JP5494728B2 - Approach notification device - Google Patents

Description

  The present invention relates to an approach notification device that notifies a driver of a vehicle of the presence of a moving body that is mounted on a vehicle and approaches from the side in the traveling direction of the vehicle.

  When entering an intersection with poor visibility, the vehicle may collide from the side with a vehicle trying to cross the direction of travel. In order to avoid such a situation, a technology (CTA: Cross Traffic Alert) that detects an object (moving body) approaching the vehicle from the side and notifies the driver of the existence of such a moving body is provided. Has been developed. For example, Patent Document 1 proposes a technique that can detect the presence of a vehicle or a pedestrian approaching the host vehicle from the side by a method in which a blind spot is reduced as much as possible even at an intersection with poor visibility.

  According to the proposed technique, the presence of a vehicle or a pedestrian approaching the host vehicle from the side at an intersection can be notified from the time when the vehicle is in an invisible range. For this reason, it is possible to avoid entering the intersection without noticing the presence of a vehicle approaching from the side and colliding with the encounter.

JP 2010-137767 A

  However, the proposed technique has a problem that the notification may be repeated many times when a plurality of vehicles approach from the side in a connected state.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a technique capable of suppressing an excessive notification of the approach of a vehicle or a pedestrian from the side.

  In order to solve the above-described problem, in the approach notification device of the present invention, when a moving body approaching from the side is detected, an index value for the moving body is acquired, and the index value is used as a notification threshold value. The notification of the approach of the moving body is started by comparing. Furthermore, a mobile body approaching from the side (first mobile body) and a mobile body approaching from the rear of the mobile body (second mobile body) are detected, and notification to the first mobile body is started, and When the difference between the index value for the first moving body and the index value for the second moving body is equal to or less than a predetermined value, the start of notification to the second moving body is prohibited.

In this way, when a plurality of moving bodies approach from the side in a continuous state, the notification is not started for the subsequent moving bodies after the notification is started for the leading moving body. Therefore, it can suppress that alerting | reporting is repeated many times.
The index value for the moving body may be a value determined according to the distance to the moving body. For example, the distance itself may be used as the index value. In addition, the index value is compared with the notification threshold value, and when it is larger, the approach of the moving body is notified, depending on how the index value is determined with respect to the distance. For example, if the distance itself is used as the index value, it is determined that the approach of the moving body is notified when the index value (that is, the distance) is smaller than the notification threshold.

Further, in the approach notification device of the present invention described above, when a moving body is detected on the side, in addition to the distance to the moving body, the speed at which the moving body approaches (approach speed) is measured. May be. And you may make it acquire an index value based on the ratio of the distance to a mobile body, and the approach speed of a mobile body.
The index value may be a value determined by the ratio between the distance to the moving body and the approach speed. For example, the ratio itself may be used as the index value.

  For example, if the moving body approaches at a high speed, it is desirable to notify the approach of the moving body from the stage where the moving body is far away. Conversely, if the moving body is approaching slowly, there is no need to notify the approach so quickly until the moving body approaches. If the index value is acquired based on the ratio between the distance to the moving body and the approaching speed of the moving body, the approach of the moving body can be appropriately notified in consideration of such a case.

  Further, in the approach notification device of the present invention described above, when the difference between the index value for the first moving body and the index value for the second moving body is equal to or less than a predetermined value, the following method is used. It is good also as prohibiting the start of the alerting | reporting with respect to a 2nd moving body. That is, it is good also as prohibiting the start of the alerting | reporting with respect to a 2nd mobile body by extending the alerting | reporting started with respect to the 1st mobile body until the alerting | reporting with respect to a 2nd mobile body is started at least.

  In this way, since the notification is continued even after the first moving body has passed, the driver's attention can be alerted to the approach of the second moving body. Nevertheless, since the notification for the first moving body is only continued, the notification is not repeated as in the case where the notification for the second moving body is started again.

  In the approach notification device of the present invention that extends the notification to the first moving body, the difference between the index value of the first moving body and the index value of the second moving body is equal to or less than a predetermined value as follows. May be detected. First, when a moving body approaching from the side is detected, a collision time obtained by dividing the distance to the moving body by the approach speed is acquired as an index value for the moving body. The remaining notification time started for the first moving body is smaller than the collision time (index value) for the second moving body, and the remaining notification time and the collision time (index value) for the second moving body. If the difference between the index value of the first moving body and the index value of the second moving body is equal to or less than the predetermined value, the notification to the second moving body is started. May be prohibited.

  In this way, after the notification is completed, the notification is not started again in a time shorter than the threshold time. For this reason, even when a some mobile body approaches continuously, it can suppress that alerting | reporting is repeated.

Further, in the approach notification device of the present invention described above, when the difference between the index value for the first moving body and the index value for the second moving body is equal to or less than a predetermined value, the following method is used. It is good also as prohibiting the start of the alerting | reporting with respect to a 2nd moving body. That is, it is good also as prohibiting the start of alerting | reporting with respect to a 2nd moving body by changing a alerting | reporting threshold value in the direction which becomes difficult to alert | report the approach of a moving body.
Note that whether the direction in which the approach of the moving body becomes difficult to be notified is the direction in which the notification threshold is increased or the direction in which the notification threshold is decreased depends on how the index value is determined.

  In this way, after the notification to the first moving body is completed, the notification is not started even if the second moving body approaches. For this reason, even when a some mobile body approaches continuously, it can suppress that alerting | reporting is started many times.

  Or in the approach alerting | reporting apparatus of this invention mentioned above, it is good also as prohibiting the start of alerting | reporting with respect to a 2nd moving body by the following methods. That is, when the difference between the index value for the first moving body and the index value for the second moving body is less than or equal to a predetermined value, the magnitude relationship between the index value for the second moving body and the notification threshold is determined. It is good also as prohibiting the start of the alerting | reporting with respect to a 2nd moving body by not performing.

  Even if it does in this way, after the alerting | reporting with respect to a 1st mobile body is complete | finished, since alerting | reporting will not be started even if a 2nd mobile body approaches, it can suppress starting alerting | reporting many times.

  In addition, in the approach notification device of the present invention that prohibits the start of notification to the second moving body, regardless of the method of extending the notification to the first moving body, the index value of the first moving body is as follows. And the difference between the index value of the second moving body and a predetermined value may be detected. That is, the index value for the second moving body at the time when the first moving body passes forward is acquired. When the index value is smaller than a predetermined determination value, the difference between the index value of the first moving body and the index value of the second moving body is determined to be equal to or less than the predetermined value, and the notification to the second moving body is made. May be prohibited.

  In this way, after the first moving body passes forward, the notification is not started again in a short time corresponding to the determination value. For this reason, it can suppress that alerting | reporting is repeated.

1 is an explanatory diagram showing a configuration of a vehicle 1 on which an approach notification device 10 is mounted. 2 is a block diagram showing a detailed configuration of an approach notification device 10. FIG. It is a flowchart of the side approach alerting | reporting process of 1st Example. It is a flowchart of the notification time extension process which extends notification time in 1st Example. It is explanatory drawing explaining a mode that alerting | reporting time is extended in 1st Example. It is a flowchart of the side approach alerting | reporting process of 2nd Example. It is a flowchart of the notification threshold value change process which changes a notification threshold value in 2nd Example. It is explanatory drawing explaining a mode that an alerting | reporting threshold value is changed in 2nd Example. It is a flowchart of the side approach alerting | reporting process of 3rd Example. It is a flowchart of the re-notification prohibition flag switching process which switches a re-notification prohibition flag in 3rd Example.

Hereinafter, examples will be described in order to clarify the contents of the present invention described above.
A. Device configuration :
FIG. 1 shows a rough configuration of a vehicle 1 equipped with an approach notification device 10 of the present embodiment. The vehicle 1 equipped with the approach notification device 10 is equipped with a front monitoring device 12 at a substantially central position ahead in the traveling direction of the vehicle 1, and a left side monitoring device 14 on the left side of the front monitoring device 12. However, a right side monitoring device 16 is mounted on the right side of the front monitoring device 12.

  The forward monitoring device 12 monitors a predetermined angle range (angle range indicated by hatching in FIG. 1) around the traveling direction of the vehicle 1. As the forward monitoring device 12, any one of an in-vehicle camera, a radar of various wavelengths, a sonar, and the like can be used.

The left side monitoring device 14 monitors the left side with respect to the traveling direction of the vehicle 1 and detects a moving body (a vehicle, a bicycle, a pedestrian, etc.) existing on the left side. Similarly, the right side monitoring device 16 monitors the right side with respect to the traveling direction of the vehicle 1 and detects a moving body present on the right side. In the left side monitoring device 14 and the right side monitoring device 16 of the present embodiment, a highly directional electromagnetic wave such as a millimeter wave radar or a laser radar is emitted in a beam shape, and a predetermined angle range is about 20 to 100 msec. A moving body is detected by scanning at short time intervals. FIG. 1 shows a state in which the left side monitoring device 14 and the right side monitoring device 16 emit beams 14r and 16r, respectively, and scan predetermined angle ranges 14a and 16a.
Note that the left side monitoring device 14 and the right side monitoring device 16 may also be realized by using an in-vehicle camera, radars of various wavelengths, sonar, and the like, similar to the front monitoring device 12. The left side monitoring device 14 and the right side monitoring device 16 of the present embodiment correspond to “side monitoring means” in the present invention.

  The front monitoring device 12, the left side monitoring device 14, and the right side monitoring device 16 are connected to the control device 100. The control device 100 is a computer configured by connecting a CPU, a ROM, a RAM, a timer, and the like so as to be able to read and write data to each other via a bus. When the control device 100 detects that the moving body is approaching from the left side by the output from the left side monitoring device 14, the control device 100 outputs a notification sound from the left speaker 30 provided on the passenger seat side. Further, when the output from the right side monitoring device 16 detects that the moving body is approaching from the right side, a notification sound is output from the right speaker 32 provided on the driver's seat side. For this reason, the presence of the moving body approaching from the side can be notified at the time when it cannot be seen from the driver of the vehicle 1.

  FIG. 2 is a block diagram showing a detailed configuration of the approach notification device 10. As illustrated, the control device 100 is provided with a determination module 102 and a notification module 104. The “module” is an abstract concept in which the control device 100 is divided for the sake of convenience, and the entity of the module is a part of a program, a group of a plurality of programs, or the control device 100. It can be installed hardware or the like.

  A forward monitoring device 12, a left side monitoring device 14, and a right side monitoring device 16 are connected to the determination module 102. The determination module 102 is also connected to a vehicle speed sensor 20, a brake pedal switch 22, and the like. Here, the vehicle speed sensor 20 is a sensor that is mounted on a wheel shaft (not shown) of the vehicle 1 and detects the vehicle speed. The brake pedal switch 22 is a switch that is attached to a brake pedal (not shown) of the vehicle 1 and detects that the brake pedal has been depressed. Instead of the brake pedal switch 22, a position sensor that can detect the amount of depression of the brake pedal can be used.

  The left speaker 30 and the right speaker 32 are connected to the notification module 104. Further, a display monitor 34 mounted on a dashboard (not shown) of the vehicle 1 is also connected to the notification module 104. Based on the output from the devices and sensors, the determination module 102 described above determines whether to notify the presence of a moving body approaching from the side, and outputs the determination result to the notification module 104. The notification module 104 notifies the driver of the vehicle 1 of the presence of the moving body using the left speaker 30, the right speaker 32, or the display monitor 34 according to the determination result from the determination module 102.

  As described above, if such an approach notification device 10 is mounted on the vehicle 1, the presence of a moving body approaching from the side when entering an intersection or the like is not visible to the driver of the vehicle 1. Because it can be notified from, it is convenient to be able to avoid the clash of encounters. However, when approaching in a state where a plurality of vehicles are connected from the side, the notification may be repeated many times and the driver may feel irritated. Therefore, in order to avoid such a concern, the following processing is adopted in the approach notification device 10 of the present embodiment.

B. First Example:
B-1. Side approach notification processing:
FIG. 3 shows a flowchart of the side approach notifying process of the first embodiment for notifying the presence of a moving body approaching from the side. This process is executed by the determination module 102 and the notification module 104 in the control device 100.
When the side approach notification process of the first embodiment is started, the determination module 102 first determines whether or not the vehicle speed of the host vehicle is equal to or lower than the notification speed (S100). Here, the notification speed is a speed for determining whether or not to notify the presence of a moving body approaching from the side. The notification of moving objects assumes that the vehicle speed of the vehicle is below a certain speed because it is assumed that a vehicle or a pedestrian approaches from an area where the driver cannot see when entering the intersection slowly. It may be notified in the case. This constant speed is the notification speed. Further, the vehicle speed of the host vehicle can be detected by the vehicle speed sensor 20 (see FIG. 2). The notification speed is typically set to about 10 km / h.

If the vehicle speed of the host vehicle is equal to or lower than the notification speed (S100: yes), the determination module 102 detects a moving body approaching from the side (S102). The moving body on the left side of the host vehicle can be detected using the left side monitoring device 14, and the moving body on the right side of the host vehicle can be detected using the right side monitoring device 16. When a moving body exists, the distance X to the moving body and the speed at which the moving body approaches the host vehicle (approach speed V) are detected.
Although various known methods can be used as the method for detecting the approach speed V, in this embodiment, a predetermined time (for example, 50 msec) is provided and the distance to the moving body is detected a plurality of times. The approach speed V is detected from the difference between these distances. In addition, when there are a plurality of moving bodies approaching the host vehicle, the distance X and the approach speed V are detected for each moving body.
The processing described below is exactly the same for the moving body detected on the left side of the host vehicle by the left side monitoring device 14 and the moving body detected on the right side of the host vehicle by the right side monitoring device 16. Done in parallel. Therefore, in order to avoid complicated description, the following description will be made without distinguishing between the left side and the right side.

Subsequently, it is determined whether or not a moving body approaching from the side is detected (S104). If a moving object is detected (S104: yes), an index value called a collision time TTC (Time To Collision) is calculated by dividing the distance X obtained for the moving object by the approach speed V. (S106). Here, TTC represents the time required for the vehicle to collide with the host vehicle when approaching with the approach speed V maintained. When a plurality of moving objects are detected, TTC is calculated for each moving object.
In this embodiment, since the determination module 102 calculates the index value, the determination module 102 corresponds to the “index value acquisition unit” in the present invention.

  Thereafter, it is determined whether a notification sound is being output (S108). That is, as will be described later, a notification sound for notifying the presence of a moving body approaching from the side is output over a predetermined standard time. Therefore, there is a case where the approach of the moving body has already been notified in the side approach notification process performed earlier, and the output of the notification sound has been continued. Therefore, in S108, it is determined whether a notification sound is being output. Whether the notification sound is being output is determined separately for the left speaker 30 and the right speaker 32.

As a result, when it is determined that the notification sound is not being output (S108: no), the minimum TTC in the TTC calculated in S106 (or the TTC if only one TTC has been calculated) is predetermined. It is judged whether it is smaller than the notification threshold Th (S110).
Here, the notification threshold value Th is a threshold value used for determining whether or not to notify the approach of the moving body. That is, as described above, the TTC represents the time required for the moving object to collide with the own vehicle. If the TTC is large, there is still time until the moving object collides with the own vehicle. The need to notify the approach of is not high. On the other hand, when TTC is small, the necessity to alert | report the approach of a mobile body becomes high. As is clear from this, an appropriate threshold value is set in advance, and when the TTC becomes smaller than the threshold value, the approach of the moving body may be notified. The notification threshold Th is a threshold for determining whether or not to notify the approach of the moving body by comparing with the TTC as described above.

As a result, when the minimum TTC is smaller than the notification threshold Th (S110: yes), output of the notification sound is started at the standard notification time (S112). That is, when the determination module 102 outputs a command to notify the approach of the moving body to the notification module 104, the notification module 104 receives the standard notification time from the left speaker 30 or the right speaker 32 in accordance with the command from the determination module 102. During this period, output of the notification sound is started. As a result, notification of the approach of the moving body is started. In this embodiment, the standard notification time is set to about 2.5 seconds. In addition to the output of the notification sound, the display monitor 34 may notify the approach of the moving body.
On the other hand, when the minimum TTC is not smaller than the notification threshold Th (S110: no), the notification sound is not output.
Since the determination module 102 determines the magnitude relationship between the minimum TTC and the notification threshold Th, the determination module 102 corresponds to the “magnitude relation determination unit” in the present invention. When the minimum TTC is smaller than the notification threshold Th, the determination module 102 outputs a command to the notification module 104, so that the output of the notification sound is started. Therefore, the determination module 102 also corresponds to “notification start unit” in the present invention.

Thereafter, it is determined whether or not the driving of the host vehicle is finished (S114). Whether or not the operation has ended can be determined by whether or not an IG switch or an engine start switch (not shown) mounted on the vehicle 1 is turned off.
As a result, when it is determined that the operation is not finished (S114: no), the process returns to the head of the side approach notification process, and a series of processes subsequent to S100 is started.

  If it is immediately after the notification of the approach of the moving body is started, in many cases, it is determined that the vehicle speed of the host vehicle is equal to or lower than the notification speed (S100: yes), and the moving body has not yet passed. Is detected (S104: yes), and TTC is calculated again (S106). Thereafter, since it is determined that the notification sound is being output (S108: yes), the notification time extension process is started (S150). As will be described in detail later, in the notification time extension process, when a plurality of moving bodies (such as vehicles) approach in a continuous state, the notification time of the notification sound is extended to a time longer than the standard. As a result, after the notification sound is output to the leading mobile body, the notification sound is not output for the mobile body following the mobile body.

Then, when the notification time extension process (S150) is finished, it is determined whether or not the driving of the host vehicle is finished (S114). As a result, if it is not the end of the operation (S114: no), the process returns to the head of the side approach notification process, and a series of subsequent processes after S100 is started. If the vehicle speed of the host vehicle becomes higher than the notification speed while repeating such processing (S100: no), or if a moving body approaching from the side is not detected (S104: no), the notification is made. The time is set to a standard time (S116). If the notification time has been extended in the notification time extension process (S150) described later, the standard notification time is restored in S116. Thereafter, it is determined whether or not the operation is finished (S114). If the operation is not finished (S114: no), the process returns to S100 again to start the series of processes described above.
On the other hand, when it is determined that the operation is finished (S114: yes), the side approach notification process is finished.

B-2. Notification time extension processing:
FIG. 4 shows a flowchart of the notification time extension process executed in the side approach notification process of the first embodiment. As described above, this process is executed by the determination module 102 in the control device 100 when a moving body approaching from the side is detected and it is determined that the notification sound is already being output.
As shown in FIG. 4, when the notification time extension process (S150) is started, first, the remaining time of the notification sound being output (remaining notification time) is acquired (S152). When the notification sound output is started, the notification time is set to a standard time (see S112 in FIG. 3). Therefore, the elapsed time from the start of the notification sound output is measured by a timer (not shown). The remaining notification time can be obtained by subtracting from the standard notification time.

  Subsequently, it is determined whether or not the obtained remaining notification time is smaller than the minimum TTC (S154). In this embodiment, the standard notification time is set to a time slightly longer than the notification threshold Th (for example, the standard notification time is 2.5 seconds with respect to the notification threshold Th of 2 seconds). For this reason, when the output of the notification sound is started, the notification sound is continued until the moving body that causes the output of the notification sound passes in front of the host vehicle. In other words, the remaining notification time of the notification sound is always longer than the TTC of the moving body that caused the notification sound to be output. From this, the remaining notification time is compared with the minimum TTC, and if the remaining notification time is greater than the minimum TTC (including the same case), the mobile body that has output the notification sound is still It can be determined that the vehicle has not passed in front of the host vehicle. On the contrary, if the minimum TTC is larger than the remaining notification time, the TTC is the TTC obtained for the subsequent moving object, and the moving object that has output the notification sound is already in front of the host vehicle. Can be determined to have passed.

  In S154, for the above reason, it is determined whether or not the remaining notification time is shorter than the minimum TTC (not including the same case). If the remaining notification time is equal to or longer than the minimum TTC (S154: no), the notification time extension process in FIG. 4 is terminated without extending the notification time, and the process returns to the side approach notification process in FIG. To do.

On the other hand, when the remaining notification time is shorter than the minimum TTC (S154: yes), the minimum TTC is considered to be a moving body following the moving body that has caused the notification sound to be output. Therefore, the remaining notification time is subtracted from the minimum TTC (S156), and it is determined whether the obtained calculation time is equal to or shorter than a predetermined threshold time (S158). As a result, when the calculation time is equal to or shorter than the threshold time (S158: yes), the notification to the next moving body is started immediately after the notification that is currently being output is terminated. Therefore, the remaining notification time of the notification currently being output is extended to the minimum TTC (S160).
Note that the threshold time of this embodiment is set to an appropriate value selected between 1 second and 3 seconds. When the remaining notification time is extended in S160, it may be extended slightly longer than the minimum TTC. That is, as described above, the standard notification time is set slightly longer (for example, 0.5 seconds) than the time (TTC) required for the moving body to pass in front of the host vehicle. Therefore, when the remaining notification time is extended, the remaining notification time may be extended longer than the minimum TTC, to the same extent (for example, about 0.5 seconds).

  On the other hand, when the calculation time (= minimum TTC-remaining notification time) obtained in S156 is longer than the threshold time (S158: no), the notification for the next mobile unit is performed after the notification of the current output is terminated. It will take some time to get started. Therefore, in this case, without extending the remaining notification time, the notification time extension process of FIG. 4 is terminated, and the process returns to the side approach notification process of FIG.

  FIG. 5 illustrates a state in which the approach of the moving body is notified by the side approach process of the first embodiment described above. For example, as illustrated in FIG. 5A, it is assumed that two vehicles A and B approaching from the left side are detected when the host vehicle is about to enter an intersection. The distance from the host vehicle is smaller in the vehicle A on the front side than in the vehicle B on the rear side, and the approach speed is substantially the same. Therefore, TTC (= Xa / Va) is the minimum TTC for vehicle A, and in order to notify the approach of vehicle A based on this TTC, output of a notification sound is started in a standard notification time (see S112 in FIG. 3). ).

  Since the vehicle A approaches the host vehicle even after the notification sound starts to be output, the TTC of the vehicle A becomes smaller. However, until the vehicle A passes in front of the host vehicle, it is determined that the minimum TTC (the TTC of the vehicle A) is shorter than the remaining notification time (S154: no in FIG. 4), and the output of the notification sound continues. Is done. FIG. 5B shows how the notification sound is continuously output.

Thereafter, when the vehicle A comes to the front of the host vehicle, the TTC (= Xb / Vb) of the vehicle B traveling behind the vehicle A becomes the minimum TTC. As a result, the minimum TTC (the TTC of the vehicle B) becomes longer than the remaining notification time (S154 in FIG. 4: yes), and this time, the minimum TTC (the TTC of the vehicle B) is longer than the remaining notification time. Is calculated (see S156 in FIG. 4). In the example shown in FIG. 5C, since the vehicle B is traveling immediately behind the vehicle A, the TTC of the vehicle B has already become a small value when the vehicle A comes to the front of the host vehicle. . For this reason, the value obtained by subtracting the remaining notification time from the minimum TTC (TTC of vehicle B) is smaller than the threshold time (S158: yes in FIG. 4), so the remaining notification time is extended (see S160 in FIG. 4). ). As a result, the notification sound started for the vehicle A is continued without being started for the vehicle B.
The remaining notification time is extended to at least the minimum TTC (the TTC of the vehicle B), but may be extended slightly longer (for example, about 0.5 seconds) than the minimum TTC.
Further, as described above, since the notification time for the vehicle A is extended as a result of the notification time for the vehicle B being stopped, the determination module 102 executing the process for extending the notification time is the “notification” in the present invention. Corresponds to “start prohibition means”.

  For the vehicle B, the same processing as that for the vehicle A is performed. That is, until the vehicle B comes in front of the host vehicle, it is determined that the minimum TTC is smaller than the remaining notification time, and the notification is continued as it is. However, when the vehicle B comes in front of the host vehicle, this time, The TTC (= Xc / Vc) of the vehicle C traveling behind the vehicle B is the minimum TTC. As shown in FIG. 5 (d), since the vehicle C travels considerably behind the vehicle B, the value obtained by subtracting the remaining notification time from the minimum TTC (the TTC of the vehicle C) is larger than the threshold time. (S158 in FIG. 4: no). As a result, since the remaining notification time is not extended, the notification sound is temporarily stopped, and then the notification to the vehicle C is made when the vehicle C approaches and the TTC of the vehicle C becomes smaller than the notification threshold Th. Sound output starts.

As described above, in the side approach notification processing of the first embodiment, when a plurality of moving bodies approach continuously like the vehicles A and B, the first approaching body is started. The output of the notification sound is extended, and the output of the notification sound is not started for the subsequent mobile body. For this reason, when a plurality of moving bodies approach successively, the approach is not continuously reported many times, so that the driver does not feel harsh. Further, since the vehicle A and the vehicle B are close to each other, if the vehicle A notices the approach of the vehicle A, the vehicle B notices the approach of the vehicle B at the same time. For this reason, even if it is not notified again, the driver overlooks the approach of the vehicle B and enters the intersection and does not collide with the vehicle B.
On the other hand, as for the relationship between the vehicle B and the vehicle C, the approach of the vehicle (here, the vehicle C) that is far from the preceding vehicle (here, the vehicle B) is notified again. For this reason, it is possible to avoid the collision with the vehicle C by entering the intersection without noticing the approach of the vehicle C after the vehicle B passes.

C. Second embodiment:
In the first embodiment described above, when a plurality of moving bodies are approaching continuously from the side, the notification sound for the leading moving body is extended so that the notification for the subsequent moving body is not started. did. However, the method of not starting the notification for the subsequent moving body is not limited to the method of extending the notification sound. For example, since the output of the notification sound is started when the minimum TTC is smaller than the notification threshold value Th, the notification sound is not started to be output by reducing the notification threshold value Th for the following mobile body. Also good. Hereinafter, such a second embodiment will be described.

C-1. Side approach notification processing:
FIG. 6 shows a flowchart of the side approach notification process of the second embodiment. This process is also executed by the determination module 102 and the notification module 104 in the control device 100.
Also in the side approach notification process of the second embodiment, first, the determination module 102 determines whether or not the vehicle speed of the host vehicle is equal to or lower than the notification speed (S200). If the vehicle speed of the host vehicle is equal to or lower than the notification speed (S200: yes), a moving body approaching from the side is detected (S202). When there are a plurality of moving objects, the distance X and the approach speed V are detected for each moving object.
In the second embodiment, as in the case of the first embodiment described above, the same processing is performed in parallel on the left side and the right side of the host vehicle. Therefore, the left and right sides are not distinguished. To do.

  Subsequently, it is determined whether or not a moving body approaching from the side is detected (S204). If a moving body has been detected (S204: yes), the TTC is calculated by dividing the distance X obtained for the moving body by the approach speed V (S206). When a plurality of moving objects are detected, TTC is calculated for each moving object.

  Thereafter, the notification threshold value changing process is started (S250). Although details of the notification threshold value changing process will be described later, in this process, it is determined whether or not a plurality of moving objects are continuously approaching, and the notification threshold value Th is changed based on the result.

Then, it is determined whether or not the minimum TTC in the TTC calculated in S206 (or TTC if only one TTC has been calculated) is smaller than the notification threshold Th (S208). As a result, when the minimum TTC is smaller than the notification threshold Th (S208: yes), output of the notification sound is started at the standard notification time (S210). In the second embodiment, the notification threshold Th is set to “0” (S212). As described above, the output of the notification sound is started when the minimum TTC is smaller than the notification threshold Th. Therefore, when the notification threshold Th is set to “0”, the output of the notification sound is not started thereafter. It becomes a state. Although the description will be made assuming that the notification threshold value Th is set to “0” here, it may be a sufficiently small value and may not necessarily be “0”.
On the other hand, when the minimum TTC is not smaller than the notification threshold Th (S208: no), the process of starting the output of the notification sound or setting the notification threshold Th to “0” (S210, S212) is omitted. To do.
In the second embodiment, since the notification threshold value Th is set to “0” to prohibit the subsequent notification of the moving body, the determination module 102 is the “notification start prohibiting means” in the present invention. Correspond.

  Thereafter, it is determined whether or not the driving of the host vehicle is finished (S214). As a result, when it is determined that the operation is not finished (S214: no), the process returns to the head of the side approach notification process and starts a series of processes subsequent to S200.

Further, when the vehicle speed of the host vehicle becomes larger than the notification speed (S200: no) or when no moving object approaching from the side is detected (S204: no), the notification threshold value Th is set to a standard value ( S216).
Then, it is determined whether or not the operation is finished (S214). If the operation is not finished (S214: no), the process returns to S200 again to start the series of processes described above.
On the other hand, when it is determined that the operation is finished (S214: yes), the side approach notification process of the second embodiment is finished.

C-2. Notification threshold change processing:
FIG. 7 shows a flowchart of the notification threshold value changing process executed in the side approach notification process of the second embodiment. As described above, this process is executed by the determination module 102 in the control device 100 after a moving body approaching from the side is detected and a TTC for the moving body is calculated (S206 in FIG. 6). The
As shown in FIG. 7, in the notification threshold value changing process (S250), first, it is determined whether or not the notification threshold value Th is set to “0” (S252). As described above, the notification threshold Th is set to “0” when notification to the moving body is started, and when the vehicle speed of the host vehicle exceeds the notification speed or the moving body approaching from the side is not detected, Return to standard value.

  When the notification threshold Th is set to “0” (S252: yes), it is determined whether or not the minimum TTC is larger than the continuous determination value (S254). Here, the continuous determination value is a value for determining whether or not the moving bodies are continuous when there are a plurality of moving bodies. For example, if there is a moving body behind the leading moving body from which the output of the notification sound is started, if the difference between the TTC of the leading moving body and the TTC of the following moving body is small, those movements The body can be considered continuous. Conversely, if the difference in TTC of these mobile objects is large, it can be considered that they are not continuous. The continuity determination value is a threshold value used for determining whether or not a plurality of moving objects are continuous in this way. The continuous determination value may be set to an appropriate value in advance, but in this embodiment, it is set to a value larger than the standard notification threshold Th (typically a value about twice the notification threshold Th). Yes. The continuous determination value in this embodiment corresponds to the “determination value” in the present invention.

  As a result, when it is determined that the minimum TTC is larger than the continuous determination value (S254: yes), the notification threshold value Th is set to a standard value (S256). That is, since the continuous determination value is set to a value larger than the notification threshold value Th, the fact that the minimum TTC is larger than the continuous determination value is nothing less than the notification threshold value Th. Therefore, the TTC is This is considered to be obtained for the moving body behind the moving body for which the output of the notification sound was started. Furthermore, since the TTC is larger than the continuous determination value, it is considered that the moving body from which the TTC is obtained and the preceding moving body are not continuous. In such a case, it is preferable to notify the approach of the moving body again. Therefore, the notification threshold Th is returned to the standard value (S256). Then, the notification threshold value changing process is terminated, and the process returns to the side approach notification process of the second embodiment shown in FIG.

On the other hand, when the minimum TTC is smaller than the continuous determination value (S254: no), it is determined whether or not the brake is turned off (S258). As shown in FIG. 2, since the brake pedal switch 22 is connected to the control device 100, it can be recognized immediately when the brake is turned off.
As a result, if the brake remains off (S258: no), it can be determined that the driver of the host vehicle is waiting for the moving body approaching from the side, so that the notification threshold Th is “0”. The notification threshold value changing process is terminated, and the process returns to the side approach notification process of FIG.
On the other hand, when the brake is turned on (S258: yes), the driver of the own vehicle aims at the cut of the moving body approaching from the side or is not aware of the moving body approaching from the side. It is thought that it is going to enter. Therefore, in this case, the notification threshold value Th is returned to the standard value so that the approach of the moving body can be notified again (S256), the notification threshold value changing process is terminated, and the side approach notification process of FIG. Return.

FIG. 8 illustrates a state in which the approach of the moving body is notified by the side approach process of the second embodiment described above. In the illustrated example, when the own vehicle is about to enter the intersection, three vehicles (vehicles A to C) are approaching continuously from the left side, and four vehicles are slightly spaced from behind. A state in which the eye vehicle D approaches is shown.
In this case, TTC (= Xa / Va) for the leading vehicle A is detected as the minimum TTC, and when this TTC becomes smaller than the notification threshold Th, output of notification sound is started (see S210 in FIG. 6), and The notification threshold Th is set to “0” (see S212 in FIG. 6). For this reason, even if the output of the notification sound for the vehicle A ends, the output of the notification sound for the subsequent vehicles B and C is not started.

  However, there is a space between the vehicle C and the vehicle D. Therefore, when the vehicle C passes in front of the host vehicle and the TTC for the vehicle D is detected as the minimum TTC, it is determined that the minimum TTC is larger than the continuous determination value, and the notification threshold Th is returned to the standard value. (See S254 and S256 in FIG. 7). As a result, when the TTC of the vehicle D becomes smaller than the notification threshold Th, notification to the vehicle D is started.

As described above, in the side approach notification process of the second embodiment, when a plurality of moving bodies approach continuously like the vehicles A to C, the first moving body (vehicle A) is used. However, the notification sound is not output for the following moving bodies (vehicle B and vehicle C). For this reason, since the approach of a mobile body is not alert | reported continuously many times, a driver | operator does not feel harsh. Further, since the vehicles A to C are continuous, if only the approach of the leading vehicle A is notified, the driver of the own vehicle will follow without notifying the approach of the continuous vehicles B and C. You can notice the vehicle. For this reason, there is no possibility that the own vehicle enters the intersection.
On the other hand, for a vehicle such as vehicle D that is far from the preceding vehicle (vehicle C in this case), the approach is notified again. For this reason, it becomes possible to avoid entering the intersection without noticing the approach of the vehicle D after the vehicle C passes.

D. Third embodiment:
In the second embodiment described above, when a plurality of moving bodies are approaching from the side in succession, the notification threshold value Th is reduced when the notification sound for the leading moving body is output ("0" in the above-described embodiment). ) To prevent the following mobile body from being notified. However, the method for preventing the subsequent mobile body from starting notification is not limited to the method for reducing the notification threshold Th. For example, after starting the output of the notification sound for the leading mobile body, the output of the notification sound is not started by not determining whether to output the notification sound for the subsequent mobile body. Anyway. Hereinafter, the third embodiment will be described.

D-1. Side approach notification processing:
FIG. 9 shows a flowchart of the side approach notification process of the third embodiment. In contrast to the side approach notification process of the second embodiment described above with reference to FIG. 6, this process sets the re-notification stop flag to ON instead of setting the notification threshold Th to “0” when a notification sound is output. The setting points are different. Hereinafter, this difference will be briefly described.
Also in the side approach notification process of the third embodiment, it is first determined whether or not the vehicle speed of the host vehicle is equal to or lower than the notification speed (S300). A moving body approaching from is detected (S302).
In the third embodiment, exactly the same processing is performed in parallel on the left side and the right side of the host vehicle as in the case of the second embodiment described above.

  Subsequently, it is determined whether or not a moving body approaching from the side is detected (S304). If a moving body is detected (S304: yes), TTC is calculated for the detected moving body (S306). ). Also in the third embodiment, when a plurality of moving objects are detected, TTC is calculated for each moving object.

  Thereafter, it is determined whether or not the re-notification stop flag is OFF (S308). Here, the re-notification stop flag is a flag that is set to ON when the approach of the moving body is notified. As will be described in detail later, when a plurality of moving bodies approach continuously, the re-notification stop flag is set to ON when notification is started with respect to the leading moving body, and thereafter The flag is kept on until the moving body passes in front of the host vehicle. Then, when the last continuous moving body passes in front of the host vehicle, the re-notification stop flag is returned to OFF.

As a result, when it is determined that the re-notification stop flag is OFF (S308: yes), the minimum TTC in the TTC calculated in S306 (or TTC if only one TTC has been calculated) is the notification threshold. It is determined whether it is smaller than Th (S310). As a result, when the minimum TTC is smaller than the notification threshold Th (S310: yes), the output of the notification sound is started at the standard notification time (S312), and then the re-notification stop flag is set to ON (S314). . Thus, the re-notification stop flag is a flag for remembering that the notification sound has been output.
On the other hand, when the minimum TTC is not smaller than the notification threshold Th (S310: no), the processing (S312 and S314) for starting output of the notification sound and turning on the re-notification stop flag is omitted.

  Thereafter, it is determined whether or not the driving of the host vehicle is finished (S316). As a result, when it is determined that the operation is not finished (S316: no), the process returns to the head of the side approach notification process and starts a series of processes after S300.

If the vehicle speed of the host vehicle is greater than the notification speed (S300: no), or if a moving body approaching from the side is not detected (S304: no), the re-notification stop flag is set to OFF. After that (S318), it is determined whether or not the operation is finished (S316). If the operation is not finished (S316: no), the process returns to S300 again to start the series of processes described above.
On the other hand, when it is determined that the operation is finished (S316: yes), the side approach notification process of the third embodiment is finished.

The processing when the setting of the re-notification stop flag is determined to be OFF in S308 has been described above. However, when the re-notification stop flag is determined to be ON (S308: no), the re-notification stop flag switching process described below is performed. Is started (S350).
In the third embodiment, since the re-notification stop flag is set to ON to prohibit the subsequent start of notification to the moving body, the determination module 102 corresponds to the “notification start prohibition means” in the present invention. To do.

D-2. Re-notification stop flag switching processing:
FIG. 10 shows a flowchart of the re-notification stop flag switching process executed in the side approach notification process of the third embodiment. As described above, after calculating the TTC for a moving body approaching from the side (S306 in FIG. 9), this process is performed when the re-notification stop flag is determined to be ON (S308: no in FIG. 9). It is executed by the determination module 102 in the control device 100.
As shown in FIG. 10, in the re-notification stop flag switching process (S350), first, it is determined whether or not the minimum TTC is larger than the continuous determination value (S352). As described in the notification threshold value changing process of the second embodiment, the continuous determination value is a value for determining whether or not the moving bodies are continuous when there are a plurality of moving bodies. Also in the third embodiment, the continuous determination value is set to a value larger than the standard notification threshold Th (typically a value about twice the notification threshold Th). In the third embodiment, the continuous determination value corresponds to the “determination value” in the present invention.

  As a result, when it is determined that the minimum TTC is larger than the continuous determination value (S352: yes), the re-notification stop flag is set to OFF (S354). Then, the re-notification stop flag switching process is terminated, and the process returns to the side approach notification process of the third embodiment shown in FIG.

On the other hand, when the minimum TTC is smaller than the continuous determination value (S352: no), it is determined whether or not the brake is turned off (S356). As a result, if the brake remains off (S356: no), it can be determined that the driver of the host vehicle is waiting for the moving body approaching from the side, so that the re-notification stop flag is turned on. 9), the re-notification stop flag switching process is terminated, and the process returns to the side approach notification process of FIG.
On the other hand, when the brake is turned on (S356: yes), the driver of the own vehicle aims at the cut of the moving body approaching from the side or is not aware of the moving body approaching from the side. It is thought that it is going to enter. Therefore, in this case, in order to be able to notify the approach of the moving body again, after the re-notification stop flag is turned off (S354), the re-notification stop flag switching process is ended and the side approach in FIG. Return to the notification process.

Even in the third embodiment described above, when a plurality of vehicles approach from the side continuously, it is avoided that the notification is repeated many times and the driver feels uncomfortable. Can do. For example, in the case illustrated in FIG. 8, when the notification sound starts to be output to the leading vehicle A, the re-notification stop flag is set to ON (see S <b> 314 in FIG. 9). As long as the re-notification stop flag is not turned off in the flag switching process, the output of the notification sound is not started.
In the re-notification stop flag switching process, the re-notification stop flag is switched to OFF only when the minimum TTC becomes larger than the continuous determination value (S352: yes in FIG. 10). For this reason, in the example shown in FIG. 8, after the notification sound for the vehicle A is output, the re-notification stop flag is kept ON until the vehicle C reaches the front of the host vehicle. No notification sound is output to C.
Thereafter, when the TTC of the vehicle D is detected as the minimum TTC, the re-notification stop flag is switched to OFF, and output of the notification sound to the vehicle D is started. For this reason, since the approach of a mobile body is not alert | reported continuously many times, a driver | operator does not feel harsh.

  The access notification device 10 of the present invention has been described above, but the present invention is not limited to the above-described various embodiments, and can be implemented in various modes without departing from the scope of the invention.

DESCRIPTION OF SYMBOLS 1 ... Vehicle, 10 ... Approach notification apparatus, 12 ... Forward monitoring apparatus,
14 ... Left side monitoring device, 16 ... Right side monitoring device, 20 ... Vehicle speed sensor,
22 ... Brake pedal switch, 30 ... Left speaker,
32 ... Right speaker 34 ... Display monitor 100 ... Control device
102: Determination module 104: Notification module

Claims (7)

An approach notification device that is installed in a vehicle and notifies the driver of the vehicle of the presence of a moving body that approaches from the side of the traveling direction of the vehicle,
Side monitoring means for monitoring a side with respect to a traveling direction of the vehicle and measuring a distance to the moving body when the moving body is detected;
When the moving body is detected by the side monitoring unit, an index value acquiring unit that acquires a predetermined index value based on a distance to the moving body;
A magnitude relation judging means for judging a magnitude relation between the index value obtained by the index value acquiring means and a predetermined notification threshold;
When the magnitude relationship is a predetermined relationship, notification start means for starting the notification for a predetermined time;
The first moving body that is the moving body approaching from the side and the second moving body that is the moving body approaching from the rear of the first moving body are detected, and the notification to the first moving body is started. And when the difference between the index value for the first moving body and the index value for the second moving body is equal to or less than a predetermined value, the start of the notification to the second moving body is prohibited. An approach notification device comprising: a notification start prohibiting means. The approach notification device according to claim 1,
The side monitoring means is a means for measuring the approach speed at which the moving body approaches in addition to the distance to the moving body when the moving body is detected,
The said indicator value acquisition means is a means which acquires the said index value based on the ratio of the distance to the said mobile body, and the said approach speed of this mobile body. The access notification device according to claim 1 or 2,
The notification start prohibiting means is means for prohibiting the start of the notification for the second moving body by extending the notification for the first moving body until at least the notification for the second moving body is started. There is an approach notification device. The access notification device according to claim 3,
The index value acquisition means is means for acquiring, as the index value, a collision time obtained by dividing a distance to the moving body by the approach speed,
The notification start prohibiting means includes
The remaining time of the notification started for the first moving body is smaller than the collision time for the second moving body, and
When the difference between the remaining time of the notification and the collision time with respect to the second moving body is equal to or less than a predetermined threshold time,
A means for determining that a difference between the index value for the first moving body and the index value for the second moving body is equal to or less than the predetermined value, and prohibiting the start of the notification to the second moving body; Notification device. The access notification device according to claim 1 or 2,
The notification start prohibiting means is a means for prohibiting the start of notification to the second moving body by changing the notification threshold in a direction in which the approach of the moving body is hardly reported. The access notification device according to claim 1 or 2,
The notification start prohibiting means is a means for prohibiting the start of notification to the second moving body by prohibiting the determination of the magnitude relationship for the second moving body. The access notification device according to claim 5 or 6,
The notification start prohibiting means is configured to detect the first movement when the index value obtained for the second moving body when the first moving body passes forward is smaller than a predetermined determination value. An approach notification device that determines that a difference between the index value for the body and the index value for the second moving body is equal to or less than a predetermined value and prohibits the start of the notification for the second moving body.

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