JP5803852B2 - Collision detection device and occupant protection system - Google Patents

Description

  The present invention relates to a collision detection device and an occupant protection system for protecting an occupant on a vehicle.

  Conventionally, a vehicle includes a collision detection device that detects a collision of the own vehicle or a collision with the own vehicle, and an occupant that can protect an occupant in the passenger compartment when the own vehicle collides or is collided with the own vehicle. An occupant protection system including a protection device is mounted. As such an occupant protection device, a so-called airbag that is deployed in the event of a collision is known. For example, in Patent Document 1 below, a determination that an airbag deployment based on pressure detected by a pressure sensor is “performs deployment”, and an airbag deployment determination based on acceleration detected by an acceleration sensor is “deployment”. In the case of the determination “to perform”, a technique for determining “to deploy the airbag” is disclosed. The pressure sensor is a sensor that detects a pressure in a region sealed by an outer panel and an inner panel in a door on the side surface of the vehicle. On the other hand, the acceleration sensor is a sensor that is provided at a position in the passenger compartment and detects acceleration applied to the occupant due to a collision.

JP 2008-080979 A

  By the way, in the above conventional technology, since it is determined whether or not the vehicle is a collision according to the pressure in the door and the acceleration applied to the occupant, depending on the magnitude of the pressure and acceleration, depending on the occupant, the airbag There is a possibility that it is determined that there is a collision even when it is felt that there is a low necessity for deploying. When it is felt that the need to deploy an airbag is low, when the door is hit with a bat, when the ball hits the door, when a bicycle or a person collides, This includes not only the case where the collision does not occur, but also the case where a minor collision such that some passengers feel that the airbag is not deployed. As described above, conventionally, even when it is felt that it is not necessary to determine that a collision has occurred depending on the occupant, it may be determined that a collision has occurred and the occupant may feel uncomfortable.

  Therefore, an object of the present invention is to provide a collision detection device and an occupant protection system that improve the inconveniences of the conventional example and improve the collision determination accuracy.

In order to achieve the above object, the present invention provides a pressure detection unit that detects a pressure in a space configured close to the inside of a vehicle exterior member, a speed change amount detection unit that detects a speed change amount of a vehicle body, A collision occurs when it is determined that a collision has occurred based on the acceleration detection unit that detects the acceleration of the vehicle body and the amount of change in the pressure per unit time, and it is determined that a collision has occurred based on the acceleration. When it is determined that a collision has occurred based on the amount of change in the pressure per unit time, and a collision has occurred based on the amount of change in speed. A second collision determination unit that performs a final determination that a collision has occurred, and the second collision determination unit generates a collision when the amount of change in pressure per unit time is smaller than that of the first collision determination unit. The first collision determination unit It characterized by determining that a collision has occurred if at least one collision of preliminary second collision determination unit is finally determined to have occurred.

  Further, the collision determination based on the amount of change in pressure per unit time by the first collision determination unit, the collision determination based on the acceleration by the first collision determination unit, and the unit by the second collision determination unit It is desirable that the collision determination based on the pressure change amount per time and the collision determination based on the speed change amount by the second collision determination unit are executed in parallel.

In order to achieve the above object, the present invention provides a pressure detection unit that detects a pressure in a space formed close to the inside of an exterior member of a vehicle, and a speed change amount detection unit that detects a speed change amount of a vehicle body. And an acceleration detection unit that detects the acceleration of the vehicle body, a collision is determined based on the amount of change in the pressure per unit time, and a collision is determined based on the acceleration. When it is determined that a collision has occurred based on the amount of change in the pressure per unit time and a collision has occurred based on the amount of change in speed A second collision determination unit that performs final determination that a collision has occurred, an occupant protection device that protects an occupant in the passenger compartment, and an occupant protection control that operates the occupant protection device when it is finally determined that a collision has occurred comprising a part, the said The second collision determination unit determines that a collision has occurred when the amount of change in pressure per unit time is smaller than that of the first collision determination unit, and includes a first collision determination unit and a second collision determination unit. If it is finally determined that the collision least one occurs, it characterized Rukoto to operate the occupant protection device.

  The collision detection device and occupant protection system according to the present invention determines that a collision has occurred based on the amount of change in pressure per unit time in space and determines that a collision has occurred based on the amount of change in vehicle speed Finally, a final determination is made that a collision has occurred. Here, by determining each of the collisions, it is possible to determine that a collision that requires quick activation of the occupant protection device or a collision at a highly rigid portion of the vehicle is a collision that requires operation of the occupant protection device. On the other hand, when the operation of the occupant protection device such as a minor collision is not required, it can be determined that the collision does not require the operation of the occupant protection device. Therefore, this collision detection device and occupant protection system can improve collision determination accuracy.

FIG. 1 is a diagram illustrating an example of a configuration of a collision detection device and an occupant protection system according to the present invention. FIG. 2 is a diagram for explaining the arrangement of the pressure sensors. FIG. 3 is a diagram illustrating an example of the relationship between the pressure in the space and the pressure gradient when an external force is applied. FIG. 4 is a diagram for explaining a side collision test. FIG. 5 is a diagram illustrating an example of a collision determination map based on pressure and pressure gradient. FIG. 6 is a diagram illustrating an example of a collision determination map based on lateral acceleration. FIG. 7 is a diagram illustrating an example of a collision determination map based on pressure and pressure gradient. FIG. 8 is a diagram illustrating an example of a collision determination map based on a speed change amount. FIG. 9 is a flowchart for explaining operations of the collision detection device and the occupant protection system.

  Embodiments of a collision detection device and an occupant protection system according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited to the embodiments.

[Example]
An embodiment of a collision detection device and an occupant protection system according to the present invention will be described with reference to FIGS.

  Reference numeral 1 in FIG. 1 indicates an occupant protection system of the present embodiment. The occupant protection system 1 is operated by an electronic control unit (ECU) 10 and includes an occupant protection device 20 that protects an occupant in a vehicle compartment when the host vehicle collides with or collides with the host vehicle. Yes. The occupant protection device 20 is equipped with a so-called airbag that protects the occupant by deploying in the event of a collision.

  Here, the occupant protection device 20 is operated by the occupant protection control unit of the electronic control device 10 when a collision is detected. Accordingly, the occupant protection system 1 is provided with a collision detection device that detects a collision of the own vehicle or a collision with the own vehicle. In this example, the electronic control device 10 is provided with the arithmetic processing function of the collision detection device. Below, this collision detection apparatus is explained in full detail.

  This collision detection device has a pressure change amount per unit time (hereinafter referred to as “pressure gradient”) ΔP (t) and a vehicle body acceleration G ( Based on the lateral acceleration Gy and the longitudinal acceleration Ga), it is determined whether or not the collision requires an operation of the occupant protection device 20.

  The space is provided in at least one of the side surface, front surface or rear surface of the vehicle body. Accordingly, the exterior member refers to a vehicle outer panel or cowl, such as a door panel or front and rear bumpers. In addition, this space is a space where the internal pressure changes when a force such as impact is applied from the outside or when a sudden change in atmospheric pressure occurs outside, not only a highly airtight sealed space. In addition, a space having a gap, an opening, or the like is included, although it is closed to such an extent that a change in the internal pressure appears even when an external force is applied. The term “proximity” as used herein indicates that there is a space immediately inside the exterior member. Specifically, it shows that there is a space at least inside the vehicle with respect to the exterior member and outside the vehicle with respect to members (door trim, dash panel, etc.) constituting the cabin (so-called cabin). Therefore, the space consists of members constituting the door (for example, door outer and door inner), members constituting the bumper (for example, bumper absorber and bumper force), and the like. For example, the space is a collision location that induces the operation of the occupant protection device 20 and is preferably provided in a portion adjacent to the collision location or in the vicinity of the collision location.

  More specifically, this collision detection device performs a collision determination based on the pressure gradient ΔP (t) and a collision determination based on the acceleration G of the vehicle body, and it is determined that a collision has occurred in each collision determination. Finally, a final determination is made that a collision requiring the operation of the occupant protection device 20 has occurred. On the other hand, if it is not determined that a collision has occurred in one of the two collision determinations, it is not determined that a collision requiring the operation of the occupant protection device 20 has occurred. Each of the collision determinations may be executed first, or may be executed in parallel.

  First, collision determination based on the pressure gradient ΔP (t) will be described.

  Here, the collision detection apparatus will be described with reference to detection of a side collision (hereinafter referred to as “side collision”). The door 100 on the side surface of the vehicle is covered with an outer panel 102 having an inner panel 101 as an outer plate, and includes the above-described space S formed by the inner panel 101 and the outer panel 102. A pressure sensor (pressure detector) 31 for detecting the pressure P (t) in the space S is attached to the door 100 (FIGS. 1 and 2). In this example, the pressure sensor 31 is attached to the outer panel 102 side of the inner panel 101, that is, in the space S. However, if the detection unit is disposed in the space S, the pressure sensor 31 may be the inner panel 101. A main body portion may be attached to the door trim 103 side. In one vehicle, at least one pressure sensor 31 is disposed on each of the left and right doors 100. Further, when a plurality of doors 100 are present on one side surface of the vehicle, the pressure sensor 31 may be provided on each door 100. A detection signal of the pressure sensor 31 is transmitted to the electronic control device 10. In the electronic control unit 10, the pressure gradient ΔP (t) is calculated based on the detection signal.

  When the outer panel 102 is recessed due to an external force, the pressure P (t) increases in the space S as the volume decreases. Also, when the wheel is pushed by an external force from the front or rear of the vehicle and the wheel pushes the member covering the tire house toward the door 100, the pressure in the space S decreases with the pressure P (t ) May increase. For this reason, when the pressure P (t) in the space S exceeds a predetermined threshold, it can be estimated that a collision requiring the operation of the occupant protection device 20 has occurred. However, if the necessity of operation of the occupant protection device 20 is determined only by the magnitude of the pressure P (t), there is no collision that requires the operation of the occupant protection device 20 (the above-mentioned bicycle or person has collided). However, when the pressure P (t) in the space S exceeds a predetermined threshold value, it is erroneously determined that a collision requiring the operation of the occupant protection device 20 has occurred.

  Here, the pressure P (t) and the pressure gradient ΔP (t) in the space S when an impact force that does not require the operation of the occupant protection device 20 is applied to the door 100 and the operation of the occupant protection device 20 are required. The pressure P (t) and the pressure gradient ΔP (t) in the space S when the impact force is applied to the door 100 are compared (FIG. 3).

  In FIG. 3, a curve indicated by a one-dot chain line, a two-dot chain line, or a broken line is an example when an impact force that does not require the operation of the occupant protection device 20 is applied to the door 100, that is, when it should be determined that there is no collision. The curve indicated by the alternate long and short dash line is, for example, when a bicycle or a person collides, that is, the contact area to which an impact force is applied is large (deformation is large) and the deformation speed is small. ) Shows a form when the pressure gradient ΔP (t) in the space S becomes small, although it becomes larger. This curve is obtained by a mean evaluation test along such a case. Further, the curve indicated by the broken line indicates that the pressure gradient ΔP (t (t) in the space S is obtained when the door 100 is hit with the bat or when the ball hits the door 100, that is, the deformation is local and the deformation speed increases. ) Shows a form when the pressure P (t) in the space S becomes small, although it becomes larger. This curve is obtained by a mean evaluation test along such a case.

  On the other hand, the curve indicated by the solid line in FIG. 3 has a portion where the pressure gradient ΔP (t) of the space S with respect to the pressure P (t) of the space S is larger than the curve indicated by the alternate long and short dash line. Further, the curve indicated by the solid line has a portion where the pressure P (t) in the space S with respect to the pressure gradient ΔP (t) in the space S is larger than the curve indicated by the broken line. The curve shown by the solid line is an example when an impact force that requires the operation of the occupant protection device 20 is applied to the door 100, that is, when it is determined that the collision is occurring. This curve is obtained from the test result of the side collision test using the cart 200 of FIG. The side collision test may use test conditions (such as the speed at the time of collision of the carriage 200) equivalent to the side collision test stipulated by laws and regulations.

  This collision detection device executes a collision determination based on the pressure gradient ΔP (t) using a collision determination map created based on the test results of the above-described mean evaluation test and the side collision test. The collision determination map is prepared in advance in the vehicle based on the test result.

  An example of the collision determination map is shown in FIG. In the collision determination map of FIG. 5, one region is defined as a region where it is not determined that a collision requiring the operation of the occupant protection device 20 has occurred (hereinafter referred to as a “collision determination failure region”). The other area is an area where it is determined that a collision requiring the operation of the occupant protection device 20 has occurred (hereinafter referred to as a “collision determination failure area”). In this collision determination map, regardless of the magnitude of the pressure gradient ΔP (t) in the space S, a collision occurs in a region below a predetermined threshold value (pressure element of the determination threshold value) P1 at which the pressure P (t) in the space S is minimized. This is a determination failure area. In this collision determination map, if the pressure P (t) is higher than the threshold value P1, a pressure gradient that is equal to or lower than the threshold value ΔP1 with a predetermined pressure gradient threshold value (pressure gradient element of the determination threshold value) ΔP1 as a boundary. The region of ΔP (t) is set as the collision determination failure region, and the region of the pressure gradient ΔP (t) exceeding the threshold value ΔP1 is set as the collision determination determination region.

  The threshold value ΔP1 of the pressure gradient is for avoiding erroneous determination as a collision when no collision occurs. For example, the pressure gradient ΔP (t) in the above test result when no collision occurs. The maximum value or a value that is larger than the maximum value by the correction amount is used. The correction amount is, for example, a detection error or calculation error when obtaining the above test result, a detection error or calculation error of the pressure P (t) and the pressure gradient ΔP (t) in the space S when performing the collision determination. It is meant to make up.

  When an impact force is applied to the door 100, the collision detection device establishes a collision determination even if a part of a curve composed of a set of the pressure P (t) and the pressure gradient ΔP (t) in the space S detected and calculated at that time is satisfied. If it is in the area, it is determined that a collision requiring the operation of the occupant protection device 20 has occurred, and if the curve formed by the set is not in the collision determination establishment region, a collision requiring the operation of the occupant protection device 20 has occurred. Judge that there is no. That is, the collision detection device compares the pressure P (t) and the pressure gradient ΔP (t) with the determination threshold value including the pressure threshold value P1 and the pressure gradient threshold value ΔP1, thereby comparing the impact force Is a collision that requires operation of the occupant protection device 20.

  In this exemplary collision determination map, a region of the minimum pressure P (t) that is difficult to be detected by the pressure sensor 31 (region of P1 or less) is set as a collision determination failure region. For this reason, when an impact force is applied to the door 100, the exemplary collision detection device includes the pressure gradient threshold value ΔP1 corresponding to the detected pressure P (t) and the calculated pressure gradient ΔP (t). By making the comparison, it may be determined whether or not the impact force is a collision that requires the operation of the occupant protection device 20. If the pressure gradient ΔP (t) is greater than the threshold value ΔP1, the collision detection device determines that a collision requiring the operation of the occupant protection device 20 has occurred. If the pressure gradient ΔP (t) is equal to or less than the threshold value ΔP1, It is determined that a collision requiring the operation of the occupant protection device 20 has not occurred.

  Next, collision determination based on the acceleration G of the vehicle body will be described.

  The acceleration sensor (acceleration detection unit) 32 is disposed in a place that is difficult to be deformed by a collision, for example, a floor panel, a floor tunnel, a housing of the electronic control device 10, or the like. The hard-to-deform portion is an acceleration component accompanying the deformation even if some deformation occurs in the part when an external force such as impact (when a ball hits later) hits or a collision is applied to the vehicle body. It is a part on the part which is not generated (that is, a part where an acceleration component accompanying deformation is not output from the acceleration sensor 32), and includes a part which is not deformed at that time. More specifically, the hard-to-deform portion is a portion where an acceleration change due to a collision occurs, but an acceleration change due to an impact does not occur or an acceleration change due to the impact is difficult to occur. Therefore, from the acceleration sensor 32 arranged here, a greater change in acceleration is detected when a collision occurs than when an impact is applied. Since the acceleration sensor 32 determines a side collision, the acceleration sensor 32 detects the lateral acceleration Gy of the vehicle body. If an acceleration sensor for lateral acceleration detection used for vehicle behavior stabilization control or the like already exists, this acceleration sensor can be used if the acceleration sensor is arranged at a location that is difficult to deform due to a side collision. The detection signal of the sensor may be used.

  A detection signal of the acceleration sensor 32 is also transmitted to the electronic control device 10. In the electronic control device 10, the lateral acceleration Gy based on the detection signal is compared with a predetermined threshold value Gy0, and when the lateral acceleration Gy is larger than the threshold value Gy0, a collision requiring the operation of the occupant protection device 20 has occurred. A determination is made (FIG. 6). The threshold value Gy0 is, for example, a value larger than the maximum value by the maximum value or correction amount of the lateral acceleration Gy in the test result described above when no collision has occurred. The correction amount is, for example, for compensating for a detection error or calculation error when obtaining the test result, or a detection error or calculation error of the lateral acceleration Gy when performing the collision determination.

  Whether or not the collision requiring the operation of the occupant protection device 20 has occurred by executing the collision determination based on the pressure gradient ΔP (t) and the collision determination based on the acceleration G of the vehicle body, respectively. Make a final decision on whether or not. However, in the collision determination based on the pressure gradient ΔP (t), the outer panel 102 has a dent that only reduces the volume of the space S (that is, changes the pressure P (t) of the space S). If the pressure gradient ΔP (t) of S does not increase until it exceeds the threshold value ΔP1, it is not possible to determine that the collision requires the operation of the occupant protection device 20. For this reason, even if a collision that actually requires the operation of the occupant protection device 20 occurs, it may not be determined that a collision that requires the operation of the occupant protection device 20 has occurred if the collision location is a highly rigid part of the vehicle body. There is. The high-rigidity part is a predetermined part of the vehicle body that hardly changes the pressure P (t) in the space S even when an external force is applied, or at which the detected pressure P (t) is minimized. 100, the vehicle front-rear direction end portions, the door 100 lower end portions, and the like. In other words, the high-rigidity portion of the door 100 has less dents and is close to a vehicle body structure such as a pillar with the same external force as compared to the central portion of the outer panel 102. The decrease rate of the volume of the space S is small. For this reason, even if a collision occurs, this collision detection device has a pressure gradient ΔP (t) that does not exceed the threshold value ΔP1 depending on the magnitude of the external force when the collision location is a highly rigid portion of the vehicle body. There is a possibility that it is not determined that the collision requires the operation of the protection device 20.

  In order to eliminate this inconvenience, the threshold value ΔP1 may be reduced. However, such a change in the threshold value ΔP1 includes not only the pressure gradient ΔP (t) when the high-rigidity part is a collision part, but also the pressure gradient ΔP (t) when the collision is not caused by a ball hitting. Since there is a possibility of exceeding the threshold value ΔP1, there is a possibility that it is determined that a collision has occurred when it is not a collision. In this state, if the acceleration G when it is not a collision also exceeds the threshold value G0, it is not preferable because it is finally determined that a collision has occurred when it is not a collision.

  Therefore, this collision detection apparatus is configured to determine that a collision has occurred with high accuracy including a collision with such a highly rigid portion. Specifically, first, the collision determination based on the pressure gradient ΔP (t) that has been changed to reduce the threshold value ΔP1 is executed, and the collision with the highly rigid portion is also a collision that requires the operation of the occupant protection device 20. To be judged. At that time, there is a possibility that it is determined as a collision even when the operation of the occupant protection device 20 is not a necessary collision. Therefore, in order to exclude this case from the determination as a collision, the speed of the vehicle body according to the external force is determined. A collision determination based on the change amount ΔV is executed.

  First, in the collision determination based on the pressure gradient ΔP (t) at this time, a threshold value ΔP2 (<ΔP1) is used instead of the threshold value ΔP1 as shown in the collision determination map of FIG. That is, this collision determination is made to determine that a collision requiring the operation of the occupant protection device 20 has occurred when the pressure gradient ΔP (t) is smaller than the collision determination using the threshold value ΔP1. The threshold value ΔP2 is, for example, a value larger than the maximum value by the maximum value or correction amount of the pressure gradient ΔP (t) in the above-described test result when no collision with the high-rigidity site has occurred. The correction amount compensates for, for example, a detection error or calculation error when obtaining the test result, or a detection error or calculation error of the pressure P (t) and the pressure gradient ΔP (t) in the space S when performing the collision determination. Is for the purpose. However, as shown by the one-dot chain line and the two-dot chain line in FIG. 7, when a collision with a highly rigid part (for example, a collision of a pole with the end of the door 100) occurs and when a minor collision occurs, The pressure gradient ΔP (t) related to the collision may not be greatly different. For this reason, when this collision determination map is used, it may be determined that the collision requires the operation of the occupant protection device 20 until a minor collision occurs. However, the minor collision is not a problem because it is determined that the collision does not require the operation of the occupant protection device 20 according to the collision determination map shown in FIG.

  When an impact force (external force) is applied to the door 100, the collision detection device detects the pressure P (t) and the pressure gradient ΔP (t) in the space S detected and calculated at that time, the pressure threshold value P1, and the pressure It is determined whether or not the impact force is a collision that requires the operation of the occupant protection device 20 by comparing with a determination threshold value including each element of the gradient threshold value ΔP2. In this example, as in the above-described determination, the impact force is protected by occupant protection by comparing the pressure gradient threshold value ΔP2 corresponding to the detected pressure P (t) with the calculated pressure gradient ΔP (t). It is determined whether or not the collision requires the operation of the device 20. If the pressure gradient ΔP (t) exceeds the threshold value ΔP2, the collision detection device determines that a collision requiring the operation of the occupant protection device 20 has occurred, and if the pressure gradient ΔP (t) is equal to or less than the threshold value ΔP2. It is determined that the collision does not require the operation of the occupant protection device 20.

  Next, the collision determination based on the vehicle body speed change amount ΔV will be described.

  For example, a collision with a high-rigidity part is compared with a collision in which the pressure gradient ΔP (t) exceeds a threshold value ΔP1 such as a collision with the central portion of the outer panel 102, and the pressure P (t) and the pressure gradient ΔP (t ) Is small, but the external force tends to be transmitted directly to the vehicle body, so the vehicle body speed change ΔV tends to increase (FIG. 8). On the other hand, when the collision does not require the operation of the occupant protection device 20, the vehicle body speed change amount ΔV is smaller than when these collisions occur. Therefore, when an impact force (external force) is applied to the door 100, the collision detection device compares the vehicle body speed change amount ΔV with a predetermined threshold value ΔV 0, so that the impact force is applied to the occupant protection device 20. It is determined whether or not the collision requires action.

  The speed change amount ΔV of the vehicle body is acquired using a speed change amount detection unit. As the speed change amount detection unit, for example, a vehicle speed sensor (vehicle speed detection unit) or a wheel speed sensor (wheel speed detection unit) that enables detection or estimation of the vehicle speed can be used. However, in this example, the acceleration sensor 32 is provided, and information on the acceleration G of the vehicle body can be obtained. Therefore, in this embodiment, the acceleration sensor 32 is also used as a speed change amount detection unit, and the vehicle body speed change ΔV is obtained by integrating the detected acceleration G of the vehicle with time. In this example, the detected lateral acceleration Gy of the vehicle body is integrated to calculate the lateral speed change amount ΔVy of the vehicle body. Further, the threshold value ΔV0 is set to a value larger than the maximum value by the maximum value or correction amount of the speed change amount ΔV in the above-described test result when no collision occurs, for example. The correction amount compensates, for example, an acceleration G detection error and a speed change amount ΔV calculation error when obtaining the test result, and an acceleration G detection error and a speed change amount ΔV calculation error when performing a collision determination. Is for the purpose.

  When an impact force (external force) is applied to the door 100, the collision detection device calculates a lateral speed change amount ΔVy of the vehicle body based on the lateral acceleration Gy detected at that time, and this speed change amount ΔVy. Is compared with a predetermined threshold value ΔVy0 in the lateral direction of the vehicle body to determine whether or not the impact force is a collision that requires the operation of the occupant protection device 20. When the speed change amount ΔVy exceeds the threshold value ΔVy0, the collision detection device determines that a collision requiring the operation of the occupant protection device 20 has occurred, and when the speed change amount ΔVy is equal to or less than the threshold value ΔVy0, It is determined that the collision does not require the operation of the device 20.

  This collision detection device executes a collision determination based on the pressure gradient ΔP (t) using such a threshold value ΔP2 and a collision determination based on the vehicle speed change ΔV. When it is determined that a collision has occurred in each collision determination, a final determination is made that a collision that requires the operation of the occupant protection device 20 has occurred. On the other hand, if it is not determined that a collision has occurred in one of the two collision determinations, it is not determined that a collision requiring the operation of the occupant protection device 20 has occurred. Each of the collision determinations may be executed first, or may be executed in parallel.

  As a result, the collision detection device finally determines that a collision requiring operation of the occupant protection device 20 has occurred when a collision requiring operation of the occupant protection device 20 (including a collision with a highly rigid portion) has occurred. While a determination can be made, when a collision that requires the operation of the occupant protection device 20 has not occurred, a final determination can be made that a collision that requires the operation of the occupant protection device 20 has not occurred.

  By the way, such a final collision determination is higher than the final collision determination based on the collision determination based on the pressure gradient ΔP (t) using the threshold value ΔP1 and the collision determination based on the acceleration G of the vehicle body. While it is possible to determine the collision with the rigid portion, it takes a certain amount of time to calculate the speed change amount ΔV, and thus it takes time until the final determination is made.

  Therefore, in the collision detection apparatus of the present embodiment, the final collision determination (hereinafter referred to as “first path”) based on the collision determination based on the pressure gradient ΔP (t) using the threshold ΔP1 and the collision determination based on the acceleration G of the vehicle body. And a collision determination based on the pressure gradient ΔP (t) using the threshold value ΔP2 and a collision determination based on the vehicle speed change ΔV (hereinafter referred to as “second path collision”). It is called “determination”). In other words, by executing the first path collision determination and the second path collision determination, respectively, in the case of a collision in which an immediate operation of the occupant protection device 20 is required such that the pressure gradient ΔP (t) exceeds the threshold value ΔP1. In the first path collision determination, whether or not a collision requiring the operation of the occupant protection device 20 is finally determined with high responsiveness. Therefore, when such a collision occurs, the occupant protection device 20 can be operated with good responsiveness. On the other hand, in the case of a collision that is less urgent than such a collision (that is, a collision in which the pressure gradient ΔP (t) is equal to or less than the threshold value ΔP1 and exceeds the threshold value ΔP2), this collision is determined by the second path collision determination. It is finally determined whether or not the operation of the occupant protection device 20 is required. Although the second path collision determination is inferior to the first path collision determination, the second path collision determination is used in the case of a collision with a relatively low urgency for operating the occupant protection device 20, so that the occupant is practically used. From the viewpoint of protection, the occupant protection device 20 can be operated at sufficiently early timing. In this collision detection device, the first collision determination unit executes the first path collision determination, and the second collision determination unit executes the second path collision determination.

  The collision detection apparatus may execute the second path collision determination after the first path collision determination is performed first. However, in order to increase the responsiveness of the second path collision determination, as shown in the flowchart of FIG. In addition, it is desirable to execute the first path collision determination and the second path collision determination in parallel.

  The electronic control unit 10 acquires information necessary for executing the first path collision determination and the second path collision determination (step ST1). The necessary information includes at least information on the pressure P (t) in the space S detected by the pressure sensor 31, information on the pressure gradient ΔP (t) in the space S calculated based on the information on the pressure P (t), This is the vehicle body lateral acceleration Gy information detected by the acceleration sensor 32 and the vehicle body lateral velocity change amount ΔVy calculated based on the lateral acceleration Gy information. Here, the electronic control unit 10 may remove noise from the detection signal of the pressure P (t) and calculate the pressure gradient ΔP (t) based on the pressure P (t) after the noise removal.

  The electronic control unit 10 performs the collision determination based on the pressure gradient ΔP (t) in the first path collision determination based on the information on the pressure P (t) in the space S (step ST2), and the second path collision. A collision determination based on the pressure gradient ΔP (t) in the determination is executed (step ST3). In step ST2, it is determined whether or not the pressure gradient ΔP (t) exceeds a threshold value ΔP1. In step ST3, it is determined whether or not the pressure gradient ΔP (t) exceeds the threshold value ΔP2.

  Here, the same pressure gradient ΔP (t) information is used in the collision determination at steps ST2 and ST3. The difference between the steps ST2 and ST3 is only the magnitude of the pressure gradient threshold values ΔP1 and ΔP2 of the collision determination map. For this reason, it is desirable for the electronic control unit 10 to execute the collision determinations of steps ST2 and ST3 simultaneously in parallel. At that time, it is desirable that the electronic control device 10 immediately starts each collision determination when information on the pressure gradient ΔP (t) is obtained, for example. Thereby, in this collision detection apparatus, since each determination result can be obtained substantially simultaneously, the responsiveness of each collision determination is improved.

  In each of the collision determinations, one of the determination results may come out earlier. In such a case, in order to increase the responsiveness of the final determination, it is preferable to proceed to the next calculation process from the end of the determination. For example, in this collision detection apparatus, since the threshold value ΔP2 is smaller than the threshold value ΔP1, the determination result in step ST3 may come out earlier than the determination result in step ST2. In this case, the electronic control unit 10 starts the next collision determination of step ST3 (collision determination of step ST5) even if the determination result of step ST2 is not output.

  When it is determined in step ST2 that the pressure gradient ΔP (t) does not exceed the threshold value ΔP1, the electronic control unit 10 proceeds to step ST7 and determines that the collision does not require the operation of the occupant protection device 20.

  Further, when the electronic control unit 10 determines that the pressure gradient ΔP (t) does not exceed the threshold value ΔP2 in step ST3, the electronic control unit 10 proceeds to step ST8 and determines that the collision does not require the operation of the occupant protection device 20. To do. Note that FIG. 7 does not include anything corresponding to this determination result.

  On the other hand, if the electronic control unit 10 determines in step ST2 that the pressure gradient ΔP (t) exceeds the threshold value ΔP1, the electronic control unit 10 determines that there is a possibility of a collision requiring the operation of the occupant protection device 20, and A collision determination based on the acceleration Gy is executed (step ST4). In this step ST4, it is determined whether or not the lateral acceleration Gy exceeds a threshold value Gy0.

  Further, when it is determined in step ST3 that the pressure gradient ΔP (t) exceeds the threshold value ΔP2, the electronic control device 10 determines that there is a possibility of a collision that requires the occupant protection device 20 to operate, and the second A collision determination based on the lateral speed change amount ΔVy of the vehicle body in the path collision determination is executed (step ST5). In step ST5, it is determined whether or not the speed change amount ΔVy exceeds a threshold value ΔVy0.

  Here, in the collision determination at step ST4, the information of the detected lateral acceleration Gy is used as it is. On the other hand, in the collision determination at step ST5, further calculation is performed based on the information of the lateral acceleration Gy. For this reason, the collision determination in step ST5 is started later than the collision determination in step ST4 if the collision determinations in steps ST2 and ST3 are completed at the same time. However, in order to improve the responsiveness of each of the first path collision determination and the second path collision determination, it is desirable to execute the collision determinations of steps ST4 and ST5 as simultaneously as possible. When the speed change amount ΔVy is acquired without using the information on the lateral acceleration Gy, it is desirable to execute the collision determinations in steps ST4 and ST5 in parallel.

  If the electronic control unit 10 determines in step ST4 that the lateral acceleration Gy does not exceed the threshold value Gy0, the electronic control unit 10 proceeds to step ST7 and determines that the collision does not require the operation of the occupant protection device 20.

  Further, when it is determined in step ST5 that the speed change amount ΔVy does not exceed the threshold value ΔVy0, the electronic control device 10 proceeds to step ST8 and determines that the collision does not require the operation of the occupant protection device 20.

  On the other hand, if it is determined in step ST4 that the lateral acceleration Gy exceeds the threshold value Gy0, the electronic control device 10 determines that there is a possibility of a collision that requires the operation of the occupant protection device 20. In this example, since it is already determined that there is a possibility of a collision in the collision determination based on the pressure gradient ΔP (t) in the first path collision determination, the electronic control unit 10 determines that the lateral acceleration Gy is the threshold value Gy0 in step ST4. If it is determined that the vehicle has exceeded the maximum, a final determination is made that a collision requiring the operation of the occupant protection device 20 has occurred (step ST6).

  The electronic control device 10 also determines that there is a possibility of a collision that requires the occupant protection device 20 to operate even when it is determined in step ST5 that the speed change amount ΔVy exceeds the threshold value ΔVy0. In this example, since it is already determined that there is a possibility of a collision in the collision determination based on the pressure gradient ΔP (t) in the second path collision determination, the electronic control unit 10 determines that the speed change amount ΔVy is a threshold value in step ST5. When it is determined that ΔVy0 is exceeded, the process proceeds to step ST6, and a final determination is made that a collision requiring the operation of the occupant protection device 20 has occurred.

  By the way, the detection of the lateral acceleration Gy and the calculation of the speed change amount ΔVy are executed separately from the detection of the pressure P (t) and the calculation of the pressure gradient ΔP (t). Therefore, it is desirable that the collision determination in step ST4 starts immediately when the lateral acceleration Gy is detected in step ST1. In other words, in the first path collision determination, the collision determination based on the pressure gradient ΔP (t) is started simultaneously with the acquisition of the information of the pressure gradient ΔP (t), and based on the lateral acceleration Gy along with the acquisition of the information of the lateral acceleration Gy. It is desirable to start the collision determination so that the respective collision determinations are executed in parallel as much as possible. This is because the responsiveness up to the final determination in the first path collision determination is improved. Similarly, it is desirable that the collision determination at step ST5 starts immediately when the speed change amount ΔVy is calculated at step ST1. That is, in the second path collision determination, the collision determination based on the pressure gradient ΔP (t) is started simultaneously with the acquisition of the information of the pressure gradient ΔP (t), and the speed change amount ΔVy is acquired with the acquisition of the information of the speed change amount ΔVy. It is desirable that each collision determination is executed in parallel as much as possible by starting the collision determination based on. This is because the responsiveness up to the final determination is improved even in the second path collision determination.

  When the final determination of step ST6 is obtained, the electronic control device 10 operates the occupant protection device 20 (step ST9). Here, since the side collision is taken as an example, the electronic control device 10 activates the occupant protection device 20 that is operated in the case of a side collision such as a side airbag or a curtain shield airbag.

  Specifically, in the first path collision determination, if there is a collision that requires quick activation of the occupant protection device 20 such that the pressure gradient ΔP (t) exceeds the threshold value ΔP1 (solid line in FIGS. 5 and 6), step The collision determination based on the pressure gradient ΔP (t) in ST2 and the collision determination based on the acceleration G of the vehicle body in step ST4 determine that a collision that requires the operation of the occupant protection device 20 has occurred. A final determination is made that it has occurred. On the other hand, in the second path collision determination, when such a collision occurs (solid line in FIGS. 7 and 8), the collision determination based on the pressure gradient ΔP (t) in step ST3 and the vehicle body speed change ΔV in step ST5. Since it is determined that a collision that requires the operation of the occupant protection device 20 has occurred, a final determination is made that such a collision has occurred. Thus, when there is a collision such that the pressure gradient ΔP (t) exceeds the threshold value ΔP1, a collision that requires the operation of the occupant protection device 20 occurs in both the first path collision determination and the second path collision determination. Since the final determination is made, the occupant protection device 20 can be operated regardless of the route. However, in this collision detection apparatus, as described above, the determination result of the first path collision determination can be obtained with better responsiveness than the second path collision determination due to the calculation delay of the speed change amount ΔV. Therefore, in the case of a collision that requires quick activation of the occupant protection device 20, the occupant protection device 20 can be operated with high responsiveness based on the determination result of the first path collision determination.

  Next, when a collision (for example, a collision of a pole with the end portion of the door 100) occurs in a highly rigid portion (a dashed line in FIGS. 5 and 6), in the first path collision determination, the pressure gradient ΔP ( The collision determination based on t) determines that the collision does not require the operation of the occupant protection device 20, and the collision determination requires the operation of the occupant protection device 20 based on the collision determination based on the vehicle body acceleration G in step ST4. Judgment is made that happened. Therefore, in the case of such a collision, in the first path collision determination, a final determination is made that the collision does not require the operation of the occupant protection device 20. However, in the case of such a collision, in the second path collision determination, the collision determination based on the pressure gradient ΔP (t) in step ST3 and the collision determination based on the vehicle body speed change ΔV in step ST5 respectively. Since it is determined that a collision requiring the operation of the protection device 20 has occurred (the dashed line in FIGS. 7 and 8), a final determination is made that such a collision has occurred. Therefore, in this occupant protection system 1, the occupant protection device 20 can be operated even when a collision occurs in such a highly rigid portion.

  When a minor collision occurs in this example (two-dot chain line in FIGS. 5 and 6), the occupant protection device is determined by the collision determination based on the pressure gradient ΔP (t) in step ST2 in the first path collision determination. It is determined that the collision does not require the movement of the vehicle 20, and the collision determination based on the acceleration G of the vehicle body in step ST4 determines that the collision requiring the operation of the occupant protection device 20 has occurred. Therefore, in the case of such a collision, in the first path collision determination, a final determination is made that the collision does not require the operation of the occupant protection device 20. On the other hand, in the second path collision determination, it is determined by the collision determination based on the pressure gradient ΔP (t) in step ST3 that a collision requiring the operation of the occupant protection device 20 has occurred, and the vehicle body in step ST5 By the collision determination based on the speed change amount ΔV, it is determined that the collision does not require the operation of the occupant protection device 20 (two-dot chain line in FIGS. 7 and 8). Therefore, even in the second path collision determination, in the case of such a collision, a final determination is made that the collision does not require the operation of the occupant protection device 20. Therefore, in this occupant protection system 1, when such a minor collision occurs, the activation of the occupant protection device 20 can be prohibited regardless of which route is taken.

  In this way, the collision detection device has determined that a collision requiring operation of the occupant protection device 20 has occurred when it is finally determined that a collision has occurred in at least one of the first path collision determination and the second path collision determination. Determine.

  As described above, in the case of a collision that quickly activates the occupant protection device 20, this collision detection device can finally determine with high responsiveness that the collision requires the operation of the occupant protection device 20. Accordingly, the occupant protection system 1 can quickly activate the occupant protection device 20, so that the occupant protection function can be enhanced. In addition, the collision detection device and the occupant protection system 1 can finally determine that the collision requires the operation of the occupant protection device 20 even when a collision occurs in a highly rigid portion. Can be activated. In addition, the collision detection device and the occupant protection system 1 are used when the occupant feels that the necessity of the operation of the occupant protection device 20 is low and it is not necessary to determine that the collision has occurred (for example, the operation of the occupant protection device 20 is not desired). In the case of a minor collision), it is possible to make a final determination that the collision is not occurring, so that the activation of the occupant protection device 20 can be prohibited. For this reason, this occupant protection system 1 can suppress unnecessary activation of the occupant protection device 20. For example, even if a collision that requires the operation of the occupant protection device 20 following the minor collision occurs, The occupant protection device 20 can be activated. Further, the collision detection device and the occupant protection system 1 can also suppress the occupant's uncomfortable feeling that the occupant protection device 20 is operated even though the necessity of operation is felt low.

  As described above, the collision detection device and the occupant protection system 1 can improve the determination accuracy of the collision determination. Accordingly, the occupant protection system 1 can suppress the operation of the occupant protection device 20 due to an erroneous determination, thereby reducing the labor and cost required for repairing the occupant protection device 20, that is, replacing the deployed airbag or refilling the explosive. be able to.

  Further, in the above example, the case of a side collision has been described, so the space S of the door 100 is described. However, if such a space S exists in the front bumper, the rear bumper, or the vehicle body portion to which these are attached, this occupant The protection system 1 may be applied at the time of frontal collision or rear-end collision. However, it is desirable that the acceleration sensor for detecting the longitudinal acceleration Ga is disposed at a location that is difficult to be deformed by a frontal collision or a rearward collision. The occupant protection device 20 in this case is an airbag or the like built in the steering wheel. In addition, the high rigidity portion in this case is, for example, a corner of a front bumper or a rear bumper, a portion where the front bumper or the rear bumper is attached to the vehicle body side, or the like.

  In the above example, the space S is composed of an outer member of the vehicle and an inner member of the vehicle, but the space S may be composed of one member. Good.

  In addition, the occupant protection system 1 may be applied to determine whether or not the operation of the seat belt with a pretensioner mechanism (occupant protection device) that instantaneously winds up the seat belt in the event of a collision and enhances the occupant restraint effect. .

DESCRIPTION OF SYMBOLS 1 Crew protection system 10 Electronic controller 20 Crew protection device 31 Pressure sensor 32 Acceleration sensor 100 Door 101 Inner panel 102 Outer panel 103 Door trim S Space

Claims (3)

A pressure detector for detecting the pressure of a space configured close to the inside of the exterior member of the vehicle;
A speed change amount detecting unit for detecting a speed change amount of the vehicle body;
An acceleration detector for detecting the acceleration of the vehicle body;
A first collision determination unit that performs a final determination that a collision has occurred when it is determined that a collision has occurred based on an amount of change in the pressure per unit time and a collision has occurred based on the acceleration; ,
A second collision determination is made to make a final determination that a collision has occurred when it is determined that a collision has occurred based on the amount of change in pressure per unit time, and a collision has occurred based on the amount of change in speed. With the department ,
The second collision determination unit determines that a collision has occurred when the amount of change in pressure per unit time is smaller than that of the first collision determination unit,
A collision detection apparatus , wherein a collision is determined when it is finally determined that a collision has occurred in at least one of the first collision determination unit and the second collision determination unit . The collision determination based on the pressure change amount per unit time by the first collision determination unit, the collision determination based on the acceleration by the first collision determination unit, and the unit time by the second collision determination unit the determination of a collision based on the amount of change in the pressure of the collision detection device according to claim 1, characterized in that to perform a determination of a collision based on the velocity change amount by the second collision determining unit simultaneously in parallel . A pressure detector for detecting the pressure of a space configured close to the inside of the exterior member of the vehicle;
A speed change amount detecting unit for detecting a speed change amount of the vehicle body;
An acceleration detector for detecting the acceleration of the vehicle body;
A first collision determination unit that performs a final determination that a collision has occurred when it is determined that a collision has occurred based on an amount of change in the pressure per unit time and a collision has occurred based on the acceleration; ,
A second collision determination is made to make a final determination that a collision has occurred when it is determined that a collision has occurred based on the amount of change in pressure per unit time, and a collision has occurred based on the amount of change in speed. And
An occupant protection device for protecting occupants in the passenger compartment;
An occupant protection control unit that operates the occupant protection device when it is finally determined that a collision has occurred ,
The second collision determination unit determines that a collision has occurred when the amount of change in pressure per unit time is smaller than that of the first collision determination unit,
When the first collision determination unit and the at least one collision of said second collision determination unit is finally determined to have occurred, the occupant protection system, characterized in that Ru is operating the occupant protection device.

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