An impact testing method for optimizing the front energy-absorbing foam structure of an active hood.

Abstract

This invention provides an impact testing method for optimizing the energy-absorbing foam structure of the front bumper for active engine hoods. The method includes: based on a whole-vehicle impact simulation model, performing pedestrian leg-shaped and whole-vehicle impact simulations on various areas of the energy-absorbing foam in the front bumper to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole-vehicle impact simulation. Based on the foam impact simulation model, performing foam impact simulations at multiple impact velocities sequentially until the foam compression amount reaches the target compression amount, and using this impact velocity as the target velocity. Simulating the actual installation configuration, the pressure sensor and the foam under test are installed in place, and an impact test is performed on the foam under test at the target velocity, recording the foam deformation and pressure sensor signals. Based on the foam deformation and pressure sensor signals, an optimized foam shape is identified. This invention effectively improves the structural design efficiency of the foam for mounting pressure tube sensors, thereby effectively saving vehicle R&D and manufacturing costs.

Description

Technical Field

[0001] This invention relates to the field of vehicle safety design, and more specifically, to an impact testing method, system, electronic device, and storage medium for optimizing the energy-absorbing foam structure of the front bumper for an active hood. Background Technology

[0002] As market demand increasingly emphasizes vehicle protection for pedestrians, automakers are prompting them to research ways to reduce pedestrian injuries in collisions. Active hood systems are among the most effective measures to reduce pedestrian head injuries, and pressure tube sensors are one of the most commonly used sensors in these systems for detecting pedestrians. Since pressure tube sensors are typically mounted within a foam structure inside the front bumper, the design of the foam structure is crucial to the sensor's ability to quickly acquire pedestrian impact signals.

[0003] Currently, mainstream automakers build full-vehicle collision simulation analysis models during the early design and development stages of vehicles. These models predict pressure sensor signals through simulation, thereby assessing the rationality of the foam structure design. Simultaneously, during the real-vehicle verification stage, the design effectiveness is verified by simulating pedestrian leg impacts against the front bumper or by the vehicle impacting a pedestrian's leg. However, this approach has the following shortcomings: Full-vehicle-level impact simulations struggle to accurately predict pressure sensor signals. Many factors affect the accuracy of full-vehicle collision simulations, such as the acquisition of simulation material parameters (e.g., composite plastics, EPP foam, rubber). Furthermore, the simulation methods for connecting components (e.g., snap-fit ​​connections, riveting, plastic welding) are also crucial factors influencing the accuracy of full-vehicle collision simulations. Therefore, realistically simulating and predicting the pressure signal from the pressure sensor presents a significant challenge for simulation. Summary of the Invention

[0004] This invention addresses the technical problems existing in the prior art by providing an impact test method, system, electronic device, and storage medium for optimizing the energy-absorbing foam structure of the front bumper for active engine hoods. It is mainly used to verify the impact test of the optimal structure of the energy-absorbing foam for the front bumper of active engine hoods, which can effectively improve the structural design efficiency of the foam for mounting pressure tube sensors, thereby effectively saving vehicle research and development and manufacturing costs.

[0005] According to a first aspect of the present invention, an impact testing method is provided for optimizing the front protective energy-absorbing foam structure of an active hood, comprising:

[0006] Based on the whole vehicle impact simulation model, pedestrian leg shape and whole vehicle impact simulations were performed on each area of ​​the energy-absorbing foam of the front bumper to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation.

[0007] Based on the foam impact simulation model, multiple impact velocities are used sequentially to simulate foam impact until the foam compression amount in the simulation results reaches the target compression amount. The impact velocity at this point is then taken as the target velocity.

[0008] The pressure sensor and the foam under test are installed in a way that simulates the actual installation configuration in a vehicle. An impact test is then performed on the foam under test at the target speed, and the foam deformation and pressure sensor signal are recorded.

[0009] The optimal foam shape is determined based on the foam deformation and pressure sensor signals.

[0010] Based on the above technical solution, the present invention can also be improved as follows.

[0011] Optional, the construction of a whole-vehicle impact simulation model includes:

[0012] The energy-absorbing foam of the front bumper is divided into sections along the length direction of the active engine cover. Each section in the length direction is then divided into sections along the thickness direction, so that each section in the thickness direction has foam blocks. The thickness direction and the length direction are perpendicular to the impact direction of the pendulum.

[0013] A vehicle impact simulation model was created based on the actual installation pattern of foam in the vehicle and the zoning results of the foam.

[0014] Optionally, based on the whole-vehicle impact simulation model, pedestrian leg shape and whole-vehicle impact simulations are performed on each area of ​​the energy-absorbing foam in the front bumper to obtain the target compression amount of the foam in each area, including:

[0015] In the whole vehicle impact simulation model, the position of the pedestrian leg impactor is placed according to the C-NCAP test rules, and the initial impact speed is set according to the low threshold speed triggered by the active hood system defined by the vehicle model, so as to simulate the process of pedestrian leg impacting the whole vehicle and / or the whole vehicle impacting the pedestrian leg.

[0016] Simulation calculations are performed based on the solver to obtain the maximum compression of foam in each region, and the maximum compression is saved as the target compression of each region.

[0017] Optional, the construction of the foam impact simulation model includes:

[0018] Based on the actual installation form of foam in the whole vehicle, a corresponding test bench for impact testing of foam is designed.

[0019] A corresponding foam impact simulation model is created based on the test bench.

[0020] Optionally, in the foam impact simulation process, the relative positional relationship between the impact pendulum and the tested foam in the foam impact simulation model is the same as the relative positional relationship between the pedestrian leg-shaped impactor and the tested foam in the whole vehicle impact simulation model.

[0021] Optionally, the test bench includes a vertical rigid wall and a horizontally installed vehicle anti-collision beam; the two ends of the anti-collision beam are installed on the rigid wall, the pressure sensor is installed in the foam under test, and the foam under test is installed and fixed on the anti-collision beam based on the actual installation form of the foam in the whole vehicle.

[0022] Optionally, the deformation of the tested foam during the entire impact test is recorded using an accelerometer; wherein:

[0023] The acceleration sensor is mounted on the impact pendulum and is used to collect and record the acceleration of the impact pendulum during the impact test. It is also used to calculate the amount of penetration of the impact pendulum into the tested foam based on the measured acceleration data. The amount of penetration is the amount of compression of the tested foam.

[0024] Optionally, the deformation of the tested foam during the entire impact test can be recorded using a high-speed camera; wherein:

[0025] At least two high-speed cameras are provided, one on the side and the other directly above the foam being tested, respectively, to acquire images of the relative positional changes between the impact pendulum and the foam being tested, and to analyze the amount of intrusion of the impact pendulum into the foam being tested through the images, wherein the amount of intrusion is the amount of compression of the foam being tested.

[0026] Optionally, finding the optimal foam shape based on the foam deformation and pressure sensor signal includes:

[0027] Impact tests were conducted on multiple groups of foams with different shapes to obtain foam deformation data and pressure sensor signals for each group of foams.

[0028] Compare each set of foam deformation data with its corresponding target compression amount, and select foam shapes whose foam deformation data is not greater than the target compression amount as the initial foam shapes;

[0029] By comparing the pressure sensor signals corresponding to the initial screening foam shapes in each group, the foam shapes with stronger pressure sensor signals are selected as the optimized foam shapes.

[0030] According to a second aspect of the present invention, an impact testing system for optimizing the energy-absorbing foam structure of the front guard for an active hood is provided, comprising:

[0031] The first simulation module is used to perform pedestrian leg shape and whole vehicle impact simulation on each area of ​​the energy-absorbing foam of the front bumper based on the whole vehicle impact simulation model, so as to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation.

[0032] The second simulation module is used to simulate foam impact by using multiple impact velocities sequentially based on the foam impact simulation model until the foam compression amount in the simulation results reaches the target compression amount. The impact velocity at this point is then taken as the target velocity.

[0033] The impact test module is used to simulate the actual installation configuration in a vehicle by installing the pressure sensor and the foam under test in place, conducting an impact test on the foam under test at the target speed, and recording the foam deformation and pressure sensor signal.

[0034] The optimization module is used to find an optimal foam shape based on the foam deformation and pressure sensor signals.

[0035] According to a third aspect of the present invention, an electronic device is provided, including a memory and a processor, wherein the processor is configured to execute a computer management program stored in the memory to implement the steps of the above-described method for optimizing the front energy-absorbing foam structure for an active shield.

[0036] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer management program is stored, wherein when executed by a processor, the computer management program implements the steps of the above-described method for optimizing the impact test of the front energy-absorbing foam structure for the active hood.

[0037] This invention provides an impact testing method, system, electronic equipment, and storage medium for optimizing the energy-absorbing foam structure of the front bumper of the active engine hood. Compared to conducting full-vehicle impact tests, this invention can detect foam styling problems in advance and determine the foam structure that is beneficial to the signal of the active engine hood pressure sensor as early as possible. This avoids the need to troubleshoot and find the root cause of the weak signal one by one after discovering problems in the later full-vehicle tests, which would consume a lot of manpower and time. This invention saves time and effort, reduces the intensity of manual labor, and effectively saves vehicle development costs. Attached Figure Description

[0038] Figure 1 A flowchart of an impact testing method for optimizing the front energy-absorbing foam structure of an active hood is provided by the present invention.

[0039] Figure 2 This is a schematic diagram of a structure in which foam is divided into sections in one embodiment;

[0040] Figure 3 is a schematic diagram of the test bench structure in one embodiment, wherein Figure 3(a) is a side view and Figure 3(b) is a top view;

[0041] Figure 4 This is a schematic diagram showing the positional arrangement of the front-view camera in one embodiment;

[0042] Figure 5 A functional module block diagram of an impact testing system for optimizing the front energy-absorbing foam structure of an active hood, provided by the present invention;

[0043] Figure 6 A schematic diagram of the hardware structure of a possible electronic device provided by the present invention;

[0044] Figure 7 This is a schematic diagram of the hardware structure of a possible computer-readable storage medium provided by the present invention.

[0045] The attached diagram lists the components represented by each number as follows:

[0046] 1. Rigid wall, 2. Foam under test, 3. Impact pendulum, 4. Anti-collision beam, 5. High-speed camera. Detailed Implementation

[0047] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0048] Figure 1 A flowchart of an impact testing method for optimizing the energy-absorbing foam structure of the front guard of an active hood, as provided by this invention, is shown below. Figure 1 As shown, the method includes:

[0049] Based on the whole vehicle impact simulation model, pedestrian leg shape and whole vehicle impact simulations were performed on each area of ​​the energy-absorbing foam of the front bumper to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation.

[0050] Based on the foam impact simulation model, multiple impact velocities are used sequentially to simulate foam impact until the foam compression amount in the simulation results reaches the target compression amount. The impact velocity at this point is then taken as the target velocity.

[0051] The pressure sensor and the foam under test 2 were installed in a way that simulated the actual installation configuration in a vehicle. An impact test was then conducted on the foam under test 2 at the target speed, and the foam deformation and pressure sensor signal were recorded.

[0052] The optimal foam shape is determined based on the foam deformation and pressure sensor signals.

[0053] Understandably, given the deficiencies in the background technology, this invention proposes an impact testing method for optimizing the energy-absorbing foam structure of the front bumper for the active engine hood. First, a full-vehicle impact simulation model is used to obtain the target compression amount of each region of the foam. Second, based on the obtained target compression amount, a foam impact simulation model is used to obtain the target velocity of the impact test. Then, the pressure sensor is installed in the tested foam 2 for a physical impact test. Based on the physical impact test data of several foams with different shapes, optimization is performed to find the foam shape with better test data. Compared to conducting full-vehicle impact tests, this invention can identify foam shape problems in advance, determine the foam structure beneficial to the pressure sensor signal of the active engine hood as early as possible, and avoid the need to troubleshoot and find the root cause of weak signals one by one after discovering problems in later full-vehicle tests, thus avoiding a large amount of manpower and time costs. This invention saves time and effort, reduces manual labor intensity, and effectively saves vehicle development costs.

[0054] In one possible embodiment, step S1, the construction of the whole vehicle impact simulation model, includes:

[0055] The energy-absorbing foam of the front bumper is divided into sections along the length direction of the active engine cover. Each section in the length direction is then divided into sections along the thickness direction, so that each section in the thickness direction has foam blocks. The thickness direction and the length direction are perpendicular to the impact direction of the pendulum.

[0056] A vehicle impact simulation model was created based on the actual installation pattern of foam in the vehicle and the zoning results of the foam.

[0057] It is understandable that, such as Figure 2 As shown in the partition diagram, in this embodiment, the thickness direction can be understood as the height direction of the tested foam 2, or the vertical direction, and the length direction can be understood as the horizontal direction of the foam. Since the impact direction in the impact test is horizontal, the plane formed by the height direction and the length direction of the tested foam 2 is perpendicular to the impact direction of the impact pendulum 3; that is, the aforementioned thickness direction and length direction are mutually perpendicular to the impact direction of the pendulum. Figure 2 In the embodiment shown, the foam 2 to be tested is divided into 8 regions along the length direction and numbered 1 to 8, and the foam 2 to be tested is divided into 3 regions along the thickness direction and numbered A, B, and C. Therefore, after the partitioning is completed, 24 sub-regions are obtained as shown in Table 1.

[0058] Table 1 Partitioning Results

[0059]

[0060] In one possible embodiment, in step S1, the step of performing pedestrian leg shape and whole-vehicle impact simulations on each area of ​​the energy-absorbing foam in the front bumper based on the whole-vehicle impact simulation model to obtain the target compression amount of the foam in each area includes:

[0061] In the whole vehicle impact simulation model, the position of the pedestrian leg impactor is placed according to the C-NCAP test rules, and the initial impact speed is set according to the low threshold speed triggered by the active hood system defined by the vehicle model, so as to simulate the process of pedestrian leg impacting the whole vehicle and / or the whole vehicle impacting the pedestrian leg.

[0062] Simulation calculations are performed based on the solver to obtain the maximum compression of foam in each region, and the maximum compression is saved as the target compression of each region.

[0063] Understandably, based on the actual installation configuration of foam within the vehicle, whole-vehicle impact simulation is performed. By simulating the impact of a pedestrian's leg on the vehicle and / or the vehicle impacting a pedestrian's leg, the maximum compression of the foam corresponding to the tested vehicle's structure is obtained. This maximum compression is then used as the target compression for the next step in the foam impact simulation model. Since impact testing is a destructive test, this step reduces the testing cost and labor intensity of whole-vehicle impact testing.

[0064] In one possible embodiment, step S2, the construction of the foam impact simulation model, includes:

[0065] Based on the actual installation form of foam in the whole vehicle, a corresponding test bench for impact testing of foam is designed.

[0066] A corresponding foam impact simulation model is created based on the test bench.

[0067] It is understood that in this embodiment, the construction of the foam impact simulation model is based on the actual installation form of foam in the whole vehicle, and its simulation results have high accuracy.

[0068] In one possible embodiment, in step S2, during the foam impact simulation, the relative positional relationship between the impact pendulum 3 and the tested foam 2 in the foam impact simulation model is the same as the relative positional relationship between the pedestrian leg-shaped impactor and the tested foam 2 in the whole vehicle impact simulation model.

[0069] Understandably, in the experiment, the functions of the impact pendulum 3 and the pedestrian leg impactor are both to simulate the scenario of a pedestrian's leg colliding with the front bumper of a vehicle during driving. Therefore, the positional relationship between the impact pendulum 3 and the tested foam 2, as well as the positional relationship between the pedestrian leg impactor and the tested foam 2, should be consistent to ensure the accuracy of the test.

[0070] In one possible embodiment, the test bench includes a vertical rigid wall 1 and a horizontally mounted vehicle anti-collision beam 4; both ends of the anti-collision beam 4 are mounted on the rigid wall 1, and the pressure sensor is installed in the foam under test 2, which is fixed to the anti-collision beam 4 based on the actual installation form of the foam in the whole vehicle.

[0071] As can be understood, as shown in the side view of Figure 3(a) and the top view of Figure 3(b), the tested foam 2 simulates its actual installation form in a complete vehicle and is installed on the vehicle's anti-collision beam 4. The pressure sensor used to detect the pressure signal during impact is installed in a preset mounting position in the tested foam 2, and the rigid wall 1 provides structural support for the vehicle's anti-collision beam 4. The test bench replaces the entire vehicle used in the whole vehicle impact test, and its cost is extremely low compared to the whole vehicle, greatly saving the cost of the whole vehicle impact test. Moreover, it is reusable, easy to disassemble and assemble, which also reduces the labor intensity of the test and improves the efficiency of the test.

[0072] In one possible embodiment, in step S3, the deformation of the tested foam 2 throughout the impact test is recorded using an accelerometer; wherein:

[0073] The acceleration sensor is installed on the impact pendulum 3 and is used to collect and record the acceleration of the impact pendulum 3 during the impact test. It is also used to calculate the amount of intrusion of the impact pendulum 3 into the tested foam 2 through the measured acceleration data. The amount of intrusion is the amount of compression of the tested foam 2.

[0074] It is understandable that the acceleration data of the impact pendulum 3 can be measured by the acceleration sensor. By observing the changes in the acceleration data, the displacement of the impact pendulum 3 can be calculated from the state when the impact pendulum 3 just comes into contact with the foam 2 being tested (when the horizontal velocity of the impact pendulum 3 is at its maximum) to the state when it stops (when the horizontal velocity of the impact pendulum 3 is 0). This displacement corresponds to the amount of penetration of the impact pendulum 3 into the foam 2 being tested, which is also the amount of compression of the foam 2 being tested during the impact.

[0075] Because the compression of foam is relatively small, the compression direction can be approximated as horizontal in impact tests. For example, in a test scenario, the measured acceleration is *a*, and after time *t*, the impact pendulum 3 stops moving, its velocity becoming 0. Since the impact pendulum 3 moves in an arc with its connecting line as the radius during the test, its initial velocity is 0, and its final velocity is *v*, which is the velocity of the impact pendulum 3 at the instant it contacts the tested foam 2. Therefore, using the formula mgh = 1 / 2mv... 2 The velocity v can then be calculated. Where m is the mass of the impact pendulum 3, g is the acceleration due to gravity, and h is the change in height of the impact pendulum 3 from the start of its motion until it comes into contact with the measured foam 2.

[0076] After obtaining the initial velocity v at the moment of impact, and based on the acceleration a collected by the accelerometer, the stroke of the impact pendulum 3 during the impact can be calculated using the following formula, which approximates the compression s of the measured foam 2:

[0077] s = v 2 / 2a.

[0078] In one possible embodiment, in step S3, the deformation of the tested foam 2 throughout the impact test is recorded by a high-speed camera 5; wherein:

[0079] like Figure 4 As shown, at least two high-speed cameras 5 are provided. The two high-speed cameras 5 are respectively set to the side and directly above the foam 2 under test. They are used to acquire images of the relative position change between the impact pendulum 3 and the foam 2 under test, and also to analyze the amount of intrusion of the impact pendulum 3 into the foam 2 under test through the images. The amount of intrusion is the amount of compression of the foam 2 under test.

[0080] It is understandable that, in addition to calculating the compression of the tested foam 2 by collecting the acceleration of the impact pendulum 3, the compression of the tested foam 2 can also be measured by image recognition. The principle is as follows: The impact pendulum 3 has high rigidity and is not easily deformed. Therefore, before the impact, the size of the impact pendulum 3 obtained through image recognition is used as a reference size. During the impact process, as the impact pendulum 3 penetrates the tested foam 2, the size of the impact pendulum 3, as identified by image recognition, gradually decreases. The difference between the smallest size of the impact pendulum 3 identified during the impact test and the reference size is the amount of penetration of the impact pendulum 3 into the tested foam 2, which is also the compression of the tested foam 2. High-speed cameras 5 are arranged at both test angles. By comprehensively evaluating the test results using test data from two different angles, the accuracy of the test can be improved.

[0081] In one possible embodiment, step S4, which involves finding the optimal foam shape based on the foam deformation and the pressure sensor signal, includes:

[0082] Impact tests were conducted on multiple groups of foams with different shapes to obtain foam deformation data and pressure sensor signals for each group of foams.

[0083] Compare each set of foam deformation data with its corresponding target compression amount, and select foam shapes whose foam deformation data is not greater than the target compression amount as the initial foam shapes;

[0084] By comparing the pressure sensor signals corresponding to the initial screening foam shapes in each group, the foam shapes with stronger pressure sensor signals are selected as the optimized foam shapes.

[0085] Understandably, each foam design underwent full-vehicle impact simulation and foam impact simulation, followed by physical impact testing on a test bench. The data from each set were then comprehensively compared to select the optimal foam design from the tested foam designs. This optimal foam design was then printed using a 3D printer to obtain the optimal energy-absorbing foam structure for the front bumper.

[0086] Figure 5 This invention provides a structural diagram of an impact testing system for an optimized front-side energy-absorbing foam structure for an active hood, as shown in the embodiment of the invention. Figure 5 As shown, an impact testing system for optimizing the energy-absorbing foam structure of the front guard of an active hood includes a first simulation module, a second simulation module, an impact testing module, and an optimization module, wherein:

[0087] The first simulation module is used to perform pedestrian leg shape and whole vehicle impact simulation on each area of ​​the energy-absorbing foam of the front bumper based on the whole vehicle impact simulation model, so as to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation.

[0088] The second simulation module is used to simulate foam impact by using multiple impact velocities sequentially based on the foam impact simulation model until the foam compression amount in the simulation results reaches the target compression amount. The impact velocity at this point is then taken as the target velocity.

[0089] The impact test module is used to simulate the actual installation configuration in the vehicle, install the pressure sensor and the foam under test 2 in place, conduct an impact test on the foam under test 2 at the target speed, and record the foam deformation and pressure sensor signal.

[0090] The optimization module is used to find an optimal foam shape based on the foam deformation and pressure sensor signals.

[0091] It is understood that the impact testing system for optimizing the front energy-absorbing foam structure of the active hood provided by the present invention corresponds to the impact testing method for optimizing the front energy-absorbing foam structure of the active hood provided in the foregoing embodiments. The relevant technical features of the impact testing system for optimizing the front energy-absorbing foam structure of the active hood can be referred to the relevant technical features of the impact testing method for optimizing the front energy-absorbing foam structure of the active hood, and will not be repeated here.

[0092] Please see Figure 6 , Figure 6 A schematic diagram illustrating an embodiment of the electronic device provided in this invention. For example... Figure 6As shown, this embodiment of the invention provides an electronic device 600, including a memory 610, a processor 620, and a computer program 611 stored in the memory 610 and executable on the processor 620. When the processor 620 executes the computer program 611, it performs the following steps:

[0093] Based on the whole vehicle impact simulation model, pedestrian leg shape and whole vehicle impact simulations were performed on each area of ​​the energy-absorbing foam of the front bumper to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation.

[0094] Based on the foam impact simulation model, multiple impact velocities are used sequentially to simulate foam impact until the foam compression amount in the simulation results reaches the target compression amount. The impact velocity at this point is then taken as the target velocity.

[0095] The pressure sensor and the foam under test 2 were installed in a way that simulated the actual installation configuration in a vehicle. An impact test was then conducted on the foam under test 2 at the target speed, and the foam deformation and pressure sensor signal were recorded.

[0096] The optimal foam shape is determined based on the foam deformation and pressure sensor signals.

[0097] Please see Figure 7 , Figure 7 This is a schematic diagram illustrating an embodiment of a computer-readable storage medium provided by the present invention. (See diagram below.) Figure 7 As shown, this embodiment provides a computer-readable storage medium 700, on which a computer program 711 is stored. When the computer program 711 is executed by a processor, it performs the following steps:

[0098] Based on the whole vehicle impact simulation model, pedestrian leg shape and whole vehicle impact simulations were performed on each area of ​​the energy-absorbing foam of the front bumper to obtain the target compression amount of the foam in each area. The target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation.

[0099] Based on the foam impact simulation model, multiple impact velocities are used sequentially to simulate foam impact until the foam compression amount in the simulation results reaches the target compression amount. The impact velocity at this point is then taken as the target velocity.

[0100] The pressure sensor and the foam under test 2 were installed in a way that simulated the actual installation configuration in a vehicle. An impact test was then conducted on the foam under test 2 at the target speed, and the foam deformation and pressure sensor signal were recorded.

[0101] The optimal foam shape is determined based on the foam deformation and pressure sensor signals.

[0102] This invention provides an impact testing method, system, and storage medium for optimizing the energy-absorbing foam structure of the front bumper for the active engine hood. Compared to conducting full-vehicle impact tests, this invention can detect foam styling problems in advance and determine the foam structure that is beneficial to the signal of the active engine hood pressure sensor as early as possible. This avoids the need to troubleshoot and find the root cause of the weak signal one by one after discovering problems in the later full-vehicle tests, which would consume a lot of manpower and time. This invention saves time and effort, reduces the intensity of manual labor, and effectively saves vehicle development costs.

[0103] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0104] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0105] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0106] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0107] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0108] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0109] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method of optimizing impact testing of a front bumper beam energy absorbing foam structure for a hood, characterized by, The method comprises the following steps: constructing a whole vehicle impact simulation model, specifically including: dividing the energy-absorbing foam of the front bumper of the active hood in the length direction, and re-dividing each area divided in the length direction in the thickness direction, so that each area in the thickness direction has a foam block, wherein the thickness direction and the length direction are perpendicular to the impact direction of the pendulum; creating a whole vehicle impact simulation model based on the actual installation form of the foam in the whole vehicle and the division result of the foam; based on the whole vehicle impact simulation model, respectively simulating the pedestrian leg type and the whole vehicle impact for each area of the front bumper energy-absorbing foam to obtain the target compression amount of each area of the foam, the target compression amount being the maximum compression amount of the foam in the whole vehicle impact simulation; based on the foam impact simulation model, foam impact simulation is carried out in turn with multiple impact speeds until the foam compression amount in the simulation result reaches the target compression amount, and the impact speed at this time is taken as the target speed; simulating the actual installation form in the whole vehicle to install the pressure sensor and the measured foam in place, and carrying out impact test on the measured foam with the target speed and recording the foam deformation and the pressure sensor signal; finding out the optimized foam shape according to the foam deformation and the pressure sensor signal.

2. A method of optimizing the impact test of a front bumper beam absorbing energy foam structure for a hood as claimed in claim 1, characterized in that, The method of simulating the pedestrian leg type and the whole vehicle impact for each area of the front bumper energy-absorbing foam based on the whole vehicle impact simulation model to obtain the target compression amount of each area of the foam comprises: in the whole vehicle impact simulation model, the position of the pedestrian leg type impactor is placed based on the C-NCAP test rules, and the initial impact speed is set according to the low threshold speed triggered by the active hood system defined by the vehicle type, to simulate the process of the pedestrian leg type impacting the whole vehicle and / or the whole vehicle impacting the pedestrian leg type; the maximum compression amount of each area of the foam is obtained by simulation calculation based on the solver, and the maximum compression amount is saved as the target compression amount of each area.

3. A method of optimizing the impact test of a front bumper beam absorbing energy foam structure for a hood as claimed in claim 1, characterized in that, The construction of the foam impact simulation model comprises: based on the actual installation form of the foam in the whole vehicle, a corresponding test bench for impact test on the foam is designed; a corresponding foam impact simulation model is created based on the test bench.

4. A method of optimizing the impact test of a front bumper beam absorbing energy foam structure for a hood as claimed in claim 2, characterized in that, In the foam impact simulation process, the relative position relationship between the impact pendulum and the measured foam in the foam impact simulation model is the same as the relative position relationship between the pedestrian leg type impactor and the measured foam in the whole vehicle impact simulation model.

5. A method of optimizing the impact test of a front bumper beam absorbing energy foam structure for a hood as claimed in claim 3, characterized in that, The test bench comprises a vertical rigid wall and a horizontally installed vehicle anti-collision cross beam; the two ends of the anti-collision cross beam are installed on the rigid wall, and the pressure sensor is installed in the measured foam, and the measured foam is installed and fixed on the anti-collision cross beam based on the actual installation form of the foam in the whole vehicle.

6. A method of optimizing impact test of a front bumper beam foam structure for a hood as claimed in claim 1, wherein, The deformation of the measured foam in the whole impact test is recorded by an acceleration sensor; wherein: the acceleration sensor is arranged on the impact pendulum, which is used to collect and record the acceleration of the impact pendulum during the impact test, and is also used to calculate the intrusion amount of the impact pendulum to the measured foam through the measured acceleration data, the intrusion amount being the compression amount of the measured foam.

7. A method of optimizing the impact test of a front bumper beam absorbing energy foam structure for a hood according to claim 1 or 6, characterized in that, The deformation of the measured foam in the whole impact test is recorded by a high-speed camera; wherein: At least two high-speed cameras are provided, and the two high-speed cameras are arranged at the side and directly above the measured foam respectively, and are used to acquire images of the relative position changes between the impact pendulum and the measured foam, and are also used to analyze the intrusion amount of the impact pendulum to the measured foam through the images, and the intrusion amount is the compression amount of the measured foam.

8. A method of optimizing impact test of a front bumper beam foam structure for a hood as claimed in claim 1, wherein, The method for finding out the optimized foam shape according to the foam deformation and the pressure sensor signal comprises the following steps of: Performing impact tests on a plurality of groups of foams with different shapes respectively to obtain foam deformation data and pressure sensor signals corresponding to the plurality of groups of foams; Comparing the foam deformation data of each group with the corresponding target compression amount, and screening out foam shapes with foam deformation data not greater than the target compression amount as preliminary screened foam shapes; Comparing the pressure sensor signals corresponding to the preliminary screened foam shapes of each group, and screening out foam shapes with stronger pressure sensor signals as the optimized foam shapes.

9. An impact test system for optimizing a front bumper energy absorbing foam structure for a hood, characterized by, The method comprises the following steps of: A first simulation module is used to construct a whole vehicle impact simulation model, and specifically comprises the following steps: partitioning the energy-absorbing foam of the front bumper of the active hood in the length direction, and further partitioning each region in the length direction in the thickness direction, so that each region in the thickness direction has a foam block, wherein the thickness direction and the length direction are perpendicular to the impact direction of the pendulum; and creating a whole vehicle impact simulation model based on the actual installation form of the foam in the whole vehicle and the partitioning result of the foam; The method is also used to perform pedestrian leg type and whole vehicle impact simulation on each region of the energy-absorbing foam of the front bumper based on the whole vehicle impact simulation model, so as to obtain a target compression amount of the foam in each region, and the target compression amount is the maximum compression amount of the foam in the whole vehicle impact simulation; A second simulation module is used to perform foam impact simulation by using a plurality of impact speeds in turn based on the foam impact simulation model until the foam compression amount in the simulation result reaches the target compression amount, and the impact speed at this time is taken as a target speed; An impact test module is used to simulate the actual installation form in the whole vehicle to install a pressure sensor and a measured foam in place, to perform an impact test on the measured foam by using the target speed, and to record the foam deformation and the pressure sensor signal; An optimization module is used to find out an optimized foam shape according to the foam deformation and the pressure sensor signal.

Images