JP2009234427A - Collision detection device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technology to enable stable collision detection by eliminating influence of dispersion of vehicle speed at the time of collision as much as possible on a collision detection device for a vehicle to detect pressure change of a chamber in a vehicle bumper. <P>SOLUTION: This collision detection device for the vehicle is furnished with a chamber member 7 arranged in the vehicle bumper, a pressure sensor 9 to detect pressure in a chamber space 7a, a vehicle speed sensor 11 and a controller 13. The controller 13 integrates a pressure value detected by the pressure sensor 9 by time and computes a discrimination value of a colliding article by dividing the integrated value by the vehicle speed detected by the vehicle speed sensor. That is, the discrimination value J is computed by an expression J=∫ΔPdt/V when the pressure value in the chamber space is specified as ΔP and the vehicle speed detection value of the vehicle speed sensor is specified as V, and a kind of the colliding article is discriminated as a pedestrian when the discrimination value J is more than a prescribed threshold value or within its range. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle collision detection device, and more particularly to a vehicle collision detection device that determines the type of a collision object based on a pressure change in a vehicle bumper.

  In recent years, for the purpose of protecting pedestrians, in order to protect pedestrians when a collision detection device is attached to the vehicle bumper, the type of collision object is determined at the time of collision with the vehicle, and it is determined that the vehicle is a pedestrian Techniques for operating these devices (for example, active hoods and cowl airbags) have been proposed, and their practical application has been studied.

  That is, when the collision object is not a pedestrian, various adverse effects occur when a protective device on the hood (for example, an active hood) is operated. For example, if it cannot be distinguished from a pedestrian when it collides with a lightweight fallen object such as a triangular cone or a signboard under construction, the protection device is activated wastefully and extra repair costs are generated. In addition, if it is indistinguishable from a pedestrian when it collides with a fixed wall such as a concrete wall or a vehicle, the hood will move backward with the hood lifted, so there is a risk that the hood may enter the passenger compartment and harm the passenger. is there. As described above, it is required to accurately determine the type of the collision object.

  2. Description of the Related Art Conventionally, a vehicle collision detection device has been proposed in which a chamber member is disposed in an absorber portion in a vehicle bumper and a type of a collision object is determined by detecting a pressure change in the chamber space at the time of a collision. (For example, see Patent Documents 1 and 2).

In these vehicle collision detection apparatuses described in Patent Documents 1 and 2, when an object collides with the vehicle bumper, the absorber (chamber member) disposed on the front surface of the bumper reinforcement is deformed in the bumper cover to absorb the impact. Is done. At this time, a pressure change is generated in the chamber due to the deformation of the absorber, and the pressure change is detected by the pressure sensor. And a collision detection apparatus discriminate | determines the kind (particularly whether it is a pedestrian) of a collision object based on the detection result of the pressure change by a pressure sensor. As described above, the type of the collision object is determined with a simple configuration by detecting the pressure change using the structure of the vehicle bumper. Further, even if the deformation amount of the chamber member at the time of the collision is small or regardless of the location of the collision, the collision can be detected with high accuracy.
JP 2007-290682 A JP 2007-290689 A

  As described above, there are many objects that may collide with the bumper while the vehicle is running, such as a pedestrian (person), a concrete cone and other vehicles such as a triangular cone and a signboard under construction. There are kinds of things. Therefore, it is desirable to be able to prevent erroneous detection of the type of collision object due to the influence of noise. In addition, since the degree of impact on the bumper varies depending on the traveling speed of the vehicle, it is necessary to determine the type of the collision object in consideration of the vehicle speed. However, at the time of an actual collision, there is an influence of acceleration / deceleration and ABS, such as a collision while accelerating or decelerating, an ABS device of the vehicle being operated, etc. It is inevitable that it will occur. From this point of view, in a vehicle collision detection device that detects a change in pressure in the chamber with a sensor, it is possible to eliminate the influence of noise and variations in the vehicle speed detection value at the time of collision, and to stably determine the type of collision object Development of technology that enables this is desired.

  The present invention has been made in view of the above problems, and in a vehicle collision detection device that detects a pressure change in a chamber disposed in a vehicle bumper, the influence of noise and variations in the vehicle speed detection value at the time of the collision. It is an object of the present invention to provide a technique capable of discriminating as much as possible and stably determining the type of a collision object.

  Hereinafter, each means suitable for solving the above-described problems will be described with additional effects and the like as necessary.

1. In a vehicle collision detection device configured to detect a collision of an object with a vehicle bumper,
A chamber member disposed in the vehicle bumper and having a chamber space formed therein;
A pressure sensor for detecting the pressure in the chamber space;
A vehicle speed sensor for detecting the vehicle speed of the vehicle;
Integrating means for obtaining a value obtained by integrating the pressure value detected by the pressure sensor with time;
A vehicle collision detection apparatus, comprising: a determination unit that determines the type of a collision object using an integration value obtained by the integration unit and a vehicle speed detected by the vehicle speed sensor.

  According to the means 1, since the value obtained by integrating the pressure value detected by the pressure sensor with time is obtained and discriminated, the influence of noise or the like is reduced as compared with the case where the peak value of the pressure detected by the pressure sensor is obtained and discriminated. It is possible to make a stable determination with less.

  2. The discriminating means calculates the discriminant value J by the equation J = ∫ΔPdt / V, where ΔP is the pressure value in the chamber space and V is the vehicle speed detection value of the vehicle speed sensor. The vehicle collision detection device according to claim 1.

  According to the means 2, the influence of noise or the like can be eliminated and stable detection can be performed, and the vehicle speed detection value V itself is not the square of the vehicle speed detection value V of the vehicle speed sensor by the formula J = ∫ΔPdt / V. Since the integral value is divided (divided) by, the influence of variations in the vehicle speed detection value at the time of collision is reduced, and the type of the colliding object can be determined stably.

  3. 3. The vehicle collision detection device according to claim 1, wherein an absorber is further disposed in the vehicle bumper, and the chamber member is disposed above the absorber. .

  According to the means 3, in the case of a pedestrian, the absorber disposed on the lower side in the vehicle bumper absorbs the impact while damaging the pedestrian while deforming while absorbing the impact, and the chamber member disposed on the upper side Similarly, since the pressure change is detected while absorbing the impact while being deformed, the collision detection accuracy can be improved.

  4). 4. The vehicle collision detection device according to any one of means 1 to 3, wherein the chamber member is made of a soft resin material.

  According to the means 4, since the chamber member is made of a soft resin material, the chamber space is easily distorted due to deformation accompanying shock absorption, and collision detection with a pedestrian can be detected with higher accuracy.

  5). The vehicle collision detection device according to any one of means 1 to 4, wherein the chamber member has a gap communicating with the outside.

  According to the means 5, the deformation of the chamber due to the atmospheric pressure change such as the altitude change can be suppressed.

  Hereinafter, an embodiment in which a vehicle collision detection device of the present invention is embodied will be described in detail with reference to the drawings.

  A vehicle collision detection device according to an embodiment of the present invention is a device configured to detect a collision of an object with a vehicle bumper 1 as shown in FIGS. 1 and a chamber member 7 in which a chamber space 7a is formed, a pressure sensor 9 for detecting the pressure in the chamber space 7a, a vehicle speed sensor 11 for detecting the vehicle speed of the vehicle, and a controller 13. ing. The controller 13 determines the type of the collision object using the integration means for obtaining a value obtained by integrating the pressure value detected by the pressure sensor 9 over time, the integrated value obtained by the integration means, and the vehicle speed detected by the vehicle speed sensor 11. Functions as a means. Thus, in this embodiment, the controller 13 mounted on the vehicle functions as an integrating unit and a determining unit. As shown in FIG. 1B, the controller 13 is connected to the pedestrian protection device 21 and also functions as a controller (control means) of the pedestrian protection device 21. That is, in the example shown in FIG. 1, the vehicle is equipped with a pedestrian protection device 21 such as an active hood or a cowl airbag, and the pedestrian protection device 21 is controlled by a control signal output from the controller 13. The pedestrian protection operation is performed.

  Hereinafter, first, an outline of the entire vehicle bumper and a structure for attaching the pressure sensor 9 to the chamber member 7 will be described.

  FIG. 2 is a cross-sectional view of the main part arranged in the vehicle bumper 1 of the vehicle collision detection device of the present embodiment as viewed from the vehicle width direction. FIG. 3 is a diagram schematically illustrating a state in which the pressure sensor is attached to the chamber member in the vehicle collision detection device of the present embodiment. In FIG. 3, the bumper reinforcement 3 to which the main body having the sensor element of the pressure sensor 7 is fixed is omitted. For convenience of illustration, the orientation and shape of the pressure sensor 9 and the chamber member 7 are different from those in FIG.

  As described above, the vehicle collision detection device according to the present embodiment includes the chamber member 7 disposed in the vehicle bumper 1 and having the chamber space 7a formed therein, and the pressure sensor that detects the pressure in the chamber space 7a. 9 and a pressure introduction pipe 9a (hereinafter also referred to as a pressure receiving portion 9a) as a pressure receiving portion of the pressure sensor 9 from a mounting hole 7h (see FIG. 3) provided in the chamber member 7 to the chamber space 7a. A collision with the vehicle bumper is detected based on the detection result of the pressure sensor 9. In the present embodiment, as shown in FIG. 3, a gap S is provided at least between the mounting hole 7 h of the chamber member 7 and the pressure receiving portion 9 a of the pressure sensor 9.

  As shown in FIG. 2, a bumper reinforcement 3, a chamber member 7, and an absorber 4 are provided in the vehicle bumper 1 (the vehicle rear side of the bumper cover 2). The chamber member 7 and the absorber 4 are disposed on the vehicle front side of the bumper reinforcement 3, and the absorber 4 is disposed adjacent to the lower portion of the chamber member 7. A front side member 5 of the vehicle is adjacent to the bumper reinforcement 3 on the vehicle rear side.

  The chamber member 7 is disposed in the vehicle bumper 1 on the vehicle front side of the bumper reinforcement 3, and a chamber space 7 a is formed in the main body portion 7 </ b> A having a shape substantially along the bumper reinforcement 3. . The chamber member 7 is integrally formed as a whole by blow molding using a soft resin material (for example, low density polyethylene).

  The bumper reinforcement 3 is a substantially band-shaped metal frame having a surface facing the bumper cover 2, and is fixed to the front side member 5 of the vehicle along the width direction of the vehicle. As shown in FIG. 2, the bumper reinforcement 3 has an eye-shaped cross-sectional structure in which a beam is provided.

  The absorber 4 is fixed to the lower side of the bumper reinforcement 3, and the surface facing the inner wall surface of the bumper cover 2 is formed in a curved shape that is curved along the inner peripheral surface of the bumper cover 2 (in the drawing). Is abbreviated to a rectangular cross section). The absorber 4 is generally formed of foamed resin in order to absorb the impact caused by the collision by its own deformation.

  The pressure sensor 9 is, for example, a known sensor capable of detecting a change in gas pressure, and includes a pressure introduction pipe 9a as a pressure receiving part that introduces pressure into the sensor element. The main body of the pressure sensor 9 having a sensor element is fixed in the bumper reinforcement 3, and the distal end side of the pressure introduction pipe (pressure receiving portion) 9 a is inserted into the chamber space 7 a of the chamber member 7.

  The chamber member 7 disposed on the vehicle front side of the bumper reinforcement 3 transmits the deformation of the chamber member 7 due to the impact of the collision to the pressure sensor 9 as the pressure fluctuation accompanying the distortion of the chamber space 7a provided therein. The pressure sensor 9 detects the pressure fluctuation of the air introduced from the chamber space 7a via the pressure receiving portion 9a inserted into the chamber space 7a and transmits it to the controller 13. That is, the pressure sensor 9 is electrically connected to the controller 13 via the transmission line 9a, and outputs a signal proportional to the detected pressure to the controller 13.

  The vehicle speed sensor 11 is a known speed sensor that can detect the traveling speed of the vehicle, and is electrically connected to the controller 13 via the transmission line 11a. In this embodiment, a wheel speed sensor is used.

  The controller 13 is an electronic control device for performing deployment control of the above-described cowl airbag or the like when the type of the collision object is determined to be a pedestrian, and signals output from the pressure sensor 9 and the vehicle speed sensor 11 are transmitted. It is configured to be input via lines 9a and 11a, respectively. As described above, the controller 13 integrates the pressure value detected by the pressure sensor 9 over time, and executes a process of determining the type of the collision object using the integrated value and the vehicle speed detected by the vehicle speed sensor 11. The controller 13 outputs a control signal for operating the pedestrian protection device 21 when the type of the collision object is determined to be a pedestrian. The pedestrian protection device 21 performs the pedestrian protection operation according to the control signal output from the controller 13. Specifically, the active hood is activated or the cowl airbag is deployed on the windshield of the vehicle.

  As described above, the chamber member 7 has a chamber space 7a formed inside the main body 7A, and air is sealed in the chamber space 7a. In the default state, it is ideal that the air in the chamber space 7a is maintained at the same pressure as the atmospheric pressure to suppress the deformation of the chamber due to the atmospheric pressure change such as the altitude change. The gap S communicates with the outside.

  Here, as described above, since the pressure receiving portion 9a of the pressure sensor 9 is inserted into the chamber space 7a from the mounting hole 7h of the chamber member 7, the vehicle collision detection device of this embodiment is shown in FIG. As described above, a gap S is provided between the inserted pressure receiving portion 9a and the mounting hole 7h. Thereby, atmospheric pressure and the pressure in the chamber space 7a can be made equal. Further, a structural effect that the assembly of the pressure sensor 9 to the chamber member 7 is facilitated can be obtained.

  Next, in the vehicle collision detection apparatus of the present embodiment, a process for determining the type of the collision object when an object collides with the vehicle bumper 1 will be described.

  When the collision of the object with the vehicle bumper 1 occurs, the chamber member 7 at the collision portion is crushed, and the gas pressure in the chamber space 7a increases (that is, changes). A change in gas pressure in the chamber space 7a is detected by the pressure sensor 9. The controller 13 takes in a signal output from the pressure sensor 9 through the transmission line 9a and takes in a vehicle speed signal from the vehicle speed sensor 11 through the transmission line 11a. The controller 13 obtains a value obtained by integrating the pressure value detected by the pressure sensor 9 with time, and calculates the discriminant discrimination value by dividing the integrated value by the vehicle speed detection value from the vehicle speed sensor 11. Whether or not the colliding object is a pedestrian or the like is determined based on whether or not the value is within a predetermined threshold.

  By the way, since the mass differs between the human body and the other collision object, the maximum value (peak value) of the output of the pressure sensor 9 is different. Therefore, it is possible to classify the type of the collision object from the maximum value (peak value) of the output of the pressure sensor 9. However, since it is impossible to eliminate the influence of noise or the like, it is difficult to accurately detect the maximum value (peak value) of the output of the pressure sensor 9. Therefore, in the vehicle collision detection device of the present embodiment, the type of the collision object is discriminated using the integrated value instead of the maximum value (peak value) of the output of the pressure sensor 9. However, the output of the pressure sensor 9 (in other words, the amount of deformation of the chamber member 7) depends on the energy of impact caused by a collision with a certain mass at a certain speed. Determine.

  Hereinafter, the collision detection method in this embodiment will be described in detail. In the vehicle collision detection apparatus of the present embodiment, the controller 13 shown in FIG. 1B functions as the integration unit and the determination unit described above. At this time, the controller 13 calculates the discriminant value J by the equation J = ∫ΔPdt / V, where ΔP is the pressure value in the chamber space and V is the vehicle speed detection value of the vehicle speed sensor.

  That is, when the present inventor obtains a value obtained by integrating the pressure value detected by the pressure sensor 9 with time, it becomes possible to reduce the influence of noise and the like and to detect a stable collision, and to take into account the speed variation described above. Theoretically, it was found that by dividing by the collision speed itself instead of the square of the collision speed, the influence of the speed variation is reduced and stable collision detection becomes possible.

  Hereinafter, with reference to FIGS. 4A and 4B, a determination method for integrating the pressure value with time will be described in an easy-to-understand manner.

  First, as shown in FIG. 4A, when a collision object of a certain mass M collides with the vehicle bumper 1 at a collision speed (vehicle speed detection value by a vehicle speed sensor) V, the vehicle bumper 1 is only ΔS by the collision load F. As a result, the chamber member 7 is crushed and the volume of the chamber space 7a changes by ΔV, so that the pressure sensor 9 detects the pressure change ΔP. In FIG. 4A, the illustration of the absorber 4 is omitted for convenience of explanation.

On the other hand, the value obtained by integrating the pressure change ΔP with time, that is, the relationship between the pressure change ΔP and time [t] is as shown in the graph of FIG. 4B, and the area of the hatched portion in the graph of FIG. Corresponds to the integral value. That is, by integrating the pressure change ΔP with respect to time [t],
[Equation 1] ∫ΔPdt -------- (1)
It is represented by

As described above, the output of the pressure sensor 9 (in other words, the amount of deformation of the chamber member 7) is determined by taking into account the vehicle speed at the time of the collision because it depends on the energy of the impact caused by the collision of the collision object at a certain speed. Therefore, by dividing the above integrated value ∫ΔPdt by the vehicle speed detection value at the time of collision by V, the discriminant value J is given by [Equation 2] J = ∫ΔPdt / V --------- -It can be obtained by (2).

    As described above, the value ∫ΔPdt obtained by integrating the pressure value detected by the pressure sensor 9 with time is obtained, and the integrated value ∫ΔPdt is divided by the vehicle speed detection value V at the time of collision, thereby determining the discriminant value J = ∫ΔPdt / V can be calculated.

  Thus, when the pressure value in the chamber space 7a detected by the pressure sensor 9 is ΔP and the vehicle speed detection value of the vehicle speed sensor 11 is V, the discriminant value J is calculated by the equation J = ∫ΔPdt / V. As a result, variations in the vehicle speed detection value are reduced, and stable collision detection is possible.

In the present embodiment, a value ∫ΔPdt obtained by integrating the pressure value detected by the pressure sensor 9 over time is obtained, and the integrated value ∫ΔPdt is divided by (divided), in particular, the vehicle speed detection value V at the time of collision. It is characterized in that J is calculated. That is, since the variation in the vehicle speed detection value V itself at the time of the collision is inevitably present, for example, if it is divided (divided) by the square of the collision speed [V ² ], the influence of the variation is also squared. The vehicle speed at the time of collision is also taken into consideration while preventing it.

  In order to verify the effectiveness of the above discriminating method, the present inventor prepared a 7.7 kg impactor and a roadside marker as shown in FIG. 5 (a) as examples of pedestrians and other items. Experiments were performed in which the first and second collisions were performed twice. The speed shown in the upper right of the graph of FIG. 5A represents the vehicle speed detection value at the time of the first and second collisions of the 7.7 kg impactor and the roadside marker, respectively.

  As shown in FIG. 5A, a 7.7 kg impactor (corresponding to a pedestrian) and a roadside marker (corresponding to other than a pedestrian) have different ways of changing pressure with time, and their maximum values (peak values) are also different. As shown in FIG. 5A, even if the speed slightly changes between the first time and the second time, the maximum value (peak value) varies. However, these pressure values shown in FIG. 5A are included in the above-described equation J = ∫ΔPdt / V to obtain the discriminant value J, and the relationship with time is shown in a graph. As shown, it was found that both the 7.7 kg impactor and the roadside marker reached a stable value, for example, 20 milliseconds after the collision, and the stable value continued thereafter.

  Thus, a value ∫ΔPdt obtained by integrating the pressure value detected by the pressure sensor 9 with time, which is the determination method of the present embodiment, is obtained, and this integrated value ∫ΔPdt is divided by the vehicle speed detection value V at the time of collision (divide). Thus, the effectiveness of calculating the discriminant value J was verified.

  Next, the process flow of the controller 13 in the vehicle collision detection device will be described. FIG. 6 is a flowchart showing the processing of the controller 13. The controller 13 stores in advance a collision detection program in a memory (not shown) or the like, and a CPU (not shown) executes each process described below according to the program.

  As shown in FIG. 6, the controller 13 performs a process of initializing a calculation value (an initial value setting process such as an initial value of each sensor) as an initial process (step S-1).

  Subsequently, the controller 13 reads the vehicle speed detection value V detected by the vehicle speed sensor 11 (step S-2), and determines whether or not the vehicle speed detection value V is within a predetermined threshold value (minimum value and maximum value). Judgment is made (step S-3). This is because the speed at which the pedestrian protection function such as the above-described pedestrian protection device acts effectively is determined by the vehicle shape and the like, so that the collision is detected only when the speed is within such a range. is there. When the vehicle speed detection value V is within a predetermined threshold (minimum value and maximum value) (Yes in step S-3), the pressure detection value P [t] detected by the pressure sensor 9 is read (step S). -4). And the controller 13 performs the process which integrates the pressure detection value P about time [t] as an integration means mentioned above (step S-5), for example, the detection value of the pressure sensor 9 is default. The process is performed until the value reaches a value (for example, 0 [kPa]) (Yes in Step S-6), and an integrated value of the pressure detection value P is obtained (Step S-7). Subsequently, the controller 13 calculates the discrimination value J of the colliding object from the obtained integral value using the formula J = ∫ΔPdt / V as the discrimination means described above (step S-8). Furthermore, the controller 13 determines whether the calculated discriminant value J is equal to or greater than a predetermined threshold as a discriminating unit (step S-9), and if it is equal to or greater than the threshold (Yes in step S-9), It is detected that the vehicle has collided with the pedestrian, that is, the type of the collision object is determined to be a pedestrian (step S-10). On the other hand, if it is not equal to or greater than the threshold (No in step S-9), it is detected that the vehicle collides with a person other than a pedestrian, that is, the type of colliding object is determined as an object other than a pedestrian (step S-11). Here, when the threshold value for discriminating the pedestrian of the discriminant value J is less than 5 [kPa / (km / h)], for example, it is discriminated as an object other than the pedestrian. Unlike the case of step S-9 shown in the figure, for example, in the case of 25 [kPa / (km / h)] or more, it may be determined as an object other than a pedestrian. Or, unlike the case of step S-9 in the figure, if it is within a predetermined range, for example, within a range of 5 [kPa / (km / h)] to 25 [kPa / (km / h)], a pedestrian [See also FIG. 5 (b)].

  As is apparent from the above description, according to the present embodiment, when a collision object collides with the vehicle bumper 1, the chamber member 7 disposed on the front surface of the bumper reinforcement 3 is deformed in the bumper cover 2. The shock is absorbed by. At this time, a pressure change occurs in the chamber space 7 a due to the deformation of the chamber member 7, and the pressure change is detected by the pressure sensor 9. Then, the controller 13 obtains a value obtained by integrating the pressure value detected by the pressure sensor 9 with time, and uses the obtained integrated value and the vehicle speed detected by the vehicle speed sensor 11 to obtain a discrimination value for discriminating the type of the collision object. It is possible to stably determine whether or not the collision object is a pedestrian depending on whether or not the calculated determination value is within a predetermined threshold. That is, according to the present embodiment, it is possible to accurately determine the type of the collision object with a simple configuration by detecting the pressure change using the structure of the vehicle bumper 1.

  Further, according to the present embodiment, it is possible to determine the type of the collision object in consideration of the vehicle speed at the time of the collision detected by the vehicle speed sensor, so that the collision detection with higher accuracy can be performed. Further, a value obtained by integrating the pressure value detected by the pressure sensor 9 with respect to time is obtained, and the obtained integrated value is divided (divided) by the vehicle speed detected by the vehicle speed sensor 11, thereby calculating the discrimination value of the colliding object and causing the collision. Since the type of the object is discriminated, the influence of the speed variation is reduced, and the type of the colliding object can be discriminated stably.

  In addition, this invention is not limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the main point of this invention. For example, in the above-described embodiment, an example is shown in which an absorber separate from the chamber member is disposed in the vehicle bumper, and the chamber member is disposed above the absorber. However, the chamber member also serves as the absorber. Also good. Moreover, although the example in which the chamber member is comprised from the soft resin material was shown, of course, the chamber member may be comprised from another material. Further, although the chamber member has a gap communicating with the outside, the gap need not be provided.

  The present invention can be applied to a vehicle collision detection device that can identify a collision object based on a pressure change in a vehicle bumper.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the collision detection apparatus for vehicles which concerns on embodiment of this invention, (a) is a figure which shows the structure with the schematic longitudinal cross-section of a vehicle bumper, (b) is the functional block diagram. . It is sectional drawing which looked at the principal part of the collision detection apparatus for vehicles of the embodiment of the present invention arranged in the vehicle bumper from the vehicle width direction. It is a figure which shows the outline of the state which attached the pressure sensor to the chamber member in the collision detection apparatus for vehicles of embodiment of this invention. (A) is a conceptual diagram for demonstrating the method of calculating the discriminant value by integrating the detected value (pressure value) of a pressure sensor in embodiment of this invention, (b) is the pressure change in chamber space, and It is a graph which shows the relationship with time. It is a figure for demonstrating the relationship between the discriminating value which detects the pressure change in a chamber space, and a collision in embodiment of this invention, (a) shows the conditions of the collision experiment to a vehicle bumper simply, A graph showing the relationship between the pressure in the space and the time, (b) is the integration of the pressure value in the chamber space obtained by the collision experiment, and the discriminant value obtained by dividing the integrated value by the vehicle speed and the time It is a graph which shows a relationship. It is a flowchart which shows the process of the controller in the collision detection apparatus for vehicles which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle bumper 2 Bumper cover 3 Bumper reinforcement 7 Chamber member 7a Chamber space 9 Pressure sensor 11 Vehicle speed sensor 13 Controller (integration means, discrimination means)

Claims (5)

In a vehicle collision detection device configured to detect a collision of an object with a vehicle bumper,
A chamber member disposed in the vehicle bumper and having a chamber space formed therein;
A pressure sensor for detecting the pressure in the chamber space;
A vehicle speed sensor for detecting the vehicle speed of the vehicle;
Integrating means for obtaining a value obtained by integrating the pressure value detected by the pressure sensor with time;
A vehicle collision detection apparatus, comprising: a determination unit that determines the type of a collision object using an integration value obtained by the integration unit and a vehicle speed detected by the vehicle speed sensor.   The discriminating value is calculated by the equation J = ∫ΔPdt / V, where the discriminating means has a pressure value in the chamber space as ΔP and a vehicle speed detection value of the vehicle speed sensor as V. The vehicle collision detection device according to claim 1.   3. The vehicle collision detection according to claim 1, wherein an absorber is further disposed in the vehicle bumper, and the chamber member is disposed above the absorber. 4. apparatus.   4. The vehicle collision detection device according to claim 1, wherein the chamber member is made of a soft resin material. 5.   5. The vehicle collision detection device according to claim 1, wherein the chamber member has a gap communicating with the outside. 6.

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