JP6287704B2 - Driving assistance device - Google Patents

Description

  The present invention relates to a driving support device that captures a situation around a vehicle and displays a bird's-eye image obtained by performing bird's-eye conversion on the captured image.

  2. Description of the Related Art Conventionally, a technique is known in which a situation around a vehicle is picked up using a camera, and an image indicating the position of the vehicle is superimposed on a bird's-eye image obtained by bird's-eye conversion of the image around the picked-up vehicle. However, when performing bird's-eye conversion of an image, an obstacle originally standing on the ground will be displayed as if it has collapsed due to distortion that occurs during conversion, and the distance between the vehicle and the obstacle can be understood by the user. The problem becomes difficult.

  Therefore, as means for solving this problem, for example, Patent Document 1 discloses a distance from the own vehicle to an obstacle calculated from a propagation time until an ultrasonic reflected wave transmitted from a distance measuring sensor is received. In addition, a technique is disclosed in which the position of the outer edge of the obstacle is detected and a marker indicating the position of the outer edge of the obstacle is superimposed and displayed on the bird's-eye view image.

Japanese Patent No. 4039321

  The vehicle has a shape in which a specific part such as a bumper or a side mirror protrudes. In addition, some obstacles have a shape that greatly varies in the horizontal direction depending on the height position, such as an upper portion protruding in the horizontal direction and a lower portion protruding in the horizontal direction. Therefore, the distance in which the vehicle and the obstacle can actually approach differs depending on the height position of the part protruding in the horizontal direction between the vehicle and the obstacle and the protruding amount.

  On the other hand, the technique disclosed in Patent Document 1 merely detects the position of the outer edge of the obstacle, and does not consider the shape spreading in the horizontal direction for each height position of the vehicle and the obstacle. The distance that can be actually secured between the vehicle and the obstacle cannot be accurately specified. Therefore, a marker indicating the position of the outer edge of the obstacle (hereinafter simply referred to as a marker) is displayed at a position where it is difficult to ensure the distance even though the distance to the vehicle can be actually secured. There is a possibility that the marker may be displayed at a position where the distance to the vehicle cannot be secured in practice.

  The present invention has been made in view of the above-described conventional problems, and its purpose is to more accurately identify the distance that can be actually secured between the own vehicle and the obstacle and is difficult to understand on the bird's-eye view image. An object of the present invention is to provide a driving support device that makes it easier to understand a more accurate distance between the vehicle and the obstacle.

  The driving support device of the present invention is used in a vehicle, and an image processing unit (13) that performs bird's-eye conversion on an image captured by an imaging device (5) that captures the periphery of the host vehicle, and a bird's-eye view that has been converted to bird's-eye by the image processing unit. A driving support device including a display processing unit (19) that superimposes a vehicle image indicating a vehicle position on an image and displays the vehicle image on a display device (7), and spreads in a horizontal direction according to a height position of the vehicle. A host vehicle shape storage unit (17) that stores host vehicle shape information, which is information that can at least identify the shape, and a plurality of obstacles arranged in the height direction and the horizontal direction of obstacles around the host vehicle from a predetermined position of the host vehicle. The measurement point distance acquisition unit (15) that acquires the measurement point distance detected by the distance measuring sensor (6) that detects the measurement point distance to each measurement point, and the measurement point distance acquired by the measurement point distance acquisition unit, Based on the direction of the measurement point with respect to the predetermined position, An obstacle shape specifying unit (16) for specifying a shape spreading in the horizontal direction for each height position, and a horizontal for each vehicle height position that can be specified from the vehicle shape information stored in the vehicle shape storage unit The distance between the parts at the same height position of the vehicle and the obstacle based on the shape spreading in the direction and the shape spreading in the horizontal direction according to the height position of the obstacle specified by the obstacle shape specifying part A shortest inter-site distance specifying unit (18) that specifies the shortest inter-site distance that shortens the distance between the shortest parts in the direction in which the obstacle is located with respect to the vehicle image in the bird's-eye view image. It is characterized in that a marker indicating the position of the obstacle is superimposed and displayed at a position corresponding to the shortest distance between the parts specified by the distance specifying unit.

  According to this, the shape spreading in the horizontal direction according to the height position of the own vehicle that can be specified from the own vehicle shape information stored in the own vehicle shape storage unit, and the height of the obstacle specified by the obstacle shape specifying unit Based on the shape that spreads in the horizontal direction for each position, the shortest distance between the parts where the distance between the parts at the same height position of the vehicle and the obstacle is the shortest is specified. Here, the shape spreading in the horizontal direction according to the height position of the obstacle corresponds to the measurement point distance to the measurement points arranged in the height direction and the horizontal direction in the obstacle around the own vehicle and the predetermined position of the own vehicle. Since it is specified based on the direction of the measurement point, the shape that spreads horizontally according to the height position of the vehicle and the shape that spreads horizontally according to the height position of the obstacle It is possible to make a comparison along the positional relationship, and it is possible to more accurately specify the distance that can be actually secured between the vehicle and the obstacle.

  In addition, since the display processing unit causes the marker indicating the position of the obstacle to be superimposed and displayed at the position corresponding to the distance between the shortest parts in the direction in which the obstacle is located with respect to the own vehicle image in the bird's-eye view image, It becomes possible to make the user recognize the distance that can be actually secured between the own vehicle and the obstacle more accurately. Therefore, it becomes easier to understand the more accurate distance between the vehicle and the obstacle that is difficult to understand on the bird's-eye view image.

1 is a block diagram showing a schematic configuration of a driving support system 100. FIG. It is a figure for demonstrating the shortest part distance. It is a flowchart which shows an example of the flow of the bird's-eye view image display related process in driving assistance ECU1. FIG. 5 is a diagram for explaining a marker display position in the first embodiment. 6 is a diagram illustrating a display example of a marker in the first embodiment. FIG. It is a figure for demonstrating the display position of the marker in a prior art. It is a figure which shows the example of a display of the marker by a prior art. FIG. 5 is a diagram for explaining a marker display position in the first embodiment. 6 is a diagram illustrating a display example of a marker in the first embodiment. FIG. 6 is a diagram illustrating a display example of a marker in the first embodiment. FIG. 6 is a diagram illustrating a display example of a marker in the first embodiment. FIG. It is a figure which shows the example of a display of the marker in the modification 1.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
<Schematic configuration of driving support system 100>
FIG. 1 is a diagram illustrating an example of a schematic configuration of a driving support system 100 to which the present invention is applied. The driving support system 100 is mounted on a vehicle, and includes a driving support ECU 1, a shift position sensor 2, a rudder angle sensor 3, a vehicle speed sensor 4, a camera 5, a laser radar unit 6, and a display 7 as shown in FIG. Contains. Hereinafter, a vehicle equipped with the driving support system 100 is referred to as a host vehicle.

  The shift position sensor 2 detects the shift position of the own vehicle. The steering angle sensor 3 detects the steering angle of the host vehicle. The vehicle speed sensor detects the speed of the host vehicle.

  The camera 5 is installed in the own vehicle and sequentially captures the periphery of the own vehicle. This camera 5 corresponds to the imaging device of the claims. In the present embodiment, the camera 5 includes a front camera that captures a predetermined angle range in front of the host vehicle, a rear camera that captures a predetermined range of angles behind the host vehicle, and a left-side camera that captures a predetermined angle range on the left side of the host vehicle. The case where a right side camera that captures a predetermined angle range on the right side of the vehicle is used as an example will be described. The camera 5 uses the front camera, the rear camera, the left side camera, and the right side camera as an imaging range around the entire vehicle.

  The laser radar unit 6 includes a laser radar 6a and a control IC 6b. The laser radar unit 6 corresponds to a distance measuring sensor. The laser radar 6a includes a light emitting unit, a light receiving unit, and the like. The light emitting unit includes a laser diode that emits pulsed laser light via a scanner and a light emitting lens. The laser diode is connected to the control IC 6b via a laser diode drive circuit, and emits laser light by a drive signal from the control IC 6b. The scanner is provided with a polygon mirror as a reflector so that it can be driven to rotate by a motor. When the drive signal from the control IC 6b is input to the motor drive circuit, the motor drive circuit drives the motor to rotate the polygon mirror. The rotational position of the motor is detected by a motor rotational position sensor and output to the control IC 6b.

  The polygon mirror has six reflecting surfaces formed on the side surfaces around the rotation axis. In addition, each reflecting surface in the polygon mirror is formed to have a different surface tilt angle. For this reason, the laser light is intermittently emitted from the laser diode while rotating the polygon mirror at a predetermined speed, so that the laser light is swept in a predetermined angle range in the horizontal direction and the height direction (that is, scanning). It becomes possible to do.

  The light receiving unit includes a light receiving lens that receives laser light (that is, reflected light) reflected by the object, and this light receiving lens gives the received reflected light to the light receiving element. The light receiving element outputs a voltage corresponding to the intensity of the reflected light. The output voltage of the light receiving element is amplified by an amplifier and then output to a comparator. The comparator compares the output voltage of the amplifier with the reference voltage, and outputs a predetermined light reception signal to the time measuring circuit when the output voltage becomes larger than the reference voltage.

  A drive signal output from the control IC 6b to the laser diode drive circuit is also input to the time measurement circuit. This time measuring circuit encodes the time from when the drive signal is output until the light receiving signal is generated, that is, the time difference between the time when the laser light is emitted and the time when the reflected light is received into a binary digital signal. The binary digital signal is input to the control IC 6b as measurement time data.

  In the present embodiment, for example, the light emitting unit irradiates the laser beam with a beam step angle of 0.08 deg in an angle range (hereinafter referred to as an irradiation area) where the laser beam is actually irradiated. In this case, one cycle in which all of the horizontal direction and the height direction in the irradiation area are irradiated with a beam step angle of 0.08 deg is defined as one scan.

  When the light emitting unit actually irradiates the laser beam, a drive signal is output from the control IC 6b to the light emitting unit so that the laser beam is scanned two-dimensionally within the irradiation area described above. When the reflected light is received by such a two-dimensional scan, the irradiation angle θ of the laser beam from which the reflected light is obtained is uniquely determined.

  Each time the time difference between the laser light emission time and the reflected light reception time is input from the time measurement circuit, the control IC 6b sequentially calculates the distance d from the laser radar 6a to the reflection point on the object based on the time difference. To do. Thereby, when an obstacle exists around the own vehicle, the distance from the installation position of the laser radar 6a of the own vehicle to each of the reflection points arranged in the height direction and the horizontal direction on the obstacle is detected. It will be. Therefore, the reflection point on the object corresponds to the measurement point in the claims, and the distance d corresponds to the measurement point distance in the claims.

  Then, the control IC 6b sends polar coordinate system data of the distance d and the irradiation angle θ of the laser beam from which the reflected light is obtained to the driving support ECU 1 as a measurement result. As an example, the control IC 6b sends a measurement result obtained by performing one scan in the irradiation area to the driving support ECU 1 as a measurement result for one scan.

  In this embodiment, the laser radar unit 6 is installed in the front part of the own vehicle, the left part of the own vehicle, the rear part of the own vehicle, and the right side part of the own vehicle. The case where an obstacle within a predetermined angular range behind the host vehicle and a predetermined angular range on the right side of the host vehicle is detected will be described as an example.

  The display 7 displays an image output from the driving support ECU 1. This display 7 corresponds to the display device of the claims. For example, the display 7 is capable of full color display and can be configured using a liquid crystal display or the like.

  The driving assistance ECU 1 is mainly configured as a microcomputer, and each includes a known CPU, a memory such as a ROM and a RAM, an I / O, and a bus connecting them. The driving assistance ECU 1 executes various processes based on various information input from the shift position sensor 2, the steering angle sensor 3, the vehicle speed sensor 4, the camera 5, and the laser radar unit 6. This driving support ECU 1 corresponds to the driving support device of the claims.

  Note that some or all of the functions executed by the driving support ECU 1 may be configured in hardware by one or a plurality of ICs. Further, the driving support ECU 1 is not necessarily limited to a configuration including one ECU, and may be configured to include a plurality of ECUs.

<Detailed Configuration of Driving Assist ECU 1>
As shown in FIG. 1, the driving assistance ECU 1 includes a vehicle movement information acquisition unit 11, an image storage unit 12, an image processing unit 13, a past image interpolation processing unit 14, a measurement result acquisition unit 15, an obstacle shape specifying unit 16, A vehicle shape storage unit 17, a shortest part distance specifying unit 18, and a display processing unit 19 are provided.

  The vehicle movement information acquisition unit 11 includes the own vehicle shift position detected by the shift position sensor 2, the own vehicle steering angle detected by the steering angle sensor 3, and the own vehicle speed detected by the vehicle speed sensor 4. Vehicle movement information that can identify the state of movement of the vehicle is acquired.

  In the present embodiment, as an example, the camera 5 and the laser radar unit 6 operate when the vehicle speed of the vehicle in the vehicle movement information acquired by the vehicle movement information acquisition unit 11 is equal to or lower than a predetermined value. The camera 5 and the laser radar unit 6 are configured not to operate when the vehicle speed is not less than the predetermined value. The predetermined value mentioned here is a vehicle speed at which the host vehicle is decelerated during parking, and is a value that can be arbitrarily set.

  The image storage unit 12 stores a captured image around the host vehicle that is input from the camera 5 and captured by the camera 5. In the example of the present embodiment, the latest captured image captured by the front camera, the rear camera, the left side camera, and the right side camera is stored in the image storage unit 12. The image storage unit 12 not only stores the latest captured images of the front camera, the rear camera, the left side camera, and the right side camera, but also stores, for example, past number of bird's-eye images obtained by the image processing unit 13 described later. Remember the batch. The past several bird's-eye images stored in the image storage unit 12 are hereinafter referred to as history images.

  The image processing unit 13 converts each captured image of the front camera, the rear camera, the left camera, and the right camera into a bird's-eye image in which the upper surface of the alley is looked down in a vertical direction by using a known coordinate conversion formula. A bird's-eye view image is obtained by performing bird's-eye conversion. Note that the image processing unit 13 may perform a bird's eye conversion after performing necessary image processing such as lens distortion correction on the captured image.

  Then, the image processing unit 13 rotates and parallels the bird's-eye view image obtained by performing bird's-eye conversion on the captured images of the front camera, the rear camera, the left side camera, and the right side camera by using a known conversion formula. It is moved, arranged on one coordinate plane (that is, a bird's-eye view image is arranged so that it can be regarded as one image), and a combined image is generated by combining the bird's-eye images.

  Further, when generating the composite image, the image processing unit 13 reads an image of the own vehicle (for example, a CG image representing the own vehicle) stored in the nonvolatile memory of the driving support ECU 1 and reads the own image. It is arranged at the location corresponding to the car position and synthesized with each bird's-eye view image. Then, the image processing unit 13 sends drawing data of the combined image that has been combined to the display processing unit 19.

  What is necessary is just to specify the own vehicle position in a synthesized image as follows. First, if the installation position and imaging direction of the camera 5 with respect to the own vehicle are determined, the correspondence between the position in the captured image and the installation position of the camera 5 can be specified. Therefore, in this embodiment, the position of the camera 5 with respect to the position in the composite image is specified from the installation position and the imaging direction of the camera 5 with respect to the own vehicle. And since the position of the own vehicle with respect to the installation position of the camera 5 can be specified from the installation position of the camera 5 with respect to the own vehicle, the position of the own vehicle in the composite image is determined from the position of the camera 5 with respect to the position in the specified composite image. Identify.

  The past image interpolation processing unit 14 reads the above-described history image from the image storage unit 12 when the front camera, the rear camera, the left side camera, the right side camera, or the like cannot capture the surroundings of the own vehicle. The image processing unit 13 can synthesize bird's-eye images around the entire vehicle.

  The past image interpolation processing unit 14 determines the arrangement position of the history image with respect to the own vehicle position according to the movement state of the own vehicle that can be specified from the vehicle movement information acquired by the vehicle movement information acquisition unit 11, and the determined arrangement position The history image is sent to the image processing unit 13. As an example, the history image layout position relative to the host vehicle position is determined by estimating the history image layout position relative to the current host vehicle position based on the travel locus of the host vehicle determined from the steering angle and vehicle speed of the host vehicle. To do.

  The image processing unit 13 generates a composite image by arranging the history images sent from the past image interpolation processing unit 14 and synthesizing the bird's-eye view image according to the arrangement position determined by the past image interpolation processing unit 14.

  The measurement result acquisition unit 15 acquires a measurement result for one scan by the laser radar unit 6. The measurement result acquisition unit 15 corresponds to a measurement point distance acquisition unit in the claims. As described above, the measurement result of the laser radar unit 6 is polar coordinate data of the distance d from the laser radar 6a to the reflection point on the obstacle and the irradiation angle θ of the laser beam from which the reflected light is obtained. . The installation position of the laser radar 6a corresponds to a predetermined position of the own vehicle.

The obstacle shape specifying unit 16 is based on the measurement result for one scan by the laser radar unit 6 acquired by the measurement result acquisition unit 15, that is, based on the polar coordinate system data of the distance d and the irradiation angle θ. The three-dimensional shape (hereinafter referred to as an obstacle shape) is specified. This irradiation angle θ corresponds to the direction of the measurement point in the claims.
As an example, the obstacle shape is specified as follows.

  First, the obstacle shape specifying unit 16 determines polar coordinates (d, θ) based on the relative position of the laser radar 6a with respect to the center position of the own vehicle and having the installation position of the laser radar 6a on the own vehicle as an origin. The coordinates are converted into coordinates in a three-dimensional orthogonal coordinate system with the center position of the car as the origin (0, 0, 0). What is necessary is just to use the structure memorize | stored in the non-volatile memory of driving assistance ECU1 as the relative position of the laser radar 6a with respect to the center position of the own vehicle. The obstacle shape specifying unit 16 specifies a set of coordinates obtained by converting polar coordinates (d, θ) for one scan in the laser radar unit 6 into coordinates of a three-dimensional orthogonal coordinate system as an obstacle shape.

  Since scanning with the laser radar unit 6 is performed at a beam step angle of 0.08 deg in the height direction, in practice, a shape that spreads in the horizontal direction for each height position of the obstacle is specified as the obstacle shape. It will be.

  The host vehicle shape storage unit 17 stores a host vehicle shape indicating a relatively detailed contour of the host vehicle including protruding portions such as side mirrors and bumpers. The vehicle shape is represented by a set of coordinate points indicating the contour of the vehicle in a three-dimensional orthogonal coordinate system with the vehicle center as the origin, for example. Information on a set of coordinate points indicating the contour of the vehicle corresponds to the vehicle shape information in the claims.

  The shortest part-to-part distance specifying unit 18 determines whether the vehicle and the obstacle are based on the vehicle shape stored in the vehicle shape storage unit 17 and the obstacle shape specified by the obstacle shape specifying unit 16. Among the parts at the same height position, the distance between the parts where the distance between them is the shortest (hereinafter, the shortest part distance) is specified. In other words, the shape spreading in the horizontal direction according to the height position of the own vehicle stored in the vehicle shape storage unit 17 and the horizontal direction depending on the height position of the obstacle specified by the obstacle shape specifying unit 16. The distance between the shortest parts is specified based on the shape.

  As an example, in a three-dimensional orthogonal coordinate system in which the center position of the vehicle is the origin (0, 0, 0), each coordinate point as the vehicle shape and each coordinate point as the obstacle shape are classified by height. And the shortest distance among the calculated distances may be specified as the shortest inter-site distance.

  Here, the distance between the shortest parts will be described with reference to FIG. In FIG. 2, HV is the own vehicle, Ob is the obstacle behind the own vehicle, A is the distance between the shortest parts, and B is the distance between the parts that protrude most from the own car and the obstacle. Yes. Obstacle Ob has a shape in which the upper part protrudes toward the own vehicle compared to the lower part. The distance A between the shortest parts is larger than the distance B when the heights of the parts that protrude the most from the vehicle and the obstacle are shifted from each other. This is the distance between parts that may actually come into contact with an object.

  The display processing unit 19 displays the composite image generated by the image processing unit 13 on the display 7. If necessary, a marker is superimposed on the position corresponding to the distance between the shortest parts specified by the shortest part distance specifying unit 18 of the composite image and displayed on the display 7. This marker indicates a boundary where the vehicle can approach the obstacle. Details of processing for displaying the marker superimposed on the composite image in the display processing unit 19 will be described later.

  In addition, based on the vehicle movement information acquired by the vehicle movement information acquisition unit 11, the display processing unit 19 may superimpose a guide such as an expected trajectory line of the own vehicle on the composite image and display it on the display 7. Good. For example, if the shift position is the reverse position, an expected trajectory line is displayed behind the host vehicle, or if the shift position is the forward position, the expected trajectory line is displayed in front of the host vehicle. Good. The predicted trajectory line may be predicted from the steering angle of the host vehicle and the vehicle speed.

<Bird view image display related processing>
Here, the bird's-eye image display related processing in the driving support ECU 1 will be described with reference to the flowchart of FIG. The bird's-eye image display related process is a process related to a process of displaying on the display 7 a bird's-eye view image obtained by bird's-eye conversion of a captured image around the host vehicle. As an example, the flowchart of FIG. 3 is started when the ignition power of the host vehicle is turned on.

  First, in step S1, the vehicle movement information acquisition unit 11 acquires vehicle movement information. Specifically, the vehicle speed detected by the vehicle speed sensor 4 is acquired. In step S2, if the vehicle speed acquired in S1 is equal to or lower than the predetermined value (YES in S2), the process proceeds to step S3. On the other hand, when the vehicle speed of the own vehicle is not less than the predetermined value (NO in S2), the process proceeds to step S9. In step S <b> 3, the image processing unit 13 generates a composite image obtained by combining a bird's-eye image obtained by bird's-eye conversion of a captured image around the host vehicle captured by the camera 5 and the host vehicle image.

  In step S4, the display processing unit 19 determines whether there is an obstacle within a predetermined distance from the own vehicle based on the measurement result for one scan by the laser radar unit 6 acquired by the measurement result acquisition unit 15. judge. The predetermined distance here is a distance that can be arbitrarily set, and may be about several meters, for example.

  As an example, if there is a distance d or less from the laser radar 6a for one scan to the reflection point on the obstacle, it is determined that there is an obstacle within the predetermined distance from the own vehicle. If there is no object below the predetermined distance, it is determined that there is no obstacle within the predetermined distance from the own vehicle. When it is determined that there is an obstacle within a predetermined distance from the own vehicle (YES in S4), the process proceeds to step S5. On the other hand, when it is determined that there is no obstacle within a predetermined distance from the own vehicle (NO in S4), the process proceeds to step S8.

  In step S <b> 5, the obstacle shape identification unit 16 identifies the obstacle shape based on the measurement result for one scan by the laser radar unit 6 acquired by the measurement result acquisition unit 15. In step S6, the shortest part distance specifying unit 18 specifies the shortest part distance described above based on the obstacle shape specified in S5 and the vehicle shape stored in the vehicle shape storage unit 17. .

  In step S7, the display processing unit 19 causes the display 7 to display a marker superimposed on the position corresponding to the shortest inter-site distance specified in S6 of the composite image generated in S3. As an example, in the composite image, the marker is located at a position away from the portion that protrudes most in the direction in which the obstacle is located (hereinafter referred to as a protruding portion) by the shortest distance between the portions in the direction in which the obstacle is located. Are superimposed and displayed on the display 7. For example, the marker may be indicated by a straight line extending in a direction along the surface of the own vehicle facing the obstacle. For example, the surface of the host vehicle may be any of the four types of front, left, rear, and right sides.

  What is necessary is just to identify a protrusion site | part based on the own vehicle shape memorize | stored in the own vehicle shape memory | storage part 17, and the obstruction shape specified by the obstruction shape specific | specification part 16. FIG. For example, assuming that the height position is the same for each coordinate point as the vehicle shape and each coordinate point as the obstacle shape, the distance between the coordinates of the vehicle shape and the obstacle shape is the shortest. The coordinates which become are specified. And the coordinate of the own vehicle side among the identified coordinates should just be specified as a protrusion part. Moreover, what is necessary is just to let the direction which goes to the coordinate of the obstruction side of the specified coordinates from the coordinate of the own vehicle side among the specified coordinates to be the direction in which the obstacle is located.

  Here, a marker display example will be described with reference to FIGS. 4 and 5. First, the display position of the marker will be described with reference to FIG. In FIG. 4, HV represents the own vehicle, Ob represents an obstacle behind the own vehicle, Pr represents the protruding portion, A represents the shortest distance between the portions, and MP represents the marker position. Obstacle Ob has a shape in which the upper part protrudes toward the own vehicle compared to the lower part. The position of the marker is a position on the composite image corresponding to the position MP that is separated from the protruding part Pr by the shortest part distance A in the direction in which the obstacle Ob is located.

  Subsequently, a display example of the marker superimposed on the composite image will be described with reference to FIG. Pi in FIG. 5 is a composite image, HVP is an image of the vehicle in the composite image, ObP is an image of an obstacle behind the vehicle in the composite image, PrP is an image of a protruding part, A is a distance between the shortest parts, and Ma is a marker. Is shown. Since the marker Ma is displayed at a position away from the protruding part Pr by the distance A between the shortest parts in the direction in which the obstacle Ob is located, the marker Ma is displayed at a position corresponding to the boundary where the own vehicle can actually approach.

  In step S8, the display processing unit 19 causes the display 7 to display the composite image generated in S3. In S8, unlike S7, the marker is not superimposed on the composite image.

  In step S9, when it is the end timing of the bird's-eye image display related processing (YES in S9), the bird's-eye image display related processing is ended. If it is not the end timing of the bird's-eye image display related process (NO in S9), the process returns to S1 and the process is repeated. The end timing of the bird's-eye image display related processing includes when the ignition power of the own vehicle is turned off.

<Summary of Embodiment 1>
According to the configuration of the first embodiment, since the distance between the shortest parts where the distance between the parts at the same height position of the own vehicle and the obstacle is the shortest is specified, the distance between the own vehicle and the obstacle is actually It becomes possible to specify the distance that can be secured more accurately. Further, according to the configuration of the first embodiment, in the combined image obtained by combining the bird's-eye view image and the own vehicle image, the direction in which the obstacle is located from the portion of the own vehicle that protrudes most in the direction in which the obstacle is located. A marker is superimposed and displayed at a position separated by a distance between the shortest parts. Therefore, it is possible to make the user recognize the distance that can be actually secured between the vehicle and the obstacle more accurately. As a result, it becomes easier to understand the more accurate distance between the vehicle and the obstacle that is difficult to understand on the bird's-eye view image.

  Here, the effect in this invention is demonstrated concretely using FIGS. 4-7. First, the prior art disclosed in Patent Document 1 will be described with reference to FIGS. 6 and 7.

  In the prior art, the marker Ma is displayed at a position on the composite image corresponding to the position MP corresponding to the outer edge of the obstacle Ob that protrudes most toward the vehicle HV side (see FIGS. 6 and 7). However, when the own vehicle can approach the obstacle Ob side further than the outer edge of the obstacle Ob, the position indicated by the marker Ma can be actually secured between the own vehicle and the obstacle as shown in FIG. The display indicates that only a distance shorter than the distance (that is, the shortest distance between the parts) can be secured.

  On the other hand, according to the configuration of the first embodiment, as shown in FIGS. 4 and 5, it is possible to display a marker that more accurately indicates the distance that can be actually secured between the vehicle and the obstacle. The distance that can be actually secured between the vehicle and the obstacle can be recognized more accurately by the user.

  In FIGS. 4 and 5, an example in which an obstacle having a shape in which the upper part protrudes toward the own vehicle compared to the lower part has been described. For example, as shown in FIG. The present invention can also be applied to an obstacle having a shape in which the lower part protrudes toward the own vehicle as compared with the upper part. Even in the case illustrated in FIG. 8, the position of the marker is a position on the composite image corresponding to the position MP that is separated from the protruding part Pr by the shortest part distance A in the direction in which the obstacle Ob is located. As shown in FIG. 9, the marker Ma is displayed at a position away from the protruding part Pr by the distance A between the shortest parts in the direction in which the obstacle Ob is located. Displayed in position. In this embodiment, as shown in FIG. 9, when the position of the marker Ma overlaps the position of the obstacle on the composite image, the marker Ma is displayed over the obstacle.

  In addition, as shown in FIG.10 and FIG.11, it can apply also when the own vehicle performs parallel parking. 10 and 11 indicate the same objects as those in FIG. Moreover, SiP of FIG. 10, 11 has shown the image of the side mirror of the own vehicle HV.

  For example, in parallel parking, when the part of the own vehicle HV that is the shortest distance that can be actually secured with the obstacle Ob is the side surface of the own vehicle HV, the direction in which the obstacle Ob is located from the side surface of the own vehicle HV A marker Ma is displayed at a position separated by a distance A between the shortest parts (see FIG. 10). On the other hand, when the own vehicle HV moves and the part of the own vehicle HV whose distance that can be actually secured with the obstacle Ob is the shortest side mirror of the own vehicle HV, the obstacle from the side mirror of the own vehicle HV The marker Ma is displayed at a position separated by the distance A between the shortest parts in the direction in which the object Ob is located (see FIG. 11). Thus, even when the host vehicle performs parallel parking, the marker Ma is displayed at a position corresponding to the boundary where the host vehicle can actually approach.

  Further, according to the configuration of the first embodiment, when displaying a composite image of the bird's-eye view image, the processing of S5 and S6 is not always performed, but when it is determined in S4 that there is no obstacle within a predetermined distance from the own vehicle. Will not perform the processing of S5 and S6. Therefore, also when displaying the synthesized image of the bird's-eye view image, the processes of S5 and S6 are performed as necessary, and the processing load on the driving support ECU 1 can be reduced.

(Modification 1)
In Embodiment 1, although the structure which displays a marker in the position which left | separated the shortest part distance in the direction where an obstacle is located from the protrusion part was shown, it does not necessarily restrict to this. For example, it is good also as a structure (henceforth modification 1) which displays a marker in the position which shifted | deviated predetermined distance to the own vehicle position side rather than the position which distanced the shortest part distance from the protrusion part. The predetermined distance mentioned here is a value that can be arbitrarily set, for example, a value that is about the measurement error of the distance in the laser radar unit 6.

  Here, a marker display example in Modification 1 will be described with reference to FIG. In addition, the symbol of FIG. 12 has shown the object similar to the symbol of FIG. Further, X in FIG. 12 indicates a predetermined distance that is shifted to the own vehicle HV position side from the position MP that is separated from the protruding part Pr by the distance A between the shortest parts. As shown in FIG. 12, in the first modification, the position at which the marker Ma is displayed is on the HV position side of the vehicle HV from the position MP that is away from the protruding part Pr by the distance A between the shortest parts in the direction in which the obstacle Ob is located. The position is shifted by a predetermined distance X.

(Modification 2)
In the first embodiment, the configuration in which the laser radar 6a is used as a distance measuring sensor for detecting the measurement point distances to the plurality of measurement points arranged in the height direction and the horizontal direction in the obstacle around the own vehicle has been described. It is not necessarily limited to this. For example, a millimeter wave radar or an ultrasonic sensor may be used as the distance measuring sensor, or a camera such as a stereo camera or a monocular camera may be used.

(Modification 3)
In Embodiment 1, although the structure which shows a marker with the straight line extended in the direction along the surface of the own vehicle which faced the obstruction side was shown, it does not necessarily restrict to this. For example, a configuration indicated by a straight line extending in a direction along the outer edge of the obstacle facing the own vehicle may be used, or a configuration indicated by using other shapes such as points and curves.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means disclosed in different embodiments can be appropriately combined. Such embodiments are also included in the technical scope of the present invention.

1 driving assistance ECU (driving assistance device), 5 camera (imaging device), 6 laser radar unit (ranging sensor), 7 display (display device), 13 image processing unit, 15 measurement result obtaining unit (measurement point distance obtaining unit) ), 16 obstacle shape specifying part, 17 own vehicle shape storage part, 18 shortest part distance specifying part, 19 display processing part

Claims (4)

Used in vehicles,
An image processing unit (13) that performs bird's-eye conversion on an image captured by an imaging device (5) that captures the periphery of the vehicle;
A driving support device comprising: a display processing unit (19) that superimposes a host vehicle image indicating a vehicle position on a bird's eye image converted by a bird's eye view in the image processing unit and causes the display device (7) to display the superimposed image.
A host vehicle shape storage unit (17) that stores host vehicle shape information that is information that can at least identify a shape that spreads in the horizontal direction according to the height position of the host vehicle;
The measurement point distance detected by the distance measuring sensor (6) for detecting the measurement point distances from a predetermined position of the own vehicle to a plurality of measurement points arranged in the height direction and the horizontal direction in obstacles around the own vehicle. A measurement point distance acquisition unit (15) to acquire;
Obstacle shape specification that specifies a shape that spreads in the horizontal direction according to the height position of the obstacle based on the measurement point distance acquired by the measurement point distance acquisition unit and the direction of the measurement point with respect to the predetermined position Part (16),
The shape spreading in the horizontal direction for each height position of the own vehicle that can be specified from the own vehicle shape information stored in the own vehicle shape storage unit, and the height position of the obstacle specified by the obstacle shape specifying unit The shortest part distance specifying unit (18) for specifying the shortest part distance in which the distance between the parts at the same height position of the own vehicle and the obstacle is the shortest based on the shape extending in the horizontal direction And
The display processing unit superimposes a marker on the bird's-eye view image at a position corresponding to the shortest inter-site distance specified by the shortest inter-site distance specifying unit in a direction in which the obstacle is located with respect to the host vehicle image. A driving support device characterized by being displayed. In claim 1,
In the bird's-eye view image, the display processing unit displays a marker at a position that is the distance between the shortest part in the direction in which the obstacle is located from the part that protrudes most in the direction in which the obstacle is located for the vehicle. By doing so, a marker is superimposed and displayed at a position corresponding to the distance between the shortest parts specified by the shortest part distance specifying unit in the direction in which the obstacle is located with respect to the vehicle image. A driving support device. In claim 1,
In the bird's-eye view image, the display processing unit is located in the own vehicle position from a position farthest in the direction in which the obstacle is located for the own vehicle in a direction in which the obstacle is located by a distance between the shortest parts. By displaying a marker at a position shifted by a predetermined distance on the side, according to the shortest inter-site distance specified by the shortest inter-site distance specifying unit in the direction in which the obstacle is located with respect to the vehicle image A driving assistance apparatus, characterized in that a marker is displayed superimposed on a position. In any one of Claims 1-3,
When the display position of the marker on the bird's-eye image overlaps the obstacle on the bird's-eye image, the display processing unit displays the marker so as to overlap the obstacle. .

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