DE102007021700A1 - Protection system for vehicle occupants compares the seat belt extension with the vehicle dynamics to generate control signals for the protection modules - Google Patents

Abstract

A protection system for vehicle occupants monitors the seat belt extension with the vehicle dynamics to generate control signals for the protection modules, e.g. airbag, seat belt lock etc. The control monitors the rate of change of seat belt extension, the seat occupancy, and the basic vehicle speed etc. The control system uses a map combining the different parameters and includes a driver warning system. The basic parameters are established a set interval after applying the seat belts.

Description

State of the art

The The invention relates to a method and a control device for Control of personal protective equipment for a vehicle.

From the DE 102 50 732 D3 is a control device for controlling an occupant and / or partner protection with the aid of driving dynamics known, which determines a safety-critical driving behavior of the vehicle and thus preventively reversible occupant protection issue activated. From the DE 103 33 990 A1 a device is known which recognizes a critical driving situation on the basis of speeds at accelerations and then activates restraint means. From the DE 102 46 055 A1 It is known to detect and estimate the occupant's occupant trajectory by means of force measuring pins or other interior sensor systems and to use it by means of a sensor system on the basis of accelerations in the lateral as well as in the longitudinal vehicle direction in order to trigger restraint means. From the DE 103 46 625 A1 It is known to measure the belt extension length in order to determine the occupant position of a vehicle occupant. The temporal behavior of the belt extension length is observed.

Disclosure of the invention

The inventive method or the invention Control device for controlling personal protection devices for a vehicle have the advantage that the belt extension length information is secured by a Fahrdynamikin formation. Through this Linking can improve the quality of the webbing length information can be significantly improved or it can be inaccurate and thus cheaper sensors are used. This can be the Forward displacement of the occupants can be determined more accurately and thus the personal protection means are improved. Thereby you can achieve a customized for each occupant Activation of its retention agent depending on his state of motion relative to the vehicle. Furthermore can also use this link a derivative are carried out on the seat mass, there by means of the belt extension consignment and acceleration the mass can be estimated. This can be a Perform belt classification, which may be an interior sensor sensor makes the classification of inmates superfluous or at least as a plausibility check for such an interior sensor system can serve.

The inventive method or the invention Control unit can also work on existing interfaces fall back, so that the effort to realize the invention is limited.

The Determining the forward displacement of the vehicle occupant according to the invention requires only one low computational and storage performance, since the state in particular must be calculated when a braking maneuver occurs.

present is under a control unit to understand the function that sensor signals are processed and dependent on the sensor signals, a drive signal is generated. That's it possible that in the control unit itself too Sensors are located. An integration of all possible components is possible. So it is also possible that the control unit, which drives the belt, includes all the functions of the invention. Also a safety control device that is active and passive Passenger protection means is possible.

Under Control is the activation of personal protection equipment to be activated such as airbags, belt tensioners, switchable belt force limiters, brakes, crash-active headrests, roll bars, seat-integrated systems (eg anti-submarining), etc. understand. An activation can also be the activation of warning devices mean like visual scoreboards or audible beeps.

Under The belt extension length information is all possible To understand signals and their derived quantities which can be determined from the belt extension length, so z. B. the belt pullout speed, the belt pullout acceleration, local and / or global gradients of these quantities, maxima, Minima and / or averages and / or integral values.

Under The driving dynamics information is all possible signals and derived variables to understand the can provide a vehicle dynamics control. These include accelerations in all spatial directions, rotation rates around all spatial axes, steering angle information, Information about the pedals, speed information the wheels and derived variables like a vehicle speed, information about that Engine management (gait), brake information such as brake pressure and / or individual brake pressures applied to the wheels, brake activation and derived quantities. If necessary, you can in this case also information from a forward-looking sensor such as radar, video, lidar, and / or ultrasound.

Interior information is to be understood as meaning all possible signals and variables derived therefrom which interior sensor technology can supply. These include seat occupancy detection and / or occupant classification and / or occupant identification (eg occupant age and / or occupant gender classification), buckle status, and / or belt force, seating position in all three spatial directions, and seat tilt and sizes derived therefrom.

Under a link are all possible ones Conceivable methods such as summation or difference formations, correlations, Mean value etc. Hedging here means that the belt extension length information but is used as such by the vehicle dynamics information checked for accuracy and plausibility becomes.

The In the present case, interfaces are hardware and / or software-based educated. The interfaces can therefore on a Microcontroller as a software element or as an integrated circuit or consist of a plurality of integrated circuits. Also a discrete structure of such an interface is possible.

Under the evaluation circuit are preferably a microcontroller but to understand other processor types. One more way are user-specific integrated circuits or discrete ones Solutions or combinations of these possibilities. A parallelization of the calculation to several microcontrollers is also possible.

By those listed in the dependent claims Measures and developments are advantageous improvements of the specified in independent claims Method or control device for controlling personal protection devices possible for a vehicle.

Advantageous is that as a belt pullout information, a belt extension speed and as vehicle dynamics information, an airspeed of the vehicle can be used, where the link is achieved by subtraction and integration. It can difference formation and integration in the process be exchanged in time, d. H. it can either be the difference the own speed and the belt pull-out speed integrated or the belt pullout speed and the airspeed are each integrated and then follows the difference.

It is also advantageous to provide a linkage of the belt extension length and the forward displacement in the longitudinal direction. A possible link takes into account the geometric relationship between the excerpt and the forward displacement, which can be taken into account in a characteristic curve. The following general rule can be used, for example, for the quotient of belt extension length and forward displacement in the vehicle longitudinal direction as well as for the quotient of belt extension speed and forward displacement speed (initially vehicle speed):

there a, b, c and d denote freely selectable parameters and t the time course. This can be further parameters as the seating position to improve the accuracy of this occupant forward displacement determination be used. The seating position can preferably be used for this purpose be to parameterize the characteristic field, d. H. for different Seat positions have different parameterized characteristic curves. The characteristics are in a dedicated storage medium filed and retrievable.

It is further advantageous that the link through a Characteristic field is reached. The belt extension length information and determine the vehicle dynamics information, which point of the characteristic curve is used to determine, for example, occupant advancement.

Favorable Way, depending on the linkage Also, a warning will be issued to the driver. Already can be warned in an apron of the actual accident the driver to take any countermeasures.

Favorable Way can from the temporal behavior after the fastening process the belt extension length defines a basic value for the belt extension length Then, the Gurtauszugslängeninformation depending on of this basic value. This will become typical behaviors of a vehicle occupant takes into account a correct To get the basic value. This allows a high accuracy the method according to the invention.

Advantageously, a distance measure obtained in the longitudinal direction relative to a belt pullout point is determined for the further processing of the belt extension length information. This value can be further processed directly, while usually the Gurtauszugslängen is detected via an incremental encoder on the winding shaft. This incremental encoder provides a measure of the number of revolutions of the winding shaft. By way of example, an incremental encoder is used which has a resolution of 9 °. The value supplied by the incremental encoder thus corresponds to the number of winding shaft revolutions and must be converted according to its resolution, so that an extension length specification in meters is available. In a first approximation, however, the number of Wi ckelwellenumdrehungen the extension length is set directly proportional to the extension length. By a characteristic stored in the control unit according to the invention, the value of the incremental encoder can be transformed directly into length information.

It is also advantageous that as the vehicle dynamics information a Activation of a brake light switch or a gradient of a brake pressure used and depending on the belt extension length intended to determine a forward displacement of a vehicle occupant becomes. This can be checked in particular when and how a braking maneuver is initiated. The use of the brake light switch indicates whether the driver is currently initiating a braking maneuver. The gradient of the brake pressure provides a statement about How much the driver initiates the braking maneuver. exceeds this gradient has a corresponding threshold, so can the the characteristic determined forward displacement information accordingly be watched, filtered or stored. This signal will further transmitted either directly to the airbag control unit or in a preferred variant by an independent Signal path made plausible. The independent signal path takes this into account through integration and subtraction obtained signal from vehicle and belt extension speed. This Signal is sent with the forward displacement information determined from the characteristic field linked and secured.

Under a link are all possible ones Conceivable methods such as summation or difference formations, correlations, Mean value, etc. Hedging here means that the linked signal is checked against a threshold.

embodiments The invention are illustrated in the drawings and in the explained in more detail below description.

It demonstrate:

1 a block diagram of the control device according to the invention with connected components,

2 a flow chart of the method according to the invention,

3 a signal flow diagram,

4 another signal flow diagram,

5 a belt pullout length time chart,

6 a forward displacement time diagram,

7 another signal flow diagram and

8th a block diagram.

1 shows a block diagram, the control device SG according to the invention in a vehicle FZ with connected components. Shown here as well as in the other figures, only the components that are necessary for understanding the invention. Other components necessary for operation in general are not shown for the sake of simplicity.

At the control unit SG are a belt control unit G and a vehicle dynamics control unit ESP connected. It is possible that more than one belt controller available. The belt controller G provides the belt extension length information to the control unit SG and is in an interface IF1 connected in the control unit SG. the interface IF1 is in the present case designed as an integrated circuit.

The Interface IF1 transmits the data from the belt control unit G to a microcontroller μC as the evaluation circuit. The vehicle dynamics control unit ESP transmits its data to the control unit SG and thereby to an interface IF2, also as an integrated circuit in the control unit SG is formed. The interface IF2 also transmits the data from the vehicle dynamics control unit to the microcontroller μC.

On the microcontroller .mu.C runs the inventive Procedure. The microcontroller μC linked the belt extension length information with a vehicle dynamics information, such that the belt extension length information is provided by the vehicle dynamics information is secured. This means, as shown above, one Accuracy improvement or a plausibility check. The link can, as shown above, performed in various ways become.

The The result of this link is used to control the personal protective equipment like an airbag used, so depending on the forward displacement of the airbag can be adjusted adapted. For the actual triggering are additional Accident signals, for example, from an acceleration sensor provided to evaluate such a trigger case to recognize.

A simple way to create a link is a subtraction with subsequent integration of the difference. This provides, when the vehicle dynamics information is the intrinsic speed of the vehicle, a differential speed, which after integration the relative Forward displacement of the occupant to the vehicle describes. The microcontroller .mu.C generates a drive signal and transmits it, for example, via the controller-internal bus SPI (Serial Peripheral Interface Bus) to the drive circuit FLIC, which likewise consists of integrated circuits, wherein different power switches are present on the individually integrated circuits. The drive circuit FLIC then ensures that, as a function of the drive signal, personal protection means are activated, ie activated.

Depending on the link, however, the microcontroller .mu.C can also output a warning. For this purpose, the microcontroller uses μC interface IF3, which is also designed as an integrated circuit in the control unit SG. This interface IF3 transmits to a display located outside of the control unit SG 100 the signals are then displayed there. This can be pointed in particular to a dangerous attitude of the vehicle occupants.

2 shows in a flow chart an example of the inventive method. In process step 200 For example, the belt extension length information is provided for the belt extension speed. In process step 201 For example, the vehicle dynamics information is provided to the vehicle's own vehicle speed. In process step 202 the link is in this case a subtraction with subsequent integration. This is then the relative forward displacement 203 in front. This gets into an algorithm 205 given, which then decides whether the personal protection should be controlled or not. For this purpose, the algorithm additionally uses the impact signals 204 , If a triggering case is detected, then is in process step 206 an activation of the personal protection means made. However, if no accident has been detected, the method ends in process step 207 ,

3 shows a signal flow diagram illustrating the combination of the vehicle dynamics signal and the Gurtauszugslängeinformation. In block 300 the belt pullout speed is provided and in block 301 the own speed, which is provided by the vehicle dynamics control. This is through the block 302 a difference is formed, so that then there is a difference speed Δv. This one is in block 304 integrated, so in block 305 the relative forward displacement of the vehicle occupant relative to the vehicle is present.

4 shows an alternative. In block 400 In turn, the Gurtauszugslängegeschwindigkeit is provided and in block 401 the airspeed. Both sizes are each in the blocks 402 and 403 integrated then in block 404 to form a difference. The result is in turn the relative forward displacement of the vehicle occupant relative to the vehicle δs in block 405 ,

5 shows a Gurtauszugslängendiagramm. In a seat belt, each occupant experiences a typical extension length for him, which is additionally dependent on the position of the seat relative to the instrument panel and the person, ie the body proportions. Considering such a buckling process, as indeed through the curve 502 is shown, there is an underlying 501 in a temporary state of rest. The person performed after snapping the buckle a forward displacement in the X direction, as denoted by the reference numeral 500 is shown and this forward displacement then reduced then back to the underlying 501 ,

6 shows a characteristic field for the quotient of forward displacement and Gurtauszugslänge as a function of time for a defined seating position setting. The individual curves 600 . 601 and 602 indicate three different occupant geometries (female 5%, male 50% and male 95%).

From the characteristics in 6 can be generated by the seat position parameterized characteristic field, which depends in three-dimensional space from above quotient, the occupant size and the seat position setting. The seat position adjustment is either via a switch or continuously recorded or provided by an interior sensor. With the belt classification of the person determined in advance and the seat position associated therewith, it is now possible to determine a value via the characteristic field which, with the aid of the belt extension length, gives a value for the forward displacement of the occupant relative to the seat backrest. This value is influenced by the movement of the occupant and can be monitored according to the invention with the help of dynamic driving variables.

Using the vehicle dynamics data can be checked when a braking maneuver is initiated. One possible embodiment provides for the use of the brake light switch, since this provides the information as to whether the driver is currently initiating a braking maneuver. Alternatively, the gradient of the brake pressure can be used. This provides a statement about how much the driver initiates the braking maneuver. If this exceeds a corresponding threshold value, the forward displacement information determined from the characteristic curve can be correspondingly observed, filtered or stored. This signal is transmitted either further directly to the airbag control unit or in a preferential variant stabilized by an independent signal path. The stabilization takes place via the independent path of the integral formation over excerpt and vehicle speed, as it is to the 3 and 4 has been described.

7 shows another signal flow diagram. In the process step 700 the gradient of the brake pressure is provided, the in process step 701 is compared with a threshold. In process step 702 then the correction of the characteristic value takes place in dependence on the result of the threshold value check. This is in process step 703 the forward displacement, then in triggering algorithm 704 received as input date.

Alternatively, in process step 705 the acceleration of the vehicle are provided in the longitudinal direction. This can be used as an alternative signal in a process step 701 be compared with a threshold. Subsequently, the forward displacement is determined as in the method steps 702 . 703 and 704 described.

A Combination of gradient of brake pressure and acceleration of the vehicle as a control signal for determining the Vorverlagerungsinformation is also possible.

By The incremental encoder is obtained with a passenger delay z. B. a brake maneuver the belt extension speed. Also obtained from a vehicle dynamics control system Speed of the vehicle, for example via the CAN bus. From this, the differential speed of the occupant can be calculated determine relative to the vehicle. By integrating this size you get the relative displacement of the occupant.

The Integration of the individual terms, ie the vehicle speed and the occupant speed with subsequent relative value formation allowed an alternative evaluation algorithm.

Other Speed sensors such as optical sensors via Basic or GPS systems or navigation systems are also possible.

In Another alternative is the deceleration of the vehicle in the longitudinal direction by means of an acceleration sensor in recorded lower acceleration range. So that can be on the vehicle and then on the occupants during the delay be determined. If one uses an initial speed, the z. B. can be on the tachometer signal, so can be over a first integration to determine the speed of the vehicle and you proceed as described above and thus leaves about the belt pull-out speed and the vehicle speed also determine a value for the forward displacement. This regardless of the method described above Value can be used as a plausibility signal and serves to stabilize the forward displacement determination, which alternatively via a characteristic field is obtained.

Other Variants to determine the belt extension speed, for example via optical methods or electromagnetic detection are also possible. Also a capacitive method where the capacity between in and failed belt a measure of represents the extract, can be used.

8th shows an embodiment of the invention. In this case, no vehicle longitudinal delay is used. The calculation can be done in the airbag control unit or on the other control unit. The transmission of the sensor signals can be done via a bus system or a direct reading of the sensor information in the corresponding control unit. The storage principles for the memory used can be mechanically, optically, magnetically, electromagnetically formed on a wide variety of bases.

Other Systems such as optical warning systems can also be based be driven by this information to the inmates one Send feedback about his position. For this also include acoustic or haptic warning systems. Because the Belt extension length monitored for all occupants can be calculated for each used in the vehicle Sitting position an individual forward displacement information. These can also be used in other restraint system generations different retention strategies are used.

The belt extension length sensor 800 gives its signal to a filter 801 , The signal may be an analog signal which is digitized in a further preliminary stage. An alternative advantageous variant is a processed digitized signal which represents a dimensionless signal which is in high correlation with the belt extension length. An alternative, advantageous variant is a processed digitized signal which describes the belt extension based on the physical unit meters. In process step 801 the filtering of the input signal takes place. An advantageous variant of the filtering provides a low-pass filtering of the signal with the order 1 in front. Alternative filters as well as cascades of filters are also conceivable.

The output signal of the filter 801 becomes a classification 802 supplied to perform the above-mentioned pressure classification. This classification can be done via the CAN bus 803 also to other vehicle systems, such as comfort systems be made accessible. The classification is in a memory 821 stored. The output signal of the filter 801 However, it is also a memory 810 in which also the output signal of an AND gate 806 that checks whether a belt buckle sensor or switch 804 indicates that the belt 805 is stuck and that the speed in the vehicle longitudinal direction, the driving dynamics system 807 is provided, smaller than a predetermined threshold 808 is. That in block 810 stored signal serves as the base value for the belt extension length. The control signal is the block 806 logically linked output signal.

The vehicle dynamics system provides output signals to the threshold comparator 809 which determines the gradient of the brake pressure and compared with a predetermined threshold value. The signal thus determined serves as a control signal for the method step 812 , which as an additional input signal, the forward displacement in the longitudinal direction of block 818 receives. Furthermore supplies the driving dynamics system 807 the airspeed leading to a subtractor 813 is supplied, in which the speed is received in the vehicle longitudinal direction. The difference is in block 816 integrated and from the process 817 used for plausibility. The in process step 817 to plausibilizing input signal is from the process step 812 won. As input signal for the procedural step 812 serves the Vorverlagerungssignal obtained via the characteristic field, in the process step 818 is determined.

In the block 823 the seat position is determined and depending on this, a value from the memory 822 determined as an input signal for offset determination in the block 820 serves. In block 802 an occupant classification is performed. Depending on the thus determined occupant class, a value is stored in the memory 821 determined, as another input signal in the block 820 to correct an offset. In block 820 the two will be out of the stores 821 and 822 linked values. The link can include an addition or subtraction and is used to correct the in process step 810 stored base value for the belt extension length. The output signal from block 811 becomes the procedural step 811 fed. This determines via a characteristic field the forward displacement in the longitudinal direction of the occupant, which represents the function value that results when the input signal from block 811 is used as an argument.

In block 819 is then the plausibilisiert forward displacement by the airbag algorithm and thus enters into the decision whether the personal protection means should be controlled or not.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 10250732 D3 [0002]
• - DE 10333990 A1 [0002]
• - DE 10246055 A1 [0002]
• DE 10346625 A1 [0002]

Claims (8)

Method for controlling personal protective equipment (PS) for a vehicle (FZ), wherein the control is carried out in dependence on a belt extension length information, characterized in that for the control, the belt extension length information is linked to a vehicle dynamics information such that the belt extension length information is secured by the vehicle dynamics information. Method according to claim 1, characterized in that in that the belt extension length information is a belt extension speed and as the vehicle dynamics information, an airspeed of the vehicle be used, the link through a difference and an integration is achieved. Method according to claim 1 or 2, characterized that the linkage reaches through a characteristic field becomes. Method according to claim 3, characterized that the characteristic field is parameterized by a seating position. Method according to one of the preceding claims, characterized in that depending on the linkage a warning is issued to the driver. Method according to one of the preceding claims, characterized in that after the buckling process in dependence from a temporal behavior of the belt extension length Basic value for the belt extension length determined is, the Gurtauszugslängeinformation depending on is generated by this basic value. Method according to claim 3, characterized the vehicle dynamics information is an activation of a brake light switch or a gradient of brake pressure is used and depending of which the belt extension length for determining a forward displacement a vehicle occupant is determined. Control device for controlling personal protective equipment (PS) with: A first interface (IF1), the provides a strap length information, - one second interface (IF2), which provides vehicle dynamics information, - one Evaluation circuit (μc), for the control the belt extension length information and the vehicle dynamics information linked such that the Gurtauszugslängeninformation is secured by the vehicle dynamics information.