JP2009154590A - Collision damage reducing device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to avoid a situation that a driver is confused and vehicle behavior becomes unstable. <P>SOLUTION: This collision damage reducing device comprises a detection period calculating means 16 calculating a period of continuously detecting an obstacle having the possibility of colliding with the vehicle as a detection continuous period ΣT<SB>D</SB>, a monitoring object recognizing means 17 determining whether or not to treat the obstacle as a monitoring object in response to the detection continuous period ΣT<SB>D</SB>and to treat the obstacle as an operation object of accessories 12 and 13, a reliability index setting means 18 setting a reliability index R by determining that there is the possibility of colliding with the obstacle when the detection continuous period ΣT<SB>D</SB>becomes larger than a predetermined detection period threshold value T<SB>Dth1'</SB>, T<SB>Dth2'</SB>and T<SB>Dth3</SB>, and an attentiveness index setting means 32 setting an attentiveness index AL of reducing as the attentiveness of the driver is decreased, and a detection period threshold value correction means 33 increasingly correcting the detection period threshold value T<SB>Dth1'</SB>, T<SB>Dth2'</SB>and T<SB>Dth3</SB>as the attention power index AL reduces. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a collision damage reducing device such as an alarm device or an automatic braking device used in a vehicle.

2. Description of the Related Art Conventionally, a device that performs braking of a vehicle before a traveling vehicle collides with an obstacle in front of the host vehicle (for example, a preceding vehicle that is traveling, a preceding vehicle that is stopped, a power pole, etc.) Collision damage reduction brake device) has been developed.
In addition, a device (so-called collision warning device) has been developed that alerts the driver by sounding an alarm or winding up a seat belt before colliding with an obstacle.

A series of devices such as the collision damage reducing brake device and the collision warning device are collectively referred to as “collision damage reducing device” herein.
The following patent document 1 and patent document 2 exist as specific examples disclosing the technology related to the collision damage reducing apparatus.
Patent Document 1 discloses a technique for avoiding a malfunction by delaying the operation timing of the brake means (14), the alarm device (13), etc. during a predetermined operation.

Patent Document 2 predicts the course of the host vehicle, and determines the possibility of contact with an obstacle based on the positional relationship between the predicted course and the obstacle, thereby erroneously detecting the possibility of contact with the obstacle. A technique for preventing such a problem is disclosed.
JP 2007-137126 A JP 2004-38245 A

Both the technique of Patent Document 1 and the technique of Patent Document 2 share the same problem of avoiding alarms and brake operation that are unnecessary for the driver.
However, in some cases, the technique of Patent Document 1 and the technical idea of Patent Document 2 cannot solve the problem. For example, if the vehicle is traveling on a straight road, the road is curved in front of the straight road, and a pole stands at the end of the curved road, the operation delay of the device due to the driving operation It is difficult to exclude the pole from the target of warning or automatic braking by the method of determining the possibility of contact based on the predicted course.

In addition, if the collision damage mitigation device operates in a situation that is not necessary for the driver, the behavior of the vehicle may become unstable, causing the driver to feel unnecessary annoyance or confusing the driver. May lead to a situation.
The present invention has been devised in view of such a problem, and even in various roads and driving situations, it is possible to avoid the situation where the behavior of the vehicle becomes unstable due to the confusion of the driver, and the vehicle is damaged. An object is to provide a mitigation device.

  In order to achieve the above object, the collision damage mitigation device for a vehicle according to the present invention (Claim 1) monitors an obstacle existing on the vehicle traveling direction side and has a possibility of colliding with the monitored obstacle. A collision damage mitigation device for a vehicle that activates the equipment provided to the vehicle in response, and is an object that is mounted on the vehicle and exists on the traveling direction side of the vehicle, and may collide with the vehicle An obstacle detection means for detecting the obstacle as an obstacle, a detection period calculation means for calculating a period during which the object is continuously detected as the obstacle by the obstacle detection means, and a detection period calculation Monitoring object recognition means for determining whether the obstacle is to be monitored by the collision damage mitigation device and whether to operate the equipment according to the detection duration calculated by the means, and the detection continuation Period is a predetermined detection period A reliability index setting means for determining that there is a possibility of collision with the obstacle when the value exceeds the value and setting a reliability index, and an attention index that decreases as the driver's attention decreases It is characterized by comprising attention index setting means and detection period threshold correction means for correcting the detection period threshold to increase as the attention index set by the attention index setting means decreases.

  According to a second aspect of the present invention, there is provided the vehicle collision damage reducing apparatus according to the first aspect of the present invention, wherein the driver specifies a relationship in which the reaction time of the driver increases as the attention index decreases. It comprises a time map and reaction time estimation means for estimating the reaction time by applying the attention index set by the attention index setting means to the reaction time map.

  According to a third aspect of the present invention, there is provided a collision damage reducing device for a vehicle according to the present invention, wherein the collision time estimating means for estimating a collision prediction time until the vehicle collides with the obstacle, When the predicted collision time estimated by the collision time estimation means falls below a predetermined collision threshold, the operation control means for operating the equipment, and as the reaction time estimated by the reaction time estimation means becomes longer, A collision threshold correction means for increasing and correcting the collision threshold is provided.

  According to a fourth aspect of the present invention, there is provided the vehicle collision damage reducing device according to any one of the first to third aspects, wherein the equipment has a warning device for issuing a warning to the driver. And an automatic braking device that brakes the vehicle regardless of the driver's intention. The detection period threshold value includes a first detection period threshold value and a second detection period threshold value that is greater than the first detection period threshold value. Is set, and when the detection duration of the obstacle exceeds the second detection period threshold, the monitoring object certifying means detects the obstacle as an operation target of the alarm device and the automatic braking device. And when the obstacle detection duration is less than the first detection period threshold, the obstacle is not set as an operation target of the alarm device and the automatic braking device, and the obstacle is detected. The duration is not less than the first detection period threshold and not more than the second detection period threshold. If that is characterized not the operation subject to the obstacle and the operating target of said alarm device and the automatic brake device.

According to the vehicle collision damage reducing apparatus of the present invention, it is possible to avoid a situation in which the vehicle behavior becomes unstable even in various roads and driving situations. (Claim 1)
In addition, the reaction time can be quickly and accurately estimated by using a reaction time map that defines that the driver's reaction time increases as the attention index decreases. (Claim 2)
As the driver's reaction time becomes longer, the equipment can be operated at an earlier timing than usual. (Claim 3)
Also, by controlling whether or not the alarm device and the automatic braking device as the equipment are to be operated according to the obstacle detection continuation period, the operation of these alarm devices and automatic braking device is required. It can be operated properly. (Claim 4)

  Hereinafter, a vehicle collision damage reducing device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram mainly showing the overall configuration, and FIG. 3 is a schematic diagram showing a TTC map before correction, FIG. 4 is a schematic diagram showing a TTC map after correction, FIG. 5 is a schematic diagram showing a reaction time map, FIG. 6 and FIG. FIG. 8, FIG. 9, FIG. 10 and FIG. 11 are schematic flowcharts showing subroutines in the operation of this apparatus, and FIG. 12 is a diagram showing a vehicle on which the apparatus is mounted. FIG. 13 is a schematic graph showing accreditation accuracy for accreditation of a monitoring object in this apparatus.

As shown in FIG. 1, the vehicle 10 is mainly provided with a millimeter wave radar unit (obstacle detection means) 11, a buzzer 12, a brake ECU 13, and a damage reduction system ECU 14.
The millimeter wave radar unit 11 is provided near the front end of the vehicle 10 and emits millimeter wave radio waves and receives radio waves reflected from an object existing in front of the vehicle 10 to detect the object as an obstacle. To do. The millimeter wave radar unit 11 is connected to a damage reduction system ECU 14 (to be described later) via a CAN (Controller Area Network) standard communication cable (not shown).

The millimeter wave radar unit 11 can simultaneously detect a plurality of obstacles.
The millimeter wave radar unit 11 has a built-in radar ECU (not shown). The radar ECU can calculate a relative distance L _R between the obstacle and the vehicle 11 and a relative speed V _R between the obstacle and the vehicle 10 based on the received radio wave, and can output them to the damage reduction system ECU 14. It is like that. Further, the radar ECU determines whether the detected obstacle is moving, whether it is a stationary object, whether it is moving, but whether it is moving still, and determines the result of the damage reduction system ECU 14. Can be output.

The buzzer 12 is an alarm device provided in a vehicle interior (not shown), and is urged to alert the driver of the vehicle 10. The buzzer 12 is connected to the damage reduction system ECU 14 by a harness, and the damage reduction system ECU 14 is operated by supplying power to the buzzer 12.
The brake ECU (automatic braking device; equipment) 13 is an electronic control unit that controls a brake device (not shown) provided on each wheel 15 of the vehicle 10. The brake ECU 13 is connected to the damage reduction system ECU 14 by a CAN standard communication cable, and is operated under the control of the damage reduction system ECU 14.

The vehicle 10 is also provided with a steering angle sensor (not shown) for detecting a turning angle (ie, steering angle) θSW of a steering wheel (not shown) operated by the driver. The detection result by the steering angle sensor is read by the damage reduction system ECU 14.
The damage reduction system ECU 14 is an electronic control unit provided with a CPU, a memory, an interface unit, etc., not shown. The damage reduction system ECU 14 includes a detection period calculation unit (detection period calculation unit) 16, a monitoring target recognition unit (monitoring target determination unit) 17, and a reliability setting unit (reliability determination), all realized as software. Means) 18 and an operation control unit (collision time estimation means, operation control means) 19 are provided.

Further, the damage reduction system ECU 14 includes a reaction time estimation unit (reaction time estimation unit) 31, an attention level setting unit (attention level index setting unit) 32, and a detection period threshold correction unit (all implemented as software). A detection period threshold correction unit) 33 and a collision threshold correction unit (collision threshold correction unit) 34 are provided.
In addition, a reaction time map 35 and a TTC map 36 are stored in the memory in the damage reduction system ECU 14.

Of these, detection period calculating section 16 is for calculating the period during which the obstacle is continuously detected by the millimeter wave radar unit 11 as a detection duration oT _D.
Reliability determining unit 18 is configured to set the reliability coefficient R to be monitored in accordance with the detected duration oT _D calculated by the detection period calculating unit 16.
That is, as shown in FIG. 2, the detection duration oT _D is less than or equal to the first detection period threshold second detecting period threshold but exceeds (detecting period threshold) T _Dth1 (detecting period threshold) T _Dth2, i.e., When T _Dth1 <ΣT _D ≦ T _Dth2 , the reliability setting unit 18 considers that the reliability of the monitoring target is “relatively low” and sets the reliability coefficient R to 1.

Further, the reliability setting unit 18 has a detection continuation period ΣT _D that exceeds the second detection period threshold value T _Dth2 , but is _{equal to} or less than the third detection period threshold value (detection period threshold value) T _Dth3 (that is, T _Dth2 <ΣT _D ≦ T _Dth3 ), the reliability of the monitoring target is regarded as “relatively high”, and the reliability coefficient R is set to 2.
Furthermore, when the detection continuation period ΣT _D exceeds the third detection period threshold value T _Dth3 (that is, T _Dth3 <ΣT _D ), the reliability setting unit 18 _determines that the reliability of the monitoring target is “very high”. The reliability coefficient R is set to 3.

The first detection period threshold value T _Dth1 , the second detection period threshold value T _Dth2, and the third detection period threshold value T _Dth3 are corrected by a detection period threshold value correction unit 33 described later. The first detection period threshold value T _Dth1 is set as 1 second and the second detection period threshold value T _Dth2 is set as 1.5 seconds as a reference value when the driver's attention is not reduced (that is, in normal time) The third detection period threshold value T _Dth3 is set as 2 seconds.

The monitoring object recognition unit 17 detects an obstacle detected by the millimeter wave radar unit 11 in accordance with the reliability coefficient R set by the reliability setting unit 18, and an operation control unit (collision damage reduction device) 19 described later. In addition to being a monitoring target, it is determined whether the buzzer (equipment) 12 and the brake ECU (equipment) 13 should be actuated.
More specifically, when the reliability coefficient R set by the reliability setting unit 18 is 0 or less (R ≦ 0), the monitoring target recognition unit 17 sets the obstacle as an operation target of the buzzer 12. It is not recognized and is not recognized as an operation target of the brake ECU 13.

In addition, when the reliability coefficient R exceeds 0 and is 1 or less (0 <R ≦ 1), the monitoring target recognition unit 17 recognizes the obstacle as an operation target of the buzzer 12, but the brake ECU 13 It is not recognized as an operation target.
In addition, when the reliability coefficient R exceeds 1 and is 2 or less (1 <R ≦ 2), the monitoring target recognition unit 17 recognizes the obstacle as an operation target of the buzzer 12 and the brake ECU 13. It is also recognized as the target of the warning action.

Further, when the reliability coefficient R exceeds 2 (R> 2), the monitoring target recognition unit 17 recognizes the obstacle as an operation target of the buzzer 12 and as an operation target of the braking operation by the brake ECU 13. Also come to recognize.
In other words, by making the operation that has a strong influence on the driving of the vehicle 10 require higher reliability, an erroneous detection of an obstacle, warning operation by the buzzer 12, warning braking and emergency braking by the brake ECU 13 can be performed. It has become possible to prevent accidents from occurring more effectively.

Here, warning braking is braking that causes the vehicle 10 to generate a deceleration of about 0.3 G (acceleration of about -0.3 G), and emergency braking is a deceleration of about 0.6 G. This is braking that causes the vehicle 10 to generate (acceleration of about −0.6 G).
Based on the time until the vehicle 10 collides with an obstacle (collision prediction time TTC: Time To Collision) and the reliability coefficient R set by the reliability setting unit 18, the operation control unit 19 Urgency for executing measures to avoid colliding with objects (collision avoidance urgency), or urgency for executing measures for reducing damage caused by collision of vehicle 10 with an obstacle (damage mitigation urgency) Is supposed to be estimated. The urgency of response including these collision avoidance urgency and damage mitigation urgency is referred to as “response urgency”.

And this operation control part 19 performs control which calls a driver | operator's attention or operates a brake device according to this correspondence urgent level, ie, damage reduction control.
More specifically, the operation control unit 19 estimates the collision prediction time TTC based on the detection result by the millimeter wave radar unit 11 based on the relative distance L _R and the relative speed V _R between the obstacle and the vehicle 10. In addition, it is estimated that the shorter the collision prediction time TTC is, the higher the response urgency is.

That is, the operation control unit 19 belongs to which of the first collision determination area A1, the second collision determination area A2, and the third collision determination area A3 defined by the TTC map 36 shown in FIG. The damage reduction control is executed according to the determination result.
In the TTC map 36, the collision prediction time TTC is defined on the vertical axis, and the relative speed VR is defined on the horizontal axis. Further, the TTC map 36 defines a first collision threshold line (collision threshold value) C _th1 , a second collision threshold line (collision threshold value) C _th2, and a third collision threshold line (collision threshold value) C _th3 .

Further, the TTC map 36 includes a first collision determination area A1 that is an area between the first collision threshold line C _th1 and the second collision threshold line C _th2 , a second collision threshold line C _th2, and a third collision threshold line. A second collision determination area A2 which is an area between the line C _th3 and a third collision determination area A3 which is an area below the third collision threshold line C _th3 are defined.
As shown in FIG. 4, the first collision threshold line C _th1 , the second collision threshold line C _th2, and the third collision threshold line C _th3 in the TTC map 36 are corrected by a collision threshold correction unit 34 described later. There is a case.

However, even if the response urgency is set according to the predicted collision time TTC, the operation control unit 19 changes the content of the damage reduction control according to the reliability coefficient R set by the reliability setting unit 18. It is like that. This point will be explained in a little more detail.
When the reliability coefficient R is set to 0 by the reliability setting unit 18, the operation control unit 19 does not execute damage reduction control regardless of the size of the collision prediction time TTC. That is, regardless of whether the state of the vehicle 10 belongs to any of the first collision determination area A1, the second collision determination area A2, and the third collision determination area A3 defined in the TTC map 36, the operation control unit 19 The buzzer 12 is not sounded, and neither warning braking nor emergency braking by the brake ECU 13 is performed.

  When the reliability coefficient R is set to 1 by the reliability setting unit 18, the operation control unit 19 controls only on / off of the alarm buzzer 12 according to the magnitude of the predicted collision time TTC. That is, only when the state of the vehicle 10 belongs to the first collision determination area A1, the second collision determination area A2 or the third collision determination area A3 defined in the TTC map 36, the operation controller 19 is 12 is sounded, but warning braking and emergency braking by the brake ECU 13 are not executed.

  Further, when the reliability coefficient R is set to 2 by the reliability setting unit 18, the operation control unit 19 sounds the buzzer 12 when the state of the vehicle 10 belongs to the first collision determination area A1 of the TTC map 36. However, the brake ECU 13 does not execute warning braking and emergency braking. When the reliability coefficient R is set to 2 and the state of the vehicle 10 belongs to the second collision determination area A2 or the third collision determination area A3 of the TTC map 36, the operation control unit 19 sets the buzzer 12 to the buzzer 12. In addition to sounding, warning braking by the brake ECU 13 is executed, but emergency braking is not executed.

  Further, when the reliability coefficient R is set to 3 by the reliability setting unit 18, the operation control unit 19 sets the buzzer 12 when the state of the vehicle 10 belongs to the first collision determination area A1 of the TTC map 36. Although it sounds, warning braking and emergency braking by the brake ECU 13 are not executed. When the reliability coefficient R is set to 3 and the state of the vehicle 10 belongs to the second collision determination area A2 of the TTC map 36, the operation control unit 19 sounds the buzzer 12 and the brake ECU 13 Warning braking is executed, but emergency braking is not executed. Further, when the reliability coefficient R is set to 3 and the state of the vehicle 10 belongs to the third collision determination area A3 of the TTC map 36, the operation control unit 19 sounds the buzzer 12 and the brake ECU 13 Warning braking and emergency braking are executed.

The reaction time estimation unit 31 estimates the reaction time TR of the driver of the vehicle 10 by applying the attention level AL set by the attention level setting unit 32 described later to the reaction time map 35. The attention level AL is an index indicating the degree of driver's attention.
As shown in FIG. 5, the reaction time map 35 is a map that defines the relationship between the attention level AL and the reaction time TR. More specifically, the reaction time map 35 defines a relationship in which the reaction time TR becomes longer as the attention level AL becomes smaller. Note that the attention level AL means that the driver's attention is reduced as the value decreases. Therefore, the reaction time map 35 defines a relationship in which the driver's reaction time TR becomes longer as the driver's attention is reduced.

The attention level setting unit 32 sets the above attention level (driver's alertness) AL based on an output image from a white line camera (not shown), a steering angle θ _SW detected by a steering angle sensor, and the like. It is. In the present embodiment, the meandering amount of the vehicle 10 is simply obtained from the steering angle θ _{SW and the} like within a predetermined period, and the attention level AL is set to the minimum value (AL = 1) and the maximum value according to the meandering amount. (AL = 5) is set stepwise. Since various methods for calculating the attention level AL are disclosed, detailed description is omitted here.

As the attention level AL set by the attention level setting unit 32 becomes smaller, the detection period threshold correction unit 33, as indicated by the arrows in FIG. 2, the first detection period threshold T _Dth1 and the second detection period. The threshold value T _Dth2 and the third detection period threshold value T _Dth3 are increased and corrected.
The collision threshold correction unit 34 has a longer reaction time TR estimated by the reaction time estimation unit 31 than the first collision threshold line C _th1 , the second collision threshold line C _th2, and the third collision threshold line C _th3 shown in FIG. Accordingly, an increase correction is made as indicated by an arrow in FIG.

Since the vehicle collision damage reducing apparatus according to the embodiment of the present invention is configured as described above, the following operations and effects are achieved. In addition, here, it mainly demonstrates along the flowchart shown in FIGS. 6-11, and is explained in full detail using FIG. 1 and FIG. 12 which show an example of the specific driving | running | working condition of the vehicle 10. FIG.
The millimeter wave radar unit 11 mounted on the traveling vehicle 10 operates to detect an obstacle (step S11 in FIG. 6).

Here, as shown in FIGS. 1 and 12, the preceding vehicle 21 traveling in front of the vehicle 10 and the utility pole 22 and the pole 23 provided on the road side are detected as obstacles by the millimeter wave radar unit 11. Shall.
Thereafter, the preceding vehicle 21 continuously detected period as an obstacle by utility poles 22 and 23 millimeter wave radar unit 11, i.e., the detection duration oT _D, the detection period calculation unit 16 calculates, respectively. (Step S12)
Then, the attention level setting unit 32 sets the attention level AL of the driver of the vehicle 10 based on the meandering amount obtained from the steering angle θ _SW detected by the steering angle sensor (step S13).

  Further, the reaction time estimation unit 31 applies the attention level AL set in step S13 to the reaction time map 35 shown in FIG. 5 to estimate the reaction time TR of the driver of the vehicle 10 (step S14). Therefore, when it is considered that the attention level AL is relatively low and the driver's attention is reduced, the reaction time TR is estimated to be relatively long, while the attention level AL is relatively high. When it is considered that the attention of the person is not reduced, the reaction time TR is estimated to be relatively short.

Then, as the attention level AL set in step S13 becomes smaller, the detection period threshold correction unit 33, as shown in FIG. 2, the first detection period threshold T _Dth1 , the second detection period threshold T _Dth2, and The third detection period threshold value _TDth3 is corrected so as to increase (step S15).
Further, as the reaction time TR set in step S14 becomes longer, the collision threshold correction unit 34 has the first collision threshold line C _th1 , the second collision threshold line C _th2 and the third collision threshold _line shown in FIG. C _th3 is increased and corrected as shown in FIG. 4 (step S16).

Then, the monitoring object recognition unit 17 determines whether or not the detection continuation period ΣT _D calculated by the detection period calculation unit 16 in step S12 exceeds the first detection period threshold value T _Dth1 (= 1 second) ( Step S17 in FIG. At this time, if the detection continuation period ΣT _D does not exceed the first detection period threshold value T _Dth1 (No route of Step S17), the monitoring target recognition unit 17 should not make the obstacle to be monitored (Step S18). ) And the reliability setting unit 18 sets the reliability coefficient R to 0 (step S19).

After that, as a subroutine, damage reduction control when the reliability coefficient R is 0 is executed (step S20). However, in this case, as shown in FIG. 8, the operation control unit 19 does not execute the damage reduction control regardless of the size of the predicted collision time TTC. More specifically, as shown in FIG. 8, whether or not the predicted collision time TTC exceeds the first collision threshold line C _th1 defined in the TTC map 36 (step S41), or the predicted collision time TTC is first collision threshold line C _th1 whether exceeds the in and and 1 collision threshold line C _th1 or less (step S42), or time-to-collision TTC is at a second collision threshold line C _th2 or less and the third collision threshold If the reliability coefficient R is 0 regardless of whether or not it exceeds the line C _th3 (step S43), the operation control unit 19 does not sound the buzzer 12, and warning braking by the brake ECU 13 is also emergency braking. Is not executed (step S44).

On the other hand, when the detection continuation period ΣT _D exceeds the first detection period threshold value T _Dth1 (Yes route in step S17 in FIG. 7), the monitoring target _{authentication} unit 17 determines that the obstacle should be the monitoring target. Then, the operation control unit 19 sets the obstacle as a monitoring target (step S21).
Then, the reliability setting unit 18 determines whether or not the detection continuation period ΣT _D exceeds the second detection period threshold value T _Dth2 (= 1.5 seconds) (step S22). Here, when it is determined that the detection continuation period ΣT _D is _{equal to} or less than the second detection period threshold value T _Dth2 (No route in Step S22), the reliability setting unit 18 considers that the reliability of the monitoring target is relatively low. The reliability coefficient R is set to 1 (step S23).

After that, as a subroutine, damage reduction control when the reliability coefficient R is 1 is executed (step S24). In this case, as shown in FIG. 9, the operation control unit 19 controls only on / off of the alarm buzzer 12 according to the magnitude of the predicted collision time TTC.
More specifically, when the collision prediction time TTC exceeds the first collision threshold line C _th1 defined in the TTC map 36 (Yes route in step S51), the operation control unit 19 sounds the buzzer 12. In addition, neither the warning braking nor the emergency braking by the brake ECU 13 is executed (step S54).

On the other hand, when the collision prediction time TTC is equal to or _shorter than the first collision threshold line C _th1 (Yes route in step S52), the collision prediction time TTC is equal to or shorter than the second collision threshold line C _th2 and the third Regardless of whether or not the collision threshold line C _th3 is exceeded (step S53), the operation control unit 19 sounds the buzzer 12, but does not execute warning braking and emergency braking by the brake ECU 13 (step S55).

On the other hand, when it is determined that the detection continuation period ΣT _D exceeds the second detection period threshold _TDth2 (Yes route in step S22 in FIG. 7), the reliability setting unit 18 determines that the detection continuation period ΣT _D is third. It is determined whether or not the detection period threshold value T _Dth3 (= 2 seconds) is exceeded (step S25).
Here, when it is determined that the detection continuation period ΣT _D is equal to or _shorter than the third period T _Dth2 (No route in step S25), the reliability setting unit 18 determines the reliability of the monitoring target certified by the monitoring target certification unit 17. The reliability is assumed to be relatively high, and the reliability coefficient R is set to 2 (step S26).

Thereafter, damage reduction control is executed as a subroutine when the reliability coefficient R is 2 (step S27). More specifically, as shown in FIG. 10, when the predicted collision time TTC exceeds the first collision threshold line C _th1 (Yes route in step S61), the operation control unit 19 does not sound the buzzer 12. Moreover, neither warning braking nor emergency braking by the brake ECU 13 is executed (step S64).

Further, when the collision prediction time TTC is equal to or _shorter than the first collision threshold line C _th1 and exceeds the second collision threshold line C _th2 (Yes route of Step S62), the operation control unit 19 sounds the buzzer 12. However, warning braking and emergency braking by the brake ECU 13 are not executed (step S65).
Further, when the predicted collision time TTC becomes equal to or shorter than the second collision threshold line C _th2 , regardless of whether or not the predicted collision time TTC exceeds the third collision threshold line C _th3 (Yes route and No route in step S63). The operation control unit 19 sounds the buzzer 12 and executes warning braking by the brake ECU 13, but does not execute emergency braking (step S66).

On the other hand, when it is determined that the detection continuation period ΣT _D exceeds the third period T _Dth2 (Yes route in step S25), the reliability setting unit 18 determines the reliability of the monitoring target certified by the monitoring target certification unit 17. The degree of reliability is regarded as extremely high, and the reliability coefficient R is set to 3 (step S28).
After that, as a subroutine, damage reduction control when the reliability coefficient R is 3 is executed (step S29). More specifically, as shown in FIG. 11, when the collision prediction time TTC exceeds the first collision threshold line C _th1 (Yes route in step S71), the operation control unit 19 does not sound the alarm buzzer. Moreover, neither warning braking nor emergency braking by the brake ECU 13 is executed (step S74).

In addition, when the collision prediction time TTC is equal to or _shorter than the first collision threshold line C _th1 and exceeds the second collision threshold line C _th2 (Yes route in Step S72), the operation control unit 19 sounds the buzzer 12. However, warning braking and emergency braking by the brake ECU 13 are not executed (step S75).
When the collision prediction time TTC is equal to or shorter than the second collision threshold line C _th2 and exceeds the third collision threshold line C _th3 (Yes route in step S73), the operation control unit 19 rings the buzzer 12 At the same time, warning braking by the brake ECU 13 is executed, but emergency braking is not executed (step S76).

When the predicted collision time TTC becomes equal to or shorter than the third collision threshold line C _th3 (Yes route in step S74), the operation control unit 19 sounds the buzzer 12 and executes warning braking by the brake ECU 13, and Then, emergency braking is executed (step S77).
Hereinafter, the case shown in FIG. 1 and FIG.

It is assumed that the traveling vehicle 10 has run through the utility pole 22 and the pole 23.
At this time, it is assumed that the period during which the millimeter wave radar unit 11 continuously detects the utility pole 22 and the pole 23 as an obstacle (detection continuation period ΣT _D ) is an extremely short period (for example, 0.7 seconds) (step S11). And S12).
At this time, it is assumed that the attention level AL is changed from 5 to 3 by the attention level setting unit 32 as the driver's attention decreases (step S13).

In this case, the reaction time estimation unit 31 estimates that the reaction time TR when the attention level AL is 3 is 1.13 seconds (see FIG. 5; step S14).
Then, the detection period threshold correction unit 33 causes the reaction time TR when the attention level AL is 5 (that is, the reference reaction time TR0 = 1.0 second) and the reaction time TR when the attention level AL is 3. (That is, the reaction time change amount TRdef = 0.13 seconds) is changed to the first detection period threshold value T _Dth1 , the second detection period threshold value T _Dth2, and the third detection period threshold value T _Dth3. Corrections to increase each are performed. That is, in this case, the first detection period threshold value T _Dth1 is corrected from 1 second to 1.13 seconds (see FIG. 2; step S15).

That is, in this case, the detection durations ΣT _D (= 0.7 seconds) of the utility poles 22 and poles 23 are equal to or shorter than the corrected first detection period threshold value T _Dth1 (= 1.13 seconds). The utility pole 22 and the pole 23 are not monitored by the operation control unit 19 (No route in step S17 and step S18). Each detection continuation period ΣT _D (= 0.7 seconds) of the utility pole 22 and the pole 23 is also equal to or less than the first detection period threshold value T _Dth1 (= 1 second) before correction. Therefore, even when the attention level AL decreases from 5 to 3, or even when the attention level AL remains at 5, the buzzer 12 does not ring due to the power pole 22 and the pole 23. Further, neither warning braking nor emergency braking is performed (step S44).

On the other hand, it is assumed that the millimeter wave radar unit 11 continuously detects the preceding vehicle 21 as an obstacle for a relatively long period (for example, 2.05 seconds) (steps S11 and S12).
At this time, as in the case where the utility pole 22 and the pole 23 are detected, the attention level AL is changed from 5 to 3 (step S13), and the reaction time TR is estimated to be 1.13 seconds. (Step S14).

Then, the detection period threshold value correction unit 33 increases the reaction time variation TRdef (= 0.13 seconds) from the first detection period threshold value T _Dth1 , the second detection period threshold value T _Dth2, and the third detection period threshold value T _Dth3 . Correction is performed. That is, in this case, the second detection period threshold value T _Dth2 is corrected from 1.5 seconds to 1.63 seconds (step S15).
Further, in this case, the collision threshold correction unit 34 causes the maximum value of the first collision threshold line C _th1 (that is, 2.4 seconds), the maximum value of the second collision threshold line C _th2 (that is, 1.6 seconds), and the first value. As shown in FIG. 4, the maximum value of the three collision threshold line C _th3 (that is, 0.8 seconds) is increased and corrected by the reaction time change amount TRdef (= 0.13 seconds), respectively. That is, in this case, the maximum value of the first collision threshold line C _th1 is corrected from 2.4 seconds to 2.53 seconds, and the maximum value of the second collision threshold line C _th2 is changed from 1.6 seconds to 1.73. The maximum value of the third collision threshold line C _th3 is corrected from 0.8 seconds to 0.93 seconds (step S16).

And the detection continuation period ΣT _D of the preceding vehicle 21 is 2.05 seconds, which is larger than the corrected first detection period threshold value T _Dth1 (= 1.13 seconds) (Yes route of step S17), Furthermore, although it is larger than the corrected second detection period threshold value T _Dth2 (= 1.63 seconds) (Yes route in step S22), it is below the corrected third detection period threshold value T _Dth3 (= 2.13 seconds). Yes (No route in step S25).

Therefore, the reliability setting unit 18 considers that the reliability of the preceding vehicle 21 as an obstacle is relatively high, and sets the reliability coefficient R to 2 (step S26).
However, if there was no correction of the second detection period threshold value T _Dth2 by the detection period threshold value correction unit 33, the reliability coefficient R as an obstacle of the preceding vehicle 21 should be 3. That is, the third detection period threshold value T _Dth3 before correction is 2 seconds. The detection continuation period ΣT _D (= 2.05 seconds) of the preceding vehicle 21 is not less than the third detection period threshold value T _Dth3 (= 2 seconds) before this correction (Yes route of step S22). The reliability setting unit 18 should have set the reliability coefficient R as an obstacle of the preceding vehicle 21 to 3 (step S29).

However, since the first detection period threshold value T _Dth1 , the second detection period threshold value T _Dth2 and the third detection period threshold value T _Dth3 are corrected according to the decrease in the driver's attention, it is inherently an obstacle. Even if the obstacle is included in the monitoring target because its reliability R is relatively high, it may be excluded from the monitoring target.
In other words, for drivers with reduced alertness, the damage mitigation control is focused on obstacles with higher reliability than usual so that the situation where the driver is confused is avoided and the behavior of the vehicle is unstable. Can be avoided.

That is, it is considered that a driver who has a low level of attention has a lower ability to judge than usual. And it is preferable that as little information as possible is given to the driver whose judgment power is reduced. However, information essential for driving the vehicle 10 needs to be given to the driver.
Therefore, in the present invention according to the present embodiment, as the driver's attention is reduced, the obstacle reliability R is set low so that the obstacle to be alarmed is carefully selected and It is intended to satisfy both contradictory requirements of suppressing the amount of information and extracting necessary information for the driver at a high level.

Further, the first detection period threshold value T _Dth1 , the second detection period threshold value T _Dth2 and the third detection period threshold value T _Dth3 are corrected according to the degree of decrease in the driver's attention, and the obstacle reliability R is _inevitably increased. Does not increase. In other words, since the damage reduction control is not executed only in accordance with the collision prediction time TTC, unnecessary warning sound, warning braking and emergency braking are not executed, which causes the driver's mental stress to be reduced. It can also prevent an increase.

Furthermore, since the first and second collision threshold lines C _th1 , C _th2 and C _th3 are corrected by the collision threshold correction unit 34, damage is reduced at a timing earlier than normal. Control can be executed. That is, the warning sound, warning braking, or emergency braking can be executed at an earlier timing when the response time TR increases (reaction time change amount TRdef) due to the reduction of the driver's attention.

Thereby, a driver | operator's attention is alerted and the possibility that the situation where the vehicle 10 collides with the preceding vehicle 21 can be increased. Further, even if a situation occurs in which the vehicle 10 collides with the preceding vehicle 21, the damage can be reduced as much as possible.
Here, the technique of the above-mentioned patent document 1 and the technique of patent document 2 which are conventional techniques will be compared with the present invention according to the present embodiment.

In the technology of Patent Document 1 and the technology of Patent Document 2, although the possibility of whether the host vehicle collides with an obstacle is estimated or the operation timing of the brake device or the alarm device is changed, The obstacle detected by the millimeter wave radar or the laser radar is not selected as an obstacle to be monitored by the collision damage reducing apparatus.
In such a conventional technique, since the collision probability is calculated for all the various obstacles detected by the laser radar and the millimeter wave radar, the processing load of the collision damage reducing apparatus increases.

  In contrast, in the present invention according to the present embodiment, some or all of the preceding vehicle 21, the utility pole 22 and the pole 23, which are obstacles existing on the traveling direction side of the vehicle 10, are moved to the operation control unit ( Since it is possible to determine with high accuracy whether the collision damage mitigation device 19 should be monitored, an increase in the processing load of the operation control unit 19 can be suppressed.

The processing and the reliability setting unit 18 for determining the reliability factor R to be monitored in accordance with the length of the detection duration oT _D obstacle, depending on the reliability index R recognizes an obstacle to be monitored and Although the process of the monitoring object recognition unit 17 for determining whether or not to operate the buzzer 12 and the brake ECU 13 is relatively simple, it can be said that the accuracy thereof is quite high. This point will be described with reference to FIG. 13 showing the results of totaling experiments conducted using five experimental vehicles equipped with a millimeter wave radar unit, a drive data recorder, a moving picture camera, and a moving picture recorder.

The graph shown in FIG. 13 shows a period during which these millimeter vehicles were captured by the millimeter wave radar unit (objects) as captured by the millimeter wave radar unit (that is, detection continuation). Period ΣT _D ) is shown separately.
In FIG. 13, the bars indicated by diagonal lines indicate the number of objects that should have been authorized as monitoring targets because the collision damage mitigation device had to be operated. On the other hand, the white bars indicate the number of objects that should not be recognized as monitoring targets because it was not necessary to activate the collision damage mitigation device. Whether or not the collision damage mitigation device needs to be activated is determined based on the results of the inventors viewing the video recorded by the video camera and video recorder, and the driving of the experimental vehicle recorded in the drive data recorder. This was done based on the condition and information obtained through interviews with the driver.

For example, when an alarm operation or an automatic braking operation is executed due to a pole or a power pole installed outside the lane in which the host vehicle is traveling, the execution of the operation makes the driver uncomfortable. Judgment was made from the viewpoint of whether or not it was felt or whether or not the alarm should have been originally given.
Then, as shown in the graph of FIG. 13, when the detection duration ΣT _D becomes 1 second or longer, the number of objects to be monitored begins to gradually increase, and when the detection duration ΣT _D becomes 4 seconds or longer. It can be seen that all objects should have been monitored.

As described above, the processing of the monitoring object recognition unit 17 and the reliability setting unit 18 in the present invention is simple, but its accuracy is considerably high.
The processing and the reliability setting unit 18 for determining the reliability of the monitoring target according to the length of the detection duration oT _D obstacle, in accordance with the reliability recognizes an obstacle for monitoring and buzzer 12 and the brake Since the process of the monitoring object recognition unit 17 for determining whether or not to operate the ECU 13 is relatively simple, an increase in the processing load of the damage reduction system ECU 14 can be suppressed.

Further, by suppressing the processing load of the operation control unit 19, the operation control unit 19 can quickly and appropriately send a command to the buzzer 12 and the brake ECU 13.
Furthermore, by suppressing the processing load of the operation control unit 19, it is possible to suppress power consumption of the damage reduction system ECU 14 and also to suppress heat generated from the damage reduction system ECU 14.

Also, depending on the length of the detection duration oT _D obstacle, by changing the reliability R of the monitoring target, it is possible to improve the operation accuracy of the operation control unit 19.
Then, as the attention level AL set by the attention level setting unit 32 decreases, the detection period threshold correction unit 33 performs the first detection period threshold T _Dth1 , the second detection period threshold T _Dth2, and the third detection period. Since the threshold value T _Dth3 is corrected so as to increase, it is possible to set the reliability R of the monitoring target in accordance with a decrease in the driver's attention.

Thereby, even in various road traffic situations, it is possible to prevent the driver from being confused and to avoid the behavior of the vehicle 10 becoming unstable.
Further, by using the reaction time map 35, the reaction time TR of the driver can be estimated quickly and accurately without using a complicated calculation or estimation method.
Further, as the reaction time TR estimated by the reaction time estimation unit 31 becomes longer, the collision threshold correction unit 34 performs the first collision threshold line C _th1 , the second collision threshold line C _th2, and the third collision threshold line C _th3. Therefore, the buzzer 12 and the brake ECU 13 can be operated at a timing earlier than the normal time as the driver's reaction time TR becomes longer.

Further, by controlling whether or not the buzzer 12 and the brake ECU 13 are to be operated according to the reliability coefficient R of the obstacle, an alarm by the buzzer 12 and warning braking and emergency braking by the brake ECU 13 are required. It can be executed appropriately in the scene.

Although the embodiments of the present invention have been described above, the present invention is not limited to such embodiments, and various modifications can be made without departing from the spirit of the present invention.

For example, in the above-described embodiment, the case where an obstacle is detected by the millimeter wave radar unit 11 has been described as an example. However, the present invention is not limited to this, and the obstacle is detected using a laser radar (infrared radar) or a camera. May be detected.
In the above-described embodiment, the case where the damage reduction system ECU 14, the millimeter wave radar unit 11, the buzzer 12, and the brake ECU 13 are connected by a CAN standard communication cable has been described as an example. It is not limited to. For example, connection may be made using a communication cable that matches any communication standard such as LIN (Local Interconnect Network) standard or IDB-1394 standard.

  Moreover, in the above-mentioned embodiment, although the case where the operation control part 19 controlled the buzzer 12 and brake ECU13 was demonstrated, it is not limited to this. For example, the operation control unit 19 may control the seat belt pretensioner to give a warning to the driver or to restrain the driver more reliably.

1 is a schematic block diagram mainly showing an overall configuration of a vehicle collision damage alleviating apparatus according to an embodiment of the present invention. It is a typical graph which shows the reliability level of the monitoring object set by the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention. It is a schematic diagram which shows the TTC map used in the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention, Comprising: The state before correction | amendment is shown. It is a schematic diagram which shows the TTC map used in the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention, Comprising: The state after correction | amendment is shown. It is a schematic diagram which shows the reaction time map used in the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention. It is a typical flowchart of the main routine which shows operation | movement of the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention. It is a typical flowchart of the main routine which shows operation | movement of the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention. 4 is a schematic flowchart of a subroutine showing an operation when the reliability is 0, in the collision damage alleviating device for a vehicle according to the embodiment of the present invention. 6 is a schematic flowchart of a subroutine showing an operation when the reliability is 1, in the collision damage alleviating device for a vehicle according to an embodiment of the present invention. 6 is a schematic flowchart of a subroutine showing an operation when the reliability is 2, in the collision damage alleviating device for a vehicle according to the embodiment of the present invention. 4 is a schematic flowchart of a subroutine showing an operation when the reliability is 3, in the vehicle collision damage alleviating apparatus according to the embodiment of the present invention. It is a schematic diagram which shows the case where the vehicle carrying the collision damage reduction apparatus of the vehicle which concerns on one Embodiment of this invention is drive | working. It is a typical graph which shows the detection accuracy of the obstruction by the collision damage reduction device of the vehicle concerning one embodiment of the present invention.

Explanation of symbols

10 Vehicle 11 Millimeter wave radar unit (obstacle detection means)
12 Buzzer (equipment)
13 Brake ECU (equipment)
14 Damage reduction system ECU
16 Detection period calculation unit (detection period calculation means)
17 Monitoring target certification department (monitoring target certification means)
18 Reliability setting section (Reliability setting means)
19 Operation control unit (collision time estimation means, operation control means)
31 Reaction time estimation unit (reaction time estimation means)
32 Attention level setting part (attention index setting means)
33 Detection period threshold correction unit (detection period threshold correction means)
34 Collision threshold correction unit (collision threshold correction means)
35 Reaction time map R reliability coefficient oT _D detection duration TR reaction time TD _th1 first detection period threshold value (detection period threshold)
TD _th2 second detection period threshold (detection period threshold)
TD _th3 third detection period threshold (detection period threshold)
C _th1 first collision threshold (collision threshold)
C _th2 second collision threshold (collision threshold)
C _th3 Third collision threshold (collision threshold)

Claims (4)

A vehicle collision damage reduction device that monitors obstacles existing in the traveling direction of a vehicle and activates equipment provided in the vehicle according to the possibility of collision with the monitored obstacles,
Obstacle detection means for detecting, as an obstacle, an object that is mounted on the vehicle and that may collide with the vehicle among objects existing on the traveling direction side of the vehicle;
Detection period calculation means for calculating a period during which the object is continuously detected as the obstacle by the obstacle detection means as a detection continuation period;
Monitoring object recognition means for determining whether the obstacle is to be monitored by the collision damage mitigation device and whether to operate the equipment according to the detection duration calculated by the detection period calculation means; ,
A reliability index setting means for determining that there is a possibility of a collision with the obstacle when the detection duration is greater than a predetermined detection period threshold, and setting a reliability index;
Attention index setting means for setting an attention index that decreases as the driver's attention decreases;
A collision damage alleviating device for a vehicle, comprising: detection period threshold value correcting means for increasing and correcting the detection period threshold value as the attention index set by the attention index setting means decreases. A reaction time map that defines a relationship in which the driver's reaction time increases as the attention index decreases;
2. The vehicle according to claim 1, further comprising reaction time estimating means for estimating the reaction time by applying the attention index set by the attention index setting means to the reaction time map. Collision damage reduction device. A collision time estimation means for estimating a collision prediction time until the vehicle collides with the obstacle;
An operation control means for activating the equipment when the estimated collision time estimated by the collision time estimation means falls below a predetermined collision threshold;
3. The collision damage reducing apparatus for a vehicle according to claim 2, further comprising: a collision threshold correcting unit that increases and corrects the collision threshold as the reaction time estimated by the reaction time estimating unit increases. The equipment includes an alarm device that issues an alarm to the driver, and an automatic braking device that brakes the vehicle regardless of the driver's intention,
As the detection period threshold, a first detection period threshold and a second detection period threshold larger than the first detection period threshold are set,
The monitoring object recognition means is:
When the detection duration of the obstacle exceeds the second detection period threshold, the obstacle is set as an operation target of the alarm device and the automatic braking device,
When the obstacle detection duration is less than the first detection period threshold, the obstacle is not set as an operation target of the alarm device and the automatic braking device,
When the obstacle detection continuation period is not less than the first detection period threshold and not more than the second detection period threshold, the obstacle is set as an operation target of the alarm device and the automatic brake device is operated. The collision damage reducing device for a vehicle according to any one of claims 1 to 3, wherein

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