A method for optimizing a passenger side safety seat

Abstract

The present application relates to the field of automobile safety technology, and particularly relates to a passenger side safety seat optimization method, comprising the following steps: step one: establishing a seat model in simulation software, the seat model having a side airbag inside a backrest, the side airbag being surrounded by foam, and the backrest surface layer being provided with a tear line; step two: setting a point explosion condition for the seat model, performing a simulation test, and optimizing at least one of the tear line position, airbag folding mode and foam parameters through analysis of airbag deployment speed; step three: after the simulation test, producing a sample for subsystem testing, trolley testing and whole vehicle testing, and continuously optimizing the tear line in the test to obtain optimal results. The present application adopts simulation means and proposes a multi-objective optimization scheme, which comprehensively optimizes from three aspects of airbag folding mode, tear line position and foam parameters, so that the side airbag is deployed faster and the safety of passengers is effectively protected.

Description

Technical Field

[0001] This invention relates to the field of automotive safety technology, and more specifically to a method for optimizing passenger-side safety seats. Background Technology

[0002] Side airbags are installed on the sides of the seats. When a collision occurs, the side airbags deploy to isolate the body from hard objects such as doors, thus reducing injuries from side impacts. Therefore, the timely deployment of side airbags is a crucial factor affecting occupant safety. Currently, the tear lines of side airbags on the side of the seat back are arranged rather haphazardly. Improper placement can affect airbag deployment, and there is no optimized solution for side airbag deployment.

[0003] In view of the above problems, the inventors of this invention have finally obtained this invention after a long period of research and practice. Summary of the Invention

[0004] To address at least one aspect of the aforementioned technical problems, the present invention provides a method for optimizing an occupant-side safety seat, which uses simulation to optimize the seat in order to improve the deployment speed of the side airbag.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for optimizing occupant-side child safety seats is provided, including the following steps:

[0007] Step 1: Create a seat model in the simulation software. The seat model has side airbags inside the backrest, foam distributed around the side airbags, and tear lines on the surface of the backrest.

[0008] Step 2: Set the detonation conditions for the seat model and conduct simulation tests. Optimize at least one of the following by analyzing the airbag deployment speed: tear line position, airbag folding method, and foam parameters.

[0009] Step 3: After the simulation test, a prototype is made for subsystem test, trolley test and whole vehicle test, and the tear line is further optimized during the test to obtain the best effect.

[0010] Furthermore, in step one, the establishment of the seat model includes tear line modeling, foam refinement modeling, and airbag modeling.

[0011] Furthermore, in the tear line modeling, the strength of the tear line in different intervals is defined by defining the material of the bar element, and different materials are defined by different stress-strain function curves.

[0012] Furthermore, in the detailed modeling of the foam, different materials are used to distinguish foam blocks with different hardness.

[0013] Furthermore, in the airbag modeling, the airbag folding and opening time is changed by altering the friction coefficient inside the airbag itself.

[0014] Furthermore, in step two, the detonation conditions include the ignition time, which is the time required from the occurrence of the collision to the start of airbag detonation.

[0015] Furthermore, the analysis of airbag deployment speed includes: setting a time threshold required for the airbag to deploy from the initial detonation to just outside the seat, setting a time threshold required for the airbag to fully deploy from the initial detonation, and determining whether the simulation test has reached the threshold.

[0016] Furthermore, optimization of the tear line position includes moving the tear line forward; optimization of the foam parameters includes reducing the foam hardness along the airbag deployment path; and optimization of the airbag folding method includes changing the airbag folding method.

[0017] This invention uses simulation to propose a multi-objective optimization scheme, which comprehensively optimizes the airbag folding method, the position of the tear line, and the parameters of the foam, so that the side airbags can deploy faster, achieving the technical effect of advancing the initial deployment time of the side airbags by 3ms and the overall full deployment time by 7ms, effectively protecting the safety of the occupants. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A structural schematic diagram of a child safety seat and side airbags is shown.

[0020] Figure 2 A schematic diagram of the tear line on the seat back is shown;

[0021] Figure 3 This diagram illustrates the division of foam blocks in refined foam modeling.

[0022] Figure 4 A comparison diagram of the tear line position before and after optimization in one embodiment of the present invention is shown. Detailed Implementation

[0023] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0024] like Figure 1 , Figure 2As shown, the occupant-side safety seat optimization method of the present invention includes a safety seat 1 comprising a backrest 11 and a seat cushion 12, with a side airbag 2 inside the backrest and a tear line 3 on the outer layer of the side wings of the backrest.

[0025] Step 1: Create a seat model in the simulation software. The seat model includes a backrest and a seat cushion. The backrest has tear lines, internal side airbags, and foam distributed around the side airbags.

[0026] Among them, tear line modeling: bar elements are used to simulate tear lines. The strength of tear lines in different intervals is defined by defining the material of the bar elements. Different materials are defined by different stress-strain function curves.

[0027] Detailed foam modeling: The foam in car seat 1 is divided into seat cushion foam, backrest foam, and headrest foam. In reality, these foams use the same material, but the compressive force varies, resulting in foam blocks of different hardness. Generally, the compressive force also varies in different areas of the foam on the side wings of the seat, leading to different levels of injury to the occupant. For example... Figure 3 As shown, during modeling, different materials are used to distinguish these different foam blocks according to the requirements of the specific drawings.

[0028] Airbag modeling: In simulation, changing the friction coefficient inside the airbag can effectively alter the airbag's folding and opening time. This is mainly defined using the CNTAC keyword.

[0029] Step 2: Set the detonation conditions for the seat model, and optimize at least one of the following by analyzing the airbag deployment speed: tear line position, airbag folding method, and foam parameters.

[0030] Regarding the airbag deployment conditions, a corresponding ignition time TTF (time to fire) is set in the simulation environment. For example, when TTF=5ms, it means that the airbag will start to deploy 5ms after the collision occurs. In a real vehicle collision, the airbag deployment will be triggered by sensors after the collision is detected.

[0031] In a preferred embodiment, after the side airbag deploys, it typically emerges from inside the seat after 4-7 ms (the side airbag just begins to deploy from inside the seat), and reaches full deployment within 15-20 ms. The relative displacement between the door panel and the seat is also needed to determine whether the airbag can deploy normally inside the seat. Time thresholds for the side airbag emergence and full deployment are set, and the simulation test is used to determine whether these thresholds are reached.

[0032] If the threshold is not reached, optimize the airbag folding method, such as using a truck-in folding method where the lower end of the airbag deploys faster, and then rebuild the airbag model and conduct a detonation test.

[0033] If the threshold is still not reached, optimize the foam parameters, such as reducing the foam hardness along the airbag deployment path. Then rebuild the foam model and conduct a detonation test.

[0034] If the threshold is still not reached, move the tear line forward, rebuild the tear line model, and conduct a detonation test. If the threshold is still not reached, continue to move the tear line forward until a better effect is achieved.

[0035] It should be noted that the above optimization order is only an example, and the optimization order of the tear line position, airbag folding method and foam parameters is not limited.

[0036] Step 3: After the simulation test, a prototype is made for subsystem test, trolley test and whole vehicle test, and the tear line is further optimized in subsequent tests to obtain the best results.

[0037] In a specific example, the seat model was built using ANSA and UltraEdit software. By optimizing the airbag folding, seat foam stiffness, and seat tear lines, the initial airbag deployment time from inside the seat was advanced by 3ms, the full airbag deployment time from inside the seat was advanced by 7ms, and the dummy's chest deformation was reduced by 2mm.

[0038] The above are merely preferred embodiments of the present invention and are illustrative rather than restrictive. The structure and connection methods of the components in the present invention can be varied, and any equivalent transformations and improvements made based on the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A method for optimizing an occupant-side child safety seat, characterized in that, Includes the following steps: Step 1: Create a seat model in the simulation software. The seat model has side airbags inside the backrest, foam distributed around the side airbags, and tear lines on the surface of the backrest. Step 2: Set the detonation conditions for the seat model and conduct simulation tests. Optimize at least one of the following by analyzing the airbag deployment speed: tear line position, airbag folding method, and foam parameters. Step 3: After the simulation test, a prototype is made for subsystem test, trolley test and whole vehicle test, and the tear line is further optimized during the test to obtain the best effect.

2. The method for optimizing an occupant-side safety seat as described in claim 1, characterized in that, Step one, which involves creating the seat model, includes tear line modeling, foam detailing modeling, and airbag modeling.

3. The method for optimizing an occupant-side safety seat as described in claim 2, characterized in that, In the tear line modeling, the strength of the tear line in different intervals is defined by defining the material of the bar element, and different materials are defined by different stress-strain function curves.

4. The method for optimizing an occupant-side safety seat as described in claim 2, characterized in that, In the detailed modeling of the foam, different materials are used to distinguish foam blocks with different hardness.

5. The method for optimizing an occupant-side safety seat as described in claim 2, characterized in that, In the airbag modeling, the airbag folding and opening time is changed by altering the friction coefficient inside the airbag itself.

6. The method for optimizing an occupant-side safety seat as described in claim 1, characterized in that, In step two, the detonation conditions include the ignition time, which is the time required from the occurrence of the collision to the start of airbag deployment.

7. The method for optimizing an occupant-side safety seat as described in claim 6, characterized in that, The analysis of airbag deployment speed includes: setting a time threshold required for the airbag to deploy from the initial ignition to just being ejected from the seat, setting a time threshold required for the airbag to fully deploy from the initial ignition, and determining whether the simulation test has reached the threshold.

8. The method for optimizing an occupant-side safety seat as described in claim 7, characterized in that, Optimization of the tear line position includes moving the tear line forward; optimization of the foam parameters includes reducing the foam hardness along the airbag deployment path; optimization of the airbag folding method includes changing the airbag folding method.

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