Impact determination device

Abstract

An impact determination device is provided with: an internal sensor that includes an acceleration sensor that detects accelerations including respective components in the front-rear direction and the left-right direction of a host vehicle; an external sensor that detects an object around the host vehicle; a threshold value setting unit that sets a threshold value for determining an impact on the host vehicle by an object; and an impact determination unit that determines an impact when the acceleration of each of the components is equal to or greater than a threshold value. The threshold value setting unit recognizes the impact form of the object on the vehicle on the basis of the detection result of the external sensor, and sets a threshold value for each component of the acceleration in accordance with the impact form.

Description

Technical Field

[0001] The present disclosure relates to an impact determination device. Background Art

[0002] Conventionally, there is known a device that detects the acceleration of a vehicle in the longitudinal and lateral directions and determines the type of collision of the vehicle by comparing the detected acceleration with a collision type determination threshold value stored in advance as a two-dimensional map (for example, Japanese Patent Application Laid-Open No. 2013-220743). Summary of the Invention

[0003] There is a device that determines whether an object has impacted or collided with a vehicle based on the comparison of the detected values ​​of the vehicle's longitudinal acceleration and lateral acceleration with threshold values. This device has been researched to optimize the relationship between acceleration and the threshold value, taking into account the type of collision between the vehicle and the object. However, in this prior art, the collision type is determined solely by comparing acceleration with the threshold value, leaving room for improvement based on various perspectives.

[0004] A technical solution of the present disclosure relates to an impact determination device comprising:

[0005] An acceleration sensor that detects acceleration including components in the vehicle's front-to-back and left-to-right directions;

[0006] External sensors that detect objects around the vehicle;

[0007] a threshold setting unit that sets a threshold for determining an impact caused by an object on the vehicle; and

[0008] The impact determination unit determines an impact when the acceleration of each of the components is equal to or greater than a threshold value.

[0009] a threshold setting unit,

[0010] Identify the impact form of the object on the vehicle based on the detection results of external sensors,

[0011] Depending on the type of shock, a threshold is set for each component of acceleration.

[0012] In an impact determination device according to one aspect of the present disclosure, a threshold setting unit identifies the type of impact of an object on a vehicle based on detection results from an external sensor. A threshold is set for each acceleration component according to the impact type. This allows the threshold to be set based on the impact type based on the detection results from the external sensor. This allows for more appropriate determination of the impact of an object on a vehicle, compared to, for example, setting the threshold based solely on the impact type identified based on the detection results from the acceleration sensor.

[0013] In one embodiment, it may be,

[0014] a threshold setting unit,

[0015] Identify offset collisions of objects against the vehicle as a form of impact

[0016] According to the offset of the offset collision, the threshold value is set for each component of the acceleration.

[0017] In this case, since the threshold value is set for each component of the acceleration according to the offset amount, it is possible to improve the accuracy of determining the impact of the object on the vehicle.

[0018] According to the impact determination device according to one aspect of the present disclosure, it is possible to more appropriately determine an impact on a vehicle caused by an object, compared to, for example, a case where a threshold value is set based solely on the detection result of an acceleration sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0020] Figure 1 is a block diagram showing a vehicle including an impact determination device according to an embodiment;

[0021] Figure 2A FIG. 1 is a diagram showing an example of mounting an acceleration sensor; Figure 2B FIG. 1 is a diagram showing another example of mounting an acceleration sensor;

[0022] Figure 3A FIG. 1 is a diagram showing an example of an impact form; Figure 3B FIG. 1 is a diagram showing another example of an impact form; Figure 3C FIG. 1 is a diagram showing another example of an impact form;

[0023] Figure 4A is a diagram showing an example of a time series graph of acceleration; Figure 4B is shown with Figure 4A A diagram showing an example of acceleration trajectories and threshold values ​​corresponding to each component of acceleration on a two-dimensional plane;

[0024] Figure 5A 1 is a diagram showing an example of a time series graph of acceleration without a phase difference; Figure 5B It shows the Figure 5A A diagram showing an example of a trajectory and a threshold value obtained by plotting the acceleration of ;

[0025] Figure 6A 1 is a diagram showing an example of a timing chart of acceleration with a phase difference; Figure 6BIt shows the Figure 6A A diagram showing an example of a trajectory and a threshold value obtained by plotting the acceleration of ;

[0026] Figure 7A FIG. 1 is a diagram showing another example of a timing chart of acceleration with a phase difference; Figure 7B It shows the Figure 7A A diagram showing an example of a trajectory and a threshold value obtained by plotting the acceleration of ;

[0027] Figure 8A It shows Figure 1 A flowchart of an example of processing of the impact determination ECU; and, Figure 8B It shows Figure 8A Flowchart of an example of processing for identifying an impact form and setting a threshold value. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0029] Figure 1 This is a block diagram showing a vehicle including an impact determination device according to an embodiment. Figure 1 The figure shows a host vehicle (vehicle) 50 equipped with an impact determination device 100. The impact determination device 100 is a device for determining an impact caused by an object on the host vehicle 50 by impact detection using biaxial acceleration. The host vehicle 50 is, for example, a passenger car. The object is, for example, another vehicle such as a passenger car traveling around the host vehicle 50. The other vehicle is not limited to a passenger car. The object is not limited to another vehicle.

[0030] "Impact caused by an object on the vehicle 50" refers, for example, to a collision between the vehicle 50 and the object. "Impact determination" in this disclosure is not limited to determining whether a collision has occurred. The impact determination device 100 herein is, for example, part of a system that deploys an airbag when an impact is detected.

[0031] like Figure 1 As shown, the impact determination device 100 includes an internal sensor 1 , an external sensor 2 , an airbag actuator 3 , and an impact determination ECU (Electronic Control Unit) 10 .

[0032] The impact determination ECU 10 is an electronic control unit that includes a CPU (Central Processing Unit) and a storage unit. The storage unit is comprised of, for example, ROM (Read Only Memory), RAM (Random Access Memory), and EEPROM (Electrically Erasable Programmable Read-Only Memory). In the impact determination ECU 10, various functions are implemented by, for example, the CPU executing programs stored in the storage unit. The impact determination ECU 10 may also be comprised of multiple electronic units.

[0033] Internal sensor 1 is a detection device that detects the driving state of host vehicle 50. Internal sensor 1 includes an acceleration sensor. The acceleration sensor detects the acceleration of host vehicle 50. The acceleration sensor transmits the detected acceleration information to impact determination ECU 10. Internal sensor 1 may also include a vehicle speed sensor and a yaw rate sensor.

[0034] The acceleration sensor of the interior sensor 1 detects acceleration including components in the front-rear direction and the left-right direction of the host vehicle 50 . Figure 2A This figure shows an example of an acceleration sensor installation. This acceleration sensor incorporates a dual-axis (biaxial) sensor within a single housing, taking into account factors such as reducing the number of sensors, reducing wiring harnesses, and increasing the flexibility of the installation layout. For example, the acceleration sensor of internal sensor 1 is assigned the front-to-back direction of vehicle 50 (the vehicle's travel direction) as the X-axis, and the left-to-right direction of vehicle 50 (the left-to-right direction perpendicular to the vehicle's travel direction) as the Y-axis. The acceleration sensor of internal sensor 1 detects the X-axis acceleration in the front-to-back direction of vehicle 50 and the Y-axis acceleration in the left-to-right direction of vehicle 50.

[0035] In addition, the acceleration sensor of the internal sensor 1 is not limited to a sensor having a built-in dual-axis sensor in one housing. Figure 2B As shown in the vehicle 50A, acceleration sensors 1a and 1b, each of which is a uniaxial sensor, are arranged adjacent to each other in a housing. Alternatively, the uniaxial acceleration information of the acceleration sensors 1a and 1b may be synthesized and processed as biaxial (two-axis) acceleration information.

[0036] The external sensor 2 is a detection device that detects objects around the vehicle 50. The external sensor 2 includes at least one of a camera and a radar sensor. The camera is a photographing device that photographs the external conditions of the vehicle 50. The camera is, for example, installed on the inner side of the front windshield of the vehicle 50 to photograph the front of the vehicle 50. The camera sends the photographed image related to the external conditions of the vehicle 50 to the impact determination ECU 10. The radar sensor is a detection device that uses radio waves (such as millimeter waves) or light to detect objects around the vehicle 50. The radar sensor includes, for example, a millimeter wave radar or a laser radar (LiDAR: Light Detection and Ranging). The radar sensor sends information about the detected object to the impact determination ECU 10.

[0037] The airbag actuator 3 is an actuator for operating an airbag device (not shown). Under predetermined conditions, such as a collision of the vehicle 50, the airbag actuator 3 receives an inflation control signal from the impact determination device 100. Upon receiving the inflation control signal, the airbag actuator 3 operates to deploy the airbag device. The inflation control signal is a signal instructing the airbag actuator 3 to drive.

[0038] Next, the functional configuration of the impact determination ECU 10 will be described. The impact determination ECU 10 includes an information recognition unit 11 , a threshold setting unit 12 , and an impact determination unit 13 .

[0039] The information recognition unit 11 identifies the driving state of the host vehicle 50 based on the detection results of the internal sensor 1. The driving state includes the acceleration of the host vehicle 50. The information recognition unit 11 identifies the acceleration of the host vehicle 50 along two axes based on the acceleration information from the acceleration sensor. The information recognition unit 11 identifies the acceleration, including the components in the front-back direction and the left-right direction of the host vehicle 50, based on the detection results of the internal sensor 1.

[0040] The information recognition unit 11 recognizes the external environment of the host vehicle 50 based on the detection results of the external sensor 2. The external environment includes the relative position, relative speed, and movement direction of surrounding objects relative to the host vehicle 50. The external environment may also include information on the types of objects such as other vehicles, pedestrians, and bicycles.

[0041] The threshold setting unit 12 sets an acceleration threshold (threshold) for determining an impact caused by an object on the host vehicle 50. The acceleration threshold is a threshold for each component of acceleration used to determine an impact caused by an object on the host vehicle 50. The acceleration threshold includes a threshold for the X-axis acceleration in the front-to-back direction of the host vehicle 50 and a threshold for the Y-axis acceleration in the left-to-right direction of the host vehicle 50.

[0042] The threshold setting unit 12 identifies the type of impact of an object on the host vehicle 50 based on the detection results of the external sensor 2. The impact type refers to the type of force applied to the host vehicle 50 by the object when it strikes the host vehicle 50. The magnitude and direction of the force vary depending on the impact type. The force applied to the host vehicle 50 here can refer to the force at the location where the host vehicle 50 collides with the object.

[0043] The impact type can be a collision type in which an object (e.g., another vehicle, a pole, a wall, etc.) collides with the vehicle 50. Examples of collision types include head-on collision, oblique collision, and offset collision. A head-on collision is a collision in which an object collides with the front surface of the vehicle 50 in a direction opposite to the direction of travel. A head-on collision includes a frontal collision. Figure 3A As shown in FIG. 1 , when the angle between the direction of travel of the other vehicle 60 and the direction of travel of the host vehicle 50 is less than a predetermined value, the collision is a head-on collision. Figure 3B As shown, if the amount of deviation (offset) of the other vehicle 62 in the left-right direction relative to the traveling direction of the host vehicle 50 is less than a predetermined value, the collision type is a head-on collision. The offset can be, for example, the amount of deviation in the left-right direction of the centerline of the other vehicle 62 in the front-to-back direction relative to the centerline of the host vehicle 50 in the front-to-back direction.

[0044] Oblique collision is a collision in which the direction of travel of the object has an angle greater than a predetermined value relative to the direction of travel of the host vehicle 50. Figure 3A As shown, when the angle formed by the traveling direction of the other vehicle 61 with respect to the traveling direction of the host vehicle 50 is equal to or greater than a predetermined value, the collision type is an oblique collision.

[0045] An offset collision is a collision in which an object collides with the vehicle 50 in a manner that deviates in the left-right direction relative to the direction of travel of the vehicle 50. Figure 3B As shown, when the offset amount of the other vehicle 63 relative to the traveling direction of the host vehicle 50 is equal to or greater than a predetermined value, the collision type is an offset collision.

[0046] In addition, if Figure 3C As shown, even when other vehicles 64 and 65 collide with host vehicle 50 at the same location, the collision type may differ. For example, if the offset of other vehicle 64 is less than a predetermined value, the collision type of other vehicle 64 and host vehicle 50 may be an oblique collision. If the offset of other vehicle 65 is greater than a predetermined value, the collision type of other vehicle 65 and host vehicle 50 may be an offset collision.

[0047] The threshold setting unit 12 sets the acceleration threshold for each acceleration component according to the impact type. The acceleration threshold can be set by adjusting the force applied to the host vehicle 50 by an object colliding with the host vehicle 50 and transmitted along the body of the host vehicle 50 to the internal sensor 1, such as by performing simulations or collision tests in advance.

[0048] When the acceleration is equal to or greater than the acceleration threshold for each of the acceleration components, the impact determination unit 13 determines an impact. For example, the impact determination unit 13 compares the recognized acceleration of the host vehicle 50 with a set acceleration threshold for each component.

[0049] The impact determination unit 13, for example, compares the forward-backward component of the identified acceleration with the forward-backward component of a set acceleration threshold. The impact determination unit 13 also compares the forward-backward component of the identified acceleration with the forward-backward component of a set acceleration threshold. If the acceleration for both the forward-backward and the backward-backward components is greater than the acceleration threshold, the impact determination unit 13 determines an impact (makes an impact determination). If the acceleration for either the forward-backward or backward-backward components is less than the acceleration threshold, the impact determination unit 13 does not determine an impact (does not make an impact determination).

[0050] The setting of the acceleration threshold value by the threshold value setting unit 12 will be described in more detail. Figure 4A : is a diagram showing an example of a time series chart of acceleration. Figure 4A 3 shows an example of the X-axis acceleration and Y-axis acceleration corresponding to the force when an object hits the host vehicle 50 and the force applied to the host vehicle 50 is transmitted along the body of the host vehicle 50 to the acceleration sensor.

[0051] exist Figure 4A In the figure, dashed lines (1) to (5) are marked for a portion of the maximum and minimum values ​​of the X-axis acceleration. The dashed lines (1) to (5) sometimes deviate from the positions of the maximum and minimum values ​​of the Y-axis acceleration in the curve of the Y-axis acceleration. That is, there is a case where the waveform of the X-axis acceleration and the waveform of the Y-axis acceleration have a phase difference. This phase difference may vary depending on, for example, the difference in the structure of the body (platform) of the vehicle 50, the difference in the equipment of the vehicle 50, the installation position of the acceleration sensor (deviation from the center of the vehicle in the left and right directions, etc.), the collision type, etc. The structure of the body of the vehicle 50 may differ depending on the vehicle grade (model) of the vehicle 50, the delivery destination of the vehicle 50, etc. In this way, the transmission path of the impact force applied to the vehicle 50 to the acceleration sensor may become very complicated. In addition, not only the phase difference, but also the size of the peak values ​​corresponding to each other in the waveforms of the X-axis acceleration and the Y-axis acceleration detected by the acceleration sensor may be different.

[0052] The threshold value setting unit 12 sets the acceleration threshold value in consideration of such a phase difference and a difference in the magnitude of the peak value. Figure 4B is shown with Figure 4A A diagram showing an example of acceleration trajectories on a two-dimensional plane and threshold values ​​corresponding to each component of acceleration.

[0053] For ease of explanation, Figure 4B On the two-dimensional plane, the shaded area is drawn with respect to the acceleration threshold. Figure 4B In the example, the shaded area is set to a convex (inverted T-shaped) area symmetrical about the X-axis on a two-dimensional plane using the coordinates (x1, y1) and (x2, y2) of points P1 and P2 as acceleration thresholds. Figure 4B The acceleration threshold is the normal threshold TH1. Normal threshold TH1 is, for example, an acceleration threshold used when a head-on collision with another vehicle on the host vehicle 50 is identified as the type of impact. Alternatively, normal threshold TH1 is, for example, an acceleration threshold used when, based on the detection results of the external sensor 2, it is estimated by a known method that the possibility of the host vehicle 50 colliding with an object is low.

[0054] exist Figure 4B On a two-dimensional plane, if the position where the X-axis acceleration and Y-axis acceleration are plotted is outside the shaded area, this means that the acceleration for both the front-back and left-right components is above the acceleration threshold, and an impact is detected. If the position where the X-axis acceleration and Y-axis acceleration are plotted is within the shaded area, this means that the acceleration for either the front-back or left-right components is below the acceleration threshold, and no impact is detected.

[0055] In the vehicle 50, the airbag is activated when an impact is detected, so the acceleration threshold is set so that the impact is not erroneously detected. The position where the X-axis acceleration and the Y-axis acceleration are plotted according to the following impact is defined so that they are within the shaded area. Figure 4B The impact is caused by, for example, vibrations during driving due to normal acceleration, deceleration, and steering of the vehicle 50, input from uneven roads, or minor collisions with objects. Furthermore, to reduce the computational load of the impact determination ECU 10, the acceleration threshold may be set so as to define a shaded area with a "straight outer edge."

[0056] In addition, Figure 4B , positions (1) to (5) are shown along the trajectory of the white arrows. Figure 4B Position (1) to position (5) and the two-dimensional plane Figure 4AThe X-axis acceleration and Y-axis acceleration at the time of the dotted line (1) to the dotted line (5) correspond to the positions where they are plotted. Sometimes, there is a difference between the waveform of the X-axis acceleration and the waveform of the Y-axis acceleration. Figure 4A In the case of such a phase difference, Figure 4B As shown by the white arrows in FIG. 1 , the positions of the X-axis acceleration and the Y-axis acceleration are depicted to move in a complex manner on the two-dimensional plane.

[0057] Figure 5A This is a diagram showing an example of a time chart of acceleration without a phase difference. Figure 5B It shows the Figure 5A The following diagram shows an example of the trajectory and threshold value obtained by plotting the acceleration of . Figure 5A As shown in FIG. 1 , for example, in the case of a positive impact, the phase difference between the waveform of the X-axis acceleration and the waveform of the Y-axis acceleration (the difference in the time of the peaks indicated by asterisks in the figure) is within a predetermined time difference (almost simultaneously). In this case, Figure 5B As shown, the position where the X-axis acceleration and Y-axis acceleration are plotted (the tips of the white arrows) is outside the shaded area defined by the normal threshold value TH1, allowing for appropriate impact determination. The shaded area defined by the normal threshold value TH1 can be defined by multiple straight lines approximately perpendicular to the X-axis or Y-axis on a two-dimensional plane.

[0058] However, due to the phase difference and peak value difference between the X-axis acceleration waveform and the Y-axis acceleration waveform, the positions of the X-axis acceleration and the Y-axis acceleration may not be as accurate as the ones shown in the figure. Figure 5A and Figure 5B In this case, there is a possibility that an error may be made and the impact cannot be determined.

[0059] Figure 6A This is a diagram showing an example of a time chart of acceleration with a phase difference. Figure 6B It shows the Figure 6A For example, in the case where the impact is an oblique collision, or in the case where the impact is an oblique collision and an offset collision, it is possible that Figure 6A The acceleration waveform is as shown. In cases where the Y-axis acceleration waveform peaks earlier than the X-axis acceleration waveform, resulting in a phase difference exceeding a predetermined time difference, the acceleration threshold can be set to a first correction threshold TH2 using the coordinates (x1, y3) of point P3. In this case, the shaded area defined by the first correction threshold TH2 includes the portion defined by straight lines inclined with respect to the X and Y axes on the two-dimensional plane.

[0060] The acceleration threshold can be set to a value that includes the coordinate y3. The absolute value of y3 is smaller than the absolute value of y1. The value of coordinate y3 can be set, for example, by calculating the inclination (slope) of the inclined line based on the phase difference and peak magnitude difference between the X-axis acceleration waveform and the Y-axis acceleration waveform, based on simulations or collision test results for oblique impacts. The inclined line can include multiple inflection points and can be asymmetrical about the X-axis.

[0061] Therefore, if Figure 6B As shown, the position where the X-axis acceleration and the Y-axis acceleration are plotted (the tips of the white arrows) exists outside the hatched area defined by the first correction threshold value TH2, and the impact can be appropriately determined.

[0062] The threshold setting unit 12 may recognize an offset collision of another vehicle against the host vehicle 50 as the impact type and set the acceleration threshold for each acceleration component according to the offset amount of the offset collision. Figure 7A This is a diagram showing another example of a time series graph of acceleration with a phase difference. Figure 7B It shows the Figure 7A For example, in the case where the impact is an offset collision with a large offset amount, or an offset collision that is not an oblique collision, it is possible that Figure 7A The acceleration waveform is as shown. In this case, there may be a phase difference exceeding the predetermined time difference, such that the X-axis acceleration waveform peaks earlier than the Y-axis acceleration waveform. In this case, the acceleration threshold may be set to a second corrected threshold TH3 using the coordinates (x1, y4) and (x2, y4) of points P4 and P5. In this case, the shaded area defined by the second corrected threshold TH3 does not need to include the portion defined by straight lines inclined with respect to the X and Y axes on the two-dimensional plane.

[0063] The acceleration threshold value can be set to include a value of coordinate y4. The absolute value of y4 can be smaller than the absolute value of y1. The absolute value of y4 can also be larger than the absolute value of y3. The value of coordinate y4 can be set, for example, by calculating the difference from y1 based on the phase difference and peak value difference between the waveforms of the X-axis acceleration and the Y-axis acceleration, based on simulations or collision test results for offset collisions.

[0064] Therefore, if Figure 7B As shown, the locus (white arrow) depicting the positions of the X-axis acceleration and the Y-axis acceleration passes outside the hatched area defined by the second correction threshold value TH3, and the impact can be appropriately determined.

[0065] The acceleration threshold can be updated by an update process from the server SV provided at the center C. The sending unit 20 of the impact determination device 100 and the receiving unit 30 of the center C are configured to be able to communicate via well-known wireless communications. The server SV may be a conventional computer. For example, when insights that can further improve safety are obtained, update information of the acceleration threshold based on such insights is stored in the storage unit 40 of the server SV. The update unit 41 can use the update information of the storage unit 40 to update the acceleration threshold of the vehicle 50. However, the "update" here refers to an update within the following range: the acceleration threshold of the vehicle 50 that is pre-set at the time of initial sale satisfies the certification test such as collision safety, and it can be demonstrated that even if the acceleration threshold is updated, the certification test results will not be damaged at all and safety will be improved.

[0066] Operation of the impact determination device

[0067] Next, the operation of the impact determination device 100 will be described with reference to the drawings. Figure 8A It shows Figure 1 A flowchart of an example of processing of the impact determination ECU. Figure 8B It shows Figure 8A Flowchart of an example of processing for identifying an impact form and setting a threshold value. Figure 8A and Figure 8B The processing may be executed when the vehicle speed of the host vehicle is equal to or greater than a predetermined vehicle speed threshold.

[0068] like Figure 8A As shown, as S11, the impact determination ECU 10 of the impact determination device 100 identifies acceleration including components in the front-rear direction and the left-right direction via the information recognition unit 11. The information recognition unit 11 identifies acceleration including components in the front-rear direction and the left-right direction of the host vehicle 50 based on the detection results of the internal sensor 1.

[0069] In S12, the impact determination ECU 10 identifies the impact type and sets the acceleration threshold value through the threshold setting unit 12. The threshold setting unit 12 identifies the impact type of other vehicles on the vehicle 50 based on the detection results of the external sensor 2. The threshold setting unit 12 sets the acceleration threshold value for each component of the identified acceleration according to the impact type. The threshold setting unit 12 sets the acceleration threshold value in the front-to-back direction for the front-to-back direction component of the identified acceleration according to the impact type. The threshold setting unit 12 sets the acceleration threshold value in the left-to-right direction for the left-to-right direction component of the identified acceleration according to the impact type. The impact determination ECU 10 can, for example, Figure 8B The processing is the specific processing of S12.

[0070] like Figure 8BAs shown, in S21, the impact determination ECU 10 uses the threshold setting unit 12 to determine whether the offset is less than the offset threshold. The threshold setting unit 12 identifies the offset of the other vehicle relative to the host vehicle 50 based on the detection results of the external sensor 2, for example, and compares the offset with the offset threshold. If the offset is less than the offset threshold, the threshold setting unit 12 may identify a head-on collision of the other vehicle against the host vehicle 50 as the impact type. If the offset is greater than the offset threshold, the threshold setting unit 12 may identify an offset collision of the other vehicle against the host vehicle 50 as the impact type.

[0071] If it is determined that the offset amount is smaller than the offset threshold value (S21: YES), in S22, the impact determination ECU 10 sets a normal threshold value for each acceleration component via the threshold setting unit 12. The threshold setting unit 12 is, for example, Figures 4A to 4B 、 Figures 5A to 5B In this way, x1, y1, x2, y2, etc. are read for each component of acceleration, and P1 and P2 are plotted on a two-dimensional plane, and the normal threshold TH1 passing through P1 and P2 is set as the acceleration threshold. In addition, there is a case where the offset is less than the offset threshold, and the threshold setting unit 12 infers that the possibility of the vehicle 50 colliding with the object is low based on the detection result of the external sensor 2 by a well-known method. In this case, the normal threshold TH1 can be set as the acceleration threshold without specifically identifying the impact type. After that, the impact determination ECU 10 ends this time. Figure 8B Processing, return to Figure 8A Processing of S13.

[0072] If the offset amount is determined to be greater than the offset threshold (S21: No), in S23, the impact determination ECU 10 uses the threshold setting unit 12 to determine whether the angle is less than the angle threshold. The threshold setting unit 12 identifies the angle of the other vehicle relative to the host vehicle 50 based on the detection results of the external sensor 2 and compares the angle with the angle threshold. If the angle is less than the angle threshold, the threshold setting unit 12 may identify an offset collision, not an oblique collision, as the impact type. If the angle amount is greater than the angle threshold, the threshold setting unit 12 may identify both an oblique collision and an offset collision (both an oblique collision and an offset collision) as the impact type.

[0073] If it is determined that the angle is smaller than the angle threshold (S23: YES), in S24, the impact determination ECU 10 sets the second correction threshold for each acceleration component via the threshold setting unit 12. The threshold setting unit 12 may be, for example, Figure 7A and Figure 7BIn this way, x1, y4, x2, y4, etc. are read for each acceleration component and P2, P4, P5 are plotted on a two-dimensional plane. The second correction threshold TH3 passing through P2, P4, P5 is set as the acceleration threshold. After that, the impact determination ECU 10 ends this time. Figure 8B Processing, return to Figure 8A Processing of S13.

[0074] If it is determined that the angle is greater than the angle threshold (S23: No), in S25, the impact determination ECU 10 sets the first correction threshold for each acceleration component via the threshold setting unit 12. The threshold setting unit 12 may be, for example, Figure 6A and Figure 6B In this way, x1, y3, x2, y2, etc. are read for each acceleration component and P2 and P3 are plotted on a two-dimensional plane. The first correction threshold TH2 passing through P2 and P3 is set as the acceleration threshold. After that, the impact determination ECU 10 ends this time. Figure 8B Processing, return to Figure 8A Processing of S13.

[0075] Return to Figure 8A In S13, the impact determination ECU 10 determines whether the acceleration is greater than the acceleration threshold value through the impact determination unit 13. The impact determination unit 13 compares, for example, the recognized acceleration of the host vehicle 50 with the acceleration threshold value set in S12. The impact determination unit 13 compares the recognized front-to-back component of the acceleration with the front-to-back component of the set acceleration threshold value. The impact determination unit 13 compares the recognized left-to-right component of the acceleration with the left-to-right component of the set acceleration threshold value. If the acceleration is greater than the acceleration threshold value for both the front-to-back and left-to-right components, the impact determination unit 13 determines the process of S13 as "yes". If the acceleration is less than the acceleration threshold value for either the front-to-back or left-to-right components, the impact determination unit 13 determines the process of S13 as "no".

[0076] In S14, the impact determination ECU 10 determines the impact through the impact determination unit 13. In S14, the impact determination unit 13 determines that the other vehicle has caused an impact of a certain degree or more on the host vehicle 50, and determines the impact (makes an impact determination). The impact determination ECU 10 can send an inflation control signal to the airbag actuator 3 to deploy the airbag device. After that, the impact determination ECU 10 ends this time. Figure 8A processing.

[0077] In the impact determination device 100 described above, the impact determination ECU 10, via the threshold setting unit 12, identifies the type of impact from another vehicle on the host vehicle 50 based on the detection results of the external sensor 2. Acceleration thresholds are set for each acceleration component according to the impact type. This allows the acceleration thresholds to be set based on the impact type based on the detection results of the external sensor 2. Therefore, compared to setting the acceleration threshold based solely on the impact type identified based on the detection results of the acceleration sensor, for example, impacts from another vehicle on the host vehicle 50 can be more appropriately determined. As a result, a system utilizing impact determination results can be implemented at a low cost while minimizing degradation in detection performance.

[0078] In the impact determination device 100, the threshold setting unit 12 identifies an offset collision of another vehicle against the host vehicle 50 as an impact type and sets the acceleration threshold for each acceleration component based on the offset amount of the offset collision. Thus, by setting the acceleration threshold for each acceleration component based on the offset amount, the accuracy of determining an impact of another vehicle against the host vehicle 50 can be improved.

[0079] While the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments. The present disclosure can be implemented in various forms by variously changing and improving the above-described embodiments as a representative example based on the knowledge of those skilled in the art.

[0080] In the above embodiment, the threshold setting unit 12 sets the acceleration threshold for each acceleration component based on the offset amount of the offset collision and the angle of the other vehicle relative to the host vehicle 50. However, the present invention is not limited to this example. For example, the threshold setting unit 12 may set the acceleration threshold for each acceleration component based on information such as the type of the other vehicle (i.e., the size and weight of the other vehicle), the relative speed of the other vehicle relative to the host vehicle 50, and the speed of the host vehicle 50.

[0081] In the above embodiment, the acceleration threshold is set for each acceleration component according to the offset amount of the offset collision, but this example may be omitted.

[0082] In the above embodiment, an example of deploying the airbag device is shown as a system using the result of the impact determination, but this example is not essential. The impact determination device 100 only needs to be able to determine at least an impact.

Claims

1. An impact determination device comprising: An acceleration sensor that detects acceleration including components in the vehicle's front-to-back and left-to-right directions; External sensors to detect objects around the vehicle; a threshold setting unit that sets a threshold for determining an impact caused by the object on the vehicle; and an impact determination unit that determines the impact when the acceleration is equal to or greater than the threshold value for each of the components, The threshold setting unit, identifying the impact form of the object on the vehicle based on the detection result of the external sensor, The threshold value is set for each of the components of the acceleration according to the impact form.

2. The impact determination device according to claim 1, The threshold setting unit, identifying an offset collision of the object with the vehicle as the impact form, The threshold value is set for each of the components of the acceleration according to the offset amount of the offset collision.

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