DE102005005959A1 - Device for controlling safety device of motor vehicles has control unit which is designed for adjusting colliding objects on basis of characteristic features in precrash sensor which measures signal processes which determines tripping time - Google Patents

Abstract

The invention relates to a device for controlling a safety device (18) of a vehicle, having a precrash sensor (10) which has a plurality of separately evaluable detection regions (22, 23, 24) for detecting collision objects (12, 14) and a control unit (16) for controlling the security device (18). The control unit (16) is designed to assign collision objects (12, 14) due to characteristic features in a signal course measured by the precrash sensor (10) certain object classes and the triggering time (s) and / or Auslöseintensität (s) of one or more protection means (20) of the security device (18) depending on the assigned object classes.

Description

The The invention relates to a device for controlling a safety device of a vehicle according to the preamble of claim 1 and a corresponding method according to the preamble of claim 21

to Control of a vehicle safety device such as an occupant protection system becomes the signals from acceleration sensors evaluated by having one or more predetermined Thresholds are compared. When the thresholds are exceeded become trigger signals for protective agents such as airbags or belt tensioners generated. Between the Detection of a crash-relevant acceleration of the vehicle and forming a trigger signal however, there is only a short period of time, usually a few milliseconds, which distinguishes between different accident and crash scenarios with different triggering requirements often difficult or even at all not possible.

In order to be able to better adapt the triggering of protection means to an accident scenario and thus to achieve a more efficient use of protection means, the relative speed measured between a vehicle and the collision object, for example by means of a precrash sensor, can be evaluated and used to adapt triggering thresholds of protection means. Further improvement of the safety device efficiency can be achieved by classifying collision objects and adapting the use of protection means accordingly. For example, this describes EP 1 409 296 A1 a method that classifies objects based on acceleration signals derived from precrash sensor data and their time derivative. WO 2004/033260 A1 also discloses a device in which the triggering of a second airbag stage of a multi-stage airbag is dependent on the acceleration and a measured impact speed. A more detailed classification is from the DE 102 351 64 A1 which describes a method which can detect a collision with a pile from the signal profiles of a precrash sensor and acceleration sensors.

A For example, a particularly accurate classification of collision objects achieved with a camera and a corresponding image processing become. Such a solution However, it is technically very complicated and therefore expensive. A low cost Precrash sensor owns for such a precise classification does not provide the required resolution and is therefore not suitable as a camera replacement.

task The present invention is now, a device and a Method for controlling a safety device of a vehicle to propose a classification of collision objects by means of a Enable precrash sensors.

These The object is achieved by a device for controlling a safety device a vehicle with the features of claim 1 and by a corresponding Method solved by the features of claim 21. Preferred embodiments The invention will become apparent from the dependent claims.

One essential idea of the invention is objects due characteristic features in a measured by a precrash sensor Signal waveform attributable to certain object classes and the triggering time and / or Triggering intensity of one or more protection means of a security device depending on to set the assigned object classes.

The The invention now specifically relates to a device for controlling a Safety device of a vehicle, with a precrash sensor, which has a plurality of separately evaluable detection areas for detection of collision objects and a control unit for controlling the security device. The control unit is designed to collision objects due characteristic features in a measured by the precrash sensor Signal waveform attributable to certain object classes and the triggering time and / or tripping intensity of a or more protection means of the security device depending on to set the assigned object classes.

Preferably, the precrash sensor has three separately evaluable detection areas, for each of which a distance value between a collision object detected in the respective detection area and the Vehicle can be determined. It has been shown that with three detection ranges a sufficiently accurate classification of collision objects is possible with a relatively low technical outlay.

The Above all, the control unit can be designed to be used in several Detection areas of the precrash sensor detected collision objects the for each distance detected with each other compare and classify the collision objects as an object, if the determined distance values within a given Tolerance range are. The tolerance range can be empirical, for example be determined.

Especially can for the Object classes and detection areas distance ranges to be set in which a detection of a collision object is expected.

The Object classes can dependent on this on the geometry of the detection areas and relevant collision objects chosen be.

Farther For example, the control unit may be configured to be at one in a particular one Combination of detection areas and in a certain distance range Detected collision object an object indicator for one or to set several object classes.

Instead of of distance ranges can also for each object class probability functions be set the determined distance value of a collision object and the Combination of the recording areas as input quantities and the recognition probability of the respective object class as output Size has.

Further the control unit may be designed to display object indicators and / or Recognition probabilities of a qualification, integration and / or filtering to obtain as exact a classification result as possible to achieve.

The Control unit can also be designed to at the time of actual Collision and / or in a definable time or distance window the individual assigned object classes with regard to their quality index, Integrals or filter output compare and the most likely Select object class as relevant and spend.

typically, The object classes include an approximately frontal collision with a Pile and a wall, a collision with a wall at an oblique angle and a collision with a laterally offset obstacle.

In addition to the object classes can be provided a separate class, the Includes objects that have a distance shorter than an outer dimension of a vehicle. Such objects may e.g. a truck (lorry) subways or vehicle-pedestrian collisions, where the upper body or head of the pedestrian already partly over the hood of a vehicle is located.

The Control unit may also be designed to one or more criteria to monitor which the assignment of an object class to a collision object with an insufficient Prevent confusion. This increases the safety of one Misclassification.

One Criterion can be as possible Criterion e.g. a minimum value of a relevant object class and / or a minimum difference of a relevant to all other object classes include.

In a preferred embodiment The control unit is designed to have a limited selectivity between the detection areas of the precrash sensor when assigning a To consider a collision object for an object class. This can be done increase the accuracy of the classification.

Farther the control unit may be designed to provide a tolerance of measured distance of a collision object in the assignment of the Collision object to consider an object class, which also the accuracy of the classification can be increased.

In the control unit, a parameter can be stored, which is adjustable to the distance in which a collision between the vehicle and collision object is to be expected. This distance can be, for example the distance between the precrash sensor and a central location of the bumper of the vehicle.

Preferably the distance is dependent adjustable from the angle, under which a potential collision object can be detected by one or more Crahssensoren. Thereby can different collision distances for example straight and oblique Considered collisions which result from the geometry of the bumper or the vehicle.

The Control unit can also be designed to be a collision object associated object class and / or orientation of the capturing Detection area for to use the selection of further data of the precrash sensor.

Of the Precrash sensor can be based on the principle of a radar, laser or Ultrasonic sensors work, with a runtime and / or frequency / phase shift detected between a transmitted and a received signal becomes.

Finally, can the control unit be designed such that the triggering time and / or Triggering intensity of one or more protection means of the safety device in a Object class with a low initial acceleration in the Collision case such as a central pole or a deformable one Barrier advanced or increased and for an object class with a high initial Acceleration in case of collision such as a wall delayed or attenuated or the triggering dependent on other criteria completely suppressed becomes.

The The invention further relates to a method for controlling a security device of a vehicle in which a precrash sensor, several separated has evaluable detection areas detected collision objects. The collision objects become due to characteristic features determined in a waveform measured by the pre-crash sensor Assigned object classes and the triggering time and / or tripping intensity of one or more protection means of the security device depending on set the assigned object classes.

Further Advantages and applications The present invention will become apparent from the following description in conjunction with the embodiments illustrated in the drawings.

In the description, in the claims, in the abstract and in the drawings are those in the listed below List of reference numbers used terms and associated reference numerals used.

The Drawings show in:

1 in a plan view, the detection of a frontal collision with a wall by a precrash sensor with three detection areas;

2 in a plan view, the detection of a frontal collision with a pile by a pre-crash sensor with three detection areas;

3 in a plan view, the detection of a collision with a wall at an oblique angle by a pre-crash sensor with three detection areas;

4 in a plan view, the detection of various collisions with a laterally offset to the longitudinal axis of a vehicle pole (a) and b)) and with a laterally offset to the longitudinal axis of a vehicle wall (c) and d)) by a precrash sensor with three detection areas;

5 in a plan view, the detection of a collision with an already penetrated into the vehicle structure pile (a)) and an already penetrated into the vehicle structure wall (b)) by a pre-crash sensor with three detection areas; and

6 a vehicle with a device for controlling a safety device according to the invention.

in the following can the same and / or functionally identical elements with the same reference numerals be.

1 shows in plan view a detection of a frontal collision with a wall 12 through a precrash sensor, which has a first, right detection area 22 , a second, left detection area 24 and a third, middle, that is arranged between the first and second detection area detection area 23 having. The three coverage areas 22 . 23 and 24 can overlap, which affects the selectivity between the detection areas of the precrash sensor. The precrash sensor can be used to detect whether and at what distance from the precrash sensor a collision object is located.

In 1 is a wall as a collision object 12 shown approaching the front of a vehicle with the precrash sensor. The wall 12 will be in all three coverage areas 22 . 23 and 24 detected at approximately the same distance. As a result, an unillustrated control unit arranges the signals in the three detection ranges by corresponding processing of the signal course measured by the precrash sensor 22 . 23 and 24 detected objects a single, wide collision object 12 to.

In 2 is a frontal collision with a pole 14 shown as a collision object. Here is only in the middle coverage area 23 a collision object detected. Therefore, due to the corresponding signal curve measured by the precrash sensor, the control unit arranges that in the detection area 23 detected object as a single narrow collision object such as a pole or a tree.

3 shows a collision with a wall 12 at an angle. This will be back in each of the three coverage areas 22 . 23 and 24 each detected an object, but each with different distances. In the left in 3 The scenario presented is in the coverage area 22 an object at a distance d1 detected in the detection area 23 an object at distance d2 and in the detection area 24 an object at distance d3. The following applies for the distances: d1 <d2 <d3. The control unit now processes the signal curve measured by the precrash sensor by first comparing the measured distances with one another. If the measured distances lie within a predetermined distance range or have values as explained above, it can be assumed with high probability that three objects become a single collision object 12 belong. Due to the distances d1 and d3, the control unit can also determine the angle at which the collision object is located 12 ie the wall approaches the precrash sensor. Such information is used in the control unit to set the trip time (s) and tripping intensity (s) of protection means such as airbags. For example, the deployment of an airbag in the event of a collision with a wall 12 , as in 3 indicated, delayed in time and attenuated the intensity, for example, by the gas generator is controlled accordingly for the airbag.

4 shows collisions with laterally to the longitudinal axis of the precrash sensor and thus of the vehicle in which the precrash sensor is arranged, offset collision objects. In 4a ) and b) is a stake 14 as a collision object so laterally offset that it is in the first, right and second, left detection area 22 respectively. 24 of the precrash sensor is located. The control unit therefore classifies the pile as a narrow collision object that is laterally offset. In 4c ) and d) is another vehicle 12 is laterally offset as a collision object and is used by the precrash sensor in the first, right and middle detection areas 22 and 23 ( 4c )) or in the second, left and middle detection area 24 and 23 ( 4d )) detected. Due to the same distance in both detection areas 22 and 23 respectively. 24 and 23 becomes the other vehicle 12 classified as a single collision object that is laterally offset. The classification can again be used to adjust the triggering of a protection means, for example by triggering protection means on the side of the vehicle early and with high intensity, on which the collision object is located.

Finally shows 5 another stake 14 ( 5a )) or a structure of another vehicle 12 ( 5b )) as a collision object, the or already in the structure of a vehicle 26 has penetrated or is located above the structure of a vehicle. Even in such cases, the precrash sensor can still provide evaluable information for the use of protection means, for example, in which direction the collision object moves when penetrating into the vehicle structure, as well as the time and the depth of penetration or overlapping.

6 shows a vehicle 26 in side view with a schematically illustrated device for controlling a safety device 18 that has a precrash sensor 10 mounted in the area of the rearview mirror in the vehicle interior and detecting the area in front of the vehicle, anda control unit 16 for controlling the safety device, in the present case an airbag system with an airbag 20 includes.

The control unit not only receives a signal from the pre-crash sensor 10 for evaluating and corresponding control of the airbag, but also, for example, from a crosstalk sensor 28 in the area of the bumper, which directly detects a crash. The control unit comprises further acceleration sensors 30 for crash detection, preferably in the vicinity of the vehicle's center of gravity.

In the following, an exemplary embodiment of the assignment of collision objects to object classes is illustrated by means of the signal course measured by the precrash sensor, as for example according to the invention by an algorithm implemented in the control unit for evaluating and processing the signal course measured by the precrash sensor can be made:

Everyone Object class can now turn in the control unit a specific Mission plan for Protective means such as airbags, belt tensioners or the like provided be. For example, it may be specified that the object class 4a or 4b right or left in the vehicle arranged side airbags early with high intensity triggered and the side airbags left or right in the vehicle not triggered become. In object class 5a and 5b, it may be specified that Belt tensioners immediately and all in the front of the vehicle existing airbags are activated immediately with high intensity.

The Invention allows So overall a much more flexible and better at an accident adapted use of preservatives using a low-cost Pre-crash sensor.

10

Pre-crash sensor with three detection areas

12

collision object Wall or vehicle

14

collision object stake

16

control unit for controlling a safety device

18

Airbag Safety System

20

air bag

22

first, right detection area of the precrash sensor 10

23

third, middle detection range of the precrash sensor 10

24

second, left detection area of the precrash sensor 10

26

vehicle

28

crash sensor

30

accelerometers

Claims (21)

Device for controlling a security device ( 18 ) of a vehicle, with a precrash sensor ( 10 ), which contains several separately evaluable detection areas ( 22 . 23 . 24 ), for the detection of collision objects ( 12 . 14 ) and a control unit ( 16 ) for controlling the security device ( 18 ), characterized in that the control unit ( 16 ) is designed to collision objects ( 12 . 14 ) due to characteristic features in one of the precrash sensor ( 10 ) assigned to certain object classes and the triggering time (s) and / or tripping intensity (s) of one or more protection means ( 20 ) of the security device ( 18 ) depending on the assigned object classes. Apparatus according to claim 1, characterized in that the precrash sensor ( 10 ) three separately evaluable detection areas ( 22 . 23 . 24 ), for each of which a distance value between one in the respective coverage area ( 22 . 23 . 24 ) collision object ( 12 . 14 ) and the vehicle ( 26 ) can be determined. Device according to claim 1 or 2, characterized in that the control unit ( 16 ) is designed to be used in several detection areas ( 22 . 23 . 24 ) of the precrash sensor ( 10 ) detected collision objects ( 12 ) for each coverage area ( 22 . 23 . 24 ) and the collision objects as an object ( 12 ), if the determined distance values lie within a predetermined tolerance range. Apparatus according to claim 1, 2 or 3, characterized in that for the object classes and detection areas ( 22 . 23 . 24 ) Distance ranges are defined in which a detection of a collision object ( 12 . 14 ) is expected. Apparatus according to claim 4, characterized in that the object classes depending on the geometry of the detection areas ( 22 . 23 . 24 ) and relevant collision objects ( 12 . 14 ) are selected. Device according to claim 4 or 5, characterized in that the control unit ( 16 ) is designed to be used in a particular combination of detection areas ( 22 . 23 . 24 ) and in a certain distance range detected collision object ( 12 . 14 ) set an object indicator for one or more object classes. Apparatus according to claim 1, 2 or 3, characterized in that for each object class probability functions are defined, which determine the determined distance value of a collision object ( 12 . 14 ) and the combination of the coverage areas ( 22 . 23 . 24 ) as input quantities and the recognition probability of the respective object class from output variable. Device according to one of the preceding claims, characterized in that the control unit ( 16 ) is configured to subject object indicators and / or recognition probabilities to qualification, integration and / or filtering. Apparatus according to claim 8, characterized in that the control unit ( 16 ) is adapted to compare the individual associated object classes with regard to their quality index, integral or filter output at the time of an actual collision and / or in a definable time or distance window and to select and output the most probable object class as relevant. Device according to one of the preceding claims, characterized characterized in that the object classes an approximately frontal collision with a pole and a wall, a collision with a wall in the oblique angle and a collision with a laterally offset obstacle. Device according to claim 10, characterized in that that in addition a class is provided for the object classes, which comprises objects, which have a distance that is shorter than an outer dimension of a Vehicle is. Device according to one of the preceding claims, characterized in that the control unit ( 16 ) is configured to monitor one or more criteria that determine the association of an object class with a collision object ( 12 . 14 ) with an insufficient statement security. Device according to claim 12, characterized in that that a criterion is a minimum value of a relevant object class and / or a minimum difference of one relevant to all others Includes object classes. Device according to one of the preceding claims, characterized in that the control unit ( 16 ) is designed to provide a limited selectivity between the detection areas ( 22 . 23 . 24 ) of the precrash sensor ( 10 ) when assigning a collision object ( 12 . 14 ) to consider an object class. Device according to one of the preceding claims, characterized in that the control unit ( 16 ) is adapted to a tolerance of a measured distance of a collision object ( 12 . 14 ) during the assignment of the collision object ( 12 . 14 ) to consider an object class. Device according to one of the preceding claims, characterized in that in the control unit ( 16 ) a parameter is stored which is based on the distance in which a collision between the vehicle ( 26 ) and collision object ( 12 . 14 ) is to be set is adjustable. Apparatus according to claim 16, characterized in that the distance is adjustable in dependence on the angle, below which a potential collision object ( 12 . 14 ) of one or more crawler sensors ( 28 ) can be detected. Device according to one of the preceding claims, characterized in that the control unit ( 16 ) is adapted to a collision object ( 12 . 14 ) associated object class and / or an orientation of the detecting coverage area ( 22 . 23 . 24 ) for the selection of further data of the precrash sensor ( 10 ) to use. Device according to one of the preceding claims, characterized characterized in that the precrash sensor according to the principle of Radar, laser or ultrasonic sensor works, with a runtime and / or Frequency / phase shift detected between a transmitted and a received signal becomes. Device according to one of the preceding claims, characterized in that the control unit ( 16 ) is designed such that the triggering time and / or tripping intensity of one or more protection means ( 20 ) of the security device ( 18 ) is advanced or increased in an object class with a low initial acceleration in the event of a collision such as a central pole or a deformable barrier, and in an object class with a high initial acceleration in the event of a collision like ei ner wall delayed or attenuated or the triggering in response to other criteria is completely suppressed. Method for controlling a security device ( 18 ) of a vehicle in which a precrash sensor ( 10 ), which contains several separately evaluable detection areas ( 22 . 23 . 24 ), collision objects ( 12 . 14 ), characterized in that the collision objects ( 12 . 14 ) due to characteristic features in one of the precrash sensor ( 10 ) are assigned to certain object classes and the triggering time (s) and / or triggering intensity (s) of one or more protection means ( 20 ) of the security device ( 18 ) depending on the assigned object classes.