Automobile digital evaluation model with Chinese 95 percent male sign passenger posture, model construction method and application

Abstract

The invention discloses an automobile digital evaluation model with 95th percentile male signs of Chinese signs, which performs analog simulation on human tissues through various finite element grid units, endows different material attributes, optimizes detailed human anatomical structural characteristics, splices different tissue structures, and improves the evaluation accuracy. And obtaining the model. The invention further discloses a construction method of the model, which comprises the following steps of: constructing a human body geometric model by collecting CT data of signs of 95th percent male in China, forming hexahedral unit structures such as heart and sacrum through finite element mesh division, correcting physiological curvature of the spine, constructing tissues such as intervertebral disc and fibrous ring, forming a standing posture model through tendon connection, and constructing a human body model. According to the sitting posture angle of the passenger, the posture is adjusted, muscle grids are optimized, and finally, all tissue structures are integrated to form the passenger posture automobile digital evaluation model with the signs of the 95th percentile male in China. The method has wide application value.

Description

Technical Field

[0001] The present invention belongs to the technical fields of human numerical calculation model development, automotive safety technology research and development, collision testing, and safety system optimization. It relates to a digital evaluation model for the occupant posture of a vehicle with the physical characteristics of the 95th percentile male in China, a model construction method, and an application thereof. Background Art

[0002] The research on the injury mechanism of vehicle occupants in the field of vehicle collision safety can be divided into several typical methods, such as cadaver tests, volunteer tests, Anthropometric Test Devices (ATDs), and digital human models. Cadaver tests and volunteer tests are restricted by difficulties in obtaining samples and ethical issues, and there are few publicly available references. Currently, research on human injuries in vehicle collisions mainly relies on ATDs and digital human models. An ATD is a physical dummy, usually made of plastic and metal materials, which simulates the shape and movement of the human body to evaluate the safety and potential injuries of occupants in collision tests. Relatively speaking, a digital human model is a virtual model generated by a computer. Based on anatomical data and biomechanical principles, it can better simulate the forces and deformations of the human body during a collision. The test results of ATDs are relatively intuitive, but due to the limitations of the model settings and materials, they cannot fully reflect the influence of different body sizes or weights on the test results. A digital human model can adjust parameters to generate virtual models of various body sizes for simulation calculations, which not only improves the flexibility of model use but also reduces experimental costs.

[0003] There are two types of digital human models. One is the multi-rigid body model, which can calculate the kinematic response of the human body model in a relatively short CPU time. The other is the finite element human model. Compared with the above models, the finite element human model can more accurately describe the anatomical structure of the human body, such as soft tissues like bones, internal organs, and muscles, and can effectively evaluate the human collision response and local variables related to injuries. For example, the finite element model can predict complex chest deformations and fractures.

[0004] At present, multiple versions of human finite element models have been developed abroad. However, most of these models are scaled based on the 50th percentile male model, and these human models are designed and developed based on the body size standards of Europe and the United States. There are significant differences between the body sizes of Chinese people and those of Europe and the United States. Therefore, it is not accurate to use human models based on European and American standards to evaluate the injury risks of Chinese occupants in vehicle collisions. In addition, the new car assessment programs (NCAP) of various countries mainly select the 50th percentile male occupants of medium build and the 5th percentile female occupants of small build as test subjects, but ignore the test situation of the 95th percentile male occupants of large build. Given the diversity of modern population body types, the limitations of this testing method have become increasingly obvious, especially in evaluating the collision risks that large-build occupants may face. In order to more comprehensively evaluate the injuries of occupants in vehicle collisions, it is necessary to develop diverse finite element models. These models should comprehensively consider the differences in different genders and body types. Therefore, a bionic model of a 95th percentile male vehicle occupant injury that conforms to Chinese physical characteristics is developed based on the CT images of 95th percentile male volunteers, so as to conduct research on the injury mechanism of large-build male occupants. Summary of the Invention

[0005] In order to solve the deficiencies of the existing technology, the purpose of the present invention is to provide a digital evaluation model (also known as a biomechanical model), a model construction method and an application with the physical characteristics of the 95th percentile male in China.

[0006] The present invention provides an occupant posture digital evaluation model for a vehicle with the physical characteristics of the 95th percentile Chinese male, also known as a biomechanical model, which is a digital calculation tool in the field of vehicle crash safety. The digital evaluation model or biomechanical model of the present invention conforms to the physical characteristic parameters of the 95th percentile Chinese male in the latest human body size statistical data of the China National Institute of Standardization. The model has a weight of 85.3 kg, a sitting height of 99.9 cm, a shoulder width of 41.5 cm, a maximum shoulder width of 49.4 cm, a chest thickness of 25.6 cm, a chest width of 31.8 cm, 1.536 million elements, and 1.203 million nodes. The model has detailed human anatomical structure characteristics, including structures such as bones, muscles, internal organs, fat, soft tissues, ligaments, tendons, and skin. The model uses hexahedral elements, quadrilateral shell elements, a small number of pentahedral elements, and / or triangular shell elements for simulation according to different structures and parts of the human body. Specifically, cancellous bone, muscles, internal organs, fat, and soft tissues of the bones use hexahedral elements; cortical bone, ligaments, joint capsules, muscle fascia, internal organ membranes, and skin of the bones use quadrilateral shell elements; some ligaments and tendons use pentahedral elements and triangular shell elements; the various tissue structures are connected in a co - nodal manner. The tissue structures in the model are given corresponding material properties according to their different mechanical properties, and contacts are defined based on the tissue structure relationship. Specifically, the *CONTACT_AUTOMATIC_SINGLE_SURFACE keyword is selected to define the self - contact between the various tissue structures of the model, the *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE keyword is selected to define the contact between joints in the model, and the DATABASE_CROSS_SECTION_PLANE keyword is selected to define the cross - section of the spinal finite element model.

[0007] The present invention has particularly optimized the construction of the heart, sacrum, and hip bone structures. A hexahedral element is used to construct a heart structure including the left atrium, right atrium, left ventricle, right ventricle, pulmonary artery, aorta, superior vena cava, and inferior vena cava structures; a sacrum structure including the sacral canal, anterior sacral foramina, and posterior sacral foramina structures; and a hip bone structure including the acetabular fossa, obturator foramen, pubic tubercle, ischial tuberosity, iliac body, and iliac wing.

[0008] The model in the present invention has a high degree of biological simulation and can be used to carry out research on the crash biomechanics of large - sized male vehicle occupants. The content of the present invention is applicable to multiple fields such as medicine, engineering, sports science, product design, and emergency rescue.

[0009] The present invention proposes a method for constructing an occupant posture digital evaluation model for a vehicle with the physical characteristics of the 95th percentile Chinese male with detailed anatomical structures. The specific steps of the construction method are as follows:

[0010] Step A: According to the latest measured physical sign statistical data of the China National Institute of Standardization, obtain the CT image data of volunteers who meet the physical signs of Chinese men at the 95th percentile multiple times. Based on the CT data, reconstruct the human geometric model, including bones, muscles, internal organs, soft tissues, and skin, etc.; the human geometric model can be divided into a rectangular geometric model, a trapezoidal geometric model, and a columnar geometric model according to its shape;

[0011] Step B: Perform finite element mesh division on the geometric model obtained in Step A to construct finite element models of various organizational structures, including finite element models of the heart, sacrum, hip bone, spinal column, etc.;

[0012] In particular, for the heart structure in the model, use hexahedral finite element meshes (hexahedral elements) to construct structures including the left atrium, right atrium, left ventricle, right ventricle, pulmonary artery, aorta, superior vena cava, and inferior vena cava, etc.; for the sacrum structure in the model, use hexahedral finite element meshes to construct structures including the sacral canal, anterior sacral foramina, and posterior sacral foramina, etc.; for the hip bone structure in the model, use hexahedral finite element meshes to construct structures including the acetabular fossa, obturator foramen, pubic tubercle, ischial tuberosity, iliac body, and iliac wing, etc.; for the spinal column structure in the model, use hexahedral finite element meshes to construct structures including vertebral bones, intervertebral discs (nucleus pulposus, annulus fibrosus), spinal cord, etc., and use quadrilateral shell elements to construct ligaments (ligamenta flava, anterior longitudinal ligament, posterior longitudinal ligament, interspinous ligament, supraspinous ligament), etc.

[0013] Step C: For the spinal column finite element model constructed in Step B, correct the spinal column physiological curvature according to the normal spinal column physiological curvature of human anatomy, and construct the intervertebral disc, nucleus pulposus, annulus fibrosus, and ligaments; use the "Move" command to select the nodes of the annulus fibrosus at different positions of the spinal column on the hexahedral mesh and move them along the offset direction of the node perimeter at a certain distance to simulate the arc structure of the outer surface of the annulus fibrosus; specifically, the average offset distance of the annulus fibrosus in the cervical spine part is 0.6 - 0.8 mm; the average offset distance of the annulus fibrosus in the thoracic spine part is 0.8 - 1.0 mm; the average offset distance of the annulus fibrosus in the lumbar spine part is 1.0 - 1.2 mm;

[0014] Step D: Connect the finite element models of various organizational structures constructed in Step B and the spinal column finite element model with the adjusted physiological curvature constructed in Step C by means of tendons and ligaments to form a finite element model of a Chinese male standing posture at the 95th percentile of physical signs;

[0015] Step E: Adjust the standing posture finite element model obtained in Step D to the occupant posture according to the normal sitting posture angle range of the occupant, and reversely optimize and adjust the muscle mesh division;

[0016] Step F: Connect the organizational structures of each part of the finite element model of a male car with the 95th percentile of Chinese physical characteristics that has been adjusted to the occupant's posture, and finally obtain a digital evaluation model of the occupant posture car with the physical characteristics of a male with the 95th percentile of Chinese physical characteristics.

[0017] In the present invention, the reconstruction of the human geometric model in the said Step A includes the following sub-steps:

[0018] Step A1: In Mimics software, geometrically extract each organizational structure including bones, fat, skin, internal organs, muscles, etc. with different gray value ranges, and generate a 3D model;

[0019] Specifically, in Mimics software, geometrically extract bones, fat, skin, muscles, and internal organs, etc. according to different gray value ranges, and generate a 3D model. Specifically, the gray value range of bones is [148, 661], fat is [-51, 205], skin is [-718, -177], muscles are [-5, 135], and internal organs are [-178, 146];

[0020] Step A2: For the generated 3D model, in Mimics software, define the smoothing coefficient as 0.6 using the "Smooth" instruction, define the tolerance as 1 mm using the "Reduce" instruction, define the edge angle as 10°, and define the gap closing distance as 5 mm using the "Wrap" instruction. By performing "Smooth", "Reduce", and "Wrap" definition processing on the surface of the geometric model, the error generated by the geometric model on the finite element model can be significantly reduced, the accuracy and reliability of the overall model can be improved, and it is output in the *.STL file format;

[0021] Step A3: Import the *.STL file obtained in Step A2 into Geomagic software, and perform operations on the geometric model including refinement, fast smoothing, relaxation, removing spikes, removing features, etc.; process the concave and convex parts of the edge of the geometric model through patching and trimming; use the "Bridge" instruction under the "Fill Hole" module to repair the holes to make it conform to the human anatomical structure; in order to effectively reduce the error generated during the mutual penetration of geometric models, perform Boolean operations on two adjacent geometric models to optimize their geometric shapes; divide the surface patches of the geometric model that has been smoothed according to its shape and construct a grid, and finally fit it into a NURBS surface and convert it into a CAD model, and output it in the *.SAT file format.

[0022] In the present invention, the finite element mesh generation method in the said Step B includes the following sub-steps:

[0023] Step B1: Import the processed geometric model in step A into ANSA software in the *.SAT format;

[0024] Step B2: For the rectangular geometric model, adopt the "Hexahedral-box" method, that is, in the "HEXA BLOCK" module, use the "Boxes" instruction to create a "Box" for the whole geometric model, divide the "Box" according to the distribution position of the surface patches, move the nodes on the "Box" to the intersection points of the contour lines on the surface patches, and then perform point-to-point and line-to-line fitting;

[0025] and / or,

[0026] For the trapezoidal geometric model, adopt the "Hexahedral-box-box" method, that is, segment the geometric model to create "Boxes" according to the surface patches, and perform "face-to-face" fitting on the corresponding faces of two adjacent "Boxes" through the "Paste" command to make the "Boxes" share edges;

[0027] and / or,

[0028] For the columnar geometric model, adopt the "O-Grid structure", that is, the "butterfly grid", and select the box face that has been fitted with the "Box" to perform an inward offset through the "O-Grid" command to construct an orthogonal structure (butterfly structure);

[0029] Step B3: To ensure high-quality finite element meshes, adopt the "layered mesh" method, and increase the internal mesh density of the geometric model by evenly dividing the length, width, and height regions of the "Box" that has been fitted to constrain the internal mesh distribution;

[0030] Step B4: According to the mesh size requirements, set the number of meshes for the edges of the "Box" that has been fitted through the "Number" command; in a specific embodiment, the mesh size requirements are that the maximum element size does not exceed 12 mm and the minimum element size does not exceed 1 mm, and the size will be adjusted according to the actual situation to make it more in line with the actual needs;

[0031] Step B5: Through the "Volume Mesh" instruction, perform pure hexahedral mesh division on the entire fitted "Box", and reduce the uneven distribution of internal meshes by smoothing the constructed hexahedral meshes to complete the hexahedral mesh division of the geometric model.

[0032] In the present invention, the spine physiological curvature correction and construction in step C include the following sub-steps:

[0033] Step C1: According to the normal spinal physiological curvature image, use the point - plotting method to take points on the upper, middle, and lower regions of the front surfaces of 24 vertebral bodies and the upper surface of the front end of the sacrum along the median sagittal plane of the human body, and connect the 73 selected points with a spline curve to obtain the normal spinal physiological curvature curve;

[0034] Step C2: Import the obtained normal spinal physiological curvature curve into ANSA software and scale it so that the spinal physiological curvature curve is the same size as the spinal finite - element model;

[0035] Step C3: Taking the sacrum as a reference, fit the terminal sacral point of the normal spinal physiological curvature curve to the sacrum, and then translate and rotate each vertebral body individually to make it fit the points on the curve, finally obtaining the spinal physiological curvature of the 95th percentile male with Chinese physical characteristics;

[0036] Step C4: Through the "Elements" instruction under the "MESH" module, complete the construction of the intervertebral disc between every two adjacent upper and lower vertebral bodies; use the "Solid Builder" command to construct the annulus fibrosus with the lower surface of the upper vertebral body and the upper surface of the lower vertebral body as boundaries around the edge of the already constructed intervertebral disc, and then move the nodes on the finite - element mesh of the annulus fibrosus through the "Move" command to simulate the arc - shaped structure of the outer surface of the annulus fibrosus;

[0037] Step C5: Simulate the structures such as the zygapophyseal joint capsule, articular cartilage, interspinous ligament, supraspinous ligament, transverse ligament, ligamentum flavum, anterior longitudinal ligament, and posterior longitudinal ligament between vertebral bodies by constructing quadrilateral meshes to obtain a spinal finite - element model of the 95th percentile male that conforms to the normal physiological curvature.

[0038] In the present invention, the construction of the finite - element model of the standing posture of the 95th percentile male with Chinese physical characteristics in step D includes the following sub - steps:

[0039] Step D1: Taking the finite - element model of the head as a reference, connect the spinal finite - element model after calibration and construction in step C with the finite - element model of the head;

[0040] Step D2: Adjust and connect the finite - element model of the ribs according to the human anatomical structure, and simulate the connection parts between muscles and bones through 2D shell elements and pentahedrons;

[0041] Step D3: Symmetrize the finite - element models of the upper and lower limbs according to the median sagittal plane of the human body and connect them to the corresponding bones through ligaments and tendons;

[0042] Step D4: Import the smoothed skin geometric model into ANSA software, construct the fat through "Projection", and finally obtain the finite element model of the 95th percentile male standing posture with Chinese physical characteristics. The specific operation of "Projection" is as follows: Use the "Extrude" command to select the area to be projected, then select the skin structure as the boundary condition, and finally project the fat by combining the "Offset" and "Guidelines" instructions.

[0043] In the present invention, the adjustment of the sitting posture of the 95th percentile male occupant with Chinese characteristics in step E includes the following sub-steps:

[0044] Step E1: Take the pelvic structure, namely bones such as the sacrum, hip bone, and coccyx as the reference, and adjust the finite element model of the 95th percentile male standing posture to the occupant posture;

[0045] Step E2: Adjust the body angle of the finite element model of the 95th percentile male according to the normal sitting posture angle range of the occupant; Specifically, adjust the corresponding upper arm angle, forearm angle, backrest angle, trunk angle, knee angle, and ankle angle according to the rotation centers of the shoulder joint, elbow joint, wrist joint, hip joint, knee joint, and ankle joint; The normal sitting posture range includes: upper arm angle 0° - 30°, forearm angle 120° - 160°, backrest angle 20° - 30°, angle between the trunk and the thigh 95° - 115°, knee angle 100° - 145°, ankle angle 87° - 110°;

[0046] Step E3: Calibrate and connect the finite element model of the muscles in the sitting posture; For muscle structures with relatively large deformation amounts, such as the gluteus maximus, rectus femoris, long head of the biceps femoris, lateral head of the gastrocnemius, and medial head of the gastrocnemius, in order to ensure the quality of the finite element mesh, use the reverse engineering method: Generate shell elements on the surface of the deformed structure and output it in the *.STL file format, import it into Geomagic software to re-divide the surface patches, and finally import it into ANSA software to re-divide the mesh.

[0047] In step F, connect the finite element model adjusted to the occupant posture in step E, mainly including structures such as tendons, ligaments, fat, and skin at the shoulder joint, elbow joint, hip joint, and knee joint, and finally obtain the digital evaluation model of the car with the physical characteristics of the 95th percentile male with Chinese physical characteristics.

[0048] The present invention also provides a digital evaluation model of an automobile with the physical characteristics of the 95th percentile Chinese male constructed based on the above method. The characteristic dimensions of the model conform to the human body dimension statistical data of the China National Institute of Standardization. The weight of the model is 85.3 kg, the sitting height is 99.9 cm, the shoulder width is 41.5 cm, the maximum shoulder width is 49.4 cm, the chest thickness is 25.6 cm, the chest width is 31.8 cm, the number of elements is 1.536 million, and the number of nodes is 1.203 million. The model has a detailed anatomical structure. For different tissue structures, corresponding material properties are assigned to endow the model with mechanical properties.

[0049] Among them, for the digital evaluation model, the *CONTACT_AUTOMATIC_SINGLE_SURFACE keyword is selected to define the self-contact between the organizational structures of the model, the *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE keyword is selected to define the contact between joints in the model, and the DATABASE_CROSS_SECTION_PLANE keyword is selected to define the cross-section of the spinal finite element model.

[0050] Among them, the local parts (head, neck, upper limbs, lower limbs, pelvis) and the whole-body verification test of the digital evaluation model can effectively reflect biomechanical characteristics and can effectively reflect the conditions of fractures, craniocerebral injuries, and visceral injuries. The digital evaluation model can be applied to the evaluation of occupant protection in automobile crash safety performance tests and new car assessment procedures, filling the gap in the injury evaluation of large-sized male occupants in the evaluation.

[0051] Among them, the digital evaluation model is also applicable to multiple fields such as medicine, engineering, sports science, product design, and emergency rescue, specifically including automobile design and safety research, road traffic accident research, medical research and medical device design, and emergency rescue implementation, etc. By simulating the natural response mechanism of organisms to injuries, the model provides an in-depth understanding of the injury mechanism, and then provides innovative solutions for various application fields. Specifically, in the medical field, the model can be used to guide the research and development of new treatment plans and improve the rehabilitation effect of patients. In the engineering field, design methods based on human adaptability can develop more robust and safe materials and structures. In sports science, the model helps athletes formulate personalized training plans and reduce the risk of injury. In product design, the model promotes the development of more ergonomic products. In the emergency rescue field, it simulates the reactions of organisms in emergencies, optimizes rescue strategies, and improves rescue efficiency. Through interdisciplinary cooperation and innovation, the model can improve the quality of life and safety level of humans.

[0052] The beneficial effects of the present invention include: The construction of a digital evaluation model for automobiles with the physical characteristics of the 95th percentile male in China proposed by the present invention fills the gap in the construction of the finite element model of the 95th percentile male occupants in the country. Compared with the digital models developed abroad, the anatomical characteristics are more obvious and the bio - simulation degree is higher. It can more accurately judge different stress and strain of the human body and its damage conditions, and can provide basic data and technical support for automotive digital evaluation technology, the integrated research of automotive active and passive safety, and the research and development of safety protection devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0054] Figure 1 It is a flowchart of the construction method and application of the digital evaluation model for automobiles with the physical characteristics of the 95th percentile male in China of the present invention.

[0055] Figure 2 It is a schematic diagram of Boolean operation of geometric models; among them, (a) is the original geometric model, (b) is the geometric model after Boolean operation, and (c) is the geometric model after smoothing treatment.

[0056] Figure 3 It is a schematic diagram of hexahedral finite element mesh division of a trapezoidal geometric model using the "Hexahedral - box - box" method; among them, (a) is the geometric model with contour lines after processing, (b) is the "Box" constructed by segmenting according to the outer contour of the geometric model, (c) is the surface - to - surface fitting of two "Boxes", (d) is the fitted "Box", (e) is the number of meshes set for each side of the "Box", and (f) is the hexahedral finite element mesh.

[0057] Figure 4 It is a schematic diagram of the "layered mesh" method for improving the quality of finite element meshes; among them, (a) is the geometric model with the "Box" already fitted, (b) is the internal mesh distribution of the finite element without using the "layered mesh" method, (c) is the uniform division of adjacent sides of the "Box", (d) is the internal node distribution, and (e) is the internal mesh distribution of the finite element using the "layered mesh" method.

[0058] Figure 5 It is a schematic diagram of the correction of the physiological curvature of the spine; among them, (a) is the physiological curvature of the spine before correction, (b) is the normal physiological curvature curve of the spine of the 95th percentile male in China, and (c) is the physiological curvature of the spine after correction.

[0059] Figure 6 It is a schematic diagram of a hexahedral heart structure. The heart structure includes: left atrium, right atrium, left ventricle, right ventricle, pulmonary artery, aorta, superior vena cava, and inferior vena cava.

[0060] Figure 7 It is a schematic diagram of a hexahedral pelvis structure; among them, (a) is the sacral structure, (b) is the hip bone structure, and (c) is the cross-sectional view of the sacrum.

[0061] Figure 8 It is for determining the rotation axes of various parts of the occupant's body for attitude adjustment; among them, (a) is the rotation axis of the upper body trunk, (b) is the rotation axis of the lower limbs, (c) is the rotation axis of the lower leg, (d) is the rotation axis of the foot, (e) is the rotation axis of the upper limb, and (f) is the rotation axis of the elbow joint.

[0062] Figure 9 It is a schematic diagram of muscle shape correction; among them, (a) is the finite element model before correction, (b) is to construct a "Box" for the deformed area, (c) is the finite element model after deformation, (d) is the new geometric model after reverse operation, (e) is the surface patch division of the new geometric model, and (f) is the finite element model after correction.

[0063] Figure 10 It is a schematic diagram of the automotive digital evaluation model of the 95th percentile male physical signs in China according to the present invention; among them, (a) is the front view and (b) is the side view.

[0064] Figure 11 It is a schematic diagram of the cooperation between the automotive digital evaluation model of the 95th percentile male physical signs in China according to the embodiment of the present invention and the seat.

[0065] Figure 12 It is a schematic diagram of the accelerations of various parts of the body of the automotive digital evaluation model of the 95th percentile male physical signs in China according to the embodiment of the present invention; among them, (a) is the head acceleration, (b) is the acceleration of thoracic vertebra T1, (c) is the acceleration of thoracic vertebra T8, and (d) is the pelvic acceleration. Detailed implementation manners

[0066] Combined with the following specific embodiments and drawings, the present invention will be further described in detail. The processes, conditions, experimental methods, etc. for implementing the present invention, except for the specifically mentioned content below, are all common knowledge and well-known common sense in the art, and the present invention has no particularly restricted content.

[0067] The digital evaluation model of a vehicle (also known as the biomechanical model) for the 95th percentile male physical characteristics in China proposed in the present invention is constructed based on the CT medical image data of male volunteers at the 95th percentile in the Chinese population. The characteristic dimensions of the model conform to the human body dimension statistical data of the China National Institute of Standardization. The weight of the model is 85.3 kg, the sitting height is 99.9 cm, the shoulder width is 41.5 cm, the maximum shoulder width is 49.4 cm, the chest thickness is 25.6 cm, the chest width is 31.8 cm, the number of elements is 1.536 million, and the number of nodes is 1.203 million. The model has a detailed anatomical structure, including structures such as bones, muscles, internal organs, fat, soft tissues, ligaments, tendons, and skin. The model uses hexahedron elements, quadrilateral shell elements, as well as a small number of pentahedron elements and triangular shell elements for simulation, and the various tissue structures are connected in a co - nodal manner. The tissue structures in the model are given corresponding material properties according to their different mechanical properties.

[0068] The digital evaluation model described in the present invention has a high degree of biological simulation and can be used to carry out research on the biomechanics of vehicle occupant collisions for the 95th percentile male physical characteristics in China. The digital evaluation model of a vehicle with the 95th percentile male physical characteristics in China proposed in the present invention fills the domestic research gap on the injury mechanism of large - sized male occupants and can be used for the integrated research of vehicle passive and active safety as well as vehicle digital evaluation, etc.

[0069] The present invention provides a method for constructing the above - mentioned digital evaluation model, as Figure 1 shown, which includes the following steps:

[0070] (1) Geometric model reconstruction method.

[0071] According to the latest measured physical characteristic statistical data of the China National Institute of Standardization, obtain the CT image data of volunteers conforming to the 95th percentile male physical characteristics in China in multiple times, and accurately extract the human geometric model, including bones, muscles, internal organs, soft tissues, and skin, etc., using Mimics software. Define the smoothing coefficient, tolerance, edge angle, and gap closing distance using the "Smooth", "Reduce", and "Wrap" commands to pre - process the surface of the accurately extracted geometric model. This pre - processing step aims to significantly reduce the error generated by the geometric model on the finite element model and improve the accuracy and reliability of the overall model. By reasonably setting the above - mentioned parameters, the present invention can optimize the smoothness of the geometric surface and ensure better performance and accuracy of the model in subsequent analysis and applications.

[0072] Import the geometric model into Geomagic software. In the polygon stage, perform surface smoothing of the geometric model through commands such as refinement, fast smoothing, relaxation, removing spikes, and feature removal. To ensure that the edge curvature of the geometric model better conforms to the true anatomical structure, repair and trim the concave and convex parts of the edges: delete the mesh of the selected area, and use "Curvature" and "Bridge" in the "Fill Hole" command to select and delete the surrounding mesh of the selected area, so that the curvature of the newly generated mesh matches the curvature of the surrounding mesh. To effectively reduce the errors generated during the mutual penetration of geometric models, perform a Boolean operation on two adjacent geometric models to optimize their geometric shapes. Specifically, first select two adjacent geometric models, as shown in Figure 2 (a), and perform a subtraction operation to eliminate geometric errors caused by model overlap, while ensuring that the original object remains unchanged and is available for subsequent processing. After the subtraction, the newly generated geometric model is as shown in Figure 2 (b), with an uneven surface and abnormal mesh curvature, and needs to be further processed in the polygon stage. Perform a surface smoothing operation to improve the overall geometric quality. The processed geometric model is as shown in Figure 2 (c); in the precise surface stage, first, create preliminary surface patches on the geometric model using the drawing command; then, adjust the shapes of these surface patches through the relaxation command to achieve the required smoothness and continuity. On this basis, use the split / merge command to process complex geometric structures to make the connections between surface patches more reasonable. In addition, subdividing the curves helps increase the resolution of the surface patches, thereby enhancing the surface detail performance. Finally, optimize the constructed grid through commands such as contraction to ensure the precise fitting of the surface. The finally generated surface data is fitted into a NURBS (Non-Uniform Rational B-Spline) surface, ensuring the high controllability and flexibility of the surface through this standardized format. Finally, convert the generated surface into a CAD model and output it in the *.SAT file format.

[0073] (2) Finite element model construction method.

[0074] The reconstructed human body geometric model can be divided into a rectangular geometric model, a trapezoidal geometric model, and a columnar geometric model according to its shape. Specifically, the rectangular geometric model includes ribs, costal cartilages, collarbones, upper and lower jaws, trapezium, trapezoid, capitate, hamate, pisiform, triquetral, lunate, scaphoid, metacarpals, proximal phalanges, middle phalanges, distal phalanges, medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid, navicular bone, talus, calcaneus, patella, heart, liver, spleen, pancreas, kidneys, stomach, large intestine, small intestine, bladder, prostate, trachea, esophagus, blood vessels; the trapezoidal geometric model includes the sternum, scapula, sacrum, hip bone, cervical vertebrae (C1-C7), thoracic vertebrae (T1-T12), lumbar vertebrae (L1-L5); the columnar geometric model includes the humerus, ulna, radius, femur, tibia, fibula, lungs. Muscles in different parts can be classified into the above three types.

[0075] In the present invention, particularly for the heart structure in the model, a hexahedral finite element mesh (hexahedral elements) is used to construct structures including the left atrium, right atrium, left ventricle, right ventricle, pulmonary artery, aorta, superior vena cava, and inferior vena cava, as Figure 6 shown; for the sacral structure in the model, a hexahedral finite element mesh is used to construct structures including the sacral canal, anterior sacral foramina, and posterior sacral foramina; for the hip bone structure in the model, a hexahedral finite element mesh is used to construct structures including the acetabular fossa, obturator foramen, pubic tubercle, ischial tuberosity, iliac body, and iliac wing, as Figure 7 shown.

[0076] For the rectangular geometric model, the "Hexahedral-box" method is adopted, that is, in the "HEXA BLOCK" module, the "Boxes" instruction is used to construct an initial "Box" that matches the rectangular geometric model. Then, according to the geometric distribution of the surface patches, the "Box" is reasonably divided to form multiple sub-blocks. Subsequently, the nodes on the "Box" are moved to positions near the corresponding geometric nodes to ensure that the nodes of the "Box" model are highly aligned with the geometric features of the original geometric model. For the trapezoidal geometric model, the "Hexahedral-box-box" method is adopted. First, as Figure 3 (a) shown, the surface patches of the trapezoidal geometric model are analyzed in segments, and based on its geometric features and the shape of the patches, the entire model is reasonably divided into several sub-regions. For each sub-region, a corresponding "Box" is independently created to ensure that each "Box" can accurately cover its corresponding surface patch, as Figure 3 (b) shown. After all the "Boxes" are created, the "face-to-face" fitting operation between adjacent two "Boxes" is implemented using the "Paste" command, as Figure 3(c). Through this command, the corresponding faces of the two selected "Boxes" are directly joined together, thus ensuring the precise alignment of their geometric boundaries at the contact positions and forming a common-edge relationship. Finally, as Figure 3 (d) shows, point-to-point and line-to-line joining operations are carried out to ensure the tight fit between the "Box" structure and the rectangular geometric model, so as to improve the integrity and structural stability of the overall geometric model; this operation not only improves the overall geometric consistency of the model, but also effectively avoids errors caused by gaps or overlaps between different "Boxes". After completing the above steps, the number of "Box" edges can be set, as Figure 3 (e) shows. Then, through the "Volume Mesh" instruction, the entire joined "Box" is meshed with pure hexahedrons, and finally a hexahedral finite element mesh is obtained, as Figure 3 (f) shows. For columnar geometric models, the "O-Grid structure", that is, the "butterfly grid", is adopted. By using the "O-Grid" command to select the frame surface of the joined "Box" and offset it inward, an orthogonal structure, that is, the so-called "butterfly structure", can be effectively constructed. This method not only optimizes the utilization efficiency of the internal space of the geometry, but also enhances the geometric characteristics of the model.

[0077] To ensure the generation of high-quality finite element meshes, the present invention proposes a "layered mesh" method. As Figure 4 (a) shows, it is the geometric model of the joined "Box". After the hexahedral meshing of this geometric model, the internal mesh arrangement is as Figure 4 (b) shows, the middle mesh size is large and the mesh sizes at both ends are small, and the overall mesh distribution is uneven. Therefore, the "Split" instruction is used to evenly divide the geometric model of the joined "Box", as Figure 4 (c) shows. Through this operation, the contour of the geometric model can be better constrained and the arrangement of the internal meshes can be improved. Figure 4 (d) shows the internal node distribution of the "Box" after splitting. The sorting and layout control of the internal meshes can be achieved by moving the nodes. Through the above operations, the quality of the finite element mesh is significantly improved, and the specific results are as Figure 4 (e) shows, showing a more reasonable and uniform mesh distribution, laying a good foundation for subsequent finite element analysis.

[0078] (3) Method for adjusting the physiological curvature of the spine of automotive occupants with the physical signs of the 95th percentile male in China.

[0079] When the volunteer undergoes a CT image scan, he is in a lying position, and his physiological curvature is as Figure 5(As shown in (a)), it is necessary to correct it according to the normal spinal physiological structure to conform to the physiological curvature of the spine in the sitting posture of the occupant. Import the image of the normal physiological curvature of an adult into the Catia software, and use the point-by-point method to mark 3 points in the upper, middle, and lower regions on the front surface of each vertebral body of 7 cervical vertebrae (C1-C7), 12 thoracic vertebrae (T1-T12), and 5 lumbar vertebrae (L1-L5), and mark 1 point on the upper surface of the front end of the sacrum. Connect the 73 points with a spline curve to obtain the standard physiological curvature curve of the adult spine, as Figure 5 (b) shown. Import it into the ANSA software, use the sacrum as the reference, fit the end sacral point to the sacrum, and then scale the curve to make it conform to the size of the model spine. Translate and rotate each vertebral body separately to make it fit the points on the curve, and finally obtain the physiological curvature of the spine of the bionic model of male physical signs at the 95th percentile in China, as Figure 5 (c) shown.

[0080] For the intervertebral disc structure between vertebral bodies, use the "Elements" command in the "Mesh" module to select the corresponding mesh surfaces between the upper vertebral body (i.e., the lower surface of the upper vertebral body) and the lower vertebral body (i.e., the upper surface of the lower vertebral body) to generate hexahedral meshes, and then use the "Solid Builder" command to sequentially generate volume meshes along the mesh edges of the vertebral body structure to ensure that the volume meshes of each intervertebral disc can be seamlessly combined with the vertebral body structures at both ends to construct the annulus fibrosus. After completing the preliminary generation of volume meshes, use "Split Cases" to cut the overall mesh along the outer edge to make the meshes evenly distributed. Finally, select the hexahedral mesh nodes on the periphery of the intervertebral disc through "MOVE GRIDS" and offset them at a certain distance according to the radius range to simulate the arc structure of the outer surface of the annulus fibrosus.

[0081] (4) Method for determining and adjusting the sitting posture of an automotive digital evaluation model with male physical signs at the 95th percentile in China.

[0082] Referring to the comfortable angle range of the trunk (i.e., the normal sitting posture angle range of the occupant) in the standard sitting posture of a male at the 95th percentile, the upper arm angle is 0° - 30°, the lower arm angle is 120° - 160°, the backrest angle is 20° - 30°, the angle between the trunk and the thigh is 95° - 115°, the knee angle is 100° - 145°, and the ankle angle is 87° - 110°. Adjust the bionic model of injury to the occupant posture with the pelvic structure as the reference. As Figure 8 shown, adjust the corresponding upper arm angle, lower arm angle, backrest angle, trunk angle, knee angle, and ankle angle according to the rotation centers of the shoulder joint, elbow joint, wrist joint, hip joint, knee joint, and ankle joint.

[0083] (5) Method for optimizing and adjusting the muscles of an automotive digital evaluation model with male physical signs at the 95th percentile in China.

[0084] When the upper and lower limbs of the human body flex and stretch, the corresponding muscles will also be compressed and stretched accordingly. According to the principles of skeletal muscle movement anatomy, it is necessary to optimize the muscles in the injury bionic model to make them more conform to the muscle morphology in the human sitting posture.

[0085] For areas with small movement amplitudes, such as the shoulder joint, elbow joint, wrist joint, and ankle joint, simple deformation of the muscles in this area is carried out, that is, stretching and compression are performed through "MORPH" to adjust the penetration between areas to make it conform to the anatomical structure characteristics; for areas with large movement amplitudes, such as the hip joint and knee joint, the range of muscle deformation in this area is large, and simple stretching and compression cannot guarantee the mesh quality and will also cause distortion of the model. As Figure 9 (a) shows an uncorrected muscle finite element model; a "Box" is constructed for it through "MORPH", as Figure 9 (b) shows that to achieve the optimal correction effect, "Boxes" can be created in segments;

[0086] The muscles are stretched and compressed by moving the nodes above the "Box", and the corrected muscles are as shown in Figure 9 (c); 2D shell elements are generated on the overall surface of the deformed muscles through "Vol.Shell", and it is re-imported into Geomagic to generate a new muscle geometric model, as Figure 9 (d) shows; the new geometric model is re-meshed with surface patches, as Figure 9 (e) shows; finally, according to the method in (2) above, a corrected finite element model is obtained, as Figure 9 (f) shows.

[0087] (6) Connection of the digital evaluation model of a car with the physical characteristics of the 95th percentile Chinese male.

[0088] The connection of the head, neck, chest, abdomen, pelvis, and limbs of the injury bionic model is realized through ligaments, tendons, fat, and skin. "Faces" are constructed between bones to simulate ligament structures; "Faces" are first constructed between bones and muscles, and then pentahedrons are generated on the surfaces of hexahedrons and adjacent shell elements through the "Elements" command. The constructed 2D shell elements and pentahedrons simulate tendon structures; the fat structure is constructed through the peripheral skin geometric model. To make the grid distribution of the fat structure uniform, the skin geometric model is first divided, and then the overall model structure is surface-enveloped (2D shell elements) to construct fascia, and finally the projection of the fascia onto the skin geometric surface is realized through the "Extrude" command; finally, a layer of 2D shell element structure is generated on the constructed fat surface through the "Vol.Shell" command to simulate the skin structure. As Figure 10As shown, it is the digital evaluation model of a vehicle with the physical characteristics of the 95th percentile Chinese male in the present invention.

[0089] In the digital evaluation model of the vehicle occupant posture with the physical characteristics of the 95th percentile Chinese male in the present invention, the muscle structure is relatively detailed in the upper limbs, lower limbs, chest and abdomen, and pelvis. However, in the finite element dummy model in the prior art, the muscle structure is not detailed, and the upper and lower limb muscles adopt an equivalent muscle model without subdividing the muscle structure.

[0090] The advantage of using hexahedral meshes in the present invention is that there are more contact surfaces between hexahedral elements, so more interpolation information can be obtained, and it has a faster convergence speed, showing obvious advantages in numerical simulation.

[0091] As Figure 11 shown, place the digital evaluation model of the vehicle with the physical characteristics of the 95th percentile Chinese male disclosed in the present invention on the seat to simulate a frontal collision test and study the injury mechanism of Chinese 95th percentile male vehicle occupants; as Figure 12 shown, output the accelerations of the head, the 1st thoracic vertebra (T1), the 8th thoracic vertebra (T8), and the pelvis of the model in the test, which can be used to evaluate the human body injury in a vehicle frontal collision.

[0092] Move the digital evaluation model of the vehicle with the physical characteristics of the 95th percentile Chinese male to the seat through the "translation" and "rotation" tools to ensure contact between the model and the seat without penetration; in the Primer software, construct a three-point seat belt for the model, adjust the seat belt path to make the shoulder belt and waist belt fit the model, set the magnitudes of the seat belt pre-tension force and retractor force, and endow the seat belt with material properties. In the ANSA software, select the *CONTACT_AUTOMATIC_SINGLE_SURFACE keyword to define the self-contact between the various tissue structures of the injury bionic model, select the *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE keyword to define the contact between the model and the seat belt and the seat, select the *DATABASE_HISTORY_NODE(_ID) keyword to define the measurement points on the head, thoracic vertebra T1, thoracic vertebra T8, and pelvis of the model; set the gravity field for the digital evaluation model of the vehicle with the physical characteristics of the 95th percentile Chinese male and the seat model; apply an acceleration curve to the seat model to conduct a frontal collision test; output the corresponding kinematic and biomechanical parameters of the digital evaluation model of the vehicle with the physical characteristics of the 95th percentile Chinese male, and comprehensively evaluate the injury situation of the Chinese 95th percentile male vehicle occupants.

[0093] The present invention provides a digital evaluation model for automobiles with the physical characteristics of the 95th percentile male in China, which is an important tool for the integrated research of active and passive vehicle safety and the R & D of safety protection devices. The digital evaluation model for automobiles is developed and applied based on finite element software, and is mainly used for analyzing human body injuries during vehicle collisions, also known as a biomechanical model; the model conforms to the latest measurement statistics of the height data of the 95th percentile male in China by the China National Institute of Standardization; the model has detailed human anatomical structure characteristics, and corresponding material properties are assigned to different tissue structures in the model with reference to their mechanical characteristics. The present invention can provide basic data and technical support for vehicle design and safety research, road traffic accident research, medical research and medical device design, and emergency rescue implementation.

[0094] The protection scope of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, all changes and advantages that can be conceived by those skilled in the art are included in the present invention, and the scope of protection is defined by the appended claims.

Claims

1. A digital evaluation model for occupant posture of a vehicle with the physical characteristics of the 95th percentile Chinese male, characterized in that, The characteristic dimensions of the model conform to the statistical data of the physical signs of Chinese men at the 95th percentile newly measured by the China National Institute of Standardization. The weight of the model is 85.3 kg, the sitting height is 99.9 cm, the shoulder width is 41.5 cm, the maximum shoulder width is 49.4 cm, the chest thickness is 25.6 cm, the chest width is 31.8 cm, the number of elements is 1.536 million, and the number of nodes is 1.203 million; the model has detailed human anatomical structure characteristics, including bone, muscle, visceral tissue, fat, soft tissue, ligament, tendon and skin structure; the model uses hexahedron elements, quadrilateral shell elements, pentahedron elements and / or triangular shell elements for simulation according to different structures and parts of the human body, and the various tissue structures are connected by the way of co-nodes; the tissue structures in the model are given corresponding material properties according to their different mechanical properties, and the contact is defined according to the tissue structure relationship. The model uses a hexahedron finite element mesh to construct a heart structure including the left atrium, right atrium, left ventricle, right ventricle, pulmonary artery, aorta, superior vena cava and inferior vena cava structures, constructs a sacral structure including the sacral canal, anterior sacral foramina and posterior sacral foramina structures, and constructs a hip bone structure including the acetabular fossa, obturator foramen, pubic tubercle, ischial tuberosity, iliac body and iliac wing.

2. A method for constructing a digital evaluation model of occupant posture for a vehicle with the physical characteristics of the 95th percentile male in China, characterized in that, The construction method specifically includes: Step A: According to the latest human physical sign statistical data, obtain the CT image data of volunteers who meet the physical signs of Chinese men at the 95th percentile in multiple times, and reconstruct the human geometric model according to the CT image data. Step B: Perform finite element mesh division on the human geometric model obtained in Step A to construct finite element models of various tissue structures including the heart, sacrum, hip bone and spine finite element models; the heart, the sacrum and the hip bone are constructed by pure hexahedron elements, and the spine is constructed by hexahedron elements and quadrilateral shell elements. Step C: Correct the physiological curvature of the spine for the spine finite element model constructed in Step B, and construct the intervertebral disc, nucleus pulposus, annulus fibrosus and ligament; use the "Move" command to select the nodes of the annulus fibrosus at different positions of the spine on the hexahedron mesh for offset to simulate the arc structure of the outer surface of the annulus fibrosus. Step D: Connect the finite element models of various tissue structures constructed in Step B and the spine finite element model with adjusted physiological curvature constructed in Step C by means of tendons and ligaments to form a finite element model of a Chinese male standing posture at the 95th percentile of physical signs. Step E: Adjust the standing finite element model obtained in Step D to the occupant posture according to the normal sitting posture angle range of the occupant, and reversely optimize and adjust the muscle mesh division. Step F: Connect the various tissue structures of the Chinese male automobile finite element model at the 95th percentile of physical signs that has been adjusted to the occupant posture, and finally obtain an automobile digital evaluation model with the occupant posture of Chinese men at the 95th percentile of physical signs.

3. The construction method according to claim 2, characterized in that In Step A, the human body is reconstructed according to the CT image data for bone, muscle, visceral tissue, soft tissue and skin structure. The human geometric model is divided into a rectangular geometric model, a trapezoidal geometric model and a columnar geometric model according to its shape. and / or The reconstruction of the human geometric model includes the following sub-steps: Step A1: In Mimics software, geometric extraction of each tissue structure is performed with different gray value ranges for bone, fat, skin, internal organs, and muscle structures, and a 3D model is generated; Step A2: For the generated 3D model, in Mimics software, use the "Smooth" command to define the smoothing coefficient, use the "Reduce" command to define the tolerance and edge angle, use the "Wrap" command to define the gap closing distance, perform "Smooth", "Reduce", and "Wrap" definition processing on the surface of the geometric model and output it in the *.STL file format; Step A3: Import the *.STL file obtained in Step A2 into Geomagic software, perform operations on the geometric model including refinement, fast smoothing, relaxation, removing spikes, and removing features; optimize the edge curvature of the geometric model, repair the holes in the geometric model, use Boolean operations to optimize the geometric shape of adjacent geometric models, and finally fit the smoothed model into a NURBS surface and convert it into a CAD model in the *.SAT format for output; and / or The gray value ranges of different tissue structures are as follows: bone is [148, 661], fat is [-51, 205], skin is [-718, -177], muscle is [-5, 135], and internal organs are [-178, 146]; and / or Use the "Smooth" command to define the smoothing coefficient as 0.6, use the "Reduce" command to define the tolerance as 1 mm, define the edge angle as 10°, and use the "Wrap" command to define the gap closing distance as 5 mm.

4. The construction method according to claim 2, characterized in that In Step B, use hexahedral finite element meshes to construct a heart structure including the left atrium, right atrium, left ventricle, right ventricle, pulmonary artery, aorta, superior vena cava, and inferior vena cava structures, construct a sacral bone structure including the sacral canal, anterior sacral foramina, and posterior sacral foramina structures, construct a hip bone structure including the acetabular fossa, obturator foramen, pubic tubercle, ischial tuberosity, iliac body, and iliac wing, and construct a spinal column structure including vertebral bones, intervertebral discs, and spinal cord; use tetrahedral shell elements to construct the ligament structure on the spinal column; and / or The method for dividing the finite element meshes includes the following sub-steps: Step B1: Import the geometric model processed in Step A into ANSA software in the *.SAT format; Step B2: For a rectangular geometric model, use the "Hexahedral-box" method. In the "HEXA BLOCK" module, use the "Boxes" command to create a "Box" for the entire geometric model, divide the "Box" according to the distribution position of the surface patches, move the nodes on the "Box" to the intersection points of the contour lines on the surface patches, and then perform point-to-point and line-to-line fitting; and / or For a trapezoidal geometric model, use the "Hexahedral-box-box" method. Segment the geometric model to create "Boxes" according to the surface patches, and use the "Paste" command to perform "face-to-face" fitting of the corresponding faces of two adjacent "Boxes" so that the "Boxes" share an edge; and / or For the columnar geometric model, the "O-Grid structure" is adopted. The box surface that has been fitted to the "Box" is selected by the "O-Grid" command and offset inward to construct an orthogonal butterfly structure; Step B3: Adopt the "layered grid" method to evenly divide the key areas that have been fitted to the "Box" and constrain the internal grid distribution; Step B4: According to the grid size requirements, set the number of grids for the edges that have been fitted to the "Box" through the "Number" command; Step B5: Through the "Volume Mesh" instruction, perform pure hexahedron mesh division on the entire fitted "Box". By smoothing the constructed hexahedron mesh, the hexahedron mesh division of the geometric model is completed; and / or The grid size requirements are that the maximum element size does not exceed 12 mm and the minimum element size does not exceed 1 mm.

5. The construction method according to claim 2, characterized in that In step C, for the annulus fibrosus at different positions on the spine, the average offset distance of the annulus fibrosus in the cervical spine part is 0.6 - 0.8 mm; the average offset distance of the annulus fibrosus in the thoracic spine part is 0.8 - 1.0 mm; the average offset distance of the annulus fibrosus in the lumbar spine part is 1.0 - 1.2 mm; and / or The correction and construction of the spinal physiological curvature include the following sub-steps: Step C1: Use the point plotting method to take points on the front surface of the upper, middle, and lower three regions of the front surface of 24 vertebral bodies of the normal spine and the upper surface of the front end of the sacrum along the median sagittal plane of the human body, and connect the selected 73 points with a spline curve to obtain the physiological curvature curve of the normal spine; Step C2: Import the obtained physiological curvature curve of the normal spine into the ANSA software and perform scaling so that the physiological curvature curve of the spine is the same size as the finite element model of the spine; Step C3: Taking the sacrum as the reference, fit the end sacral point of the physiological curvature curve of the normal spine to the sacrum, and then translate and rotate each vertebral body separately to make it fit the points on the curve, and finally obtain the physiological curvature of the spine of the 95th percentile male with Chinese physical signs; Step C4: Through the "Elements" instruction under the "MESH" module, complete the construction of the intervertebral disc between every two adjacent upper and lower vertebral bodies; use the "Solid Builder" command to construct the annulus fibrosus around the edge of the constructed intervertebral disc with the lower surface of the upper vertebral body and the upper surface of the lower vertebral body as the boundaries, and then move the nodes on the finite element mesh of the annulus fibrosus through the "Move" command to simulate the arc structure of the outer surface of the annulus fibrosus; Step C5: By constructing quadrilateral meshes to simulate the structures including the zygapophyseal joint capsule, articular cartilage, interspinous ligament, supraspinous ligament, transverse process ligament, ligamentum flavum, anterior longitudinal ligament, and posterior longitudinal ligament between the vertebral bodies, a finite element model of the spine of the 95th percentile male that conforms to the normal physiological curvature is obtained.

6. The construction method according to claim 2, wherein, In step D, the construction of the finite element model of the standing posture of the 95th percentile male with Chinese physical signs includes the following sub-steps: Step D1: Taking the finite element model of the head as the reference, connect the corrected and constructed finite element model of the spine in step C with the finite element model of the head; Step D2: Adjust and connect the rib finite element model according to the human anatomical structure, and simulate the connection part between muscles and bones through 2D shell elements and hexahedrons. Step D3: Symmetrize the upper and lower limb finite element models according to the median sagittal plane of the human body, and connect them to the corresponding bones through ligaments and tendons. Step D4: Import the smoothed skin geometric model into ANSA software, construct fat through "projection", and finally obtain a finite element model of a 95th percentile male standing posture with Chinese physical characteristics.

7. The construction method according to claim 2, characterized in that, In step E, the adjustment of the sitting posture of a male occupant with 95th percentile Chinese characteristics includes the following sub-steps: Step E1: Taking the pelvic structure as a reference, adjust the 95th percentile male standing posture finite element model to the occupant posture. Step E2: Adjust the corresponding upper arm angle, forearm angle, backrest angle, torso angle, knee angle, and ankle angle of the 95th percentile male finite element model according to the rotation centers of the shoulder joint, elbow joint, wrist joint, hip joint, knee joint, and ankle joint within the normal sitting posture angle range of the occupant. Step E3: Calibrate and connect the muscle finite element model in the sitting posture; for muscle structures including the gluteus maximus, rectus femoris, long head of the biceps femoris, lateral head of the gastrocnemius, and medial head of the gastrocnemius, re-divide the surface patches using reverse engineering methods and import them into ANSA software for re-meshing. and / or The normal sitting posture angle range includes: upper arm angle 0° - 30°, forearm angle 120° - 160°, backrest angle 20° - 30°, angle between torso and thigh 95° - 115°, knee angle 100° - 145°, ankle angle 87° - 110°.

8. An automotive digital evaluation model with the posture of an occupant with 95th percentile male physical characteristics of China constructed by the method according to any one of claims 2 - 7.

9. The application of the digital evaluation model according to claim 1 or 8, or the construction method according to claims 2 - 7 in automotive design and safety research, road traffic accident research, medical research and medical device design, and emergency rescue implementation.

Images