WO2007076735A2

WO2007076735A2 - Method and device for determining a triggering decision for restraint means of a vehicle

Info

Publication number: WO2007076735A2
Application number: PCT/DE2006/001877
Authority: WO
Inventors: Günter Fendt
Original assignee: Conti Temic Microelectronic Gmbh
Priority date: 2006-01-04
Filing date: 2006-10-24
Publication date: 2007-07-12
Also published as: DE102006000733A1; DE112006000058A5; WO2007076735A9; WO2007076735A3

Abstract

The invention relates to a method and to an associated device for determining a triggering decision for restraint means of a vehicle in the event of frontal crashes and side crashes, in order to obtain/permit better adaptation of the triggering decision to the events involved in the accident, in particular in the event of crash scenarios with preceding skidding processes/turning of the vehicle. An essential idea of the invention is that the modified sensitivity characteristic (with respect to the direction of the crash effect/force effect) of the directional crash-sensing sensors are compensated/corrected as a result of the turning of the vehicle or the changes in parameter which result from the turning of the vehicle, by virtue of the fact that the turning of the vehicle is sensed by means of one or more yaw rate sensors and corresponding corrective measures/compensation measures are carried out in the processing unit by means of the yaw rate information.

Description

Method and device for determining a triggering decision for

Retention means of a vehicle

The invention relates to a method for determining a triggering decision for restraining means of a vehicle according to the. Generic term of the independent claims.

Such collision systems are intended to mitigate the consequences of accidents for motor vehicle users in the event of a collision of the motor vehicle with a collision object, in particular by means of restraint systems such as belt tensioners and airbags.

In order to improve the safety of road users in traffic, occupant protection systems are being increasingly installed in vehicles with ever higher performance in order to protect / support the occupants of a vehicle as optimally as possible in every imaginable accident situation / driving situation. These include, above all, accident situations that do not correspond to a simple frontal collision, but accident events that, for example as a result of the accident obstacle (pedestrian or tree = pole crash) or the impact angle (oblique or side crash), a clear crash detection often only difficult, since the crash acceleration signals generated by the crash, are often very low in amplitude or due to a soft vehicle body only slowly spread in the vehicle and thus relatively difficult to be detected by the central control unit, which is preferably located on the center tunnel.

Especially in these accidents or accident types in which the crumple zone is often very low (eg side crash) or the obstacle (eg pedestrian) has only a relatively small mass, however, is a fast and safe sensing and detection of the crash Signatures generated of utmost importance so that relatively quickly and safely a trigger signal for the protective devices can be generated. In order to achieve an improvement here, it has begun to create systems in which so-called assistance sensors (side sensors / up-front sensors) with a variety of active principles, such as pressure structure-borne sound and acceleration sensors, are placed as close to the spot, in order to be able to recognize an impact as quickly as possible and to be able to continue to report to the central device, which is preferably placed in the middle of the vehicle.

From the published patent application DE 44 25 846 Al, to cite only a example as a representative of the variety of writings on this subject, a method for triggering side airbags of a passive safety device for motor vehicles is known in this the activation of the side airbags according to the invention by the evaluation of from a centrally located in the motor vehicle arranged frontal and side collisions detecting collision sensor as well as from a left and right side collision detecting collision sensor generating sensor signals by the occurring in a crash signals of the individual sensors are evaluated in terms of amplitude.

Since sensors / acceleration sensors which are generally directed at these systems, both in the central unit and in the outsourced assistance sensors, are used, the decisive disadvantage in all these systems is that these systems can only guarantee the desired triggering safety when the vehicle is in service a usual crash scenario is involved. By contrast, it becomes more and more problematic whenever the vehicle hurls before the actual crash (collision with an obstacle) or is subject to a spinning process, since then the directional crash-detecting sensors, as a result of the preceding vehicle rotation, no longer act in the intended direction (the Crash action / force occurs as a result of the vehicle rotation quasi from another direction), and thus the crash event with an altered sensor sensitivity characteristic, or capture with it changed parameters / sensor amplitudes.

The object of the present invention is therefore to propose a method and a device for determining a triggering decision for restraining means of a vehicle in frontal and side crashes in order to better adapt the triggering decision to the vehicle Accident, especially ^" in crash scenarios with previous spin operations / vehicle turns, to obtain / enable.

This object is achieved by a method for determining a triggering decision for restraining means of a vehicle having the features of claim 1 and by a corresponding device having the features of claim 10. Preferred embodiments / advantageous developments of the invention will become apparent from the dependent claims.

An essential idea of the invention is that the changed sensitivity characteristic (related to the direction of the crash / force) of the directional crash detection sensors, due to the vehicle rotation, or the vehicle rotation resulting parameter changes, compensated / corrected by the vehicle rotation by means of a or more yaw rate sensor (s) is detected, and corrective actions / compensatory actions are performed by the yaw rate information in the processing unit.

The invention now relates to a method and an associated device for determining a triggering decision for restraining means of a vehicle in a side or frontal crash, in which a processing unit evaluates signal information from at least one directional acceleration sensor with a sensitivity characteristic following the alignment and at least one yaw rate sensor, wherein the processing unit in the trigger decision for the activation of the restraining means in a side or frontal crash, the angle of rotation (ωx, coy, ωz) of the vehicle is taken into account by taking into account the yaw rate information in the triggering decision.

For this purpose, according to the invention, by means of the yaw rate information which arises or is available by rotation of the vehicle from its nominal position, a compensation or a corrective measure is applied to at least one of the characteristic changes resulting from the vehicle rotation or to the associated variables or at least one of the vehicle-rotation-resultant parameter change or related quantity. In the simplest case, this compensation or Korrekturmaßnahαtne by means of a calculation rule, by means of this in the sensitivity, as a result of the vehicle rotation, modified directional acceleration signal of the acceleration sensor is corrected according to the vehicle rotation by the acceleration information of the vehicle in the desired position in accordance with Crash direction aligned acceleration sensor, are multiplied by the inverse of the cosine of the angle of vehicle rotation when the angle of the sensitivity direction of the acceleration sensor, due to the vehicle rotation of the crash direction has increased (the sense of direction of the directional sensor of the direction of Crasheinwirkung / force action turned away has been).

Similarly, the compensation or corrective action by means of a calculation rule, by means of which in the sensitivity, as a result of the vehicle rotation, modified directional acceleration signal of the acceleration sensor is corrected according to the vehicle rotation by the acceleration information, the aligned in the vehicle target position in Crashrichtung An acceleration sensor multiplied by the cosine of the angle of vehicle rotation when the angle of the sensitivity direction of the acceleration sensor due to the vehicle rotation has decreased from the crash direction (the sensitivity direction of the directional sensor has been rotated from the direction of the crash action / force action). The latter is the case, for example, when the directional sensors are in an inclined position or at a predetermined angle (not equal to 0 degrees / 90 degrees) to one of the vehicle main axes, or the crash to be detected is, for example, an oblique crash / oblique Crash, which is detected by sensors whose sensitivity axes parallel to the vehicle main axes extending.

As an alternative to the illustrated compensation by means of the above-described angle correction, the compensation or corrective action can be corrected by the acceleration information, in the sensitivity, as a result of the vehicle rotation, modified directional acceleration signal of the acceleration sensor corresponding to the vehicle rotation of the acceleration sensor aligned in the crash direction at the vehicle target position, according to the correction values of a stored table / matrix, or weighted.

As a further alternative thereto, it may be added that the calculation precursor can correct the acceleration sensor directional acceleration signal changed in sensitivity as a result of the vehicle rotation, according to the vehicle rotation, by calculating in the processing unit a correction of the integration time constant of the acceleration signals corresponding to vehicle rotation Corresponding correction of the tripping thresholds, caused.

It should be explained that the vehicle rotation can be a rotation about one of the vehicle's main axes (ωx, ωy, ωz), or a combination of a rotation about several of the vehicle's main axes (ωx, ωy, ωz).

For the sake of completeness, it should be mentioned that the term "directional sensors / directional acceleration sensors" is to be understood as meaning that the sensors / acceleration sensors have no uniform, all-round sensitivity characteristic independent of installation, but have a preferred sensitivity direction that depends on the installation direction. and the sensor sensitivity of the sensor describes a function, depending on the deviation of the sensitivity direction of the sensor for the action of force / acceleration, as described in more detail in FIG. 5, for example.

Further advantages or possible applications of the present invention will become apparent from the following description in conjunction with the embodiments illustrated in the drawings / Figures 1 to 5 and the associated method.

In the description, in the claims, in the abstract and in the appended drawings, the terms and associated reference numerals used in the list of reference numerals recited below are used. The drawings show in

Figure 1: A representation of a motor vehicle (1) in the longitudinal direction, in a normal position, and in a rotated about the vehicle longitudinal axis by the angle ωx position.

Figure 2: A principal possible sensor arrangement of an occupant protection system for a motor vehicle according to the prior art, partly with symbolically represented sensitivity characteristics (3.1.y, 3.2.x) of the side and vome directed sensors (3.1, 3.2).

Figure 3: analogous to Figure 2, with the difference that the vehicle is shown rotated by the rotation angle ωz.

Figure 4: The alternative possibility of the usual arrangements of the directions of action of the directional Accelerators in the central unit, according to the prior art.

5 shows a basic illustration of the sensitivity characteristic of a directional sensor, in which the sensing sensitivity (the sensor becomes correspondingly less sensitive when exposed from one direction to the angle) as a function of the cosine of the angle of rotation.

Because of the clarity, the actual restraining means of the vehicle are not shown here in detail in the following figures / drawings.

FIG. 1 shows a representation of a motor vehicle (1) in the longitudinal direction, in a normal position, as well as in a position rotated about the vehicle longitudinal axis by the angle ωx. As can be seen from the right drawing, by the angle ωx rotated vehicle representation, the symbolic sensitivity characteristic (3.1.y) of the tilted to the side sensor so that the sensor in a crash from the side, the acceleration signals / forces can no longer fully detect, but the acceleration signals / forces acting as a result of the vehicle rotation only attenuated with the cosine ωx detect or can forward.

In order for this signal, which is attenuated or transmitted with the cosine ωx, not to impair / detune the algorithm or the triggering decision for the restraining means of a vehicle (1) in the illustrated side crash scenario, the signal information of the directional acceleration sensor is generated in the downstream processing unit compensates with the rotational angle information of the yaw rate sensor (4) by multiplying the attenuated acquired signal information of the directional acceleration sensor by the inverse of the cosine ωx (or dividing by the cosine ωx).

As possible crash scenarios in the right-hand illustration, as shown in detail, it is conceivable that a side crash is caused by a vehicle coming from "right", or the vehicle (1) itself bounces against an obstacle, not shown in detail, both crashes Scenarios are, for example, possible if in advance of the actual crash, the driver of the vehicle shown (1) has tried an evasive maneuver in which the vehicle (1) has set up as shown.

FIG. 2 shows a principal possible sensor arrangement of an occupant protection system for a motor vehicle according to the prior art, in which the sensitivity characteristics (3.1.y, 3.2.x) of the side and forward sensors (3.1, 3.2) are partly determined. symbolically represented. As can be seen from the figure, the side sensors (3.1) can in this case contain a plurality of directional sensors.

The assistance sensors (3.1, 3.2, 3.3) arranged at the vicinity of the vehicle outer skin of the vehicle (1) are connected to the centrally arranged processing unit (2), so that the latter receives the signals detected by the assistance sensors for further utilization (FIG. Formation of a triggering decision) can. Furthermore (in addition to the SdT), information from a yaw rate sensor (4) acting in the vehicle vertical axis is fed to the centrally arranged processing unit (2) so that any centrifugal movements / vehicle rotational movements about the vehicle vertical axis can be detected in the processing unit (2) and processed accordingly ,

FIG. 3 shows by analogy with FIG. 2 the vehicle according to the prior art, with the difference that the vehicle (1) is shown rotated by the angle of rotation ωz. If, in this vehicle arrangement, a crash occurs from the direction of travel or the transverse direction, the directional sensors, as already discussed in FIG. 1, can reduce the acting forces / accelerations as a result of the vehicle rotation only with a reduced amplitude shape, or only with the cosine Detect or forward ωz, so that here again analogous to Figure 1, to ensure the desired functionality, a corresponding signal compensation is again make.

In order for this signal, which is detected by the cosine ωz to be attenuated or not transmitted, to impair / detune the algorithm or the triggering decision for the restraining means of a vehicle (1) in the illustrated frontal or side-crash scenario, the signal information in the downstream processing unit the directional acceleration sensor, with the rotational angle of the yaw angle sensor (4) compensated by the attenuated detected signal information of the directional acceleration sensors multiplied by the inverse of the cosine ωz (or divided by the cosine ωz).

As a possible crash scenarios in this representation, as not shown in more detail, it is conceivable that a side crash is caused by a vehicle coming from the transverse safety direction or from the direction of travel, or the vehicle (1) itself in this position against a (in the direction of travel or in the transverse direction). not shown obstacle bounces. Both crash scenarios are possible, for example, if in advance of the actual crash, the driver of the vehicle shown (1) has tried an evasive maneuver in which the vehicle (1) has rotated around the vehicle's vertical axis, as shown, or the vehicle during braking Smooth ice from the track device or begins to turn. FIG. 4 shows the alternative possibility of the common arrangements of the directions of action of the directional acceleration scavengers in the central device, according to the prior art.

In the arrangement of the directional acceleration sensors according to "A", with a sensitivity characteristic of the sensors parallel to the vehicle ^'s main axes (x, y), the sensor signals, in an unwanted vehicle rotation about the vehicle vertical axis, multiplied by the inverse of the cosine of the angle of vehicle rotation be so that a compensation according to the invention of the (due to the vehicle rotation about the vehicle vertical axis) attenuated sensor signals is carried out because the sensitivity direction of the directional sensors from the "crash direction" is turned off (the angle is increased).

In the arrangement of the directional acceleration sensors according to "B", with a sensitivity characteristic of the sensors different from the vehicle main axes (x, y), the sensor signals, in an unwanted vehicle rotation about the vehicle vertical axis, with the cosine of the angle of the vehicle rotation must be multiplied by a Compensation according to the invention (as a result of the vehicle rotation about the vehicle vertical axis) amplified sensor signals takes place, since the sensitivity of the directional sensors is turned to the "crash direction" (the angle is reduced). One of the arrangement "B" analog compensation is also carried out in the assistance sensors, if they have a significantly different from the main axes Embaurichtung.

Figure 5 shows a basic representation of the sensitivity characteristic of a directional sensor, in which the Sensier sensitivity (the sensor is correspondingly less sensitive when exposed from a direction with the angle) as a function of the cosine of the rotation angle decreases.

As can be seen from the illustration, the sensor has its greatest sensitivity at zero degrees (100%). If the force or acceleration action takes place in a direction deviating from zero degrees, the sensitivity of the sensor, or the ability to sense the force or acceleration action, decreases in percent according to the function shown (E = f (cos angle)) , LIST OF REFERENCE NUMBERS

1 vehicle

2 processing unit

3.1 Sensor / acceleration sensor in a side assistance sensor (y-direction)

3.1.y Sensitivity characteristics of the sensor / acceleration sensor 3.1

3.2 Sensor / acceleration sensor in a front-assistance sensor (x-direction) 3.2.x Sensitivity characteristics of the sensor / acceleration sensor 3.2

3.3 Sensor / acceleration sensor in a front-assistance sensor (x-direction) 4 yaw rate sensor ωx angle of the vehicle rotation about the vehicle longitudinal axis (x-axis) ωy angle of the vehicle rotation about the vehicle transverse axis (y-axis) ωz angle of the vehicle rotation about the vehicle's vertical axis (z- Axis)

Claims

claims

1. A method for determining a triggering decision for restraining means of a vehicle (1) in a side or frontal crash, in which a processing unit (2) signal information from at least one directional acceleration sensor (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.5) one of the alignment following sensitivity characteristic (3. Ly, 3.2.x) and at least one yaw rate sensor (4), wherein the yaw rate information in the triggering decision are taken into account, characterized in that the processing unit (2) in the triggering decision for the activation of the retaining means at a side or frontal crash the angle of rotation (ωx, ωy, ωz) of the vehicle (1) taken into account by means of the yaw rate information, resulting from rotation of the vehicle from its desired position, a corrective action on at least one of the vehicle rotation resulting change in the sensitivity characteristic or in co sizing of the size.

2. The method according to claim 1, characterized in that the corrective action of the resultant by the vehicle rotation characteristic change or related size by means of a calculation rule.

3. The method according to claim 2, characterized in that the calculation rule corrects the direction in the sensitivity due to the vehicle rotation directional acceleration signal of the acceleration sensor or related size corresponding to the vehicle rotation.

4. Method according to claim 3, characterized in that the acceleration information of the acceleration sensor aligned at the vehicle target position in the crash direction is multiplied by the inverse of the cosine of the angle of the vehicle rotation when the angle of the sensitivity direction of the acceleration sensor as a result of vehicle rotation, has increased from the Crashrichtung.

5. The method according to claim 3, characterized in that the acceleration information of the vehicle in the desired position aligned in the direction of crash acceleration sensor is multiplied by the cosine of the angle of the vehicle rotation, when the angle of Senshchkeitsrichtung the acceleration sensor as a result of vehicle rotation, from the Crash direction has decreased.

6. The method according to any one of claims 1 to 3, characterized in that the acceleration information of the vehicle in the desired position corresponding aligned in Crashrichtung acceleration sensor according to the correction values of a stored table or matrix are changed or weighted.

7. The method according to any one of claims 1 to 3, characterized in that a calculation rule in the processing unit causes a vehicle rotation corresponding correction of the integration time constant of the acceleration signals or a corresponding correction of the tripping thresholds.

8. The method according to any one of the preceding claims, characterized in that it is at the vehicle rotation to a rotation about one of the vehicle main axes (ωx, ωy, ωz), or a combination of rotation about several of the vehicle main axes (ωx, ωy, ωz) is.

9. A device for determining a triggering decision for restraining means of a vehicle (1) in a side or frontal crash, consisting of a processing unit (2), at least one directional acceleration sensor (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.5) with a the orientation following sensitivity characteristic (3.1.y, 3.2.x) for detecting a vehicle acceleration or vehicle acceleration change, and at least one yaw rate sensor (4) for detecting a vehicle rotation (ωx, ωy, ωz), wherein the yaw rate information is taken into account in the triggering decision thereby characterized in that the processing unit (2) is designed to take into account the rotation angle of the vehicle (ωx, ωy, ωz) in the triggering decision for the activation of the restraining means in a side or frontal crash by using the yaw rate information generated by rotation of the vehicle whose target position is generated, a correct urmaßnahme on at least one of the vehicle rotation resulting change in the sensitivity characteristic or related size perform.

10. The device according to claim 9, characterized in that the corrective action of the resulting by the vehicle rotation change of the sensitivity characteristic or related size by means of a calculation rule.

11. The device according to claim 10, characterized in that the calculation instruction corrects the directional acceleration signal of the acceleration sensor changed in the sensitivity as a result of the vehicle rotation according to the vehicle rotation or changes or weights according to correction values of a stored table / matrix or corrects according to the vehicle rotation by a calculation rule in the processing unit causes a correction corresponding to the vehicle rotation of the integration time constant of the acceleration signals, or a corresponding correction of the triggering thresholds.

12. Device according to one of the preceding claims, characterized in that the correction by means of multiplying or dividing the cosine value of the angle takes place, with this the sensitivity axis of the accelerometer for the intended target crash detection direction, as a result of vehicle rotation, has been changed.

13. Device according to one of the preceding claims, characterized in that it detects a vehicle rotation about a rotation about at least one of the vehicle main axes (ωx, ωy, ωz), or a combination of rotation about a plurality of the vehicle main axes (ωx, ωy, ωz) ,