JP5949786B2 - Pedestrian collision detection system - Google Patents

Description

  The present invention relates to a pedestrian collision detection system.

  In order to activate a pedestrian protection device such as a pop-up hood that lifts the rear end of the hood at the time of a collision or a hood airbag that deploys an airbag on the rear end side of the hood, a collision between the vehicle and the pedestrian is detected (discriminated). It will be necessary. For example, Patent Document 1 includes a pressure chamber having a hollow inside disposed in a front bumper and a pressure sensor that detects the atmospheric pressure in the pressure chamber, and the pressure sensor receives the impact received by the front bumper. A collision detection device that detects a change in atmospheric pressure is disclosed.

  In addition, it is also determined whether the vehicle collided with a person such as a pedestrian or a road obstacle such as a roadside marker. For example, in the collision detection device described in Patent Document 1, the effective mass of the collision object is calculated from the load on the front bumper calculated from the change in the atmospheric pressure in the pressure chamber and the vehicle collision speed detected by the vehicle speed sensor. When the effective mass exceeds a predetermined threshold, it is determined that the collision object is a pedestrian.

  However, the effective mass calculated as described above may vary depending on where the collision object collides with the front bumper. For example, in the corner part of the front bumper, the load due to the collision does not act perpendicularly to the pressure chamber provided in the bumper cover, and the change in atmospheric pressure in the pressure chamber collides with the center part of the front bumper. Get smaller. As a result, when the pedestrian collides with the corner of the front bumper, even if the collision speed is the same as when the pedestrian collides with the center of the front bumper, the calculated effective mass becomes small and the front bumper Interpersonal collisions at corners may be misjudged as objective collisions.

  In order to avoid such misjudgment, a different threshold is set for the collision at the front bumper center and the collision at the front bumper corner, and the threshold is set according to where the collision object collided. It is possible to use them properly.

  In Patent Document 2, a collision is detected by three G (gravity) sensors that are provided at predetermined intervals on a load transmitting portion (for example, the back surface of the bumper cover) that moves backward upon a collision with a front bumper and detects acceleration. Bumper structures for vehicles that can be used have been proposed.

  In Patent Document 3, an optical fiber sensor and a plurality of touch sensors are provided on the front surface of a bumper reinforcement, a collision position in a front bumper is detected by the touch sensor, and an output value of the optical fiber sensor is determined according to the detected collision position. There has been proposed a collision detection device for correcting the above.

Japanese Patent No. 5252077 JP 2010-260516 A JP 2007-137336 A

  As described above, in the collision detection device described in Patent Document 1, the effective mass calculated based on the change in atmospheric pressure in the pressure chamber can change depending on where the collision object collides with the front bumper. Therefore, the collision position in the front bumper is detected using the G sensor in Patent Document 2 and the touch sensor in Patent Document 3, respectively.

  However, in the vehicle bumper structure described in Patent Document 2, only the G sensor is used for collision detection. The G sensor is a sensor that detects the acceleration applied to the vehicle. However, when the vehicle travels on a rough road, a similar signal is output at the time of a collision. It was.

  The collision detection device described in Patent Document 3 corrects the output value of the optical fiber sensor in accordance with the collision position detected by the touch sensor, so that the human collision occurs not only in the central part of the front bumper but also in the same corner part. Can be determined. However, it is necessary to provide a plurality of touch sensors in order to detect the collision position, and as a result, there is a problem that the manufacturing cost of the vehicle increases.

  In view of the above facts, the present invention has an object to provide a pedestrian collision detection system that determines a collision position in a front bumper with a simple structure and accurately determines an interpersonal collision according to the determined collision position. And

The pedestrian collision detection system according to claim 1 is a bumper reinforcement in which a front end portion of a vehicle is arranged along a vehicle width direction, and an outer end portion in the vehicle width direction extends outward in the vehicle width direction from a front side member. A flexible hollow structure which is disposed along the vehicle width direction on the front surface of the ment and whose end reaches the outer end, and detects a pressure change inside the hollow structure and outputs a signal based on the pressure change. a pressure detection unit for outputting, wherein the bumper reinforcement and the rear surface of the bumper cover covering the hollow structure, the bumper reinforcement outside and in the vehicle width direction than the vehicle width direction outer end portion of, than the bumper reinforcement provided above, the acceleration detection unit outputting a signal based on the change in acceleration of the vehicle, based on a signal the acceleration detection unit has output Together determine the collision position in Rontobanpa, and a, a determination unit for determining the presence or absence of interpersonal collision based on a signal the pressure detecting portion is output.

  The pedestrian collision detection system according to claim 1 has a hollow structure whose internal pressure changes due to an impact at the time of collision on the front surface of the bumper reinforcement, and detects the internal pressure change in the hollow structure. An internal pressure detector that outputs a signal based on the pressure change is provided. Further, an acceleration detection unit that outputs a signal based on a change in the acceleration of the vehicle is provided outside the position corresponding to the front side member on the back surface of the bumper cover in the vehicle width direction.

  The determination unit determines a collision position in the front bumper based on the signal output from the acceleration detection unit. Furthermore, the determination unit determines whether or not there is a personal collision based on the signal output from the internal pressure detection unit.

  In this way, the collision position in the front bumper is determined based on the detection result of the acceleration detection unit suitable for position detection, and the interpersonal collision is based on the detection result of the internal pressure detection unit that outputs a signal having a different intensity depending on the mass of the collision object. The presence or absence of can be determined.

In the pedestrian collision detection system according to claim 1, by providing the acceleration detection unit on the outer side in the vehicle width direction than the outer end portion in the vehicle width direction of the bumper reinforcement, the collision at the corner portion can be easily discriminated. Yes. Furthermore, by disposing the acceleration detection unit above the bumper reinforcement, the acceleration detection unit is prevented from coming into contact with the bumper reinforcement at the time of a collision and being damaged.

The pedestrian collision detection system according to claim 2 is the pedestrian collision detection system according to claim 1, wherein the hollow structure is a box-shaped chamber disposed along the vehicle width direction on the front surface of the bumper reinforcement. It is a tubular tube.

The pedestrian collision detection system according to claim 2 can be provided with a box-shaped chamber or a tubular tube according to the form of the bumper reinforcement front surface.

Pedestrian collision detection system according to claim 3 is the invention according to claim 1 or 2, further comprising a speed detection unit outputting a signal based on the change in the velocity with which senses the speed of the vehicle, the The determination unit includes a displacement amount of the vehicle at the time of collision calculated based on a signal output from the acceleration detection unit, and a collision speed that is a speed of the vehicle at the time of collision calculated from a signal output from the speed detection unit. From this, it is determined whether or not the collision position in the front bumper is a corner portion of the front bumper.

The pedestrian collision detection system according to claim 3 calculates the collision speed from the detection result of the speed detection unit, and the displacement amount of the vehicle at the time of collision from the acceleration detected by the acceleration detection unit. Then, it is possible to accurately determine whether or not the collision position in the front bumper is a corner portion of the front bumper from the calculated relationship between the collision speed and the displacement amount.

The pedestrian collision detection system according to claim 4 is the pedestrian collision detection system according to claim 3 , wherein the determination unit is configured to determine the effective mass of the collision object at the time of collision from the signals output from the internal pressure detection unit and the speed detection unit, respectively. When the collision position is the corner portion of the front bumper, the calculated effective mass is a threshold value at the time of the corner portion collision, and when the collision position is other than the corner portion of the front bumper. Discriminates a human collision when each of the other thresholds is exceeded.

The pedestrian collision detection system according to claim 4 calculates the effective mass of the collision object based on the detection results of the speed detection unit and the internal pressure detection unit. Then, different threshold values are used depending on whether the collision position is the corner portion of the front bumper or other cases, and when the calculated effective mass exceeds the threshold value, it is possible to determine that the collision is an interpersonal collision.

According to the pedestrian collision detection system according to claim 1, the collision position in the front bumper is determined by a simple structure including the internal pressure detection unit and the acceleration detection unit, and interpersonal collision is accurately performed according to the determined collision position. Can be distinguished well. In addition, by providing the acceleration detection unit at a corner portion near the end in the vehicle width direction on the back surface of the bumper cover, it is possible to accurately determine a collision at the corner portion of the front bumper.

  According to the pedestrian collision detection system according to claim 2, the collision position in the front bumper is determined by a simple structure including a chamber or a tube disposed in front of the bumper reinforcement, and according to the determined collision position. Therefore, it is possible to accurately determine the interpersonal collision.

According to the pedestrian collision detection system according to the third aspect , it is possible to accurately determine the collision position in the front bumper.

According to the pedestrian collision detection system according to the fourth aspect , it is possible to accurately determine the interpersonal collision by properly using the threshold according to the determined collision position.

It is the partially broken top view which shows typically the whole front bumper to which the bumper structure for vehicles provided with the pedestrian collision detection system which concerns on this Embodiment was applied. FIG. 2 is an enlarged cross-sectional view of the front bumper shown in FIG. 1 taken along line 2-2 of FIG. FIG. 3 is an enlarged cross-sectional view of the front bumper shown in FIG. 1 taken along line 3-3 in FIG. 1. It is the schematic which shows the relationship between the position of G sensor, the collision position of a front bumper, and the displacement maximum value of a vehicle in the pedestrian collision detection system which concerns on this Embodiment. It is the schematic which shows an example of the collision position determination map for determining the collision position of a front bumper based on the collision speed and the maximum displacement value of the vehicle in the pedestrian collision detection system according to the present embodiment. In the pedestrian collision detection system which concerns on this Embodiment, it is the schematic which showed an example in the case of determining the interpersonal collision in the center part of a front bumper from the relationship between a collision speed and the effective mass of a collision body. In the pedestrian collision detection system which concerns on this Embodiment, it is the schematic which showed an example in the case of determining the interpersonal collision in the corner part of a front bumper from the relationship between a collision speed and the effective mass of a collision body. It is the flowchart which showed an example of the process which concerns on the discrimination of the interpersonal collision of the pedestrian collision detection system which concerns on this Embodiment.

  Hereinafter, the front bumper 12 including the pedestrian collision detection system 10 according to the present embodiment will be described with reference to FIGS. The pedestrian collision detection system 10 in the present embodiment corresponds to the pedestrian collision detection system of the present invention. In addition, an arrow FR appropriately shown in the drawings indicates the vehicle front side, and an arrow LH indicates the vehicle left side (left side in the vehicle width direction).

  As shown in FIG. 1, the front bumper 12 is arranged at the front end of the vehicle (automobile), and the collision with the front bumper 12 (presence / absence) is determined by the pedestrian collision detection system 10. . This will be specifically described below.

  The front bumper 12 includes a bumper reinforcement (hereinafter referred to as “bumper R / F”) 14 which is a bumper skeleton member. The bumper R / F 14 is made of, for example, a metal material such as iron or aluminum, and is configured as a skeleton member arranged with the vehicle width direction as a longitudinal direction. The bumper R / F 14 is supported by the vehicle body across the front ends of the pair of left and right front side members 16 constituting the skeleton member on the vehicle body side via the pair of left and right crash boxes 36.

  The crash box 36 is a cylindrical member provided between the front end portion of the front side member 16 and the end portion of the bumper R / F 14 in the longitudinal direction, and is a predetermined member from the bumper R / F 14 to the vehicle rear side. When a collision load greater than the value is input, it undergoes axial compression deformation.

  Further, the left and right outer end portions of the bumper R / F 14 in the vehicle width direction extend outward in the vehicle width direction from the front side member 16, and the front of the vehicle at the left and right outer end portions of the bumper R / F 14. An angle R is formed on the side corner 14A in plan view.

  In the vehicle width direction of the front surface 14B (vehicle front-rear direction outer surface) of the bumper R / F 14, a pressure-sensitive member 20 related to detection of pressure received by the front bumper 12 at the time of a collision is elongated with the vehicle width direction as a longitudinal direction. Is formed. The pressure-sensitive member 20 includes a pressure tube 104 that is a long flexible tubular body, and the pressure tube 104 is covered with an upper absorber 32A made of a foamed resin material or a synthetic resin material. The pressure tube 104 is configured as a hollow structure having a substantially annular cross section, and the outer end in the vehicle width direction of the pressure tube 104 reaches the outer end in the vehicle width direction of the bumper R / F 14. Further, pressure sensors 28 </ b> A and 28 </ b> B (which are elements grasped as “detectors” in a broad sense) are connected to the left and right ends of the pressure tube 104, respectively. The pressure sensors 28 </ b> A and 28 </ b> B output a signal corresponding to a pressure change in the pressure tube 104 when the pressure tube 104 is deformed to an ECU (Electronic Control Unit) 30.

  Further, G sensors 106A and 106B for detecting a change in acceleration applied to the vehicle are provided on the back surface of the bumper cover 34, and the G sensors 106A and 106B each output a signal corresponding to the detected change in acceleration to the ECU 30. . The G sensors 106A and 106B are provided on the outer side in the vehicle width direction of the front side member 16, the outer side in the vehicle width direction of the crash box 36, or the outer side in the vehicle width direction of the bumper R / F 14.

  As shown in FIG. 2, the pressure tube 104 is configured as a tubular hollow structure. Further, the pressure tube 104 is attached to the upper absorber 32A by being fitted in a concave groove formed along the back surface of the upper absorber 32A provided inside the bumper cover 34 on the front side of the bumper R / F 14. It has been.

  The upper absorber 32A is made of a foamed resin material such as urethane foam, is formed in a substantially long shape with the vehicle width direction as the longitudinal direction, and is disposed along the bumper R / F 14 in plan view. The rear end portion of the upper absorber 32A is fixed (contacted) to the front surface 14B of the bumper R / F14. By fixing the upper absorber 32A to the front surface 14B of the bumper R / F 14, the pressure tube 104 is attached to the front surface 14B of the bumper R / F 14.

  The upper absorber 32A is crushed and deformed by receiving a relatively low compressive load from the front side of the vehicle. However, since the bumper R / F 14 is a rigid body, it does not easily deform even when subjected to a relatively low compressive impact. As a result, the pressure tube 104 is compressed by being sandwiched between the upper absorber 32A that is deformed and the bumper R / F 14 that is a rigid body, and is deformed so as to be crushed. On the other hand, as shown in FIG. 1, pressure sensors 28 </ b> A and 28 </ b> B are provided at the left and right ends of the pressure tube 104, and the pressure sensors 28 </ b> A and 28 </ b> B are electrically connected to the ECU 30. The pressure sensors 28 </ b> A and 28 </ b> B output a signal corresponding to the internal pressure of the pressure tube 104 to the ECU 30.

  The ECU 30 calculates a collision load based on output signals from the pressure sensors 28A and 28B. In addition, a vehicle speed sensor (not shown) is electrically connected to the ECU 30. The vehicle speed sensor outputs a signal corresponding to the collision speed with the collision body to the ECU 30, and the ECU 30 calculates the collision speed based on the output signal of the vehicle speed sensor. Then, the ECU 30 calculates the effective mass of the collision object from the calculated collision load and collision speed, determines whether the effective mass exceeds a threshold value, and determines whether the collision object to the front bumper 12 is a pedestrian. It is discriminated whether it is a person other than a pedestrian (for example, a roadside marker or a road obstacle such as a post cone).

  Further, in the present embodiment, the front bumper 12 is provided with the opening 24 for installing the auxiliary light or for guiding the air to the radiator, so that the enlargement along the line 2-2 in FIG. In FIG. 2, which is a cross-sectional view, the front bumper 12 is depicted as being divided into two parts in the vertical direction. The lower structure shown in FIG. 2 includes a lower absorber 32 </ b> B and a bumper cover 34 fixed (contacted) to the front surface 140 </ b> B of the front member (second member) 140. The lower absorber 32B is made of a foamed resin material such as urethane foam or a synthetic resin material, like the upper absorber 32A.

  Furthermore, the front bumper 12 includes a bumper cover 34 made of a synthetic resin material or the like. The bumper cover 34 is disposed so as to face the upper absorber 32A and the lower absorber 32B, and is fixedly supported to the vehicle body at a portion not shown. Further, both side portions of the bumper cover 34 in the vehicle width direction are curved toward the rear side of the vehicle as it goes outward in the vehicle width direction in plan view.

  FIG. 3 is an enlarged cross-sectional view taken along line 3-3 of the front bumper 12 shown in FIG. 1, and is an enlarged side cross-sectional view of a so-called corner portion of the front bumper 12 in the vehicle width direction. A G sensor 106 </ b> A is provided on the back surface of the bumper cover 34, and the G sensor 106 </ b> A is electrically connected to the ECU 30. In the present embodiment, the G sensor 106A (and the G sensor 106B) is provided on the back surface of the bumper cover 34 corresponding to a position above the bumper R / F 14.

  Instead of the pressure tube 104 shown in FIG. 2, for example, a pressure chamber manufactured by blow molding or the like and configured as a hollow structure with the vehicle width direction as a longitudinal direction may be provided. Similar to the pressure tube 104, the pressure chamber is fixedly attached to the front surface 14 </ b> B of the bumper R / F 14.

  The pressure chamber is rigidly attached to the bumper R / F 14 and has a rigidity capable of maintaining the shape thereof, and has a communication hole communicating with the atmosphere. Therefore, normally (statically) the pressure chamber is at atmospheric pressure. The pressure chamber receives a relatively low compressive load from the front side of the vehicle and is crushed while letting air escape from the communication hole, and the volume of the pressure chamber is reduced while dynamically changing the internal pressure of the pressure chamber. Yes.

  The pressure chamber is provided with a pressure sensor, and the pressure sensor is electrically connected to the ECU 30. And a pressure sensor outputs the signal according to the internal pressure of a pressure chamber to ECU30. As described above, the ECU 30 calculates the collision load and the effective load based on the output signal of the pressure sensor.

  In the description of the claims, the internal pressure detection unit is the pressure sensors 28A and 28B, the acceleration detection unit is the G sensors 106A and 106B, the determination unit is the ECU 30, and the speed detection unit is a vehicle speed sensor (not shown). Corresponds to each.

  Next, the operation and effect of the present embodiment will be described. FIG. 4 is a schematic diagram showing the relationship between the position of the G sensor 106A, the collision position of the front bumper 12, and the maximum displacement of the vehicle in the pedestrian collision detection system 10 according to the present embodiment. As shown in FIGS. 1 and 3, the G sensor 106 </ b> A is provided on the back surface of the bumper cover 34 outside the bumper R / F 14 in the vehicle width direction and above the bumper R / F 14. In FIG. 4, the horizontal center position of the front bumper 12 is indicated by “0” on the horizontal axis, and the G sensor mounting position is determined from the horizontal center position of the front bumper 12 as indicated by “−B” in FIG. It is a location left to the left in dimension B. 2B, which is a multiple of the dimension B, is a value that is larger than the width of the bumper R / F 14 in the vehicle width direction and smaller than the maximum width of the front bumper 12.

The vertical axis in FIG. 4 indicates the maximum value (hereinafter referred to as the vehicle displacement amount S) obtained by double integration with the acceleration a detected by the G sensor 106A as a variable as shown in the following equation (1). This is referred to as “maximum displacement value”. The displacement amount S of the vehicle can be regarded as the deformation amount of the front bumper if the collision object collides with the front bumper and the vehicle body does not deform due to the impact caused by the collision.
S = ∬adtdt (1)

  Further, the horizontal axis of FIG. 4 shows the collision position of the front bumper 12 in association with the above-described left and right center position “0” of the front bumper 12 and “−B” which is the mounting position of the G sensor 106A. . The G sensor 106B is mounted at the position “B” on the horizontal axis. The maximum displacement value based on the detection result of the G sensor 106B is different from the result shown in FIG. It is substantially bilaterally symmetric with respect to the center position “0”. Therefore, hereinafter, the case of the G sensor 106A will be described with reference to FIG. 4, and a detailed description of the case of the G sensor 106B will be omitted.

  As shown in FIG. 4, the maximum displacement value is maximum when the collision position is the corner portion of the front bumper 12 near the G sensor 106A mounting position, and decreases as the collision position moves away from the corner portion of the front bumper 12. I will do it. In the present embodiment, it is determined that the collision position is a corner portion of the front bumper 12 when the maximum displacement value calculated from the detection result of the G sensor 106A (and the G sensor 106B) is a predetermined value or more. Can do.

  When a collision with the front bumper 12 occurs, the G sensors 106A and 106B provided on the left and right sides of the back surface of the bumper cover 34 both detect acceleration. In the present embodiment, the G sensors 106A and 106B are calculated from the detected acceleration. The collision position of the front bumper 12 is determined based on the result of the G sensor having the larger displacement maximum value.

  FIG. 5 shows an example of a collision position determination map for determining the collision position of the front bumper 12 based on the collision speed and the maximum displacement value of the vehicle in the pedestrian collision detection system 10 according to the present embodiment. FIG. The maximum displacement value increases as the collision speed calculated from the signal output from the vehicle speed sensor increases. However, the collision speed of the front surface excluding the corner portion of the front bumper 12 (hereinafter referred to as “center portion of the front bumper 12”) is higher than that of the corner portion on which the G sensors 106A and 106B are mounted. However, the maximum displacement does not increase as much as the corner.

  As a result, as shown in FIG. 5, the maximum displacement corresponding to the collision speed indicates a corner collision displacement region 62 indicating a collision at the corner portion of the front bumper 12 and a collision at the center portion of the front bumper 12. The center collision displacement area 64 can be grouped. In the present embodiment, with reference to the collision position determination map shown in FIG. 5, the maximum displacement value and the collision speed based on the detection results of the G sensors 106A and 106B are obtained from the corner collision displacement area 62 and the center collision displacement area 64. The collision position of the front bumper 12 is determined depending on which one it belongs to.

  FIG. 6 shows an example in the case of determining the interpersonal collision at the center portion of the front bumper 12 from the relationship between the collision speed and the effective mass of the collision object in the pedestrian collision detection system 10 according to the present embodiment. FIG. FIG. 6 shows the determination of the interpersonal collision in the case where the maximum displacement value calculated from the detection results of the G sensors 106A and 106B belongs to the center collision displacement area 64 shown in FIG. In FIG. 6, when the effective mass plotted with respect to the collision speed exceeds the center collision threshold value 70 indicated by the solid line, it is determined that the collision is a person-to-person collision.

In the present embodiment, the effective mass of the collision object is calculated as follows. Since the pressure sensors 28A and 28B output a signal corresponding to the load at the time of collision (collision load), the ECU 30 calculates the collision load based on the output signals of the pressure sensors 28A and 28B. Further, the ECU 30 calculates a collision speed, which is a vehicle speed at the time of the collision, based on a signal output from the vehicle speed sensor. The ECU 30 calculates the effective mass of the collision object from the calculated collision load and collision speed. Note that. The relationship of the following equation (2) is established between the effective mass m, the collision load F (t), and the collision speed v.
m × v = ∫F (t) dt (2)

Therefore, the effective mass m can be calculated by the following equation (3) obtained by dividing the time integral value of the collision load, which is the right side of the equation (2), by the collision velocity v.
m = ∫F (t) dt / v (3)

  In FIG. 6, the plotted collision speed / effective mass 80, 82, 84, 86, and 88 all exceed the center collision threshold 70, and thus are determined to be interpersonal collisions.

  FIG. 7 shows an example in the case of determining the interpersonal collision at the corner portion of the front bumper 12 from the relationship between the collision speed and the effective mass of the collision object in the pedestrian collision detection system 10 according to the present embodiment. FIG. FIG. 7 shows discrimination of interpersonal collision when the maximum displacement value calculated from the detection results of the G sensors 106A and 106B belongs to the corner collision displacement region 62 shown in FIG. In FIG. 7, when the effective mass plotted against the collision speed exceeds the corner collision threshold value 72 indicated by the solid line, it is determined that the person is a human collision.

  In FIG. 7, the plotted collision speed / effective mass 90, 92, and 94 all exceed the corner collision threshold value 72, and therefore, it is determined as an interpersonal collision. Further, since the collision speed / effective mass 96 is substantially equal to the corner collision threshold 72, it is also determined that the collision is an interpersonal collision. However, since the collision speed / effective mass 98 is less than the corner collision threshold 72, it is not determined to be an interpersonal collision, and the collision object is determined to be an installation on the road such as a roadside marker.

  Note that the center collision threshold 70 and the corner collision threshold 72 of the present embodiment are determined through a simulation using a computer and a collision experiment using an actual vehicle.

  FIG. 8 is a flowchart showing an example of processing related to determination of interpersonal collision in the pedestrian collision detection system 10 according to the present embodiment. First, in step 400, the detection results of the G sensors 106A and 106B, the pressure sensors 28A and 28B, and the vehicle speed sensor are acquired. In step 402, the maximum displacement value of the vehicle is calculated from the detection results of the G sensors 106A and 106B using the above equation (1). In step 404, the effective mass of the collision object is calculated from the detection results of the pressure sensors 28A and 28B and the vehicle speed sensor using the above-described equation (3).

  In Step 406, it is determined whether or not the collision position is a corner collision that is a corner portion of the front bumper 12 from the maximum displacement value calculated in Step 402 and the collision position determination map shown in FIG. If the determination in step 406 is affirmative, it is determined in step 408 whether or not the effective mass calculated in step 404 has exceeded the corner collision threshold 72. If the determination is affirmative, interpersonal collision is performed at the corner portion of the front bumper 12. In step 410, a pedestrian protection device (protection device) such as a pop-up hood or a hood airbag is activated to end the process.

  In the case of negative determination in step 406, it is determined that the collision position is a center collision that is the center portion of the front bumper 12, and in step 412, whether the effective mass calculated in step 404 exceeds the center collision threshold 70 or not. In the case of affirmative determination, it is determined that there has been an interpersonal collision at the center portion of the front bumper 12, and in step 410, a pedestrian protection device such as a pop-up hood or a hood airbag is operated, and the process is terminated.

  If the determination in step 408 or step 412 is negative, the process ends without operating a pedestrian protection device such as a pop-up hood or a hood airbag.

  As described above, according to the present embodiment, the collision position in the front bumper is determined by the simple structure including the pressure sensors 28A and 28B, the G sensors 106A and 106B, and the vehicle speed sensor. It is possible to accurately determine the interpersonal collision by the control according to the above.

  In the flowchart of FIG. 8, it is determined whether or not the collision position is a corner collision that is a corner portion of the front bumper 12 in Step 406, but whether or not the collision position is a center collision that is the center portion of the front bumper 12 in Step 406. It may be determined. If the determination in step 406 is affirmative, it is determined in step 408 whether or not the effective mass calculated in step 404 has exceeded the center collision threshold 70. If the determination is affirmative, the center portion of the front bumper 12 is determined. It is determined that there was a personal conflict. In the case of negative determination in step 406, it is determined in step 412 whether or not the effective mass calculated in step 404 has exceeded the corner collision threshold 72, and in the case of positive determination, the corner of the front bumper 12 is determined. It is determined that there has been a personal collision.

  As described above, according to the present embodiment, it is possible to determine the collision position in the front bumper with a simple structure, and to accurately determine the interpersonal collision by the control according to the determined collision position.

10 Pedestrian collision detection system 12 Front bumper 14 Bumper reinforcement (Bumper R / F)
16 Front side member 28A, 28B Pressure sensor (internal pressure detection part)
30 ECU
34 Bumper cover 36 Crash box 62 Corner collision displacement area 64 Center collision displacement area 70 Center collision threshold 72 Corner collision threshold 104 Pressure tube (hollow structure)
106A, 106B G sensor

Claims (4)

It is arranged along the vehicle width direction on the front surface of the bumper reinforcement that is arranged along the vehicle width direction at the front end portion of the vehicle, and whose outer end portion in the vehicle width direction extends outward from the front side member in the vehicle width direction. A flexible hollow structure whose end reaches the outer end; and
An internal pressure detector that detects a pressure change inside the hollow structure and outputs a signal based on the pressure change;
The vehicle is provided on the back surface of a bumper cover that covers the bumper reinforcement and the hollow structure, on the outer side in the vehicle width direction of the bumper reinforcement on the outer side in the vehicle width direction and above the bumper reinforcement. An acceleration detector that outputs a signal based on a change in acceleration of
A determination unit that determines a collision position in a front bumper based on a signal output from the acceleration detection unit, and determines whether or not there is a human collision based on a signal output from the internal pressure detection unit,
Pedestrian collision detection system with   2. The pedestrian collision detection system according to claim 1, wherein the hollow structure is a box-shaped chamber or a tubular tube disposed along a vehicle width direction on a front surface of the bumper reinforcement. A speed detection unit that detects a speed of the vehicle and outputs a signal based on the change in the speed;
The discriminating unit is a collision speed, which is a vehicle speed at the time of collision calculated from a displacement amount of the vehicle at the time of collision calculated based on a signal output from the acceleration detection unit and a signal output from the speed detection unit. 3. The pedestrian collision detection system according to claim 1, wherein the collision position in the front bumper is determined as to whether or not a corner portion of the front bumper. The determination unit calculates an effective mass of a collision object at the time of collision from signals output from the internal pressure detection unit and the speed detection unit, and the calculated effective mass is determined so that the collision position is the corner of the front bumper. 4. The walking according to claim 3 , wherein a threshold value at the time of a corner collision is determined in the case of a part, and an interpersonal collision is determined when each of the collision positions exceeds the other threshold value in a case other than the corner part of the front bumper. Collision detection system.

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