JP2009220592A - On-vehicle parallel parking assistant device and program for on-vehicle parallel parking assistant device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To display an image such that possibility of contact between a vehicle and an obstacle can be more clearly grasped, in technology for assisting parallel parking of the vehicle to a rear side of the obstacle. <P>SOLUTION: The on-vehicle parallel parking assistant device mounted on the vehicle 1 specifies a contact caution position near a corner 2a of the vehicle 2 present at a front side of a parallel parking space and specifies the optimum visual point 4 for photographing the specified contact caution position. When an outdoor photographing camera reaches to the specified visual point position 4, the contact caution point and its periphery are photographed by the camera, and they are recorded making it as the optimum visual point image. Further, the on-vehicle parallel parking assistant device repeatedly superimposes one's own vehicle image reflecting the present attitude and position of the vehicle 1 relative to the optimum visual point image at the cut-back stage and successively displays a synthesis image 31 of the superimposition result. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle-mounted parallel parking support device and a vehicle-mounted parallel parking support device program.

  Conventionally, when a vehicle is parked in parallel behind an obstacle such as a forward vehicle, an apparatus that supports the parallel parking is known. For example, a technique is known in which the distance between an obstacle and the host vehicle is measured using an ultrasonic sonar, and a warning sound is changed according to the measured distance.

  Further, in Patent Document 1, an in-vehicle camera is used to photograph a portion between an obstacle and the host vehicle, and by using the photographed result, the obstacle passes through the bonnet portion of the host vehicle as if the obstacle is transmitted. Techniques for projecting visible images are described.

Patent Document 3 describes a technique for displaying a bird's-eye view of the host vehicle and its surroundings viewed from above using an image displayed around the host vehicle captured by an in-vehicle camera on an image display device in the vehicle. Has been.
JP 2006-248384 A JP 2007-148761 A

  However, as described above, the technology using ultrasonic sonar can grasp the distance between the obstacle and the own vehicle to some extent, but whether or not the vehicle touches the obstacle in the current maneuvering. It is difficult to judge.

  Further, in the technique such as Patent Document 1, although the position of the obstacle can be visually observed, since the displayed image is only the viewpoint of the position of the driver, the distance relationship between the front end portion of the own vehicle and the obstacle It is difficult to grasp.

  Moreover, in the technique like patent document 2, the image which is easy to grasp | ascertain visually the distance between the front-end part of the own vehicle and an obstruction is displayed. However, the bird's-eye view image does not include much information for supporting parallel parking.

  In the case of parallel parking from the right side, for example, when parking in parallel from the right side, the corners at the left front end of the vehicle and the right rear end corner of the obstacle are high. The bird's-eye view image displays the corner at the right rear end of the obstacle as one point. Accordingly, as illustrated in FIG. 17 as a reference example (not the prior art itself), when the right rear end corner of the obstacle 81 in front of the vehicle 80 does not rise vertically (for example, the rear end portion of the truck). The displayed bird's-eye view may not accurately reflect the right rear end of the obstacle 81.

  In fact, in the example of FIG. 17, when the image captured by the in-vehicle camera 83 is converted into the bird's-eye view 92, the vehicle in the bird's-eye view 92 has the image 90 and the obstacle image 91 because the lower part of the obstacle 82 is recessed. The distance A may be longer than the actual shortest distance B.

  In view of the above points, the present invention provides an image display that can more clearly grasp the possibility of contact between the vehicle and the obstacle in the technology for supporting the parallel parking of the vehicle behind the obstacle. Objective.

  In order to achieve the above object, the invention according to claim 1 is mounted on a vehicle (1) equipped with a camera outside the vehicle (10), and is located behind the obstacle (2) from the first side of the vehicle (1). This relates to an in-vehicle parallel parking support device that supports parallel parking.

  This in-vehicle parallel parking assist device is configured so that the second side of the vehicle (1) at the turnover stage that will come later in parallel parking (on the opposite side of the first side, that is, on the left side if the first side is the right side, Identify the attention position (2d, 53, 56) between the front end (1a) on the right side if the 1 side is the left side and the rear end (2a) on the first side of the obstacle (2), A viewpoint position (20, 55, 62) for photographing the specified attention position (2d, 53, 56) in advance is specified.

  Further, the in-vehicle parallel parking assistance device displays the attention position (2d, 53, 56) and the surrounding captured image (30) taken by the outside camera (10) at the specified viewpoint position (20, 55, 62). Acquired, and in the switching stage, the own vehicle image (40) reflecting the current posture and position of the vehicle (1) is superimposed on the photographed image (30), and the resultant composite image (31) is superimposed. The image is displayed on the image display device (12) in the vehicle (1).

  Here, the viewpoint position (20, 55, 62) is on the first side and in front of the attention position (2d, 53, 56).

  In this way, the image displayed on the driver is at the caution position (2d) from the viewpoint that the first side and the front of the caution position (2d, 53, 56) can easily determine whether the vehicle is in contact with the obstacle. 53, 56), the user can clearly grasp the distance between the vehicle (1) and the obstacle (2). Moreover, the image which looked at the attention position (2d, 53, 56) from such a viewpoint is different from the bird's-eye view, and the front end (1a) on the second side of the vehicle (1) and the second of the obstacle (2). 1 includes information on the shape of the rear end portion (2a) on the 1 side in the vertical direction. Therefore, the driver can grasp the distance between the vehicle (1) and the obstacle (2) more accurately.

  Further, as described in claim 2, the in-vehicle parallel parking assist device may specify the viewpoint position (20) as a position unrelated to the position of the vehicle (1). By doing so, the processing content for specifying the viewpoint position (20) is simplified.

  According to a third aspect of the present invention, the in-vehicle parallel parking assist device is configured to predict the movement trajectory (50) of the front end portion (1a) on the second side of the vehicle (1) that is expected for the turning-back stage of the vehicle (1). The viewpoint position (55, 62) may be determined based on the position of). In this way, the viewpoint position (55, 62) that more closely matches the behavior of the vehicle (1) during parallel parking can be specified.

  Further, as described in claim 4, the in-vehicle parallel parking assist device is configured to determine the viewpoint position based on the predicted position of the movement locus (50) and the position of the rear end (2 a) of the obstacle (2). (55) may be determined. In this way, it is possible to specify a more appropriate viewpoint position (55, 62) corresponding to the behavior of the vehicle (1) when parallel parking and the positional relationship between the obstacle (2).

  In addition, as described in claim 5, the in-vehicle parallel parking assistance device includes a plurality of images that have been repeatedly photographed by the outside-camera camera (10) when the vehicle (1) is moving forward immediately before parallel parking. The captured image (30) may be acquired by extracting from the image.

  Thus, using the fact that the outside-camera camera (10) may pass through the viewpoint position (55, 62) when the vehicle moves forward as the preceding stage of parallel parking, the attention position (2d, By capturing 53, 56), it is possible to easily obtain an image in which the attention position (2d, 53, 56) is captured from the viewpoint position (55, 62).

  Further, as described in claim 6, the features of the present invention can also be understood as a program.

  In addition, the code | symbol in the bracket | parenthesis in the said and the claim shows the correspondence of the term described in the claim, and the concrete thing etc. which illustrate the said term described in embodiment mentioned later. .

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described. FIG. 1 illustrates an example of a scene to which this embodiment is applied. In this figure, the vehicle 1 is about to be parked in parallel in an empty space between the vehicle (corresponding to an example of an obstacle) 2 and the vehicle 3. As shown in this figure, when parking in parallel from the right side (corresponding to an example of the first side) in the space behind the front vehicle 2, the driver of the vehicle 1 usually arranges the vehicle 1 on the right side of the front vehicle 2. Then, turn the steering wheel to the left and move backward, and then turn the steering wheel to the right and keep moving backward until parallel parking is completed.

  Hereinafter, in such a parallel parking stage, the stage from the time when the steering is turned to the left and the vehicle starts to reverse to the time when the steering is turned to the right is referred to as “beginning of turning”. In addition, the stage from turning the steering wheel to the left after the stage of starting the turn until the end of the parallel parking is referred to as a “turn-back stage”.

  In such a normal parallel parking turn-back stage, the vehicle 1 and the front vehicle 2 are likely to come into contact with each other because the left front end of the host vehicle (corresponding to an example of the front end on the second side) 1a and the front vehicle This is the position of the right rear end portion (corresponding to an example of the rear end portion on the first side) 2a. The optimal position as a viewpoint for visually grasping the distance between the two points 1a and 2a is a viewpoint position viewed from the direction indicated by the arrow 4, that is, the position between the two points 1a and 2a. This is the right front position. This position is a position where the two points 1a and 2a can be seen without being blocked by the vehicle bodies of the vehicle 1 and the forward vehicle 2, and the difference between the two points 1a and 2a can be seen from the front.

  The parallel parking support system of the present embodiment is mounted on the vehicle 1, and after the parallel parking of the vehicle 1 is switched back, the vehicle left front end 1 a and the front vehicle right rear end 2 a are viewed in the line-of-sight direction as indicated by the arrow 4. By providing a real-time image when viewed to the driver of the vehicle 1, parallel parking of the vehicle 1 is supported.

  In FIG. 2, the structure of the parallel parking assistance system 99 which concerns on this embodiment is shown. The parallel parking assist system 99 includes an outside camera 10, a position detector 11, an image display device 12, an operation unit 13, a distance measuring sensor 14, a steering sensor 15, a storage medium 16, and a control circuit 17.

  The outside camera 10 is a wide angle camera provided on the right side, left side, and rear side of the vehicle 1. Each of these cameras can photograph a wide angle (for example, 130 ° to 180 °) around the right direction, the left direction, and the back direction of the vehicle 1 as viewed from the vehicle 1 at a time. Further, the outside-camera shooting camera 10 sequentially outputs the captured images to the control circuit 17.

  The position detector 11 includes devices such as a vehicle speed sensor, an acceleration sensor, a gyro sensor, a geomagnetic sensor, and a GPS receiver. The position detector 11 detects physical quantities of the position, movement speed, posture, and turning angular velocity of the vehicle 1 and supplies the control circuit 17 with the physical quantities. Output sequentially.

  The image display device 12 displays a video based on the video signal output from the control circuit 17 to the user. The operation unit 13 includes an input device such as a mechanical switch and a touch panel provided on the display surface of the image display device 12, and outputs a signal based on pressing of the mechanical switch by the driver and touch on the touch panel to the control circuit 17. .

  The distance measuring sensor 14 is a device that detects the direction from the vehicle 1 and the distance from the vehicle 1 and sequentially outputs them to the control circuit 17 for objects around the vehicle 1. As the distance measuring sensor 14, for example, an ultrasonic sonar, a laser radar, a millimeter wave radar, a stereo camera, or the like can be used.

  The steering sensor 15 is a device that detects the turning angle of the steering by the driver and outputs it to the sequential control circuit 17.

  The storage medium 16 is a writable nonvolatile storage medium such as an HDD or a flash memory. The storage medium 16 records data such as a program to be executed by the control circuit 17. The storage medium 16 stores three-dimensional data of the outer shape of the vehicle 1, information about the installation position of the outside-camera shooting camera 10 on the vehicle 1, and the shooting range of the outside-camera shooting camera 10.

  A control circuit (corresponding to an example of an in-vehicle parallel parking support apparatus and an example of a computer) 17 is a microcomputer having a CPU, a RAM, a ROM, an I / O, and the like. The CPU executes the program read from the ROM or the storage medium 16, reads information from the RAM, the ROM, and the storage medium 16 when executing the program, and sends information to the RAM and the storage medium 16 (if possible). , And exchanges signals with the outside camera 10, the position detector 11, the image display device 12, the operation unit 13, the distance measuring sensor 14, and the steering sensor 15.

  A specific process performed by the control circuit 17 executing the program is a parallel parking support process. When the driver tries to park the host vehicle 1 behind an obstacle such as a preceding vehicle, the control circuit 17 executes a parallel parking support process. An image is displayed on the image display device 12 so that the distance between them can be easily determined.

  FIG. 3 shows a flowchart of the program 100 executed by the control circuit 17 for the parallel parking support process. The control circuit 17 may start the execution of the program 100 based on the driver performing an operation indicating the start of parallel parking on the operation unit 13, or that the ignition switch of the vehicle 1 is turned on. The execution of the program 100 may be started based on the fact that the moving speed of the vehicle 1 specified based on the signal from the position detector 11 is equal to or lower than the reference speed (for example, 10 km / h). Execution may begin.

  Hereinafter, as shown in FIG. 1, the case where the vehicle 1 is parked in parallel from the right side behind the front vehicle 2 as a front obstacle (and in front of the rear vehicle 3 as a rear obstacle) is taken as an example. An execution process of the program 100 of the control circuit 17 will be described. The following description is applicable not only to parallel parking from the right side but also to parallel parking from the left side. However, in that case, it is necessary to replace the right in the following description with the left and the left with the right.

  In the execution of the program 100, the control circuit 17 first acquires an optimal viewpoint image (corresponding to an example of a photographed image) in step 110, subsequently performs a cut-back determination in step 120, and then continues in step 130. Then, in step 140, display image generation and display control on the image display device 12 are performed. Then, in step 150, it is determined whether or not the parallel parking support process is to be ended. If it is determined to be ended, the execution of the program 100 is ended. If not, steps 130 and 140 are repeated.

  Here, in step 150, it may be determined that the driver has completed the operation indicating that the parallel parking has been ended with respect to the operation unit 13, or may be determined to be ended, or based on the ignition switch of the vehicle 1 being turned off. May be determined to end.

  The optimal viewpoint image is a viewpoint position suitable for visually recognizing the distance between the left front end 1a of the host vehicle 1 and the right rear end 2a of the forward vehicle 2 that are most likely to come into contact at the turn-back stage of parallel parking. It is the image which the vehicle outside camera 10 image | photographed the position (equivalent to a caution position) between the said site | parts 1a and 2a and its periphery.

  Further, the turn-back determination is a process for determining that the vehicle 1 has finished the turn-start stage and entered the turn-back stage in parallel parking. The own vehicle image is an image of the own vehicle 1 to be superimposed on the optimum viewpoint image. The display image is a composite image obtained by superimposing the host vehicle image on the optimum viewpoint image.

  First, the processing content of the optimum viewpoint image acquisition in step 110 will be described in detail. The control circuit 17 executes the flowchart shown in FIG. 4 for the optimum viewpoint image acquisition process. In this execution, the control circuit 17 first detects a parallel parking space in step 112. The parallel parking space is detected based on a signal from the distance measuring sensor 14. That is, the position of the obstacles 2 and 3 around the vehicle 1 with respect to the vehicle 1 is specified using the signal from the distance measuring sensor 14, and the obstacle 2 (the vehicle body of the vehicle 1 is determined based on the specification result. A space that is large enough to allow the vehicle 1 to park is searched behind.

  It should be noted that the timing at which the parallel parking space is detected in step 112 is almost always the case where the vehicle 1 is moving forward at the low speed at the side of the parallel parking space as the previous stage of parallel parking.

  Subsequently, in step 114, the contact attention corner (corresponding to an example of the attention position) of the obstacle 2 immediately in front of the detected parallel parking space (based on the front-rear direction of the vehicle body of the vehicle 1) is specified. As shown in FIG. 5, the contact attention corner is specified as a position 2d where the line 2b on the right side surface of the forward vehicle 2 and the line 2c at the rear end are orthogonal to each other. The contact caution corner 2d coincides with the position of the front vehicle right rear end 2a of the front vehicle 2 shown in FIG. 1, or is positioned slightly rearward from the front vehicle right rear end 2a.

  Subsequently, in step 116, an optimal viewpoint position for the contact attention corner 2d is specified. As shown by the arrow line 20 in FIG. 5, the optimum position is specified as a linear point group having the contact attention corner 2d as an end point in the horizontal plane. The inclination angle θ of the straight line formed by the optimal viewpoint position 20 with respect to the line 2b may be a predetermined constant value (for example, 45 °), or may change according to a setting operation using the operation unit 13 by the driver. It may be.

  However, in the optimum viewpoint position 20, the distance between the contact caution corner 2d and the host vehicle left front end 1a is easy to see, and the contact caution corner 2d and the host vehicle left front end 1a are blocked by the vehicle 1 and the front vehicle 2. This is a safe position. Therefore, the optimal viewpoint position 20 needs to be located forward and to the right when viewed from the contact attention corner 2d. That is, the inclination angle θ needs to be larger than 0 ° and smaller than 90 °. Therefore, the control circuit 17 may accept only the setting by the driver of the angle within this range, and ignore the setting exceeding this range.

  Subsequently, in step 118, the position of the camera provided on the left side of the vehicle 1 (or the camera provided on the rear) of the outside-camera shooting camera 10 in the horizontal plane reaches one of the optimum viewpoint positions 20. Step 119 is executed subsequently. The position of the optimal viewpoint position 20 is based on the current position and posture information of the vehicle 1 acquired from the position detector 11 and the installation position information on the vehicle 1 of the outside-camera camera 10 read from the storage medium 16. Identify.

  In step 119, the camera that has reached the optimum viewpoint position 20 is caused to take a picture, and an image of the result of the photography is acquired and recorded in the storage medium 16. Hereinafter, the camera that has taken an image at the optimum viewpoint position 20 in step 119 is referred to as an imaging camera.

  As described above, since the outside camera 10 is a wide-angle camera, if the vehicle 1 stays within the normal posture range for parallel parking, the image taken at the optimum viewpoint position 20 is the contact attention corner 2d and its Includes images of surrounding locations. This acquired image becomes the optimum viewpoint image. FIG. 6 shows an example of the optimal viewpoint image 30. As shown in this figure, the optimal viewpoint image 30 includes images of the right rear end 2 a of the rear vehicle 3 and the front vehicle 2. After step 119, the optimum viewpoint image acquisition process (step 110) ends.

  Next, the switching determination in step 120 will be described in detail. In this switching determination, the control circuit 17 executes a flowchart as shown in FIG. 7. In this execution, first, in step 122, whether or not the driver of the vehicle 1 has entered the switching start stage is determined from the steering sensor 15. Determine based on the signal.

  Specifically, if the steering angle obtained from the steering sensor 15 is greater than or equal to the first reference angle to the left, it is determined that the vehicle has entered the stage of starting to turn. Here, the first reference angle may be 2/3 of the maximum left turn angle of the steering. For example, the first reference angle may be 360 ° if the steering can be rotated one and a half times to the left from the center position.

  If the turning start stage is entered, then in step 124, the control waits until the steering turning angle changes to the right by the second reference angle or more. If so, it is determined in step 126 that the turning has started, and the turning is performed. The determination is finished and the routine proceeds to step 130 in FIG. Note that the second reference angle is, for example, twice the first reference angle.

  Next, the host vehicle image generation process in step 130 after the switching will be described. In this process, the control circuit 17 executes a flowchart as shown in FIG. 8. In this execution, first, in step 132, the position and posture of the host vehicle 1 are specified based on the signal from the position detector 11.

  Subsequently, in step 134, when the contact caution corner 2d and its surroundings are photographed from the optimal viewpoint image at the present time, calculation is made as to how the own vehicle 1 appears in the photographed image. That is, the current vehicle 1 is calculated in which shape and in which position in the optimum viewpoint image already acquired in step 110 in FIG.

  Specifically, based on the current position and orientation information of the host vehicle 1 specified in the immediately preceding step 132 and the three-dimensional information of the outer shape of the vehicle 1 in the storage medium 16, the current outer shape of the vehicle 1 is 3 Identifying a position range that occupies the dimensional space, and subsequently, based on the identified position range, information on the photographing range of the photographing camera in the storage medium 16, and position information of the photographing camera at the time of photographing the optimum viewpoint image, How the vehicle 1 looks in the optimal viewpoint image is calculated.

  Subsequently, in step 136, a host vehicle image to be superimposed on the optimum viewpoint image is generated based on the information calculated in step 134, and then the host vehicle image generation process (step 130) is ended.

  Next, the display image generation / display control in step 140 will be described. In this processing, the control circuit 17 executes a flowchart as shown in FIG. 9. In this execution, first, in step 141, the arrangement based on the information calculated in step 134 of the immediately preceding FIG. 3 is superimposed on the optimal viewpoint image acquired in step 110 of FIG. FIG. 10 shows an example of the composite image 31 as a result of superimposing the host vehicle image 40 on the optimal viewpoint image. As shown in this figure, in the composite image 31, the distance between the left front end 1a of the host vehicle after turning and the right rear end 2a of the front vehicle can be clearly seen, and the left front end 1a of the host vehicle and the right front of the front vehicle Since the shape of the end 2a along the vertical direction can also be visually recognized, the information for supporting parallel parking is abundant.

  Subsequently, in step 142, it is determined whether or not to perform distortion correction. Specifically, it is determined that distortion correction is performed when the distortion correction flag in the RAM of the control circuit 17 is on, and it is determined that distortion correction is not performed when it is off. The initial value of the distortion correction flag is on, and the value is changed based on a switching operation using the operation unit 13 of the driver. The wide-angle image captured by the outside-camera camera 10 has distortion because it is wide-angle, but depending on the driver, it may be easier to view without correcting the distortion. If distortion correction is to be performed, then step 144 is executed. If not, step 146 is subsequently executed. In step 144, a known distortion correction process is performed on the composite image 31. Subsequent to step 144, step 146 is executed.

  In step 146, whether or not to perform zoom processing is determined based on whether or not the driver has performed an operation to perform zoom processing on the operation unit 13. When the zoom process is performed, subsequently, in step 148, the composite image 31 is enlarged at a magnification according to the operation content of the driver with respect to the operation unit 13. When the zoom process is not performed, and after step 148, in step 149, the composite image 31 subjected to the distortion correction and the zoom process as necessary is displayed on the image display device 12 as a display image. As a result, the driver can check the display image.

  As described above, the control circuit 17 identifies the position of the contact attention corner 2d near the corner of the vehicle 2 in front of the parallel parking space (see step 112) (see step 114), and identifies the identified contact attention corner 2d. The optimal viewpoint position 20 for shooting is identified (step 116), and when the left camera (or rear side) of the outside-camera shooting camera 10 reaches the identified viewpoint position (see step 118), attention is touched with the camera. The corner 2d and its surroundings are photographed and recorded as an optimum viewpoint image in the storage medium 16 for use in a later turn-back stage (see step 119). The contact caution corner 2d is positioned between the left front end 1a of the host vehicle and the right rear end 2a of the front vehicle at the turning-back stage that will come later in parallel parking.

  In this manner, first, the viewpoint position 20 is determined by determining one point (specifically, the contact caution corner 2d) between the left front end 1a of the host vehicle and the right rear end 2a of the forward vehicle and determining the direction with respect to the one point. To do. In this way, the viewpoint position can be easily determined.

  Further, the control circuit 17 uses the optimal viewpoint image 30 previously captured in this manner, and repeatedly repeats the own vehicle image 40 reflecting the current posture and position of the vehicle 1 with respect to the optimal viewpoint image 30 at the switching stage. The superimposed image 31 is displayed on the image display device 12 sequentially in real time (see steps 130, 140, and 150). The optimum viewpoint position 20 is characterized in being on the right side and the front side of the contact attention corner 2d.

  As described above, the image displayed on the driver is an image in which the contact attention corner 2d is viewed from the viewpoint that it is easy to determine whether or not the vehicle 1 and the front vehicle 2 can be contacted, ie, the left front side of the contact attention corner 2d. Therefore, the user can clearly grasp the distance between the vehicle 1 and the obstacle 2. In addition, an image of the contact attention corner 2d viewed from such a viewpoint, unlike the bird's eye view, includes information on the vertical vertical shape of the left front end 1a of the host vehicle and the right rear end 2a of the front vehicle. Therefore, the driver can grasp the distance between the vehicle 1 and the preceding vehicle 2 and the possibility of contact more accurately.

  In addition, the control circuit 17 specifies an approach area where the vehicle 1 is closest to the obstacle 2 at the turn-back stage of the parallel parking (that is, an area around the contact attention corner 2d) before the turn-back stage. The viewpoint position 20 for photographing is specified, and the captured image 30 of the approaching area captured before the switching stage at the viewpoint position 20 by the outside camera 10 is acquired, and in the switching stage, the captured image 30 is displayed on the captured image 30. The host vehicle image 40 reflecting the current posture and position is superimposed, and a composite image 31 as a result of the superposition is displayed on the image display device 12 in the vehicle 1. The viewpoint position 20 is on the right side and in front of one point (that is, the contact attention corner 2d) in the peripheral area.

  Further, the control circuit 17 determines the optimum viewpoint position 20 based only on the position of the front obstacle 2 among the position of the own vehicle 1 and the front obstacle 2, that is, regardless of the position of the own vehicle 1 and the front vehicle. 2 is specified based only on the position 2 and the angle θ. In this way, the specific processing content of the viewpoint position 20 is simplified.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. This embodiment is different from the first embodiment in that the storage medium 16 stores trajectory data described later, the shooting timing by the outside camera 10, and the processing content of step 110 in FIG. 3.

  Specifically, the control circuit 17 specifies the moving distance of the host vehicle based on the signal from the position detector 11 and takes an image outside the vehicle every time the moving distance increases by a first reference distance (for example, 0.1 meter). Each of the cameras 10 performs shooting, and the acquired captured image is additionally recorded in the storage medium 16 together with information on the position of the shooting camera at the time of shooting.

  As described above, the control circuit 17 captures and records the periphery of the vehicle 1 in advance with the outside camera 10. One of these recorded images is used as an optimum viewpoint image in the subsequent parallel parking support process. Therefore, it is necessary that such repeated photographing and repeated recording processes be performed before the vehicle 1 reaches the optimum viewpoint position. For this reason, the control circuit 17 may start such repeated photographing and recording processing based on the ACC of the vehicle 1 being turned on. Alternatively, it may be the time when the parallel parking space detection is started in step 112 of FIG.

  In addition, the control circuit 17 stores a large amount of images before the parallel parking support process is started, and as a result, the storage capacity of the storage medium 16 is prevented from being insufficient. Past captured images that are more than the second reference distance may be discarded from the storage medium 16.

  Here, the second reference distance may be a fixed distance (for example, several meters), or may be determined based on an amount that varies depending on the size of the vehicle 1 (for example, a moving amount necessary for parallel parking). It may be. Further, the second reference distance may be longer as the storage capacity of the storage medium 16 is larger.

  When the host vehicle 1 is stopped, the camera is photographed at predetermined time intervals, and the image of the photographing result is sequentially updated in the storage medium 16 as a photographed image of the current position of the camera at that time. It may be recorded.

  Further, in the process of step 110, the control circuit 17 according to the present embodiment performs steps 112, 114, and 116 of FIG. This is because in the present embodiment, when the optimum viewpoint position is specified in step 116, the host vehicle 1 has already saved the captured image at the optimum viewpoint position in the storage medium 16.

  Hereinafter, the processing content of step 116 in this embodiment is explained in full detail. FIG. 11 shows a flowchart of the processing of step 116. In the execution of the processing of this flowchart, the control circuit 17 first detects the cutting start position at step 210. The detection of the cutting start position waits for the start of cutting in the same manner as in step 122 in FIG.

  Subsequently, at step 220, a moving trajectory at the turn-back stage predicted for the vehicle left front end portion 1a (hereinafter referred to as an expected trajectory) is specified based on the trajectory data in the storage medium 16. Here, the trajectory data recorded in advance in the storage medium 16 (for example, when the vehicle 1 is shipped) will be described.

  The trajectory data includes trajectory data for parallel parking from the right side and parallel parking data from the left side. In the following, only the trajectory data for parallel parking from the right side of the obstacle 2 (hereinafter referred to as right trajectory data) will be described with reference to FIG. The same except for the differences.

  The right trajectory data is created as follows. First, at the initial position V of the vehicle, the steering wheel is turned to the maximum at the left and then moved backward for a while, then at the first halfway point W, the steering wheel is turned back to the maximum at the right side, and the vehicle is moved backward until it faces the same direction as the initial position. In the case of continuing, the trajectory BB ′ (circular arc centered at the point Rb) of the left front end of the vehicle at the turning-back stage is calculated.

  Next, at the initial position V of the vehicle, the steering is turned to the maximum at the left, and the vehicle is moved backward for a while. Then, at the second intermediate point X beyond the first intermediate point W, the steering is turned back to the maximum at the right. A trajectory C-C ′ (circular arc centered at the point Rc) of the vehicle front left end portion at the turn-back stage when the vehicle continues to move backward until it faces the same direction as the position is calculated.

  Next, at the initial position V of the vehicle, the steering is turned to the maximum at the left, and the vehicle is moved backward for a while. Then, at the third halfway point Y beyond the second halfway point X, the steering is turned back to the maximum at the right. A trajectory DD ′ (circular arc centered at the point Rd) of the vehicle front left end at the turn-back stage when the vehicle continues to move backward in the same direction as the position is calculated.

  Furthermore, the relative position with respect to the initial position V of the outer peripheral line L connecting the leftmost of these trajectories BB ′, CC ′, and DD ′ is specified as the right trajectory data. When the steering is turned back to the maximum at the first halfway point W and the vehicle continues to move backward until it faces the same direction as the initial position, the position of the vehicle is shifted to the right by one vehicle from the initial position V. In addition, the first intermediate position is determined. This is because in parallel parking, the vehicle 1 is almost shifted to the left by at least one vehicle. Such trajectory data is uniquely determined if the vehicle structure such as the maximum steering angle and wheelbase is determined.

  In step 220 in FIG. 11, the right trajectory data recorded in advance in this way is read from the storage medium 16. Then, by applying this right trajectory data to the current position of the vehicle 1, as shown in FIG. 13, the expected trajectory 50 of the left front end 1a of the host vehicle with respect to the current road is specified.

  Subsequently, in step 230, as shown in FIG. 14, the contact attention corner 2d is determined in the same manner as in step 114 of FIG. 4 in the first embodiment, and further, the point closest to the contact attention corner 2d in the expected trajectory 50. 51 is specified.

  Subsequently, in step 240, the midpoint (corresponding to an example of the caution position) 52 of the horizontal line segment 55 connecting the specified point 51 and the contact caution corner 2d is specified. Subsequently, in step 250, a portion on the right side of the midpoint 52 in the vertical bisector 55 is set as the optimum viewpoint group, and then the optimum viewpoint position calculation (step 116) is terminated.

  As described above, the control circuit 17 determines the viewpoint position based on the position of the movement trajectory 50 of the left front end 1a of the host vehicle 1 that is expected for the turning-back stage of the vehicle 1. By doing in this way, the viewpoint position 55 which matched the behavior at the time of the parallel parking of the vehicle 1 can be specified more.

  Further, the control circuit 17 determines the viewpoint position based on the predicted position of the movement locus 50 and the position of the contact attention corner 2d. Specifically, from the midpoint 52 of the horizontal bisectors 55 passing through the midpoint 52 of the horizontal line segment connecting the predicted trajectory 50 and the position closest to the contact attention corner 2d. The right part is the viewpoint position.

  In this way, it is possible to specify a more appropriate viewpoint position according to the behavior of the vehicle 1 during parallel parking and the positional relationship of the obstacle 2.

  In step 119 following step 116, the control circuit 17 extracts the image at the optimum viewpoint position identified in step 116 from the photographed image of the left camera (or rear camera) stored in the storage medium 16. In addition, since the cutting start position has already been detected in step 210 of FIG. 11, at the stage of step 119, the vehicle 1 has already entered the cutting start stage. Therefore, the photographed image read from the storage medium 16 as the optimum viewpoint image is a photographed image at the time when the vehicle is moving forward as a stage before parallel parking.

  In this way, the control circuit 17 obtains the optimum viewpoint image by extracting from among a plurality of images that have been repeatedly photographed by the outside-camera shooting camera 10 when the vehicle 1 was moving forward just before being parked in parallel. To do.

  In this way, by taking advantage of the possibility that the outside-camera camera 10 may pass through the viewpoint position when the vehicle moves forward as the preceding stage of parallel parking, the viewpoint 52 is captured in advance by photographing the midpoint 52 during the passage. An image obtained by photographing the attention position midpoint 52 from the position can be easily realized.

(Third embodiment)
Next, a third embodiment of the present invention will be described. This embodiment is different from the second embodiment in the processing contents of step 110 in FIG.

  Specifically, in the process of step 110, the control circuit 17 bypasses steps 112 and 114 in FIG. 4 and executes step 116, and following step 116, bypasses step 118 and executes step 119. To do. Thus, in this embodiment, it is not necessary to detect the contact caution corner 2d of the forward vehicle 2.

FIG. 15 shows a flowchart of the optimal viewpoint position calculation in step 116 in the present embodiment. In the execution of the processing of this flowchart, the control circuit 17 first executes the same processing as in Steps 210 and 220 in FIG. 11 in Steps 310 and 320, respectively, so that the vehicle 1 start position and the left front end 1a of the host vehicle Next, in step 330, as shown in FIG. 16, a predetermined angle φ is formed with respect to the traveling direction 61 of the vehicle 1 immediately before the start of cutting, and the horizontal trajectory is in contact with the expected trajectory 50. Line 62 is calculated. The angle φ may be a predetermined constant value (for example, 45 °) or may be changed according to a setting operation using the operation unit 13 by a driver.

  However, the optimum viewpoint position is such that the distance between the front vehicle right rear end portion 2a and the host vehicle left front end portion 1a is easy to see, and the vehicle 1 and the front vehicle 2 determine the front vehicle right rear end portion 2a and the host vehicle left front end portion 1a. It is a position that is not blocked. Therefore, the angle φ needs to be larger than 0 ° and smaller than 90 °. Therefore, the control circuit 17 may accept only the setting by the driver of the angle within this range, and ignore the setting exceeding this range.

  Subsequently, in step 250, a contact point 56 (corresponding to an example of a caution position) 56 between the tangent line 62 and the predicted locus 50 is specified, and a right side portion of the specified contact point 56 is specified as an optimal viewpoint position, and then the optimal viewpoint point is determined. The position specifying process (step 116) is terminated.

  As described above, the control circuit 17 determines the viewpoint based on the position of the movement trajectory 50 of the left front end 1a of the host vehicle 1 predicted for the turning stage of the vehicle 1 and the traveling direction of the vehicle 1 immediately before the start of turning. Determine as position. In this way, it is possible to specify the viewpoint position 62 that matches the behavior of the vehicle 1 during parallel parking.

  More specifically, of the line 62 that touches the moving trajectory 50 at the turn-back stage, which can be predicted at the start position of cutting, and forms a predetermined angle φ with respect to the traveling direction of the vehicle 1 immediately before the start of cutting, The right side from the point of contact with the expected locus 50 is determined as the viewpoint position.

  Furthermore, since the control circuit 17 can determine the viewpoint position regardless of the position of the vehicle 2 ahead, the process for determining the viewpoint position is simplified.

  In addition, the control circuit 17 obtains the optimum viewpoint image by extracting from among a plurality of images that have been repeatedly photographed by the outside-camera shooting camera 10 when the vehicle 1 is moving forward just before being parked in parallel.

  In this way, by taking advantage of the possibility that the outside-camera camera 10 may pass through the viewpoint position when the vehicle moves forward as the preceding stage of parallel parking, the viewpoint 52 is captured in advance by photographing the midpoint 52 during the passage. An image obtained by photographing the attention position midpoint 52 from the position can be easily realized.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, the scope of the present invention is not limited only to the said embodiment, The various form which can implement | achieve the function of each invention specific matter of this invention is included. It is.

  For example, in the above embodiment, each function realized by the program executed by the control circuit 17 is realized using hardware having those functions (for example, an FPGA capable of programming a circuit configuration). You may come to do.

  The parallel parking support system 99 may have a car navigation function. In this case, the storage medium 16 records map-data, and the control circuit 17 determines a destination based on an input operation using the driver's operation unit 13, and optimizes the current position to the destination. A simple guidance route is calculated based on the map data, and in order to prompt the vehicle to move along the guidance route, an intersection enlarged view is displayed, a right / left turn instruction voice is output, and the like.

It is a figure which shows an example of the scene of parallel parking to which embodiment of this invention is applied. It is a block diagram which shows the structure of the parallel parking assistance system 99. FIG. It is a flowchart of the program 100 for parallel parking assistance processing. 4 is a flowchart showing details of step 110 of the program 100. 3 is a schematic diagram illustrating an example of an optimal viewpoint position 20. FIG. 3 is a diagram illustrating an example of an optimal viewpoint image 30. FIG. 4 is a flowchart showing details of step 120 of the program 100. 4 is a flowchart showing details of step 130 of the program 100. It is a flowchart which shows the detail of step 140 of the program 100. FIG. It is a figure which shows an example of the synthesized image 31 which superimposed the own vehicle image 40 on the optimal viewpoint image. It is a flowchart which shows the detail of step 116 of FIG. 4 in 2nd Embodiment. It is a figure which shows the calculation method of right locus data. It is a figure which shows the prediction locus | trajectory 50 of the turning-back stage of the own vehicle left front end part 1a of the vehicle 1. FIG. It is a figure which shows the method of specifying the optimal viewpoint position 55 in 2nd Embodiment. It is a flowchart which shows the detail of step 116 of FIG. 4 in 3rd Embodiment. It is a figure which shows the method of specifying the optimal viewpoint position 55 in 3rd Embodiment. It is a reference figure which shows the state of imaging | photography with the camera 83 for the bird's-eye view image 92 display.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 1a Own vehicle left front end part 2 Front vehicle 2a Forward vehicle right rear end part 2d Contact attention corner 4 Shooting direction 10 Outside camera 14 Distance sensor 15 Steering sensor 16 Storage medium 20, 55, 62 Optimum viewpoint position 31 Composite image 40 Self-vehicle image 50 Expected trajectory 52 Middle point 56 Contact 99 Parallel parking support system

Claims (6)

The vehicle (1) equipped with the outside camera (10) is mounted on the vehicle (1) and supports the parallel parking of the vehicle (1) from the first side of the obstacle (2) to the rear of the obstacle (2). A parallel parking support device for
The front end (1a) on the second side opposite to the first side of the vehicle (1) and the first of the obstacle (2) at the turning-back stage that will come later in the parallel parking The attention position (2d, 53, 56) between the rear end (2a) on the side is specified, and the viewpoint position (20, 55) for photographing the specified attention position (2d, 53, 56) in advance 62) viewpoint position specifying means (114, 116) for specifying,
The attention position (2d, 53, 56) photographed by the outside-camera shooting camera (10) at the viewpoint position (20, 55, 62) identified by the viewpoint position identifying means and the surrounding captured images (30). A captured image acquisition means (119) for acquiring;
In the switching step, the vehicle image (40) reflecting the current posture and position of the vehicle (1) is superimposed on the captured image (30), and a composite image (31) as a result of the superimposition is Display control means (140) for displaying on the image display device (12) in the vehicle (1),
The in-vehicle parallel parking assist device, wherein the viewpoint position (20, 55, 62) is located on the first side and in front of the attention position (2d, 53, 56).   The in-vehicle parallel parking according to claim 1, wherein the viewpoint position specifying means (114, 116) specifies the viewpoint position (20) as a position unrelated to the position of the vehicle (1). Support device.   The viewpoint position specifying means (114, 116) is configured to determine the viewpoint position (55, 62) based on the position of the movement locus (50) of the front end portion (1a) expected for the turning stage of the vehicle (1). ) Is determined. The in-vehicle parallel parking assist device according to claim 1.   The viewpoint position specifying means (114, 116) determines the viewpoint position (55) based on the position of the movement locus (50) and the position of the rear end (2a) of the obstacle (2). The in-vehicle parallel parking support device according to claim 3.   The photographed image acquisition means extracts from a plurality of images repeatedly photographed by the outside-camera camera (10) when the vehicle (1) was moving forward just before the parallel parking. The in-vehicle parallel parking assist device according to any one of claims 1, 3, and 4, wherein the captured image (30) is acquired. The vehicle (1) equipped with the outside camera (10) is mounted on the vehicle (1) and supports the parallel parking of the vehicle (1) from the first side of the obstacle (2) to the rear of the obstacle (2). A program used for a parallel parking assist device for a vehicle,
The front end (1a) on the second side opposite to the first side of the vehicle (1) and the first of the obstacle (2) at the turning-back stage that will come later in the parallel parking The attention position (2d, 53, 56) between the rear end (2a) on the side is specified, and the viewpoint position (20, 55) for photographing the specified attention position (2d, 53, 56) in advance 62) viewpoint position specifying means (114, 116) for specifying
The attention position (2d, 53, 56) photographed by the outside-camera photographing camera (10) at the viewpoint position (20, 55, 62) identified by the viewpoint position identifying means and the surrounding captured images (30). Captured image acquisition means (119) to acquire, and in the switching step, the captured vehicle image (40) reflecting the current posture and position of the vehicle (1) is superimposed on the captured image (30), and the superimposed The computer is caused to function as display control means (140) for displaying the resultant composite image (31) on the image display device (12) in the vehicle (1),
The viewpoint position (20, 55, 62) is located on the first side and in front of the attention position (2d, 53, 56).

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