JP5786801B2 - Approaching vehicle detection device and driving support system - Google Patents

Description

  The present invention relates to an approaching vehicle detection device that detects an approaching vehicle to the host vehicle, and a driving support system that supports the driver of the host vehicle based on the detected approaching vehicle.

  2. Description of the Related Art Conventionally, driving support systems that perform various types of support for a driver of a driving vehicle are known. For example, in Patent Document 1 below, another vehicle that is present in a blind area with respect to the own vehicle such as an intersection is detected, and the presence of an approaching vehicle when the other vehicle is an approaching vehicle to the own vehicle. Is disclosed to warn the driver.

JP 2000-098015 A

  Here, when the traveling road (cross road) of the approaching vehicle has a gradient, the approaching speed of the approaching vehicle varies depending on the magnitude and direction of the gradient. May delay the approaching vehicle detection time. For example, when the approaching vehicle is approaching an intersection while going down a downhill road, the approaching vehicle is faster than a flat road, and the approaching vehicle may approach the intersection or near the intersection when entering the intersection. The vehicle detection time may be delayed. Then, the delay in the detection time may reduce the accuracy of the support when the driver of the own vehicle is supported based on the positional relationship between the own vehicle and the approaching vehicle.

  SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an approaching vehicle detection device and a driving support system that can improve the disadvantages of the conventional example and can detect an approaching vehicle that may approach the host vehicle at an early stage.

  In order to achieve the above object, an approaching vehicle detection device according to the present invention includes a sound source detection unit that detects a sound source on an intersection road ahead of the own vehicle, and a sound source height that estimates a height position of the sound source relative to the own vehicle. An approaching vehicle determination unit that determines whether or not the sound source is an approaching vehicle with respect to the own vehicle, and when the height position of the sound source is higher than the own vehicle, the own vehicle and the sound source Compared to the case where the sound source is at the same height or the height position of the sound source is lower than the own vehicle, the sound source is in or near the intersection when entering the intersection ahead of the own vehicle. It is easy to determine that the vehicle is an object approaching vehicle that may exist in the vehicle.

  In order to achieve the above object, the driving support system according to the present invention includes a sound source detection unit that detects a sound source on an intersection road ahead of the own vehicle, and a sound source height that estimates a height position of the sound source with respect to the own vehicle. An approach estimation unit; an approaching vehicle determination unit that determines whether or not the sound source is an approaching vehicle to the own vehicle; and a driving support control unit that supports a driver of the own vehicle based on a determination result of the approaching vehicle determination unit; , And when the height position of the sound source is higher than the own vehicle, the own vehicle and the sound source are at the same height, or the height position of the sound source is lower than the own vehicle. Compared to the case, it is easier to determine that the sound source is a target approaching vehicle that may exist in or near the intersection when entering the intersection ahead of the vehicle. It is characterized by.

  Here, if it is determined that the sound source is the target approaching vehicle when the sound information regarding the sound source is equal to or greater than a predetermined determination threshold, the height position of the sound source is higher than the own vehicle. It is desirable that the determination threshold is made small so that it is easy to determine that the sound source is the target approaching vehicle.

  In addition, when dividing sound information related to the sound source and determining whether the sound source is the target approaching vehicle using an added value of power of each divided frequency band, the height position of the sound source Is higher than the own vehicle, the high frequency side of each of the divided frequency bands is weighted more than the low frequency side, thereby determining that the sound source is the target approaching vehicle. It is desirable to make it easy to break.

  In addition, when the height position of the sound source is lower than the own vehicle, the sound source is weighted on the low frequency side of the divided frequency bands more than the high frequency side, so that the sound source is the target approaching vehicle. It is desirable to make it easier to determine that

  Furthermore, in order to achieve the above object, an approaching vehicle detection device according to the present invention includes a sound source detection unit that detects a sound source on an intersection road ahead of the host vehicle, and a relative power of sound information related to the sound source. Is divided into components containing strong frequency components, and the sum of the powers of the divided frequency bands is used to allow the sound source to enter the intersection in front of the vehicle or the intersection of the intersection. An approaching vehicle determination unit that determines whether or not the vehicle is a target approaching vehicle that may exist in the vicinity, and when the distribution of the strong frequency component exists on the high frequency side, each of the divided vehicles In this frequency band, the high frequency side is weighted more than the low frequency side, so that the determination that the sound source is the target approaching vehicle is made easier.

  In order to achieve the above object, the driving support system according to the present invention includes a sound source detection unit that detects a sound source on an intersection road ahead of the host vehicle, and a relative power level of sound information related to the sound source. Divide the one that contains a strong frequency component, and use the sum of the power of each of the divided frequency bands, and when the sound source enters the intersection in front of the host vehicle, or near the intersection An approaching vehicle determination unit that determines whether the vehicle is a target approaching vehicle that may exist in the vehicle, and a driving support control unit that supports the driver of the host vehicle based on the determination result of the approaching vehicle determination unit In the case where the distribution of the strong frequency component exists on the high frequency side, the sound source can be applied to the target approaching vehicle by weighting the high frequency side of the divided frequency bands more than the low frequency side. Judgment that it is It is characterized in that so easily Re.

  Here, when the distribution of the strong power frequency component is present on the low frequency side, the sound source can be weighted by weighting the low frequency side of each of the divided frequency bands more than the high frequency side. It is desirable to make it easier to determine that the vehicle is an object approaching vehicle.

  Further, it is desirable that the sound source detection unit can also detect a sound source existing in a blind spot region for the own vehicle.

  The approaching vehicle detection device and the driving support system according to the present invention make it easy to determine that the sound source on the cross road ahead of the subject vehicle is the subject approaching vehicle under a predetermined condition. A target approaching vehicle that may exist in the vicinity of the intersection or in the vicinity of the intersection at the time of approach to the front intersection can be detected at an early stage.

FIG. 1 is a diagram illustrating an example of a vehicle to which an approaching vehicle detection device and a driving support system according to the present invention are applied. 2 is a schematic view of the interior of the vehicle shown in FIG. FIG. 3 is an AA arrow view of FIG. 4 is a detailed view of a portion B in FIG. FIG. 5 is a configuration diagram of a main part of the approaching vehicle detection device and the driving support system according to the present invention. FIG. 6 is an explanatory diagram of the first phase. FIG. 7 is an explanatory diagram of the second phase. FIG. 8 is an explanatory diagram of the third phase. FIG. 9 is an explanatory diagram of the fourth phase. FIG. 10 is a flowchart illustrating the arithmetic processing according to the embodiment. FIG. 11 is a diagram illustrating an example of an acquisition form of sound information from a sound source. FIG. 12 is a diagram illustrating an example in which the power of sound information on the low frequency side is high. FIG. 13 is a diagram illustrating an example in which the power of high-frequency sound information is high. FIG. 14 is a flowchart for explaining the arithmetic processing according to the first modification. FIG. 15 is a diagram for explaining a division form of sound information in the first modification. FIG. 16 is a diagram for explaining a division form of sound information in the first modification. FIG. 17 is a diagram for explaining a division form of sound information in the second modification, and is a diagram showing an example in which the power of sound information on the low frequency side is high. FIG. 18 is a diagram for explaining a division form of sound information in the second modification, and showing an example in which the power of sound information on the high frequency side is high. FIG. 19 is a diagram for explaining a division form of sound information in the second modification and is a diagram illustrating an example in which no feature is found in each frequency band. FIG. 20 is a flowchart for explaining the arithmetic processing according to the second modification.

  Hereinafter, embodiments of an approaching vehicle detection device and a driving support system according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments.

[Example]
Embodiments of an approaching vehicle detection device and a driving support system according to the present invention will be described with reference to FIGS.

  The approaching vehicle detection device is a device that detects a vehicle approaching the host vehicle (an approaching vehicle). The illustrated approaching vehicle detection device is not only an approaching vehicle whose presence can be directly recognized by the imaging device 51 and the like described later, but also in a region that becomes a blind spot for the own vehicle (especially a blind spot region in front of the own vehicle and diagonally forward). It also detects existing approaching vehicles. In addition, the driving support system provides support to the driver of the own vehicle during driving. This exemplary driving support system includes an approaching vehicle detection device and a driving support device, and supports driving of the host vehicle based on the positional relationship between the approaching vehicle and the host vehicle detected by the approaching vehicle detection device. The approaching vehicle detection device and the driving support system control the operation by an electronic control device (hereinafter referred to as “driving support ECU”) 1 for driving support.

  First, the vehicle 100 to which the approaching vehicle detection device and the driving support system are applied will be described. In this vehicle 100, braking / driving force and the like are controlled by an electronic control device (hereinafter referred to as “travel control ECU”) 2 for travel control. The travel control ECU 2 is connected to the driving support ECU 1 and can exchange information and commands between them. Here, an FF (Front engine Front drive) car is taken as an example.

  The vehicle 100 includes an engine 11 such as an internal combustion engine or an external combustion engine as a power source. The engine 11 is controlled by the travel control ECU 2 to output a required engine torque corresponding to the amount of operation (accelerator opening, etc.) of the driver's accelerator pedal 15. The operation amount of the accelerator pedal 15 is detected by an accelerator operation amount detection device 41 such as an accelerator opening sensor. The accelerator operation amount detection device 41 is connected to the travel control ECU 2. Further, the engine 11 can also output the requested engine torque by the travel control ECU 2 controlling the throttle opening degree or the like regardless of the magnitude of the operation amount of the accelerator pedal 15 or the presence or absence of the driver's accelerator operation.

  Here, in this example, only the engine 11 as a mechanical power source is mounted as a power source, but as the power source, an electric power source such as a motor generator may be mounted instead of the engine 11, Both a mechanical power source and an electric power source may be mounted.

  The vehicle 100 also includes a power transmission device including a transmission 12 that transmits the power of the engine 11 to the drive wheels Wfl and Wfr. The transmission 12 may be a stepped or continuously variable automatic transmission controlled by the travel control ECU 2 or a manual transmission in which the shift stage is determined by a manual operation of the driver. In this example, a vehicle speed detection device (vehicle speed sensor or the like) 42 for detecting the vehicle speed based on the rotational speed of the output shaft of the transmission 12 is provided.

  Further, the vehicle 100 includes a braking device 21 that generates a braking force on each wheel W by the hydraulic pressure of the brake fluid, and a brake hydraulic pressure control device as a hydraulic actuator that can control the hydraulic pressure supplied to the braking device 21 for each wheel W. 22. The brake hydraulic pressure control device 22 can output the master cylinder pressure corresponding to the operation amount of the brake pedal 25 as it is, and can increase or decrease the master cylinder pressure according to a command from the travel control ECU 2. Is possible. The operation amount of the brake pedal 25 is detected by a brake operation amount detection device 43 such as a pedal opening sensor. The brake operation amount detection device 43 is connected to the travel control ECU 2. The vehicle 100 can generate a regenerative braking force when it has an electric power source.

  Still further, in this vehicle 100, a steering wheel 31 that is operated when the driver steers the steering wheels Wfl and Wfr, and an electric power steering system interposed between the steering wheel 31 and the steering wheels Wfl and Wfr. (EPS: Electric Power Steering) device 32 is provided. The electric power steering device 32 is controlled by the travel control ECU 2. The vehicle 100 is provided with a steering angle detection device (a steering angle sensor or the like) 44 that detects the steering angle of the steering wheel 31. The steering angle detection device 44 is connected to the travel control ECU 2.

  In the vehicle 100, an environment information detection device that detects environmental information around the host vehicle and the driving assistance ECU 1 form part of the configuration of the approaching vehicle detection device. The environmental information here refers to information on other vehicles (including not only four-wheeled vehicles but also two-wheeled vehicles), information on moving objects such as pedestrians and bicycles, and information on road markings (those drawn on roads such as stop lines). , Information on road signs, information on the traveling path of the own vehicle, information on a road that intersects the traveling path of the own vehicle ahead (hereinafter referred to as “intersection road”), and the like. For example, the vehicle 100 includes an imaging device 51, a sound source detection device 52, and a moving body detection device 53 as an environment information detection device. In addition, in this vehicle 100, map information is stored in order to obtain information on the traveling path of the own vehicle (information such as road shape and road gradient) and information on an intersection road ahead (information such as road shape and road gradient). The map information storage device 54 and the vehicle position detection device 55 are provided as environmental information detection devices. Here, map information and a vehicle position detection device in a car navigation system are used.

  The imaging device 51 may be a device that captures image information within an imaging range, such as a CCD (charge-coupled device) camera, and can detect the detection target within the imaging range where light from the detection target reaches. A direct type sensor may be used. In this vehicle 100, the imaging device 51 is used for detecting environmental information in front of the host vehicle. For this reason, for example, as shown in FIG. 2, the imaging device 51 is disposed on the front part of the roof in the vehicle interior and photographs the front of the vehicle through the front window 101. The detection signal of the imaging device 51 is transmitted to the driving support ECU 1.

  For example, the driving support ECU 1 can analyze the detection signal and the like, and can grasp the contents indicated by the road marking and the road sign. Further, the driving assistance ECU 1 recognizes the presence of a moving body in the imaging range on the traveling road of the own vehicle or the existence of a moving body in the imaging range on the front intersection road based on the detection signal. You can also. At that time, the positional relationship of the moving body with the own vehicle (the direction in which the moving body exists with respect to the own vehicle, the distance between the own vehicle and the moving body, etc.) can also be grasped. In addition, when there is a blind spot area for the host vehicle on the intersection road ahead, the driving assistance ECU 1 uses a detection signal from the imaging device 51 to form a blind spot formation (building) that causes the blind spot area in the imaging range. And the like) (the direction in which the blind spot formation exists with respect to the host vehicle, the distance between the vehicle and the blind spot formation, etc.).

  The sound source detection device 52 is a device that is disposed in the front portion of the vehicle 100 and detects a sound source that exists in front of and in front of the host vehicle. For example, the sound source detection device 52 is a sound collection microphone or the like. The sound source detection device 52 is preferably capable of detecting the direction and position of the sound source relative to the vehicle. For this reason, a plurality of sound source detection devices 52 are arranged on the front bumper or the like of the own vehicle. In the illustration of FIG. 1, a plurality of sound source detection devices 52 are arranged at the front end and corner of the front bumper. The detection signal of the sound source detection device 52 is transmitted to the driving support ECU 1.

  For example, the driving assistance ECU 1 can grasp the direction and position of the sound source with respect to the own vehicle based on the respective detection signals of the sound source detection devices 52. Further, the driving support ECU 1 can grasp the position of the sound source based on each detection signal even if the sound source exists in the blind spot area of the own vehicle. Further, the driving support ECU 1 can grasp the state of the sound source in the blind spot area (for example, whether or not it is a moving body) by repeating the detection.

  The moving body detection device 53 is disposed at the front portion of the vehicle 100, and exists when the front end portion of the own vehicle enters the intersection, and is present at an obliquely forward side of the own vehicle or a side of the front side of the own vehicle. Is a device for detecting This moving body detection device 53 is disposed at the center portion of the front end of the front bumper of the own vehicle, the front grille portion, or the like. The moving body detection device 53 detects a detection target object using detection waves such as electromagnetic waves, infrared rays, and lasers instead of sound like the sound source detection device 52. For this reason, the moving body detection device 53 includes a transmission unit that transmits the detection wave and a reception unit that receives a reflected wave of the detection wave. For example, the moving body detection device 53 is a direct sensor that can detect a detection target in an area where a detection wave reaches. The detection signal of the moving body detection device 53 is transmitted to the driving support ECU 1.

  For example, when driving into the intersection, the driving assistance ECU 1 transmits a detection wave from the transmission unit toward the diagonally forward side of the vehicle or the side of the front side of the vehicle, and receives the reflected wave of the detection wave at the reception unit. When it does, it recognizes that the detection target objects, such as a moving body, exist in the transmission direction of a detection wave.

  In this vehicle 100, the driving support device is a part of the configuration of the driving support system together with the environmental information detection device and the driving support ECU 1 that form the approaching vehicle detection device.

  This exemplary driving assistance device provides assistance to the driver by notifying the driver of predetermined driving assistance information. Therefore, as shown in FIGS. 2 and 3, an alarm device 60 for performing the notification is provided as a driving support device in the vehicle interior. The alarm device 60 is disposed in the vicinity of the lower end portion of the front window 101 on the dashboard 102. The warning device 60 is intended to notify the driver of driving support information by stimulating the driver's vision and / or hearing. For example, as shown in FIG. 4, this exemplary alarm device 60 includes a display unit 61 that displays driving support information, and a buzzer unit 62 that outputs a warning sound corresponding to the driving support information. Driving assistance is provided by stimulating the driver's vision and hearing. This example warning device 60 informs the driver of the presence of an approaching vehicle as driving support information and alerts the driver.

  Also, in this example, when there is a concern about the intersection between the own vehicle and the approaching vehicle, the driving assistance is such that the own vehicle is decelerated by reducing the engine torque or increasing the braking force and avoiding the intersection with the approaching vehicle. It can be carried out. In the case of engine control, the engine 11 and the travel control ECU 2 are driving support devices. In the case of brake control, the brake hydraulic pressure control device 22 and the travel control ECU 2 are driving support devices.

  A mode changeover switch 63 for switching the operation mode of the driving support system is provided in the passenger compartment. This exemplary mode changeover switch 63 can be switched between an auto mode in which the driving support system is automatically operated and a manual mode in which the driver switches on and off of the operation of the driving support system. This mode changeover switch 63 is disposed on the instrument panel 103, for example. The vehicle interior further includes an on / off switch 64 for switching on and off the operation of the driving support system when the manual mode is selected. The on / off switch 64 is disposed on the steering wheel 31, for example.

  The driving assistance ECU 1 operates when the mode changeover switch 63 is in the auto mode or when the on / off changeover switch 64 is on, and operates the driving assistance device based on the surrounding environment of the host vehicle. For example, if there is an intersection ahead of the host vehicle, the driving support ECU 1 notifies the driver of the presence by the alarm device 60, or decelerates the host vehicle by reducing the engine torque or increasing the braking force. In this way, driving assistance is provided. Further, when the own vehicle enters the intersection, the driving support ECU 1 detects the approaching vehicle on the intersection road and the position of the approaching vehicle with respect to the own vehicle, and drives the information about the approaching vehicle with the alarm device 60. Driving assistance is provided by informing the user or by decelerating the vehicle by reducing the engine torque or increasing the braking force.

  The vehicle 100 is provided with a notification lamp 65 on each side surface of the front bumper. The notification lamp 65 is lit to notify the moving body existing obliquely forward of the host vehicle or on the front side of the host vehicle of the presence of the host vehicle.

  In FIG. 5, the principal part block diagram of an approaching vehicle detection apparatus and a driving assistance system is shown.

  The travel control ECU 2 includes an engine control unit 2 a that controls the engine 11, and a brake control unit 2 b that controls the brake hydraulic pressure control device 22.

  The driving support ECU 1 includes an operation mode determination unit 1a that determines an operation mode of driving support control based on the state of the mode switch 63 and the on / off switch 64, an imaging control unit 1b that controls the imaging device 51, and a sound source detection device. A sound source detection unit 1c for controlling 52 and a mobile body detection unit 1d for controlling the mobile body detection device 53. The driving support ECU 1 includes an environment determination unit 1e that determines the surrounding environment of the vehicle based on a detection signal of the environment information detection device, and a driving support control unit 1f that performs driving support according to the surrounding environment. Prepare.

  The driving support system detects an approaching vehicle and approaches the vehicle while switching the environmental information detection device to be controlled (the imaging device 51, the sound source detection device 52, and the moving body detection device 53) according to the position of the host vehicle when entering the intersection. Provide driving assistance for vehicles. For this reason, in this driving support system, a driving support phase is set for each environment information detection device. As the phases, four phases (first to fourth phases) are set according to the own vehicle position when entering the intersection.

  In the first phase, the presence / absence of the intersection 93 is determined based on the road markings displayed on the traveling road 91 of the own vehicle and the display contents of the road signs installed beside the traveling road 91 (FIG. 6). In the first phase, the imaging control unit 1b controls the imaging device 51 to photograph the front of the host vehicle while the host vehicle is traveling. The environment determination unit 1e determines whether or not there is information (such as a temporary stop line 94 on the travel path 91) that can recognize the presence of the intersection 93 ahead of the host vehicle based on the detection signal of the imaging device 51. If there is, it is determined that there is an intersection 93 ahead, and if there is no information, it is determined that there is no intersection 93 ahead.

  When the intersection 93 exists ahead, the driving assistance control part 1f can call a driver | operator's attention by displaying on the display part 61 of the warning device 60 about presence of the intersection 93 ahead. In addition, the driving support control unit 1 f can alert the driver by outputting a warning sound from the buzzer unit 62.

  Furthermore, when the intersection 93 is ahead, the driving support control unit 1f sends a command to the travel control ECU 2 if the vehicle speed of the host vehicle is equal to or higher than a predetermined speed, and decreases the engine torque or increases the braking force. Can also be decelerated. The predetermined speed is, for example, a vehicle speed higher than a slow speed at which the host vehicle cannot be stopped immediately by a driver's brake operation.

  The driving support control unit 1 f determines which of these driving support modes is implemented based on the current traveling state of the host vehicle such as the vehicle speed and the surrounding environment information of the host vehicle acquired by the imaging device 51. Decide based on. Therefore, in the first phase, at least one of all the driving assistance modes is implemented.

  The second phase is a phase that is implemented after the driving support of the first phase is performed, and mainly detects a moving object in the blind spot area on the intersection road 92 by the sound source detection device 52 (FIG. 7). In the second phase, the sound source detection unit 1c controls the sound source detection device 52 while the host vehicle is traveling, and detects the sound of the sound source on the intersection road 92 including the blind spot area. The environment determination unit 1e determines whether or not a moving body exists based on the detection signal of each sound source detection device 52, and if it exists, the direction and position of the moving body with respect to the host vehicle are also determined. judge. In addition, the environment determination unit 1e determines whether or not the moving body is approaching the own vehicle, that is, whether or not the vehicle is an approaching vehicle 97 on the cross road 92.

  When it is determined that the approaching vehicle 97 exists on the front crossing road 92, the driving support control unit 1f alerts the driver by displaying the presence of the approaching vehicle 97 on the display unit 61 of the alarm device 60. can do. In addition, when it can be determined that the approaching vehicle 97 exists in the vicinity of the intersection 93 of the intersection road 92, the driving support control unit 1 f further displays the fact on the display unit 61 of the alarm device 60, thereby further paying attention to the driver. Can be aroused. In addition, the driving support control unit 1 f can alert the driver by outputting a warning sound from the buzzer unit 62.

  Furthermore, when such an approaching vehicle 97 exists, the driving support control unit 1f sends a command to the travel control ECU 2 if the vehicle speed of the host vehicle is equal to or higher than a predetermined speed, and reduces the engine torque or increases the braking force. You can also slow down your vehicle. The predetermined speed is determined by, for example, the vehicle speed and positional relationship between the host vehicle and the approaching vehicle 97, and is set to a vehicle speed at which the host vehicle and the approaching vehicle 97 may cross each other.

  The driving support control unit 1 f determines which of these driving support modes is to be implemented, such as the current traveling state of the host vehicle such as the vehicle speed and the surrounding environment information of the host vehicle acquired by the sound source detection device 52. Decide based on. Therefore, in the second phase, at least one of all the driving assistance modes is implemented.

  The third phase is a phase that is implemented after the driving support of the second phase is executed, and the moving object detection device 53 detects the moving object on the intersection road 92 when the front end portion of the own vehicle enters the intersection 93 ( FIG. 8). In this third phase, there is a blind spot area on the intersection road 92 due to a fence or a building, and even if the front end of the vehicle enters the intersection 93, it is still approaching on the intersection road (including sidewalks) 92 This phase is useful when a vehicle 97, a pedestrian 98, or a moving body such as an approaching bicycle cannot be visually recognized. In the third phase, the moving body detection unit 1d controls the moving body detection device 53 to detect a moving body that exists diagonally forward of the host vehicle or on the side of the front side of the host vehicle. The environment determination unit 1e determines whether or not the moving object exists based on the detection signal of the moving object detection device 53. If the moving object exists, the environment determination unit 1e also determines the direction and position of the moving object with respect to the own vehicle. judge. Moreover, this environment determination part 1e determines whether the moving body is approaching the own vehicle.

  The driving support control unit 1 f can alert the driver by displaying the presence of the moving body on the display unit 61 of the alarm device 60. In addition, the driving support control unit 1 f can alert the driver by outputting a warning sound from the buzzer unit 62.

  In addition, when there is a moving body that approaches the host vehicle, the driving support control unit 1f sends a command to the travel control ECU 2 if the vehicle speed of the host vehicle is equal to or higher than a predetermined speed, thereby reducing engine torque or increasing braking force. You can also decelerate your vehicle. The predetermined speed is determined by, for example, the speed and positional relationship between the vehicle and the moving body, and is set to a vehicle speed at which the vehicle and the moving body may cross each other.

  Furthermore, when the moving object detection device 53 can detect the presence of the moving object, at least the front end portion of the own vehicle can be visually recognized from the moving object on the cross road 92. Accordingly, when the moving body detection device 53 detects the presence of the moving body, the driving support control unit 1f turns on the notification lamp 65 to indicate the presence of the own vehicle as the moving body (the driver of the approaching vehicle 97, the pedestrian). 98, bicycle drivers, etc.) can also provide driving assistance.

  The driving support control unit 1f determines which of these driving support modes is to be implemented, such as the current traveling state of the host vehicle, such as the vehicle speed, and the surrounding environment information of the host vehicle acquired by the moving body detection device 53. Decide based on and. Therefore, in this third phase, at least one of all the driving assistance forms is implemented.

  The fourth phase is a phase that is implemented after the driving support of the third phase is executed. When the own vehicle further enters the intersection 93, the state of the intersection road 92 is determined by the driver's visual recognition and the moving object detection device 53. (FIG. 9). That is, in the fourth phase, the same moving body detection and driving assistance as in the third phase are performed. For example, when the environment determination unit 1e determines that the moving body is close to the host vehicle based on the detection signal of the moving body detection device 53, the driving support control unit 1f controls the alarm device 60 and the like to drive the vehicle. Provide support.

  By the way, when the intersection road 92 in front of the host vehicle has a gradient, the approaching vehicle 97 intersects with the magnitude of the gradient and the direction of the gradient from the intersection 93 to the place where the approaching vehicle 97 exists. The speed when approaching 93 is considered to be different. For example, when the approaching vehicle 97 approaches the intersection 93 while going down a downhill road, the vehicle speed of the approaching vehicle 97 may be higher than that on a flat road. On the other hand, when the approaching vehicle 97 approaches the intersection 93 while going up the uphill road, the vehicle speed of the approaching vehicle 97 may be slower than that on the flat road. Therefore, even if the approaching vehicle 97 is detected at the same position on the intersection road 92 in relation to the own vehicle, depending on the magnitude of the vehicle speed of the approaching vehicle 97, the approaching vehicle 97 may be affected when the own vehicle enters the intersection 93. The vehicle may approach the vicinity of the intersection 93 or may not approach the vicinity of the intersection 93 when the vehicle enters the intersection 93. For example, when the approaching vehicle 97 approaches the intersection 93 while descending a downhill road, the approaching vehicle 97 is closer to the intersection 93 of its own vehicle than when the approaching road 92 is an uphill road or a flat road. The possibility of approaching to the vicinity of the intersection 93 increases.

  Here, since the imaging device 51 and the moving body detection device 53 can recognize the approaching vehicle 97 that is moving from moment to moment, the host vehicle and the approaching vehicle regardless of the presence or absence of the slope of the intersection road 92 ahead. Driving support according to the positional relationship with 97 becomes possible. In particular, in the case of the imaging device 51, the slope of the intersection road 92 can also be grasped from the captured image, so it can be said that it is suitable for execution of driving assistance. However, when there is a blind spot area on the intersection road 92 ahead when viewed from the own vehicle, the approaching vehicle 97 existing in the blind spot area cannot be recognized by the imaging device 51 or the moving body detection device 53, so driving assistance is provided. I can't do it.

  On the other hand, the sound source detection device 52 can also detect a sound source existing in the blind spot area. In this case, it is determined whether or not the sound source is the approaching vehicle 97 based on the sound information of the sound source existing on the front intersection road 92 detected by the sound source detection device 52. This determination may be performed, for example, by providing an approaching vehicle determination unit in the driving assistance ECU 1 and causing the approaching vehicle determination unit to execute the determination. However, since this exemplary driving support ECU 1 is already provided with an environment determination unit 1e for determining the surrounding environment of the vehicle, this determination is performed by the environment determination unit 1e. In this example, since this determination is performed in the second phase, it is considered that the distance between the vehicle position and the intersection 93 at the time of this determination is substantially the same length at various intersections.

  Specifically, the environment determining unit 1e extracts a predetermined frequency component (frequency band) from the sound information detected by the two or more sound source detection devices 52. The predetermined frequency band is determined in advance through experiments and simulations, and corresponds to the frequency band of sound emitted from a running vehicle. A plurality of types of frequency bands may be provided for each type of sound source (moving body).

  In the environment determination unit 1e, for example, when the average value of the power of sound information of each sound source detection device 52 in the predetermined frequency band is equal to or greater than a predetermined threshold value, the presence of a sound source (here, a running vehicle) exists. Can be recognized. The predetermined threshold is for grasping the presence of a sound source (a running vehicle), and can be set in advance, for example, to an average value of the power of sound emitted from a running vehicle in that frequency band. That's fine. In addition, the environment determination unit 1e obtains a phase shift of each sound information detected by each sound source detection device 52, and obtains an azimuth angle of the sound source (running vehicle) with respect to the own vehicle based on the phase shift. . In this example, since map information and own vehicle position information can be obtained as will be described later, the environment determination unit 1e uses the azimuth and the road information of the intersection road 92 and the own vehicle position information from the map information. Based on this, it is possible to determine the direction and position of the sound source (the traveling vehicle) on the intersection road 92 with respect to the own vehicle.

  In this way, the environment determination unit 1e can determine the presence, direction, and position of a vehicle traveling on the front crossing road 92, but determines whether the vehicle approaches or leaves the intersection 93. It is hard to do. For this reason, the environment determination unit 1e may determine whether or not the vehicle is the approaching vehicle 97 by repeating this determination at least twice.

  When the sound source is the approaching vehicle 97, the environment determination unit 1e may be present in the intersection 93 or in the vicinity of the intersection 93 when the approaching vehicle 97 enters the intersection 93 of the own vehicle (hereinafter, referred to as “the approaching vehicle 97”). It is referred to as “target approaching vehicle”). The environment determination unit 1e compares the sound information regarding the sound source (the approaching vehicle 97) with a predetermined determination threshold, and determines that the sound source is the target approaching vehicle if the sound information is equal to or greater than the predetermined determination threshold. To do. For example, the environment determination unit 1e is caused to obtain the similarity X of the sound information (power waveform) of each sound source detection device 52 in the predetermined frequency band. Then, if the similarity X is equal to or higher than the predetermined determination threshold TH, the environment determination unit 1e determines that the approaching vehicle 97 is the target approaching vehicle because the similarity X of each sound information is high. The predetermined determination threshold TH is a threshold for determining whether or not the sound source (the approaching vehicle 97) is the target approaching vehicle. For example, the sound information of each sound source detection device 52 when the sound source is the target approaching vehicle is used. Decide based on the degree of similarity.

  As described above, the environment determination unit 1e can detect the approaching vehicle 97 existing on the intersection road 92 regardless of the presence or absence of the blind spot area of the intersection road 92 ahead. However, the sound source detection device 52 cannot detect information that can be grasped up to the magnitude and direction of the gradient of the intersection road 92 ahead. For this reason, it is difficult to determine whether or not the approaching vehicle 97 is a target approaching vehicle.

  Therefore, the approaching vehicle detection device and the driving support system according to the present embodiment are configured so that road information (at least the road shape and gradient) of the front crossing road 92 can be acquired, and on the crossing road 92 detected by the sound source detection device 52. Estimate the height position of the sound source in the direction of gravity relative to the vehicle. As described above, the road information of the intersection road 92 is acquired using the map information storage device 54 and the own vehicle position detection device 55 (car navigation system) as the environment information detection device. However, when there is no blind spot area in the vicinity of the intersection 93 of the intersection road 92, information on the magnitude and direction of the gradient of the intersection road 92 may be acquired based on the detection signal of the imaging device 51. The estimation may be performed, for example, by providing a sound source height estimation unit in the driving support ECU 1 and causing the sound source height estimation unit to execute the estimation. However, since this exemplary driving support ECU 1 is already provided with an environment determination unit 1e for determining the surrounding environment of the vehicle, this estimation is executed by the environment determination unit 1e.

  Since the environment determination unit 1e can recognize the presence of the sound source on the front intersection road 92 and the direction and position with respect to the own vehicle as described above, the road information of the intersection road 92 and the own vehicle from the recognition information and the map information. Based on the position information, whether the sound source is at the same height position on the intersection road 92 with respect to the own vehicle, or the sound source is higher on the intersection road 92 than the own vehicle. It is possible to recognize whether the sound source exists at a lower position on the intersection road 92 than the own vehicle. That is, the environment determination unit 1e can detect the presence / absence of a gradient between the position where the sound source exists on the intersection road 92 ahead and the intersection 93, the magnitude of the gradient therebetween, and the gradient direction therebetween.

  When the sound source (approaching vehicle 97) on the intersection road 92 exists at a position higher than the own vehicle, the sound source exists at the same height position as the own vehicle or a position lower than the own vehicle. Compared to, the sound source is likely to have moved to the intersection 93 or the vicinity of the intersection 93 when entering the intersection 93 of the own vehicle, so the possibility that the sound source is the target approaching vehicle is high. . For this reason, when the sound source (approaching vehicle 97) on the intersection road 92 exists at a position higher than the own vehicle, the sound source is located at the same height as the own vehicle or from the own vehicle. As compared with the case where the sound source is present at a low position, the calculation process is performed so that the sound source is easily determined to be the target approaching vehicle. Specifically, when the predetermined determination threshold TH when the detected sound source (the approaching vehicle 97) is at the same height as the host vehicle is set to “TH0”, the environment determination unit 1e determines that the sound source is The determination threshold value THα in the case where the vehicle is located higher than the own vehicle is made smaller than the determination threshold value TH0 so that it can be easily determined that the sound source is the target approaching vehicle. On the other hand, the environment determination unit 1e sets the determination threshold THβ when the sound source is present at a position lower than the own vehicle to be larger than the determination threshold TH0, and determines that the sound source is the target approaching vehicle. To make it difficult to do. The respective determination thresholds THα and THβ may be changed according to the magnitude of the gradient of the intersection road 92. For example, the determination threshold value THα is decreased as the gradient of the intersection road 92 is increased. On the other hand, the determination threshold value THβ is increased as the gradient of the intersection road 92 increases. That is, the environment determination unit 1e is more likely to determine that the sound source is the target approaching vehicle as the sound source (the approaching vehicle 97) on the intersection road 92 is located at a higher position than the own vehicle. Alternatively, it may be more difficult to determine that the sound source is the target approaching vehicle as the sound source is located at a position lower than the own vehicle.

  Hereinafter, determination of whether or not a sound source is a target approaching vehicle will be described based on the flowchart of FIG.

  First, the environment determination unit 1e acquires information necessary for this determination (step ST1). Here, sound information detected by each sound source detection device 52, own vehicle position information, map information (at least information on the shape and gradient of the front crossing road 92), captured image information of the imaging device 51, and the like are acquired. This necessary information is stored in, for example, a temporary storage device of the driving support ECU 1.

  Based on the sound information detected by each sound source detection device 52, the environment determination unit 1e determines whether or not a sound source exists on the intersection road 92 ahead (step ST2). At that time, the environment determination unit 1e selects, for example, the above-described predetermined frequency band (frequency band related to the vehicle in motion) from the sound information detected by the sound source detection device 52, and averages the power of the sound information When the value is equal to or greater than the predetermined threshold, it is determined that a sound source is present, and when the average value is smaller than the predetermined threshold, it is determined that no sound source is present. The environment determination unit 1e performs this determination for each sound source detection device 52.

  Here, in order to increase the accuracy of this determination, the environment determination unit 1e receives the determination result only when, for example, the same determination result is obtained from the sound information of two adjacent sound source detection devices 52. You may make it judge that it is a typical determination result. In addition, if the sound information waveforms in the predetermined frequency band of the two adjacent sound source detection devices 52 are similar to the environment determination unit 1e, the calculation processing after the calculation of the average value of the power of the sound information is performed. If each waveform is rejected, it may be determined that the sound source is not present, thereby improving the accuracy of determining the presence or absence of the sound source.

  If the environment determination unit 1e determines that there is no sound source based on the sound information detected by all the sound source detection devices 52, the calculation processing ends.

  On the other hand, if the environment determination unit 1e determines that at least one sound source is present, the direction of the sound source with respect to the vehicle is determined based on sound information detected by at least two sound source detection devices 52 related to the sound source. An angle is obtained (step ST3). As described above, this calculation is performed based on the phase shift of each sound information detected by each sound source detection device 52. FIG. 11 shows an example when a sound source exists on the front right side of the host vehicle.

  The environment determination unit 1e determines whether it is possible to determine the direction of movement of the sound source (step ST4). When the calculation in step ST3 is performed twice or more, if there is a deviation in the azimuth angle of the sound source of each calculation result, it can be determined that the sound source is moving. On the other hand, when the calculation in step ST3 is executed only once, it is difficult to determine whether or not the sound source is moving. For this reason, in step ST4, if the calculation in step ST3 is performed twice or more, it is determined that the moving direction of the sound source can be determined. If the calculation in step ST3 is performed only once, It is determined that the moving direction cannot be determined, and the process returns to, for example, step ST1.

  When determining the moving direction of the sound source, the environment determining unit 1e compares the azimuth angles of the sound sources for at least two cycles, and determines whether or not the sound source is approaching the intersection 93 (step ST5). That is, in this example, it is determined whether or not the sound source is the approaching vehicle 97. Here, when the deviation of each azimuth angle of the sound source indicates an approach to the intersection 93, it is determined that the sound source is approaching the intersection 93. On the other hand, in this step ST5, when the deviation of each azimuth angle of the sound source indicates that the sound source is away from the intersection 93, or when there is no deviation in each azimuth angle of the sound source and the sound source is in a stopped state, It is determined that the vehicle is not approaching the intersection 93. If the sound source is not approaching the intersection 93, the environment determination unit 1e ends the calculation process.

  If the environment determination unit 1e determines that the sound source is approaching the intersection 93, the environment determination unit 1e determines whether the front intersection road 92 where the sound source considered to be the approaching vehicle 97 is a slope (step ST6). ). In this step ST6, it is determined whether or not the intersection road 92 is a slope based on the vehicle position information and the map information. The determination using the vehicle position information or the like is useful, for example, when there is a blind spot area of the cross road 92 in the visible range in front or in the shooting range of the imaging device 51. It can be known whether or not the intersection road 92 is a slope regardless of the presence or absence. In step ST6, when such a blind spot area does not exist, it is also possible to determine whether or not the intersection road 92 is a slope by using the captured image information of the imaging device 51.

  If the intersection road 92 where the sound source exists is not a slope, the environment determination unit 1e proceeds to step ST9 described later, and uses the determination threshold TH0 for a flat road to determine whether the sound source is a target approaching vehicle. Make a decision.

  On the other hand, when the intersection road 92 where the sound source exists is a slope, the environment determination unit 1e determines the direction of the gradient of the intersection road 92 (step ST7). At the time of this determination, the environment determination unit 1e detects the gradient directions of the intersection roads 92 on the right side and the left side of the intersection 93 when viewed from the own vehicle based on the map information and the captured image information of the imaging device 51. This is because the direction of the gradient may be different on both sides of the intersection 93. By this determination, the environment determination unit 1e can grasp whether the sound source goes down the downhill road and approaches the intersection 93 or whether the sound source goes up the uphill road and approaches the intersection 93.

  The environment determination unit 1e changes the determination threshold value TH to the above-described determination threshold value THα for downhill road or the determination threshold value THβ for uphill road according to the direction of the gradient of the intersection road 92 (step ST8).

  The environment determination unit 1e determines whether or not the sound source is a target approaching vehicle (step ST9). In this determination, the environment determination unit 1e obtains the similarity X of sound information (waveform) in a predetermined frequency band of each sound source detection device 52 related to the sound source. Here, the similarity X of each sound information in a predetermined frequency band detected by at least two adjacent sound source detection devices 52 related to the sound source is calculated. When the intersection road 92 where the sound source exists is a flat road, the environment determination unit 1e determines that the sound source is the target approaching vehicle if the similarity X is equal to or higher than the determination threshold TH0 for the flat road. If the similarity X is smaller than the determination threshold TH0, it is determined that the sound source is an approaching vehicle but is not a target approaching vehicle. When the intersection road 92 where the sound source exists is a downhill road, the environment determination unit 1e determines that the sound source is the target approaching vehicle if the similarity X is equal to or greater than the determination threshold THα (<TH0) for the downhill road. If the similarity X is smaller than the determination threshold THα, it is determined that the sound source is an approaching vehicle but not a target approaching vehicle. When the intersection road 92 where the sound source exists is an uphill road, the environment determination unit 1e determines that the sound source is the target approaching vehicle if the similarity X is equal to or higher than the determination threshold THβ (> TH0) for the uphill road. If the similarity X is smaller than the determination threshold THβ, it is determined that the sound source is an approaching vehicle but not a target approaching vehicle.

  As described above, the approaching vehicle detection device and the driving support system according to the present embodiment move on a flat road or an uphill road when there is a sound source that approaches the intersection 93 while descending on the intersection road 92 ahead. However, it is easier to determine that the sound source is the target approaching vehicle than when approaching the intersection 93. Also, this approaching vehicle detection device and driving support system approaches the intersection 93 while moving on a flat road or a downhill road when there is a sound source that is approaching the intersection 93 while climbing on the intersection road 92 ahead. It is more difficult to determine that the sound source is a target approaching vehicle than to do. Therefore, the approaching vehicle detection device and the driving support system can detect the sound source approaching the intersection 93 while descending on the front intersection road 92, after detection, faster than when approaching on a flat road or uphill road. It can be determined that the vehicle is an object approaching vehicle at the timing. Therefore, the driving support system can inform the driver of the determination result more quickly than when approaching on a flat road or uphill road. It is very useful for alerting the driver. Further, this driving support system can obtain the determination result at an earlier timing than when approaching on a flat road or an uphill road, and the vehicle 100 of the vehicle 100 due to a decrease in engine torque when entering the intersection 93 or the like. Since deceleration can be implemented with good responsiveness, the positional relationship between the host vehicle and the target approaching vehicle can be quickly adjusted so that smooth traffic at the intersection 93 is not obstructed.

[Modification 1]
In the embodiment described above, when determining whether or not the sound source corresponds to the target approaching vehicle, the determination threshold TH used for the determination is changed according to the presence or absence of the gradient of the intersection road 92 and the direction of the gradient, When the sound source on the intersection road 92 exists at a position higher than the own vehicle, the sound source may exist in the intersection 93 or in the vicinity of the intersection 93 when the vehicle enters the intersection 93. It is easy to determine that the vehicle is approaching a certain target. This modification is an approach different from this, and makes it easier to determine that the sound source is the target approaching vehicle when the sound source is at a position higher than the own vehicle.

  The approaching vehicle detection device and the driving support system of this modification have the same configuration as that of the above-described embodiment except for the following differences, and the same as the embodiment until step ST7 in FIG. Perform arithmetic processing.

  The environment determination unit 1e (approaching vehicle determination unit) of the present modification uses sound information in the predetermined frequency band A detected by the sound source detection device 52 as a plurality of frequency bands A1, A2,..., An (n ≧ 2). ), And the power of the sound information of each divided frequency band is added to obtain the correlation value P. Then, when the correlation value P is greater than or equal to a predetermined threshold value P0, the environment determination unit 1e determines that the sound source related to the sound information is the target approaching vehicle. As the predetermined threshold P0, a correlation value in a predetermined frequency band A of a sound source that can be a target approaching vehicle may be set.

  Here, when the vehicle 100 climbs the uphill road, in the sound information of the predetermined frequency band A, the power on the low frequency side tends to be stronger than the high frequency side (FIG. 12). This is because in this case, it is highly likely that the engine speed will be higher than that on flat roads or downhill roads, such as when the driver depresses the accelerator, so the engine sound will be the driving sound. This is because it is considered that the power of the low frequency component becomes stronger. On the other hand, when the vehicle 100 descends on a downhill road, in the sound information of the predetermined frequency band A, the power on the high frequency side tends to be stronger than the low frequency side (FIG. 13). This is because, in this case, the driver is likely to go down with the accelerator off, so the engine sound will be lower than that on flat roads and uphill roads, and the power of the high-frequency components will increase. It is.

  Therefore, in this modification, the weights ω1, ω2,..., Ωn for each frequency band A1, A2,..., An are set according to the moving direction of the sound source and the direction of the gradient of the intersection road 92. The weights ω1, ω2,..., Ωn increase as the sound source moves up the slope, and increase as the low frequency side increases while the sound source moves down the slope as the high frequency side increases. To do. This is because it is determined early that the sound source is a target approaching vehicle. Further, the weights ω1, ω2,..., Ωn are all made equal when the sound source is moving on a flat road. When the weights ω1, ω2,..., Ωn are set, the weights ω1, ω2,..., Ωn are 0 or more and 1 or less, and the total of all the weights ω1, ω2,. To be 1.

  In this modification, the correlation value P is obtained by multiplying each power of each frequency band A1, A2,..., An by weights ω1, ω2,. Then, the correlation value P is compared with the threshold value P0. When the correlation value P is equal to or greater than the threshold value P0, it is determined that the corresponding sound source is the target approaching vehicle.

  Hereinafter, the determination of this modified example regarding whether or not the sound source is the target approaching vehicle will be described based on the flowchart of FIG. The calculation process from step ST1 to step ST7 is the same as the calculation process from step ST1 to step ST7 of FIG.

  The environment determination unit 1e determines whether the sound source (the approaching vehicle 97) approaches the intersection 93 while descending the downhill road by determining the direction of the gradient of the front intersection road 92 in step ST7, or the intersection while climbing the uphill road. It is possible to determine whether or not it is approaching 93. Therefore, the environment determination unit 1e proceeds to step ST9, and determines whether or not the sound source is the target approaching vehicle based on the determination result.

  In step ST9, the environment determination unit 1e divides sound information in a predetermined frequency band A detected by each sound source detection device 52 related to the sound source into a plurality of frequency bands A1, A2,..., An (n ≧ 2). To do. Here, each sound information in the frequency band A detected by at least two adjacent sound source detection devices 52 related to the sound source is divided.

  Since the environment determination unit 1e determines whether the sound source is going down the hill or climbing up the road by the determination in step ST7, the weights ω1, ω2,. Decide. As described above, the weights ω1, ω2,..., Ωn are set so that the high frequency side is increased on the downhill road and the low frequency side is increased on the uphill road. In that case, preset weights ω1, ω2,..., Ωn may be read from, for example, a storage device of the driving support ECU 1, and weights ω1, ω2,. , Ωn may be determined. For example, the weights ω 1, ω 2,..., Ωn for the sound source going downhill may be increased as the gradient of the crossing road 92 is larger if they are in the same frequency band. This is because the vehicle speed of the sound source (the approaching vehicle 97) increases as the gradient of the cross road 92 increases. On the other hand, the weights ω1, ω2,..., Ωn for the sound source going up the uphill road may be made smaller as the gradient of the cross road 92 is larger if they are in the same frequency band. This is because the vehicle speed of the sound source (the approaching vehicle 97) decreases as the gradient of the intersection road 92 increases.

  Further, when it is determined in step ST6 that the intersection road 92 is not a slope, the environment determination unit 1e determines weights ω1, ω2,..., Ωn (ω1 = ω2 =... = Ωn) corresponding to the flat road.

  The environment determination unit 1e multiplies the power of sound information of each frequency band A1, A2,..., An by weights ω1, ω2,. FIG. 15 illustrates sound information after multiplication in the frequency band A of a certain sound source detection device 52. In addition, FIG. 16 illustrates sound information after multiplication in the frequency band A of the adjacent sound source detection device 52. These are examples when the sound source is going downhill.

  The environment determination unit 1e adds the powers in the respective frequency bands A1, A2,..., An and weights ω1, ω2,. The value P is obtained. The environment determination unit 1e compares the correlation value P with the threshold value P0. When the correlation value P is equal to or greater than the threshold value P0, the environment determination unit 1e determines that the sound source related to the sound information is the target approaching vehicle. When it is smaller than the threshold value P0, it is determined that the sound source related to the sound information is the approaching vehicle 97 but not the target approaching vehicle.

  As described above, the approaching vehicle detection device and the driving support system according to the present modification can obtain the same effect as that of the embodiment even if the approaching embodiment is replaced with such a determination form. it can. For example, in this approaching vehicle detection device and driving support system, since the high-frequency components of the weights ω1, ω2,..., Ωn are increased when the sound source (the approaching vehicle 97) is descending a downhill road, the correlation value P is It grows early. Therefore, at this time, the target approaching vehicle on the intersection road 92 can be detected at an early stage without changing the determination threshold TH as in the embodiment. Further, in this approaching vehicle detection device and driving support system, since the low frequency components of the weights ω1, ω2,..., Ωn are increased when the sound source (the approaching vehicle 97) is going up the slope, In addition, the correlation value P increases early. For this reason, at this time, it is possible to detect the approaching vehicle 97 ascending early. Therefore, the driving support system can implement driving support early.

  Here, the approaching vehicle detection device and the driving support system of the present modification may be used in combination with the determination mode in the embodiment (that is, determination using the determination threshold TH that can be changed according to the gradient). The accuracy of the determination result as to whether or not the vehicle is an object approaching vehicle is further increased, and the determination result can be obtained earlier.

[Modification 2]
In the approaching vehicle detection device and the driving support system of the embodiment and the modification 1 described above, in order to determine whether the sound source (the approaching vehicle 97) on the front intersection road 92 is the target approaching vehicle, the intersection road Need road information such as 92 grades. For this reason, the approaching vehicle detection device and the driving support system require a device for knowing the gradient of the intersection road 92 such as the map information storage device 54 (car navigation system) and the imaging device 51. The approaching vehicle detection device and the driving support system of the present modification can determine whether or not the sound source on the front intersection road 92 is the target approaching vehicle without using such a device.

  The approaching vehicle detection device and the driving support system of this modification may have the same configuration as that of the above-described embodiment except for the following differences, but the map information storage device 54 and the imaging device 51 are not necessarily required. It is not necessary to have. Further, in the approaching vehicle detection device and the driving support system, it is not necessary to know the height position of the sound source with respect to the own vehicle, and therefore the driving support ECU 1 does not necessarily have to be provided with the sound source height estimation unit.

  The approaching vehicle detection device and the driving support system relate to the sound information by taking in the frequency component with strong power from the sound information detected by the sound source detection device 52 and analyzing the sound information of the frequency component with strong power. It is determined whether the sound source is a target approaching vehicle.

  Specifically, the environment determination unit 1e (approaching vehicle determination unit) of the present modification causes a reference frequency band having a wider bandwidth than a frequency band including a strong power frequency component to be captured. Is preferred. The reference frequency band is preferably determined in advance according to the type of sound source (for example, a four-wheeled vehicle or a two-wheeled vehicle). For example, when the strong frequency component of the power is included in the reference frequency band of the four-wheeled vehicle, the environment determination unit 1e can capture the reference frequency band of the four-wheeled vehicle from the sound information detected by the sound source detection device 52. Good. Note that, as in the case of the embodiment and the first modification, the environment determination unit 1e receives a predetermined frequency band corresponding to the sound source from the sound information detected by the sound source detection device 52 regardless of the strength of the power. Also good.

  When the determination is made by analyzing the sound information of the captured frequency band, the difference in the strength of the engine sound included in the traveling sound of the sound source (the approaching vehicle 97) is used. When the accelerator opening and the throttle opening are large, it is considered that the engine speed is high and the engine sound is mixed with the running sound and the power of the low frequency component is increased compared to the case where the opening is small ( FIG. 12). On the other hand, when the accelerator opening or the throttle opening is small or zero, the engine speed is low and the engine noise mixed with the running sound is lower than when the opening is large. It is considered that the power of the is increased (FIG. 13). In addition, since the illustrated figure becomes almost the same as FIGS. 12 and 13 of the first modification, FIGS. 12 and 13 are used here.

  That is, when a frequency component with strong power is present on the low frequency side (FIG. 17), it can be estimated that the sound source (the approaching vehicle 97) is approaching the intersection 93 during high vehicle speed traveling such as acceleration traveling. The sound source is likely to be a target approaching vehicle. Further, when a frequency component having a strong power is present on the high frequency side (FIG. 18), the sound source (the approaching vehicle 97) is approaching the intersection 93 at a high vehicle speed traveling with the accelerator off, or while descending a downhill road. Since it can be estimated that the vehicle is approaching the intersection 93, it is highly likely that the sound source is the target approaching vehicle. Furthermore, when the frequency component with strong power has substantially the same strength over the entire reference frequency band (predetermined frequency band) and no characteristics can be found (FIG. 19), the sound source (the approaching vehicle 97) It is estimated that the vehicle will reach the intersection 93 later than the two cases, and it is considered that the possibility of being an object approaching vehicle is low.

  Therefore, in this modified example, when a strong frequency component exists on the low frequency side, the weights ω1, ω2,..., Ωn are increased toward the low frequency side so that the sound source is the target approaching vehicle at an early stage. To be judged. Further, when frequency components with strong power are present on the high frequency side, the weights ω1, ω2,..., Ωn are increased toward the high frequency side so that the sound source is determined to be the target approaching vehicle at an early stage. Further, when there is no feature in the frequency component, the weights ω1, ω2,. When the weights ω1, ω2,..., Ωn are set, the respective weights ω1, ω2,..., Ωn are 0 or more and 1 or less, and the total of all the weights ω1, ω2,. To be 1.

  Hereinafter, the determination of this modified example regarding whether or not the sound source is the target approaching vehicle will be described based on the flowchart of FIG.

  The environment determination unit 1e acquires information necessary for this determination (step ST11). Here, the sound information detected by each sound source detection device 52, the vehicle position information, and the like are acquired. This necessary information is stored in, for example, a temporary storage device of the driving support ECU 1.

  Based on the sound information detected by each sound source detection device 52, the environment determination unit 1e determines whether or not a sound source is present on the front intersection road 92 (step ST12). For example, this determination is performed based on whether or not there is a frequency component with relatively strong power in the detected sound information. Here, if there is a strong power frequency component, it is determined that a sound source is present. If there is no strong power frequency component, it is determined that there is no sound source. This determination may be performed in the same manner as in step ST2 of the embodiment or the first modification. The environment determination unit 1e performs this determination for each sound source detection device 52.

  Here, in order to increase the accuracy of this determination, the environment determination unit 1e only receives the determination result from the sound information of the two adjacent sound source detection devices 52, for example, in the final step ST12. You may make it judge that it is a typical determination result.

  If the environment determination unit 1e determines that there is no sound source based on the sound information detected by all the sound source detection devices 52, the calculation processing ends.

  On the other hand, when it is determined that at least one sound source is present, the environment determination unit 1e obtains the azimuth angle of the sound source with respect to the own vehicle (step ST13). This calculation may be performed in the same manner as in step ST3 of the embodiment or the first modification.

  The environment determination unit 1e determines whether or not the determination of the moving direction of the sound source is possible (step ST14), as in step ST4 of the example or the modification 1. Accordingly, in step ST14, it is determined that the direction of movement of the sound source can be determined if the calculation in step ST13 has been performed twice or more, and the movement of the sound source is determined if the calculation in step ST13 has been performed only once. It is determined that the direction cannot be determined, and the process returns to, for example, step ST11.

  If the environment determination unit 1e can determine the moving direction of the sound source, the environment determining unit 1e determines whether or not the sound source is approaching the intersection 93 (step ST15). This calculation may be performed in the same manner as in step ST5 in the embodiment or the first modification. If the sound source is not approaching the intersection 93, the environment determination unit 1e ends the calculation process.

  When the environment determination unit 1e determines that the sound source is approaching the intersection 93, a frequency component having relatively strong power in the bandwidth of the reference frequency band described above is obtained from sound information related to the sound source considered to be the approaching vehicle 97. Obtain (step ST16).

  The environment determination unit 1e determines the weights ω1, ω2,..., Ωn corresponding to the respective frequency bands A1, A2,. Step ST17).

  The environment determination unit 1e determines whether or not the sound source is the target approaching vehicle using the information of the weights ω1, ω2,..., Ωn (step ST18). At that time, as in the first modification, the environment determination unit 1e converts sound information in the reference frequency band detected by each sound source detection device 52 related to the sound source into a plurality of frequency bands A1, A2,. Divide into 2). Here, each sound information in the reference frequency band detected by at least two adjacent sound source detection devices 52 related to the sound source is divided. The environment determination unit 1e multiplies the power of the sound information of the respective frequency bands A1, A2,..., An by the weights ω1, ω2,. A correlation value P related to the sound source detection device 52 is obtained. When the correlation value P is equal to or greater than the threshold value P0, the environment determination unit 1e determines that the sound source related to the sound information is the target approaching vehicle, and when the correlation value P is smaller than the threshold value P0, It is determined that the sound source involved is the approaching vehicle 97 but not the target approaching vehicle.

  As described above, even if the approaching vehicle detection device and the driving support system of the present modification are configured in this way with respect to those of the embodiment and the first modification, they are the same as the first embodiment and the first modification. An effect can be obtained. In particular, in this approaching vehicle detection device and driving support system, it is possible to detect an approaching vehicle early regardless of whether the crossing road 92 where the sound source exists is a slope. In addition, since the approaching vehicle detection device and the driving support system do not require the map information storage device 54 and the imaging device 51 to be mounted on the vehicle, the cost can be reduced as compared with the embodiment and the first modification.

  Here, the approaching vehicle detection device and the driving support system of the present modification may be used in combination with at least one of the determination modes in the embodiment or the modification 1, thereby determining whether the sound source is the target approaching vehicle. The accuracy of the determination result is further increased, and the determination result can be obtained earlier.

1 Driving assistance ECU
DESCRIPTION OF SYMBOLS 1a Operation form determination part 1b Imaging control part 1c Sound source detection part 1d Moving body detection part 1e Environment determination part 1f Driving assistance control part 2 Travel control ECU
2a Engine control unit 2b Brake control unit 11 Engine 22 Brake hydraulic control device 51 Imaging device 52 Sound source detection device 53 Moving object detection device 54 Map information storage device 55 Own vehicle position detection device 60 Alarm device 65 Notification lamp 100 Vehicle W Wheel

Claims (8)

A plurality of sound source detectors for detecting a sound source on an intersection road ahead of the vehicle;
A map information recording device for recording map information;
An automatic position detection device for acquiring information on the traveling path of the own vehicle and information on an intersection road ahead of the own vehicle;
A sound source that estimates the height position of the sound source with respect to the own vehicle based on the map information recorded by the map information recording device, the information on the traveling road acquired by the automatic position detection device, and the information on the intersection road ahead. A height estimation unit;
The similarity in a predetermined frequency band between the power waveforms of the sound output from the sound source detected by each of the plurality of sound source detection units is equal to or greater than a determination threshold value determined according to the estimation result of the sound source height estimation unit. An approaching vehicle determination unit that determines that the sound source is a target approaching vehicle that may exist in or near the intersection when entering the intersection in front of the vehicle;
With
The approaching vehicle determination unit is
When the sound source height estimation unit estimates that the sound source is at a higher position than the own vehicle, when the sound source and the own vehicle are at the same height, or when the sound source is at a lower position than the own vehicle An approaching vehicle detection device characterized in that the determination threshold value is made smaller than that of the approaching vehicle detection device. A sound source detection unit for detecting a sound source on an intersection road ahead of the vehicle;
The power waveform of the sound output from the sound source detected by the sound source detection unit is divided into a plurality of frequency bands, a correlation value obtained by weighting and adding each power of the divided frequency bands is obtained, and the correlation An approaching vehicle determination unit that determines that the sound source is a target approaching vehicle that may exist in or near the intersection when the vehicle enters the intersection in front of the vehicle when the value is equal to or greater than a determination threshold; ,
With
The approaching vehicle determination unit is
If the waveform of the power of the sound output from the sound source frequency side than the low frequency side is large, multiplied by a coefficient to be multiplied to the low frequency side of the power among the divided respective frequency bands on the high frequency side of the power An approaching vehicle detection device , wherein the correlation value is calculated by weighting greater than a coefficient . The approaching vehicle determination unit is
When the low-frequency side is larger than the high-frequency side in the sound power waveform output from the sound source, the low-frequency side power is multiplied by a coefficient that multiplies the high-frequency side power in each of the divided frequency bands. The approaching vehicle detection device according to claim 2 , wherein the correlation value is calculated by performing weighting greater than a coefficient . A sound source detection unit for detecting a sound source on an intersection road ahead of the vehicle;
Dividing the waveform of the power of the sound output from the sound source detected by the sound source detection unit into a plurality of frequency bands , obtaining a correlation value obtained by weighting and adding the power of each of the divided frequency bands, the correlation value When the vehicle is equal to or greater than a determination threshold, the approaching vehicle determination unit that determines that the sound source is a target approaching vehicle that may exist in or near the intersection when entering the intersection ahead of the host vehicle;
With
The approaching vehicle determination unit is
When there is a peak on the high frequency side in the waveform of the power of the sound output from the sound source, the weight for multiplying the power on the high frequency side of each of the divided frequency bands by the weight for multiplying the power on the low frequency side An approaching vehicle detection device that calculates the correlation value by increasing the value . The approaching vehicle determination unit is
When the sound power waveform output from the sound source has a peak on the low frequency side , a weight for multiplying the power on the high frequency side by the weight for multiplying the power on the low frequency side in each of the divided frequency bands The approaching vehicle detection device according to claim 4, wherein the correlation value is calculated by making the value larger than the value . The approaching vehicle determination unit further determines an azimuth angle of the sound source with respect to the own vehicle based on a phase shift of a sound output from the sound source detected by each of the plurality of sound source detection units. Item 6. The approaching vehicle detection device according to any one of Items 1 to 5 . A plurality of sound source detectors for detecting a sound source on an intersection road ahead of the vehicle;
A map information recording device for recording map information;
An automatic position detection device for acquiring information on the traveling path of the own vehicle and information on an intersection road ahead of the own vehicle;
A sound source that estimates the height position of the sound source with respect to the own vehicle based on the map information recorded by the map information recording device, the information on the traveling road acquired by the automatic position detection device, and the information on the intersection road ahead. A height estimation unit;
The similarity in a predetermined frequency band between the power waveforms of the sound output from the sound source detected by each of the plurality of sound source detection units is equal to or greater than a determination threshold value determined according to the estimation result of the sound source height estimation unit. An approaching vehicle determination unit that determines that the sound source is a target approaching vehicle that may exist in or near the intersection when entering the intersection in front of the vehicle;
A driving support control unit for supporting the driver of the own vehicle based on the determination result of the approaching vehicle determination unit;
With
The approaching vehicle determination unit is
When the sound source height estimation unit estimates that the sound source is at a higher position than the own vehicle, when the sound source and the own vehicle are at the same height, or when the sound source is at a lower position than the own vehicle A driving support system characterized in that the determination threshold value is made smaller than that of the driving support system. A sound source detection unit for detecting a sound source on an intersection road ahead of the vehicle;
The power waveform of the sound output from the sound source detected by the sound source detection unit is divided into a plurality of frequency bands, a correlation value obtained by weighting and adding each power of the divided frequency bands is obtained, and the correlation An approaching vehicle determination unit that determines that the sound source is a target approaching vehicle that may exist in or near the intersection when the vehicle enters the intersection in front of the vehicle when the value is equal to or greater than a determination threshold; ,
A driving support control unit for supporting the driver of the own vehicle based on the determination result of the approaching vehicle determination unit;
With
The approaching vehicle determination unit is
If the waveform of the power of the sound output from the sound source frequency side than the low frequency side is large, multiplied by a coefficient to be multiplied to the low frequency side of the power among the divided respective frequency bands on the high frequency side of the power A driving support system characterized in that the correlation value is calculated by weighting larger than a coefficient .

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