A design and analysis method of pedestrian protection headform test

Abstract

This invention discloses a design and analysis method for pedestrian head impact testing, belonging to the field of automotive collision technology. Specifically, it includes the following steps: obtaining scores for all impact points of the pedestrian head impact through simulation analysis; selecting representative head impact points (one-third of the total number of impact points) and conducting tests and scoring of pedestrian head impact performance using either the grid point method or the equal region method. Specifically, the verification of pedestrian head impact performance is performed using either the grid point method or the equal region method. This method, by conducting pedestrian head impact simulation analysis during the engineering design phase, allows for early performance score evaluation and optimization, ensuring the passability of the pedestrian head impact performance score. It avoids the problem of significant deformation of the test vehicle structure after more than two hundred impact tests, which could lead to a decrease in the accuracy and reliability of later test results.

Description

Technical Field

[0001] This invention belongs to the field of automotive collision technology, specifically relating to a design and analysis method for pedestrian head protection tests. Background Technology

[0002] The scope of vehicle front-end collision tests involving pedestrian head impacts is gradually expanding, making the evaluation of pedestrian head protection performance quite challenging, mainly due to the following three factors:

[0003] First, pedestrian protection head shape performance is highly dependent on vehicle styling. This is mainly because the head shape testing area is tailored to the specific vehicle's styling characteristics. Using the same marking rules, the testing area varies from vehicle to vehicle, with no two testing areas being exactly alike. Currently, vehicles on the market have unique designs, with significant differences between models from different automakers. Different vehicle categories, such as A / B / C / C+ / D-class sedans, A / B / C-class SUVs, and MPVs, each have their own distinct styling. Even if automakers adopt a family-style design, variations in vehicle height and front-end dimensions mean that the head shape testing area, determined according to the pedestrian protection testing regulations of C-NCAP, will differ from other models. Therefore, styling is the primary factor influencing head shape performance evaluation.

[0004] Secondly, the different vehicle designs result in significant differences in vehicle structure, and the structures used by different car manufacturers and different models vary considerably. Therefore, vehicle structure is the second factor affecting head shape performance evaluation.

[0005] Third: The materials used by different car manufacturers, and the materials used by different car manufacturers in different levels of models, are different. Moreover, the different materials used, especially the materials used in non-metallic parts, are the third factor affecting the head shape performance evaluation.

[0006] Automakers generally employ two methods to assess pedestrian head impact performance. The first method involves testing all head impact points according to testing requirements and using the results to evaluate head impact performance. These results are then provided to the relevant testing department as predictions before the official C-NCAP tests. The disadvantages of this method are high cost, long cycle time, and significant structural deformation of the test vehicle after over two hundred head impact tests, leading to a decrease in the accuracy and reliability of later test results. The second method combines testing with simulation analysis for head impact performance evaluation. This method relies on high-precision pedestrian head impact simulation analysis results and a well-developed head impact testing verification plan to quickly and efficiently complete the pedestrian head impact performance evaluation. Summary of the Invention

[0007] To address the problems of high testing cycles and costs, and significant deformation of test vehicle structures after more than two hundred head impact tests leading to decreased accuracy and reliability of later test results, this invention provides a design and analysis method for pedestrian head impact tests. Based on the simulation analysis of injury values ​​at pedestrian head impact points, this method selects representative head impact points (one-third of the total number of head impact points) to formulate a test verification plan.

[0008] This invention is achieved through the following technical solution:

[0009] A method for designing and analyzing pedestrian head shape protection tests, specifically including the following steps:

[0010] Through pedestrian protection head shape simulation analysis, the scores of head shape performance at all impact points are obtained;

[0011] Representative head impact points, representing one-third of the total head impact points, were selected, and the performance of pedestrian head protection was tested and scored using either the grid point method or the equal area method.

[0012] Furthermore, the test verification of the pedestrian protection head shape performance is specifically carried out by conducting head shape tests and scoring according to the grid point method or the equal area method.

[0013] Furthermore, the selection of representative head-shaped impact points follows the specific selection rules as follows:

[0014] A1. Hairpiece central area damage chromatography (HIC) 15 Select one point with a value ≤ 600, and this point will not have secondary collisions with hard points inside the cabin;

[0015] A2. Glass area: Selected according to the energy absorption space of the head impact point;

[0016] A3. Wiper area: Select at least one head-shaped impact point near each wiper axis;

[0017] A4. Sink cover area: Select the point with the highest head impact damage value, the point with the lowest head impact damage value, and the point where the head damage value is close to the color jump threshold.

[0018] A5. Headlight area: Select a point where the head injury value is close to the critical value of the color jump in the color spectrum;

[0019] A6. Select a point where the head injury value is close to the critical value of the color jump in the color spectrum;

[0020] A7. Hard point structural areas in the cabin: Classified according to different hard point areas, the head shape points are evaluated according to the head shape injury curve of different zones, and each head shape point is given a corresponding evaluation score.

[0021] Furthermore, in A2, the energy-absorbing space in the glass region refers to the z-axis space dimension between the glass and the downward z-axis structure of the glass at the head impact point.

[0022] The energy absorption space in the glass area is segmented according to color zones: Red head color: energy absorption space ≤ 50mm; Brown head color: 50mm < energy absorption space ≤ 60mm; Orange head color: 60mm < energy absorption space ≤ 75mm; Yellow head color: 75mm < energy absorption space ≤ 90mm; Green head color: energy absorption space > 90mm.

[0023] For each chromatogram, a head-shaped impact point must be selected, and the point where the energy absorption space of each chromatogram is close to the critical point must be selected.

[0024] Furthermore, in A6, the lesion spectrum for head-shaped sites is green, HIC 15 Points with a value ≥600 are listed as options; the damage spectrum for head-shaped points is yellow, and 650 < HIC. 15 ≤700 and 950≤HIC 15 Points with a damage score ≤1000 are listed as options; the damage spectrum for head-shaped points is orange, and 1000 < HIC. 15 ≤1100 and 1250≤HIC 15 Points with a value ≤1350 are listed as options; the lesion spectrum for head-shaped points is brown, and 1350 < HIC. 15 ≤1450 and 1600≤HIC 15 Points with a damage rating of ≤1700 are listed as options; head-shaped points are indicated by a red damage spectrum, and 1700 < HIC. 15 Points with a resolution of ≤1800 are listed as options.

[0025] Furthermore, if the representative head impact points selected according to the above 7 criteria exceed 1 / 3 of the total number of head impact points, a comprehensive score will be calculated based on the scores of all points, and the points will be simplified after ranking.

[0026] Furthermore, the principles of simplification are as follows:

[0027] B1. Select points with poor damage values ​​within the symmetrical region;

[0028] B2. Prioritize retaining the lower critical value point and remove the upper critical value point.

[0029] Furthermore, the test and scoring of pedestrian head protection performance using the grid point method specifically includes the following:

[0030] A grid-point method was used for head shape testing and scoring. The prediction results were divided into grid points with specific prediction results, grid points with default prediction results, and grid points with unpredictable results. During the evaluation, for grid points with specific prediction results, 10 grid points were randomly selected according to the color distribution ratio for test verification. Finally, the sum of the score points obtained from the verification test points was divided by the sum of the score points of the corresponding prediction results to calculate the correction coefficient. The correction coefficient was used to correct the prediction results of all grid points with prediction results, and the corrected result was used as the score point for calculating the evaluation result. When the correction coefficient is between 0 and 1... When the correction factor is within the range of 8 to 1.2, it is considered acceptable; if the correction factor is greater than 1.2, the correction factor is 1.2; if the correction factor is less than 0.8, the correction factor is reduced by 0.2; for grid points with default prediction results, they are directly used as the score for calculating the evaluation result; for grid points with unpredictable results, grid points that cause significant harm to pedestrians are selected in each blue area for testing, and the corresponding score is obtained according to the C-NCAP management rules based on the HIC15 value of the test results, and multiplied by the number of grid points in that blue area as the score for calculating the evaluation result.

[0031] Furthermore, the test and scoring of pedestrian head protection performance using the equal-area method specifically includes the following:

[0032] According to the purchase plan for engine hood parts required to complete the test in full, the head shape test area is divided into 18 equal areas, each of which is further divided into 4 or 2 zones. One point within each equal area that may cause significant injury to pedestrians is selected for testing. Based on the test results and the judgment criteria according to C-NCAP management rules, a score is calculated for each test point, i.e., the score for the zone where the test point is located. This score can be used as the score for all zones within the equal area. For symmetrical equal areas, one side can be selected for testing and scoring. For equal areas where no test point is selected, the score for the symmetrical equal area is obtained. The score for each equal area is the sum of the scores for all zones within that equal area.

[0033] According to the purchase plan for engine hood parts required for insufficient testing, the head shape test area was divided into 18 equal areas. The test management department selected 9 points that might cause significant harm to pedestrians for testing, with no more than 1 point in each equal area. For two equally divided areas that were symmetrically located, one test point was selected. Based on the test results, the score for each test point was determined according to the C-NCAP management rules. The score for the equal area where the test point was located was equal to the score of the test point multiplied by the number of areas in that equal area. For equal areas where no test point was selected, the score for the equal area symmetrical to it was obtained.

[0034] Compared with the prior art, the advantages of the present invention are as follows:

[0035] The present invention provides a design and analysis method for pedestrian protection head shape tests. By conducting pedestrian protection head shape simulation analysis during the engineering design stage, performance scores can be evaluated in advance and performance optimization can be performed to ensure the passability of pedestrian protection head shape performance scores. This avoids the problem that the test vehicle structure may undergo significant deformation after more than two hundred impact tests, which would lead to a decrease in the accuracy and reliability of later test results. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0037] Figure 1 This is a flowchart illustrating the design and analysis method for a pedestrian protection head shape test according to the present invention;

[0038] Figure 2 This is a schematic diagram of the points for designing and analyzing a pedestrian head shape test according to the present invention;

[0039] Figure 3 This is a hard spot distribution map;

[0040] Figure 4 Example graph of damage value chromatogram

[0041] Figure 5 For HIC 15 Damage curve - single peak;

[0042] Figure 6 For HIC 15 Damage curve - bimodal;

[0043] Figure 7 HIC15 damage curve - multi-peak;

[0044] In the picture: 1. Water tank cover, 2. Battery, 3. Engine decorative cover, 4. Tower mount, 5. Distribution box, 6. Front frame, 7. Wiper shaft, 7. Hinge, 8. Vacuum booster pump, 9. Water tank, 10. Air filter, 11. Headlight. Detailed Implementation

[0045] To clearly and completely describe the technical solution and its specific working process of the present invention, the specific embodiments of the present invention are as follows, in conjunction with the accompanying drawings:

[0046] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0047] Example 1

[0048] like Figure 1 The diagram shown is a flowchart illustrating the design and analysis method for a pedestrian protection head shape test according to this embodiment. The method specifically includes the following steps:

[0049] Through pedestrian protection head shape simulation analysis, the scores of head shape performance at all impact points are obtained;

[0050] Representative head impact points, representing one-third of the total head impact points, were selected, and the performance of pedestrian head protection was tested and scored using either the grid point method or the equal area method.

[0051] Example 2

[0052] This embodiment provides a method for designing and analyzing pedestrian head shape tests, which specifically includes the following steps:

[0053] First, obtain the simulation analysis injury values ​​of the pedestrian head impact point, such as... Figure 2 As shown, the scores for all impact points of the head shape performance are available, with 210 impact points. The 5 points between A_13_2 and A_13_-2 in row 13 are the default green "default prediction result grid points," points A_14_8, A_14_-8, A_15_8, and A15_-8 are the default red "default prediction result grid points," there are no "unpredictable result grid points" (blue points), and the remaining points are "specific prediction result grid points." The overall accuracy of this simulation analysis reaches over 90%.

[0054] Secondly, in the simulation analysis results of 201 head impact points, 60 representative head impact points were selected, which is one-third of the total number of head impact points.

[0055] Third, select representative head-shaped impact points; see the example graph of injury value chromatogram. Figure 3 Select according to the following selection rules in sequence:

[0056] Item 1: Green damage chromatogram (HIC) in the center area of ​​the hairpiece 15 Select one point with a value ≤ 600, C_7_1(HIC) 15 =495), this point has no secondary collision with hard points inside the cabin (the damage curve has only one peak), and Figure 5 The curves are consistent, and apart from the inner and outer panels of the hairnet, there are no other structures at this point, such as adhesive or hard spots. This point is assigned 30 points.

[0057] Item 2: Glass area, selected according to the energy absorption space of the head impact point;

[0058] Table 1 shows examples of energy absorption spaces.

[0059]

[0060] The head shape is a red damage spectrum: energy absorption space ≤ 50mm, A_12_6 (HIC) can be selected. 15 =2700, energy absorption space 43mm) and A_12_0(HIC) 15 =2161, energy absorption space 43mm); head shape is brown damage spectrum: 50mm < energy absorption space ≤ 60mm, A_12_5 (HIC) can be selected. 15 =1570, energy absorption space 51mm), or A_12_-5(HIC) 15 =1447, energy absorption space 50mm);

[0061] The head shape is an orange damage spectrum: 60mm < energy absorption space ≤ 75mm, select A_12_4 (HIC) 15 =1115, energy absorption space 61mm) or A_12_-4(HIC) 15 =1113, energy absorption space 61mm), A_13_6(HIC) 15 =1122, energy absorption space 74mm);

[0062] The head shape is yellow with a toxic color spectrum: 75mm < energy absorption space ≤ 90mm, select A_13_-3 (HIC). 15 =666, energy absorption space 89mm), A_12_-1(HIC) 15 =999, energy absorption space 76mm) or A_12_1(HIC) 15 =999, energy absorption space 76mm), A_13_-5(HIC) 15 =777, energy absorption space 76mm);

[0063] The head shape is a green damage spectrum: energy absorption space > 90mm, select A_13_5 (HIC) 15 =621, energy absorption space 94mm);

[0064] The above-mentioned locations are assigned an evaluation score of 30 points.

[0065] Item 3: Wiper area, select at least one head-shaped impact point near each wiper axis. Select A_10_-6(HIC). 15 =1395), A_9_-2(HIC) 15 =973), the above points are assigned an evaluation score of 30 points.

[0066] Item 4: For the sink cover area, select the point with the highest head-on impact damage, the point with the lowest head-on impact damage, and the point where the head-on damage is near the color-jumping threshold. Row 9 is the sink cover area (between A_9_6 and A_9_-6), select the point with the lowest damage, A_9_2 (HIC). 15 =665), the point of maximum damage is A_9_-6 (HIC) 15 =1294), the damage value is near the color-jumping threshold at point A_9_-2 (HIC). 15 =973) and A_9_-3(HIC) 15 =1054). This point is assigned an evaluation score of 30 points. The definition of points near the color-changing threshold is given in item 6.

[0067] Item 5: Headlight area, select a point where the head injury value is near the critical value of the color jump in the color spectrum, and select C_1_-5(HIC). 15 =1630), C_2_-6(HIC) 15 =950), C_3_-7(HIC) 15 =1345) or a symmetrical side point. This point is assigned an evaluation integral of 30 points. The definition of points near the chromatographic color jump threshold is given in item 6.

[0068] Item 6: Select points where the head injury value is near the critical value of the color spectrum jump, with the following requirements:

[0069] The damage spectrum for head-shaped sites is green, HIC 15 Points with a resolution of ≥600 are listed as options. Select A_14_5(HIC). 15 =600) or A_14_-5(HIC) 15 =600), A_10_5(HIC) 15 =630), A_8_2(HIC) 15 =613), C_4_6(HIC) 15 =649) or C_4_-6(HIC) 15 =649), C_5_4(HIC) 15 =649) or C_5_-4(HIC) 15 =649), C_5_3(HIC) 15=625) or C_5_-3(HIC) 15 =625), C_4_3(HIC) 15 =649) or C_4_-3(HIC) 15 =649).

[0070] The lesion spectrum for head-shaped sites is yellow, and 650 < HIC. 15 ≤700 and 950≤HIC 15 Points with a value ≤1000 are listed as options. Select A_13_-4(HIC). 15 =670), C_7_5(HIC) 15 =695) or C_7_-5(HIC) 15 =695), C_6_4(HIC) 15 =668) or C_6_-4(HIC) 15 =685), C_3_2(HIC) 15 =687) or C_3_-2(HIC) 15 =689), C_5_-6(HIC) 15 =670), C_8_7(HIC) 15 =984) or C_8_-7(HIC) 15 =946), C_5_7(HIC) 15 =990) or C_5_-7(HIC) 15 =990), C_2_5(HIC) 15 =989) or C_2_-5(HIC) 15 =980), C_2_-3(HIC) 15 =983).

[0071] The damage spectrum for head-shaped sites is orange, and 1000 < HIC. 15 ≤1100 and 1250≤HIC 15 Points with a value ≤1350 are listed as options. Select A_12_2(HIC). 15 =1021) or A_12_-2(HIC) 15 =1006), C_1_0(HIC) 15 =1044), C_2_4(HIC) 15 =1079) or C_2_-4(HIC) 15 =1083), C_1_2(HIC) 15 =1251) or C_1_-2(HIC) 15 =1258), C_1_3(HIC) 15 =1333), C_0_0(HIC) 15 =1340), C_9_8(HIC)15 =1299), A_10_7(HIC) 15 =1299), A_10_6(HIC) 15 =1040), A_10_4(HIC) 15 =1304), A_10_3(HIC) 15 =1095), A_10_-2(HIC) 15 =1349), A_9_-3(HIC) 15 =1054), A_10_-4(HIC) 15 =1090), A_9_-7(HIC) 15 =1006).

[0072] The lesion spectrum at the head-shaped site is brown, 1350 < HIC 15 ≤1450 and 1600≤HIC 15 Points with a value ≤1700 are listed as options. Select A_11_8(HIC). 15 =1660) or A_11_-8(HIC) 15 =1660), C_8_8(HIC) 15 =1686), A_11_5(HIC) 15 =1688), C_1_-4(HIC) 15 =1600).

[0073] The damage spectrum for head-shaped points is red, 1700 < HIC 15 Points with a resolution ≤1800 are listed as options. Select A_11_4(HIC). 15 =1780).

[0074] Each head shape point that meets the sixth principle is assigned 10 points in the evaluation.

[0075] Item 7: Hard structural areas within the cabin need to be categorized according to different hard structural areas. Head shape injury curves for different zones should be used to evaluate the head shape points, assigning a score of 5 to 10 points to each point. Specifically, the evaluation is based on the z-axis distance between the outer panel of the head cover and the hard structure, with the smallest distance assigned 5 points. The head shape injury curve for the head shape point with the smallest distance also needs to be determined, categorized as follows: Head Shape HIC 15 The damage calculation window may contain one, two, or more peaks. For a single peak, see... Figure 5 0 points; for those with 2 peaks, see Figure 6 Assign 5 points; for those with multiple peaks, see Figure 7 , assigned a value of 5 points.

[0076] The head shape point selection in the hard point structure area is as follows:

[0077] Hinge area: A_10_7(HIC) 15 =1299) and A_10_-7(HIC) 15 =1543), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 7 Consistent.

[0078] Vacuum booster pump: C_7_-2(HIC) 15 =587), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0079] Battery: C_8_5(HIC) 15 =892), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0080] Distribution box: C_5_-6(HIC) 15 =670), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0081] Air filter: C3-4 (HIC) 15 =848), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0082] Water tank: C_6_6(HIC) 15 =874), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0083] Gas spring connection point: C_5_7(HIC) 15 =990) or C_5_-7(HIC) 15 =990), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 7 Consistent.

[0084] Engine trim cover: C_3_2(HIC) 15 =687) or C_3_-2(HIC) 15 =689), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0085] Suspension mount: C_8_-5(HIC) 15 =914), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0086] Front-end framework: C13 (HIC) 15 =1333), the z-axis space is minimized, and the head-shaped damage curve is similar to... Figure 6 Consistent.

[0087] Article 8: If the representative head-shaped impact points selected from the above 7 articles exceed 1 / 3 of the total number of head-shaped impact points, a comprehensive score will be calculated based on the scores of all points, and points will be streamlined after ranking. The streamlining principles are as follows: First, points with severe damage values ​​will be selected from symmetrical areas; second, for critical value points, lower critical value points will be retained first, while upper critical value points will be removed.

[0088] Points 60: A_9_-2, total 1 point;

[0089] Points 40: A_9_-3, total 2 points;

[0090] Points 30: A_13_5, A_13_6, A_13_-3, A_13_-5, A_12_0, A_12_-1 or A_12_1, A_12_4 or A_12_-4, A _12_5 or A_12_-5, A_12_6, A_10_-6, A_9_2, A_9_-6, C_7_1, C_3_-7, C_2_-6, C_1_-5, a total of 19 points;

[0091] Points 20: A_10_7, C_5_-6, C_5_7 or C_5_-7, C_3_2 or C_3_-2, C_1_3, a total of 7 points;

[0092] Points 10: A_14_5 or A_14_-5, A_13_-4, A_12_2 or A_12_-2, A_11_4, A_11_5, A_11_8 or A_11_-8, A_10_-2, A_10_ 3. A_10_4, A_10_-4, A_10_5, A_10_6, A_10_-7, A_9_-7, C_9_8, C_8_8, A_8_2, C_8_5, C_8_-5, C_8_7 or C_8 _-7, C_7_-2, C_7_5 or C_7_-5, C_6_4 or C_6_-4, C_6_6, C_4_6 or C_4_-6, C_5_4 or C_5_-4, C_5_3 or C_5_-3, C_4_3 or C_4_-3, C_3_-4, C_2_-3, C_2_4 or C_2_-4, C_2_5 or C_2_-5, C_1_2 or C_1_-2, C_1_0, C_1_-4, C_0_0, totaling 49 points;

[0093] There are a total of 78 points above, of which 18 need to be streamlined.

[0094] Points removed: A_14_-5, A_12_-2, A_12_-5, A_12_-4, A_12_1, A_11_-8, C_8_-7, C_7_-5, C_6_4, C_5_-3, C_5_-4, C_5_7, C_4_-3, C_4_-6, C_3_2, C_2_4, C_2_-5, C_1_2, for a total of 18 points removed.

[0095] Article 9: Obtain a list of head shape test points that account for 1 / 3 of the total head shape test points.

[0096] A total of 60 test points were selected, as listed below:

[0097] A_14_5, A_13_-3, A_13_-4, A_13_5, A_13_-5, A_13_6, A_12_0, A_12_-1, A_12_2, A_12_4, A_12_5, A_12_6, A_11_4, A_11_ 5. A_11_8, A_10_-2, A_10_3, A_10_4, A_10_-4, A_10_5, A_10_6, A_10_-6, A_10_7, A_10_-7, A_9_2, A_9_-2, A_9_-3, A_9_- 6. A_9_-7, C_9_8, A_8_2, C_8_5, C_8_-5, C_8_7, C_8_8, C_7_1, C_7_-2, C_7_5, C_6_4, C_6_6, C_5_3, C_5_4, C_5_-6, C_5_ 7. C_4_3, C_4_6, C_3_-2, C_3_-4, C_3_-7, C_2_-3, C_2_-4, C_2_5, C_2_-6, C_1_0, C_1_-2, C_1_3, C_1_-4, C_1_-5, C_0_0.

[0098] This embodiment conducts head shape point tests and analyses based on striking 2-3 head shape points with one hair shield and striking a maximum of 2 head shape points (glass position) with one piece of glass.

[0099] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0100] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0101] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method of designing and analyzing a headform test for pedestrian protection, characterized in that, Specifically, the steps include the following: Through pedestrian protection head shape simulation analysis, the scores of head shape performance at all impact points are obtained; Representative head impact points, representing one-third of the total head impact points, were selected, and the pedestrian head protection performance was tested and scored using either the grid point method or the equal area method. The selection of representative head-shaped impact points follows the specific selection rules as follows: A1, the center area of the cover is damaged by the color spectrum HIC 15 The point with a value of less than or equal to 600 is selected as one, and the point has no secondary collision with the hard point in the cabin. A2. Glass area: Selected according to the energy absorption space of the head impact point; A3. Wiper area: Select at least one head-shaped impact point near each wiper axis; A4. Sink cover area: Select the point with the highest head impact damage value, the point with the lowest head impact damage value, and the point where the head damage value is close to the color jump threshold. A5. Headlight area: Select a point where the head injury value is close to the critical value of the color jump in the color spectrum; A6. Select a point where the head injury value is close to the critical value of the color jump in the color spectrum; A7. Hard point structural areas in the cabin: Classified according to different hard point areas, the head shape points are evaluated according to the head shape injury curve of different zones, and each head shape point is given a corresponding evaluation score. In A2, the energy absorption space in the glass region refers to the z-axis space dimension between the glass and the downward z-axis structure of the glass at the head impact point. The energy absorption space in the glass area is segmented according to color zones: Red head color: energy absorption space ≤ 50mm; Brown head color: 50mm < energy absorption space ≤ 60mm; Orange head color: 60mm < energy absorption space ≤ 75mm; Yellow head color: 75mm < energy absorption space ≤ 90mm; Green head color: energy absorption space > 90mm. For each chromatogram, a head-shaped impact point must be selected, and the point where the energy absorption space of each chromatogram is close to the critical point must be selected.

2. A method of designing and analyzing a headform test for pedestrian protection according to claim 1, characterized in that, The test verification of pedestrian head protection performance is specifically carried out by conducting head shape tests and scoring according to the grid point method or the equal area method.

3. A method of designing and analyzing a headform test for pedestrian protection according to claim 1, wherein, In A6, the head point position of the injury spectrum is green, HIC 15 ≥ 600 points are listed as options; the head point position of the injury spectrum is yellow, 650 < HIC 15 ≤ 700 and 950 ≤ HIC 15 ≤ 1000 points are listed as options; the head point position of the injury spectrum is orange, 1000 < HIC 15 ≤ 1100 and 1250 ≤ HIC 15 ≤ 1350 points are listed as options; the head point position of the injury spectrum is brown, 1350 < HIC 15 ≤ 1450 and 1600 ≤ HIC 15 ≤ 1700 points are listed as options; the head point position of the injury spectrum is red, 1700 < HIC 15 ≤ 1800 points are listed as options.

4. A method of designing and analyzing a headform test for pedestrian protection according to claim 1, wherein, If the selected representative head impact points exceed 1 / 3 of the total number of head impact points, a comprehensive score will be calculated based on the scores of all points, and the points will be simplified after ranking.

5. A method of designing and analyzing a headform test for pedestrian protection according to claim 1, wherein, The principles of simplification are as follows: B1. Select points with poor damage values ​​within the symmetrical region; B2. Prioritize retaining the lower critical value point and remove the upper critical value point.

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