JP6698264B2 - Vehicle collision evaluation method and device and computer program - Google Patents

Description

  The invention relates to a vehicle collision identification method, a corresponding device, a corresponding vehicle collision evaluation system and a corresponding computer program product.

  To detect pedestrian accidents, hitherto mainly sensor systems based on two or more acceleration sensors and incorporated in bumpers have been used.

  Further, in order to detect a vehicle accident, an airbag control device which is generally arranged in a center tunnel is used. The algorithms used to detect frontal crashes or frontal collisions are mainly based on acceleration signals in the x-direction of the vehicle or in the driving direction. This acceleration sensor is generally located in the central airbag control device, but can be mounted externally. The challenge for the above-mentioned trigger algorithm is, in particular, to distinguish between fast crashes on soft obstacles and slow crashes on hard obstacles. During a fast crash into a soft obstacle, the restraint means should be activated, but the acceleration values measured by the time of the trigger are small. At low speed impacts on hard obstacles the restraint should not be activated, but the measured acceleration is high. To reliably distinguish between these collision types, additional sensor systems, such as upfront sensors, are often used.

  An object of the present invention is to provide a vehicle collision evaluation method and apparatus and a computer program that more reliably distinguish between a high-speed collision on a soft obstacle and a low-speed collision on a hard obstacle.

  According to claim 1 of the present invention, the above-mentioned problem with respect to the vehicle collision evaluation method is the vehicle collision evaluation method, wherein the vehicle has an acceleration sensor system and a pressure hose sensor. Using the pressure hose signal, which represents the signal of the pressure hose sensor, to determine a collision time point for a collision between the collision object and the vehicle, and using the collision time point to normalize the acceleration signal of the acceleration sensor system. And the acceleration signal represents the acceleration recorded by the acceleration sensor system, and the method further comprises the step of evaluating the normalized acceleration signal to obtain a collision estimate for the collision. Resolved, this collision evaluation allows the distinction between triggered and non-triggered situations.

  Advantageous embodiments result from the respective dependent claims and the following description.

1 is a schematic diagram of a crash assessment system having a vehicle airbag control system, according to one embodiment of the invention. 3 is a flowchart of a vehicle collision evaluation method according to an embodiment of the present invention. 6 is a graph having an acceleration signal when a vehicle collides with a collision object according to an embodiment of the present invention. 6 is another graph having an acceleration signal when a vehicle collides with a collision object according to an embodiment of the present invention. 5 is yet another graph with acceleration signals as a vehicle impacts an impact object, in accordance with an embodiment of the present invention. 5 is yet another graph with acceleration signals as a vehicle impacts an impact object, in accordance with an embodiment of the present invention. 5 is yet another graph with acceleration signals as a vehicle impacts an impact object, in accordance with an embodiment of the present invention. 5 is yet another graph with acceleration signals as a vehicle impacts an impact object, in accordance with an embodiment of the present invention.

  The determination of the triggered or non-triggered situation when the vehicle collides with the collision object can be better and easier if the collision time is known. If the time of this collision is known, the collision evaluation will be easy. However, from the above-mentioned signal of the airbag sensor system, the time of the above-mentioned collision cannot be determined partially or only with a delay. Combining the signals of the airbag sensor system with the signals of the pressure hose mounted well in front of the vehicle can contribute to a significant improvement in assessing the trigger situation.

  A well-known pressure hose or pressure hose sensor (PTS Pressure Tube Sensor) can be used in the approach described here. This pressure hose is provided, for example, between a bumper cross member and a foam arranged in front of it, is filled with air, and its end is closed by one pressure sensor at a time. For example, a collision with a pedestrian is identified by the deformation of the pressure hose and detected as a pressure signal by the pressure sensor. Another type of collision, for example with another vehicle or object, can also be detected by the pressure hose.

A vehicle crash evaluation method having an acceleration sensor system and a pressure hose sensor includes the following steps. That is,
Using the pressure hose signal representing the signal of the pressure hose sensor to determine a collision time point for a collision between a collision object and a vehicle;
Normalizing the acceleration signal of the acceleration sensor system using the point of collision, the acceleration signal representing a signal of acceleration recorded by the acceleration sensor system,
The above method further
There is the step of evaluating the normalized acceleration signal in order to obtain a collision estimate for the collision mentioned above, which collision evaluation makes it possible to distinguish between a triggered situation and a non-trigger situation.

  Crash assessment can be used to improve triggering of personnel protection systems in vehicles. The collision assessment can then evaluate the collision of the vehicle with the collision object, which may be another vehicle, a stationary stationary object, a hard obstacle, a soft barrier and/or an obstacle. It can be an object, a bicyclist and/or a pedestrian. This collision may occur on the front surface, and a part of the front surface of the vehicle and/or the entire front surface of the vehicle may overlap the collision target. The vehicles described above can be, for example, passenger cars and/or transport vehicles. The time of collision may be the time when the vehicle as described above collides with the collision object and/or the vehicle contacts the collision object. The above vehicle may have an airbag control device. The airbag control device can be arranged in the center tunnel of the vehicle and can be used for identifying a vehicle accident. An airbag sensor system can be arranged in the airbag control device. The airbag sensor system can be arranged in the vehicle separately from the airbag control device. The airbag sensor system described above may include an acceleration sensor system. The acceleration sensor system may include at least one acceleration sensor configured to record the acceleration of the vehicle in the driving direction. This running direction can also be referred to as the x-direction and/or the x-axis. The above acceleration can be represented by an acceleration signal. The acceleration sensor system described above can also be realized independently of the airbag sensor system. A pressure hose sensor can be used to identify pedestrian collisions. The pressure hose sensor can be attached to the bumper of the vehicle. The pressure hose sensor may be a pressure hose with one pressure sensor on each end. This deformation of the pressure hose due to the collision of the collision object can be identified as a pressure change of at least one pressure sensor of the pressure hose and can be output as a pressure hose signal. There may be crashes or collisions that may trigger personnel protection and/or trigger this. Such a situation can be called a trigger situation. A non-trigger situation can be understood as a situation in a collision or crash that does not and/or should not trigger personnel protection. A non-trigger situation can occur in a so-called 16km/h AZT guaranteed collision (Versicherungscrash). This can be referred to as a non-trigger situation, as triggering of personnel protection is not desirable during a collision with a stiff barrier at low speeds.

  It is also understood that the above-mentioned normalization of the acceleration signal using the collision time point means plotting (that is, evaluating) the acceleration signal to be normalized for the elapsed time counter started at the detected collision time point in the present invention. It is possible.

  In one embodiment, the step of evaluating evaluates the normalized acceleration signal using a predetermined threshold curve. When the acceleration signal is represented with reference to the time base obtained by the pressure hose sensor or the pressure hose signal, the normalized acceleration may be a time-dependent threshold curve in the case of a collision involving a trigger situation. It may exceed a defined threshold curve. In case of a collision with a non-trigger situation, the normalized acceleration signal does not reach the predetermined threshold curve.

  In the present invention, the time base can be understood to mean that the elapsed time counter starts operating after a predetermined time point. The duration or advance of the crash mentioned above is detected thereby. Critical to the start of this elapsed time counter is the effective sensor signal. The time base determined by the acceleration sensor is started, for example, as soon as the measured acceleration or the acceleration change exceeds a predetermined threshold value. The time base defined by the pressure sensor or pressure hose sensor is started, for example, as soon as the measured pressure or pressure change exceeds a predetermined threshold value.

  It is also advantageous if, in the step of evaluation, the normalized acceleration signal is evaluated using the duration from the time of the crash until the normalized acceleration signal exceeds a predetermined threshold value. This predetermined threshold can also be referred to as a reference threshold. If the duration is short, or if it falls below a predetermined boundary value, this is a fast trigger collision or trigger situation. If the above duration is long or if it exceeds a predetermined boundary value, this is a slow non-trigger collision or non-trigger situation. The above-mentioned predetermined threshold value or a force level depending on it in proportion thereto is selected, and this value is associated with the deformable member in the shock absorbing portion of the vehicle so that the above-mentioned collision speed is obtained within the collision type. It is possible to The crash velocity may be proportional to the duration of time from the crash time until the normalized acceleration signal exceeds a predetermined threshold. As the collision time point, the collision time point obtained by using the pressure hose signal can be used.

  In one embodiment of the invention, in the step of evaluating, the normalized acceleration signal is evaluated using the time from the point of collision to the characteristic signal course of the normalized acceleration signal. .. This characteristic signal course can be a characteristic acceleration peak, a temporary acceleration peak and/or an acceleration peak value in the acceleration signal. The characteristic signal course can correspond to the plastic deformation of the corresponding shock absorber member, which is characterized by a fixed, predetermined deformation displacement when a collision type is provided. You can The characteristic signal course should be detected, for example, when the acceleration value or the acceleration value representing the acceleration exceeds a predetermined minimum acceleration level and decreases again to a predetermined ratio of the maximum value reached by the above acceleration value. You can In one embodiment, the acceleration value may be reduced to 75% of the maximum value of this acceleration value, since the acceleration peak is characterized as a characteristic signal course. If the time from the point of collision to the characteristic signal elapses is short or below a predetermined boundary value, this can be a fast trigger collision or a trigger situation. If the time from the point of collision to the characteristic signal elapses above or exceeds a predetermined boundary value, this is a slow non-trigger collision or non-trigger situation. Due to the constant deformation displacement, the impact velocity can be inversely proportional to the measured time.

  According to yet another embodiment, the normalized acceleration signal may be used as part of the collision evaluation in the evaluation step to determine a collision type for the collision. The advantage obtained thereby is that at least one trigger threshold of the above trigger algorithm can be adapted depending on the determined collision type.

  In one embodiment, it is also advantageous to use the above collision evaluation in the step of adapting the threshold of the airbag algorithm and/or modifying the feature query of the airbag algorithm to adapt the threshold. Using the collision evaluation described above, in particular the collision type, the triggering algorithm described above can be adapted to the (current) collision type. In a "soft" crash, it is possible to adapt, i.e. reduce, the threshold value for triggering personnel protection measures to a correspondingly lower signal level of the acceleration signal.

  According to the invention, a vehicle crash evaluation device is constructed in such a way that the steps of the method according to the invention are carried out or realized by corresponding units. This embodiment variant of the invention in the form of a device makes it possible to solve the problem underlying the invention in a fast and efficient manner. The above-described vehicle collision evaluation device can be part of an airbag control device. This vehicle collision evaluation device can be implemented separately from the airbag control device. The device can be configured to read the pressure hose signal of the pressure hose sensor. The device can be configured to read the acceleration signal of the airbag sensor.

  In the context of the present invention, a device can be an electrical device that processes sensor signals and, depending on this, outputs control signals and/or data signals. The device may have an interface that may be configured with hardware and/or software. In a hardware configuration, the interface may be part of, for example, a so-called system ASIC that includes the different functions of the device. However, it is also possible that the interface described above is a unique integrated circuit or is composed at least partly of discrete components. In a software configuration, the above interface can be a software module, which is provided on the microcontroller in addition to another software module.

The vehicle collision evaluation system has the following features. That is,
A pressure hose sensor configured to record a collision time when the vehicle collides with a collision object, and to supply a pressure hose signal representing the collision time;
An acceleration sensor system configured to record acceleration and provide an acceleration signal representative of this acceleration;
It has a vehicle collision evaluation device.

  The crash assessment system described above can be part of an airbag system and/or a personnel protection system. The embodiment as a crash evaluation system is particularly advantageous. This is because all the required signals are detected here. It is also possible to combine and/or combine the crash assessment system and the airbag system.

  A computer program product having the following program code is also advantageous. That is, the program code can be stored on a machine-readable medium, such as semiconductor memory, fixed disk storage or optical storage, and if the program code executes on a computer or device. It is used to carry out the method described in one of the embodiments described above.

  One of the aspects of the present invention is to use a pressure hose sensor to detect the start time and the speed of a vehicle collision. Another aspect of the invention is to use the pressure hose sensor originally provided to detect a pedestrian accident as a "contact switch" to identify the beginning of a vehicle collision and use this information in an airbag trigger. It is to be used in the algorithm. To date, this information has only been required with very low accuracy when based on acceleration signals measured in airbag control systems. This severely limits the separation performance of the algorithm. An advantage of the present invention is that the pressure hose as a "contact switch" can provide the airbag trigger algorithm with extremely reliable information about crash initiation. If it is combined with the acceleration measured in the center tunnel, the crash speed can be obtained much more accurately. This allows for faster and more reliable distinction between triggered and non-triggered situations. This improves the trigger performance during high speed crashes and reduces the number of error triggers during low speed non-firing situations.

  Hereinafter, the present invention will be described in detail by way of example with reference to the accompanying drawings. In the following description of the preferred embodiment of the present invention, the same or similar reference numbers will be used for elements shown in different figures and operating in a similar manner. The repeated description of these members is omitted.

  FIG. 1 is a schematic diagram of a collision evaluation system having a vehicle airbag control device according to an embodiment of the present invention. The vehicle 100 has an airbag control device 110, which includes an acceleration sensor system 120 in the form of an airbag sensor system, which is connected to at least one personnel protection means 130. ing. Acceleration sensor system 120 is configured to detect the acceleration of vehicle 100 and provide a corresponding acceleration signal. The personnel protection means 130 can be, for example, an airbag and/or a seat belt tensioner in one embodiment. The airbag control device 110 is connected to the pressure hose sensor 140. The pressure hose sensor 140 is configured to output a pressure hose signal 145 representing the signal of the pressure hose sensor 140. The pressure hose sensor 140 is arranged in front of the front side of the vehicle between the bumper cross member and the foam arranged in front of the bumper cross member in the traveling direction 150.

  In another example, as shown in FIG. 1, the vehicle 100 may optionally include at least one upfront sensor 160 and at least one predictive sensor system 170.

  There is a collision object 180 in front of the vehicle 100 when viewed in the traveling direction 150, and this collision object collides with the collision object 180 or crashes the vehicle 100 onto the collision object 180 when the vehicle 100 goes straight ahead. Located in the immediate vicinity, in the illustrated scenario, an approximately 40 percent overlap between the vehicle front and the collision object 180 occurs. Further, the airbag control device 110 includes a collision evaluation device 190 for the vehicle 100.

  The crash assessment device 190 is configured to assess the crash of the vehicle 100, for example, with the crash target 180 using the pressure hose signal 145 and the acceleration signal. For example, the apparatus 190 described above may be configured to perform the steps of a crash assessment method for crash assessment as described with reference to FIG. To this end, the device 190 includes, in one embodiment, a calculating device that uses the pressure hose signal 145 to determine the point of impact, a normalizer that normalizes the acceleration signal using the point of impact, and the normalizer. And an evaluation device that evaluates the acceleration, which is used to perform collision evaluation for a collision. This collision evaluation includes a distinction between a trigger situation that triggers the vehicle personnel protection means 130 and a non-triggered situation that does not trigger the vehicle personnel protection means 130.

  FIG. 2 shows a flow chart of a vehicle collision assessment method according to one embodiment of the present invention. The vehicle collision evaluation method 200 includes a calculation step 210, a normalization step 220, and an evaluation step 230. The crash assessment method 200 may be performed on the crash assessment system 190 in the vehicle 100 shown in FIG. 1, in one embodiment.

  In step 210 of the calculation, the pressure hose signal 145 is used to determine when the vehicle 100 collides with the collision object 180. Here, the pressure hose signal 145 represents the signal of the pressure hose sensor 140. In a normalization step 220, this point of collision is used to normalize the acceleration signal of the acceleration sensor system described above, which results in a normalized acceleration signal. The acceleration signal represents the acceleration signal recorded by the acceleration sensor system. In an evaluation step 230, the normalized acceleration signal is evaluated to obtain a crash rating for the crash. Here, this collision evaluation includes distinction between a triggered situation and a non-triggered situation.

  FIG. 3 shows a graph of acceleration signals over time when a vehicle collides with a collision object according to one embodiment of the present invention. This acceleration signal can be recorded by the airbag sensor system shown in FIG. The time t is shown on the abscissa of the Cartesian coordinate system, and the acceleration Acc is shown on the ordinate. In this Cartesian coordinate system there are shown two acceleration signals 310, 315 representing the acceleration course recorded by the airbag sensor system after the vehicle has collided with the collision object. The origin of the abscissa is located at the absolute time when the vehicle collides with the collision object. The acceleration signal 310 represents a situation where the vehicle collides with the collision target at 64 km/h, in which case the collision target is a soft barrier. This is also referred to as 64 km/h ODB, and ODB stands for "Offset Deformable Barrier". The acceleration signal 315 represents that the vehicle collides with the collision object at 16 km/h, which is in this case a hard barrier. The collision recorded by the acceleration signal 315 is also referred to as 16 km/h AZT guaranteed collision (Versicherungscrash), AZT stands for Allianz Zentrum fuer Technologie, and AZT guaranteed collision is a test defined by AZT. That is. Here, the collision start 320 is obtained from the acceleration signal only after the acceleration threshold 330 or the start threshold 330 is exceeded due to signal noise. Collision initiation 322 can also be referred to as an algorithm timebase 320, which is associated with the standard algorithm of airbag control. The graph of FIG. 3 further shows the collision times 340 for the two acceleration signals 310, 315 determined by the pressure hose.

  FIG. 3 shows the acceleration-time course of a fast non-triggered crash on a hard barrier (16 km/h AZT guaranteed crash) versus a fast triggered crash on a soft barrier. The so-called absolute time, ie the time since the barrier contact, has been chosen as the time base. In the case of a slow crash, the deformation of the bumper foam and the other components that can exert only a slight reaction force lasts considerably longer than in the case of a fast trigger crash. Following this, in the case of a non-triggered crash, the crash box with the high force level deforms. On the other hand, in the above soft crash, the crash box deformation stops in the elastic region. This is because this relatively soft barrier deforms above a certain force level. The most serious problem with conventional airbag algorithms is that slow deformations of soft members (such as bumper foam) are not detected or only poorly detected during non-triggered crashes. This is because the acceleration generated at this time changes within the region of full braking (1g) or within the region of sensor noise below EMV. The algorithm-timebase can therefore only be defined above the so-called start threshold 330, such a start condition can be represented, for example, by a minimum threshold for the acceleration signal or a feature derived therefrom. This graph is based on "absolute time" (time since barrier contact or contact with a collision object) for fast triggered crashes (310) for soft barriers and slow non-triggered crashes (315) for hard barriers. Acceleration-shows the passage of time. The hypothetical algorithm-start threshold as well as the start time of each of these two crashes is shown as acceleration threshold 330. A possible detection of a crash initiation by the pressure hose above is marked as a collision time point 340.

  In FIG. 4, according to one embodiment of the present invention, an acceleration signal when a vehicle collides with a collision object is shown graphically over time. The origin of the horizontal axis is located at the collision start 320 when the vehicle collides with the collision target. That is, the acceleration signals 310, 315 start at this origin as soon as they exceed the acceleration threshold 330 or the start threshold 330. In other words, this time axis represents the time base as used in conventional airbag algorithms. The acceleration signals 310 and 315 correspond to the acceleration signals 310 and 315 shown in FIG.

  In FIG. 4, the acceleration signals 310, 315 are shown with reference to an algorithm time base that is initiated by exceeding a start threshold 330. Non-triggered crashes in this feature space have larger acceleration values in the relevant time domain than triggered crashes, which makes it difficult to correctly separate collision types (crashes). The diagram shown in FIG. 4 shows the acceleration-time course of a fast non-triggered crash (315) for a hard barrier versus a fast triggered crash (310) for a soft barrier based on the conventional algorithm-timebase. It is shown.

  FIG. 5 graphically illustrates a normalized acceleration signal over time as a vehicle impacts an impact object, in accordance with one embodiment of the present invention. The origin of the horizontal axis is located at the collision time point 340 when the vehicle collides with the collision object. That is, the normalized acceleration signals 510, 515 start at this origin as soon as the vehicle's pressure hose sensor identifies a collision. In other words, this time axis represents the time base that can be set using the pressure hose sensor or the pressure hose signal. These normalized acceleration signals 510, 515, which correspond to the acceleration signals 310, 315 already shown in FIG. 3, are shown after the start of the pressure hose base time base. In the graph of FIG. 5, a threshold curve 520 and a threshold 530 are further written. The normalized acceleration signal 510 for a fast crash on a soft barrier is above the threshold curve 520, while the acceleration signal 515 for a slow crash on a hard barrier always remains below the threshold curve 520. The normalized acceleration signals 510, 515 above exceed the threshold value 530 after a time 540 has elapsed after the collision point 340.

  However, a pressure hose in the bumper can be used to determine another time base. Since the pressure hose is located just behind the bumper foam and just before the bumper crossmember, it is compressed by pushing the bumper foam backwards after the start of the crash. This results in a significant increase in pressure at one or both of the two pressure sensors at each end of the pressure hose. This increase defines another time base for the pressure hose signal or "PTS contact signal" and the crash algorithm. In a rough approximation, the time point of the PTS contact signal is inversely proportional to the crash velocity, but is always earlier than the starting point of the acceleration-based algorithm. This is marked by the reference numeral 340 in FIG. 3 for the two crashes with 64 km/h or 16 km/h. In FIG. 5, normalized acceleration signals 510 and 515 are shown with respect to the time base detected by the pressure hose. By having the start time 340 earlier, the fully "absolute" time base of Figure 3 is largely retained, yet the two crashes can be clearly distinguished. FIG. 5 shows an example definition of a time-dependent threshold curve 520 that exceeds the triggered crash (510) but not the non-triggered crash (515). Such a threshold curve 520 is shown by a dotted line in FIG. Alternatively or simultaneously, the duration until the above-described normalized acceleration signals 510, 515 or features derived therefrom (filtered signal, integrated signal, etc.) reach a fixed threshold value 530 indicated by the dashed line in FIG. 540 is measured. If the duration 540 is short or below the threshold, this is a fast trigger crash. If the above duration is long or above the boundary value, this is a slow non-triggered crash. When the reference threshold value 530 is set so that the force level can be associated with the deformable member in the shock absorbing portion, for example, the bumper cross member is extended straight or the crash box fixing portion is flattened. It is even possible to directly estimate the crash velocity v0 within the same crash type/collision type above, if it is to be matched exactly to the pressing. In this case, this is inversely proportional to the duration 540 (or time 540) between the PTS contact signal 340 and above the reference threshold. As a further alternative, the duration can be measured until a characteristic signal course or a predetermined acceleration peak is produced in the normalized acceleration signals 510, 515 (possibly preprocessed). The acceleration peak corresponds to the plastic deformation of a given shock absorber member characterized by a fixed deformation displacement s in a given crash/crash type. For example, the acceleration peak should be above a predetermined minimum acceleration level, and the acceleration should drop to a predetermined percentage of the maximum acceleration reached, for example to 75% of the maximum reached. Can be easily detected. Alternatively, another peak identification method can be used. If the above duration is short or below the threshold, this is a fast triggered crash, and if the above duration is above or above the threshold, it is a slow non-triggered crash. Also in the case of this alternative method, the crash velocity v0 is inversely proportional to the measured time t, that is, v_0=constant/t, because the deformation displacement s is constant.

  In other words, FIG. 5 shows the acceleration time course of a fast triggered crash (310) for a soft barrier and a slow non-triggered crash (315) for a hard barrier based on the timebase derived by the pressure hose. There is. The detection of the trigger crash (510) can be performed, for example, by exceeding a time-dependent threshold, ie, the threshold curve 520, or by measuring the duration 540 until the reference threshold 530 is exceeded.

  FIG. 6 illustrates the accelerations of a vehicle impacting an impact object at different impact velocities over multiple cycles, in accordance with one embodiment of the present invention. The vertical axis shows the acceleration Acc and the horizontal axis shows the algorithm time in a plurality of cycles, where one cycle corresponds to a time of 0.5 ms. The origin of the horizontal axis is located at the collision start 320 when the vehicle collides with the collision target. That is, as soon as the acceleration threshold value 330 or the start threshold value 330 is exceeded at the collision start 320, the acceleration signals 610, 615, 620 start at the above-mentioned origin. Therefore, the above time axis represents the time base as used in conventional airbag algorithms. Shown here is the acceleration time course over multiple cycles (1 cycle=0.5 ms) of "algo time" when crashing into a hard obstacle at different speeds. The acceleration signal designated by reference numeral 610 is a collision at 56 km/h, the acceleration signal designated by reference numeral 615 is a collision at 40 km/h, and the acceleration signal designated by reference numeral 620 is a collision signal at 26 km/h. Represents a collision. All three acceleration signals 610, 615, 620 indicate that the vehicle will collide at a given velocity with complete overlap with a hard collision object. It is difficult to distinguish these different collision velocities from each other.

  6 and 7 again show the approach described in FIG. 5 for different fast crashes of the same crash type (completely overlapping a hard obstacle). In FIG. 6, the acceleration signal according to the conventional algorithm-timebase (above the threshold of the central acceleration sensor system) is plotted, where the different crash rates cannot be separated well.

  FIG. 7 is a graph showing accelerations in absolute time when a vehicle collides with a collision object at different collision speeds according to an embodiment of the present invention. The vertical axis represents the acceleration Acc. The origin of the horizontal axis is located at the absolute time when the vehicle collides with the collision target. This graph shows the acceleration time course in collisions/crashes on a hard obstacle at different speeds in ms for "absolute time". These graphs are referred to herein as normalized acceleration signals 710, 715, 720, since in this graph approximately the "PTS timebase", ie, a very similar figure to the above-mentioned normalized acceleration signal, is obtained. .. The normalized acceleration signal 710 corresponds to the acceleration signal 610 shown in FIG. 6, and correspondingly the acceleration signals 715 and 720 and the acceleration signals 615 and 620 are paired. Further shown in FIG. 7 is time 540. The dashed time 540 located below the time axis corresponds to the method according to the reference threshold described in FIG. 5, and the time 540 located above the time axis and shown as a solid line is the characteristic acceleration peak. Corresponds to the time 540 until the occurrence of The time 540 can have a value in the range of a few milliseconds. For example, the dashed time 540 may represent the values 6.5 ms, 9 ms and 12.5 ms.

  In other words, the acceleration signal is plotted in absolute time in FIG. Due to the extremely short time it takes for the pressure hose signal (PTS contact signal) to respond, one can start with a very similar diagram to the above plot of the pressure hose time base (PTS time base). In one embodiment, the time taken to exceed a fixed threshold indicated by the dashed line is measured. The corresponding times for different crashes are likewise indicated by dashed lines. In another embodiment, the time to identify the complete first acceleration peak is measured. The corresponding time is indicated by the solid arrow. In two examples, these times are shown to be clearly speed dependent.

  The trigger crash detection thus obtained can be used directly or indirectly to drive and control the restraint. Indirect drive control reduces the above threshold in existing trigger algorithms, for example, when a trigger crash is identified by an evaluation of the pressure hose time base. Alternatively, it is also possible to switch the main algorithm to another feature query if the detection by the above pressure horse timebase is successful (path concept). In addition to direct drive control of ignition means such as seat belt tensioners and airbags, the method described above is for controlling the fitness of restraint means, ie, belt tension limiter, secondary air bag. It can be used particularly advantageously to activate an adaptive valve opening in a bag stage or an airbag.

  The embodiments described above and shown in the drawings are selected for illustration only. The different embodiments can be combined with one another either completely or for individual features. It is also possible to supplement one embodiment with a plurality of characteristic configurations of another embodiment. Furthermore, the method steps according to the invention can be performed repeatedly as well as in a different order than described above. Where the example has a configuration "and/or" tied between the first and second characteristic configurations, this means that in one embodiment It should be understood that it has both the first characteristic configuration and the second characteristic configuration, and in another embodiment has only the first characteristic configuration or only the second characteristic configuration. is there.

  100 vehicle, 110 airbag control device, 120 acceleration sensor system, 130 personnel protection means, 140 pressure hose sensor, 145 pressure hose signal, 150 traveling direction, 160 up front sensor, 170 predictive sensor system, 180 collision object, 190 Collision evaluation device, 200 Collision evaluation method for vehicle, 210 Calculation step, 220 Normalization step, 230 Evaluation step, 310 Acceleration signal of fast trigger crash for soft barrier, 315 Acceleration signal of slow non-trigger crash for hard barrier, 320 Collision start, 330 acceleration threshold, 340 collision time point, 510,515 normalized acceleration signal, 520 threshold curve, 530 threshold value, 540 hours, 610,615,620 acceleration signal, 710,715,720 normalized acceleration signal, v0 crash speed

Claims (7)

In the collision evaluation method (200) for a vehicle (100),
The vehicle (100) has an acceleration sensor system (120) and a pressure hose sensor (140),
The method (200) comprises
Determining (210) a collision time point (340) for a collision between the collision object (180) and the vehicle (100) using the pressure hose signal (145) representing the signal of the pressure hose sensor (140);
Based on the acceleration signal (310, 315; 610, 615, 620) of the acceleration sensor system (120), the pressure hose time base acceleration signal (510, 510) with the collision time point (340) as the origin of the time coordinate (t). 515; 710, 715, 720) and the acceleration signal (310, 315; 610, 615, 620) of the acceleration recorded by the acceleration sensor system (120). Represents a signal,
The method further comprises
The method comprises a step (230) of evaluating the pressure hose time base acceleration signal (510, 515; 710, 715, 720) to obtain a collision rating for the collision, the collision evaluation leading to a soft obstacle. A trigger situation in which the personnel protection means (130) is triggered during a high-speed collision of the vehicle and a non-trigger situation in which the personnel protection means (130) is not triggered during a low-speed collision with a hard obstacle. Was
In the evaluation step (230), the time from the collision time point (340) until the pressure horse time base acceleration signal (510, 515; 710, 715, 720) exceeds a predetermined fixed threshold value (530). (540) is used to evaluate the pressure hose timebase acceleration signal (510, 515; 710, 715, 720),
A method (200). The method (200) of claim 1, wherein:
Evaluating said pressure hose timebase acceleration signal (510, 515; 710, 715, 720) using a predetermined threshold curve (520) in said evaluating step (230),
The pressure hose time base acceleration signal (510, 515; 710, 715, 720) exceeds the threshold curve (520) in the case of a collision with the trigger condition, and in the case of a collision with the non-trigger condition. Always remains below the threshold curve (520),
A method (200). The method (200) according to claim 1 or 2, wherein
In the evaluation step (230), the time (540) from the collision time (340) to a predetermined acceleration peak of the pressure horse time base acceleration signal (310, 315; 610, 615, 620) is used. , Evaluating the pressure hose time base acceleration signal (510, 515; 710, 715, 720),
A method (200). The method (200) of claim 3, wherein
The acceleration peak corresponds to the plastic deformation of the shock absorber member of the vehicle (100), which is characterized by a fixed predetermined deformation displacement (s) in a collision with the trigger situation or the non-trigger situation. ,
A method (200). In the collision evaluation device (190) for the vehicle (100),
The collision evaluation device (190)
Use pressure hoses signal (145) representative of the signal-flop train hose sensor (140), means for determining a collision point (340) for collision of the collision object and the (180) and the vehicle (100),
Acceleration signal of the acceleration sensor system representing the signal of the acceleration recorded by acceleration sensor system (120) (120); based on (310,315 610,615,620), the collision point (340) time coordinate ( means for generating a pressure hose time base acceleration signal (510, 515; 710, 715, 720) which is the origin of t);
Means for evaluating the pressure hose time base acceleration signal (510, 515; 710, 715, 720) to obtain a crash rating for the crash;
Have
According to the collision evaluation, the trigger situation in which the personnel protection means (130) is triggered during a high-speed collision with a soft obstacle, and the personnel protection means (130) during a low-speed collision with a hard obstacle. Is distinguished from non-triggered situations where
The evaluating means includes a time (540) from the collision time (340) until the pressure horse time base acceleration signal (510, 515; 710, 715, 720) exceeds a predetermined fixed threshold value (530). To evaluate the pressure hose time base acceleration signal (510, 515; 710, 715, 720) using
A collision evaluation device (190) characterized by the above. In a collision evaluation system for a vehicle (100),
The collision assessment system has the following features:
A pressure hose configured to record a collision time (340) at which the vehicle (100) collides with a collision object (180) and to supply a pressure hose signal (145) representative of the collision time (340). A sensor (140),
An acceleration sensor system (120) configured to record acceleration of the vehicle (100) and provide acceleration signals (310, 315; 610, 615, 620) representative of the acceleration.
It has the collision evaluation device (190) for vehicles (100) described in Claim 5, Comprising:
A collision evaluation system for a vehicle (100).   A computer program having a program code for causing a method (200) according to any one of claims 1 to 4 to be executed on an apparatus (190) according to claim 5.

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