Vehicle collision safety redundancy design method

Abstract

The invention provides a vehicle collision safety redundancy design method. The vehicle collision safety redundancy design method comprises the steps of extracting a simulation acceleration a21 of an ACU position in a target vehicle model analogue simulation model from a whole vehicle simulation analysis model; selecting a reference vehicle model which is highly similar to the target vehicle model and has calibration data, extracting acceleration of a plurality of existing real vehicle collision data ACU positions, finding out the acceleration closest to a21, and naming the acceleration as a31; a21 and a31 are compared, if a31 is smaller than or equal to a21, a31 serves as a calibration acceleration, otherwise, a31 is scaled to a21 to serve as the calibration acceleration, and ACU program calibration is carried out; and determining a theoretical collision moment, and selecting a moment for sending a dangerous source cut-off signal according to the theoretical collision moment. According to the method, a dangerous source disconnection function is realized under the condition of no real vehicle collision data, and a method for realizing full functions of the ACU in the acquisition stage is provided, so that the safety redundancy of the system can be improved, and the safety of a driver and passengers is fully ensured.

Description

Technical Field

[0001] The present invention relates to the field of automobiles, and in particular to a vehicle collision safety redundancy design method. Background Art

[0002] The current automotive design field has increasingly higher requirements for testing efficiency and accuracy in the R&D stage. In the development of vehicle collision safety, for new platform models, the main method is to collect and verify relevant design performance through real vehicle testing. The first round of test collection mainly examined the structural design and the ACU collision-free ignition function, but it was not possible to verify the execution of the function of cutting off dangerous sources such as high voltage electricity through ACU in the first round of tests. Due to the single data collection method, there is only a second verification phase test for the dangerous source cutting function test, and the number of verifications is unique. If the requirements are not met, a separate sample car needs to be added for this function, resulting in a large amount of sample cars, time and repeated testing costs in the design process. Summary of the invention

[0003] In view of the defects in the prior art, the purpose of the present invention is to provide a vehicle collision safety redundant design method, which aims to integrate simulation data and existing collision vehicle model data, perform redundant design of the hazard source cut-off moment, and provide a redundant design test process.

[0004] To achieve the above-mentioned object of the invention, the present invention adopts the following technical solution, which includes the following steps:

[0005] S1 performs ACU acceleration parameter calibration;

[0006] S101, extracting the simulated acceleration a21 of the ACU position from the whole vehicle simulation analysis model;

[0007] S102, selecting a reference vehicle model with existing calibration data that is highly similar to the target vehicle model, extracting the accelerations of the ACU positions of several existing real vehicle collision data, and finding the acceleration closest to a21, which is named a31;

[0008] S103, compare a21 and a31, if a31≤a21, a31 is used as the calibration acceleration, otherwise a31 is scaled to a21 as the calibration acceleration, and the ACU program calibration of the corresponding working condition is performed;

[0009] S104, increasing the safety margin range of a31 by a first proportion %, obtaining acceleration a32, determining whether the minimum acceleration based on the a32 curve is not less than the working condition setting value, if so, ending the working condition calibration; if not, reducing the safety margin until the setting condition is reached;

[0010] S105: Calibration of other working conditions of the whole vehicle, refer to the above steps S101-S104, complete the calibration of other working conditions, and then complete the ACU calibration of the whole vehicle;

[0011] S2 performs calibration of redundant design when cutting off the danger source:

[0012] S201, determining the theoretical collision time: according to theoretical calculation, the ignition time of the airbag is t11, the ignition time of the pre-tensioned seat belt is t12, the time when the danger source is encountered in the collision condition is t21, and the required time length for executing the cutting off of the danger source is t22;

[0013] S202, taking the minimum value of t11 and t12 as the minimum ignition time t13, taking the minimum value of t13 and |t21-t22| as the time t23 for sending a collision signal to cut off the danger source, and the duration of t23 is determined according to the shortest time required by the program;

[0014] S203, using t23 to calibrate the ACU programs corresponding to different working conditions, and selecting different ACUs according to different working conditions required for the collision test.

[0015] Preferably, in step S1, if there is no actual vehicle test data as a reference, the ACU acceleration a21 in the whole vehicle simulation can be directly used as the calibration curve a31: and during verification, the original safety margin range of a31 is increased by a second proportion to obtain a32, and it is determined whether the minimum ignition acceleration of the a32 curve is not less than the operating condition setting value. If so, the calibration is terminated, otherwise the safety margin is reduced until the set condition is met.

[0016] Preferably, step S104 also includes limiting the range after reducing the safety margin to be no less than 1 times the original safety margin range; if the set condition cannot be achieved by adjusting the safety margin, modifying the calibration program so that the minimum acceleration limit of the calibrated acceleration of the corresponding working condition for sending a collision signal is no less than the working condition set value.

[0017] Preferably, the method further comprises the following steps:

[0018] S3 system test: The calibrated ACU is assembled and tested on a real vehicle. A simulated signal is used to test whether the ACU can normally execute the procedure of cutting off the hazard source after receiving the collision signal. The test is started and the sending time of the collision data and the related time of the actuator are recorded, and it is analyzed whether the redundant design goal is achieved.

[0019] Preferably, the S3 step also includes: preparing an ACU and a VCU with collision-specific functions, and assembling a test vehicle, using a simulated signal to test whether the ACU and the VCU can normally execute the program of cutting off the source of danger after receiving the collision signal, starting the test and recording the sending time of the collision data and the relevant time of the actuator, and analyzing whether it achieves the redundant design goal.

[0020] Preferably, the VCU calibration method with collision-specific function is:

[0021] S401, non-destructive vehicle test or obtaining the vehicle acceleration a41 under maximum braking force based on the reference vehicle model;

[0022] S402, reading the vehicle acceleration a51 of the vehicle collision under different working conditions from the vehicle simulation model;

[0023] S403, VCU identifies different collision acceleration directions and positive and negative values ​​according to different collision conditions; frontal collision mainly identifies X-direction acceleration, which is a negative value; left-side collision mainly identifies Y-direction acceleration value, which is a positive value; rear collision mainly identifies X-direction acceleration value, which is a positive value;

[0024] S404. According to |a51|≥|a61|≥1.2*|a41|, the acceleration a61 threshold value for the VCU to send a dangerous source cut-off signal is set, and the VCU under different working conditions is calibrated.

[0025] Preferably, the VCU with a collision-specific function includes adding a collision input signal control circuit at the front end of the VCU, and the VCU sends a danger source cut-off signal according to the collision signal.

[0026] Preferably, S3 system tests are also included:

[0027] S301, prepare the ACU and VCU with special collision functions and assemble them into a test vehicle;

[0028] S302, whether the detection function is normal, using a simulation signal to test whether the ACU and VCU can normally execute the program of cutting off the dangerous source after receiving the collision signal;

[0029] S303, sample vehicle transportation, adopting zero-kilometer transportation;

[0030] S304, laboratory preparation, first dismantle the actuators with ignition function of ACU and VCU, and restore the installation of the actuators after the test preparation is completed;

[0031] S305 , start testing and record the sending time of the collision data and the related time of the actuator, and analyze whether the redundant design goal is achieved.

[0032] Preferably, the lower limit value of step a61 in step S305 is set to a value between 1.0*|a41| and 1.3*|a41|.

[0033] Preferably, the first ratio and / or the second ratio is / are 10% or 20% or 30% or a ratio between 10-30%.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The present invention converts the simulated acceleration data of a new platform vehicle model into a calibrated acceleration alone or in combination with other vehicle model data, so that the danger source disconnection / alarm function can be realized without the need for real vehicle collision data;

[0036] 2. The present invention provides a method for integrating simulation data with existing collision vehicle model data, so that the calibration data is closer to actual needs and can meet safety requirements;

[0037] 3. The present invention provides a redundant design for the disconnection time of the dangerous source, provides the earliest theoretical time, and achieves the fastest power-off design, which can ensure the safety of subsequent passengers;

[0038] 4. The present invention provides a test process for collision safety redundant design, which can verify the disconnection of the hazard source for a second time, thereby improving verification redundancy and reducing test and design costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0040] Figure 1 Schematic diagram of the method for fusing test data and simulation data in the first embodiment;

[0041] Figure 2 This is the actual vehicle testing method flow after the redundancy design is completed in the first embodiment;

[0042] Figure 3 Schematic diagram of the external circuit controlling the VCU collision function in the second embodiment. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0045] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, all directional indications in this application (such as up, down, left, right, front, back, bottom...) are only used to explain the relative position relationship, movement, etc. between the components in a certain specific posture (as shown in the drawings). If the specific posture changes, the directional indication will also change accordingly.

[0046] First Embodiment

[0047] This embodiment provides a vehicle collision safety redundancy design method, which mainly includes the following steps:

[0048] S1: Calibrate ACU parameters by fusing test data and simulation data

[0049] like Figure 1 As shown, extract the ACU acceleration curves a11, a12, and a13 in the frontal rigid collision condition. Select the vehicle models c11, c12, and c13 from the existing real vehicle collision database (you can also select more or less vehicle model data). Extract the ACU acceleration curve a21 in the frontal collision simulation model. Find the acceleration curve closest to a21 from a11, a12, and a13, and name it a31. Compare the maximum eigenvalues ​​of the two. If a31≤a21, directly use a31 as the calibration acceleration. If a31>a21, scale a31 to a21 as the new a31 calibration acceleration curve.

[0050] Based on the a31 acceleration curve, calibrate according to the calibration-related procedures, and at the same time increase the safety margin range of a31 by 20% to 1.2 times the original safety margin (±50%), that is, (±60%), and the resulting curve is a32. Compare whether the minimum ignition acceleration of curve a32 is greater than or equal to the preset value of the frontal collision condition. In this embodiment, the minimum acceleration is greater than or equal to the preset value of the condition 5g, and the calibration of the condition is completed. Take other working conditions of the whole vehicle, follow the above data fusion steps, and take the minimum acceleration limit of each working condition to complete the calibration of other working conditions, and then complete the ACU calibration of the whole vehicle. In other embodiments, the increase value (first ratio) of the safety margin range of the verification process can also be 10% or 20% or 30% or a ratio between 10-30%, and the increased margin is calculated as an increase of the first ratio based on the original safety margin range.

[0051] In other side and rear collision conditions, the preset value is 5g, and in frontal, side and rear collisions, the preset value is 5g; under different conditions, the original safety margin range of A31 is ±50%, preferably -30% to +50%.

[0052] In other embodiments not shown, if the minimum ignition acceleration of a32 is less than 5g, the calibrated safety margin range of a32 is reduced (but the limit margin is not less than 1 times (±50%) of the original) until the minimum acceleration of a32 is greater than or equal to the working condition setting value of 5g. If the minimum acceleration is still not greater than 5g after the safety margin is reduced, the calibration program is modified so that the minimum acceleration limit of the calibrated acceleration of the working condition to send a collision signal is not less than 5g. The calibrated acceleration curve of the working condition is determined to be completed.

[0053] S2: Calibration of redundant design at the moment of cutting off the danger source

[0054] According to theoretical calculations, the ignition time of the airbag in the frontal collision condition is t11 = 18ms, and the ignition time of the pre-tensioned seat belt is t12 = 13ms. The analysis shows that the frontal collision speeds are 25 km / h, 50 km / h, and 56 km / h, the offset collision speed is 64 km / h, and the MPDB collision speed is 50 km / h. In the above frontal collision conditions, the minimum time of hitting the danger source is t21 = 40ms, and the time required to execute the cutting process is t22 = 100ms. The minimum value t13 between t11 and t12 is taken as the minimum ignition time of the airbag and seat belt. t11 is less than t12, so t13 = t11 = 13ms is taken. The minimum value between t13 and (t22-t21) is taken as the time t23 for sending the collision signal. Since t13 < (t22-t21), t23 = t13 = 13ms is taken. That is, the time for sending the collision signal to cut off the danger source is t23 = 13 ms.

[0055] S3: Real vehicle hazard source disconnection and alarm system test

[0056] like Figure 2 As shown, first prepare the ACU (with ignition function) and VCU (with ignition function) dedicated to the collision prototype to assemble the actual vehicle. Use simulation signals to test whether the ACU and VCU functions are normal, and can receive collision signals to reduce high voltage and cut off oil. Then transport the prototype vehicle through zero-kilometer transportation and prepare for the test. During the laboratory preparation work, disassemble the ACU, VCU and other actuators with ignition functions, and restore the ACU and VCU installation after the test preparation is completed. Add test equipment during the test to record the sending time of the collision data and the execution time of the actuator. Analyze the collected test data and achieve the early design goals.

[0057] In other embodiments, when assembling the test vehicle, only the ACU with the collision function and the VCU without the collision function may be used.

[0058] In this embodiment, the VCU has a collision function. The VCU uses an internal control program to control the BMS power off, other mechanisms to cut off fuel, and start the warning system. The relevant collision program calibration method is as follows:

[0059] S401, obtaining the vehicle acceleration a41 under the maximum braking force through non-destructive real vehicle testing; in other embodiments, existing reference vehicle model data with high similarity to the target vehicle model may be selected as the vehicle acceleration a41;

[0060] S402. Read the vehicle acceleration a51 of the vehicle collision under different working conditions from CAE simulation. At the same time, in a single collision condition, the acceleration direction of a51 is certain. For example, if the direction from the rear of the vehicle to the front of the vehicle is the positive X direction, the direction from the left side to the right side is the positive Y direction, and the direction from the bottom of the vehicle to the top of the vehicle is the positive Z direction, then in a frontal collision, the vehicle acceleration in the X direction must be negative; in the left barrier collision condition, the vehicle acceleration in the Y direction is positive; in the rear collision condition, the vehicle acceleration in the X direction is positive;

[0061] S403, VCU identifies different collision acceleration directions and positive and negative values ​​according to different collision conditions. For example, in a frontal collision, the X-direction acceleration is mainly identified, and it is a negative value; in a left collision, the Y-direction acceleration value is mainly identified, and it is a positive value; in a rear collision, the X-direction acceleration value is mainly identified, and it is a positive value.

[0062] S404, the acceleration a61 threshold value for VCU to send power-off, fuel-off and other signals is set. In order to ensure that the collision condition of the whole vehicle can be identified according to the acceleration of the whole vehicle during a collision, and to send power-off, fuel-off and other signals at the same time, the acceleration a61 threshold value is as small as possible. The positive and negative values ​​of a61 are set according to the setting of S403, and the size is set according to the method of |a51|≥|a61|≥1.2*|a41|, and the duration requirement is determined according to the shortest time required by the program. In other embodiments, the lower limit value of the value range of a61 can preferably be 1*|a41|, 1.3*|a41| or 1.4*|a41|, or any number between 1 and 1.4 times |a41|.

[0063] S405, calibrating the acceleration programs of different working conditions, determining the magnitude, direction, and duration of the acceleration a61, and writing them into the VCU programs of different working conditions.

[0064] S406. Under different collision conditions, select different VCUs to perform relevant collision tests.

[0065] Second Embodiment

[0066] The redundancy design method of this embodiment is substantially the same as that of the first embodiment. One difference is that another method is provided for the ACU parameter calibration in step S1:

[0067] In the absence of actual vehicle test data as a reference, the calibration steps can be shortened. The ACU value a21 in the target vehicle simulation model is directly used as the acceleration calibration curve a31. Based on the a31 curve, according to the calibration-related procedures, the safety margin is increased by a second ratio of 20%, to 1.2 times (±60%) of the original safety margin required by conventional technology, and the calibrated curve is a32. Comparing the minimum ignition acceleration of curve a32, if the minimum acceleration is greater than or equal to 5g, the calibration is completed. Otherwise, reduce the calibration safety margin of a32 (the safety margin is not less than 1 times the original (±50%)) until the minimum acceleration is greater than or equal to 5g. If the minimum acceleration is still not greater than 5g after the margin is reduced, modify the calibration procedure so that the minimum acceleration limit of the calibration acceleration of this working condition to send a collision signal is not less than 5g. The calibration acceleration curve of this working condition is determined to be completed. The calibration of other working conditions also refers to the above calibration steps, and the minimum acceleration limit of each working condition is taken to complete the calibration of other working conditions, and then the ACU calibration of the whole vehicle is completed.

[0068] In other embodiments, the second ratio may also be 10% or 30% or a ratio between 10-30%, and the increased safety margin is calculated as an increase of the second ratio based on the original safety margin range.

[0069] The difference between this embodiment and the first embodiment is that the implementation method of the VCU with collision function in this embodiment is: the VCU uses external line control to send power-off, fuel-off and other request signals. Figure 3 As shown, a special collision input signal control circuit is added to the front end of the VCU. The specific process is as follows:

[0070] S501, the signal of the external control circuit is sent by the specific device at the time of collision;

[0071] S502: After receiving the vehicle collision signal, the external control circuit provides a status signal to the VCU;

[0072] S503, the VCU determines that the actual vehicle has collided according to the status signal, and outputs power-off, fuel-off, and alarm signals;

[0073] S504, the BMS and other actuators execute the actions of the predetermined program to complete the relevant functions.

[0074] The above describes the specific embodiments of the present invention. Based on the above description, relevant personnel can make various changes and modifications without departing from the technical concept of the present invention.

Claims

1. A vehicle collision safety redundancy design method, characterized in that: The steps include: S1 performs ACU acceleration parameter calibration; S101, extracting the simulated acceleration a21 of the ACU position from the whole vehicle simulation analysis model; S102, selecting a reference vehicle model with existing calibration data that is highly similar to the target vehicle model, extracting the accelerations of the ACU positions of several existing real vehicle collision data, and finding the acceleration closest to a21, which is named a31; S103, compare a21 and a31, if a31≤a21, a31 is used as the calibration acceleration, otherwise a31 is scaled to a21 as the calibration acceleration, and the ACU program calibration of the corresponding working condition is performed; S104, increasing the safety margin range of a31 by a first ratio to obtain acceleration a32, and determining whether the minimum acceleration based on the a32 curve is not less than the working condition setting value, if so, ending the working condition calibration; if not, reducing the safety margin until the setting condition is reached; S105: Calibration of other working conditions of the whole vehicle, refer to the above steps S101-S104, complete the calibration of other working conditions, and then complete the ACU calibration of the whole vehicle; S2 performs calibration of redundant design when cutting off the danger source: S201, determining the theoretical collision time: according to theoretical calculation, the ignition time of the airbag is t11, the ignition time of the pre-tensioned seat belt is t12, the time when the danger source is encountered in the collision condition is t21, and the required time length for executing the cutting off of the danger source is t22; S202, taking the minimum value of t11 and t12 as the minimum ignition time t13, taking the minimum value of t13 and |t21-t22| as the time t23 for sending a collision signal to cut off the danger source, and the duration of t23 is determined according to the shortest time required by the program; S203, using t23 to calibrate the ACU programs corresponding to different working conditions, and selecting different ACUs according to different working conditions required for the collision test.

2. The vehicle collision safety redundancy design method according to claim 1, characterized in that: In step S1, there is no actual vehicle test data as a reference, and the ACU acceleration a21 in the whole vehicle simulation can be directly used as the calibration curve a31: and during verification, the original safety margin range of a31 is increased by the second ratio to obtain a32, and it is determined whether the minimum ignition acceleration of the a32 curve is not less than the operating condition setting value. If so, the calibration is terminated, otherwise the safety margin is reduced until the set conditions are met.

3. The vehicle collision safety redundancy design method according to claim 1 or 2, characterized in that: Step S104 also includes limiting the range after reducing the safety margin to be no less than 1 times the original safety margin range; if the set conditions cannot be met by adjusting the safety margin, modifying the calibration program so that the minimum acceleration limit of the calibrated acceleration of the corresponding working condition for sending a collision signal is no less than the working condition set value.

4. The vehicle collision safety redundancy design method according to claim 1, characterized in that: The following steps are also included: S3 system test: The calibrated ACU is assembled and tested on a real vehicle. A simulated signal is used to test whether the ACU can normally execute the procedure of cutting off the hazard source after receiving the collision signal. The test is started and the sending time of the collision data and the related time of the actuator are recorded, and it is analyzed whether the redundant design goal is achieved.

5. The vehicle collision safety redundancy design method according to claim 4, characterized in that: The S3 step also includes: preparing an ACU and a VCU with special collision functions, and assembling a test vehicle, using a simulated signal to test whether the ACU and the VCU can normally execute the program of cutting off the source of danger after receiving the collision signal, starting the test and recording the sending time of the collision data and the related time of the actuator, and analyzing whether it has achieved the redundant design goal.

6. The vehicle collision safety redundancy design method according to claim 5, characterized in that: The calibration method of VCU with collision-specific function is as follows: S401, non-destructive vehicle test or obtaining the vehicle acceleration a41 under maximum braking force based on the reference vehicle model; S402, reading the vehicle acceleration a51 of the vehicle collision under different working conditions from the vehicle simulation model; S403, VCU identifies different collision acceleration directions and positive and negative values ​​according to different collision conditions; frontal collision mainly identifies X-direction acceleration, which is a negative value; left-side collision mainly identifies Y-direction acceleration value, which is a positive value; rear collision mainly identifies X-direction acceleration value, which is a positive value; S404. According to |a51|≥|a61|≥1.2*|a41|, the acceleration a61 threshold value for the VCU to send a dangerous source cut-off signal is set, and the VCU under different working conditions is calibrated.

7. The vehicle collision safety redundancy design method according to claim 5, characterized in that: The VCU with a collision-specific function includes adding a collision input signal control circuit to the front end of the VCU, and the VCU sends a danger source cut-off signal according to the collision signal.

8. The vehicle collision safety redundancy design method according to claim 1, characterized in that: Also includes S3 system tests: S301, prepare the ACU and VCU with special collision functions and assemble them into a test vehicle; S302, whether the detection function is normal, using a simulation signal to test whether the ACU and VCU can normally execute the program of cutting off the dangerous source after receiving the collision signal; S303, sample vehicle transportation, adopting zero-kilometer transportation; S304, laboratory preparation, first dismantle the actuators with ignition function of ACU and VCU, and restore the installation of the actuators after the test preparation is completed; S305 , start testing and record the sending time of the collision data and the related time of the actuator, and analyze whether the redundant design goal is achieved.

9. The vehicle collision safety redundancy design method according to claim 5, characterized in that: The lower limit value of step a61 in step S305 is set to a value between 1.0*|a41| and 1.3*|a41|.

10. The vehicle collision safety redundancy design method according to claim 1 or 2, characterized in that: The first ratio and / or the second ratio is preferably 10% or 20% or 30% or a ratio between 10-30%.

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