A method for calibrating a dummy chest injury index and neck motion deficiency sled

Abstract

The present application relates to the technical field of vehicle safety, in particular to a dummy chest injury index and neck motion defect sliding table calibration method. The method comprises the following steps: a Hybrid III 5th female dummy is placed on the rear seat outside; a data acquisition device is installed on the seat bottom plate, and the fixed point and the retractor on the safety belt are fixed on the bracket; the dummy is placed in a specific temperature and humidity environment for at least 5 hours before the test; a pressure vest is worn, and the spatial relationship between the safety belt and the pressure vest is determined; the safety belt is fastened and the slack is eliminated; the sliding table test scheme parameter combination is set, including pretightening type, limiting force, double limiting force and safety belt position; the real-time safety belt position data provided by the pressure vest is used to determine the shoulder belt position at the moment of maximum chest compression deformation, obtain the key correction coefficient B, quantify the influence of the safety belt position on the chest compression deformation, and determine the chest injury evaluation index. The technical scheme can improve the accuracy and reliability of the chest compression deformation measurement.

Description

Technical Field

[0001] This invention relates to the field of vehicle safety technology, specifically to a method for calibrating the chest injury index and neck movement defect slide of a dummy. Background Technology

[0002] The 25% offset frontal crash test is an extremely rigorous and representative crash test that can accurately simulate the scenario of a small overlap collision between a vehicle and an obstacle on a real road. It places extremely high demands on the structural safety of the vehicle and the assessment of dummy injuries.

[0003] In automotive crash safety testing systems, crash dummies are crucial tools for simulating the forces and injuries experienced by the human body during a collision. Accurate measurement of various injury indicators is essential for evaluating vehicle safety performance and improving vehicle safety design. The Hybrid III 5th female crash dummy, a commonly used test dummy, is widely applied in rear-seat crash safety testing to assess the risk of injury to rear-seat occupants in a collision.

[0004] However, existing technologies have significant limitations in assessing chest injuries in rear-seat Hybrid III 5th generation dummies during a 25% offset frontal crash. Currently, key indicators of chest injury in Hybrid III dummies are measured primarily using a single potentiometer to measure the compression deformation between the sternum and spine. While this method can reflect chest damage to some extent, the chest potentiometer is highly sensitive to the seatbelt load position, making the results susceptible to interference from various factors.

[0005] Specifically, the position of the upper anchor point of the seat belt and its displacement during a collision significantly affect the loading position of the shoulder belt load on the chest. Even slight changes in this loading position can lead to significant deviations in the measurement of chest compression deformation, thus failing to accurately reflect the actual damage to the dummy's chest during a collision.

[0006] According to C-IASI's statistics on 25% frontal offset crash test data over the past three years, over 80% of rear-seat Hybrid III 5th generation dummies experienced seatbelt displacement during the crash. This data indicates that seatbelt displacement is extremely common in actual crash tests, severely affecting the accuracy and reliability of chest compression deformation measurements. Consequently, chest injury assessment indicators derived from these measurements lack sufficient persuasiveness and cannot provide accurate basis for optimizing vehicle safety design. Summary of the Invention

[0007] The purpose of this invention is to propose a method for calibrating the dummy chest injury index and neck movement defects using a slide table, which can improve the accuracy and reliability of chest compression deformation measurement.

[0008] To achieve the above objectives, in a first aspect, the present invention provides a method for calibrating the chest injury index and neck movement defect slide of a dummy, comprising: A female dummy from the Hybrid III 5th generation was used and placed on the outer rear seat. Data acquisition equipment is installed on the seat base, and the collision process is recorded at a speed of no less than 1000 frames per second using an onboard high-speed camera; sensors are equipped on the dummy to measure the acceleration, force, torque, and compression deformation of various parts; data acquisition from the slide and other channels includes seat acceleration, slide acceleration, seat belt force, and pressure vest pressure; The anchor points on the safety belt are fixed to the retractor on the bracket. The position of the safety belt is changed by changing the inner and outer positions. Before the test, the dummy is placed in a specific temperature and humidity environment for at least 5 hours. Wear a pressure vest and determine the spatial relationship between the safety belt and the pressure vest. Fasten the safety belt and eliminate any slack. Perform specific operations on the retractor. Set the parameter combination for the slide test scheme, including preload type, force limiting, double force limiting, and safety belt position; keep the H-point, head center of gravity, and pelvic angle of the dummy consistent in each test; Using the real-time seat belt position data provided by the pressure vest, the shoulder belt position at the moment of maximum chest compression deformation was determined to be consistent with the preset position before the trolley test. The chest compression deformation at the preset stage position was obtained, the key correction coefficient B was obtained, the influence of seat belt position on chest compression deformation was quantified, and the chest injury assessment index was determined by the calculated chest pressure change rate.

[0009] The beneficial effects of the basic approach: By utilizing real-time seatbelt position data provided by the pressure vest and combining it with a carefully designed parameter matrix experiment, a quantitative relationship between seatbelt position changes and chest compression deformation was successfully determined, and a key correction factor B was introduced. This fills the gap in existing technologies for studying this quantitative relationship and provides a more accurate quantitative basis for chest injury assessment.

[0010] Meanwhile, the solution comprehensively considers multiple factors and their combined effects, such as pretensioning, force limiting, and seat belt position. Compared with existing technologies that only consider a single factor, it can more comprehensively and realistically simulate complex actual collision conditions, improve the test method's fidelity to real-world scenarios, and enhance the accuracy and credibility of the evaluation results.

[0011] In addition, a shoulder strap position threshold (>120mm is considered a strangulation defect) was set for the occupant movement defect, providing a clear and operable standard for strangulation judgment, effectively solving the problem of ambiguity in the judgment of existing technologies in this regard, and improving the assessment system for neck movement defects. In practical application, this method achieves more accurate chest injury assessment. By accurately reconstructing the amount of chest compression deformation in a vehicle unaffected by the seatbelt position based on the actual seatbelt location, it enables fair comparisons between different restraint systems, further explores the relationship between chest compression and seatbelt position, and significantly improves the accuracy of chest injury assessment.

[0012] The comprehensive multi-factor testing approach makes this technical solution widely applicable to various vehicle types, and it performs particularly well in the evaluation of rear outer seat dummies and complex collision scenarios. Compared to existing technologies, this method can more reliably assess the risk of chest and neck injuries.

[0013] As a feasible and preferred option, the formula for calculating the rate of change in chest pressure is: Chest pressure change rate = B·(shoulder girdle position - 17mm).

[0014] As a feasible and preferred approach, the formula for calculating the chest injury assessment index is as follows:

[0015] The chest injury assessment index reflects the degree of damage to the dummy's chest during a collision.

[0016] As a feasible preferred solution, a shoulder strap position threshold is set, and when the shoulder strap position is >120mm, the choke buckle defect is identified.

[0017] As a feasible preferred option, the position of the seat belt on the dummy's chest is changed by moving the shoulder strap at the fixed point position in the Y direction. The position of the seat belt varies between 11mm and 120mm above the ball end of the chest potentiometer.

[0018] As a feasible and preferred option, check the seat plate and anchor positions for damage after each test, and replace the entire seat belt assembly after each test.

[0019] As a feasible and preferred approach, a typical full-vehicle small-bias hard impact and sideslip strategy average acceleration collision waveform with typical strength and shape is selected. Based on this typical waveform, a slide test is conducted, focusing on observing the correlation between seatbelt position and chest compression, and verifying the effectiveness of the correction factor B under this unified waveform.

[0020] As a feasible preferred solution, 50 whole vehicle waveforms were collected, including 33 waveforms of hard resistance strategy and 17 waveforms of sideslip strategy. After processing such as bandpass filtering, outlier removal, baseline correction, constraint DTW alignment, and waveform weighted averaging, the typical characteristic average waveform was obtained. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a calibrated slide table method for determining the chest injury index and neck movement defects in a dummy.

[0022] Figure 2 This is a schematic diagram of the data collection area for the pressure vest.

[0023] Figure 3 This is a pre-set test matrix diagram.

[0024] Figure 4 This is a schematic diagram for waveform selection.

[0025] Figure 5 This is a schematic diagram of the average waveform, which is a typical feature of this embodiment. Detailed Implementation

[0026] To make the technical solution and advantages of this application clearer, the technical solution of the present invention will be further described in detail below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are only some embodiments of the present invention, and are only used to explain this application, not to limit it. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be considered isolated; they can be combined with each other to achieve better technical effects. The same reference numerals appearing in the accompanying drawings of the following embodiments represent the same features or components, and can be applied to different embodiments.

[0027] Furthermore, unless otherwise defined, the technical or scientific terms used in this invention description shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains.

[0028] The present invention will now be described in further detail with reference to the accompanying drawings: Reference Figure 1 A method for calibrating the chest injury index and neck movement defects in a dummy using a sliding platform, comprising: Step S100, construct the test system, including: Step S101: Using a Hybrid III 5th female dummy, place it on the outer rear seat. The seat is installed on the sliding platform according to the actual vehicle layout. Determine the "H" point of the seat to ensure that the seat's position and posture are consistent with the actual vehicle. The "H" point is the connection point between the human torso and the thigh. The initial position of the seat belt anchor point is determined based on the coordinates of the rear seat belt anchor point on the vehicle's coordinate system.

[0029] Step S102: Install data acquisition equipment on the seat base plate. Use a vehicle-mounted high-speed camera, mounted on a camera bracket, to record the collision process at a speed of no less than 1000 frames / second. At the same time, the dummy is equipped with sensors to measure parameters such as acceleration, force, torque, and compression deformation of various parts. In this embodiment, the total number of channels reaches 20, so as to comprehensively acquire various mechanical response information of the dummy during the collision process.

[0030] Data acquisition for the slide and other channels includes seat acceleration, slide acceleration, seat belt force, and pressure vest pressure. In this embodiment, the total number of sensor channels is 1733 to obtain comprehensive data from the dummy to the slide as a whole.

[0031] Step S103, determine the slide test waveform, see [link / reference] Figure 4 Fifty vehicle waveforms were collected (including 33 waveforms of hard resistance strategy and 17 waveforms of sideslip strategy). After processing such as bandpass filtering (SAE J211), outlier removal, baseline correction, constraint DTW alignment, and waveform weighted averaging, typical characteristic average waveforms were obtained.

[0032] Step S200, Test preparation process, including: Step S201: Prepare the test fixture. Reinforce the test fixture, including the seat mounting base, seat cushion and backrest, seat belt anchor brackets and camera bracket, retractor and upper anchor point. This ensures that the fixture will not deform or shift due to the enormous force generated by the collision during the test, thus guaranteeing the accuracy of the test results.

[0033] The upper anchor point of the seat belt is fixed to the retractor on the bracket. By changing the Y-axis position of the upper anchor point, the position of the seat belt on the chest is changed to simulate the effect of different seat belt fixing positions on the dummy's chest injury. The seat belt buckle and lower anchor point are matched with the seat to ensure the correct installation and use of the seat belt.

[0034] Before the test, the dummy was placed in a specific temperature and humidity environment for at least 5 hours to simulate the effect of different seat belt positions on the dummy's chest injury.

[0035] The position and posture of the test dummies were located and recorded using a coordinate measuring machine and a 3DH positioning system to ensure that the position and posture of each test dummy on the seat remained consistent, thus making the test results comparable.

[0036] Reference Figure 2Wear the compression vest and ensure proper spacing between the seatbelt and the compression vest. Fasten the seatbelt and eliminate any slack. Pull the shoulder strap webbing out of the retractor and then roll it back in. Repeat this process four times. For seatbelts with retractors on both the shoulder straps and lap belt, repeat the process four times for each retractor to ensure proper functioning of the seatbelt during a collision.

[0037] Step S300: Set up the slide test scheme, including parameter combinations such as pretension type (none, early, late), force limiting (3KN, 4KN, 5.5KN, dual force limiting 4.5 / 7KN), and seat belt position (11mm, 17mm, 27mm, 39mm, 53mm, 67mm, 81mm, 100mm, 120mm). Pretension refers to the initial restraint force applied by the seat belt to the dummy's body at the moment of impact. Different pretension types directly affect the dummy's motion state and chest injury during the collision. Force limiting refers to the maximum force that the seat belt can withstand while restraining the dummy. Different force limiting values ​​will have different degrees of impact on the dummy's chest and neck.

[0038] Reference Figure 3 In this embodiment, a total of 23 sliding table tests were conducted. The position of the seat belt on the dummy's chest was changed by moving the shoulder strap at the fixed point in the Y direction. The position of the seat belt varied between 11mm and 120mm above the ball end of the chest potentiometer. Various possible collision scenarios were simulated by different combinations of parameters.

[0039] The H-point, head center of gravity, and pelvic angle of the dummy are kept consistent in each test to ensure that the dummy's initial state is the same in each test, eliminating interference from other factors and making the test results comparable under different parameter combinations.

[0040] After the test, check the seat plate and anchor for damage. Replace the entire seat belt assembly, including the seat belt buckle, for each test to avoid the impact of wear, deformation and other factors that may occur after multiple uses on the test results, and to ensure that the seat belt performance is consistent for each test.

[0041] Step S400, data processing and analysis, includes: Using real-time seatbelt position data provided by the compression vest, the shoulder strap position at the moment of maximum chest compression deformation is determined, and a key correction coefficient B is obtained to quantify the influence of seatbelt position on chest compression deformation. The formula is as follows: Chest pressure change rate = B * (shoulder strap position - 17mm) The rate of change in chest pressure obtained from the above calculations is used to determine the indicators for assessing chest injuries, as shown in the following formula:

[0042] Chest injury assessment indicators accurately reflect the degree of damage to a dummy's chest during a collision, providing a reference for evaluating vehicle safety performance.

[0043] A shoulder strap position threshold is set; an excessively high seat belt position increases the risk of strangulation, thereby reducing the effectiveness of the restraint system. In this embodiment, strangulation is determined when the shoulder strap position is >120mm.

[0044] Example 2 The key difference between this embodiment and Embodiment 1 lies in the selection of an average acceleration collision waveform representing a small-bias hard impact and sideslip strategy within the vehicle, exhibiting typical strength and shape. This typical waveform is derived through comprehensive analysis of various complex situations that may occur in actual traffic accidents, aiming to conduct tests using a unified benchmark waveform, thereby more efficiently applying the test results to the safety performance evaluation of different vehicle models.

[0045] Based on this typical waveform, a slide test was conducted to observe the correlation between seat belt position and chest compression, verifying the effectiveness of the correction factor B under this unified waveform. This clarifies the universality and accuracy of the calibration method for diverse real-world collision scenarios. In-depth analysis of the typical waveform provides more universal guidance for optimizing automotive safety performance.

[0046] Specifically, to determine the waveform of the slide test, see [link to relevant documentation]. Figure 4 Fifty vehicle waveforms were collected (including 33 waveforms from hard resistance strategies and 17 waveforms from sideslip strategies). After processing including bandpass filtering (SAE J211), outlier removal, baseline correction, constraint DTW alignment, and waveform weighted averaging, a typical characteristic average waveform was obtained. Figure 5 .

[0047] The present invention also provides a dummy chest injury index and neck movement defect slide calibration system, which uses the above-mentioned dummy chest injury index and neck movement defect slide calibration method.

[0048] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor of an electronic device, can implement the steps of the above-described method for calibrating a dummy chest injury index and neck movement defect slide.

[0049] Those skilled in the art will understand that implementing all or part of the process in a method for calibrating a dummy chest injury index and neck movement defects using a slide table can be accomplished by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium. When executed, the program can include the processes of various embodiments of the method for calibrating a dummy chest injury index and neck movement defects using a slide table. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0050] The above content is merely an embodiment of the present invention. Commonly known structures and characteristics of the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can improve and implement this solution based on the guidance provided in this application and their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for calibrating the chest injury index and neck movement defects of a dummy using a sliding platform, characterized in that, include: A female dummy from the Hybrid III 5th generation was used and placed on the outer rear seat. Data acquisition equipment is installed on the seat base, and the collision process is recorded at a speed of no less than 1000 frames per second using an onboard high-speed camera; sensors are equipped on the dummy to measure the acceleration, force, torque, and compression deformation of various parts; data acquisition from the slide and other channels includes seat acceleration, slide acceleration, seat belt force, and pressure vest pressure; The anchor points on the safety belt are fixed to the retractor on the bracket. The position of the safety belt is changed by changing the inner and outer positions. Before the test, the dummy is placed in a specific temperature and humidity environment for at least 5 hours. Wear a pressure vest and determine the spatial relationship between the safety belt and the pressure vest. Fasten the safety belt and eliminate any slack. Perform specific operations on the retractor. Set the parameter combination for the slide test scheme, including preload type, force limiting, double force limiting, and safety belt position; keep the H-point, head center of gravity, and pelvic angle of the dummy consistent in each test; Using the real-time seat belt position data provided by the pressure vest, the shoulder belt position at the moment of maximum chest compression deformation was determined to be consistent with the preset position before the trolley test, and the key correction coefficient B was obtained. The influence of the seat belt position on the chest compression deformation was quantified, and the chest injury assessment index was determined by the calculated chest pressure change rate. The formula for calculating the rate of change of thoracic pressure is: Chest pressure change rate = B·(shoulder strap position - 17mm); The formula for calculating the chest injury assessment indicators is as follows: The chest injury assessment index reflects the degree of damage to the dummy's chest during the collision process; Set a shoulder strap position threshold; when the shoulder strap position is >120mm, determine that the neck buckle is defect 1. The position of the seat belt on the dummy's chest is changed by moving the shoulder strap at the fixed point in the Y direction. The position of the seat belt varies between 11mm and 120mm above the ball end of the chest potentiometer.

2. The method for calibrating the chest injury index and neck movement defects of a dummy using a sliding platform according to claim 1, characterized in that, After the test, check the position of the seat plate and anchor for damage, and replace the entire seat belt assembly after each test.

Images