JP2012176688A - Collision protection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a collision protection device that increases the degree of freedom in arrangement of an acceleration sensor for detecting acceleration in a vertical direction of a vehicle in comparison with a conventional technique, can use an acceleration sensor with a lower environmental resistance and further lowers repair costs when a front bumper is damaged.SOLUTION: The collision protection device includes: a first detector 1 that is arranged in a front bumper 6a of the vehicle 6 and an area other than a rear part A beyond an axle of rear wheels and detects the acceleration in a vertical direction of the vehicle 6; second detectors 2a, 2b, 2c that detect the acceleration in a longitudinal or lateral direction of the vehicle 6; a pedestrian protector 3 that protects a collision object with; and an ECU 4 that actuates the pedestrian protector 3 based on a detection results of the first detector 1 and the second detectors 2a, 2b, 2c.

Description

  The present invention relates to an impacted body protecting apparatus that detects an acceleration in a vertical direction of a vehicle and an acceleration in a longitudinal direction or a lateral direction of the vehicle to protect the impacted body.

Patent Document 1 discloses a collision detection device in which an acceleration sensor that detects a collision with a pedestrian and another acceleration sensor that detects acceleration in the vertical direction of a vehicle is provided on a front bumper.
By providing the acceleration sensor on the front bumper, it is possible to detect a collision with a pedestrian and protect the pedestrian.

JP-T-2006-521947

  However, in the collision detection device according to Patent Document 1, since the arrangement of the acceleration sensor that detects the acceleration in the vertical direction is restricted by the front bumper, the acceleration sensor is required to have environmental resistance characteristics, and when the front bumper is damaged. There was a problem that the repair cost was high.

  As a result of intensive studies, the inventor of the present application arranges an acceleration sensor that detects the acceleration in the vertical direction of the vehicle in a portion excluding the rear portion of the front bumper and the axle portion of the rear wheel, and executes a required calculation process. The present inventors have found the fact that it is possible to discriminate between a collision with a pedestrian and a vibration caused by running on a rough road, and it is possible to more reliably detect a collision with a pedestrian.

  The present invention has been made in view of such circumstances, and an object of the present invention is to increase the degree of freedom of arrangement of an acceleration sensor that detects acceleration in the vertical direction of a vehicle, and to have lower environmental resistance characteristics than the conventional technology. Another object of the present invention is to provide a collision object protection device that can be handled by an acceleration sensor and that also reduces the repair cost when the front bumper is damaged.

  A collision object protection device according to the present invention protects a collision object by a first detection unit that detects vertical acceleration of the vehicle, a second detection unit that detects longitudinal or lateral acceleration of the vehicle, and the like. And a protection unit that operates based on detection results of the first detection unit and the second detection unit. The first detection unit includes a front bumper and a rear bumper of the vehicle. It is arrange | positioned in the site | part except a rear part rather than the axle part of a wheel.

  In the present invention, the first detection unit that detects the acceleration in the vertical direction of the vehicle is arranged at a portion excluding the rear part from the front bumper of the vehicle and the axle part of the rear wheel. Therefore, the environmental resistance required for the first detector is lower than when the first detector is arranged on the front bumper.

  The collision object protection device according to the present invention is characterized in that the first detection unit is disposed between a front bumper and an axle portion of a rear wheel in the front-rear direction of the vehicle.

  In the present invention, the first detection unit is arranged between the front bumper and the axle portion of the rear wheel in the longitudinal direction of the vehicle. Therefore, the environmental resistance required for the first detection unit can be further reduced as compared with the case where the first detection unit is arranged in another part.

  The collision object protection device according to the present invention is characterized in that the second detection unit is arranged in a front bumper of the vehicle.

  In the present invention, the second detector for detecting the longitudinal acceleration of the vehicle is arranged on the front bumper of the vehicle. Therefore, it is possible to detect the collision of the collision object more accurately. Unlike the first detection unit that detects the vertical acceleration of the vehicle, the second detection unit that detects the longitudinal acceleration of the vehicle is disposed on the front bumper of the vehicle from the viewpoint of collision object detection accuracy. Is preferred.

  The collision object protection device according to the present invention is configured to determine whether the acceleration detected by the first detection unit is equal to or higher than a first threshold, and the acceleration detected by the second detection unit is a second value. Means for determining whether or not the threshold value is equal to or greater than a threshold value, wherein the protection unit has an acceleration detected by the first detection unit that is less than a first threshold value and an acceleration detected by the second detection unit is a first value. If it is 2 or more thresholds, it is configured to operate.

In the present invention, it is determined whether or not the acceleration detected by the first detection unit is greater than or equal to a first threshold value. The vertical acceleration of the vehicle increases when traveling on a rough road, but does not increase when the vehicle collides with a collision target. Further, it is determined whether or not the acceleration detected by the second detection unit is equal to or greater than a second threshold value. The acceleration in the longitudinal direction of the vehicle increases when the vehicle collides with a collision object or travels on a rough road. Therefore, the protection unit is configured to operate when the acceleration detected by the first detection unit is less than the first threshold and the acceleration detected by the second detection unit is greater than or equal to the second threshold.
Therefore, the protection unit operates at the time of collision with the collision target and does not operate even when it receives acceleration in the front-rear direction when traveling on a rough road.
In addition, since the first detection unit can discriminate between a collision with a pedestrian and traveling on a rough road, the second threshold value can be set low, and in this sense, collision detection accuracy with a pedestrian is improved. It is possible to make it.

  The collision object protection device according to the present invention includes a timing unit that starts timing when it is determined that the acceleration detected by the first detection unit is equal to or greater than a first threshold, and the protection unit includes the second unit. When the acceleration detected by the detection unit is equal to or greater than a second threshold value and the timekeeping unit times a predetermined time or longer, the acceleration is detected.

In the present invention, when it is determined that the acceleration detected by the first detection unit is greater than or equal to the first threshold value, the timer unit starts timing. The protection unit operates when the acceleration detected by the second detection unit is equal to or greater than the second threshold value and the timing unit counts a predetermined time or more.
Therefore, the protection unit operates at the time of collision with the collision target and does not operate even when it receives acceleration in the front-rear direction when traveling on a rough road.

  In the collision object protection device according to the present invention, before the time measuring unit counts the predetermined time, the acceleration detected by the first detection unit becomes less than the first threshold value and again becomes the first threshold value or more. In this case, the timekeeping unit is reset to start timekeeping.

  In the present invention, when the acceleration in the vertical direction of the vehicle becomes less than the first threshold value and rises to the first threshold value or more again before the time measuring unit times the predetermined time, the time measuring unit is reset and timed again. Is configured to start over. That is, it is configured to continue timing as if the rough road is continuing. Therefore, even when the rough road travel continues, the protection unit does not malfunction due to vibration caused by the rough road travel.

  The collision object protection device according to the present invention includes a timing unit that starts timing when the acceleration detected by the first detection unit changes from the first threshold value to less than the first threshold value, and the protection unit includes: The acceleration detected by the second detection unit is greater than or equal to a second threshold value, and the operation is performed when the timekeeping unit times more than a predetermined time.

  In the present invention, when the acceleration in the vertical direction of the vehicle becomes equal to or higher than the first threshold value and then becomes lower than the first threshold value, the time measuring unit starts measuring time. The operation of the protection unit is limited until the timing unit finishes counting the predetermined time. In other words, even if the vertical acceleration of the vehicle is less than the first threshold value, there is a risk that abnormal longitudinal acceleration due to running on a rough road may occur for a certain period of time. Restrict. Therefore, it is possible to more reliably prevent malfunction of the protection unit when traveling on a rough road.

  The collision object protection device according to the present invention includes means for determining whether or not the acceleration detected by the second detection unit is greater than or equal to a third threshold value that is greater than a second threshold value. When the acceleration detected by the two detectors is greater than or equal to a third threshold value, the sensor is operated regardless of the detection result of the first detector.

In the present invention, it is determined whether or not the acceleration detected by the second detection unit is equal to or greater than a third threshold value that is greater than the second threshold value. When the acceleration detected by the second detection unit is equal to or greater than the third threshold, the protection unit operates regardless of the detection result of the first detection unit, assuming that an unforeseen situation different from when traveling on a rough road has occurred. .
Therefore, even if an unexpected situation occurs that causes a vertical acceleration due to a collision with the colliding object and it is erroneously determined that the road is bad, the protection unit operates and protects the colliding object. To do.

  According to the present invention, the degree of freedom of arrangement of the acceleration sensor for detecting the acceleration in the vertical direction of the vehicle is increased as compared with the prior art, and it can be handled by the acceleration sensor having lower environmental resistance characteristics. Further, when the front bumper is broken Repair costs can also be reduced. In addition, since the movement of the vehicle itself can be detected more appropriately than when the vertical acceleration sensor is incorporated in the bumper, the detection performance of the rough road is improved.

It is the sectional side view which showed one structural example of the to-be-collised object protection apparatus which concerns on this Embodiment. It is the flowchart which showed the process sequence of ECU which concerns on this Embodiment. It is the graph which showed the time change of the acceleration of the up-and-down and the direction of order when a vehicle collides with a pedestrian. It is the graph which showed the time change of the acceleration of the up-and-down and the front-and-back direction when a vehicle gets on a level difference. 10 is a flowchart showing a processing procedure of an ECU according to Modification 1. 10 is a graph for explaining the processing contents of an ECU according to Modification 1; 10 is a flowchart showing a processing procedure of an ECU according to Modification 2. 10 is a graph for explaining the processing contents of an ECU according to Modification 2. 10 is a flowchart showing a processing procedure of an ECU according to Modification 3. 10 is a graph for explaining processing contents of an ECU according to Modification 3. 10 is a flowchart showing a processing procedure of an ECU according to Modification 4. 10 is a graph for explaining the processing contents of an ECU according to Modification 4. 10 is a flowchart showing a processing procedure of an ECU according to Modification 5. 10 is a flowchart showing a processing procedure of an ECU according to Modification 5. 10 is a graph for explaining the processing contents of an ECU according to Modification 5.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.
FIG. 1 is a side sectional view showing an example of the configuration of a collision object protection apparatus according to the present embodiment. The collision object protection apparatus according to the embodiment of the present invention is mounted on a vehicle 6, and includes a first detection unit 1 that detects acceleration in the vertical direction of the vehicle 6, and acceleration in the front-rear direction or lateral direction of the vehicle 6. Second detection units 2a, 2b, and 2c that detect pedestrians, a pedestrian protection unit 3 (protection unit) that protects an impacted body such as a pedestrian, and an ECU 4 that includes a timekeeping unit 5 therein.

The first detection unit 1 is a portion excluding the rear portion A from the front bumper 6a and the rear wheel axle portion of the vehicle 6, for example, between the front bumper 6a and the rear bumper 6b in the front-rear direction, that is, substantially at the center of the vehicle 6. It is arranged in the department. Specifically, the first detection unit 1 may be arranged at a place where there is a certain degree of rigidity, such as above the center tunnel and below the center console, and where the movement of the vehicle is appropriately transmitted. Further, as much as possible, it is preferable that the first detection unit 1 is arranged at a substantially central portion in the lateral direction of the vehicle 6. When the first detection unit 1 is arranged at a substantially central portion in the lateral direction of the vehicle 6, even when only one wheel rides on the step, the vertical detection can be detected by one first detection unit 1. Is possible. When the 1st detection part 1 is unevenly distributed to one of the horizontal direction of the vehicle 6, it is good to arrange | position two 1st detection parts 1 to a horizontal direction both sides. This is because the acceleration in the vertical direction when only one wheel has climbed the step can be detected by any one of the first detection units 1.
The first detection unit 1 is, for example, a capacitive acceleration sensor, and outputs a detected signal, that is, a signal indicating the vertical acceleration of the vehicle 6 to the ECU 4. The first detection unit 1 has a movable part that is displaced by the acceleration of the first detection unit 1, and detects a change in capacitance due to the displacement of the movable part as an acceleration. The first detection unit 1 is not limited to the capacitance type, and may employ other semiconductor type, optical type, mechanical type acceleration sensors such as a piezoresistive type. The connection between the first detection unit 1 and the ECU 4 may be either wired or wireless.

  The second detection units 2a, 2b, and 2c are disposed on both sides in the lateral direction of the front bumper 6a of the vehicle 6 and substantially in the lateral direction. The second detection units 2a, 2b, and 2c output the detected signal, that is, a signal indicating the longitudinal acceleration of the vehicle 6 to the ECU 4. The structures of the second detection units 2a, 2b, and 2c are basically the same as those of the first detection unit 1.

The pedestrian protection unit 3 supports, for example, the rear end portion of the hood of the vehicle 6 so as to be raised, and stores a bag-like airbag folded under the rear end of the hood. And the pedestrian protection part 3 supplies gas, expand | deploys an airbag in the case of a collision with a pedestrian, and lifts the rear-end part of food | hood with this airbag. When a pedestrian who is lifted up collides with the hood due to a collision with the vehicle, the impact applied to the pedestrian is mitigated by the hood and the airbag under the hood.
As another example, the pedestrian protection unit 3 is a device that relieves an impact applied to a pedestrian that collides with the vehicle 6, and operates according to a control signal from the ECU 4. The pedestrian protection unit 3 includes a so-called pedestrian protection airbag that reduces the impact on the pedestrian.
For example, the pedestrian protection unit 3 has an airbag folded on the front bumper 6a. The pedestrian protection unit 3 supplies gas and deploys the airbag forward and obliquely downward of the vehicle 6 in the event of a collision with the pedestrian, so that the pedestrian's legs are caught in the front bumper 6a, etc. Can prevent accidents.
The pedestrian protection unit 3 described above is an example, and any device that protects a pedestrian that collides with the vehicle 6 is included in the pedestrian protection unit 3.

  The ECU 4 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores a program for operating a pedestrian protection unit by detecting a pedestrian collision, and a RAM (Random Access Memory) for temporarily storing data. And a microprocessor having an input unit to which signals from the first detection unit 1 and the second detection units 2a, 2b, and 2c are input, an output unit for outputting a control signal to the pedestrian protection unit 3, and the like. In addition, the EEPROM stores a first threshold value for determining an impact when traveling on a rough road and a second threshold value for determining a collision with a pedestrian. The CPU of the ECU 4 executes a process described later based on a signal input from the input unit, and detects a collision with a pedestrian. When the CPU detects a collision with a pedestrian, the CPU outputs a control signal to the pedestrian protection unit 3 via the output unit to operate the pedestrian protection unit 3.

  The time measuring unit 5 is a program executed in the CPU that measures time, starts time measurement in accordance with a control command from the ECU 4, and outputs a time measurement result to the ECU 4 in response to a request from the ECU 4.

  FIG. 2 is a flowchart showing a processing procedure of the ECU 4 according to the present embodiment. ECU4 detects the acceleration of the up-down direction of the vehicle 6 in the 1st detection part 1 (step S11). Next, the ECU 4 determines whether or not the vertical acceleration detected by the first detection unit 1 is greater than or equal to the first threshold value (step S12). If it is determined that the vertical acceleration is greater than or equal to the first threshold (step S12: YES), the ECU 4 returns to step S11 and executes this loop again.

  When it is determined that the vertical acceleration is less than the first threshold (step S12: NO), the ECU 4 detects the longitudinal acceleration of the vehicle 6 by the second detection units 2a, 2b, and 2c (step S13). ), It is determined whether or not the longitudinal acceleration of the vehicle 6 detected by the second detectors 2a, 2b, and 2c is greater than or equal to a second threshold (step S14). When the longitudinal acceleration is less than the second threshold (step S14: NO), the ECU 4 returns to step S11 and executes this loop again.

  When the longitudinal acceleration is equal to or greater than the second threshold (step S14: YES), the ECU 4 operates the pedestrian protection unit 3 (step S15) and ends the process. ECU4 is controlling the operation | movement of the pedestrian protection part 3 by performing the above process.

  FIG. 3 is a graph showing temporal changes in vertical and longitudinal acceleration when the vehicle 6 collides with a pedestrian. FIG. 4 is a temporal change in vertical and longitudinal acceleration when the vehicle 6 rides on a step. It is the graph which showed. FIG. 3 and FIG. 4 schematically show the results of an actual experiment conducted with the first detection unit 1 disposed in the substantially central portion of the vehicle 6 and the second detection units 2a, 2b, and 2c disposed in the front bumper 6a. It is. 3A and 4A, the horizontal axis indicates time, and the vertical axis indicates the acceleration in the vertical direction of the vehicle 6 detected by the first detection unit 1. Similarly, in FIGS. 3B and 4B, the horizontal axis represents time, and the vertical axis represents the longitudinal acceleration of the vehicle 6 detected by the second detectors 2a, 2b, and 2c.

As shown in FIG. 3, when colliding with a pedestrian, acceleration in the front-rear direction is generated, but large acceleration in the vertical direction is not generated. On the other hand, as shown in FIG. 4, when traveling on a rough road, vertical acceleration occurs before the longitudinal acceleration occurs.
Conventionally, in order to determine collision with a pedestrian and traveling on a rough road, it has been considered that the first detection unit 1 that detects acceleration in the vertical direction needs to be disposed on the front bumper 6a. It has been found that even when the first detection unit 1 is arranged at a substantially central portion of the vehicle 6, it is possible to determine a collision with a pedestrian as shown in FIGS.

Therefore, by determining whether the acceleration in the vertical direction is equal to or greater than the first threshold, it is possible to determine whether the acceleration in the front-rear direction is due to a collision with a pedestrian or traveling on a rough road. it can.
When the 1st detection part 1 is arrange | positioned at a bumper, when a bumper itself carries out an unexpected deformation | transformation and a motion, it may detect it accidentally. In the present invention, since the first detection unit 1 is directly installed in the portion surrounded by the vehicle body, the true movement of the vehicle body can be detected. Therefore, it is possible to improve the bad road detection performance.

  In the collision object protection device according to the present embodiment configured as described above, the first detection unit 1 having lower environmental resistance characteristics than the case where the first detection unit 1 is disposed on the front bumper 6a. Further, the repair cost when the front bumper 6a is broken can be reduced.

  Moreover, since the collision with the pedestrian and the running on the rough road can be discriminated by the vertical acceleration detected by the first detection unit 1, the second threshold can be set low. The collision detection accuracy can be improved. That is, it is possible to shorten the time until the collision detection of the pedestrian while maintaining the robustness against the rough road.

  Furthermore, by arranging the second detectors 2a, 2b, 2c on the front bumper 6a, the detection accuracy for the longitudinal acceleration of the vehicle 6 generated at the time of a collision with the pedestrian is improved, and the pedestrian can be detected more reliably can do.

  Furthermore, when another ECU that needs to detect the acceleration in the vertical direction of the vehicle 6 is disposed at a substantially central portion of the vehicle 6, the ECU 4 according to the present embodiment and the other ECUs The detection unit 1 can be shared, and the cost can be reduced. For example, since the airbag ECU needs to detect acceleration in the vertical direction for rollover or the like, the ECU 4 and the airbag ECU can share the first detection unit 1.

  In the embodiment, the example in which the first detection unit 1 is disposed in the substantially central portion of the vehicle 6 has been described. However, the first detection unit 1 may be provided in a portion excluding the rear portion A from the front bumper 6a and the axle portion of the rear wheel. . When the vehicle 6 travels on a rough road such as riding on a step, the vehicle 6 rotates up and down around the axle portion of the rear wheel. The present invention can be realized by providing the first detection unit 1 in a portion excluding the front bumper 6a and the rear portion A of the axle portion of the rear wheel.

(Modification 1)
FIG. 5 is a flowchart showing a processing procedure of the ECU 4 according to the first modification. The ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S31), and determines whether the vertical acceleration detected by the first detection unit 1 is equal to or greater than a first threshold value. Determination is made (step S32).

  When it is determined that the vertical acceleration is less than the first threshold value (step S32: NO), the ECU 4 detects the longitudinal acceleration of the vehicle 6 using the second detection units 2a, 2b, and 2c (step S33). ), It is determined whether or not the longitudinal acceleration of the vehicle 6 detected by the second detectors 2a, 2b, and 2c is greater than or equal to a second threshold (step S34). When the acceleration in the front-rear direction is less than the second threshold (step S34: NO), the ECU 4 returns to step S31 and executes this loop again.

  When the acceleration in the front-rear direction is equal to or greater than the second threshold (step S34: YES), the ECU 4 operates the pedestrian protection unit 3 and ends the process.

  When it is determined that the vertical acceleration is greater than or equal to the first threshold (step S32: YES), the ECU 4 causes the time measuring unit 5 to start measuring time (step S36). Then, the ECU 4 determines whether or not the time measured by the time measuring unit 5 has passed the predetermined time T1 (step S37). The predetermined time T1 is, for example, several milliseconds to several tens of milliseconds, and is stored in the EEPROM of the ECU 4. When it is determined that the predetermined time T1 has not elapsed (step S37: NO), the ECU 4 returns the process to step S37. When it is determined that the predetermined time T1 has elapsed (step S37: YES), the ECU 4 returns the process to step S31. The ECU 4 controls the operation of the pedestrian protection unit 3 by repeatedly executing the above processing.

  FIG. 6 is a graph for explaining the processing content of the ECU 4 according to the first modification. FIG. 6A shows the acceleration change in the vertical direction of the vehicle 6, and FIG. 6B shows the acceleration change in the front-rear direction of the vehicle 6. FIG. 6C shows the timing state of the timing unit 5. In the first modification, pedestrian detection is performed as a period during which a shock is generated on a rough road during a period indicated by hatching, that is, during a predetermined time T1 from when the vertical acceleration exceeds the first threshold. Is configured to not. That is, during the hatched period, as shown in FIG. 6B, even if the acceleration in the front-rear direction of the vehicle 6 exceeds the second threshold, it is not determined that a collision with a pedestrian has occurred. Yes. When the predetermined time T1 has elapsed from when the vertical acceleration exceeds the first threshold, the detection of the pedestrian is resumed, and when the longitudinal acceleration of the vehicle 6 exceeds the second threshold, It is determined that a collision has occurred.

  In the to-be-collised object protection device according to the modified example 1, as in the embodiment, the first detection unit 1 having lower environmental resistance characteristics than the case where the first detection unit 1 is disposed on the front bumper 6a. Furthermore, the repair cost when the front bumper 6a is damaged can be reduced.

  In addition, while the acceleration in the vertical direction exceeds the first threshold and during the predetermined time T1, the configuration is such that the longitudinal acceleration detection of the vehicle 6 and the collision determination process with the pedestrian are not executed. Continues to take data for other controls, recording, etc., and filter processing.

(Modification 2)
FIG. 7 is a flowchart showing a processing procedure of the ECU 4 according to the second modification. The ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S51), and determines whether the vertical acceleration detected by the first detection unit 1 is equal to or greater than a first threshold value. Determination is made (step S52).

  When it is determined that the vertical acceleration is less than the first threshold (step S52: NO), the ECU 4 detects the longitudinal acceleration of the vehicle 6 by the second detection units 2a, 2b, and 2c (step S53). ), It is determined whether or not the longitudinal acceleration of the vehicle 6 detected by the second detectors 2a, 2b, and 2c is greater than or equal to a second threshold value (step S54). If the longitudinal acceleration is less than the second threshold (step S54: NO), the ECU 4 returns to step S51 and executes the loop again.

  If the longitudinal acceleration is equal to or greater than the second threshold (step S54: YES), the ECU 4 outputs a control signal to the pedestrian protection unit 3 to operate the pedestrian protection unit 3 (step S55) and process Finish.

  When it is determined in step S52 that the vertical acceleration is greater than or equal to the first threshold (step S52: YES), the ECU 4 causes the time measuring unit 5 to start measuring time (step S56). Then, the ECU 4 determines whether or not the time measured by the time measuring unit 5 has passed the predetermined time T1 (step S57). If it is determined that the predetermined time T1 has elapsed (step S57: YES), the ECU 4 returns the process to step S51.

  When it is determined that the predetermined time T1 has not elapsed (step S57: NO), the ECU 4 detects acceleration in the front-rear direction of the vehicle 6 using the second detection units 2a, 2b, and 2c (step S58). Next, the ECU 4 determines whether or not the longitudinal acceleration detected by the second detectors 2a, 2b, and 2c is greater than or equal to a third threshold (step S59). The third threshold value is larger than the second threshold value, and the EEPROM of the ECU 4 stores the third threshold value. If it is determined that the longitudinal acceleration is less than the third threshold (step S59: NO), the ECU 4 returns the process to step S57. If it is determined that the longitudinal acceleration is greater than or equal to the third threshold value (step S59: YES), the ECU 4 operates the pedestrian protection unit 3 (step S55) and ends the process. The ECU 4 controls the operation of the pedestrian protection unit 3 by repeatedly executing the above processing.

  FIG. 8 is a graph for explaining the processing content of the ECU 4 according to the second modification. FIG. 8A shows the acceleration change in the vertical direction of the vehicle 6, and FIG. 8B shows the acceleration change in the front-rear direction of the vehicle 6. In the second modification, even if the vertical acceleration exceeds the first threshold, if there is a strong impact such that the longitudinal acceleration of the vehicle 6 exceeds the third threshold, the collision with the pedestrian will occur. It determines with having generate | occur | produced and it is comprised so that the pedestrian protection part 3 may be operated.

  In the collision object protection device according to the modified example 2, even if an unexpected situation different from that on a rough road occurs and the vertical acceleration exceeds the first threshold, pedestrian protection is performed. The part 3 can be operated and a pedestrian can be protected.

(Modification 3)
FIG. 9 is a flowchart showing a processing procedure of the ECU 4 according to the third modification. The ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S71), and determines whether the vertical acceleration detected by the first detection unit 1 is equal to or greater than a first threshold value. Determination is made (step S72).

  When it is determined that the vertical acceleration is less than the first threshold (step S72: NO), the ECU 4 detects the longitudinal acceleration of the vehicle 6 using the second detection units 2a, 2b, and 2c (step S73). ), It is determined whether or not the longitudinal acceleration of the vehicle 6 detected by the second detectors 2a, 2b, and 2c is greater than or equal to a second threshold (step S74). When the acceleration in the front-rear direction is less than the second threshold (step S74: NO), the ECU 4 returns to step S71 and executes the loop again.

  When the longitudinal acceleration is equal to or greater than the second threshold (step S74: YES), the ECU 4 operates the pedestrian protection unit 3 by outputting a control signal to the pedestrian protection unit 3 (step S75), and processing Finish.

  When it is determined in step S72 that the vertical acceleration is greater than or equal to the first threshold (step S72: YES), the ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S76). Then, it is determined whether or not the vertical acceleration detected by the first detection unit 1 is less than the first threshold value (step S77).

  When it is determined that the vertical acceleration detected by the first detection unit 1 is greater than or equal to the first threshold value (step S77: NO), the ECU 4 uses the second detection units 2a, 2b, and 2c to move the vehicle 6 back and forth. Directional acceleration is detected (step S78). Next, the ECU 4 determines whether or not the longitudinal acceleration detected by the second detectors 2a, 2b, and 2c is greater than or equal to a third threshold value (step S79). The third threshold value is the same value as in the second modification, and the EEPROM of the ECU 4 stores the third threshold value. If it is determined that the longitudinal acceleration is less than the third threshold (step S79: NO), the ECU 4 returns the process to step S76. If it is determined that the longitudinal acceleration is greater than or equal to the third threshold (step S79: YES), the ECU 4 operates the pedestrian protection unit 3 (step S75) and ends the process.

  When it is determined that the vertical acceleration is less than the first threshold (step S77: YES), the ECU 4 causes the time measuring unit 5 to start measuring time (step S80). Then, the ECU 4 determines whether or not the time measured by the time measuring unit 5 has passed the predetermined time T2 (step S81). When it is determined that the predetermined time T2 has elapsed (step S81: YES), the ECU 4 returns the process to step S71.

  When it is determined that the predetermined time T2 has not elapsed (step S81: NO), the ECU 4 detects the acceleration in the front-rear direction of the vehicle 6 using the second detection units 2a, 2b, and 2c (step S82). Next, the ECU 4 determines whether or not the longitudinal acceleration detected by the second detectors 2a, 2b, and 2c is equal to or greater than a third threshold (step S83). If it is determined that the longitudinal acceleration is less than the third threshold (step S83: NO), the ECU 4 returns the process to step S81. If it is determined that the longitudinal acceleration is greater than or equal to the third threshold (step S83: YES), the ECU 4 operates the pedestrian protection unit 3 (step S75) and ends the process. ECU4 is controlling the operation | movement of the pedestrian protection part 3 by performing the above process.

FIG. 10 is a graph for explaining the processing contents of the ECU 4 according to the third modification. FIG. 10A shows the acceleration change in the vertical direction of the vehicle 6, and FIG. 10B shows the timekeeping state of the timekeeping unit 5. In the modification 3, the period shown by hatching is a period in which an impact occurs when traveling on a rough road so that pedestrian detection is not performed. In the third modification, when the vertical acceleration exceeds the first threshold, the ECU 4 determines that the vehicle is traveling on a rough road, and even if the front-rear acceleration exceeds the second threshold, the pedestrian The protection unit 3 is not operated. Specifically, when the acceleration in the vertical direction exceeds the first threshold, the timer unit 5 enters a timing start waiting state, starts timing when the acceleration falls below the first threshold, and sets a predetermined time T2. Keep time. The ECU 4 does not operate the pedestrian protection unit 3 even if the acceleration in the front-rear direction of the vehicle 6 exceeds the second threshold until the time measuring unit 5 measures the predetermined time T2.
When the longitudinal acceleration is equal to or greater than the third threshold, the pedestrian protection unit 3 can be operated to protect the pedestrian even before the predetermined time T2 has elapsed.

  In the modified example 3, since the pedestrian protection unit 3 is configured not to operate until the predetermined time T2 elapses after the vertical acceleration falls below the first threshold value, A malfunction of the pedestrian protection unit 3 can be reliably prevented.

(Modification 4)
FIG. 11 is a flowchart showing a processing procedure of the ECU 4 according to the fourth modification. The ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S91), and determines whether the vertical acceleration detected by the first detection unit 1 is equal to or greater than a first threshold value. Determination is made (step S92).

  When it is determined that the vertical acceleration is less than the first threshold (step S92: NO), the ECU 4 detects the longitudinal acceleration of the vehicle 6 using the second detection units 2a, 2b, and 2c (step S93). ), It is determined whether or not the longitudinal acceleration of the vehicle 6 detected by the second detectors 2a, 2b, and 2c is greater than or equal to a second threshold value (step S94). When the longitudinal acceleration is less than the second threshold (step S94: NO), the ECU 4 returns to step S91 and executes the loop again.

  When the longitudinal acceleration is equal to or greater than the second threshold value (step S94: YES), the ECU 4 outputs a control signal to the pedestrian protection unit 3 to operate the pedestrian protection unit 3 (step S95) and process Finish.

  When it is determined in step S92 that the vertical acceleration is greater than or equal to the first threshold (step S92: YES), the ECU 4 substitutes 1 for the variable N (step S96). The process after step S96 is a process for restricting the operation of the pedestrian protection unit 3 when traveling on a rough road. Further, the variable N is a variable for indicating the number of updates in a period in which the operation of the pedestrian protection unit 3 is restricted. Then, the ECU 4 resets the timer unit 5 and causes the timer unit 5 to start timing (step S97).

  Next, the ECU 4 determines whether or not the time measured by the time measuring unit 5 has passed the predetermined time T1 (step S98). When it is determined that the predetermined time T1 has elapsed (step S98: YES), the ECU 4 returns the process to step S91.

  When it is determined that the predetermined time T1 has not elapsed (step S98: NO), the ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S99), and the first detection unit 1 It is determined whether or not the vertical acceleration detected in step S <b> 1 is less than the first threshold value and has increased again to a value greater than or equal to the first threshold value from the low value side (step S100).

  When the vertical acceleration detected by the first detection unit 1 is less than the first threshold value and increases again from the low value side to the first threshold value (step S100 :: YES), the ECU 4 sets the variable N to 1. Is added (step S101), and it is determined whether or not the variable N after the addition is equal to or less than a predetermined number of times (step S102). As will be described later, in the modified example 4, the period for limiting the operation of the pedestrian protection unit 3 can be updated. However, the upper limit of the number of updates is the predetermined number, and the EEPROM of the ECU 4 sets the predetermined number of times. I remember it. When it is determined that the variable N is equal to or less than the predetermined number (step S102: YES), the ECU 4 returns the process to step S97.

  When it is determined that the variable N is larger than the predetermined number of times (step S102: NO), or when it is determined in step S100 that the vertical acceleration is continued below the first threshold or at the first threshold or higher. (Step S100: NO), ECU4 detects the acceleration of the vehicle 6 in the front-back direction in 2nd detection part 2a, 2b, 2c (step S103). Next, the ECU 4 determines whether or not the longitudinal acceleration detected by the second detectors 2a, 2b, and 2c is greater than or equal to a third threshold (step S104). When it is determined that the longitudinal acceleration is less than the third threshold (step S104: NO), the ECU 4 returns the process to step S98. If it is determined that the longitudinal acceleration is greater than or equal to the third threshold value (step S104: YES), the ECU 4 operates the pedestrian protection unit 3 (step S95) and ends the process. ECU4 is controlling the operation | movement of the pedestrian protection part 3 by performing the above process.

FIG. 12 is a graph for explaining the processing content of the ECU 4 according to the modification 4. FIG. 12A shows the acceleration change in the vertical direction of the vehicle 6, and FIG. 12B shows the timekeeping state of the timekeeping unit 5. In the modified example 4, the period indicated by hatching is configured such that pedestrian detection is not performed as a period during which an impact occurs when traveling on a rough road. In the modified example 4, when the vertical acceleration exceeds the first threshold value, the ECU 4 determines that the vehicle is traveling on a rough road until the predetermined time T1 elapses. The pedestrian protection unit 3 is not operated even if the acceleration of the vehicle exceeds the second threshold.
Further, in Modification 4, when the acceleration becomes less than the first threshold before the predetermined time T1 elapses after the vertical acceleration exceeds the first threshold, and again when the acceleration exceeds the first threshold, A process of measuring the predetermined time T1 again is performed. That is, the period during which the operation of the pedestrian protection unit 3 is restricted is updated every time the vertical acceleration exceeds the first threshold. However, the recounting of the predetermined time T1 is limited to a predetermined number of times or less.
In addition, when the acceleration in the front-rear direction is equal to or greater than the third threshold, when the acceleration in the vertical direction exceeds the first threshold, the pedestrian protection unit 3 is operated even before the predetermined time T1 has elapsed, Pedestrians can be protected.

  In the fourth modification, the longitudinal acceleration detection of the vehicle 6 and the collision determination process with the pedestrian are not executed for a predetermined time T1 after the vertical acceleration exceeds the first threshold. Since the predetermined time T1 is re-timed when the vertical acceleration exceeds the first threshold value, the pedestrian protection unit may be mistaken even when the rough road driving period continues. The operation can be prevented.

  In Modification 4, the number of updates is a predetermined number of times as a condition for releasing the state in which the operation of the pedestrian protection unit 3 is restricted in a state where the vertical acceleration continuously fluctuates. Although the method to restrict | limit below was demonstrated, it is an example to the last, and you may comprise so that the restriction | limiting of operation | movement of the pedestrian protection part 3 may be cancelled | released with another logic. Judgment may be made in consideration of the magnitude of acceleration in the vertical direction, fluctuation patterns, and other travel conditions.

(Modification 5)
FIGS. 13 and 14 are flowcharts illustrating the processing procedure of the ECU 4 according to the fifth modification. The ECU 4 detects the acceleration in the vertical direction of the vehicle 6 by the first detection unit 1 (step S111), and determines whether the vertical acceleration detected by the first detection unit 1 is equal to or greater than a first threshold value. Determination is made (step S112).

  When it is determined that the vertical acceleration is less than the first threshold (step S112: NO), the ECU 4 detects the longitudinal acceleration of the vehicle 6 using the second detection units 2a, 2b, and 2c (step S113). ), It is determined whether or not the acceleration in the front-rear direction of the vehicle 6 detected by the second detectors 2a, 2b, and 2c is greater than or equal to the second threshold (step S114). When the longitudinal acceleration is less than the second threshold (step S114: NO), the ECU 4 returns to step S111 and executes the loop again.

  When the longitudinal acceleration is equal to or greater than the second threshold (step S114: YES), the ECU 4 outputs a control signal to the pedestrian protection unit 3 to operate the pedestrian protection unit 3 (step S115), and processing Finish.

  When it is determined in step S112 that the vertical acceleration is greater than or equal to the first threshold (step S112: YES), the ECU 4 substitutes 1 for a variable N (step S116). The process after step S116 is a process for restricting the operation of the pedestrian protection unit 3 when traveling on a rough road. The ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S117), and determines whether the vertical acceleration detected by the first detection unit 1 is less than the first threshold value. Determination is made (step S118).

  When it is determined that the vertical acceleration detected by the first detection unit 1 is greater than or equal to the first threshold (step S118: NO), the ECU 4 uses the second detection units 2a, 2b, and 2c to move the vehicle 6 back and forth. Directional acceleration is detected (step S119). Next, the ECU 4 determines whether or not the longitudinal acceleration detected by the second detectors 2a, 2b, and 2c is equal to or greater than a third threshold value (step S120). The third threshold value is the same value as in the fifth modification example, and the EEPROM of the ECU 4 stores the third threshold value. When it determines with the acceleration of the front-back direction being less than a 3rd threshold value (step S120: NO), ECU4 returns a process to step S117. If it is determined that the longitudinal acceleration is greater than or equal to the third threshold (step S120: YES), the ECU 4 operates the pedestrian protection unit 3 (step S115) and ends the process.

  When it is determined that the vertical acceleration is less than the first threshold (step S118: YES), the ECU 4 resets the time measuring unit 5 and causes the time measuring unit 5 to start measuring time (step S121). Then, the ECU 4 determines whether or not the time measured by the time measuring unit 5 has passed the predetermined time T2 (step S122). When it is determined that the predetermined time T2 has elapsed (step S122: YES), the ECU 4 returns the process to step S111.

  When it is determined that the predetermined time T2 has not elapsed (step S122: NO), the ECU 4 detects the vertical acceleration of the vehicle 6 by the first detection unit 1 (step S123), and the first detection unit 1 It is determined whether or not the vertical acceleration detected in step 1 is equal to or greater than a first threshold (step S124). That is, it is determined whether or not the vertical acceleration has fallen below the first threshold value but again exceeds the first threshold value and the vehicle has entered a rough road running state.

  When it is determined in step S124 that the vertical acceleration is greater than or equal to the first threshold (step S124: YES), the ECU 4 adds 1 to the variable N (step S125), and the variable N after the addition is equal to or less than the predetermined number. It is determined whether or not there is (step S126). As will be described later, in the modified example 5, the period for limiting the operation of the pedestrian protection unit 3 can be updated, but the upper limit of the number of updates is the predetermined number, and the EEPROM of the ECU 4 sets the predetermined number of times. I remember it. When it is determined that the variable N is equal to or less than the predetermined number (step S126: YES), the ECU 4 returns the process to step S117.

  When it is determined that the variable N is greater than the predetermined number of times (step S126: NO), or when it is determined in step S124 that the vertical acceleration is less than the first threshold value (step S124: NO), the ECU 4 performs the second detection. The parts 2a, 2b and 2c detect the longitudinal acceleration of the vehicle 6 (step S127). Next, the ECU 4 determines whether or not the longitudinal acceleration detected by the second detectors 2a, 2b, and 2c is equal to or greater than a third threshold (step S128). If it is determined that the longitudinal acceleration is less than the third threshold (step S128: NO), the ECU 4 returns the process to step S122. If it is determined that the longitudinal acceleration is greater than or equal to the third threshold value (step S128: YES), the ECU 4 operates the pedestrian protection unit 3 (step S115) and ends the process. ECU4 is controlling the operation | movement of the pedestrian protection part 3 by performing the above process.

FIG. 15 is a graph for explaining the processing contents of the ECU 4 according to the fifth modification. FIG. 15A shows the acceleration change in the vertical direction of the vehicle 6, and FIG. 15B shows the timekeeping state of the timekeeping unit 5. In the modified example 5, as in the modified example 3, the period indicated by hatching is configured so as not to perform pedestrian detection as a period in which an impact occurs when traveling on a rough road. In the modified example 5, when the vertical acceleration exceeds the first threshold, the ECU 4 determines that the vehicle is traveling on a rough road, and even if the longitudinal acceleration exceeds the second threshold, the pedestrian The protection unit 3 is not operated. When the acceleration in the vertical direction exceeds the first threshold value, the timer unit 5 enters a timing start waiting state, starts timing when the acceleration falls below the first threshold value, and measures a predetermined time T2. The ECU 4 is configured not to determine that a collision with a pedestrian has occurred even if the longitudinal acceleration of the vehicle 6 exceeds the second threshold until the time measuring unit 5 measures the predetermined time T2. Yes.
Further, in Modification 5, when the vertical acceleration again exceeds the first threshold before the predetermined time T2 elapses, the state again enters a timing start waiting state, and the predetermined time T2 is measured in the same procedure. . That is, the process which updates the invalid period which does not operate the pedestrian protection part 3 at the time of rough road driving is performed each time. However, the number of times that the invalid period can be updated is up to the predetermined number.
In addition, when the acceleration in the front-rear direction is equal to or greater than the third threshold, when the acceleration in the vertical direction exceeds the first threshold, the pedestrian protection unit 3 is operated even before the predetermined time T2 has elapsed, Pedestrians can be protected.

  In the modified example 5, the pedestrian protection unit 3 is basically not operated until the predetermined time T2 elapses after the vertical acceleration falls below the first threshold. Therefore, malfunction of the pedestrian protection unit 3 can be prevented more reliably. Moreover, since it is comprised so that the period which restrict | limits operation | movement of the pedestrian protection part 3 may be updated whenever the state where the acceleration of an up-down direction exceeds a 1st threshold value continues, it is by continuing a rough road driving | running | working. A malfunction of the pedestrian protection unit 3 can also be prevented.

  In Modification 5, the number of updates is a predetermined number of times as a condition for canceling the state in which the operation of the pedestrian protection unit 3 is restricted while the vertical acceleration continuously fluctuates. Although the method to restrict | limit below was demonstrated, it is an example to the last like the modification 4.

  The embodiments disclosed herein are illustrative in all respects and should not be considered as restrictive. The scope of the present invention is defined not by the above-mentioned meaning but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

1 1st detection part 2a, 2b, 2c 2nd detection part 3 Pedestrian protection part (protection part)
4 ECU (means for judging)
5 Timekeeping section 6 Vehicle 6a Front bumper 6b Rear bumper A Rear part of axle of rear wheel

Claims (8)

A first detection unit that detects acceleration in the vertical direction of the vehicle; a second detection unit that detects acceleration in the front-rear direction or in the lateral direction of the vehicle; and a protection unit that protects the collision target. In the collision object protection apparatus configured to operate based on the detection results of the first detection unit and the second detection unit,
The first detection unit includes:
The collision object protection device according to claim 1, wherein the collision object protection device is arranged at a portion excluding a rear portion from an axle portion of a front bumper and a rear wheel of the vehicle. The first detection unit includes:
The collision object protection device according to claim 1, wherein the collision object protection device is disposed between a front bumper and an axle portion of a rear wheel in the front-rear direction of the vehicle. The second detector is
The collision object protection device according to claim 1, wherein the collision object protection device is disposed on a front bumper of the vehicle. Means for determining whether the acceleration detected by the first detection unit is equal to or greater than a first threshold;
Means for determining whether the acceleration detected by the second detection unit is equal to or greater than a second threshold;
The protective part is
The apparatus is configured to operate when the acceleration detected by the first detection unit is less than a first threshold value and the acceleration detected by the second detection unit is greater than or equal to a second threshold value. The collision object protection device according to any one of claims 1 to 3. When it is determined that the acceleration detected by the first detection unit is equal to or greater than a first threshold, the timer unit starts timing.
The protective part is
The collision target according to claim 4, wherein the acceleration detected by the second detection unit is greater than or equal to a second threshold value, and the operation is performed when the timing unit counts a predetermined time or more. Protective device. The timing unit is
Before measuring the predetermined time, when the acceleration detected by the first detection unit becomes less than the first threshold value and becomes equal to or more than the first threshold value again, the timing unit is reset to start timing. The collision object protection device according to claim 5, wherein the collision object protection device is provided. When the acceleration detected by the first detection unit changes from the first threshold value or more to less than the first threshold value, the timer unit starts time measurement,
The protective part is
The collision target according to claim 4, wherein the acceleration detected by the second detection unit is greater than or equal to a second threshold value, and the operation is performed when the timing unit counts a predetermined time or more. Protective device. Means for determining whether or not the acceleration detected by the second detector is greater than or equal to a third threshold greater than a second threshold;
The protective part is
The operation according to any one of claims 4 to 7, wherein when the acceleration detected by the second detection unit is equal to or greater than a third threshold value, the operation is performed regardless of a detection result of the first detection unit. The collision object protection device according to any one of the above.

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