JP6048361B2 - 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 an active hood (pop-up hood) or a cowl airbag (hood airbag) at the time of a collision, it is necessary to detect (discriminate) a collision between the vehicle and the pedestrian. For example, Patent Document 1 includes a chamber having a hollow inside between a bumper reinforcement and a bumper cover and a pressure sensor that detects the atmospheric pressure in the chamber, and the impact received by the bumper is detected by a change in the atmospheric pressure in the chamber. A vehicle collision determination device for detection is disclosed.

  Further, it is also determined whether the vehicle has collided with a person such as a pedestrian or a pylon. For example, in a system that detects an impact received by a bumper by a change in atmospheric pressure in the chamber, such as a vehicle collision determination device described in Patent Document 1, the load on the bumper calculated from the change in atmospheric pressure in the chamber It is determined whether or not a person such as a pedestrian collides.

JP 2009-298265 A

  However, even for the same pedestrian, for example, a child such as a 6-year-old child, the load on the bumper is smaller than the load when it collides with an object such as a roadside marker. There is a problem that it is difficult to accurately determine whether the objective collision occurs. In particular, at the corner portion of the front bumper, the load caused by the collision does not act perpendicularly to the chamber provided in the bumper cover, and the calculated load is likely to be smaller than when the collision occurs at the center portion of the front bumper. As a result, there is a risk that an interpersonal collision at a corner portion of the front bumper is erroneously determined as an objective collision.

  In consideration of the above facts, an object of the present invention is to provide a pedestrian collision detection system that accurately determines an interpersonal collision from a collision at a corner portion of a front bumper.

  The pedestrian collision detection system according to claim 1 includes a vehicle width at a portion including an outer end portion in the vehicle width direction of an upper absorber arranged adjacent to a front surface of a bumper reinforcement arranged with the vehicle width direction as a longitudinal direction. An upper tube that is a flexible tubular body disposed along a direction, and a lower absorber vehicle disposed adjacent to a front surface of a front member disposed below the bumper reinforcement with a vehicle width direction as a longitudinal direction A lower tube, which is a flexible tubular body disposed along the vehicle width direction in a portion including the outer end portion in the width direction, and a belt-like shape along the vehicle width direction in the portion including the outer end portion in the vehicle width direction of the upper absorber And a pressure detecting means which is turned on or off when pressed, and detects a pressure change inside the upper tube and the lower tube. Comprises a pressure detecting means for outputting a signal based on the pressure change, the.

  In the pedestrian collision detection system according to claim 1, an upper absorber is disposed on the front surface of the bumper reinforcement. In the vehicle width direction, the upper tube and the pressure detecting means that is turned on or off when pressed are provided in a portion including the outer end portion of the cushioning material in the vehicle width direction, that is, a portion corresponding to the corner portion of the front bumper. It is arranged along. A lower tube is disposed along the vehicle width direction at a position corresponding to a corner portion of a lower absorber disposed on the front surface of the front member below the bumper reinforcement. Furthermore, an internal pressure detecting means for detecting a change in pressure inside the upper tube and the lower tube and outputting a signal based on the pressure change is provided.

  As described above, the pressure detection means for detecting the pressure, the upper and lower two-stage tubes, and the internal pressure detection means for detecting the change in the pressure inside the tubes are provided at locations corresponding to the corner portions of the front bumper. Thereby, according to the aspect of the collision with the corner part of a front bumper, while a pressure detection means turns on or off, an internal pressure detection means outputs the signal based on the pressure change inside a tube. Based on this, for example, a collision with a pedestrian and a collision with an installation such as a roadside marker or a pylon can be determined.

  A pedestrian collision detection system according to a second aspect is the invention according to the first aspect, wherein the lower tube, the pressure detection means, and the upper tube are arranged in order from the front of the vehicle.

  In the pedestrian collision detection system according to the second aspect, the lower tube, the pressure detection means, and the upper tube are arranged in order from the front of the vehicle. As a result, the timing at which the pressure detecting means is turned on or off and the output value of the internal pressure detecting means differ between a pedestrian thrown out on the hood of the vehicle after a collision and an installation fixed to the ground. Based on this difference, it is possible to accurately determine a collision with a pedestrian and a collision with an installation such as a roadside marker or a pylon.

  The pedestrian collision detection system according to claim 3 is the invention according to claim 2, wherein the output value of the internal pressure detection means before and after the pressure detection means is turned on or off is compared with a predetermined threshold value. Thus, a judgment means for judging the presence or absence of the interpersonal collision is further provided.

  The pedestrian collision detection system according to claim 3 includes a determination unit that compares an output value of the internal pressure detection unit before and after the pressure detection unit is turned on or off with a predetermined threshold value. By a simple algorithm that compares the output value of the internal pressure detection means with a predetermined threshold, it is possible to accurately determine a collision with a pedestrian and a collision with an installation such as a roadside marker or a pylon.

  A pedestrian collision detection system according to a fourth aspect is the invention according to the third aspect, wherein the predetermined threshold includes a first threshold, a second threshold, and a third threshold, and the first threshold Is less than or equal to the second threshold value, and the second threshold value is less than the third threshold value, and the determination means outputs the output value of the internal pressure detection means before the pressure detection means is turned on or off. Falls below the first threshold and the output value of the internal pressure detection means after the pressure detection means is turned on or off exceeds the second threshold, or the pressure detection means is turned on or off The output value of the internal pressure detecting means before becoming over the first threshold value and the output value of the internal pressure detecting means after the pressure detecting means is turned on or off exceeds the third threshold value. It is determined that there is a person-to-person collision.

  In the pedestrian collision detection system according to a fourth aspect, the first threshold value, the second threshold value, and the third threshold value satisfying the first threshold ≦ the second threshold <the third threshold are used. The determination means determines the presence or absence of a personal collision by comparing the output value of the internal pressure detection means before and after the pressure detection means is turned on or off with the first threshold value, the second threshold value, and the third threshold value. can do.

  A pedestrian collision detection system according to a fifth aspect of the present invention is the pedestrian collision detection system according to the fourth aspect of the present invention, wherein the upper tube and the lower tube are communicated with each other, and one end of the tubular body is provided with the tube. An internal pressure detection means is provided, and the determination means is configured to determine whether the pressure detection means is turned on or off from an output value of the internal pressure detection means after the pressure detection means is turned on or off. A subtracted output value obtained by subtracting the output value of the internal pressure detecting means is calculated, and the subtracted output value is set as the output value of the internal pressure detecting means after the pressure detecting means is turned on or off.

  In the pedestrian collision detection system according to claim 5, after the pressure detection means is turned on or off, the output of the internal pressure detection means when the pressure detection means is turned on or off from the output value of the internal pressure detection means. A subtracted output value obtained by subtracting the value is calculated, and this subtracted output value is used to determine whether or not there is a personal collision. Since the subtracted output value is based on the pressure newly detected by the internal pressure detecting means after the pressure detecting means is turned on or off, the upper and lower parts are communicated by using the subtracted output value for determination. A simple configuration including one tube can be applied.

  According to the pedestrian collision detection system according to the first aspect, it is possible to determine the interpersonal collision from the collision at the corner portion of the front bumper.

  According to the pedestrian collision detection system according to the second aspect, it is possible to accurately determine the interpersonal collision from the collision at the corner portion of the front bumper.

  According to the pedestrian collision detection system according to the third aspect, it is possible to determine the presence or absence of an interpersonal collision from the collision at the corner portion of the front bumper.

  According to the pedestrian collision detection system according to the fourth aspect, it is possible to determine the presence or absence of the interpersonal collision in various modes of collision at the corner portion of the front bumper.

  According to the pedestrian collision detection system according to claim 5, whether or not there is a human collision from a collision at a corner portion of the front bumper, even in a simple configuration including a single tube in which the upper part and the lower part communicate with each other. Can be determined.

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 1st Embodiment was applied. FIG. 2 is a side cross-sectional view (a cross-sectional view taken along line 2-2 in FIG. 1) in which a vehicle width direction central portion of the front bumper shown in FIG. 1 is enlarged. FIG. 3 is an enlarged side cross-sectional view (a cross-sectional view taken along the line 3-3 in FIG. 1) of the outer side portion of the front bumper shown in FIG. It is a figure at the time of seeing through a bumper cover from the arrow 4 direction the vehicle width direction outer side part of the front bumper shown by FIG. It is a side view which shows the one aspect | mode of the collision with a pedestrian and a vehicle. It is a side view which shows the one aspect | mode of the collision with the installation thing fixed to the grounds, such as a roadside marker, and a vehicle. It is a figure which shows the one aspect | mode of the change of the output immediately after the collision of the pressure sensor provided in the pressure tube of 1st Embodiment, (A) is a case where it determines with a collision with a pedestrian, (B) is The case where it does not determine with the collision with a pedestrian is shown. It is a figure which shows the aspect different from FIG. 7 of the change of the output immediately after the collision of the pressure sensor provided in the pressure tube of 1st Embodiment, (A) is a case where it determines with a collision with a pedestrian (B) has shown the case where it is not determined that it is a collision with a pedestrian. It is a figure which shows the one aspect different from FIG. 7, FIG. 8 of the change of the output immediately after the collision of the pressure sensor provided in the pressure tube of 1st Embodiment, (A) is a collision with a pedestrian. When determining, (B) has shown the case where it does not determine with the collision with a pedestrian. It is a figure which shows an example of the flowchart of the interpersonal collision determination of the pedestrian collision detection system which concerns on 1st Embodiment. It is a figure with respect to FIG. 4 which shows an example of the modification of 1st Embodiment. It is a figure with respect to FIG. 4 which shows another example of the modification of 1st Embodiment. It is a figure with respect to FIG. 4 which shows another example of the modification shown in FIG.

(First 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 front side of the vehicle, an arrow LH indicates the left side of the vehicle (one side in the vehicle width direction), and an arrow UP indicates the upper side of the vehicle.

  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 a pair of left and right front side members 16 constituting a skeleton member on the vehicle body side. Further, both side portions in the vehicle width direction of the bumper R / F 14 slightly protrude outward in the vehicle width direction with respect to the front side member 16, and corner portions on the vehicle front side at both ends in the vehicle width direction of the bumper R / F 14. 14A has an angle R in plan view.

  A pressure-sensitive member 20 is provided on the front side of the bumper R / F 14, and the pressure-sensitive member 20 is formed in a long shape with the vehicle width direction as a longitudinal direction. The pressure-sensitive member 20 includes a chamber body 22, a pressure tube 104 that is a long and flexible tubular body, and a touch sensor 102, which are made of a foamed resin material or a synthetic resin material. It is covered with an absorber 32A. The pressure tube 104 is configured as a hollow structure having a substantially U-shaped overall shape and a substantially annular cross section. The outer end of the pressure tube 104 in the vehicle width direction is the outer side of the bumper R / F 14 in the vehicle width direction. It arrange | positions rather than the edge part in the vehicle width direction outer side. Further, a pressure sensor 28A (which is an element grasped as “detector” in a broad sense) is connected to one end of the pressure tube 104, and the other end is closed. The pressure sensor 28 </ b> A outputs 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. The touch sensor 102 is a belt-like switch that detects a pressure due to a collision and outputs the detected result to the ECU 30 as an electrical signal. In principle, the touch sensor 102 is normally turned off and is turned on when a press due to a collision is detected. However, the touch sensor 102 may be turned on normally and turned off when a press due to a collision is detected.

  As shown in FIG. 2, the chamber body 22 is configured as a hollow structure whose longitudinal direction is the vehicle width direction, and the internal space of the chamber body 22 is a pressure chamber 26. The chamber body 22 is fixedly attached to the front surface 14B (vehicle front-rear direction outer surface) of the bumper R / F14.

  Further, the pressure-sensitive member 20 has a rigidity capable of maintaining its shape in a state where the pressure-sensitive member 20 is fixedly attached to the bumper R / F 14 in the chamber main body 22, and the chamber main body 22 has a position (not shown). Has a communication hole communicating with the atmosphere. Accordingly, normally (statically) the pressure chamber 26 is at atmospheric pressure. The chamber body 22 receives a relatively low compressive load from the front side of the vehicle and is crushed while allowing air to escape from the communication hole, so that the volume of the pressure chamber 26 is reduced while dynamically changing the internal pressure of the pressure chamber 26. It has become.

  Further, in the pressure-sensitive member 20, the chamber body 22 is formed into a box-shaped hollow structure by blow molding or the like. Further, both end portions in the longitudinal direction of the chamber main body 22 formed in the box shape overlap with the end of the pressure tube 104 in a plan view in FIG.

  On the other hand, as shown in FIG. 2, a pressure sensor 28 </ b> B is provided at the center of the upper end of the chamber body 22, and the pressure sensor 28 </ b> B is electrically connected to the ECU 30 as a “collision determination unit”. Yes. The pressure sensor 28B outputs a signal corresponding to the pressure in the pressure chamber 26 to the ECU 30.

  The ECU 30 is configured to calculate the collision load based on the output signal of the pressure sensor 28B. The ECU 30 is electrically connected with a collision speed sensor (not shown). The collision speed sensor (vehicle speed sensor) outputs a signal corresponding to the collision speed with the collision object to the ECU 30, and the ECU 30 calculates the collision speed based on the output signal of the collision speed sensor. . Then, the ECU 30 obtains the effective mass of the collision object from the calculated collision load and collision speed, determines whether the effective mass exceeds the threshold value, and determines that the collision object to the center portion of the front bumper 12 is a pedestrian. Or a person other than a pedestrian (for example, a roadside marker, a post cone, etc.).

  Further, an upper absorber 32A is provided inside the bumper cover 34 on the front side of the bumper R / F 14. The upper absorber 32A is made of a foamed resin material such as urethane foam. Further, the upper absorber 32A is formed in a substantially long shape with the vehicle width direction as a longitudinal direction, and is disposed along the bumper R / F 14 in a plan view. Fixed (contact).

  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 cross section taken along line 2-2 in FIG. In FIG. 2, which is a diagram, the front bumper 12 is depicted as being divided into two vertically. 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 a 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. FIG. 3 shows an arrangement of the touch sensor 102, the pressure tube 104, the upper absorber 32A, and the lower absorber 32B in the corner portion. Inside the bumper cover 34, the upper absorber 32 </ b> A is fixed to the front surface 14 </ b> B of the bumper R / F 14, and the lower absorber 32 </ b> B is fixed to the front surface 140 </ b> B of the front member 140 in the same manner as in the central portion of the bumper. In the bumper corner portion, the touch sensor 102 and the pressure tube 104 are embedded in the upper absorber 32A, and the pressure tube 104 is embedded in the lower absorber 32B. As shown in FIG. 1, the pressure tube 104 is a single flexible tube having a substantially U shape provided so as to be folded back in the vicinity of the end in the vehicle width direction at the bumper corner portion. A portion corresponding to one side of the substantially U-shape of the pressure tube 104 is embedded in the upper absorber 32A, and the other side is embedded in a lower absorber 32B disposed below the upper absorber 32A.

  3A and 3B show the vertical positional relationship between the touch sensor 102 and the pressure tube 104 with reference to a plane (horizontal plane) A set between the upper absorber 32A and the lower absorber 32B. Further, c, d, and e indicate the positional relationship between the front and back of the touch sensor 102 and the pressure tube 104 with reference to a plane (vertical surface) B set behind the bumper R / F 14. In the present embodiment, a ≧ b, and the touch sensor 102 is embedded at the same height as the center line of the pressure tube 104 in the upper absorber 32A or higher than the center line of the pressure tube 104. In the present embodiment, c <d ≦ e, and the center line of the pressure tube 104 in the lower absorber 32B is the same as the front line of the touch sensor 102 or the front and back of the center line of the touch sensor 102. Provided in position. The center line of the pressure tube 104 in the upper absorber 32 </ b> A is provided behind the touch sensor 102. In the example of FIG. 3, the touch sensor 102 and the pressure tube 104 do not overlap in the vehicle front view and the side view.

  FIG. 4 is a view of the corner portion of the front bumper 12 shown in FIG. 1 as seen through the bumper cover 34 from the direction of the arrow 4. As shown in FIG. 4, the pressure tube 104 is disposed in a substantially U shape in the horizontal direction, and a pressure sensor 28 </ b> A is provided at the end of the pressure tube 104 positioned below, and the pressure sensor 28 </ b> A is connected to the ECU 30. Has been. A touch sensor 102 is provided above the pressure tube 104. Further, the vehicle width direction outer side position end of the chamber main body portion 22 is provided to overlap with a part of the pressure tube 104 positioned above and the touch sensor 102 in the vehicle width direction.

  In the description of the scope of claims, the upper tube corresponds to the pressure tube 104 (upper pressure tube 104) located above, and the lower tube corresponds to the pressure tube 104 (lower pressure tube 104) located below. The pressure detection means corresponds to the touch sensor 102, and the internal pressure detection means corresponds to the pressure sensor 28A.

  Next, the operation and effect of the present embodiment will be described. As shown in FIG. 3, the pressure tube 104 positioned below is provided in front of the vehicle with respect to the touch sensor 102, so if there is any collision at the corner of the front bumper 12, The pressure tube 104 is pressed, and after the touch sensor 102 detects a collision, the upper pressure tube 104 is pressed.

  In the present embodiment, depending on what the vehicle has collided with, the difference in the strength of the signal output from the pressure sensor 28A provided in the pressure tube 104 before and after the collision detection by the touch sensor 102 occurs.

  FIG. 5 is a side view showing an aspect of a collision between a pedestrian and a vehicle. When the pedestrian 202 collides with the vehicle 204, first, the lower absorber 32B portion of the front bumper 12 contacts the leg of the pedestrian 202, and the lower pressure tube 104 is pressed. However, since a leg part of a human body such as a pedestrian is not fixed to the ground, the leg part leaves the ground immediately after the collision and falls on the hood 206 from the direction of arrow C in FIG. As a result, the pressure on the lower pressure tube 104 is limited, but the upper pressure tube 104 in the upper absorber 32 </ b> A is strongly pressed in the process in which the pedestrian 202 falls on the hood 206.

  FIG. 6 is a side view showing one aspect of the collision between the installation object 208 fixed to the ground such as a roadside marker and the vehicle 204. The installation object 208 such as a roadside marker does not fall on the hood 206 of the vehicle 204 due to a collision with the vehicle 204 like a pedestrian 202, and falls in the direction of arrow D in FIG. Accordingly, although the lower pressure tube 104 is strongly pressed immediately after the collision, the pressure on the upper pressure tube 104 is limited.

  FIG. 7 is a diagram showing a change in output immediately after the collision of the pressure sensor 28A provided in the pressure tube 104 of the present embodiment. FIG. 7A shows a case where a collision with a pedestrian is determined. The case where it does not determine with the collision with a pedestrian is shown. 7A and 7B, pressure sensor output values 70A and 70B are output values of the pressure sensor 28A based on a change in pressure inside the pressure tube 104. The touch sensor detection lines 72A and 72B indicate that the touch sensor 102 is turned on upon detecting a collision, like the touch sensor detection lines 82A and 82B in FIG. 8 and the touch sensor detection lines 92A and 92B in FIG. . Subtracted output values 74A and 74B indicate the result of subtracting the output value of the pressure sensor after the touch sensor 102 is turned on by the output value of the pressure sensor 28A when the touch sensor 102 is turned on. Yes.

  In the present embodiment, when the vehicle collides with a pedestrian or an installation object, the lower pressure tube 104 is first pressed, then the touch sensor 102 is turned on, and the upper pressure tube 104 is pressed. Therefore, the output value of the pressure sensor 28 </ b> A after the touch sensor 102 is turned on includes an output value related to pressing of the lower pressure tube 104 and an output value related to pressing of the upper pressure tube 104. The output value related to the pressing of the upper pressure tube 104 after the touch sensor 102 is turned on is the output value related to the pressing of the lower pressure tube 102 from the output value of the pressure sensor 28A after the touch sensor 102 is turned on. The value is subtracted. In the present embodiment, the output value of the pressure sensor 28A when the touch sensor 102 is turned on when only the lower pressure tube 104 is pressed, and the pressure sensor after the touch sensor 102 is turned on. Are subtracted from each other to calculate subtracted output values 74A and 74B. The subtraction output values 74A and 74B are approximate values of the output value of the pressure sensor 28A related to the pressing of the upper pressure tube 104, or the action related to the pressing of the upper pressure tube 104 is larger than the output value before the subtraction. The reflected output value.

  As described with reference to FIGS. 5 and 6, when the vehicle collides with a pedestrian, the pressure of the lower pressure tube 104 immediately after the collision is limited, but after the touch sensor 102 is turned on. The upper pressure tube 104 is strongly pressed. In the present embodiment, the pressure sensor output value before the touch sensor 102 is turned on is less than the first threshold value a, and the subtracted output value that approximates the output value related to the pressing of the upper pressure tube 104 is the second. It is determined that the vehicle has collided with a pedestrian when the threshold value b is exceeded. The first threshold value a and the second threshold value b are predetermined threshold values, and are specifically determined through a simulation using a computer, a vehicle collision experiment, and the like. In principle, a <b in the present embodiment, but a = b may be used.

  In the case of FIG. 7A, since the pressure sensor output value 70A before the touch sensor 102 is turned on is less than the first threshold value a and the subtraction output value 74A exceeds the second threshold value b, It is determined that the vehicle has collided with a pedestrian. In the case of FIG. 7B, since the pressure sensor output value 70B before the touch sensor 102 is turned on exceeds the first threshold value a, even if the subtraction output value 74B exceeds the second threshold value b. It is not determined that the vehicle has collided with a pedestrian.

  FIG. 8 is a diagram showing an aspect different from FIG. 7 in the change in output immediately after the collision of the pressure sensor 28A provided in the pressure tube 104 of the present embodiment, and FIG. 8A shows a collision with a pedestrian. (B) has shown the case where it is not determined with the collision with a pedestrian.

  In the case of FIG. 8A, the pressure sensor output value 80A before the touch sensor 102 is turned on is less than the first threshold value a, and the subtraction output value 84A exceeds the second threshold value b. It is determined that the vehicle has collided with a pedestrian. In the case of FIG. 8B, the pressure sensor output value 80B before the touch sensor 102 is turned on is less than the first threshold value a, but since the subtraction output value 84B is less than the second threshold value b, the vehicle is a pedestrian. It is not determined that it collided with.

  FIG. 9 is a diagram showing an aspect different from FIGS. 7 and 8 in the change in output immediately after the collision of the pressure sensor 28A provided in the pressure tube 104 of the present embodiment, and (A) is a pedestrian. (B) has shown the case where it does not determine with the collision with a pedestrian.

  FIG. 9 shows a case where the output value of the pressure sensor 28A becomes larger than that in FIGS. 7 and 8 as a result of the vehicle colliding with a heavy pedestrian or a solid installation. ) And FIG. 9B, the pressure sensor output values 90A and 90B before the touch sensor 102 is turned on exceed the first threshold value a, and the subtraction output values 94A and 94B are the first values. The threshold value b of 2 is exceeded. For this reason, in the case of FIG. 9, the presence or absence of the collision with the pedestrian cannot be determined only from the relationship between the first threshold value a and the second threshold value b.

  However, as described above, in a collision with a pedestrian, immediately after the collision, the pedestrian falls on the hood and the upper pressure tube 104 is strongly pressed. Since it falls down, the upper pressure tube 104 is not pressed strongly. In the present embodiment, when the pressure sensor output value before the touch sensor 102 is turned on exceeds the first threshold value a, the subtraction output value is larger than the first threshold value a and the second threshold value b. When the third threshold value c is exceeded, it is determined that the vehicle has collided with a pedestrian.

  In the case of FIG. 9A, since the subtraction output value 94A exceeds the third threshold value c, it is determined that the vehicle has collided with a pedestrian. In the case of FIG. 9B, since the subtraction output value 94B is less than the third threshold value c, it is not determined that the vehicle has collided with a pedestrian.

  In the present embodiment, when the pressure sensor output value before the touch sensor 102 is turned on is less than the first threshold value a, the subtraction output value has collided with the pedestrian when the second threshold value b is exceeded. It is determined. If the pressure sensor output value before the touch sensor 102 is turned on exceeds the first threshold value a, it is determined that the pedestrian collides when the subtracted output value exceeds the third threshold value c. ing.

  In the present embodiment, one pressure tube 104 is disposed in a U-shape lying at the corner of the front bumper 12, and one pressure sensor 28 </ b> A is provided at one end of the pressure tube 104.

  In this embodiment, the pressure sensor output value when the touch sensor 102 is on is calculated from the pressure sensor output value before the touch sensor 102 is turned on and the pressure sensor output value after the touch sensor 102 is turned on. The presence or absence of a collision with a pedestrian is determined from the subtracted output value obtained by subtraction. As described above, the pressure sensor output value before the touch sensor 102 is turned on relates to the pressure on the lower pressure tube 104, and the subtracted output value mainly relates to the pressure on the upper pressure tube 104. It is thought that. Further, in a personal collision, the touch sensor 102 is turned on after the lower part of the front bumper 12 is pressed, and then the upper part of the front bumper 12 is strongly pressed. In the present embodiment, as described above, the first threshold value a and the second threshold value b having a relationship of a ≦ b <c are set between the pressure sensor output value and the subtraction output value before the touch sensor 102 is turned on. And the third threshold value c is applied to determine whether or not there is an interpersonal collision.

  As described above, according to the present embodiment, there is an effect that it is possible to determine the presence or absence of an interpersonal collision at the corner portion of the front bumper 12 with a simple configuration using one pressure tube 104 and one pressure sensor 28A.

  FIG. 10 is a diagram illustrating an example of a flowchart of the interpersonal collision determination of the pedestrian collision detection system 10 according to the first embodiment. The process of FIG. 10 is executed by the ECU 30. First, in step 100, the output value of the pressure sensor 28A is stored immediately after the collision. In step 102, it is determined whether or not the touch sensor 102 is turned on. If the determination is affirmative, a subtraction output value is calculated and stored in step 104.

  In step 106, the first threshold value a, the second threshold value b, and the third threshold value having a relationship of a ≦ b <c between the pressure sensor output value and the subtraction output value before the stored touch sensor 102 is turned on. Applying c, it is determined whether or not there is a personal collision, and the process is terminated.

(Modification of the first embodiment)
FIG. 11 is a diagram illustrating an example of a modification of the first embodiment. In the first embodiment shown in FIG. 4, the chamber main body 22 is provided around the center of the front bumper 12, but in FIG. 11, the touch sensor 112 and the pressure tube 114 are used instead of the chamber main body. Are disposed throughout the vehicle width direction of the front bumper 12.

  In the modification shown in FIG. 11, the touch sensor 112 and the pressure tube 114 are arranged so that the collision with the front bumper 12 detected by the chamber body 22 is closer to the center of the front bumper 12 than in the first embodiment. Detected by a pressure sensor 28C provided in The first threshold value a, the second threshold value b, and the third threshold value c having the relationship of a ≦ b <c are applied to the detected pressure sensor output value and the subtraction output value calculated from the pressure sensor output value. Then, it is determined whether or not there is a person-to-person collision.

  When a collision is detected in the chamber body 22, the collision load is calculated as described above to determine the presence or absence of an interpersonal collision. However, in the modification shown in FIG. 11, it is not necessary to calculate the collision load. Therefore, arithmetic processing can be simplified.

  In the modification shown in FIG. 11, the pressure sensor 28C is provided at one end of the pressure tube 114 and the other end is closed in principle. However, the pressure sensor 28D is also provided at the other end of the pressure tube 114, It may be used as a backup for the sensor 28C.

  FIG. 12 is a diagram illustrating another example of the modification example of the first embodiment. In FIG. 12, a touch sensor 122 </ b> A is provided instead of the chamber main body 22, and the upper pressure tube 124 is disposed near the center of the front bumper 12. Further, the lower pressure tube 124 is disposed at a corner portion of the front bumper 12 as in the first embodiment shown in FIG. 4, and a pressure sensor 28E is provided at the end of the lower pressure tube 124 side. Yes.

  In the modification shown in FIG. 12, the collision at the corner portion of the front bumper 12 is detected by the touch sensor 122B provided at the corner portion, and the collision at the center portion of the front bumper 12 is detected by the touch sensor 122A. As in the first embodiment, the collision at the corner portion has a relationship of a ≦ b <c between the pressure sensor output value before the touch sensor 122B is turned on and the subtraction output value after the touch sensor 122B is turned on. The first threshold value a, the second threshold value b, and the third threshold value c having the above are applied to determine whether or not a personal collision has occurred.

  In the modification shown in FIG. 12, whether or not the collision at the center of the front bumper 12 is an interpersonal collision by calculating a collision load based on the output signal of the pressure sensor 28E provided in the pressure tube 124. Determine.

  FIG. 13 is a diagram illustrating another example of the modification example illustrated in FIG. 11. In FIG. 13, a touch sensor 132 is disposed from the corner portion to the center portion of the front bumper 12 instead of the chamber main body portion 22. Further, a pressure tube 134A is disposed at the upper portion of the front bumper 12, and a pressure tube 134B is disposed at the lower portion thereof from the corner portion of the front bumper 12 to the central portion thereof. At one end, pressure sensors 28F and 28G are provided.

  As shown in the modified example shown in FIG. 11, instead of a single pressure tube in which the upper and lower sides communicate with each other, two independent pressure tubes 134A and 134B are provided on the upper and lower sides. Upper collision and lower collision can be discriminated by the pressure change in each pressure tube. Therefore, unlike the above-described embodiments, it is not necessary to calculate the subtraction output value, and the arithmetic processing related to the determination of the interpersonal collision can be simplified.

  In the modification shown in FIG. 13, the collision at the center of the front bumper 12 is also detected by the touch sensor 132, the pressure sensor 28F provided in the upper pressure tube 134A, and the pressure sensor 28G provided in the lower pressure tube 134B. Detect by. The first threshold value a, the second threshold value b, and the third threshold value c having the relationship of a ≦ b <c are applied to the detected pressure sensor output value and the subtraction output value calculated from the pressure sensor output value. Then, it is determined whether or not there is a person-to-person collision.

  When a collision is detected in the chamber body 22, the collision load is calculated as described above to determine the presence or absence of an interpersonal collision. However, in the modification shown in FIG. 13, it is not necessary to calculate the collision load. Therefore, arithmetic processing can be simplified.

  In the modification shown in FIG. 13, the upper pressure sensor 28F is provided at one end of the upper pressure tube 134A, the lower pressure sensor 28G is provided at one end of the lower pressure tube 134B, and the other end is closed. However, the pressure sensor 28H may be provided at the other end of the upper pressure tube 134A, and the pressure sensor 28I may be provided at the other end of the lower pressure tube 134B. The pressure sensor 28H can be used as a backup for the pressure sensor 28F, and the pressure sensor 28I can be used as a backup for the pressure sensor 28G.

  As described above, according to the present embodiment, it is possible to accurately determine an interpersonal collision from a collision at a corner portion of the bumper 12.

DESCRIPTION OF SYMBOLS 10 Pedestrian collision detection system 14 Bumper reinforcement 20 Pressure sensitive member 26 Pressure chamber 28A, 28B, 28C, 28D, 28E, 28F, 28G, 28H, 28I Pressure sensor (internal pressure detection means)
30 ECU
32A Upper absorber 32B Lower absorber 34 Bumper cover 70A, 70B Pressure sensor output value 72A, 72B Touch sensor detection line 74A, 74B Subtraction output value 80A, 80B Pressure sensor output value 82A, 82B Touch sensor detection line 84A, 84B Subtraction output value 90A , 90B Pressure sensor output value 92A, 92B Touch sensor detection line 94A, 94B Subtraction output value 102, 112, 122B, 122A, 132 Touch sensor (pressure detection means)
104, 114, 124 Pressure tube 134A Upper pressure tube (lower tube)
134B Lower pressure tube (lower tube)
a first threshold value b second threshold value c third threshold value

Claims (5)

A flexible tubular body disposed along the vehicle width direction at a portion including an outer end portion in the vehicle width direction of the upper absorber disposed adjacent to the front surface of the bumper reinforcement disposed with the vehicle width direction as a longitudinal direction. An upper tube,
A lower absorber disposed adjacent to the front surface of the front member disposed below the bumper reinforcement in the vehicle width direction as a longitudinal direction is disposed along the vehicle width direction at a portion including an outer end portion in the vehicle width direction. A lower tube which is a flexible tubular body,
A pressure detecting means that is disposed in a belt shape along the vehicle width direction at a portion including the vehicle width direction outer end portion of the upper absorber, and is turned on or off when pressed;
An internal pressure detecting means for detecting a pressure change inside the upper tube and the lower tube and outputting a signal based on the pressure change;
Pedestrian collision detection system with   The pedestrian collision detection system according to claim 1, wherein the lower tube, the pressure detection unit, and the upper tube are disposed in order from the front of the vehicle.   The walking according to claim 2, further comprising a determination unit that determines the presence or absence of an interpersonal collision by comparing an output value of the internal pressure detection unit before and after the pressure detection unit is turned on or off with a predetermined threshold value. Collision detection system. The predetermined threshold includes a first threshold, a second threshold, and a third threshold, the first threshold is less than or equal to the second threshold, and the second threshold is less than the third threshold Because
The determination means detects the internal pressure after the output value of the internal pressure detection means before the pressure detection means is turned on or off is lower than the first threshold and the pressure detection means is turned on or off. When the output value of the means exceeds the second threshold, or the output value of the internal pressure detection means before the pressure detection means is turned on or off exceeds the first threshold, and the pressure detection means The pedestrian collision detection system according to claim 3, wherein an interpersonal collision is determined when an output value of the internal pressure detection means after being turned on or off exceeds the third threshold value. The upper tube and the lower tube form a single tubular body communicating with each other, and the internal pressure detecting means is provided at one end of the tubular body,
The determination means subtracts the output value of the internal pressure detection means when the pressure detection means is turned on or off from the output value of the internal pressure detection means after the pressure detection means is turned on or off. 5. The pedestrian collision detection system according to claim 4, wherein a subtraction output value is calculated, and the subtraction output value is used as an output value of the internal pressure detection means after the pressure detection means is turned on or off.

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