Anomaly detection device
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2024-12-04
- Publication Date
- 2026-06-16
Smart Images
Figure 2026097547000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an abnormality detection device.
Background Art
[0002] For example, Patent Document 1 describes a vehicle collision detection device that detects a collision with a pedestrian or the like. The vehicle collision detection device described in Patent Document 1 includes a detection tube member mounted in a groove formed in a bumper absorber within a bumper of a vehicle, a pressure sensor that detects the pressure within the hollow portion of the detection tube member, a collision detection unit that detects a collision of an object against the bumper based on the pressure detection result by the pressure sensor, a pressing member disposed within the groove that can switch between a non-pressing state in which the detection tube member is not pressed by an external signal and a pressing state in which the detection tube member is pressed, and an abnormality detection unit that detects an abnormality of the detection tube member based on the pressure detection result by the pressure sensor when the pressing member is in the pressing state.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In the conventional technology described above, when detecting an abnormality in the detection tube member based on the pressure sensor's detection value, it is necessary to press the detection tube member with an external signal. When the vehicle is in motion, the detection tube member may come out of the groove in the bumper absorber due to vehicle vibrations, etc. However, the abnormality of the detection tube member is not detected until it is pressed. Therefore, it is not possible to detect abnormalities in the detection tube member in real time. Consequently, until the detection tube member is pressed and an abnormality is detected, the abnormal state information of the detection tube member is not notified to the vehicle driver, and the vehicle continues to drive with the detection tube member in an abnormal state. As a result, it becomes difficult to properly detect collisions of objects with the bumper.
[0005] The object of the present invention is to provide an anomaly detection device that can detect anomalies in a collision detection sensor located at the front of a vehicle in real time. [Means for solving the problem]
[0006] (1) One aspect of the present invention is an abnormality detection device for detecting whether a collision detection sensor, which detects whether an object has collided with the front of a vehicle, has come out of a sensor housing provided on the front bumper of a vehicle, comprising: a contact detection unit for detecting whether or not there is contact with the collision detection sensor; a determination unit for determining whether the collision detection sensor is in an abnormal state of having come out of the sensor housing by determining whether or not the contact detection unit has continuously detected a state in which the contact detection unit and the collision detection sensor are not in contact for a predetermined period of time or longer; and a notification unit for notifying that an abnormal state exists when the determination unit has determined that the contact detection unit and the collision detection sensor have continuously detected a state in which they are not in contact for a predetermined period of time or longer.
[0007] (2) In (1) above, the front bumper has a bumper reinforcement, a bumper cover positioned in front of the bumper reinforcement, and a bumper absorber positioned between the bumper reinforcement and the bumper cover to absorb the load generated when an object collides with the bumper cover, and the sensor housing is provided on the bumper absorber so as to extend in the vehicle width direction and is a groove that opens on the rear end surface of the bumper absorber, and the contact detection unit may be positioned within the groove.
[0008] (3) In (2) above, the contact detection unit may be fixed to the bottom surface of the groove.
[0009] (4) In any of (1) to (3) above, if there are multiple contact detection units, the determination unit may determine that an abnormal state exists when it is determined that a state in which multiple contact detection units and the collision detection sensor are not in contact has been detected continuously for a specified period of time or longer. [Effects of the Invention]
[0010] According to the present invention, abnormalities in a collision detection sensor located at the front of a vehicle can be detected in real time. [Brief explanation of the drawing]
[0011] [Figure 1] This is a schematic diagram showing a collision detection system equipped with an anomaly detection device according to one embodiment of the present invention. [Figure 2] This diagram shows the external appearance of a collision detection sensor. [Figure 3] This is a cross-sectional view showing the front bumper together with the collision detection sensor and contact detection sensor. [Figure 4] This flowchart shows the procedure for abnormality detection and notification processing performed by the ECU. [Figure 5] As a comparative example, this cross-sectional view shows the normal and abnormal states of a collision detection sensor in the absence of a contact detection sensor. [Figure 6]This is a cross-sectional view showing the normal and abnormal states of a collision detection sensor when a contact detection sensor is present. [Modes for carrying out the invention]
[0012] Embodiments of the present invention will be described in detail below with reference to the drawings.
[0013] Figure 1 is a schematic diagram showing a collision detection system equipped with an anomaly detection device according to one embodiment of the present invention. In Figure 1, the collision detection system 1 is mounted on a vehicle 2 having a pop-up hood (PUH) function.
[0014] The pop-up hood is a safety device designed to mitigate the impact on a pedestrian in the event of a collision between vehicle 2 and the pedestrian. When vehicle 2 collides with a pedestrian, the pop-up hood lifts the rear portion of the vehicle's hood (bonnet), creating a gap between the hood and the components inside the engine compartment. The collision detection system 1 detects a collision between vehicle 2 and an object such as a pedestrian, and activates the pop-up hood according to the detection result.
[0015] The collision detection system 1 includes a collision detection sensor 3, a contact detection sensor 4, a PUH drive unit 5, a warning lamp 6, a display 7, and an ECU (Electronic Control Unit) 8.
[0016] The collision detection sensor 3 is a sensor that detects whether an object such as a pedestrian has collided with the front of the vehicle 2. As shown in Figure 2, the collision detection sensor 3 has a structure in which pressure sensors 12 are attached to both ends of a sealed hollow tube 11, and is referred to as a tube sensor. The pressure sensors 12 detect the pressure inside the hollow tube 11.
[0017] As shown in FIG. 3, the collision detection sensor 3 is attached to the front bumper 13 disposed at the front of the vehicle 2. The front bumper 13 has a bumper reinforcement 14, a bumper cover 15 disposed on the front side of the bumper reinforcement 14, and a bumper absorber 16 disposed between the bumper reinforcement 14 and the bumper cover 15.
[0018] The bumper absorber 16 is a foamed material (absorbent material) that absorbs energy by deforming upon collision with an object. The bumper absorber 16 is formed of a lightweight and highly impact-absorbent material such as, for example, foamed plastic or polypropylene. The bumper absorber 16 has a rear end face 16a that is an end face on the bumper reinforcement 14 side and a front end face 16b that is an end face on the bumper cover 15 side.
[0019] The bumper absorber 16 is provided with a groove portion 17 having a rectangular cross section that opens to the rear end face 16a. The groove portion 17 extends in the vehicle width direction (left - right direction) of the vehicle 2. The hollow tube 11 of the collision detection sensor 3 is fitted into the groove portion 17. The groove portion 17 forms a sensor housing portion in which the collision detection sensor 3 is housed.
[0020] Normally, as shown in FIG. 3(a), the hollow tube 11 housed in the groove portion 17 of the bumper absorber 16 is not deformed. In the normal state, the bumper reinforcement 14 and the bumper absorber 16 may be in contact with each other (see FIG. 3), or a gap may be provided between the bumper reinforcement 14 and the bumper absorber 16.
[0021] When the vehicle 2 collides with a pedestrian, as shown in FIG. 3(b), the bumper absorber 16 is pushed rearward of the vehicle 2 by the load generated during the collision, so that the hollow tube 11 housed in the groove portion 17 of the bumper absorber 16 is deformed and the pressure in the hollow tube 11 changes from the normal state.
[0022] The contact detection sensor 4 is a sensor (contact detection unit) that detects whether or not it is in contact with the collision detection sensor 3. The contact detection sensor 4 outputs a detection signal according to whether or not it is in contact with the collision detection sensor 3. As shown in Figure 3, the contact detection sensor 4 is located in the groove 17 of the bumper absorber 16. The contact detection sensor 4 is, for example, plate-shaped. The contact detection sensor 4 is fixed to the bottom surface 17a of the groove 17. The bottom surface 17a of the groove 17 is the surface on the front end surface 16b side of the groove 17. In other words, the bottom surface 17a of the groove 17 is the surface opposite to the opening of the groove 17.
[0023] There are multiple contact detection sensors 4. The contact detection sensors 4 are positioned at multiple locations where it is anticipated that the hollow tube 11 of the collision detection sensor 3 will disengage from the groove 17 of the bumper absorber 16.
[0024] For example, a tactile sensor or a piezoelectric film sensor can be used as the contact detection sensor 4. A tactile sensor detects physical contact, pressure, or vibration. A piezoelectric film sensor detects physical force (pressure or vibration, etc.) using the piezoelectric effect.
[0025] The PUH drive unit 5 drives the rear portion of the vehicle 2's hood to lift. The warning lamp 6 is a lamp that visually notifies the driver of abnormal information from the collision detection sensor 3 as an alarm. The display 7 has a display screen that visually displays the abnormal information from the collision detection sensor 3.
[0026] The ECU8 consists of a CPU, RAM, ROM, and input / output interfaces. For example, the ECU8 loads a program stored in ROM into RAM, and then the CPU executes the program loaded into RAM. The ECU8 also has a built-in timer.
[0027] The ECU8 includes a sensor information acquisition unit 20, a collision determination unit 21, a PUH control unit 22, an abnormality determination unit 23, and an abnormality notification unit 24.
[0028] The contact detection sensor 4, sensor information acquisition unit 20, abnormality determination unit 23, abnormality notification unit 24, warning lamp 6, and display 7 constitute the abnormality detection device 10 of this embodiment. The abnormality detection device 10 is a device that detects whether the collision detection sensor 3 has come out of the groove 17 (sensor housing) provided in the front bumper 13 of the vehicle 2.
[0029] The sensor information acquisition unit 20 acquires pressure information inside the hollow tube 11 detected by the pressure sensor 12 of the collision detection sensor 3, and information on whether or not there is contact between the contact detection sensor 4 and the collision detection sensor 3, which is detected by the multiple contact detection sensors 4.
[0030] The collision determination unit 21 determines whether the vehicle 2 has collided with an object such as a pedestrian, based on the pressure information inside the hollow tube 11 acquired by the sensor information acquisition unit 20. The collision determination unit 21 determines that the vehicle 2 has collided with an object if the pressure inside the hollow tube 11 exceeds a specified pressure.
[0031] When the collision determination unit 21 determines that the vehicle 2 has collided with an object, the PUH control unit 22 controls the PUH drive unit 5 so that the rear portion of the vehicle 2's hood is lifted.
[0032] The abnormality determination unit 23 determines whether the hollow tube 11 of the collision detection sensor 3 is in an abnormal state where it has come out of the groove 17 of the front bumper 13 by determining whether the state in which multiple contact detection sensors 4 and collision detection sensors 3 are not in contact has been continuously detected for a predetermined period of time or longer, based on the contact detection sensor 4 and collision detection sensor 3 contact detection sensor information acquired by the sensor information acquisition unit 20.
[0033] The abnormality determination unit 23 works in cooperation with the sensor information acquisition unit 20 to determine whether the collision detection sensor 3 is in an abnormal state where it has come out of the groove 17 of the front bumper 13, by determining whether or not a state in which the contact detection sensor 4 and the collision detection sensor 3 are not in contact has been detected continuously for a specified period of time or longer.
[0034] When the abnormality determination unit 23 determines that the collision detection sensor 3 is in an abnormal state, having disengaged from the groove 17 of the front bumper 13, the abnormality notification unit 24 controls the warning lamp 6 and the display 7 to notify that an abnormal state exists.
[0035] The abnormality notification unit 24, in cooperation with the warning lamp 6 and the display 7, is configured as a notification unit that notifies the system of an abnormal condition when the determination unit determines that the contact detection sensor 4 and the collision detection sensor 3 have been continuously in a state of not being in contact for a specified period of time or longer.
[0036] Figure 4 is a flowchart showing the procedure for abnormality detection and notification processing performed by the ECU8. This processing is performed by the sensor information acquisition unit 20, abnormality detection unit 23, and abnormality notification unit 24 of the ECU8.
[0037] This process starts when the ignition switch (IG switch), not shown in the diagram, is turned ON, and ends when the IG switch is turned OFF. When the IG switch is turned ON, power is supplied to the electrical system, including the ECU 8, collision detection sensor 3, contact detection sensor 4, PUH drive unit 5, warning lamp 6, and display 7.
[0038] In Figure 4, the ECU 8 first resets its built-in timer (procedure S101). Then, the timer starts measuring time. The ECU 8 also sets the contact flag to 0 (procedure S102). The contact flag is used to record whether or not there is contact between the contact detection sensor 4 and the collision detection sensor 3.
[0039] Next, the ECU8 determines whether the timer measurement time is shorter than a predetermined time T1 (procedure S103). If the ECU8 determines that the timer measurement time is shorter than the predetermined time T1, it determines whether the contact flag is 0 (procedure S104). The determination process in procedure S104 is performed for each contact detection sensor 4. If the ECU8 determines that the contact flag is 1 and not 0, it repeats procedure S103.
[0040] When the ECU8 determines that the contact flag is 0, it acquires the detection signal from the contact detection sensor 4 (procedure S105). Then, based on the detection signal from the contact detection sensor 4, the ECU8 determines whether or not there is contact between the contact detection sensor 4 and the collision detection sensor 3 (procedure S106). The determination process in procedure S106 is performed for each contact detection sensor 4.
[0041] If the ECU8 determines that there is contact between the contact detection sensor 4 and the collision detection sensor 3, it sets the contact flag to 1 (procedure S107) and repeats procedure S103. If the ECU8 determines that there is no contact between the contact detection sensor 4 and the collision detection sensor 3, it sets the contact flag to 0 (procedure S108) and repeats procedure S103.
[0042] If the ECU8 determines in step S103 that the timer measurement time is equal to or greater than the specified time T1, it determines whether the contact flag is 0 for all contact detection sensors 4 (step S109). If the ECU8 determines that the condition that the contact flag is 0 for all contact detection sensors 4 is not met, it repeats step S101.
[0043] When the ECU8 determines that the condition of having a contact flag of 0 is met for all contact detection sensors 4, it controls the warning lamp 6 and display 7 to notify that an abnormal condition has occurred (procedure S110), and then performs procedure S101 again.
[0044] Here, the sensor information acquisition unit 20 executes procedure S105. The abnormality determination unit 23 executes procedures S101 to S104 and S106 to S109. The abnormality notification unit 24 executes procedure S110.
[0045] In the collision detection system 1 described above, in order to accurately determine whether the vehicle 2 has collided with a pedestrian, it is necessary that the hollow tube 11 of the collision detection sensor 3 is properly housed in the groove 17 of the bumper absorber 16, as shown in Figure 3.
[0046] Incidentally, as shown in Figure 5, if the above-mentioned contact detection sensor 4 is not used, the following problems occur. That is, as shown in Figure 5(a), in the normal state in which the hollow tube 11 of the collision detection sensor 3 is housed in the groove 17 of the bumper absorber 16, when the vehicle 2 collides with a pedestrian, the hollow tube 11 deforms due to the load at the time of the collision as described above, and the collision between the vehicle 2 and the pedestrian is detected by the collision detection sensor 3.
[0047] However, as shown in Figure 5(b), if the hollow tube 11 of the collision detection sensor 3 detaches from the groove 17 of the bumper absorber 16 due to vibrations during vehicle 2's operation, the collision between vehicle 2 and pedestrian will not be detected by the collision detection sensor 3, even if vehicle 2 collides with a pedestrian. Therefore, the pop-up hood of vehicle 2 cannot be activated. Consequently, when the hollow tube 11 of the collision detection sensor 3 detaches from the groove 17 of the bumper absorber 16, it is necessary to reposition the hollow tube 11 into the groove 17, and therefore it is necessary to notify the user of the abnormality as soon as possible.
[0048] To address such challenges, in this embodiment, in the normal state where the hollow tube 11 of the collision detection sensor 3 is housed in the groove 17 of the bumper absorber 16, the contact detection sensor 4 and the collision detection sensor 3 are in contact, as shown in Figure 6(a). In this case, the contact detection sensor 4 detects contact with the collision detection sensor 3. Therefore, when the vehicle 2 collides with a pedestrian, the collision detection sensor 3 detects the collision between the vehicle 2 and the pedestrian, and the pop-up hood of the vehicle 2 is activated.
[0049] On the other hand, as shown in Figure 6(b), if the hollow tube 11 of the collision detection sensor 3 detaches from the groove 17 of the bumper absorber 16 due to vibrations during vehicle 2's operation, the contact detection sensor 4 and the collision detection sensor 3 become non-contact. In this case, the contact detection sensor 4 detects that there is no contact with the collision detection sensor 3. When the time during which the contact detection sensor 4 and the collision detection sensor 3 are detected as not in contact exceeds a specified time T1, it is determined that an abnormal condition has occurred where the hollow tube 11 of the collision detection sensor 3 has come out of the groove 17 of the bumper absorber 16. The user is then notified of this abnormal condition via the warning lamp 6 and the display 7.
[0050] As described above, according to this embodiment, a collision detection sensor 3, which detects whether an object has collided with the front of the vehicle 2, is housed in a groove 17 provided in the front bumper 13 of the vehicle 2. Contact detection sensor 4 also detects contact with the collision detection sensor 3. Then, by determining whether a state in which the contact detection sensor 4 and the collision detection sensor 3 are not in contact has been detected continuously for a specified time T1 or longer, it is determined whether the collision detection sensor 3 is in an abnormal state, having come out of the groove 17. When it is determined that a state in which the contact detection sensor 4 and the collision detection sensor 3 are not in contact has been detected continuously for a specified time T1 or longer, a notification that an abnormal state exists is sent. Therefore, while the vehicle 2 is in motion, it is possible to determine in real time whether the collision detection sensor 3 is in an abnormal state, having come out of the groove 17 of the front bumper 13 due to vibrations of the vehicle 2, etc. In this way, abnormal detection of the collision detection sensor 3 located at the front of the vehicle 2 is performed in real time. As a result, the driver of the vehicle 2 can immediately know if the collision detection sensor 3 is in an abnormal state. If the collision detection sensor 3 is in an abnormal state, the collision detection sensor 3 is housed in the groove 17 of the front bumper 13. This prevents the vehicle 2 from continuing to drive while the collision detection sensor 3 is in an abnormal state, and enables proper detection of collisions with objects to the front of the vehicle 2.
[0051] Furthermore, in this embodiment, by arranging the contact detection sensor 4 within the groove 17 of the bumper absorber 16, it is possible to determine whether the collision detection sensor 3 is in an abnormal state, having come out of the groove 17 of the bumper absorber 16, with a simple structure.
[0052] Furthermore, in this embodiment, by fixing the contact detection sensor 4 to the bottom surface 17a of the groove 17 of the bumper absorber 16, it becomes easier to determine whether the collision detection sensor 3 is in an abnormal state, having come out of the groove 17 of the bumper absorber 16.
[0053] Furthermore, in this embodiment, when it is determined that a state in which the multiple contact detection sensors 4 and the collision detection sensor 3 are not in contact is detected for a specified time T1 or longer, it is determined that this is an abnormal state. Therefore, when at least one of the multiple contact detection sensors 4 is in contact with the collision detection sensor 3, it is determined that the collision detection sensor 3 is in a normal state, housed in the groove 17 of the front bumper 13. Accordingly, this is effective when there are multiple locations on the front bumper 13 where the collision detection sensor 3 is likely to come out of the groove 17.
[0054] It should be noted that the present invention is not limited to the above embodiments. For example, in the above embodiments, there are multiple contact detection sensors 4, but the invention is not limited to any particular form, and there may be only one contact detection sensor 4. In this case, the contact detection sensor 4 may be placed at the location where the hollow tube 11 of the collision detection sensor 3 is most likely to come off the groove 17 of the bumper absorber 16.
[0055] Furthermore, in the above embodiment, the contact detection sensor 4 is fixed to the bottom surface 17a of the groove 17 of the bumper absorber 16, but it is not limited to such a configuration. The contact detection sensor 4 can be placed within the groove 17 of the bumper absorber 16.
[0056] Furthermore, in the above embodiment, the contact detection sensor 4 is arranged in the groove 17 of the bumper absorber 16, but the embodiment is not limited to this configuration. For example, the bumper absorber 16 may be provided with a hole such as a through hole that serves as a sensor housing. In this case, the contact detection sensor 4 may be arranged in the hole of the bumper absorber 16.
[0057] Furthermore, although the abnormality detection device 10 of the above embodiment is applied to a collision detection system 1 mounted on a vehicle 2 having a pop-up hood (PUH) function, the present invention can also be applied to a collision detection system mounted on a vehicle that does not have a PUH function, for example. [Explanation of Symbols]
[0058] 2...Vehicle, 3...Collision detection sensor, 4...Contact detection sensor (contact detection unit), 6...Warning lamp (notification unit), 7...Display (notification unit), 13...Front bumper, 14...Bumper reinforcement, 15...Bumper cover, 16...Bumper absorber, 16a...Rear end surface, 17...Groove (sensor housing), 17a...Bottom surface, 20...Sensor information acquisition unit (determination unit), 23...Anomaly determination unit (determination unit), 24...Anomaly notification unit (notification unit), T1...Specified time.
Claims
1. An anomaly detection device that detects whether a collision detection sensor, which detects whether an object has collided with the front of a vehicle, has come out of the sensor housing provided on the front bumper of the vehicle, A contact detection unit that detects whether or not contact has occurred with the collision detection sensor, A determination unit determines whether the collision detection sensor is in an abnormal state where it has come out of the sensor housing by determining whether the contact detection unit has continuously detected a state in which the contact detection unit and the collision detection sensor are not in contact for a predetermined period of time or longer, An abnormality detection device comprising: a determination unit that determines that the contact detection unit and the collision detection sensor have been in a state of not being in contact for a specified period of time or longer, and a notification unit that notifies that an abnormal state exists.
2. The front bumper comprises a bumper reinforcement, a bumper cover positioned in front of the bumper reinforcement, and a bumper absorber positioned between the bumper reinforcement and the bumper cover to absorb the load generated when an object collides with the bumper cover. The sensor housing portion is provided on the bumper absorber so as to extend in the vehicle width direction and is a groove portion that opens on the rear end surface of the bumper absorber. The abnormality detection device according to claim 1, wherein the contact detection unit is arranged within the groove.
3. The abnormality detection device according to claim 2, wherein the contact detection unit is fixed to the bottom surface of the groove.
4. The number of the aforementioned contact detection units is multiple. The abnormality detection device according to claim 1, wherein the determination unit determines that an abnormal state exists when it is determined that a state in which a plurality of contact detection units and the collision detection sensor are not in contact has been continuously detected for a specified time or longer.