JP2016018354A - Safety driving support device and safety driving support method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safety driving support device and safety driving support method capable of avoiding the execution of predetermined safety driving support processing regardless of a low possibility that a self vehicle collides with a preceding vehicle.SOLUTION: A safety driving support device includes: an inter-vehicle distance estimation section 13 for estimating an inter-vehicle distance from a preceding vehicle; a wheel recognition section 14 for performing the image recognition of the wheels of the preceding vehicle from a vehicle anterior image captured by an on-vehicle camera 20; and a warning section 15 for executing predetermined warning processing in accordance with the inter-vehicle distance estimated by the inter-vehicle distance estimation section 13 and the image recognition result of the wheels by the wheel recognition section 14. When the wheel recognition section 14 recognizes the four wheels or the side surfaces of the wheels in an image in a case where the inter-vehicle distance estimated by the inter-vehicle distance estimation section 13 is lower than a predetermined threshold, the warning section 15 is prevented from executing the predetermined warning processing. Consequently, when the preceding vehicle is traveling on a curved road of a lane different from that of the self vehicle in front of the self vehicle, the predetermined safety driving support processing is not executed regardless of the inver-vehicle distance from the preceding vehicle.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a safe driving support device and a safe driving support method, and in particular, is suitable for use in a safe driving support device configured to perform predetermined safe driving support processing in accordance with the inter-vehicle distance from a preceding vehicle. is there.

  Conventionally, in an automobile, a technique for estimating the inter-vehicle distance between the own vehicle and a preceding vehicle from an image in front of the vehicle imaged by an in-vehicle camera or detection signals from various sensors (for example, an ultrasonic sensor, an infrared sensor) is used. Has been. By estimating the inter-vehicle distance with the preceding vehicle in this way, for example, when the inter-vehicle distance with the preceding vehicle becomes shorter than a predetermined threshold, the driver is informed that there is a risk of a rear-end collision with the preceding vehicle. It is possible to notify the vehicle and to control the braking device of the vehicle so as to automatically apply the brake.

  In Patent Document 1 below, images of the left and right tail lamps of a preceding vehicle are extracted as feature points from an image ahead of the own vehicle imaged by the imaging means, and based on the distance between the left and right tail lamps, A technique for estimating the inter-vehicle distance is disclosed. In the technique disclosed in Patent Document 1 below, it is determined whether the preceding vehicle is traveling on a curved road based on the distance between the left and right tail lamps of the preceding vehicle, and the preceding vehicle is traveling on the curved road. If it is determined, it is determined that the reliability of the estimated inter-vehicle distance is low, and this value is corrected. Patent Document 1 below describes that a tire may be used as a feature point instead of a tail lamp.

JP 2011-65219 A

  In a conventional safe driving support device, when a preceding vehicle exists in front of the own vehicle, the inter-vehicle distance from the preceding vehicle is measured so that the own vehicle does not collide with the preceding vehicle, and the measured inter-vehicle distance is When it is less than the predetermined threshold value, a predetermined safe driving support process (for example, outputting a warning sound or applying a brake) is performed.

  FIG. 9 is a diagram illustrating a positional relationship of the vehicle for explaining the operation of the safe driving support apparatus according to the related art. In the example shown in FIG. 9, the host vehicle C is traveling in the left lane 902 and the preceding vehicle D is traveling in the right lane 904. That is, the host vehicle C and the preceding vehicle D are traveling on different lanes. In the example shown in FIG. 9, the host vehicle C is traveling on a straight road in the left lane 902, and the preceding vehicle D is traveling on the left curved road in the right lane 904, so that the preceding vehicle D is It is in the state located in front of. In this case, it is considered that the possibility that the own vehicle C collides with the preceding vehicle D is low. Nevertheless, the conventional safe driving support device has a problem in that when the inter-vehicle distance between the host vehicle C and the preceding vehicle D is less than a predetermined threshold, a predetermined safe driving support process is performed.

  In the technology disclosed in Patent Document 1, when it is determined that the preceding vehicle is traveling on a curved road, the estimated inter-vehicle distance is corrected. For this reason, when the technique disclosed in Patent Document 1 is applied to the safe driving support device, as described above, even if the preceding vehicle is traveling on a curved road in a lane different from the own vehicle, the corrected inter-vehicle distance If the distance is less than a predetermined threshold, a predetermined safe driving support process is performed.

  Further, in the technology disclosed in Patent Document 1, when it is determined that the preceding vehicle and the host vehicle are traveling on different lanes, the possibility that the preceding vehicle and the host vehicle collide is low. The distance is not estimated. However, in the technique disclosed in Patent Document 1, it is determined whether the preceding vehicle and the host vehicle are traveling in the same lane based on the amount of deviation of the tail lamp of the preceding vehicle with respect to the vehicle width direction of the host vehicle. Like to do. For this reason, as shown in FIG. 9, when the own vehicle C is traveling in the left lane 902 and the preceding vehicle D is traveling in the right lane 904, at least one of the tail lamps D <b> 1 and D <b> 2 of the preceding vehicle D is When the vehicle width W is within the vehicle width W (or when the deviation amount of the host vehicle C from the vehicle width W is less than the threshold value), it is determined that the preceding vehicle D and the host vehicle C are traveling in the same lane. Resulting in. Therefore, when the inter-vehicle distance between the host vehicle C and the preceding vehicle D is less than a predetermined threshold value, a predetermined safe driving support process is performed.

  The present invention has been made to solve such a problem, and can avoid performing a predetermined safe driving support process even though the possibility that the own vehicle collides with a preceding vehicle is low. The purpose is to do so.

  In order to solve the above-described problems, the present invention estimates the inter-vehicle distance from the preceding vehicle, recognizes the wheel of the preceding vehicle from the image in front of the vehicle imaged by the in-vehicle camera, and estimates the inter-vehicle distance. A predetermined safe driving support process is performed according to the image recognition result of the wheel. In particular, in the present invention, even when the estimated inter-vehicle distance is less than a predetermined threshold value, when the four wheels or the side surfaces of the wheels are image-recognized, the predetermined safe driving support process is not performed. I have to.

  According to the present invention configured as described above, when the preceding vehicle is traveling on a curved road having a different lane from the own vehicle in front of the own vehicle, the preceding vehicle is inclined laterally with respect to the own vehicle. The vehicle-mounted camera of the host vehicle captures an image in which four wheels or the side surfaces of the wheels are projected. For this reason, when such an image is recognized for the preceding vehicle, the predetermined safe driving support process can be prevented from being performed regardless of the inter-vehicle distance from the preceding vehicle. Therefore, according to the present invention, it is possible to avoid performing the predetermined safe driving support process even though the possibility that the own vehicle collides with the preceding vehicle is low.

It is a block diagram which shows the function structural example of the safe driving assistance apparatus which concerns on 1st Embodiment of this invention. It is a flowchart which shows an example of the process by the safe driving assistance apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the positional relationship of the vehicle for demonstrating operation | movement by the safe driving assistance apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows an example of the image ahead of the vehicle imaged with the vehicle-mounted camera which concerns on 1st Embodiment of this invention. It is a figure which shows the positional relationship of the vehicle for demonstrating operation | movement by the safe driving assistance apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the function structural example of the safe driving assistance apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows an example of the process by the safe driving assistance apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows an example of the image ahead of the vehicle imaged with the vehicle-mounted camera which concerns on 2nd Embodiment of this invention. It is a figure which shows the positional relationship of the vehicle for demonstrating operation | movement by the safe driving assistance apparatus which concerns on a prior art.

[Functional configuration example of the safe driving support device 10]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a functional configuration example of a safe driving support apparatus 10 according to the first embodiment of the present invention. A safe driving support apparatus 10 illustrated in FIG. 1 is an in-vehicle apparatus mounted on a vehicle (hereinafter, referred to as “own vehicle”). The safe driving support device 10 includes a speaker 10a. The safe driving support device 10 is connected to an in-vehicle camera 20 that captures an image in front of the host vehicle. This safe driving support device 10 recognizes the distance between the vehicle traveling ahead of the host vehicle (hereinafter referred to as “preceding vehicle”) and the image of the wheel of the preceding vehicle in the image captured by the in-vehicle camera 20. Depending on the result, a warning sound for alerting the driver of the inter-vehicle distance can be output from the speaker 10a.

  As shown in FIG. 1, the safe driving support apparatus 10 of this embodiment includes an image acquisition unit 11, a preceding vehicle recognition unit 12, an inter-vehicle distance estimation unit 13, a wheel recognition unit 14, and a warning unit 15 as functional configurations. ing.

  Each of the functional blocks 11 to 15 can be configured by any of hardware, DSP (Digital Signal Processor), and software. For example, when configured by software, each of the functional blocks 11 to 15 is actually configured by including a CPU, RAM, ROM, and the like of a computer, and stored in a recording medium such as a RAM, ROM, hard disk, or semiconductor memory. Is realized by operating.

  The image acquisition unit 11 acquires an image ahead of the host vehicle captured by the in-vehicle camera 20. For example, the in-vehicle camera 20 continuously captures images in front of the host vehicle at a predetermined interval. The image acquisition part 11 acquires the said image from the vehicle-mounted camera 20 whenever the vehicle-mounted camera 20 images the image ahead of the own vehicle.

  The preceding vehicle recognition unit 12 recognizes an image of the preceding vehicle traveling in front of the host vehicle from the image acquired by the image acquisition unit 11. As a method for recognizing the preceding vehicle from the image, various conventionally known methods can be used. For example, the preceding vehicle recognizing unit 12 is stored in advance in the image acquired by the image acquiring unit 11. When the body of the preceding vehicle is detected based on the feature point (for example, body shape), the image including this body is recognized as the preceding vehicle. Furthermore, the recognition accuracy of the preceding vehicle may be improved by detecting a window glass, a tail lamp, or the like.

  The inter-vehicle distance estimation unit 13 estimates the inter-vehicle distance from the preceding vehicle recognized by the preceding vehicle recognition unit 12 from the image acquired by the image acquisition unit 11. Various methods known in the art can be used as the method for estimating the inter-vehicle distance from the image. For example, the inter-vehicle distance from the preceding vehicle is estimated based on the position where the preceding vehicle is shown in the image. The method of doing is mentioned.

  The wheel recognition unit 14 recognizes the wheel of the preceding vehicle recognized by the preceding vehicle recognition unit 12 from the image acquired by the image acquisition unit 11. For example, in the image acquired by the image acquisition unit 11, the wheel recognition unit 14 has predetermined feature points related to wheels (for example, the shape and color of the outer peripheral surface of the tire) below the preceding vehicle recognized by the preceding vehicle recognition unit 12. Etc.) is detected as a wheel.

  When the plurality of wheels of the preceding vehicle image-recognized by the preceding vehicle recognition unit 12 are projected on the image acquired by the image acquisition unit 11, the wheel recognition unit 14 recognizes each of the plurality of wheels. Moreover, the wheel recognition part 14 image-recognizes the side surface of this wheel, when the side surface of the wheel is projected on the image which the image acquisition part 11 acquired. For example, in the image acquired by the image acquisition unit 11, the wheel recognition unit 14 displays an image having predetermined feature points (for example, the shape and color of the tire side surface, the shape and color of the wheel side surface) regarding the wheel side surface. If detected, the image is recognized as the side surface of the wheel.

  The warning unit 15 is an example of a safe driving support processing unit described in the claims. The warning unit 15 is a warning sound for alerting the user of the inter-vehicle distance according to the inter-vehicle distance estimated by the inter-vehicle distance estimation unit 13 and the image recognition result of the wheel of the preceding vehicle by the wheel recognition unit 14 (hereinafter referred to as “warning sound”). , Simply indicated as “warning sound”) from the speaker 10a (an example of a predetermined safe driving support process described in the claims).

  Specifically, the warning unit 15 does not perform a process of outputting a warning sound from the speaker 10a when the inter-vehicle distance estimated by the inter-vehicle distance estimation unit 13 is equal to or greater than a predetermined threshold. Further, the warning unit 15 is configured to detect the wheel recognition when the wheel recognition unit 14 does not recognize the four wheels of the preceding vehicle when the inter-vehicle distance estimated by the inter-vehicle distance estimation unit 13 is less than a predetermined threshold. When the side surface of the wheel of the preceding vehicle is not recognized by the unit 14, a process of outputting a warning sound from the speaker 10a is performed.

  On the contrary, the warning unit 15 is configured such that when the wheel recognition unit 14 recognizes four wheels when the vehicle distance estimated by the vehicle distance estimation unit 13 is less than a predetermined threshold, or the wheel recognition unit 14 When the side surface of the wheel is recognized, the predetermined warning process is not performed.

  In this way, the vehicle wheel 20 captures an image (see FIG. 4) in which the four wheels of the preceding vehicle or the side surfaces of the wheels are projected, as shown in FIG. This is because the preceding vehicle B is inclined in the lateral direction with respect to the host vehicle A by the preceding vehicle B traveling on the curved road. In this case, even if the distance between the preceding vehicle B and the preceding vehicle B is less than the threshold value, the warning unit 15 does not perform the predetermined warning process because the possibility that the own vehicle A will collide with the preceding vehicle B is low.

  In addition, it is preferable to use the threshold according to the vehicle speed of the own vehicle as the threshold value of the inter-vehicle distance. For example, the safe driving support device 10 stores a threshold value for each vehicle speed in the storage unit. In general, the threshold value increases as the vehicle speed increases. The warning unit 15 reads out and uses a threshold value corresponding to the current vehicle speed of the host vehicle from the storage unit. The current vehicle speed of the host vehicle can be specified based on, for example, a vehicle speed signal from a vehicle speed sensor (not shown).

[Example of processing by the safe driving support device 10]
FIG. 2 is a flowchart showing an example of processing by the safe driving support apparatus 10 according to the first embodiment of the present invention. The process illustrated in FIG. 2 is continuously executed by the safe driving support device 10 while the vehicle is traveling, for example.

  First, the image acquisition part 11 acquires the image ahead of the own vehicle imaged with the vehicle-mounted camera 20 (step S202). Next, the preceding vehicle recognition unit 12 performs image recognition of the preceding vehicle traveling ahead of the host vehicle from the image acquired in step S202 (step S204). Here, when the preceding vehicle has not been recognized (step S204: No), the safe driving support device 10 executes the processing subsequent to step S202 again.

  On the other hand, when the preceding vehicle is recognized (step S204: Yes), the wheel recognition unit 14 recognizes the wheel of the preceding vehicle recognized in step S204 from the image acquired in step S202 (step S206). Then, the warning unit 15 determines whether or not the four wheels have been recognized in step S206 (step S208). Here, when it is determined that the four wheels have been image-recognized (step S208: Yes), the safe driving support device 10 executes the processing after step S202 again.

  On the other hand, when it is determined that the four wheels have not been image-recognized (step S208: No), the warning unit 15 determines whether or not the side surface of the wheel has been image-recognized in step S206 (step S210). Here, when it is determined that the image of the side surface of the wheel has been recognized (step S210: Yes), the safe driving support device 10 executes the processing subsequent to step S202 again.

  On the other hand, when it is determined that the image of the side surface of the wheel has not been recognized (step S210: No), the inter-vehicle distance with the preceding vehicle that has been image-recognized in step S204 from the image acquired by the inter-vehicle distance estimation unit 13 in step S202. Is estimated (step S212). Then, the warning unit 15 determines whether or not the inter-vehicle distance estimated in step S212 is less than a predetermined threshold (step S214). Here, when it is determined that the inter-vehicle distance estimated in step S212 is not less than the predetermined threshold value (step S214: No), the safe driving support device 10 executes the processes in and after step S202 again.

  On the other hand, when it is determined that the inter-vehicle distance estimated in step S212 is less than the predetermined threshold (step S214: Yes), the warning unit 15 outputs a warning sound from the speaker 10a (step S216). And the safe driving assistance apparatus 10 complete | finishes a series of processes shown in FIG.

  In the above example, the image of the wheel is recognized first, and when the four wheels or the side surfaces of the wheel are recognized, the inter-vehicle distance is estimated. However, the inter-vehicle distance is estimated first. The wheel image recognition may be performed when the inter-vehicle distance is less than a predetermined threshold.

[Specific example of operation by safe driving support device 10 (first example)]
Next, with reference to FIG. 3 and FIG. 4, the specific example (1st example) of operation | movement by the safe driving assistance apparatus 10 is demonstrated. FIG. 3 is a diagram showing the positional relationship of the vehicle for explaining the operation by the safe driving support apparatus 10 according to the first embodiment of the present invention. In the example shown in FIG. 3, the host vehicle A travels in the left lane 302 and the preceding vehicle B travels in the right lane 304. That is, the host vehicle A and the preceding vehicle B are traveling on different lanes. In the example shown in FIG. 3, the host vehicle A is traveling on the straight road in the left lane 302, and the preceding vehicle B is traveling on the left curved road in the right lane 304. It is in the state located in front of. In this case, it is considered that the possibility that the own vehicle A collides with the preceding vehicle B is low. Therefore, in this case, the safe driving support apparatus 10 of the present embodiment does not perform the process of outputting the warning sound from the speaker 10a regardless of the inter-vehicle distance between the host vehicle A and the preceding vehicle B.

  FIG. 4 is a diagram illustrating an example of an image in front of the vehicle captured by the in-vehicle camera 20 according to the first embodiment of the present invention. An image 400 shown in FIG. 4A and an image 402 shown in FIG. 4B are displayed on the vehicle A when the preceding vehicle B is positioned substantially in front of the vehicle A as shown in FIG. 4 is an image in front of the vehicle captured by the camera 20. In particular, an image 400 shown in FIG. 4A is an image when the preceding vehicle B is traveling on the first half of the left curve road, and an image 402 shown in FIG. It is an image when traveling on the second half of the road.

  As shown in FIG. 4A, when the preceding vehicle B is traveling on the first half of the left curve road ahead of the host vehicle A, the tilt of the preceding vehicle B to the left with respect to the front direction of the host vehicle A is as follows. Is relatively small. For this reason, in the image 400 captured by the vehicle-mounted camera 20, the outer peripheral surfaces (ground contact surfaces) of the left rear wheel B3 and the right rear wheel B4 of the preceding vehicle B are projected, and from the left rear wheel B3 and the right rear wheel B4. The outer peripheral surfaces (ground contact surfaces) of the left front wheel B1 and the right front wheel B2 are projected at a position slightly shifted in the left direction. That is, the four wheels B <b> 1 to B <b> 4 of the preceding vehicle B are shown on the image 400 captured by the in-vehicle camera 20.

  On the other hand, as shown in FIG. 4B, when the preceding vehicle B is traveling on the second half of the curved road, the inclination of the preceding vehicle B in the left direction with respect to the front direction of the host vehicle A becomes relatively large. For this reason, in the image 402 imaged by the vehicle-mounted camera 20, the side surface of the left front wheel B1 of the preceding vehicle B and the side surface of the left rear wheel B3 of the preceding vehicle B are projected.

  As described above, when the preceding vehicle B is traveling on a curved road in front of the host vehicle A, the images 400 and 402 captured by the in-vehicle camera 20 include the four wheels B1 to B4 of the preceding vehicle B or The side surfaces of the wheels B1, B3 of the preceding vehicle B are projected. Therefore, when the side surfaces of the four wheels B1 to B4 or the wheels B1 and B3 are recognized from the images 400 and 402 by the wheel recognition unit 14, the warning unit 15 determines the inter-vehicle distance between the preceding vehicle B and the host vehicle A. Regardless, the warning sound is not output from the speaker 10a. Thereby, the safe driving support device 10 of the present embodiment can avoid the warning sound being output from the speaker 10a even though the possibility that the own vehicle A collides with the preceding vehicle B is low. .

[Specific example of operation by safe driving support device 10 (second example)]
Next, a specific example (second example) of the operation by the safe driving support device 10 will be described with reference to FIG. FIG. 5 is a diagram illustrating the positional relationship of the vehicle for explaining the operation of the safe driving support apparatus 10 according to the first embodiment of the present invention. In the example shown in FIG. 5, both the own vehicle A and the preceding vehicle B are traveling on the left lane 302. In the example shown in FIG. 5, the host vehicle A is traveling on the straight road in the left lane 302 and the preceding vehicle B is traveling on the left curved road in the left lane 302. It is in a state tilted to the left with respect to the front direction.

  In this case, although the preceding vehicle B is traveling in the same lane as the own vehicle A, the image captured by the in-vehicle camera 20 is similar to the images 400 and 402 shown in FIG. There is a possibility that four wheels B1 to B4 or wheels B1 and B3 are projected. In this case, as in the case where the images 400 and 402 are captured, the safe driving support apparatus 10 according to the present embodiment outputs a warning sound from the speaker 10a regardless of the distance between the preceding vehicle B and the host vehicle A. Do not process.

  However, the preceding vehicle B is projected on the image captured by the in-vehicle camera 20 in the same manner as the images 400 and 402. The preceding vehicle B is traveling on a curved road, and the preceding vehicle B and the host vehicle are This is a case where the inter-vehicle distance from A is relatively long. In this case, it is unlikely that the inter-vehicle distance between the preceding vehicle B and the host vehicle A is less than a predetermined threshold. Therefore, in this example, there is no problem caused by not performing the process of outputting the warning sound from the speaker 10a.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. Hereinafter, with respect to the safe driving support apparatus 10 ′ according to the second embodiment, changes from the first embodiment will be described.

[Functional configuration example of safe driving support device 10 ']
FIG. 6 is a block diagram illustrating a functional configuration example of the safe driving support apparatus 10 ′ according to the second embodiment of the present invention. The safe driving support apparatus 10 ′ shown in FIG. 6 is different from that of the first embodiment (FIG. 1) in that it includes a rear surface recognition unit 16 and a warning unit 15 ′ instead of the warning unit 15. Different from the safe driving support device 10.

  The rear surface recognition unit 16 recognizes an image of the rear surface of the preceding vehicle that is shown in the image acquired by the image acquisition unit 11. For example, the rear surface recognition unit 16 is based on feature points (for example, body shape) stored in advance in the image of the preceding vehicle recognized by the preceding vehicle recognition unit 12 in the image acquired by the image acquisition unit 11. When the rear surface of the body of the preceding vehicle is detected, the rear surface of this body is recognized as the rear surface of the preceding vehicle. Furthermore, the recognition accuracy of the rear surface of the preceding vehicle may be increased by detecting a window glass, a tail lamp, or the like.

  The warning unit 15 ′ is a case where the inter-vehicle distance estimated by the inter-vehicle distance estimation unit 13 is less than a predetermined threshold, and when the four wheels of the preceding vehicle are image-recognized by the wheel recognition unit 14, the rear surface When the four wheels recognized by the wheel recognition unit 14 are within the width of the rear surface of the preceding vehicle recognized by the recognition unit 16, a process of outputting a warning sound from the speaker 10a is performed.

  That is, in the first embodiment, when the four wheels of the preceding vehicle are recognized by the wheel recognition unit 14, the warning unit 15 does not perform the process of outputting the warning sound from the speaker 10a. However, even when the preceding vehicle is traveling on the same lane as the own vehicle, when the preceding vehicle is traveling on an uphill road or when the preceding vehicle is a car with a high vehicle height, the in-vehicle camera 20 In the captured image, as shown in FIG. 8, there are cases where four wheels are projected below the body of the preceding vehicle and within the lateral width. In this case, since the preceding vehicle is traveling in the same lane as the own vehicle, if the inter-vehicle distance between the own vehicle and the preceding vehicle is less than the threshold value, the possibility of the own vehicle colliding with the preceding vehicle is high.

  So, in this 2nd Embodiment, even if it is a case where four wheels of a preceding vehicle are image-recognized by the wheel recognition part 14, the preceding vehicle by which the four wheels were image-recognized by the rear surface recognition part 16 When it falls within the width of the rear surface, the warning unit 15 ′ performs a process of outputting a warning sound from the speaker 10a.

[An example of processing by the safe driving support apparatus 10 ′]
FIG. 7 is a flowchart showing an example of processing by the safe driving support apparatus 10 ′ according to the second embodiment of the present invention. The process shown in FIG. 7 continues to be executed by the safe driving support device 10 ′ while the vehicle is traveling, for example. In the process shown in FIG. 7, the changes from the process shown in FIG. 2 are as follows.

  In the process shown in FIG. 7, when it is determined in step S208 that four wheels have been image-recognized (step S208: Yes), the rear vehicle recognition unit 16 projects the preceding vehicle imaged in the image acquired in step S202. An image of the rear surface is recognized (step S209-1). Then, the warning unit 15 ′ determines whether or not the four wheels recognized in the image in step S208 are within the lateral width of the rear surface of the preceding vehicle recognized in step S209-1. S209-2). Here, when it is determined that the four wheels are not accommodated (step S209-2: No), the safe driving support device 10 'executes the processes after step S202 again. On the other hand, when it is determined that the four wheels are accommodated (step S209-2: Yes), the safe driving support device 10 'executes the processing after step S212 (similar to the processing in FIG. 2).

[Specific Example of Operation by Safe Driving Support Device 10 ′]
Next, a specific example (second example) of the operation by the safe driving support apparatus 10 ′ will be described with reference to FIG. FIG. 8 is a diagram illustrating an example of an image in front of the vehicle captured by the in-vehicle camera 20 according to the second embodiment of the present invention. An image 800 shown in FIG. 8 shows that when the preceding vehicle B is traveling in the same lane as the own vehicle A (right lane 304) and the preceding vehicle B is positioned substantially in front of the own vehicle A, the own vehicle A is displayed. It is the image ahead of the vehicle imaged by the in-vehicle camera 20.

  As shown in FIG. 8, when the preceding vehicle B is traveling on a straight road in the same lane as the own vehicle A (right lane 304) in front of the own vehicle A, the preceding vehicle B is in front of the own vehicle A. There is almost no inclination in the horizontal direction. For this reason, the vehicle-mounted camera 20 of the own vehicle A images the preceding vehicle B from behind. In this case, the rear surface Ba of the preceding vehicle B is projected on the image 800 captured by the in-vehicle camera 20, and the outer peripheral surfaces of the left rear wheel B3 and the right rear wheel B4 of the preceding vehicle B are within the lateral width of the rear surface Ba ( The ground plane is projected.

  Here, when the preceding vehicle B is traveling on an uphill road, or when the preceding vehicle B is a vehicle having a high vehicle height, an image captured by the in-vehicle camera 20 is shown on the left rear as shown in FIG. In some cases, the outer peripheral surfaces (ground contact surfaces) of the left front wheel B1 and the right front wheel B2 are projected between the wheel B3 and the right rear wheel B4. This is because the distance between the left front wheel B1 and the right front wheel B2 is shorter than the distance between the left rear wheel B3 and the right rear wheel B4 due to perspective. That is, in the image 800 captured by the in-vehicle camera 20, the four wheels of the preceding vehicle B may be projected within the width of the rear surface Ba of the preceding vehicle B.

  Thus, even when the preceding vehicle B is traveling on a straight road in the same lane as the own vehicle A in front of the own vehicle A, the image 800 captured by the in-vehicle camera 20 shows the preceding vehicle B. The four wheels may be projected within the width of the rear surface Ba of the preceding vehicle B. In such a case, since the preceding vehicle B is traveling in the same lane as the own vehicle A, the own vehicle A collides with the preceding vehicle B when the inter-vehicle distance between the own vehicle A and the preceding vehicle B is less than the threshold value. The possibility increases. Therefore, in the second embodiment, the warning unit 15 ′ determines that the four wheels recognized by the wheel recognition unit 14 are within the lateral width of the rear surface Ba recognized by the rear surface recognition unit 16. In this case, if the inter-vehicle distance estimated by the inter-vehicle distance estimation unit 13 is less than a predetermined threshold, a warning sound is output from the speaker 10a.

  As a result, the safe driving support device 10 ′ of the second embodiment allows the preceding vehicle B to be displayed on the image 800 captured by the in-vehicle camera 20 even though the preceding vehicle B is traveling in the same lane as the host vehicle A. Even if the four wheels have been projected, if the four wheels are within the lateral width of the rear surface Ba of the preceding vehicle B as in this example, the host vehicle A becomes the preceding vehicle B. A warning sound can be output from the speaker 10a as having a high possibility of a collision.

  In each of the above embodiments, the inter-vehicle distance from the preceding vehicle is estimated from the image captured by the in-vehicle camera 20, but the present invention is not limited to this. For example, the inter-vehicle distance from the preceding vehicle may be estimated based on detection signals from various sensors (for example, an ultrasonic sensor and an infrared sensor) mounted on the host vehicle.

  Moreover, in each said embodiment, although a warning sound is output from the speaker 10a as predetermined safe driving assistance processing, it is not restricted to this. For example, the predetermined safe driving support process may be a process of displaying a warning screen on the display or controlling the braking device so that the brake is automatically applied.

  In each of the above embodiments, the image of the preceding vehicle is recognized from the image, and then the wheel of the preceding vehicle is recognized from the image. However, the present invention is not limited to this. For example, the wheels of the preceding vehicle may be recognized from the image without recognizing the preceding vehicle from the image.

  In addition, each of the above-described embodiments is merely an example of a specific example for carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

DESCRIPTION OF SYMBOLS 10,10 'Safe driving assistance apparatus 10a Speaker 11 Image acquisition part 12 Leading vehicle recognition part 13 Inter-vehicle distance estimation part 14 Wheel recognition part 15, 15' Warning part (safety driving assistance processing part)
16 Rear recognition part 20 Car-mounted camera

Claims (4)

An inter-vehicle distance estimating unit that estimates an inter-vehicle distance with a preceding vehicle;
A wheel recognition unit that recognizes an image of a wheel of the preceding vehicle from an image in front of the vehicle imaged by an in-vehicle camera;
A safe driving support processing unit that performs predetermined safe driving support processing according to the inter-vehicle distance estimated by the inter-vehicle distance estimating unit and the image recognition result of the wheel by the wheel recognizing unit;
The safe driving support processing unit, when the inter-vehicle distance estimated by the inter-vehicle distance estimation unit is less than a predetermined threshold, when the four wheel or the side surface of the wheel is image-recognized by the wheel recognition unit. And the predetermined safe driving support process is not performed. A rear surface recognition unit that recognizes an image of the rear surface of the preceding vehicle projected on the image;
The safe driving support processing unit is when the inter-vehicle distance estimated by the inter-vehicle distance estimating unit is less than the predetermined threshold, and when the four wheels are image-recognized by the wheel recognizing unit. 2. The safe driving support process according to claim 1, wherein the predetermined safe driving support process is performed when the four wheels are within a width of the rear surface recognized by the rear surface recognition unit. apparatus. The wheel recognition unit of the safe driving support device recognizes the wheel of the preceding vehicle from the image in front of the vehicle imaged by the in-vehicle camera,
The inter-vehicle distance estimation step in which the inter-vehicle distance estimation unit of the safe driving support device estimates the inter-vehicle distance from the preceding vehicle;
The safe driving support processing unit of the safe driving support device performs a predetermined safe driving support process according to the image recognition result of the wheel in the wheel recognition step and the inter-vehicle distance estimated in the inter-vehicle distance estimation step. A safe driving support processing process to be performed,
In the safe driving support processing step, when the four wheels or the side surfaces of the wheels are image-recognized in the wheel recognition step, the inter-vehicle distance estimated in the inter-vehicle distance estimation step is less than a predetermined threshold value. The safe driving support method is characterized in that the predetermined safe driving support process is not performed. The inter-vehicle distance estimation step in which the inter-vehicle distance estimation unit of the safe driving support device estimates the inter-vehicle distance from the preceding vehicle;
The wheel recognition unit of the safe driving support device recognizes the wheel of the preceding vehicle from the image in front of the vehicle imaged by the in-vehicle camera,
The safe driving support processing unit of the safe driving support device performs predetermined safe driving support processing according to the inter-vehicle distance estimated in the inter-vehicle distance estimating step and the image recognition result of the wheel in the wheel recognizing step. A safe driving support processing process to be performed,
In the safe driving support processing step, when the inter-vehicle distance estimated in the inter-vehicle distance estimation step is less than a predetermined threshold, the four wheels or the side surfaces of the wheels are image-recognized in the wheel recognition step. The safe driving support method is characterized in that the predetermined safe driving support process is not performed.

Images