DE102006000733A1 - Method and device for determining a triggering decision for restraining means of a vehicle - Google Patents

Abstract

The invention relates to a method and an associated device for determining a deployment decision for restraint means of a vehicle in frontal and side crashes in order to achieve / enable a better adaptation of the deployment decision to the accident, in particular in crash scenarios with previous skidding processes / vehicle turns. DOLLAR A An essential idea of the invention is that the changed sensitivity characteristics (related to the direction of the crash / force action) of the directional crash-sensing sensors as a result of the vehicle rotation or the parameter changes resulting from the vehicle rotation are compensated / corrected by the vehicle rotation by means of an or a plurality of yaw rate sensor / s is detected and corresponding corrective measures / compensation measures are carried out by means of the yaw rate information in the processing unit.

Description

The The invention relates to a method for determining a triggering decision for retention means of a vehicle according to the preamble of claim 1 and a corresponding device according to the preamble of claim 10.

such Impact systems to the consequences of accidents for motor vehicle users a collision of the motor vehicle with a collision object, in particular by means of Restraint systems such as belt tensioners and airbags, mitigate.

Around the security for Road users in traffic to improve are reinforced Occupant protection systems with ever higher performance in vehicles built to the occupants of a vehicle as optimally as possible in every conceivable Accident situation / driving situation protect / support too can. These include especially accident situations that do not correspond to a simple frontal impact, but accident events that, for example, as a result of the accident (Pedestrian or Tree = pole crash) or the impact angle (oblique or Side crash), a unique crash detection often difficult allow, there the crash acceleration signals generated by the crash, often are very low in amplitude or due to a soft vehicle body itself only slowly propagate in the vehicle and thus from the central control unit, which preferably located on the center tunnel, relatively difficult detected can be.

Just in these accidents or accident types in which the crumple zone is often very low is (e.g., page crash) or the obstacle (e.g., pedestrian) only one relatively low Mass possesses, however, is a quick and safe sensing and detection of crash-generated signatures of the utmost importance, hence relative fast and safe a trigger signal for the Protective devices can be generated.

Around To achieve an improvement here, one has gone to To create systems in which so-called assistance sensors (side sensors / up-front sensors) with the most varied principles of action, such as pressure-borne sound and acceleration sensors, as close as possible placed on the spot to be as possible to be able to quickly detect an impact and the central unit, which preferably placed in the middle of the vehicle, continue reporting to be able to.

From the publication DE 44 25 846 A1 For example, to cite just one example of a typeface representative of the multitude of documents on this subject, a method for triggering side airbags of a passive safety device for motor vehicles is known, in which the activation of the side airbags according to the invention by the evaluation of a centrally located in the motor vehicle frontal and side collision 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.

There in these systems, both in the central unit and in the outsourced ones Assistance sensors as a rule directed sensors / acceleration sensors to use is as a major disadvantage in all these Systems evaluate that these systems only then the desired trip security can guarantee if the vehicle is in a usual ongoing crash scenario is involved. Problematic, however It is always when the vehicle before the actual crash (Collision with an obstacle) hurls, or a spin is subject, since then the directional crash detection sensors, due the previous vehicle rotation, not in the designated Direction (the Crasheinwirkung / force effect occurs due the vehicle rotation quasi from another direction), and thus the crash event with an altered one Sensor sensitivity characteristic, or with it changed Capture parameters / sensor amplitudes.

task The present invention is therefore a method and a Device for determining a triggering decision for retaining means propose a vehicle in frontal and side crashes a better adaptation of the triggering decision looking at the accident, especially in crash scenarios with previous skidding / vehicle turns, to gain / enable.

These Task is by a method for determining a triggering decision for retention means a vehicle having the features of claim 1 and by a corresponding device with the features of claim 10 solved. preferred Embodiments / advantageous developments of the invention result 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 greed ratensensor / s is detected, and by means of the yaw rate information in the processing unit corresponding correction measures / compensation measures are performed.

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

According to the invention for this purpose by means of the yaw rate information obtained by turning the vehicle arising from its nominal position or are available, a compensation or a corrective action, at least one of the vehicle rotation resulting from the vehicle characteristic change or related quantity, or at least one the parameter change resulting from vehicle rotation or associated size.

in the The simplest case is the compensation or corrective action by means of a calculation rule, by means of which this in the sensitivity, as a result of vehicle rotation, changed directed acceleration signal of the acceleration sensor, accordingly the vehicle rotation is corrected by the acceleration information, in accordance with the vehicle target position in Crashrichtung aligned acceleration sensor, with the reciprocal of the cosine be multiplied by the angle of vehicle rotation when the Angle of the sensitivity direction of the acceleration sensor, as a result of vehicle rotation, has increased from the crash direction (The sensitivity direction of the directional sensor from the direction the Crasheinwirkung / force was turned away).

Analogous For this purpose, the compensation or corrective action by means of a calculation rule, by means of this in sensitivity, as a result of vehicle rotation, changed directed acceleration signal of the acceleration sensor, accordingly the vehicle rotation is corrected by the acceleration information, the aligned at the vehicle target position accordingly in crash direction Acceleration sensor, with the cosine of the angle of vehicle rotation multiplied when the angle of the sensitivity direction of the acceleration sensor, due to the vehicle rotation, of the Crash direction has decreased (the sensitivity direction of the directional sensor rotated by the direction of Crasheinwirkung / force has been). The latter is the case, for example, when the directed sensors in an inclined position or in a predetermined Angle (not equal to 0 degrees / 90 degrees) to one of the vehicle's main axes or, for example, the crash to be detected a slant / oblique Crash, which is detected by sensors whose sensitivity axes running parallel to the main vehicle axles.

alternative to the illustrated compensation by means of the above-described angle correction, the compensation or corrective action may result in the sensitivity, as a result of vehicle rotation, changed directed acceleration signal of the acceleration sensor, accordingly the vehicle rotation are corrected by the acceleration information, the at the vehicle target position corresponding in Crashrichtung aligned acceleration sensor, according to the correction values a stored table / matrix can be changed or weighted.

When Another alternative to this is added that the calculation rule the directional acceleration signal changed in sensitivity due to vehicle rotation of the acceleration sensor to be corrected according to the vehicle rotation can by adding a calculation rule in the processing unit a the vehicle rotation corresponding correction of the integration time constant of Acceleration signals, or a corresponding correction of the triggering thresholds, causes.

Be explanatory added, that the vehicle rotation is a rotation about one of the vehicle main axes (ωx, ωy, ωz), or a combination of a turn around several of the vehicle's main axes (ωx, ωy, ωz) act can.

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 Sensier sensitivity of the sensor a function, depending on the deviation of the sensitivity direction of the sensor to the force / acceleration, describes how this example in 5 closer represents / is explained.

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

In the description, in the claims, in the abstract and in the accompanying drawings the in the list below the reference numbers used terms and associated reference numerals used.

The Drawings show in

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

2 A principle 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 forward sensors ( 3.1 . 3.2 ).

3 : Analog of 2 , with the difference that the vehicle is shown rotated by the rotation angle ωz.

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

5 : A basic representation of the sensitivity characteristic of a directional sensor, in which the Sensier sensitivity (the sensor becomes less sensitive when acted upon by a direction with the / an angle) as a function of the cosine of the angle of rotation decreases.

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

1 shows a representation of a motor vehicle ( 1 ) in the longitudinal direction, in a normal position, as well as in a rotated about the vehicle longitudinal axis by the angle ωx position. As can be seen from the right-hand drawing, the vehicle representation rotated by the angle ωx, the symbolic sensitivity characteristic (FIG. 3.1.y ) of the side-facing sensor tilted down 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 vehicle rotation only attenuated with the cosine ωx detect or forward.

In order that this signal, which is attenuated with the cosine ωx, does not impair / detune the algorithm or the triggering decision for the restraining means of a vehicle ( 1 ) comes in the illustrated side crash scenario, in the downstream processing unit, the signal information of the directed acceleration sensor, with the rotation angle information of the yaw angle sensor ( 4 ) is compensated by multiplying the attenuated detected 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 representation, as is not shown in more detail, it is conceivable that a side crash is caused by a vehicle coming from "right" or the vehicle ( 1 ) bounces even in this position against an unspecified obstacle. Both crash scenarios are possible, for example, if, in the run-up to the actual crash, the driver of the vehicle shown ( 1 ) has tried an evasive maneuver in which the vehicle ( 1 ) as shown.

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

The near the vehicle outer skin of the vehicle ( 1 arranged to the front and to the side assistance sensors ( 3.1 . 3.2 . 3.3 ) are connected to the centrally arranged processing unit ( 2 ), so that the signals detected by the assistance sensors can be forwarded for further utilization (formation of a triggering decision). Furthermore (in addition to the SdT), the centrally arranged processing unit ( 2 ) Information from a yaw rate sensor acting in the vehicle's vertical axis ( 4 ), so that in the processing unit ( 2 ) may be detected skidding movements / vehicle rotations about the vehicle vertical axis and processed accordingly / can be considered.

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

In order that this signal, which is detected with the cosine ω z and attenuated, does not lead to an impairment / detuning of the algorithm or the triggering decision for the restraining means of a vehicle ( 1 ) occurs in the illustrated frontal or side crash scenario, in the downstream processing unit, the signal information of the directed acceleration sensor, with the rotation angle information of the yaw angle sensor ( 4 ) is compensated by multiplying the attenuated detected signal information of the directional acceleration sensors by the inverse of the cosine ωz (or dividing by the cosine ωz).

As possible crash scenarios in this representation, as not further illustrated, it is conceivable that a side crash is caused by a vehicle coming from the transverse direction or from the direction of travel, or the vehicle (FIG. 1 ) bounces even in this position against a (in the direction of travel or in the transverse direction) unspecified obstacle. Both crash scenarios are possible, for example, if, in the run-up to the actual crash, the driver of the vehicle shown ( 1 ) has tried an evasive maneuver in which the vehicle ( 1 ) has twisted around the vehicle's vertical axis as shown, or the vehicle gets out of the lane when braking for black ice or begins to turn.

4 shows the alternative possibility of the common arrangements of the directions of action of the directional accelerometer in the central unit, according to the prior art.

at the arrangement of the directional acceleration sensors according to "A", with a sensitivity characteristic of the sensors parallel to the main vehicle axes (x, y), the Sensor signals, in an undesirable Vehicle rotation around the vehicle's vertical axis, with the reciprocal of the cosine be multiplied by the angle of vehicle rotation, thus a inventive compensation the (as a result of vehicle rotation about the vehicle vertical axis) attenuated sensor signals takes place because the sensitivity direction of the directional sensors is turned off by the "crash direction" (the Angle is increased).

at the arrangement of the directional acceleration sensors according to "B", with a sensitivity characteristic of the sensors deviating from the main vehicle axes (x, y), the sensor signals, at an undesirable Vehicle turn around the vehicle's vertical axis, with the cosine of the angle the vehicle rotation are multiplied, so that a compensation according to the invention the (as a result of vehicle rotation about the vehicle vertical axis) amplified sensor signals takes place because the sensitivity direction of the directional sensors is turned to the "crash direction" (the angle is reduced). One of the arrangement "B" analog compensation is also to be carried out with the assistance sensors, if this one of the Major axes have significantly different mounting direction.

5 shows a schematic representation of the sensitivity characteristic of a directional sensor, in which the Sensier sensitivity (the sensor is correspondingly less sensitive to a single direction with the angle) as a function of the cosine of the angle of rotation decreases.

As from the illustration, the sensor has zero degrees his greatest sensitivity (100%). If the force or acceleration effect of a direction deviating from zero degrees, the sensitivity decreases of the sensor, or the ability to sense the force or acceleration effect, according to the function shown (E = f (cos angle)) in percent.

1

vehicle

2

processing unit

3.1

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

3.1.y

Sensitivity characteristic of the sensor / acceleration sensor 3.1

3.2

Sensor / Accelerometer in a front assistance sensor (x-direction)

3.2.x

Sensitivity characteristic of the sensor / acceleration sensor 3.2

3.3

Sensor / Accelerometer in a front assistance sensor (x-direction)

4

Yaw rate sensor

.omega..sub.x

angle vehicle rotation around the vehicle's longitudinal axis (x-axis)

.omega.y

angle vehicle rotation around the vehicle's transverse axis (y-axis)

.omega.z

angle vehicle rotation around the vehicle's vertical axis (z-axis)

Claims (16)

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 ) having a sensitivity characteristic following the alignment ( 3.1.y . 3.2.x ) and at least one yaw rate sensor ( 4 ), characterized in that the processing unit ( 2 ) in the triggering decision for the activation of the restraining means in a side or frontal crash, the rotational angle (ωx, ωy, ωz) of the vehicle ( 1 ) are taken into account by taking into account the yaw rate information in the triggering decision. Method according to claim 1, characterized in that that by means of the yaw rate information, arising by rotation the vehicle from its desired position, a compensation or a corrective action, on at least one the characteristic change resulting from the vehicle rotation or related quantity. Method according to claim 1, characterized in that that by means of yaw rate information, arising from rotation the vehicle from its desired position, a compensation or a corrective action, on at least one the parameter change resulting from vehicle rotation or related quantity. Method according to claim 2 or 3, characterized that compensation or corrective action by the vehicle rotation resulting characteristic change or related quantity, or resulting parameter change or related quantity, by means of a calculation rule he follows. Method according to claim 4, characterized in that that the calculation rule that in sensitivity, as a result of Vehicle turn, modified directional Acceleration signal of the acceleration sensor, according to the Vehicle rotation corrected by the acceleration information, the at the vehicle target position aligned in Crashrichtung accordingly Acceleration sensor, with the reciprocal of the cosine of the angle the vehicle rotation are multiplied when the angle of the Sensitivity direction of the acceleration sensor, due to the Vehicle rotation, has increased from the crash direction. V experienced according to claim 4, characterized that the calculation rule that in sensitivity, as a result of Vehicle turn, modified directional Acceleration signal of the acceleration sensor, according to the Vehicle rotation corrected by the acceleration information, the at the vehicle target position aligned in Crashrichtung accordingly Acceleration sensor, with the cosine of the angle of vehicle rotation multiplied when the angle of the sensitivity direction of the acceleration sensor, due to the vehicle rotation, of the Crash direction has decreased. Method according to claim 4, characterized in that that the calculation rule that in sensitivity, as a result of Vehicle turn, modified directional Acceleration signal of the acceleration sensor, according to the Vehicle rotation corrected by the acceleration information, the at the vehicle target position aligned in Crashrichtung accordingly Acceleration sensor, according to the correction values a stored table / matrix can be changed or weighted. Method according to claim 4, characterized in that that the calculation rule that in sensitivity, as a result of Vehicle turn, modified directional Acceleration signal of the acceleration sensor, according to the Vehicle rotation corrected by a calculation rule in the processing unit a correction of the integration time constant corresponding to the vehicle rotation the acceleration signals, or a corresponding correction of the Triggering thresholds, causes. Method according to one of the preceding claims, characterized characterized in that it is at the vehicle rotation to a rotation around one of the vehicle's main axes (ωx, ωy, ωz), or a combination rotation about a plurality of the vehicle main axes (ωx, ωy, ωz). 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 ) having a sensitivity characteristic following the alignment ( 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), characterized in that the processing unit ( 2 ) is adapted 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, taking into account the yaw rate information in the triggering decision. Device according to claim 10, characterized in that that this on the basis of the yaw rate information, which by rotation of the vehicle from its desired position generated, a compensation or a corrective action, at least one of the vehicle rotation resulting from the vehicle characteristic change or related quantity. Device according to claim 10, characterized in that that this on the basis of the yaw rate information, which by rotation of the vehicle from its desired position generated, a compensation or a corrective action, at least one of the vehicle rotation resulting from the vehicle parameter change or related quantity. Device according to claim 11 or 12, characterized in that that the compensation or corrective action resulting from the vehicle rotation characteristic change or related quantity, or resulting parameter change or related quantity, by means of a calculation rule he follows. Device according to claim 13, characterized in that that the calculation rule that in sensitivity, as a result of Vehicle turn, changed directed acceleration signal of the acceleration sensor, accordingly the vehicle rotation corrected, or according to the correction values of a deposited table / matrix changed or weighted, or corrected according to the vehicle's rotation, by a calculation rule in the processing unit one of Vehicle rotation corresponding correction of the integration time constant the acceleration signals, or a corresponding correction of the Triggering thresholds, causes. Device according to one of the preceding claims, characterized characterized in that the correction by multiply or divide the cosine value of the angle takes place, with this the sensitivity axis the accelerometer to the intended target crash detection direction, due the vehicle rotation, changed has been. Device according to one of the preceding claims, characterized characterized in that this one vehicle rotation by one turn around at least one of the vehicle main axes (ωx, ωy, ωz), or a combination a rotation about a plurality of the vehicle main axes (ωx, ωy, ωz) detected.