JP4508050B2 - Car alarm system - Google Patents

Description

  The present invention relates to an on-vehicle alarm device, and more particularly to an on-vehicle alarm device that issues an alarm to a vehicle driver when the possibility of collision with a front obstacle reaches a predetermined level.

2. Description of the Related Art Conventionally, there has been known a device that issues a collision warning to a vehicle driver when the possibility of collision of the host vehicle with an obstacle ahead of the vehicle reaches a predetermined level (see, for example, Patent Document 1). In this apparatus, it is detected whether or not the driver is looking aside using an image taken by a camera provided in the passenger compartment. Then, when the driver's aside is detected, the predetermined level related to the possibility of collision with a front obstacle for giving a warning to the vehicle driver by speaker output or display display is changed to a small value. For this reason, according to the above-mentioned conventional device, when the vehicle driver looks aside, the above-mentioned collision warning can be output early, and as a result, safety during vehicle travel can be improved. It becomes.
JP 2004-145725 A

  However, in the above conventional apparatus, the alarm is a sound / sound output by a speaker or a display output by a display. Therefore, particularly when the driver is looking aside, an alarm that stimulates the auditory sense or the visual sense is given to the driver. Therefore, there is a possibility that the driver may not be alerted sufficiently to avoid or reduce the collision before the collision.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an in-vehicle alarm device capable of providing an appropriate alarm in accordance with a driver's looking aside before a vehicle collision.

The above-described object is to detect whether or not the line-of-sight direction of the vehicle driver is in the front direction, and when the line-of-sight direction determination means determines that the line-of-sight direction is in the front direction, a forward obstacle On the other hand, when it is determined that the line-of-sight direction is not in the front direction after the possibility of collision with an object has reached a predetermined level, the vehicle driver has not been able to collide with an obstacle ahead of the vehicle before reaching the predetermined level. A first alarm means for providing a first alarm toward the vehicle, wherein the first alarm means causes the first alarm means before the possibility of collision with a front obstacle reaches the predetermined level. After the alarm 1 is started , when the possibility of collision with a front obstacle reaches the predetermined level, the duration of the state where the line-of-sight direction is not in the front direction is determined as the determination result of the line-of-sight direction determination unit. in the case of the time or more The have rows toward the different second alarm to the vehicle driver and the first alarm. If the duration is less than said predetermined time, said duration is equal to or more than the predetermined time the second alarm is achieved by vehicle alarm system comprising a second warning means intends row toward the vehicle driver when.

  In the invention of this aspect, when the vehicle driver's line-of-sight direction is the front direction, the first warning is given to the vehicle driver after the possibility of collision with the front obstacle reaches a predetermined level. In addition, when the vehicle driver's line-of-sight direction is not in the front direction, the first warning is given to the vehicle driver before the possibility of collision reaches a predetermined level, but after the first warning is started. When the duration of the state where the line-of-sight direction is not in the front direction is equal to or longer than the predetermined time, a second alarm different from the first alarm is issued. In such a configuration, when the look-ahead continues even when the look-ahead is started earlier than usual due to the driver's look-ahead before a vehicle collision, the first alert is different from the first alert. Two warnings will be implemented. For this reason, according to the present invention, the driver can easily turn the line of sight to the front by a second warning different from the first warning, and further promote actions for collision avoidance and collision mitigation. Therefore, it is possible to perform an appropriate warning in accordance with the driver's side-by-side state.

  By the way, in the on-vehicle alarm device described above, the second alarm means is configured such that the first alarm starts after the first alarm is started before the possibility of collision with a front obstacle reaches the predetermined level. The second warning may be given to the vehicle driver when the possibility of a collision with a front obstacle is equal to or higher than the predetermined level and the duration is equal to or longer than the predetermined time.

  Further, in the above-described on-vehicle alarm device, the first alarm unit may collide with a front obstacle according to a duration time in which the line-of-sight direction is not in the front direction as a determination result of the line-of-sight direction determination unit. It is good also as providing a timing change means to change the timing which starts a 1st alarm before reaching the said predetermined level.

  In the on-vehicle alarm device described above, the possibility of collision with the front obstacle may correspond to the time until the host vehicle collides with the front obstacle.

  Furthermore, in the above-described on-vehicle alarm device, the first alarm may be a buzzer sounding or an alarm display, and the second alarm may be alarm braking for decelerating the vehicle. The second alarm means may continue the alarm braking for a predetermined period after the alarm braking is started.

  In these inventions, the “front direction” is a direction when the driver generally turns his / her line of sight substantially in the vehicle traveling direction during straight running.

  ADVANTAGE OF THE INVENTION According to this invention, the appropriate warning according to the driver | operator's looking aside state can be performed before a vehicle collision.

  FIG. 1 shows a configuration diagram of an in-vehicle alarm device 10 according to an embodiment of the present invention. The in-vehicle alarm device 10 of the present embodiment predicts a collision between the own vehicle and a preceding vehicle, an oncoming vehicle, an obstacle such as a stationary object existing in front of the own vehicle, and the possibility of the collision becomes relatively high. It is a pre-crash safety (PCS) system that sometimes warns a vehicle driver for collision avoidance or collision mitigation.

  In this embodiment, the on-vehicle alarm device 10 includes an electronic control unit (hereinafter referred to as a PCS-ECU) 12 mainly composed of a computer. The PCS-ECU 12 is connected to an obstacle sensor 14 disposed on a bumper, a front grill or the like at the front end of the vehicle body. The obstacle sensor 14 is composed of, for example, a millimeter wave radar, a laser radar, a camera, or the like, and sends a signal corresponding to an obstacle existing in front of the own vehicle (particularly on the course of the own vehicle) to the PCS-ECU 12. Output. The PCS-ECU 12 detects the presence or absence of a front obstacle based on the output signal of the obstacle sensor 14, detects the distance between the host vehicle and the front obstacle when there is a front obstacle, and Based on the detected distance and the own vehicle speed detected using a vehicle speed sensor or the like, the relative speed between the two is detected.

  The in-vehicle alarm device 10 also includes a camera ECU 16 mainly composed of a computer connected to the PCS-ECU 12 through serial communication. A camera 18 is connected to the camera ECU 16. For example, the camera 18 is disposed on the upper surface of the steering column cover so as to face the vehicle traveling direction and in the direction in which the vehicle driver's head is present, and the vehicle driver's face is almost from the front. Take a picture. For night photography, a lamp that projects infrared rays toward the face of the vehicle driver may be provided.

  The video signal of the camera 18 is supplied to the camera ECU 16. The camera ECU 16 performs binarization processing and feature point extraction processing based on the video signal supplied from the camera 18 to extract an image showing the driver's face, and the driver's face width from the extracted image. And the center line of the face is detected, and the left / right distance ratio of the face shown in the image is calculated from the parameters, and the direction in which the driver's face faces, that is, the angle from the front (hereinafter, the driver is a straight line) When a line of sight is directed in front of the vehicle traveling direction along the traveling lane during traveling, the angle is set to 0 °; Information about the face direction angle of the vehicle driver detected by the camera ECU 16 is supplied to the PCS-ECU 12. Based on the information supplied from the camera ECU 16, the PCS-ECU 12 grasps the face orientation angle θ as the direction in which the vehicle driver turns his line of sight.

  An alarm display 20 and an alarm buzzer 22 are connected to the PCS-ECU 12. The alarm display 20 is, for example, a meter unit provided on an instrument panel in the passenger compartment, and alerts the vehicle driver by displaying an alarm according to a drive command from the PCS-ECU 12 as will be described later. The alarm buzzer 22 is a buzzer alarm provided in the vehicle interior, and alerts the vehicle driver by sounding a buzzer according to a drive command from the PCS-ECU 12 as will be described later.

  A brake device 24 is also connected to the PCS-ECU 12. The brake device 24 has a hydraulic or electric brake actuator that brakes the wheels of the vehicle. When the driver performs a brake operation or when an instruction is issued from the PCS-ECU 12, the brake actuator 24 is provided. To brake the wheels.

  Next, operation | movement of the vehicle-mounted alarm device 10 of a present Example is demonstrated. FIG. 2 is a diagram for explaining the operation of the in-vehicle alarm device 10 according to the present embodiment.

  In this embodiment, when the PCS-ECU 12 detects the presence of a forward obstacle based on the output of the obstacle sensor 14, the distance and relative speed with respect to the forward obstacle and the course of the host vehicle are thereafter determined at regular intervals. Based on the position of the front obstacle with respect to the route and the like, the possibility that the own vehicle will collide with the front obstacle at the present time (collision possibility) is calculated. The shorter the time until the host vehicle collides with the obstacle ahead, the higher the possibility of collision. Therefore, the possibility of collision calculated by the PCS-ECU 12 depends on the distance between the host vehicle and the obstacle ahead and the relative speed between them. The value corresponding to the time obtained by dividing by (collision prediction time) may be used. In this case, the shorter the collision prediction time, the larger the value.

  In general, the vehicle driver makes a predetermined time (for example, 1.8 seconds or 2 seconds) before colliding with a forward obstacle (for example, a stopped vehicle) ahead on the same lane as the host vehicle. In many cases, actions such as a steering operation and a brake operation for avoiding a collision are started by about 30 meters before the speed of 60 km / h. Therefore, it is effective to avoid the collision and reduce the damage by giving a warning and warning to the vehicle driver at an early timing before the collision, but the vehicle driver can take the collision avoiding action described above. Assuming that the driver is warned within a predetermined time, a warning may occur even when the driver is planning to take a collision avoidance action in the near future. It can be annoying and uncomfortable. Therefore, the PCS-ECU 12 determines the possibility of collision that can effectively take collision avoidance action while suppressing the driver from feeling uncomfortable, that is, the time until the collision (for example, 1.8 seconds or 2 seconds). The reference threshold level (reference time t1 until the collision) for starting the alarm is stored in the storage device in advance.

  In addition, when a vehicle collides with the front, the driver looks at the inner mirror, the outer mirror on the driver's seat or on the passenger's seat, the display on the passenger compartment, or the outside of the vehicle for safety confirmation on the left and right sides of the vehicle. Often caused by carelessness due to looking aside. Therefore, in order to avoid collision and reduce damage to the vehicle, when the driver's attention to the front of the vehicle is reduced before the collision, the above warning is given to the vehicle driver at an earlier timing than usual. It is appropriate to do.

  Here, the driver's side look as described above is performed with a certain degree of gaze from the front. Therefore, the PCS-ECU 12 stores in advance in the storage device a threshold value θ0 (for example, ± 15 °) of the face angle for determining whether or not the driver is looking aside to remove the line of sight from the front direction. is doing. The PCS-ECU 12 compares the face orientation angle θ with the threshold value θ0 stored in the storage device every time information on the driver's face orientation angle θ is supplied from the camera ECU 16.

  As a result of the comparison, the PCS-ECU 12 determines that the driver's line of sight is almost in front when the face angle θ is within the threshold value θ0. When the possibility of collision with a front obstacle is calculated, the possibility of collision is compared with a reference threshold level stored in the storage device. Note that the reason why the driver's line of sight is almost in front is that the face orientation angle θ is the threshold value after the duration of the state in which the face orientation angle θ is within the threshold value θ0 reaches a predetermined time. The duration of the state outside the value θ0 may be until a predetermined time is reached, and when such a determination is made, the calculated collision probability is compared with the reference threshold level.

  From the comparison result, when the possibility of collision reaches the reference threshold level, that is, when the predicted collision time becomes less than or equal to the reference time t1, an alarm is displayed so that an alarm is issued from that time until the collision. A drive command is issued to the display 20 and the alarm buzzer 22. In this case, in order to prompt the driver to avoid or mitigate the collision between the host vehicle and the front obstacle, the alarm display 20 displays an alarm and the alarm buzzer 22 sounds a buzzer (FIG. 2 ( A)).

  Further, as a result of the comparison, the PCS-ECU 12 determines that the driver's line of sight is not facing the front in a situation where the face orientation angle θ is outside the threshold value θ0, and first alerts the driver. When the threshold time tt that should be expected to collide with the obstacle ahead is longer than the reference time t1 (by making it earlier with respect to the time of the collision), the possibility of collision can be increased. The threshold level to be reached is reduced from the reference threshold level. It is determined that the driver's line of sight is not facing the front direction after the duration of the state in which the face angle θ is outside the threshold value θ0 reaches a predetermined time (eg, 0.3 seconds) The duration of the state in which the face angle θ is within the threshold value θ0 may be until the predetermined time is reached.

  In order to reduce the threshold level in this way, the PCS-ECU 12 first has the driver's face orientation angle θ based on the captured image of the camera 18 outside the threshold θ0 for side-by-side discrimination. Thus, when it is determined that the driver's line of sight is not directed in the front direction, the duration for which the state continues thereafter is counted. Then, according to the counted duration of the side look, the threshold level from which the possibility of collision with the front obstacle should be reached in order to start warning to the driver from the above-mentioned reference threshold level is reached. Change the amount of decline. In other words, when the warning to the driver is started, the advance time from the reference time t1 of the threshold time tt that should reach the predicted collision time with the front obstacle is changed.

  Specifically, the PCS-ECU 12 stores in advance in the storage device a map representing the relationship between the look-ahead duration and the threshold time tt as shown in FIG. This map shows that the threshold time tt substantially coincides with the reference time t1 (= the advance time is zero) when the aside look duration is shorter than a predetermined time s1 (for example, 0.5 seconds). When the duration time is equal to or longer than the predetermined time s1, the longer the duration time, the longer the threshold time tt becomes than the reference time t1 (becomes earlier with respect to the time of collision = longer advance time). When the duration is longer than a predetermined time s2 (for example, 1 second) longer than the predetermined time s1, the threshold time tt is longer than the reference time t1 (for example, 3 seconds or 3.5 seconds until the collision). Second) (= maximum advance time). Therefore, the PCS-ECU 12 refers to a map showing the relationship between the aside look duration and the threshold time tt as shown in FIG. The advance time of the threshold time tt is set, and thereafter, every time the look-ahead duration is updated, the threshold level decrease amount corresponding to the look-ahead duration, that is, the advance time of the threshold time tt is set. Set.

  When the PCS-ECU 12 calculates the possibility of collision between the host vehicle and the front obstacle at each time point in a situation where the driver's line of sight is determined not to face the front, the calculated collision is performed. Compare the possibility with the threshold level reduced by an amount corresponding to the look-ahead duration as described above. Specifically, it is determined whether or not the calculated collision predicted time is equal to or less than a threshold time tt that is advanced from the reference time t1 by a time corresponding to the aside continuation time as described above.

  From the comparison result, when the predicted collision time is longer than the threshold time tt longer than the reference time t1 and the possibility of collision does not reach the threshold level after the level drop, the warning display 20 and The drive command for the alarm buzzer 22 is not performed. On the other hand, when the predicted collision time becomes equal to or shorter than the threshold time tt and the possibility of collision reaches the threshold level, the alarm display 20 and the alarm are displayed so that an alarm is issued from that time until the collision. A drive command is issued to the buzzer 22. In this case, in order to prompt the driver to avoid or mitigate the collision between the host vehicle and the front obstacle, the alarm display 20 displays an alarm and the alarm buzzer 22 sounds a buzzer (FIG. 2 ( B)).

  Therefore, in the in-vehicle alarm device 10 of the present embodiment, the driver performs alarm display by the alarm display display 20 for collision avoidance or damage reduction before the collision with the obstacle ahead and warning of the buzzer sound by the alarm buzzer 22. When the line of sight is directed in the front direction, it is performed when the timing at which the driver can take a normal collision avoidance action has elapsed. On the other hand, when the driver removes his / her line of sight from the front direction, it can be performed before the timing at which the driver can take the normal collision avoidance action elapses. That is, before the collision with a front obstacle, when the driver has taken his gaze off from the front direction, the alarm start timing for collision avoidance or damage reduction is It is possible to speed up. Therefore, according to this embodiment, before the collision with the front obstacle, the collision avoidance action is delayed due to the driver's aside while suppressing the driver from being bothered by an alarm as much as possible. It is possible to prevent this, and it is possible to improve safety during vehicle travel.

  Further, in the configuration of the present embodiment, there is a sufficient time until the collision with the front obstacle (specifically, the maximum time of the preceding time from the reference time t1 of the threshold time tt and the preceding time) It is longer than the sum of the minimum time that must be continued for a while to maximize the time), and the driver's line of sight does not face the front. If it continues, the preceding time from the reference time t1 of the threshold time tt is maximized. In this case, the threshold for the predicted collision time to be maximized in a state where the lookout continues. The alarm is started when the value time tt (predetermined time t2) is reached.

  In addition, in the situation where the time until the collision with the front obstacle is not sufficient as described above, when the driver's line of sight does not face the front, the above-mentioned duration depends on the duration of the sideward state. Although the advance time increases, since the collision prediction time becomes equal to or less than the threshold time tt during the increase process, the alarm is started when the collision prediction time becomes equal to or less than the threshold time tt. This means that the advance time from the reference time t1 of the threshold time tt is limited depending on the start timing of the side look with respect to the time of the collision.

  In addition, the driver's look-a-side occurred before the collision with the front obstacle, but before the collision prediction time becomes less than the threshold time tt where the advance time increases with the increase of the look-ahead duration, When the look-ahead is resolved and the driver's line of sight turns to the front, it is preferable to set the threshold time tt to the normal reference time t1 by setting the advance time to zero. This is because if the driver's line of sight turns to the front, the need to advance the alarm start timing earlier than the normal timing is reduced. In this case, as usual, the alarm is started when the predicted collision time becomes the reference time t1 or less.

  Thus, according to the vehicle-mounted alarm device 10 of the present embodiment, the alarm start timing that is advanced when the driver removes the line of sight from the front direction is the duration of the state in which the line of sight is removed and a side look is occurring. It can be changed according to the length. Specifically, the longer the aside look continuation time is, the longer the preceding time from the reference time t1 of the threshold time tt that should reach the predicted time of collision with the front obstacle in starting the warning to the driver. By doing so, the amount of decrease in the threshold level from which the possibility of collision should be reached from the reference threshold level is increased, and the alarm start timing can be advanced.

  For this reason, if the vehicle driver's side look duration is relatively short before the collision with the front obstacle, the alarm start timing will not be much earlier than the point when the possibility of collision reaches the reference threshold level. It is possible to prevent the driver from giving unpleasant feelings due to the warning. In addition, when the vehicle driver's side look duration is relatively long, the warning start timing will be much earlier than the point when the possibility of collision reaches the reference threshold level, so the driver whose line of sight does not turn to the front. It is possible to promptly promote actions for collision avoidance and damage reduction. Therefore, according to the in-vehicle alarm device 10 of the present embodiment, it is possible to perform an appropriate alarm in accordance with the driver's side-by-side state while suppressing annoying the driver by the alarm before the vehicle collision. Yes.

  By the way, in the present embodiment, the in-vehicle alarm device 10 gives an alarm for avoiding or mitigating the collision to the vehicle driver when the possibility of collision with the front obstacle becomes relatively high. The alarm is an alarm display by the alarm display 20 and a buzzer sounding by the alarm buzzer 22. For this reason, especially when the driver is looking aside to remove the line of sight from the front, even if the alarm start timing is advanced, the alarm that stimulates the hearing or vision may not be recognized by the driver. Therefore, there is a risk that the driver will not be warned sufficiently to avoid or reduce the collision before the collision.

  Therefore, in the on-vehicle alarm device 10 of the present embodiment, after the alarm display by the alarm display display 20 and the primary alarm of the buzzer by the alarm buzzer 22 are started at an earlier timing than usual due to the look of the vehicle driver. When the look-aside state continues, a secondary alarm different from the primary alarm is given to the vehicle driver to avoid the above inconvenience. Hereinafter, with reference to FIG. 4 and FIG. 5, the characteristic part of a present Example is demonstrated.

  FIG. 4 shows a flowchart of an example of a control routine executed by the PCS-ECU 12 in the in-vehicle alarm device 10 of the present embodiment. Moreover, FIG. 5 shows the figure for demonstrating the characteristic operation | movement of the vehicle-mounted alarm device 10 of a present Example.

  In this embodiment, the PCS-ECU 12 uses the warning display 20 when the possibility of a collision with a front obstacle reaches a threshold level that is lowered from the reference threshold level due to the driver's side effects. After the primary alarm of the buzzer sounding by the alarm display and the alarm buzzer 22 is started (after the affirmative determination of step 100), (1) The driver's line of sight that has started before the alarm starts continues to look aside And the duration time of the threshold time tt is not less than a predetermined time s3 (for example, 2 seconds) longer than the predetermined time s2 that maximizes the advance time from the reference time t1, and (2) even at the present time It is determined whether or not the looking-aside state continues (step 102).

  As a result, when it is determined that the above conditions (1) and (2) are both satisfied, the predicted collision time between the host vehicle and the front obstacle calculated at the present time is equal to or shorter than the reference time t1. Thus, it is determined whether or not the collision possibility has reached the reference threshold level (step 104). When it is determined that the collision possibility has reached the reference threshold level, the relative speed of the host vehicle with respect to the obstacle ahead is equal to or higher than a predetermined relative speed (for example, +40 km / h), and It is determined whether or not the vehicle speed is equal to or higher than a predetermined speed (for example, 40 km / h) (step 106).

As a result, when an affirmative determination is made in step 106, a drive instruction is given to the brake device 24 so that wheel braking is performed for a predetermined time (for example, 0.5 seconds) from that point (step 108). In this case, the brake device 24 performs wheel braking (alarm braking) as a secondary alarm in order to urge the driver to avoid or mitigate the collision between the host vehicle and the front obstacle by a sensation alarm. The wheel braking as the secondary alarm may be performed at a predetermined deceleration (for example, 2 m / s ² ).

  According to such a process, for example, as shown in FIG. 5A, as a result of the driver's looking aside before the collision with the front obstacle, the warning display is displayed before the possibility of the collision reaches the reference threshold level. Even if the alarm display by 20 and the primary alarm of the buzzer sounding by the alarm buzzer 22 are started, the driver before the collision possibility reaches the reference threshold level (before the predicted collision time becomes less than the reference time t1). When the look of the camera turns to the front and the look-ahead state is resolved, wheel braking as a secondary alarm is not performed regardless of the duration of the look-ahead state until then.

  On the other hand, as shown in FIG. 5B, as a result of the driver's side look before the collision with the front obstacle, the alarm display by the alarm display 20 before the collision possibility reaches the reference threshold level and After the primary alarm of the buzzer sounding by the alarm buzzer 22 is started, when the possibility of collision reaches the reference threshold level, and the duration of the look-ahead state including that time is not less than the predetermined time s3, Immediately at that time, wheel braking is performed as a secondary alarm. Further, as shown in FIG. 5C, as a result of the driver's side look before the collision with the front obstacle, the alarm display by the alarm display 20 and the possibility of the collision before reaching the reference threshold level. After the primary alarm of the buzzer sounding by the alarm buzzer 22 is started, when the possibility of collision reaches the reference threshold level, the duration of the look-ahead state including that time is less than the predetermined time s3. When the side look continuation time is equal to or longer than the predetermined time s3, wheel braking as a secondary alarm is performed for the first time at that time.

  Thus, according to the in-vehicle alarm device 10 of the present embodiment, the alarm display 20 is used before the collision possibility reaches the reference threshold level due to the driver's side-look before the collision with the front obstacle. After the primary alarm of the buzzer sounding by the alarm display and the alarm buzzer 22 is started, the collision prediction time with the obstacle ahead is less than the reference time t1, so that the possibility of collision is above the reference threshold level, and If the sideways continuation time is equal to or longer than the predetermined time s3, a secondary warning for wheel braking using the brake device 24 is further performed. In other words, before a collision with a front obstacle, after a warning display started at an earlier timing than usual due to the driver's side look and the primary warning of the buzzer sounding, the driver's side look continues for a long time When the driver's line of sight turns to the front without doing, a new alarm different from the primary alarm will not be performed, but the primary alarm started at a timing earlier than the normal is performed Nevertheless, when the driver's side aside continues for a predetermined time s3 or more, a secondary warning for wheel braking is performed for a predetermined time on the condition that the possibility of collision has reached the reference threshold level. .

  If such a secondary warning for wheel braking is performed, the driver can know that a sensible alarm accompanied by braking is being issued from the vehicle, in addition to the alarm for stimulating vision and hearing. Therefore, according to the in-vehicle warning device 10 of the present embodiment, in a situation where the vehicle driver keeps looking aside even if a warning that stimulates vision or hearing is performed before the collision with the front obstacle, the vehicle driver In addition, the alarm with a bodily sensation different from the alarm that stimulates the sight and hearing makes it easier to turn the line of sight to the front and further promotes actions for collision avoidance and collision mitigation. Thus, it is possible to execute an appropriate alarm in accordance with the driver's side-by-side condition.

  Further, in this embodiment, the secondary warning for wheel braking indicates that the possibility of a collision has reached the reference threshold level that should be reached when the primary warning is started when the driver is not looking aside. Implemented on condition. In other words, even if the driver's side-view continues for a long time, if the possibility of collision does not reach the reference threshold level, the secondary warning is not made. Therefore, according to the in-vehicle warning device 10 of the present embodiment, the secondary warning of the wheel braking is performed at an unnecessarily early timing after the collision with the front obstacle, after the primary warning display and the primary warning of the buzzer are started. Therefore, it is possible to prevent the driver from being bothered by the secondary alarm.

  In the above-described embodiment, the primary alarm display and the buzzer sounding alarm are described as “first alarm” in the claims, and the secondary alarm for wheel braking is described in the claims as “second alarm”. The reference threshold level corresponds to the “predetermined level” described in the claims, and the PCS-ECU 12 determines that the face orientation angle θ from the camera ECU 16 is the threshold θ0. By comparing, the “gaze direction determining means” described in the claims performs the alarm display by the alarm display display 20 and the primary alarm of the buzzer sounding by the alarm buzzer 22. The "second warning means" described in the claims by executing the processing of step 108 in the routine shown in FIG. Accordingly, when the warning to the driver is started, the amount of decrease in the threshold level from which the possibility of collision with the front obstacle should be reached is changed, that is, to the driver. By changing the advance time from the reference time t1 of the threshold time tt to reach the predicted time of collision with the obstacle ahead of the start of the alarm, the “alarm timing changing means” is described in the claims. "Is realized.

  By the way, in the above-described embodiment, the angle at which the face faces from the front is detected as the vehicle driver's line-of-sight direction. However, the present invention is not limited to this and is directed to the vehicle driver's eyes. The direction itself may be detected.

  Further, in the above-described embodiment, the start timing of the warning that is advanced when the line of sight is removed from the front direction is changed according to the duration of the state where the driver's line of sight is off and a side look is occurring. However, the relationship between the duration of the driver's side look and the threshold time tt that should be predicted for the collision with the front obstacle in starting the warning to the driver is a downwardly convex curve. However, the present invention is not limited to this, and a map in which the relationship between the two is linear or stepped may be used.

  Further, in the above-described embodiment, the start timing of the warning that is advanced when the line of sight is removed from the front direction is changed according to the duration of the state where the driver's line of sight is off and a side look is occurring. However, the present invention is not limited to this. Regardless of the duration of the look-ahead state, when the line of sight is removed from the front direction, it is compared to when it is directed to the front direction. The alarm start timing may be uniformly advanced.

  Further, in the above embodiment, in order to perform the secondary warning of the wheel braking before the collision with the front obstacle, the warning display and the buzzer started at an earlier timing than usual due to the driver's side look. Although it is a requirement that the duration of the driver's side look that continues from before the start of the primary alarm after the primary alarm is given, it is required to reach a predetermined time or more, but the present invention is not limited to this. Further, it may be a requirement that the duration of the sideview reaches a predetermined time or more from the time when the primary alarm is started.

  In the above embodiment, the brake device 24 is used to issue a secondary warning for wheel braking to prompt the driver to perform collision avoidance or collision mitigation. When a device capable of minutely vibrating the steering wheel is mounted on the vehicle, a secondary alarm may be issued to activate the device to prompt the driver to avoid or reduce the collision. The brake device 24 is further used as a device that forcibly brakes the wheels in order to reduce the damage caused by the collision when the possibility of collision with a front obstacle reaches an unavoidable level. It is good as well.

  Further, in the above embodiment, the secondary warning for wheel braking is performed only for a predetermined time (for example, 0.5 second continuously from the start), but the end of the secondary alarm is reduced, for example, due to a collision. For example, the secondary warning may be performed only during the period until the start of the forced wheel braking.

It is a block diagram of the vehicle-mounted alarm device which is one Example of this invention. It is a figure for demonstrating operation | movement of the vehicle-mounted alarm device of a present Example. It is the map showing the relationship between the aside look duration used in a present Example, and threshold time tt. It is a flowchart of an example of the control routine performed in the vehicle-mounted alarm device of a present Example. It is a figure for demonstrating the characteristic operation | movement of the vehicle-mounted alarm device of a present Example.

Explanation of symbols

10 On-vehicle alarm device 12 PCS-ECU
16 Camera ECU
18 Camera 20 Alarm display 22 Alarm buzzer 24 Brake device

Claims (5)

Collision with a front obstacle is possible when the gaze direction discriminating unit discriminates whether or not the gaze direction of the vehicle driver is in the front direction, and when the gaze direction discriminating unit determines that the gaze direction is in the front direction On the other hand, when it is determined that the line-of-sight direction is not in the front direction, the first possibility is given to the vehicle driver before the possibility of collision with a front obstacle reaches the predetermined level. An on-vehicle alarm device comprising:
After the first warning is started before the first warning means reaches the predetermined level, the time when the possibility of collision with the front obstacle reaches the predetermined level. in the case the duration determination result as the viewing direction is in a state not in the front direction of the sight line direction determining means is a predetermined time or more, a second alarm that is different from the first alarm to the vehicle driver There line toward, whereas, the continuation when the time is less than the predetermined time, the second intends row toward the second alarm to the vehicle driver when the said duration is equal to or more than the predetermined time An on-vehicle alarm device comprising the alarm means. As a result of determination by the line-of-sight direction determination unit, the first warning unit causes a first collision before reaching the predetermined level according to the duration of the state where the line-of-sight direction is not in the front direction. vehicle alarm system according to claim 1 Symbol mounting, characterized in that it comprises a timing changing means for changing the timing for starting the alarm. The on-vehicle alarm device according to claim 1 or 2 , wherein the possibility of a collision with a front obstacle corresponds to a time until the host vehicle collides with a front obstacle. The first alarm is a buzzer sound or an alarm display;
The in-vehicle alarm device according to any one of claims 1 to 3 , wherein the second alarm is an alarm brake for decelerating the vehicle. The on-vehicle alarm device according to claim 4, wherein the second alarm means continues the alarm braking for a predetermined period after the alarm braking is started.

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