JP2002036994A - Obstacle estimation device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately estimate the type of an obstacle with which a vehicle came into collision in a short time. SOLUTION: This obstacle estimation device for a vehicle is provided with a bumper face which deforms according to impact force collided with the obstacle, a deformation speed detection means 51 which detects deformation speed of the bumper face, a timer starting means 52 which starts a timer at the time when the deformation speed reaches the first reference speed during accelerating, a maximum value of deformation speed update means 53 which compares the deformation speed with the maximum value of the old deformation speed detected before this and defines the larger one as the maximum value of the deformation speed, a second reference speed generation means 54 which makes the second reference speed by multiplying the maximum value of the deformation speed by a constant being less than 1.0, a elapsed time calculating means 55 which stops the timer at the time when the deformation speed reaches the second reference speed and determines elapsed time from start of the timer to stop thereof, and an estimation signal generation means 56 which estimates a specific obstacle when the elapsed time is within a predetermined time range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle obstacle estimating apparatus for estimating the type of an obstacle when the vehicle collides with the obstacle.

[0002]

2. Description of the Related Art Some vehicles are equipped with a device for estimating the type of the obstacle when the vehicle collides with the obstacle and taking measures against secondary collision such as activating an airbag near the hood according to the type. Are known. As this type of device, for example, Japanese Patent Application Laid-Open No. 8-216826 discloses a "hood airbag sensor system". Hereinafter, this conventional technique will be described.

FIGS. 16 (a) and 16 (b) show Japanese Unexamined Patent Publication No. 8-216.
FIG. 8 is an explanatory diagram created based on FIGS. 6 and 7 of Japanese Patent Publication No. 826; In addition, the names and reference numerals of the respective constituent elements were appropriately changed. (A) shows that the vehicle 101 has collided with the specific obstacle S11, such as a pedestrian. The hood airbag sensor system 100 is connected to the front bumper 10 of the vehicle 101.
2 is provided with a bumper sensor 103 and the hood 10
4 is provided with a hood sensor 105. Bumper sensor 1
03 is a sensor that detects a load from a substantially horizontal direction,
The hood sensor 105 is a sensor that detects a load from a substantially vertical direction. Food airbag sensor system 100
The control device 106 estimates that the colliding obstacle S11 is a specific obstacle and outputs a control signal to the hood airbag module 107 only when both the bumper sensor 103 and the hood sensor 105 detect a load. . In response to this control signal, the hood airbag 108 near the hood 104 is inflated.

FIG. 1B shows that the vehicle 101 has collided with an obstacle S12 such as a building. When only the bumper sensor 103 detects the load, the control device 106 estimates that the colliding obstacle S12 is not a specific obstacle. In this case, since the control device 106 does not output a control signal to the hood airbag module 107, the hood airbag 108 does not inflate.

As described above, in the hood airbag sensor system 100, first, the bumper sensor 103 detects the load,
Next, the hood sensor 105 detects a load, estimates that the obstacle S11 is a specific obstacle based on the two detection signals, and takes measures against a secondary collision.

[0006]

The conventional food airbag sensor system 100 employs a two-stage detection method in which a load is detected by a hood sensor 105 after a load is detected by a bumper sensor 103. . However, the elapsed time from when the bumper sensor 103 detects the load to when the hood sensor 105 detects the load is not constant. If the elapsed time is long, the controller 106
However, the time required for estimating the types of the obstacles S11 and S12 must be long. It is not preferable that it takes time to estimate the types of the obstacles S11 and S12.

Further, even if the obstacle S11 is not a specific obstacle, the hood sensor 105 may detect the load after the bumper sensor 103 detects the load. In this case, the control device 106 controls the obstacle S1
1 would be incorrectly estimated to be a particular obstacle.
That is, an error may occur in the type determination of the obstacle S11. The occurrence of such an error is not desirable.

It is an object of the present invention to provide a technique capable of shortening the time required for estimating the type of an obstacle colliding with a vehicle and estimating the type of an obstacle more accurately.

[0009]

According to a first aspect of the present invention, there is provided a vehicle obstacle estimating apparatus for estimating the type of an obstacle when the vehicle collides with the obstacle.
The vehicle obstacle estimating apparatus includes a deformable member that deforms according to an impact force of the vehicle hitting the obstacle, a deformation speed detecting unit that detects a deformation speed of the deformable member, and a deformation speed detecting unit. Timer starting means for starting a timer when the detected deformation speed reaches a predetermined first reference speed during the acceleration, and the deformation speed is larger than the maximum value of the old deformation speed detected earlier. And a deformation speed maximum value updating means for determining one as the deformation speed maximum value.
A second reference speed generating means for determining a value corresponding to a value multiplied by a constant less than a second reference speed, and stopping the timer when the deformation speed reaches the second reference speed; Elapsed time calculation means for calculating the elapsed time, and estimation signal generation means for estimating that the elapsed time falls within a predetermined time range and estimating that the obstacle is a specific obstacle and emitting an estimation signal, are provided. .

The vehicle obstacle estimating device detects the deformation speed of the deformable member when the vehicle hits an obstacle, and when the deformation speed reaches a first reference speed during the acceleration, the deformation speed becomes maximum. The elapsed time from the increase to the value to the decrease to the second reference speed is obtained, and when the elapsed time falls within a predetermined time range, it is estimated that the colliding obstacle is a specific obstacle. I do. Since the type of obstacle is only estimated based on whether the elapsed time falls within a predetermined time range, the time required for estimating the type of obstacle can be extremely reduced, and the type of obstacle can be reduced. More accurate estimation can be performed.

According to a second aspect of the present invention, the estimation signal generating means issues an estimation signal to a secondary collision countermeasure device for a vehicle which takes measures against a secondary collision such as raising a hood of a vehicle or activating an airbag near the hood. Characterized in that:

[0012] When a secondary collision countermeasure device for a vehicle receives an estimated signal indicating that the vehicle is a specific obstacle from the estimated signal generating means, the secondary collision countermeasure device takes a countermeasure against a secondary collision and performs a countermeasure against the obstacle or equipment in the engine room. Absorb the impact force sufficiently. It is possible to take appropriate measures for a secondary collision more appropriately and promptly.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that "before", "after",
“Left”, “right”, “up”, and “down” follow the direction viewed from the driver, and Fr indicates the front side, Rr indicates the rear side, L indicates the left side, and R indicates the right side. Also, the drawings should be viewed in the direction of reference numerals.

FIG. 1 is a perspective view of a vehicular secondary collision countermeasure device according to the present invention. The vehicle secondary collision countermeasure device 10 is provided with an engine room 12 at a front portion of a vehicle 11 and closes an upper opening of the engine room 12 with a front-opening hood 13.
The rear end of the hood 13 is attached to the vehicle body frame 14 so as to be opened and closed by left and right hood holding mechanisms 20.
The front portion of the hood 13 can be locked to the vehicle body frame 14 by a hood lock 15. In the figure, reference numeral 16 denotes a windshield.

FIG. 2 is a system diagram of the vehicular secondary collision countermeasure device according to the present invention, in which the front half of the vehicle 11 is viewed from the left side. The vehicular secondary collision countermeasure device 10 is a device that takes a secondary collision countermeasure by raising the hood 13 when the vehicle 11 collides with the obstacle S1, and includes a left and right hood holding mechanism 20 (only left in FIG. (The same applies hereinafter.)
And the left and right actuators 30 used when lifting the rear part of the closed hood 13. Further, the vehicle secondary collision countermeasure device 10 includes a vehicle obstacle estimation device 40. Details of the vehicle obstacle estimation device 40 will be described later.

The hood holding mechanism 20 normally functions as a hinge for opening and closing the hood 13, and when the obstacle S1 collides with the vehicle 11, the hood 13 is extended by an extended link.
Is a hinge that also serves as a connecting link mechanism that determines the ascending position of the rear part. The actuator 30 receives an electric actuator drive command signal (estimated signal) s from a control unit 44 described later.
i, the gas generating agent is ignited by an ignition device (not shown) to generate a large amount of gas, and the piston 31 rises by a predetermined stroke due to the rapid pressure increase of the gas.
3 to lift the rear.

FIG. 3 is a side sectional view of a front portion of the vehicle according to the present invention.
Bumper face 4 that covers the front of this front bumper 41
2 shows that the bumper sensor 43 has been attached to the inner surface of FIG.
The bumper sensor 43 is an acceleration sensor.

A plurality (for example, three) of bumper sensors 43 may be arranged in the vehicle width direction as shown in FIG. When a plurality of bumper sensors 43 are provided, the control unit 44 performs a control action based on the detection signals of these bumper sensors 43. For example, the control unit 44 calculates an average value of the plurality of detection signals, and controls the actuator 30 based on the average value, or controls the actuator 30 based on the largest signal among the plurality of detection signals.

FIG. 4 is a block diagram and operation diagram of the bumper face and the bumper sensor according to the present invention. Bumper face 4
Reference numeral 2 denotes a deformable member that deforms according to the impact force of the vehicle 11 hitting the obstacle S1, and is, for example, a resin product. The bumper face 42 indicated by the imaginary line is deformed as indicated by the solid line according to the impact force applied to the obstacle S1. At this time, the acceleration of the deformed portion of the bumper face 42 is measured by the bumper sensor 4 attached to the bumper face 42.
3 can be detected. And the bumper sensor 43
The deformation speed of the bumper face 42 can be known by integrating the deformation acceleration detected in step (1).

The obstacle estimating device 40 for a vehicle is provided with an obstacle S1.
When the vehicle 11 collides with the vehicle, the type of the obstacle S1 is estimated, and an estimation signal si is transmitted to the vehicle secondary collision countermeasure device 10. Specifically, the vehicle obstacle estimation device 40 includes a bumper face 42 as a deformable member,
The control unit 44 includes a bumper sensor 43 and a control unit 44 that issues an estimation signal si to the actuator 30 of the vehicular secondary collision countermeasure device 10 based on a signal from the bumper sensor 43. Control unit 4
4 is a microcomputer, for example.

FIG. 5 is an operation diagram of the bumper face and the bumper sensor according to the present invention. An obstacle S2 whose ground height H2 at the center of gravity Gv is lower than the ground height H1 at the front end of the bumper face 42 (hereinafter, referred to as "low center of gravity obstacle S2").
When the vehicle 11 collides with the vehicle 11, the low center of gravity obstacle S <b> 2 may be caught in the lower part of the vehicle 11. In this case, the bumper face 42 is deformed by the entangled low center of gravity obstacle S2 so as to be pulled downward and rearward of the vehicle 11.

Next, when the bumper face 42 collides with the obstacle S1 or the low center of gravity obstacle S2, the bumper face 4
6 and 7 will be described with reference to FIG. 4 and FIG. FIG. 6 is a deformation speed graph (part 1) of the bumper face according to the present invention, in which the horizontal axis represents time and the vertical axis represents the bumper deformation speed, and represents a change in the deformation speed of the bumper face that collides with an obstacle. is there.
However, each code is defined as follows.

Curve VB1; Deformation speed waveform curve when the obstacle is a light object Curve VB2; Deformation speed waveform curve when the obstacle is a specific obstacle such as a pedestrian Curve VB3; Deformation speed waveform curve VM1; maximum deformation speed of curve VB1 VM2; maximum deformation speed of curve VB2 VM3; maximum deformation speed of curve VB3 VS; first reference speed of curves VB1, VB2, VB3 ( A value almost immediately after the collision, for example, a value slightly exceeding zero VE1; the second reference speed of the curve VB1 (the maximum deformation speed VM)
VE2; second reference speed of curve VB2 (maximum deformation speed VM)
2 1/2) VE3; second reference speed of curve VB3 (maximum deformation speed VM)
1/2 of 3) P0; VS point of curves VB1, VB2, VB3 P1; VE after curve VB1 increases from P0 to VM1
Point P2 reduced to 1; VE after curve VB2 increases from P0 to VM2
Point P3 reduced to 2; VE after curve VB3 increases from P0 to VM3
TC1; time when curve VB1 changes from P0 to P1 (elapsed time) TC2; time when curve VB2 changes from P0 to P2 (elapsed time) TC3; time when curve VB3 changes from P0 to P3 ( Elapsed time) TS: Lower limit time (predetermined elapsed time from P0) TL: Upper limit time (predetermined elapsed time from P0)

As is apparent from the graph of FIG. 6, any of the deformation speed waveform curves VB1, VB2, VB3 decreases after exceeding the first reference speed VS to the maximum deformation speed VM1, VM2, VM3. And the second reference speeds VE1, VE2,
It can be seen that it has the characteristic of passing through VE3. Moreover,
It can be seen that the deformation speed waveform curve of the lighter obstacle changes from the first reference speed to the second reference speed in a shorter time (eg, T).
C1 <TC2).

Further, as described above, when the obstacle is the low center of gravity obstacle S2 shown in FIG. 5, the bumper face 42 is deformed so as to be pulled downward and rearward of the vehicle 11. In this case, as shown by the deformation speed waveform curve VB3, the time from when the deformation speed maximum value VM3 is reached to the point P3 is changed is determined by the other deformation speed waveform curve VB3.
It turns out that it is longer than B1 and VB2. That is, the deformation speed in the deformation speed waveform curve VB3 decreases very slowly. The present inventors have developed the bumper face 4 in this manner.
It has been found that the characteristic in which the deformation speed VB of the bumper face 42 changes every moment, that is, the deformation speed waveform characteristic is different depending on the type of the obstacle hit by 2 (see FIG. 4).

Here, the lower limit time TS is set between the elapsed time TC1 and the elapsed time TC2, and the elapsed time TC2 is set.
The upper limit time TL is set between the time and the elapsed time TC3. Further, the curves VB1, VB2, and VB3 are collectively referred to as a "deformation speed waveform curve VB", VM1, VM2, and VM3 are collectively referred to as a "deformation speed maximum value VM", and VS is referred to as a "first reference speed VB".
S ", VE1, VE2, and VE3 are collectively referred to as" second reference speed VE ", and TC1, TC2, and TC3 are collectively referred to as" elapsed time TC ".

Now, assume that the vehicle collides with an obstacle.
The deformation speed waveform curve of the bumper face at this time is VB. Elapsed time TC in this deformation speed waveform curve VB
Is within a predetermined time range (between the lower limit time TS and the upper limit time TL). As described above, when the elapsed time TC falls within the predetermined time range, it is possible to estimate that the colliding obstacle is a specific obstacle. In FIG.
An obstacle having the characteristic of the deformation speed waveform curve VB2 corresponds to a specific obstacle. Note that the upper limit time TL is several tens ms.
(Milliseconds), which is extremely short.

FIG. 7 is a graph of the deformation speed of the bumper face according to the present invention (part 2), where the horizontal axis represents time and the vertical axis represents the bumper deformation speed, when the vehicle collides with the same obstacle at a high speed. This figure shows a change in the deformation speed of the bumper face when the vehicle collides with the vehicle at a low speed. However, each code is defined as follows.

Curve VB11: Deformation speed waveform curve when colliding at high speed Curve VB12: Deformation speed waveform curve when colliding at low speed VM11: Maximum deformation speed of curve VB11 VM12; Maximum deformation speed of curve VB12 VS: Curve VE1; first reference speed of VB11 and VB12 (value almost immediately after collision; for example, a value slightly exceeding zero) VE11; second reference speed of curve VB11 (maximum deformation speed VM1)
1/2 of 1) VE12; second reference speed of curve VB12 (maximum deformation speed VM1)
1/2 of 2) P01; VS point of curve VB11 P02; VS point of curve VB12 P11; VE1 after curve VB11 increases from P01 to VM11
Point P12 reduced to 1; VE1 after curve VB12 increases from P02 to VM12
The point at which the curve VB11 changes from P02 to P12 (elapsed time) TC11: The time when the curve VB11 changes from P01 to P11 (elapsed time)

As is clear from the graph of FIG. 7, the elapsed time T when the vehicle collides with the same obstacle at a high speed is shown.
The elapsed time TC12 when the vehicle collides at a low speed with respect to C11 is
It turns out that there is almost no difference. In other words, if the same vehicle collides with the same obstacle, there is a large difference between the elapsed times TC11 and TC12 when the vehicle collides with the obstacle, even if the vehicle speed at the time of the collision is different. Absent.

From this, as described with reference to FIG. 6, the deformation speed waveform curve VB of the bumper face is a curve having a characteristic falling within a predetermined time range (between the lower limit time TS and the upper limit time TL). At one time, the method of estimating that the colliding obstacle is a specific obstacle can be accurately estimated regardless of the collision speed of the obstacle (the vehicle speed at the time when the vehicle collides with the obstacle). It can be said that this is an extremely effective estimation method.

FIG. 8 is a control flowchart of the control unit according to the present invention, and shows a control flow when the control unit 44 (see FIG. 4) is a microcomputer.
In the figure, STxx indicates a step number. Hereinafter, description will be made with reference to FIGS. 4 and 6. The bumper face 42
Is described as VB.

ST01: Initialize all values (example:
Deformation speed maximum value VM = 0, elapsed time TC = 0). ST02: The deformation acceleration GB of the bumper face 42 detected by the bumper sensor 43 is read. ST03: Calculate the deformation speed VB of the bumper face 42 from the deformation acceleration GB. For example, the deformation speed VB is obtained by integrating the deformation acceleration GB.

ST04: Deformation speed VB is the first predetermined value
It is determined whether or not the reference speed VS has been reached. If YES, the process proceeds to “ST09”, and if NO, the process returns to “ST02”. ST09: Timer 4 incorporated in control unit 44 shown in FIG.
5 is reset (TC = 0). ST10: The timer 45 is started. ST11: It is determined whether or not the deformation speed VB is larger than the maximum value VM of the old deformation speed detected before this. If YES, the process proceeds to "ST12", and if NO, "ST13".
Proceed to. ST12: Determine the deformation speed VB as the maximum deformation speed VM. ST13: Second reference speed VE according to maximum deformation speed VM
Set. Specifically, the second reference speed VE is determined by the following method. A constant CV of less than 1.0 predetermined to the maximum deformation speed VM.
Is determined as the second reference speed VE (VE = VM × C
V). The second reference speed VE is determined by referring to a map shown in the following FIG. 9 according to the deformation speed maximum value VM.

FIGS. 9 (a) and 9 (b) are diagrams for explaining the second reference speed setting according to the present invention. (A) is a diagram showing a relationship between the deformation speed maximum value VM and the second reference speed VE, where the horizontal axis is the deformation speed maximum value VM and the vertical axis is the second reference speed VE. 2 shows a reference speed VE. Second reference speed V
E is a value obtained by multiplying the deformation speed maximum value VM by a predetermined constant CV of less than 1.0 (VE = VM × CV). (B)
Is a map created based on the above (a), and shows the second reference speed VE according to the deformation speed maximum value VM. As described above, the map is set in the memory of the control unit 44 (see FIG. 4) in advance, and in the above-mentioned step ST13, the second reference speed VE is set by referring to the map according to the maximum deformation speed VM. can do.

Returning to the control flowchart of FIG. 8, the description will be continued. ST14: It is determined whether or not the deformation speed VB has reached the second reference speed VE, that is, whether or not the deformation speed VB has decreased to the second reference speed VE. If YES, the process proceeds to "ST16". It returns to ST02. ST16: Stop the timer 45. ST17: Elapsed time T from start to stop of timer 45
Calculate and find C. ST18: The elapsed time TC is within a predetermined time range, that is,
It is determined whether or not it falls between a predetermined lower limit time TS and an upper limit time TL. If YES, the process proceeds to “ST19” and NO
If so, the process proceeds to “ST20”. ST19: The obstacle S1 with which the vehicle 10 has collided is estimated to be a specific obstacle, and an estimated signal si (for example, an actuator drive command signal si) is issued, and the control ends. ST20: Reset the deformation speed maximum value VM = 0 and the elapsed time TC = 0, and return to "ST02".

Here, a more specific configuration of the vehicle obstacle estimating device 40 will be described with reference to FIG. The vehicle obstacle estimation device 40 includes the following (1) to (7). (1) Bumper face 42 as a deformable member (FIG. 4)
reference). (2) Deformation speed detecting means 51 for detecting the deformation speed VB of the bumper face 42. The deformation speed detecting means 51 includes a bumper sensor 43 (see FIG. 4) and steps ST02 to ST02.
03 combinations. (3) When the deformation speed VB detected by the deformation speed detecting means 51 reaches a predetermined first reference speed VS during acceleration,
Timer starting means 5 for starting timer 45 (see FIG. 4)
2. The timer starting means 52 determines whether or not steps ST04, ST0
9 and ST10.

(4) Deformation speed maximum value updating means 53 for comparing the deformation speed VB with the maximum value VM of the previous deformation speed detected earlier, and determining the larger one as the deformation speed maximum value VM. The deformation speed maximum value updating means 53 performs steps ST11 and S11.
It consists of a combination of T12. Steps ST11 and ST1
According to 2, each time the deformation speed VB increases, the deformation speed maximum value VM
Is updated to the largest value, it is possible to set the deformation speed maximum value VM according to the type of the obstacle S1.

(5) Second reference speed generating means for determining a value corresponding to a value obtained by multiplying the maximum deformation speed VM by a constant CV of less than 1.0, for example, 0.4 to 0.6, as the second reference speed VE. 5
4. The second reference speed generating means 54 includes step ST13. This is because if the constant CV is too small or too large than 0.4 to 0.6, the accuracy for estimating the specific obstacle S1 decreases. (6) Elapsed time calculating means 55 for stopping the timer 45 when the deformation speed VB reaches the second reference speed VE and obtaining the elapsed time TC from the start of the timer to the stop. The elapsed time calculation means 55 comprises a combination of steps ST14, ST16 and ST17. (7) Estimation signal generating means 5 for estimating a specific obstacle S1 and generating an estimation signal si when the elapsed time TC falls within a predetermined time range (between the lower limit time TS and the upper limit time TL).
6. The estimation signal generation means 56 performs steps ST18 to ST18.
It consists of 20 combinations.

As is clear from the above description, according to the vehicle obstacle estimating apparatus 40, (1) the vehicle 1
The deformation speed VB of the bumper face 42 at the time of hitting 1 is detected. (2) The deformation speed VB has increased to a maximum deformation speed VM from the time when the deformation speed VB reached a predetermined first reference speed VS during acceleration. The elapsed time TC until the second reference speed VE is reduced afterwards is obtained. (3) When the elapsed time TC falls within a predetermined time range, that is, between the lower limit time TS and the upper limit time TL. In addition, it can be estimated that the colliding obstacle S1 is a specific obstacle (for example, a pedestrian).

As described above, when the bumper face 42 as a deformable member hits the obstacle S1, the vehicle obstacle estimating device 40 of the present invention provides the deformation speed waveform characteristic (deformation speed VB) of the bumper face 42. This is an application of the fact that the characteristic that changes every moment varies depending on the type of the obstacle S1, such as the weight.

Accordingly, since only a single detecting means, ie, the deformation speed detecting means 51, is used to estimate the type of the obstacle S1, the number of detecting means can be reduced. In addition, since it is only necessary to detect the impact force in one direction with a single detection means, the detection time can be reduced.

Further, the deformation speed VB is equal to the first reference speed VS.
Since the elapsed time TC from the time when the vehicle speed reaches the second reference speed VE to the time when the vehicle speed reaches the second reference speed VE is obtained and the type of the obstacle S1 is only estimated based on whether or not the elapsed time TC falls within a predetermined time range, The time required for estimating the type of the obstacle S1 can be extremely reduced, and the obstacle S1 can be reduced.
Can be more accurately estimated.

Further, the second reference speed generating means 54 sets a value corresponding to a value obtained by multiplying the maximum deformation speed VM different depending on the type of the obstacle S1 by a constant CV of less than 1.0 to the second reference speed. Since VE is determined, the type of the obstacle S1 can be more accurately estimated regardless of the collision speed with respect to the obstacle S1.

FIG. 10 is a control flowchart (modification example) of the control unit according to the present invention. In the control flowchart shown in FIG. 8, between steps ST04 and ST09,
Steps ST05 to ST08 surrounded by a broken line frame are added, and step ST15 surrounded by a broken line frame is added between steps ST14 and ST16. ST05: If YES is determined in ST04, it is determined whether or not the flag F = 0, and if YES, "S
The process proceeds to "T06", and if NO, returns to "ST02". ST06: Determine whether the timer 45 is inactive,
If “YES”, the process proceeds to “ST09”, and if “NO”, “S09”
Proceed to T11 ”. ST07: If NO is determined in ST04, the flag F is set to 0 and the process proceeds to "ST08". ST08: Determine whether the timer 45 is operating,
If S, proceed to “ST11”; if NO, “ST0”
Return to "2." ST15: When a determination of YES is received in ST14, the flag F is set to 1 and the process proceeds to "ST16".

Next, the operation of the vehicular secondary collision countermeasure device 10 having the above configuration will be described with reference to FIGS. Figure 1
1 is an operation diagram (part 1) of the vehicle secondary collision countermeasure device according to the present invention, in which the hood 13 is lowered and the engine room 12
Indicates a closed normal state. At this time, the hood holding mechanism 20 is in a folded state. The hood 13 can swing up and down with the pin 21 as a fulcrum. By opening the hood 13 as indicated by the imaginary line, maintenance and inspection work of the equipment 17 stored in the engine room 12 can be performed.

FIG. 12 is an operation diagram (part 2) of the vehicular secondary collision countermeasure device according to the present invention, and shows a normal state in which the hood 13 is lowered and the engine room 12 is closed. Control unit 4
4 sends an estimation signal (actuator drive command signal) si to the actuator 30 when it estimates that the colliding obstacle S1 is a specific obstacle. Actuator 3
0 starts the lifting operation and pushes up the rear rear surface 13a of the hood 13 by projecting the piston 31 at high speed.

FIG. 13 is an operation diagram (part 3) of the vehicular secondary collision countermeasure device according to the present invention, in which the hood 13 is shown by imaginary lines by protruding the piston 31 at a predetermined maximum height at a high speed. Indicates that the object has been pushed up from the original height to the height indicated by the solid line. The hood 13 is further lifted by inertia. As the hood 13 rises, the hood holding mechanism 20 also stands up.

FIG. 14 is an operation diagram (part 4) of the vehicular secondary collision countermeasure device according to the present invention, and shows that the hood holding mechanism 20 has reached the fully opened position and has stopped swinging. Therefore, the hood 13 cannot be lifted any more.
As a result, the rear part of the hood 13 moves from the original position indicated by the imaginary line to the position indicated by the solid line by a predetermined amount (100 to 200 mm).
It just lifted. The hood holding mechanism 20 holds the hood 13 at a raised position.

The distance from the hood 13 lifted by a predetermined amount to a device 17 such as an engine housed in the engine room 12 is large. As a result, the amount of downward deformation of the hood 13 increases. For this reason, when the obstacle S1 colliding with the vehicle 11 collides with the hood 13, the lifted hood 13 is largely deformed as indicated by the imaginary line, so that the impact force can be sufficiently absorbed. . Therefore, the device 17 can be protected from the obstacle S1, and the impact on the obstacle S1 can be sufficiently reduced.

To summarize the above description, the vehicle obstacle estimating device 40, when estimating that the obstacle S1 colliding with the vehicle 11 is a specific obstacle, sends the vehicle secondary collision An estimation signal si is issued to the countermeasure device 10. The secondary collision countermeasure device 10 for a vehicle takes the estimated signal si and raises the hood 13 to take more appropriate and quick secondary collision countermeasures. The hood 13 sufficiently absorbs the impact force on the device 17 and the obstacle S1.

FIG. 15 is a system diagram of a vehicular secondary collision countermeasure device (modification) according to the present invention. The vehicular secondary collision countermeasure device 60 of the modified example takes a secondary collision countermeasure by activating the airbag 62 provided near the hood 13 when the vehicle 11 collides with the obstacle S1. The vehicle obstacle estimating device 40 estimates that the colliding obstacle S1 is a specific obstacle, and issues an estimation signal si from the control unit 44 to the airbag module 61, thereby inflating the airbag 62. it can. And the airbag 6
By taking measures against secondary collision by inflating 2, the impact force on the equipment 17 (see FIG. 14) housed in the engine room 12 and the obstacle S <b> 1 can be sufficiently absorbed by the airbag 62.

In the embodiment of the present invention,
The deformable member is not limited to the bumper face 42, and may be any member provided in the vehicle 11 so that the vehicle 11 is deformed according to the impact force applied to the obstacle S1. Further, the deformation speed detecting means 51 may be any device that detects the deformation speed VB of a deformable member such as the bumper face 42. Furthermore, in the vehicle obstacle estimation device 40,
Each value of the constant CV, the first reference speed VS, the lower limit time TS, and the upper limit time TL is arbitrary, and may be determined by appropriately setting a reference for a specific obstacle.

[0054]

According to the present invention, the following effects are exhibited by the above configuration. According to the first aspect, the deformation speed of the deformable member when the vehicle hits an obstacle is detected, and the deformation speed maximum value is obtained from the time when the deformation speed reaches a predetermined first reference speed during the acceleration. The elapsed time until the second reference speed is reached after the increase to the second reference speed is obtained, and when the elapsed time falls within a predetermined time range, it is estimated that the colliding obstacle is a specific obstacle. be able to. For this estimation, we used only a single detection means called deformation speed detection means,
The number of detection means can be reduced. In addition, since it is only necessary to detect the impact force in one direction with a single detection means, the detection time can be reduced.

Further, the elapsed time from the time when the deformation speed reaches the first reference speed to the time when the deformation speed reaches the second reference speed is determined, and whether the elapsed time falls within a predetermined time range is determined. Since only the type of the obstacle is estimated, the time required for estimating the type of the obstacle can be extremely reduced, and the type of the obstacle can be estimated more accurately.

Further, the second reference speed generating means sets the maximum deformation speed different depending on the type of the obstacle at 1.
Since the value corresponding to the value obtained by multiplying the constant less than 0 is determined as the second reference speed, the type of the obstacle can be more accurately estimated regardless of the collision speed with the obstacle.

A second aspect of the present invention provides a second collision prevention device for a vehicle for taking measures against a second collision such as raising a hood of a vehicle or activating an airbag near the hood. , The countermeasure against secondary collision can be taken more appropriately and promptly.

[Brief description of the drawings]

FIG. 1 is a vehicle secondary collision countermeasure device according to the present invention.

FIG. 2 is a system diagram of a vehicular secondary collision countermeasure device according to the present invention.

FIG. 3 is a side sectional view of a vehicle front part according to the present invention.

FIG. 4 is a configuration diagram and operation diagram of a bumper face and a bumper sensor according to the present invention.

FIG. 5 is an operation diagram of a bumper face and a bumper sensor according to the present invention.

FIG. 6 is a graph showing a deformation speed of a bumper face according to the present invention (part 1);

FIG. 7 is a deformation speed graph of a bumper face according to the present invention (part 2).

FIG. 8 is a control flowchart of a control unit according to the present invention.

FIG. 9 is an explanatory diagram of a second reference speed setting according to the present invention.

FIG. 10 is a control flowchart of a control unit according to the present invention (modification).

FIG. 11 is an operation diagram (part 1) of the vehicular secondary collision countermeasure device according to the present invention.

FIG. 12 is an operational diagram (part 2) of the vehicular secondary collision countermeasure device according to the present invention.

FIG. 13 is an operation diagram (part 3) of the vehicular secondary collision countermeasure device according to the present invention.

FIG. 14 is an operation diagram (part 4) of the vehicular secondary collision countermeasure device according to the present invention.

FIG. 15 is a system diagram of a vehicular secondary collision countermeasure device (modified example) according to the present invention.

FIG. 16 is an explanatory diagram created based on FIGS. 6 and 7 of JP-A-8-216826.

[Explanation of symbols]

10, 60: secondary collision prevention device for vehicle, 11: vehicle, 1
DESCRIPTION OF SYMBOLS 3 ... Hood, 40 ... Obstacle estimation apparatus for vehicles, 42 ... Deformable member (bumper face), 45 ... Timer, 51 ... Deformation speed detection means, 52 ... Timer starting means, 53 ... Deformation speed maximum value updating means, 54 ... Second reference speed generating means, 55
... Elapsed time calculation means, 56 ... Estimated signal generation means, 62 ...
Airbag, CV: Constant, S1, S2: Obstacle, si ...
Estimated signal, TC: elapsed time, TS: lower limit time, TL: upper limit time, VB: deformation speed, VS: first reference speed, VE: second
Reference speed, VM: Maximum deformation speed.

Claims (2)

[Claims] 1. A vehicle obstacle estimating device for estimating the type of an obstacle when the vehicle collides with the obstacle, the vehicle obstacle estimating device comprising: A deformable member that deforms in response to a force, a deformation speed detecting unit that detects a deformation speed of the deformable member,
Timer starting means for starting a timer when the deformation speed detected by the deformation speed detecting means reaches a predetermined first reference speed during the acceleration, and an old deformation speed detected before the deformation speed is detected. Deformation speed maximum value updating means for determining the larger one as the deformation speed maximum value as compared with the maximum value, and a value corresponding to a value obtained by multiplying the deformation speed maximum value by a constant less than 1.0 as the second reference speed. Second reference speed generating means, elapsed time calculating means for stopping the timer when the deformation speed reaches the second reference speed, and calculating the elapsed time from the start of the timer to the stop, An obstacle estimating device for a vehicle, comprising: an estimation signal generating means for estimating a specific obstacle as being within a time range and generating an estimation signal. 2. The apparatus according to claim 1, wherein the estimation signal generating means issues the estimation signal to a secondary collision countermeasure device for a vehicle that takes a secondary collision countermeasure such as raising a hood of a vehicle or activating an airbag near the hood. The vehicle obstacle estimating device according to claim 1, wherein: