JP2007008226A - Collision object determining device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out collision determination with high accuracy by exactly estimating physical quantity due to actual collision from physical quantity detected in collision and a collision angle of an own vehicle of a collision object against the own vehicle. <P>SOLUTION: A car body slipping angle made by turning motion of the vehicle is computed in accordance with a steering wheel angle and a car velocity by a car body slipping angle computing part 10a on a collision object determining part 10. An actual collision load is computed by correcting a load in the longitudinal direction working on a front bumper 3 from a load quantity detection sensor 6 from a geometrical relation in accordance with the car body slipping angle on an actual collision load computing part 10b. Thereafter, determination of the collision object is carried out in accordance with the actual collision load on a collision object determining part 10c. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a collision object determination device for a vehicle that determines a collision of an obstacle such as a pedestrian.

  In recent years, various safety measures have been taken for vehicles, including the interior space, and recently, when there is a collision with a pedestrian, this pedestrian is effectively protected. Equipment to do is beginning to be proposed. In such pedestrian safety equipment, it is first required to accurately determine that the collided object is a pedestrian.

For example, in Japanese Patent Application Laid-Open No. 2002-127867, a plurality of acceleration sensors are provided in the vehicle width direction on the inner surface of a bumper face of a front bumper, and an obstacle is determined by processing signals from these acceleration sensors by a control unit. Technology is disclosed. Specifically, the ratio of the maximum deformation amount to the maximum deformation speed is smaller for lighter obstacles than for specific obstacles such as pedestrians. The control process is performed by the control unit. In other words, when the acceleration exceeds a certain threshold value, a timed timer is generated, and further, after the deformation speed exceeds the certain threshold value and exceeds the maximum value, a gate is generated from the time when the speed falls below the threshold value until the above timer time is reached. . During this time, a signal in a state where the displacement is within a certain width is generated, a signal is generated from an AND condition of this signal and the above-described gate, and a pedestrian collision is determined based on this signal. It has become.
JP 2002-127867 A

  However, in the technology disclosed in Patent Document 1 described above, since the collision angle of the collision object with respect to the own vehicle is not taken into consideration, the forward subduction of the nose dive generated when the own vehicle is turning or due to braking is not considered. Depending on the state, the physical quantity at the time of collision cannot be accurately detected by the sensor, and there is a possibility that accurate collision determination cannot be performed.

  The present invention has been made in view of the above circumstances, and is a vehicle collision object capable of accurately estimating a physical quantity due to an actual collision from a physical quantity detected at the time of a collision and a traveling posture of the host vehicle and performing a collision determination with high accuracy. An object of the present invention is to provide a determination device.

  The present invention provides a physical quantity detection means for detecting a physical quantity acting on the detection direction by attaching the vehicle in a predetermined direction as a detection direction, and the detection based on a difference in angle between the detection direction and the vehicle traveling direction. A physical quantity correction unit that corrects the physical quantity to be corrected, and a collision object determination unit that determines a collision object based on the physical quantity corrected by the physical quantity correction unit.

  The vehicle collision object determination device according to the present invention can accurately estimate a physical quantity due to an actual collision from the physical quantity detected at the time of the collision and the collision angle of the collision object with respect to the host vehicle, thereby enabling accurate collision determination.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 7 show a first embodiment of the present invention, FIG. 1 is an explanatory view of mounting a load amount detection sensor inside a front bumper portion of a vehicle, FIG. 2 is a cross-sectional view of a bumper beam, and FIG. FIG. 4 is a flowchart of the collision object determination program, FIG. 5 is a flowchart of the actual collision load F estimation routine, and FIG. 6 is an explanatory diagram of the relationship between the longitudinal load, the actual collision load, and the vehicle slip angle. FIG. 7 is an explanatory diagram showing examples of collision loads of various collision objects.

  In FIG. 1, reference numeral 1 denotes a vehicle, and a front bumper 3 is provided below the front hood 2 of the vehicle 1. The front bumper 3 includes a resin bumper face 4 that forms an exterior, and an aluminum alloy bumper beam 5 that is hollow inside and extends in the vehicle width direction. The bumper beam 5 is fixedly attached to a vehicle body frame (not shown), and is designed in shape and strength so that it rebounds in the direction in which the shape returns due to elasticity when it collides with a pedestrian.

  Inside the front bumper 3, one load amount detection sensor 6 as a physical amount detection means having a shape extending along the vehicle width direction is attached. The load amount detection sensor 6 detects a load amount Fy in the vehicle front-rear direction acting on the front bumper 3 as a physical amount, and outputs an output proportional to the load amount Fy. That is, the load amount detection sensor 6 is attached so that the load amount detection direction is directed in the front-rear direction of the vehicle. The load amount detection sensor 6 is provided on the front surface of the bumper beam 5 inside the front bumper 3 as shown in FIG.

  As shown in FIG. 3, the load amount detection sensor 6 is connected to the collision object determination unit 10, and inputs a front-rear direction load Fy signal acting on the front bumper 3 to the collision object determination unit 10. Further, the vehicle is provided with a handle angle sensor 7 that detects the handle angle θH and a vehicle speed sensor 8 that detects the vehicle speed V, and signals of the handle angle θH and the vehicle speed V are input to the collision object determination unit 10. .

  The collision object determination unit 10 determines a collision object based on each of the input signals described above, and outputs “ON determination” when the collision object can be determined as a pedestrian or the like. Therefore, the collision object determination unit 10 mainly includes a vehicle slip angle calculation unit 10a, an actual collision load calculation unit 10b, and a collision object determination unit 10c.

The vehicle body slip angle calculation unit 10 a receives the handle angle θH from the handle angle sensor 7 and the vehicle speed V from the vehicle speed sensor 8. Based on the equation of motion of the vehicle, in the relationship shown in FIG. 6A, the vehicle body slip angle β is calculated as the vehicle traveling direction by the following equation (1), and is output to the actual collision load calculating unit 10b.
β = ((1- (m / (2 · L)) · (Lf / (Lr · Kr)) · V ² )
/ (1+ (A · V ² ))) · (Lr / L) · (θH / n) (1)
Here, m is the vehicle mass, L is the wheel base, Lf is the distance between the front axle and the center of gravity, Lr is the distance between the rear axle and the center of gravity, Kr is the cornering power of the rear wheel, A is the stability factor of the vehicle, and n is the steering. Gear ratio.

Instead of using the steering wheel angle θH from the steering wheel angle sensor 7, the vehicle body slip angle β may be derived from the following equation (2) using the yaw rate γ from the yaw rate sensor (not shown).
β = (1- (m / (2 · L)) · (Lf / (Lr · Kr)) · V ² )
・ Lr ・ γ / V (2)

In the actual collision load calculation unit 10b, the load Fy in the front-rear direction acting on the front bumper 3 is input from the load amount detection sensor 6, and the vehicle slip angle β is input from the vehicle slip angle calculation unit 10a. Then, in the relationship shown in FIG. 6B, the actual collision load F is calculated by the following equation (3) and output to the collision object determination unit 10c.
F = Fy / cosβ (3)

  That is, the equation (3) is an equation for correcting the longitudinal load Fy acting on the front bumper 3 by the vehicle slip angle β generated by the turning motion of the vehicle. A physical quantity correction unit is configured by the collision load calculation unit 10b.

  The collision object determination unit 10c receives the vehicle speed V from the vehicle speed sensor 8 and the actual collision load F from the actual collision load calculation unit 10b. The vehicle speed V is equal to or higher than a preset threshold value Vc1 (for example, 15 to 20 km / h), and the actual collision load F is within the set range (the range of f1 to f2 in FIG. 7). Is within a certain time (range from t1 to t2 in FIG. 7), the collision object is determined to be a pedestrian and an ON determination signal is output.

  That is, the case where such an ON determination signal is output is a case like A0 in FIG. In the collision object determination unit 10c in the present embodiment, the ON determination is not performed when the vehicle speed V is less than the preset threshold value Vc1 and the vehicle can be regarded as traveling at a low speed. Further, as shown by A1 in FIG. 7, when the actual collision load F does not reach f1, it is obviously a lightweight collision object, so the ON determination is not performed. Furthermore, when it exceeds the load of f2 as shown by A2 of FIG. 7, since it seems that it is heavy articles, such as a side wall and a utility pole, ON determination is not performed. Further, as shown in A3 of FIG. 7, even if the actual collision load F falls within the range of f1 to f2, it may be a fixed object if the time does not fall within the range of t1 to t2. Because of the high nature, ON determination is not performed. Thus, the collision object determination unit 10c is provided as a collision object determination unit.

  Next, a collision object determination program executed by the collision object determination unit 10 will be described with reference to the flowchart of FIG. First, in step (hereinafter abbreviated as “S”) 101, the vehicle speed V is read, and the process proceeds to S102 to determine whether the vehicle speed V is equal to or higher than a preset threshold value Vc1 (for example, 15 to 20 km / h).

  As a result of the determination in S102, if it is determined that the vehicle speed V is less than the preset threshold value Vc1 and the vehicle is at a low speed, the process proceeds to S108, an initialization process is performed, and the processes from S101 are repeated again.

  As a result of the determination in S102, if it is determined that the vehicle speed V is equal to or higher than the preset threshold value Vc1, the process proceeds to S103, and the load Fy in the front-rear direction acting on the front bumper 3 is read from the load amount detection sensor 6.

  Thereafter, the process proceeds to S104, where an actual collision load F is estimated by an actual collision load F estimation routine of FIG. 5 described later, and the process proceeds to S105.

  In S105, it is determined whether or not the actual collision load F is within the set range (the range of f1 to f2 in FIG. 7). If the set load range is not reached or exceeds the set range, S108 is determined. Then, the initialization processing is performed, and the processing from S101 is repeated again.

  Further, when continuing within the set range, the process proceeds to S106, and it is determined whether or not the duration within the set range of the actual collision load F is within a certain time (range from t1 to t2 in FIG. 7).

  As a result of the determination in S106, if the duration within the set range of the actual collision load F is within a certain time, it is determined that the collision object is a pedestrian, the process proceeds to S107, an ON determination is output, and the program is executed. Exit. On the other hand, if the duration within the set range of the actual collision load F exceeds a certain time, the process proceeds to S108, initialization processing is performed, and the processing from S101 is repeated again.

  Next, FIG. 5 shows an actual collision load F estimation routine executed in S104 described above. First, in S201, the steering wheel angle θH and the vehicle speed V are read.

  Next, the process proceeds to S202, where the vehicle slip angle β is calculated by the above-described equation (1).

  Then, the process proceeds to S203, where the actual collision load F is calculated by the above-described equation (3) and the routine is exited.

  Thus, according to the first embodiment of the present invention, the actual collision load Fy is corrected by correcting the longitudinal load Fy acting on the front bumper 3 at the vehicle body slip angle β generated by the turning motion of the vehicle. And the collision determination is performed with the estimated actual collision load F, so that the collision determination with high accuracy can be performed.

  Next, FIGS. 8 to 10 show a second embodiment of the present invention, FIG. 8 is a functional block diagram of the collision object determination device, FIG. 9 is a flowchart of an actual collision load F estimation routine, and FIG. It is explanatory drawing of the relationship between a load, an actual collision load, and a pitching angle. The second embodiment is different from the first embodiment in that the actual collision load F is estimated by correcting the longitudinal load Fy by the angle generated by the pitching motion of the vehicle. Since this is the same as the first embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.

  That is, as shown in FIG. 8, in addition to the load amount detection sensor 6 and the vehicle speed sensor 8 described above, the vehicle has a ground height at the front and rear (vehicle front ground height hf, vehicle rear ground height hr). The ground height sensors 21f and 21r configured by a known laser distance sensor or the like are provided.

  The signals of the front-rear direction load Fy, the vehicle speed V, the vehicle front ground clearance hf, and the vehicle rear ground clearance hr applied to the front bumper 3 by the sensors 6, 8, 21f, and 21r are the collision object determination unit 20. Is input.

  The collision object determination unit 20 determines a collision object based on each of the input signals described above, and outputs “ON determination” when the collision object can be determined as a pedestrian or the like. Therefore, the collision object determination unit 20 mainly includes a pitching angle calculation unit 20a, an actual collision load calculation unit 20b, and a collision object determination unit 10c.

The pitching angle calculation unit 20a receives the vehicle front ground clearance hf from the vehicle front ground clearance sensor 21f and the vehicle rear ground clearance hr from the vehicle rear ground clearance sensor 21r. In the relationship of FIG. 10B, the vehicle pitching angle θp is calculated as the vehicle traveling direction by the following equation (4), and is output to the actual collision load calculation unit 20b.
θp = arctan (((hf−hf0) − (hr−hr0)) / Ls)
... (4)
Here, Ls is the distance between the vehicle front ground clearance sensor 21f and the vehicle rear ground clearance sensor 21r, hf0 is the vehicle front ground clearance during normal travel, and hr0 is the vehicle rear ground clearance during normal travel (both in FIG. 10). (See (a)).

In the actual collision load calculation unit 20b, the load Fy in the front-rear direction acting on the front bumper 3 is input from the load amount detection sensor 6, and the pitching angle θp of the vehicle is input from the pitching angle calculation unit 20a. Then, in the relationship shown in FIG. 10B, the actual collision load F is calculated by the following equation (5), and is output to the collision object determination unit 10c.
F = Fy / cos θp (5)

  That is, the equation (5) is an equation for correcting the longitudinal load Fy acting on the front bumper 3 with the pitching angle θp generated by the pitching motion of the vehicle, and the pitching angle calculation unit 20a and the actual collision load are corrected. The arithmetic unit 20b constitutes a physical quantity correction unit.

  Next, FIG. 9 shows an actual collision load F estimation routine that is specific to the second embodiment of the present invention and that is executed in S104 of FIG. 4 in the first embodiment.

  First, in S301, the vehicle front ground clearance hf and the vehicle rear ground clearance hr are read.

  Next, the process proceeds to S302, where the pitching angle θp of the vehicle is calculated by the above-described equation (4).

  Then, the process proceeds to S303, where the actual collision load F is calculated by the above-described equation (5) and the routine is exited.

  As described above, according to the second embodiment of the present invention, the actual collision load F is obtained by correcting the longitudinal load Fy acting on the front bumper 3 with the pitching angle θp generated by the pitching motion of the vehicle. Since the collision is determined using the estimated actual collision load F, the collision can be determined with high accuracy.

  In the second embodiment of the present invention, the ground height sensors 21f and 21r are described as examples of laser distance sensors, but the present invention is not limited to this. For example, the vehicle front end and the vehicle rear end are described. A GPS (Global Positioning System) may be mounted on the part, and the ground height from the GPS may be used.

  In addition, the value from the load amount detection sensor 6 may be corrected based on data in which the relationship between the acceleration applied to the vehicle when the brake is depressed and the pitching angle are mapped in advance (in this case, the value varies depending on the time of boarding and loading). For the ground clearance, the distance is measured and corrected in advance with a laser distance sensor, GPS, or the like).

  Further, the value from the load amount detection sensor 6 may be corrected based on data obtained by mapping the vehicle inclination angle (pitching angle) from the relationship of the brake pressure to the vehicle speed.

  Further, a displacement meter may be added to the suspension, and the value from the load amount detection sensor 6 may be corrected by obtaining the degree of vehicle depression.

  Furthermore, a known pitching sensor capable of directly measuring the tilt angle may be added to the vehicle to directly obtain the vehicle pitching angle and correct the value from the load amount detection sensor 6.

  Next, FIGS. 11 and 12 show a third embodiment of the present invention, FIG. 11 is a functional block diagram of the collision object determination device, and FIG. 12 is a flowchart of an actual collision load F estimation routine. In the third embodiment, the actual collision load F is estimated by correcting the longitudinal load Fy based on the vehicle slip angle generated by the turning motion of the vehicle and the angle generated by the pitching motion of the vehicle. Unlike the first and second embodiments, the other configurations and operations are the same as those of the first and second embodiments, so the same components are denoted by the same reference numerals and description thereof is omitted.

  That is, as shown in FIG. 11, the vehicle is provided with a load amount detection sensor 6, a handle angle sensor 7, a vehicle speed sensor 8, a vehicle front ground height sensor 21f, and a vehicle rear ground height sensor 21r. 6, 7, 8, 21F, and 21R output from the front bumper 3 acting on the front bumper 3, the signals Fy, the steering wheel angle θH, the vehicle speed V, the vehicle front ground height hf, and the vehicle rear ground height hr Input to the object determination unit 30.

  The collision object determination unit 30 determines a collision object based on each of the input signals described above, and outputs “ON determination” when the collision object can be determined as a pedestrian or the like. Therefore, the collision object determination unit 30 mainly includes a vehicle body slip angle calculation unit 10a, a pitching angle calculation unit 20a, an actual collision load calculation unit 30a, and a collision object determination unit 10c.

  In the actual collision load calculation unit 30a, the longitudinal load Fy acting on the front bumper 3 is input from the load amount detection sensor 6, the vehicle slip angle β is input from the vehicle slip angle calculation unit 10a, and the pitching angle calculation unit 20a. To the vehicle pitching angle θp.

And the actual collision load F is calculated by the following (6) Formula, and it outputs to the collision object determination part 10c.
F = ((Fy / cos β) ² + (Fy · tan θp) ² ) ^1/2 (6)

  That is, this equation (6) is a vehicle travel direction and load amount detection considering the left and right and up and down directions of the vehicle with the body slip angle β generated by the turning motion of the vehicle and the pitching angle θp generated by the pitching motion of the vehicle. It is an equation for correcting the longitudinal load Fy acting on the front bumper 3 based on the difference in angle with the detection direction of the sensor 6, and the vehicle slip angle calculating unit 10a, the pitching angle calculating unit 20a, and the actual collision load calculating unit. 30a constitutes a physical quantity correction means.

  Next, FIG. 12 shows an actual collision load F estimation routine that is specific to the third embodiment of the present invention and that is executed in S104 of FIG. 4 in the first embodiment.

  First, in S401, the steering wheel angle θH and the vehicle speed V are read.

  Next, it progresses to S402 and reads the vehicle front part ground clearance hf and the vehicle rear part ground clearance hr.

  Next, the process proceeds to S403, and the vehicle slip angle β is calculated by the above-described equation (1).

  Next, the process proceeds to S404, where the pitching angle θp of the vehicle is calculated according to the above equation (4).

  Then, the process proceeds to S405, where the actual collision load F is calculated by the above-described equation (6) and the routine is exited.

  Thus, according to the third embodiment of the present invention, the longitudinal load Fy acting on the front bumper 3 at the vehicle body slip angle β generated by the turning motion of the vehicle and the pitching angle θp generated by the pitching motion of the vehicle. Is corrected, the actual collision load F is estimated, and the collision determination is performed based on the estimated actual collision load F. Therefore, even if the vehicle is turning while accelerating or decelerating, the accuracy is improved. A good collision determination is possible.

  In each of the embodiments, the physical quantity is detected by the load quantity detection sensor 6 as the load Fy in the front-rear direction acting on the front bumper 3. However, the physical quantity is actuated on the front bumper 3 in the front-rear direction. The displacement may be detected by a displacement amount detection sensor, or the physical amount may be detected by an acceleration sensor as a longitudinal acceleration acting on the front bumper 3.

  Further, in each of the present embodiments, when the vehicle speed V is equal to or higher than the preset threshold value Vc1, the actual collision load F is within the set range, and the duration within the range is within a certain time, the collision object Is determined to be a pedestrian and outputs an ON determination signal, but the method of determination is not limited to this.

Installation explanatory drawing of the load amount detection sensor inside the front bumper part of the vehicle according to the first embodiment of the present invention Same as above, cross-sectional view of bumper beam Same as above, functional block diagram of collision object judgment device Same as above, flowchart of collision object determination program Same as above, flowchart of actual collision load F estimation routine Same as above, explanatory diagram of relationship between longitudinal load, actual collision load, and vehicle slip angle As above, explanatory diagrams showing examples of collision loads of various colliding objects Functional block diagram of a collision object determination device according to a second embodiment of the present invention Same as above, flowchart of actual collision load F estimation routine Same as above, explanatory diagram of relationship between longitudinal load, actual collision load and pitching angle Functional block diagram of the collision object determination device according to the third embodiment of the present invention Same as above, flowchart of actual collision load F estimation routine

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 3 Front bumper 4 Bumper face 5 Bumper beam 6 Load amount detection sensor (physical amount detection means)
7 Handle angle sensor 8 Vehicle speed sensor 10 Collision determination unit 10a Vehicle slip angle calculation unit (physical quantity correction means)
10b Actual collision load calculation unit (physical quantity correction means)
10c Collision determination unit (impact determination unit)

Claims (4)

A physical quantity detection means for detecting a physical quantity acting on the detection direction by attaching to the vehicle with a preset direction of the vehicle as a detection direction;
Physical quantity correction means for correcting the detected physical quantity based on the difference in angle between the detection direction and the vehicle traveling direction;
A collision object determination means for determining a collision object based on the physical quantity corrected by the physical quantity correction means;
A vehicle collision object determination device comprising:   The vehicle collision object determination device according to claim 1, wherein the difference in angle between the detection direction and the vehicle traveling direction is an angle difference generated by a turning motion of the vehicle.   The vehicle collision object determination device according to claim 1, wherein the difference in angle between the detection direction and the vehicle traveling direction is a difference in angle generated by a pitching motion of the vehicle.   2. The vehicle according to claim 1, wherein the difference in angle between the detection direction and the vehicle traveling direction is a difference in angle generated by a turning motion of the vehicle and a difference in angle generated by a pitching motion of the vehicle. Collision determination device.

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