left and right front wheels may be calculated. Alternatively, predicted trajectories of the left and right front and rear wheels may be calculated. Alternatively, an expected trajectory of the center of gravity of the vehicle may be calculated.

  Next, the three-dimensional contour diagram data of the vehicle is read from the contour image data memory 162 (step S113). In this embodiment, the three-dimensional data of the vehicle is a wire frame that three-dimensionally represents the vehicle contour, and is data relating to an image representing the contour of the vehicle body, windows, headlights, tail lamps, wheels, and the like with lines. The virtual vehicle 21 represented by the contour image is not limited to a wire frame, and may be a translucent vehicle image. That is, it is preferable that the contour image is such that when the vehicle images are superimposed, the rear image overlapping the vehicle can be seen. This is because it becomes easy to grasp the positional relationship with an obstacle described later.

  Next, arithmetic processing is performed (step S115). FIG. 4 is a flowchart showing the contents of the arithmetic processing. An obstacle is detected by the obstacle sensor 19 (step S201). The position of the obstacle may be detected by image processing from information from the captured image. Examples of the obstacle include a bag, a wheel stopper, and other vehicles. Step S201 constitutes an obstacle detection means.

  When an obstacle is detected, it is determined from the position and distance of the obstacle acquired in step S201 if the vehicle moves on the expected trajectories 31 and 32, whether or not the obstacle is touched (step S203). The contact determination is performed based on, for example, whether or not the obstacle 4 is located on the predicted trajectory (on the predicted trajectories 31 and 32 or between the predicted trajectories 31 and 32). Further, when the trajectories of the left and right wheels are obtained, even when a part of the obstacle 4 is in contact with either one of the left and right expected trajectories 31 (32) Is determined.

  If it is determined that they are in contact with each other, the display position of the virtual vehicle 21 represented by the outline diagram is determined to be a position before the obstacle 4 detected in step S201 (step S205). This is to prevent contact with the obstacle 4 during reverse travel. Therefore, this step S205 is determined with priority over the designated parking position P0.

  Furthermore, the direction of the virtual vehicle 21 is determined based on the expected trajectories 31 and 32 (step S207). That is, the orientation of the virtual vehicle 21 is determined so that the center line of the virtual vehicle 21 is positioned along the expected trajectories 31 and 32. The data of the virtual vehicle 21 determined in this way is stored in the contour conversion image data memory 164.

  Next, the distance between the vehicle and the determined parking position is determined, and the size of the virtual vehicle 21 in the screen is determined based on the distance. If the distance is long, it is small, and if it is short, it is displayed large. Thus, the contour data finally superimposed on the image is stored in the parking position contour image data memory 165.

The three-dimensional data of the vehicle 2 stored in the parking position contour image data memory 162 is combined with an image (step S117). The synthesized image is stored in the display image data memory 166 and displayed on the display device 14 (step S119). FIG. 5 is a plan view of the display screen 141 in a state where an image is displayed. At the parking position P0, a contour image of the virtual vehicle 21 by the wire frame is displayed, and the expected trajectories 31 and 32 of the rear wheels are displayed. Steps S117 and S119 constitute superimposing display means.
If the parking position P0 is not designated in step S107, an expected trajectory can be calculated based on the steering angle acquired in step S109, and the parking position is determined in step S205.

  Next, the effect | action of the parking assistance apparatus 1 of 2nd Embodiment is demonstrated based on the flowchart shown by FIG. The arithmetic processing unit 12 reads and initializes the initial value based on the activation switch of the apparatus being turned on from the input device 18 (step S301). The reading of the initial value includes, for example, selection of a vehicle contour image to be displayed. It is possible to select whether to display the contour image of the entire vehicle or only the contour image of the rear part of the vehicle. In this embodiment, as shown in FIG. 7, there are three images: the entire vehicle body image, the rear half image as shown in FIG. 8, and the rear end image as shown in FIG. It can be selected by the input device 18. The selection of such an image can be automatically changed according to the distance between the parking position and the current position of the vehicle. For example, as the distance becomes shorter, the depth of the displayed image is also set smaller. Specifically, when the distance to the parking position is longer than the full length L of the vehicle, the whole image is shorter than the full length, and when the distance is shorter than half the full length, the rear half image is shorter than the full length half. If it is, the image is switched to the rear end image.

  The initialization includes an operation such as resetting the current position to the reference position in the vehicle position detection device 11. Moreover, it is good also as a structure which starts not only when an activation switch is turned on but when a shift lever is put in the back.

  Imaging is started by the camera 13 (step S303). The image is recorded in the camera image data memory 161. At the same time, the camera image is displayed on the screen of the display device 14 (step S305). Based on the displayed screen, the driver inputs the parking position P0 (step S307). That is, the position where the driver wants to park is designated as the parking position from the image displayed on the screen. Since this designation method is the same as step S107 in the previous embodiment, the description thereof is omitted. As shown in FIG. 10, the positional relationship between the parking position P0 and the current position P1 of the vehicle is specified.

Next, parking support processing (step S309) is performed. FIG. 11 is a flowchart showing the contents of the parking support process. An image behind the vehicle is acquired from the camera 13 (step S401), and the steering angle is detected by the steering angle detection sensor 15 (step S403). An expected trajectory from the current position P1 to the parking position P0 is calculated from the parking position P0 and the steering angle acquired in step S307 (step S405). This expected trajectory is a trajectory of the left and right rear wheels. The calculation method and the content of the trajectory are the same as the content of step S111 in the embodiment.
Next, the vehicle three-dimensional data is read from the contour image data memory 162 as in step S113 of the previous embodiment (step S407).

  Next, calculation processing for setting the display position of the virtual vehicle image is performed (step S409). FIG. 12 is a flowchart showing the contents of the arithmetic processing. In the calculation process, the distance between the vehicle position P1 and the parking position P0 is calculated (step S501). This distance is calculated by subtracting the distance traveled by the vehicle from the distance to the parking position P0 calculated when the parking position P0 is initially set. The travel distance of the vehicle is obtained from the vehicle position detection device 11. This step S501 constitutes a distance calculation means.

  The contour image of the virtual vehicle displayed on the screen of the display device 14 is composed of a wire frame, and the content is set in advance as described above in the description of the initial value setting (step S301). . And in the display screen 141, it sets so that a virtual vehicle may be located in the position where the vehicle was separated from the fixed distance X.

  When the vehicle moves backward and approaches the parking position P0, the virtual vehicle first reaches the parking position P0. Therefore, it is determined whether the distance from the current position P1 of the vehicle to the parking position P0 has reached the distance X (step S503). If it has arrived, the position of the virtual vehicle 211 is fixed on the parking position P0 (step S505). Since the position of the virtual vehicle 211 is fixed, the distance X between the vehicle 2 and the virtual vehicle 211 becomes shorter as the vehicle 2 moves backward. Therefore, it is determined whether the distance X is shorter than the total length of the vehicle (step S507). If it is shorter, the virtual vehicle is changed to the rear half virtual vehicle 212 (step S509). Further, it is further determined whether or not the distance X is shorter than half the total vehicle length (step S507). If the distance X is shorter, the contour image 213 at the rear end of the vehicle is changed (step S509). Thus, the display content is changed according to the distance to the parking position P0.

  The contour image of the virtual vehicle thus determined is combined with the camera image (step S411) and displayed on the display screen 141 of the display device 14 (step S413). As shown in FIG. 13, predicted trajectories 31 and 32 and a three-dimensional contour image 211 are displayed on the display screen 141.

It is determined whether there has been a parking assistance end trigger (step S415). If not, the process returns to step S401 and repeats the process up to step S415. If there is an end trigger, the parking support routine is ended. Examples of the end trigger include setting the shift lever to a position other than the parking position, and turning off the ignition.
Thus, when the vehicle moves backward and the virtual vehicle is fixed at the parking position, the content of the virtual vehicle (contour image) displayed on the display screen changes as the vehicle approaches the parking position, and finally The movement to the parking position is completed at the position where the rear part of the vehicle 2 and the rear part of the virtual vehicle 213 overlap.

It is a block diagram which shows the structure of a parking assistance apparatus. It is an overhead view which shows the positional relationship of a parking position and a vehicle. It is a flowchart which shows an effect | action of a parking assistance apparatus. It is a flowchart which shows the content of the arithmetic processing. It is a top view which shows the content of the image displayed on the display screen. It is a flowchart of other embodiment. It is a top view which shows the display content of the outline image by the positional relationship of a vehicle and a virtual vehicle. It is a top view which shows the display content of the outline image by the positional relationship of a vehicle and a virtual vehicle. It is a top view which shows the display content of the outline image by the positional relationship of a vehicle and a virtual vehicle. It is an overhead view which shows the positional relationship of a parking position and a vehicle. It is a flowchart which shows the parking assistance process content. It is a flowchart which shows the content of the arithmetic processing of other embodiment. It is a top view which shows the content of the image displayed on the display screen.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Parking assistance apparatus 12 Arithmetic processing apparatus 13 Camera 14 Display apparatus 16 Memory | storage device 21 Virtual vehicle (contour image)
31, 32 Expected locus P0 Parking position

Claims (4)

Imaging means for capturing an image of the rear of the vehicle;
A display device;
A parking position input means for inputting a parked car position,
Distance calculating means for calculating a distance from the host vehicle to the input parking position;
Storage means for storing an outline diagram of the vehicle;
Trajectory calculation means for calculating an expected trajectory from the own vehicle position to the input parking position;
And displays on the display device by superimposing the contour diagram of the computed predicted locus and the previous SL wheel both in the captured image, the displayed contour diagram, apart a predetermined distance from the vehicle position Superimposed display means displayed on
Determining means for determining whether the distance from the current position of the vehicle to the parking position has reached the certain distance;
If the determination means determines that the distance has been reached, the depth of the contour map of the vehicle to be displayed is set to be smaller as the distance calculated by the distance calculation means becomes shorter . A parking assist device comprising: depth setting means for changing the distance. Obstacle detection means for detecting whether there is an obstacle present on the expected trajectory calculated by the trajectory calculation means,
The parking assistance device according to claim 1, wherein when an obstacle is detected by the obstacle detection unit, an outline diagram of the vehicle is superimposed in front of the detected obstacle. It said distance calculated according to the distance calculated by means parking assist apparatus according to claim 1, characterized in that to determine the position of superimposing the contour diagram of the vehicle. The parking assistance device according to any one of claims 1 to 3, wherein the parking position input means inputs a parking position based on the captured image displayed on the display device.

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