Zero-gravity seat collision safety virtual test evaluation method, system and equipment

Abstract

The invention provides a zero-gravity seat collision safety virtual test evaluation method, system and device, and belongs to the technical field of vehicles, and the method comprises the steps: constructing a zero-gravity seat finite element model based on a to-be-tested and evaluated zero-gravity seat, and building a virtual sliding table test environment based on a first constraint condition of the zero-gravity seat; a second constraint condition based on a human body finite element model is generated according to the first constraint condition, the posture of the human body finite element model is adjusted through the second constraint condition, and a virtual sliding table testing environment is coupled and matched, so that virtual calculation testing is conducted; and based on the virtual calculation test result, extracting to-be-analyzed data of dynamic data, biomechanical data and motion animation data based on the human body finite element model, analyzing the to-be-analyzed data, and outputting a safety virtual test evaluation result based on human body motion and human body injury. According to the invention, the limitation that the existing physical test dummy cannot meet the requirement of a large-dip-angle test posture is effectively solved, and the collision safety test scene is expanded.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a zero-gravity seat collision safety virtual test evaluation method, system and equipment. Background Art

[0002] With the development of autonomous driving technology, the demand for riding comfort and personalization by passengers in the car is increasing. Studies have shown that a reclining sitting posture, especially a "zero-gravity" posture, helps passengers rest and relax in the car. Zero-gravity seats with adjustable leg rests, backrests and seat cushions are currently a hot spot in vehicle passenger compartment design. However, existing autonomous driving technology cannot completely avoid collision accidents. The safety of zero-gravity seats in vehicle collisions needs to be evaluated urgently.

[0003] The safety evaluation of existing seats and their associated restraint systems mainly relies on physical testing of the whole vehicle and slide based on crash test dummies. However, the existing mature crash test dummies are mainly developed based on upright sitting postures, and cannot match the seats well in a reclining posture with a large inclination angle. Virtual testing based on the finite element method has well solved the limitations of tools and boundary conditions in physical testing. In particular, in virtual testing tools, the human finite element model and the real human body have the same physiological structure and material properties, and have higher biological fidelity than dummies. Collision safety testing and evaluation methods based on the finite element model of the human body are an important direction for future vehicle safety testing.

[0004] Therefore, we propose a zero-gravity seat collision safety virtual testing and evaluation method, system and equipment. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a zero-gravity seat collision safety virtual test evaluation method, system and equipment, aiming to solve the technical problem in the prior art that the collision safety of the zero-gravity seat cannot be comprehensively evaluated.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a zero-gravity seat collision safety virtual test evaluation method, the evaluation method comprising the following steps:

[0008] Construct a finite element model of the zero-gravity seat to be tested and evaluated, and build a virtual slide test environment based on the first constraint condition of the zero-gravity seat;

[0009] In the virtual slide test environment, generating a second constraint condition based on a human finite element model according to the first constraint condition, adjusting the posture of the human finite element model through the second constraint condition and coupling and matching the virtual slide test environment to perform a virtual computing test;

[0010] Based on the virtual calculation test results, extract the data to be analyzed based on the dynamic data, biomechanical data and motion animation data of the human finite element model, analyze the data to be analyzed and output the safety virtual test evaluation results based on human motion and human injury;

[0011] Among them, the first constraint condition includes the seat back angle Angle (BA) based on the angle between the line connecting the upper edge feature point of the seat back frame and the backrest rotation center and the vertical plane, the zero gravity seat cushion angle Angle (CA) based on the angle between the line connecting the front edge feature point of the seat cushion frame and the cushion rotation center and the horizontal plane, and the seat leg support angle Angle (LSA) based on the angle between the line connecting the lower edge feature point of the seat leg support frame and the leg support rotation center and the vertical plane; the second constraint includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle based on the human body finite element model.

[0012] According to the above technical means, since a test environment is constructed, the zero-gravity seat finite element model needs to be constructed as a whole in the test environment. In order to obtain effective evaluation results, the constraint system of the seat finite element model also needs to be deployed.

[0013] Furthermore, the step of constructing a finite element model of the zero-gravity seat to be tested and evaluated further includes, when constructing the finite element model of the zero-gravity seat to be tested and evaluated, determining whether there is an auxiliary restraint system of the zero-gravity seat to be tested and evaluated, and if not, calling a pre-stored standard seat belt restraint system;

[0014] Among them, the zero-gravity seat finite element model at least includes the zero-gravity seat model size and mass data based on the seat frame, seat cushion, backrest, headrest and leg support structure; the auxiliary restraint system at least includes a seat belt, a fixing device and a seat cushion airbag structure; the fixed point position of the standard seat belt restraint system is rapidly adjusted based on the spatial coordinate control parameters.

[0015] According to the above technical means, in order to achieve test results that are more in line with actual applications, the constructed seat finite element model needs to have the same functional structure as the actual seat, including size and mass, so as to improve the effectiveness of the seat finite element model.

[0016] Further, the step of building a virtual slide test environment based on the first constraint condition of the zero-gravity seat also includes confirming that the zero-gravity seat in the zero-gravity seat finite element model matches the functional position of the auxiliary restraint system or the standard seat belt restraint system, wherein the functional position at least includes the seat H point, the seat cushion angle, the seat back angle, the seat leg support angle, the position of the seat belt D ring, the position of the seat belt buckle and the position of the seat belt anchor point;

[0017] The safety belt D-ring is rigidly coupled to the zero-gravity seat back frame to be tested and evaluated, and the outer buckle of the safety belt buckle and the inner anchor point of the safety belt anchor point are rigidly coupled to the zero-gravity seat cushion frame.

[0018] According to the above technical means, the construction of the seat finite element model needs to be matched with the human body finite element model, so as to obtain the evaluation results about the personnel in the human body model. Therefore, the human body finite element model also needs to set corresponding constraints.

[0019] Further, the step of generating a second constraint condition based on the human body finite element model according to the first constraint condition includes inputting the first constraint condition into the following formula to generate a second constraint condition:

[0020] The target pelvic angle is expressed as the angle between the pelvis and the vertical plane: Angle(Pelvis)=55.5+0.33*Angle(BA);

[0021] The torso angle is expressed as the angle between the shoulder-H point line and the vertical plane: Angle (Torso) = -7.5 + 0.86 * Angle (BA);

[0022] The lumbar angle is expressed as the angle between the lumbar spine and the vertical plane: Angle (Lumbar) = 2.3 + 0.59 * Angle (BA);

[0023] The thigh angle is expressed as the angle between the thigh and the horizontal plane: Angle (Thigh) = 9.5 + Angle (CA);

[0024] The shank angle is expressed as the angle between the shank and the horizontal plane: Angle(Leg)=9.5+Angle(LSA).

[0025] According to the above technical means, in order to obtain effective test results during the test process, the human body finite element model in the virtual test environment needs to be coupled with the seat model, so that the test results can be better applied to the actual seat.

[0026] Further, the step of adjusting the posture of the human finite element model through the second constraint condition and coupling and matching the virtual slide test environment to perform a virtual computing test includes:

[0027] Decomposing each angle in the second constraint condition to generate hinge angles corresponding to the human finite element model, so as to transform the standard human finite element posture of the initial upright posture into a customized target lying posture, and coupling it with the zero-gravity chair finite element model;

[0028] After matching the corresponding H-point position, a natural indentation is formed on the seat and cushion back of the zero-gravity seat, and the matching of the seat belt is completed;

[0029] After completing the matching of the virtual slide test environment, input the standard frontal 50% overlapping moving progressive deformation barrier collision MPDB waveform, and perform the virtual calculation test after setting the virtual calculation test parameters.

[0030] According to the above-mentioned technical means, after the virtual calculation test is completed, it is necessary to evaluate the effectiveness of the calculation, and then perform corresponding data extraction after meeting the effectiveness requirements. The purpose is to obtain effective evaluation calculation results based on dynamics, biomechanics and motion animation data.

[0031] Further, extracting the dynamic data, biomechanical data and dynamic data from the finite element model of the human body includes:

[0032] X-direction and synthetic acceleration-time history curves and peak values ​​at the center of mass of the head and point H of the pelvis;

[0033] The time history curves and peak values ​​of the axial force Fz, lateral shear force Fy, flexion moment My and lateral flexion moment Mx of the cervical vertebral body section;

[0034] The peak values ​​of the axial force Fz and the flexion moment My of the thoracic and lumbar vertebral sections;

[0035] Axial force Fz-time history curve and peak value at the iliac crest section;

[0036] The biomechanical data include:

[0037] Spine: First principal strain MPS of vertebral cortical bone in cervical, thoracic and lumbar spine CS , MPS TS and MPS LS Peak value;

[0038] Chest and abdomen: effective plastic strain EPPS of sternum, ribs and pelvic cortical bones ST , EPPS RB and EPPS PL Peak value, VonS stress of heart, lung, spleen, liver, large and small intestine HE , VonS LU , VonS LI and VonS IN Peak value;

[0039] Lower limbs: effective plastic strain EPPS of femur, tibia, and fibula cortical bones FE , EPPS TI and EPPS FI Peak value; first principal strain MPS of knee ligament LG Peak value;

[0040] The motion animation data includes pictures of front viewing angle, left and right side viewing angles, top viewing angle and left and right test 50% cross-sectional viewing angles, wherein the frame rate is not less than 1000fps.

[0041] According to the above technical means, as an important data support for the evaluation of human motion, the data analysis results are of reference significance for the evaluation of human motion.

[0042] Further, the step of analyzing the data to be analyzed and outputting a safety virtual test evaluation result based on human motion comprises:

[0043] Extracting abnormal contact between the shoulder strap of the seat belt and the neck in the motion animation data of the front view and the top view from the data to be analyzed, and abnormal peaks appear in the time history curves of the cervical lateral shear force Fy and the lateral bending moment Mx in the dynamic data, and outputting an evaluation result based on the "strangulation" phenomenon and deducting a preset score;

[0044] Abnormal contact between the seat belt and the abdomen in the animations of the left and right side perspectives and the front perspective in the motion animation data is extracted from the data to be analyzed, and an abnormal falling edge appears in the axial force Fz time history curve at the iliac crest section in the dynamic data, then the evaluation result based on the "diving" phenomenon and recorded as "poor" is output.

[0045] According to the above-mentioned technical means, the purpose of human body injury assessment is to analyze the evaluation content of various parts of the human body through testing, and then conduct an overall analysis of the evaluation results of each part to obtain the overall evaluation result. The analysis and evaluation from part to whole effectively improves the accuracy and rationality of the test results.

[0046] Further, the step of outputting the safety virtual test evaluation result of human body injury after analyzing the data to be analyzed includes:

[0047] The dynamic data and biomechanical data in the data to be analyzed are extracted and the test evaluation results of different parts based on the finite element model of the human body are output through the following model:

[0048] Head: SCROE HEAD =0.3*SC(HIC 15 )+0.3*SC(MPS SK )+0.2*SC(PRESBR )+0.2*SC(VonS BR )

[0049] Spine: SCROE SPINE =0.2*SC(N ij )+0.3*SC(L ij )+0.15*SC(MPS CS )+0.15*SC(MPS TS )+

[0050] 0.2*SC(MPS LS )

[0051] - Torso: SCROE TORSO =0.2*SC(EPPS ST )+0.3*SC(EPPS RB )+0.2*SC(EPPS PL )+0.15*SC(VonS HE )+0.05*SC(VonS LU )+0.05*SC(VonS LI )+0.05*SC(VonS IN )

[0052] Legs: SCROE LEG =0.25*SC(EPPS FE )+0.25*SC(EPPS TI )+0.25*SC(EPPS FI )+0.25*SC(MPS LG )

[0053] The evaluation results of the body part test are input into the following formula to obtain the safety virtual test evaluation results of human body injury:

[0054] SCROE INJURY =0.3*SCROE HEAD +0.3*SCROE SPINE +0.2*SCROE TORSO +0.2*SCROE LEG .

[0055] In a second aspect, the present invention further proposes a zero-gravity seat collision safety virtual test evaluation system, the evaluation system is applied to the evaluation method of the first aspect, the system comprising:

[0056] A construction module is used to construct a finite element model of a zero-gravity seat to be tested and evaluated, and to build a virtual slide test environment based on the first constraint condition of the zero-gravity seat;

[0057] A first processing module is used to generate a second constraint condition based on a human finite element model according to the first constraint condition in the virtual slide test environment, adjust the posture of the human finite element model through the second constraint condition and couple and match the virtual slide test environment to perform a virtual computing test;

[0058] A second processing module is used to extract the data to be analyzed based on the dynamic data, biomechanical data and motion animation data of the human finite element model based on the virtual calculation test results, and output the safety virtual test evaluation results based on human motion and human injury after analyzing the data to be analyzed;

[0059] Among them, the first constraint condition includes the seat back angle Angle (BA) based on the angle between the line connecting the upper edge feature point of the seat back frame and the backrest rotation center and the vertical plane, the zero gravity seat cushion angle Angle (CA) based on the angle between the line connecting the front edge feature point of the seat cushion frame and the cushion rotation center and the horizontal plane, and the seat leg support angle Angle (LSA) based on the angle between the line connecting the lower edge feature point of the seat leg support frame and the leg support rotation center and the vertical plane; the second constraint includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle based on the human body finite element model.

[0060] In a third aspect, the present invention further provides an electronic device, the device comprising:

[0061] at least one processor;

[0062] And, a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to implement the zero-gravity seat collision safety virtual test evaluation method described in the first aspect.

[0063] Beneficial effects of the present invention:

[0064] The present invention proposes a virtual test and evaluation method, system and equipment for zero-gravity seat collision safety, which are used to comprehensively evaluate the safety of zero-gravity seat products during a collision from the two aspects of human movement and human injury. It effectively solves the limitation that existing physical test dummies cannot meet the requirements of large-angle test postures, and expands the collision safety test scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 It is a schematic diagram of the process of the virtual test and evaluation method for zero-gravity seat collision safety of the present invention;

[0066] Figure 2 It is a technical trend diagram of the virtual test evaluation method for zero-gravity seat collision safety of the present invention;

[0067] Figure 3 It is an overall evaluation framework diagram of the zero-gravity seat collision safety virtual test evaluation method of the present invention;

[0068] Figure 4 This is a framework diagram of the zero-gravity seat collision safety virtual test and evaluation system of the present invention. DETAILED DESCRIPTION

[0069] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0070] This embodiment provides a zero-gravity seat collision safety virtual test evaluation method, which effectively solves the limitation that the existing physical test dummies cannot meet the requirements of large-angle test postures, and expands the collision safety test scenarios.

[0071] Figure 1 The process of the virtual test evaluation method for zero-gravity seat collision safety is shown as follows: Figure 1 As shown, the zero-gravity seat collision safety virtual test evaluation method includes the following steps:

[0072] Step S101. Construct a finite element model of a zero-gravity seat to be tested and evaluated, and build a virtual slide test environment based on the first constraint condition of the zero-gravity seat;

[0073] Step S102. In the virtual slide test environment, a second constraint condition based on a human finite element model is generated according to the first constraint condition, and the posture of the human finite element model is adjusted by the second constraint condition and coupled to match the virtual slide test environment to perform a virtual computing test;

[0074] Step S103. Based on the virtual calculation test results, extract the data to be analyzed based on the dynamic data, biomechanical data and motion animation data of the human finite element model, analyze the data to be analyzed and output the safety virtual test evaluation results based on human motion and human injury;

[0075] Among them, the first constraint condition includes the seat back angle Angle (BA) based on the angle between the line connecting the upper edge feature point of the seat back frame and the backrest rotation center and the vertical plane, the zero gravity seat cushion angle Angle (CA) based on the angle between the line connecting the front edge feature point of the seat cushion frame and the cushion rotation center and the horizontal plane, and the seat leg support angle Angle (LSA) based on the angle between the line connecting the lower edge feature point of the seat leg support frame and the leg support rotation center and the vertical plane; the second constraint includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle based on the human body finite element model.

[0076] When constructing a finite element model of a zero-gravity seat to be tested and evaluated, the finite element model of the zero-gravity seat must have the same functional structure, size and mass as the actual seat, including but not limited to detailed seat brackets, cushions, backrests, headrests and leg rest structures. A response comparison between the model and the actual seat under the same boundary conditions must be provided to demonstrate the validity of the finite element model of the zero-gravity seat.

[0077] like Figure 2 As shown, in this embodiment, a finite element model of a zero-gravity seat to be tested and evaluated is constructed, and a virtual slide test environment based on the first constraint condition of the zero-gravity seat is built. It is also necessary to analyze the constraint system of the constructed zero-gravity seat finite element model.

[0078] If the zero-gravity seat to be tested includes a supporting auxiliary restraint system, its finite element model must have the same functional structure as the actual object, including but not limited to seat belts and fixing devices, seat cushion airbag structure; the supporting auxiliary restraint system must provide a response comparison between the model and the actual object under the same boundary conditions to prove the validity of the finite element model.

[0079] If the zero-gravity seat does not include a matching restraint system, a unified finite element model of a standard seat belt restraint system for testing is used. The fixed point position of the standard seat belt restraint system can be quickly adjusted based on the spatial coordinate control parameters. By inputting the spatial coordinates of the characteristic points of the seat to be tested, the position of the corresponding restraint system seat belt D-ring, the position of the seat belt buckle and the position of the seat belt anchor point can be determined, and the matching can be automatically adjusted.

[0080] In this embodiment, a seat finite element model is constructed and tested to obtain test results. The test object needs to be clarified. Therefore, this embodiment sets a first constraint condition and performs calculation and analysis based on the first constraint condition. In this embodiment, the first constraint condition is set as:

[0081] The angle between the line connecting the upper edge feature point of the seat back frame and the rotation center of the seat back and the vertical plane is the seat back angle Angle (BA);

[0082] The angle between the line connecting the front edge feature point of the seat cushion frame and the rotation center of the seat cushion and the horizontal plane is the zero-gravity seat cushion angle Angle (CA);

[0083] The angle between the line connecting the characteristic point of the lower edge of the seat leg support frame and the rotation center of the leg support and the vertical plane is the seat leg support angle Angle (LSA).

[0084] It should be noted that after the first constraint condition is set, it is necessary to confirm that the functional structures of the zero-gravity seat and restraint system finite element model are in the design position, including but not limited to the seat H point, seat cushion angle, seat back angle, seat leg support angle, seat belt D-ring position, seat belt buckle position and seat belt anchor point position; rigidly couple the seat belt D-ring with the zero-gravity seat back frame to be tested, and rigidly couple the outer buckle and inner anchor point with the zero-gravity seat cushion frame.

[0085] The process of building the virtual slide test environment is completed above. The matching coupling part of the human body finite element model and the zero-gravity seat finite element model in step S102 is described below.

[0086] In step S102, in order to achieve matching coupling between the human body finite element model and the zero-gravity chair finite element model, a second constraint condition is set, wherein the second constraint condition includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle of the standard human body finite element model, and the second constraint condition is performed under the first constraint condition, which is specifically expressed as follows:

[0087] The target pelvic angle is expressed as the angle between the pelvis and the vertical plane: Angle(Pelvis)=55.5+0.33*Angle(BA);

[0088] The torso angle is expressed as the angle between the shoulder-H point line and the vertical plane: Angle (Torso) = -7.5 + 0.86 * Angle (BA);

[0089] The lumbar angle is expressed as the angle between the lumbar spine and the vertical plane: Angle (Lumbar) = 2.3 + 0.59 * Angle (BA);

[0090] The thigh angle is expressed as the angle between the thigh and the horizontal plane: Angle (Thigh) = 9.5 + Angle (CA);

[0091] The shank angle is expressed as the angle between the shank and the horizontal plane: Angle(Leg)=9.5+Angle(LSA).

[0092] In this embodiment, each angle in the second constraint condition is decomposed to obtain the corresponding hinge angles of the cervical vertebra, thoracic vertebra, lumbar vertebra, hip joint, knee joint, etc., and the standard human finite element model posture in the initial upright sitting posture is transformed into a customized target lying posture through the dummy-tree function configured in the human body model posture adjustment software Oasys Primer.

[0093] The standard human finite element model is coupled with the zero-gravity seat model through gravity settlement, forced displacement and contact, and the H-point position of the human finite element model is matched with the H-pad position of the seat. At the same time, natural indentations are formed on the seat and the seat cushion back. The shoulders, waist belts and the standard human finite element model are matched through the seat belt adjustment software, so that the shoulder straps of the seat belts fit well with the shoulder and chest surfaces of the model, and the waist belts of the seat belts fit well with the abdomen and hip surfaces.

[0094] It should be noted that in this embodiment, the safety test evaluation results are achieved, so the data to be analyzed needs to be pre-set, and the analysis can only be performed after the corresponding data is obtained. Therefore, in this embodiment, the human finite element model dynamics data and biomechanical data are outputted as follows.

[0095] The output settings of the human finite element model dynamics data include:

[0096] Establish marked nodes at the center of mass of the head and the H point of the pelvis to output local acceleration.

[0097] The DYNA keyword is *DATABASE_HISTORY_NODE.

[0098] Load cells are established at the mid-section of the vertebral bodies of the cervical vertebrae (C1-C7), thoracic vertebrae (T1-T12), and lumbar vertebrae (L1-L5) to output forces and moments in the XYZ directions.

[0099] The DYNA keyword is *DATABASE_CROSS_SECTION.

[0100] A load unit is established in the front area of ​​the iliac crest to output forces and moments in the XYZ directions.

[0101] The DYNA keyword is *DATABASE_CROSS_SECTION.

[0102] The biomechanical data output settings of the human finite element model include:

[0103] Cortical bone strain data of key bones (skull, cervical vertebrae, thoracic vertebrae, lumbar vertebrae, ribs, sternum, pelvis, femur, tibia, and fibula);

[0104] Strain data of ligaments at important joints (shoulder, hip, knee);

[0105] Stress data of important organs (brain tissue, heart, lungs, spleen, liver, large and small intestines);

[0106] The strain data mainly include the first principal strain and the effective plastic strain, and the stress data mainly refers to the Feng stress.

[0107] The DYNA keyword is *DATABASE_EXTENT_BINARY.

[0108] After completing the matching of the virtual slide test environment, input the standard frontal 50% overlapping moving progressive deformation barrier collision MPDB waveform, and perform the virtual computing test after setting the virtual computing test parameters, including: global computing time, minimum computing step size, global simulation animation output data and computing control card, etc., to complete the virtual computing test matrix.

[0109] After completing the virtual test calculation, the validity of the calculation results needs to be evaluated. The evaluation conditions are as follows:

[0110] The specified calculation time is completed normally; no abnormal unit distortion and instability occur during the calculation process; the hourglass energy accounts for less than 5%; the mass increase accounts for less than 5%. It should be noted that there is no restriction on the specific calculation process of this part, and the effectiveness of the calculation results can be evaluated.

[0111] The content of analyzing the calculation results in step S103 specifically includes extracting the output data to be analyzed, and performing analysis and evaluation based on different evaluation contents. In this embodiment, the data to be analyzed includes dynamic data, biomechanical data and motion animation data of the human finite element model, specifically including the following contents:

[0112] Kinetic data include:

[0113] X-direction and synthetic acceleration-time history curves and peak values ​​at the center of mass of the head and point H of the pelvis;

[0114] Time history curves and peak values ​​of axial force (Fz), lateral shear force (Fy), flexion moment (My) and lateral flexion moment (Mx) of the vertebral cross section of the cervical spine (C1-C7);

[0115] Peak values ​​of axial force (Fz) and flexion moment (My) in thoracic (T1-T12) and lumbar (L1-L5) vertebral sections;

[0116] Axial force Fz-time history curve and peak value at the iliac crest section.

[0117] Biomechanical data include:

[0118] Head: First principal strain MPS of skull cortical boneSK Peak, brain tissue pressure PRES BR , VonS stress of brain tissue BR Peak value;

[0119] Spine: First principal strain (MPS) of vertebral cortical bone in cervical, thoracic and lumbar spine CS , MPS TS and MPS LS ) peak value;

[0120] Chest and abdomen: effective plastic strain (EPPS) of sternum, ribs and pelvic cortical bones ST , EPPS RB and EPPS PL ) peak, VonS stress of the heart, lungs, spleen, liver, large and small intestines HE , VonS LU , VonS LI and VonS IN ) peak value;

[0121] Lower limbs: effective plastic strain (EPPS) of femur, tibia, and fibula cortical bones FE , EPPS TI and EPPS FI ) peak value; first principal strain (MPS) of knee ligament LG ) peak value.

[0122] The motion animation data includes front view, left and right side view, top view and left and right test 50% cross-sectional view, wherein the frame rate is not less than 1000fps.

[0123] In this embodiment, the collision safety evaluation process framework based on the human body finite element model mainly includes two parts: human body motion evaluation and human body injury evaluation. The human body motion evaluation refers to the evaluation of the interaction between the human body finite element model and the zero-gravity seat and restraint system to be tested when it moves in the virtual test calculation. The human body injury evaluation refers to the evaluation of the damage of the human body finite element model in the virtual test calculation based on dynamic data and biomechanical data.

[0124] like Figure 3 As shown, the step of analyzing the data to be analyzed and outputting the safety virtual test evaluation result based on human motion in step S103 includes:

[0125] Extracting abnormal contact between the shoulder strap of the seat belt and the neck in the motion animation data of the front view and the top view from the data to be analyzed, and abnormal peaks appear in the time history curves of the cervical lateral shear force Fy and the lateral bending moment Mx in the dynamic data, and outputting an evaluation result based on the "strangulation" phenomenon and deducting a preset score;

[0126] Abnormal contact between the seat belt and the abdomen in the animations of the left and right side perspectives and the front perspective in the motion animation data is extracted from the data to be analyzed, and an abnormal falling edge appears in the axial force Fz time history curve at the iliac crest section in the dynamic data, then the evaluation result based on the "diving" phenomenon and recorded as "poor" is output.

[0127] It should be noted that the "strangulation" phenomenon refers to the shoulder strap of the seat belt invading the neck of the human finite element model during movement, and the "diving" phenomenon refers to the waist belt of the seat belt invading the abdomen of the human finite element model. The evaluation results are graded by setting a specific weighted scoring method. If there is no "strangulation" phenomenon, continue to the next step of the evaluation. If there is a "strangulation" phenomenon, 5 points will be deducted from the total score; if there is no "diving" phenomenon, continue to the next step of the evaluation. If there is a "diving" phenomenon, it will be directly recorded as poor in the evaluation results. Thus, the evaluation results of the virtual test of safety based on human movement based on different weighted scores are given. There are no restrictions on the setting of specific scores and the settings of excellent, general, and good levels, and different classifications of results can be achieved.

[0128] In this embodiment, the human body injury evaluation includes two parts: dynamic data result evaluation and biomechanical data result evaluation; the dynamic data results mainly include the following three: HIC based on the calculation of the head synthetic acceleration 15 Peak value, neck injury data N calculated based on neck axial force Fz and flexion moment My ij The peak value and the lumbar injury data L calculated based on the lumbar axial force Fz and flexion moment My ij The biomechanical data result includes the pre-configured peak results of all the aforementioned biomechanical data. The step of outputting the safety virtual test evaluation result of human body injury after analyzing the data to be analyzed includes:

[0129] The dynamic data and biomechanical data in the data to be analyzed are extracted and the test evaluation results of different parts based on the finite element model of the human body are output through the following model:

[0130] Head: SCROE HEAD =0.3*SC(HIC 15 )+0.3*SC(MPS SK )+0.2*SC(PRES BR )+0.2*SC(VonS BR )

[0131] Spine: SCROE SPINE =0.2*SC(N ij )+0.3*SC(L ij )+0.15*SC(MPSCS )+0.15*SC(MPS TS )+

[0132] 0.2*SC(MPS LS )

[0133] - Torso: SCROE TORSO =0.2*SC(EPPS ST )+0.3*SC(EPPS RB )+0.2*SC(EPPS PL )+0.15*SC(VonS HE )+0.05*SC(VonS LU )+0.05*SC(VonS LI )+0.05*SC(VonS IN )

[0134] Legs: SCROE LEG =0.25*SC(EPPS FE )+0.25*SC(EPPS TI )+0.25*SC(EPPS FI )+0.25*SC(MPS LG )

[0135] The evaluation results of the body part test are input into the following formula to obtain the safety virtual test evaluation results of human body injury:

[0136] SCROE INJURY =0.3*SCROE HEAD +0.3*SCROE SPINE +0.2*SCROE TORSO +0.2*SCROE LEG .

[0137] For any single evaluation result mentioned above, the corresponding evaluation interval with upper and lower limits is used for scoring. If the result is below the lower limit, 100 points are given, if the result is between the upper and lower limits, 60 points are given, and if the result is above the upper limit, 0 points are given. At the same time, the total score of the virtual test is finally obtained by combining the human body injury evaluation and human body movement evaluation results. The score below 60 points is a poor grade, 60 to 75 points is a general grade, 75 to 90 points is a good grade, and above 90 points is an excellent grade. Finally, the specific zero-gravity seat collision safety evaluation based on the human finite element model is completed. It should be noted that this embodiment does not impose specific restrictions on this part of the content, and it is sufficient to implement classification according to different score standards.

[0138] This embodiment also proposes a zero-gravity seat collision safety virtual test evaluation system, which is applied to the above evaluation method, such as Figure 4As shown, the system 50 includes:

[0139] A construction module 501 is used to construct a finite element model of a zero-gravity seat to be tested and evaluated, and to build a virtual slide test environment based on the first constraint condition of the zero-gravity seat;

[0140] A first processing module 502 is used to generate a second constraint condition based on a human finite element model according to the first constraint condition in the virtual slide test environment, adjust the posture of the human finite element model through the second constraint condition and couple and match the virtual slide test environment to perform a virtual computing test;

[0141] The second processing module 503 is used to extract the data to be analyzed based on the dynamic data, biomechanical data and motion animation data of the human finite element model based on the virtual calculation test results, and output the safety virtual test evaluation results based on human motion and human injury after analyzing the data to be analyzed;

[0142] Among them, the first constraint condition includes the seat back angle Angle (BA) based on the angle between the line connecting the upper edge feature point of the seat back frame and the backrest rotation center and the vertical plane, the zero gravity seat cushion angle Angle (CA) based on the angle between the line connecting the front edge feature point of the seat cushion frame and the cushion rotation center and the horizontal plane, and the seat leg support angle Angle (LSA) based on the angle between the line connecting the lower edge feature point of the seat leg support frame and the leg support rotation center and the vertical plane; the second constraint includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle based on the human body finite element model.

[0143] This embodiment further provides an electronic device, the device comprising:

[0144] at least one processor;

[0145] And, a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to implement the aforementioned zero-gravity seat collision safety virtual test evaluation method.

[0146] The present invention proposes a virtual test and evaluation method, system and equipment for zero-gravity seat collision safety, including a method for quickly building a virtual test environment for a zero-gravity seat slide, which can define a standard restraint system for rapid follow-up adjustment, and also defines human body model posture angle constraints based on the characteristic angles of the seat. Combined with the posture adjustment software, it can efficiently complete the adjustment and coupling matching of the lying human body model. The virtual test results are comprehensively evaluated based on comprehensive dynamic data and biomechanical data, with full attention paid to the injuries to the occupant's head, spine, chest, abdomen and lower limbs during the collision. It should be pointed out that in addition to the zero-gravity seat collision safety evaluation, this method should be applicable to a wider range of virtual test scenarios based on human finite element models, which can significantly reduce the testing cost compared to traditional physical testing.

[0147] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or change made by a person skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A virtual test and evaluation method for zero-gravity seat collision safety, characterized in that: The evaluation method comprises the following steps: Construct a finite element model of the zero-gravity seat to be tested and evaluated, and build a virtual slide test environment based on the first constraint condition of the zero-gravity seat; In the virtual slide test environment, generating a second constraint condition based on a human finite element model according to the first constraint condition, adjusting the posture of the human finite element model through the second constraint condition and coupling and matching the virtual slide test environment to perform a virtual computing test; Based on the virtual calculation test results, extract the data to be analyzed based on the dynamic data, biomechanical data and motion animation data of the human finite element model, analyze the data to be analyzed and output the safety virtual test evaluation results based on human motion and human injury; Among them, the first constraint condition includes the seat back angle Angle (BA) based on the angle between the line connecting the upper edge feature point of the seat back frame and the backrest rotation center and the vertical plane, the zero gravity seat cushion angle Angle (CA) based on the angle between the line connecting the front edge feature point of the seat cushion frame and the cushion rotation center and the horizontal plane, and the seat leg support angle Angle (LSA) based on the angle between the line connecting the lower edge feature point of the seat leg support frame and the leg support rotation center and the vertical plane; the second constraint includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle based on the human body finite element model.

2. The evaluation method according to claim 1, characterized in that: The step of constructing a finite element model of the zero-gravity seat to be tested and evaluated further includes, when constructing the finite element model of the zero-gravity seat to be tested and evaluated, determining whether there is an auxiliary restraint system of the zero-gravity seat to be tested and evaluated, and if not, calling a pre-stored standard seat belt restraint system; Among them, the zero-gravity seat finite element model at least includes the zero-gravity seat model size and mass data based on the seat frame, seat cushion, backrest, headrest and leg support structure; the auxiliary restraint system at least includes a seat belt, a fixing device and a seat cushion airbag structure; the fixed point position of the standard seat belt restraint system is rapidly adjusted based on the spatial coordinate control parameters.

3. The evaluation method according to claim 2, characterized in that: The step of building a virtual slide test environment based on the first constraint condition of the zero-gravity seat also includes confirming that the zero-gravity seat in the zero-gravity seat finite element model matches the functional position of the auxiliary restraint system or the standard seat belt restraint system, wherein the functional position at least includes the seat H point, the seat cushion angle, the seat back angle, the seat leg support angle, the position of the seat belt D ring, the position of the seat belt buckle and the position of the seat belt anchor point; The safety belt D-ring is rigidly coupled to the zero-gravity seat back frame to be tested and evaluated, and the outer buckle of the safety belt buckle and the inner anchor point of the safety belt anchor point are rigidly coupled to the zero-gravity seat cushion frame.

4. The evaluation method according to claim 3, characterized in that: The step of generating a second constraint condition based on a human body finite element model according to the first constraint condition comprises inputting the first constraint condition into the following formula to generate a second constraint condition: The target pelvic angle is expressed as the angle between the pelvis and the vertical plane: Angle(Pelvis)=55.5+0.33*Angle(BA); The torso angle is expressed as the angle between the shoulder-H point line and the vertical plane: Angle (Torso) = -7.5 + 0.86 * Angle (BA); The lumbar angle is expressed as the angle between the lumbar spine and the vertical plane: Angle (Lumbar) = 2.3 + 0.59 * Angle (BA); The thigh angle is expressed as the angle between the thigh and the horizontal plane: Angle (Thigh) = 9.5 + Angle (CA); The shank angle is expressed as the angle between the shank and the horizontal plane: Angle(Leg)=9.5+Angle(LSA).

5. The evaluation method according to claim 4, characterized in that: The steps of adjusting the posture of the human finite element model by the second constraint condition and coupling and matching the virtual slide test environment to perform a virtual computing test include: Decomposing each angle in the second constraint condition to generate a hinge angle corresponding to the human finite element model, so as to transform the standard human finite element posture of the initial upright posture into a customized target lying posture, and coupling it with the zero-gravity seat finite element model; after completing the matching of the corresponding H-point position, forming a natural indentation on the seat and cushion backrest of the zero-gravity seat, and completing the matching of the seat belt; After completing the matching of the virtual slide test environment, input the standard frontal 50% overlapping moving progressive deformation barrier collision MPDB waveform, and perform the virtual calculation test after setting the virtual calculation test parameters.

6. The evaluation method according to claim 5, characterized in that: Extracting the dynamics data, biomechanical data and dynamics data from the finite element model of the human body includes: X-direction and synthetic acceleration-time history curves and peak values ​​at the center of mass of the head and point H of the pelvis; The time history curves and peak values ​​of the axial force Fz, lateral shear force Fy, flexion moment My and lateral flexion moment Mx of the cervical vertebral body section; The peak values ​​of the axial force Fz and the flexion moment My of the thoracic and lumbar vertebral sections; Axial force Fz-time history curve and peak value at the iliac crest section; The biomechanical data include: Head: First principal strain MPS of skull cortical bone SK Peak, brain tissue pressure PRES BR , VonS stress of brain tissue BR Peak value; Spine: First principal strain MPS of vertebral cortical bone in cervical, thoracic and lumbar spine CS , MPS TS and MPS LS Peak value; Chest and abdomen: effective plastic strain EPPS of sternum, ribs and pelvic cortical bones ST , EPPS RB and EPPS PL Peak value, VonS stress of heart, lung, spleen, liver, large and small intestine HE , VonS LU , VonS LI and VonS IN Peak value; Lower limbs: effective plastic strain EPPS of femur, tibia, and fibula cortical bones FE , EPPS TI and EPPS FI Peak value; first principal strain MPS of knee ligament LG Peak value; The motion animation data includes pictures of front viewing angle, left and right side viewing angles, top viewing angle and left and right test 50% cross-sectional viewing angles, wherein the frame rate is not less than 1000fps.

7. The evaluation method according to claim 6, characterized in that: The step of analyzing the data to be analyzed and outputting the safety virtual test evaluation result based on human motion comprises: Extract from the data to be analyzed the abnormal contact between the shoulder strap of the safety belt and the neck in the motion animation data of the front view and the top view, and the abnormal peak value of the time history curve of the cervical lateral shear force Fy and the lateral bending moment Mx in the dynamic data, and output the evaluation result based on the "strangulation" phenomenon and deducting the preset score; Abnormal contact between the seat belt and the abdomen in the animations of the left and right side perspectives and the front perspective in the motion animation data is extracted from the data to be analyzed, and an abnormal falling edge appears in the axial force Fz time history curve at the iliac crest section in the dynamic data, then the evaluation result based on the "diving" phenomenon and recorded as "poor" is output.

8. The evaluation method according to claim 6, characterized in that: The step of outputting the safety virtual test evaluation result of human body injury after analyzing the data to be analyzed comprises: The dynamic data and biomechanical data in the data to be analyzed are extracted and the test evaluation results of different parts based on the finite element model of the human body are output through the following model: Head: SCROE HEAD =0.3*SC(HIC 15 )+0.3*SC(MPS SK )+0.2*SC(PRES BR )+0.2*SC(VonS BR ) Spine: SCROE SPINE =0.2*SC(N ij )+0.3*SC(L ij )+0.15*SC(MPS CS )+0.15*SC(MPS TS )+ 0.2*SC(MPS LS ) Trunk: SCROE TORSO = 0.2 * SC(EPPS ST ) + 0.3 * SC(EPPS RB ) + 0.2 * SC(EPPS PL ) + 0.15 * SC(VonS HE ) + 0.05 * SC(VonS LU ) + 0.05 * SC(VonS LI ) + 0.05 * SC(VonS IN ) Legs: SCROE LEG =0.25*SC(EPPS FE )+0.25*SC(EPPS TI )+0.25*SC(EPPS FI )+0.25*SC(MPS LG ) Input the evaluation results of the sub-part test into the following formula to obtain the safety virtual test evaluation results of human body injury: SCROE INJURY =0.3*SCROE HEAD +0.3*SCROE SPINE +0.2*SCROE TORSO +0.2*SCROE LEG 。 9. Zero-gravity seat collision safety virtual test and evaluation system, characterized in that: The evaluation system is applied to the evaluation method according to any one of claims 1 to 8, and the system comprises: A construction module is used to construct a finite element model of a zero-gravity seat to be tested and evaluated, and to build a virtual slide test environment based on the first constraint condition of the zero-gravity seat; A first processing module is used to generate a second constraint condition based on a human finite element model according to the first constraint condition in the virtual slide test environment, adjust the posture of the human finite element model through the second constraint condition and couple and match the virtual slide test environment to perform a virtual computing test; A second processing module is used to extract the data to be analyzed based on the dynamic data, biomechanical data and motion animation data of the human finite element model based on the virtual calculation test results, and output the safety virtual test evaluation results based on human motion and human injury after analyzing the data to be analyzed; Among them, the first constraint condition includes the seat back angle Angle (BA) based on the angle between the line connecting the upper edge feature point of the seat back frame and the backrest rotation center and the vertical plane, the zero gravity seat cushion angle Angle (CA) based on the angle between the line connecting the front edge feature point of the seat cushion frame and the cushion rotation center and the horizontal plane, and the seat leg support angle Angle (LSA) based on the angle between the line connecting the lower edge feature point of the seat leg support frame and the leg support rotation center and the vertical plane; the second constraint includes the target pelvic angle, trunk angle, lumbar angle, thigh angle and calf angle based on the human body finite element model.

10. An electronic device, characterized in that: The device comprises: at least one processor; And, a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to implement the zero-gravity seat collision safety virtual test evaluation method as described in any one of claims 1-8.

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