A pre-simulation adjustment method for posture transformation of a human body finite element model

Abstract

The present application relates to the technical field of safe virtual evaluation, in particular to a pre-simulation adjustment method for posture transformation of a human body finite element model, comprising: S1, analyzing a human body model of an initial posture and a target posture, and determining posture transformation parameters, the posture transformation parameters comprising limb parts for posture transformation and rotation angles of rotating joints, the limb parts for posture transformation comprising parts or all of left upper limbs, right upper limbs, left lower limbs and right lower limbs; the rotating joints comprising limb joints and trunk joints; S2, performing preliminary transformation pre-simulation of the limb parts; and S3, performing complete transformation pre-simulation of the limb parts.The pre-simulation adjustment method can quickly adjust the posture of the limbs of the human body finite element model, greatly reducing the workload of grid reconstruction; and can ensure that the transition position grids at the joints are smooth and natural, ensuring the grid quality and the biological fidelity of the human body finite element model.

Description

Technical Field

[0001] This invention relates to the field of safety virtual assessment technology, specifically a pre-simulation adjustment method for posture transformation of a human finite element model. Background Technology

[0002] The assessment of human injury in automotive safety is developing towards a fusion of virtual and real methods, and in the future, it may even achieve full-process, all-round virtual safety assessment. The human finite element model is widely considered a tool for predicting and assessing human injury as required by virtual safety assessments. A fully validated human finite element model with human characteristics can predict injuries to vehicle occupants and pedestrians in traffic accidents, which is of great significance for the development of automotive safety and the protection of road users.

[0003] Currently, human finite element models provide several typical walking and occupant postures. However, the posture of the human body during traffic accidents is often diverse. Accurately simulating injury prediction under various postures requires posture transformation of the human finite element model. In existing technologies, transforming the human finite element model into a specific posture often requires a cumbersome mesh reconstruction stage, which greatly increases the workload of model prediction of human injury. On the other hand, mesh reconstruction methods often struggle to ensure geometric smoothness and naturalness at joint connections, making it difficult to guarantee the biological realism of the model. Summary of the Invention

[0004] This invention provides a pre-simulation adjustment method for posture transformation of a human finite element model. This method can quickly adjust the posture of the limbs of the human finite element model, greatly reducing the workload of mesh reconstruction. Furthermore, the pre-simulation adjustment method can ensure that the mesh geometry at the transition position of the joint is smooth and natural, ensuring mesh quality and the biological realism of the human finite element model.

[0005] This application provides the following technical solution:

[0006] A pre-simulation adjustment method for posture transformation of a human finite element model includes the following steps:

[0007] S1. Analyze the human body model of the initial posture and the target posture, and determine the posture transformation parameters. The posture transformation parameters include the limb parts of the posture transformation and the rotation angle of the rotation joints. The limb parts of the posture transformation include part or all of the left upper limb, right upper limb, left lower limb, and right lower limb. The rotation joints include limb joints and trunk joints.

[0008] S2. Conduct preliminary simulation of limb transformations;

[0009] S3. Perform a pre-simulation of the complete transformation of the limb parts.

[0010] Furthermore, step S2 includes the following steps:

[0011] S21. Complete the preliminary preparations for the initial transformation pre-simulation;

[0012] S22. Conduct preliminary simulation of limb transformations;

[0013] S23. Inspect and repair the human body model obtained from the preliminary transformation pre-simulation.

[0014] Furthermore, S21 includes:

[0015] S211. Localize the entire trunk, limb bones and corresponding subcutaneous tissues into rigid bodies.

[0016] S212. Preserve the easily deformable subcutaneous tissue in its original state;

[0017] S213, Force displacement of the locally rigidized bones in S211.

[0018] Furthermore, S22 includes:

[0019] S221. Create a separate K-file for the mesh nodes of the attitude transformation part before simulation;

[0020] S222, Simulation pre-simulation calculation;

[0021] S223. Create a separate K-file for the mesh nodes of the attitude transformation part after simulation;

[0022] S224. Replace the K-file before simulation in step S221 with the K-file containing the mesh nodes of the attitude transformation part after simulation in step S223.

[0023] Furthermore, S23 includes:

[0024] S231. Repair the mesh of the ligaments at the joint;

[0025] S232. Perform a quality check on the preliminary transformation and pre-simulation of the human body model.

[0026] Furthermore, S3 includes:

[0027] S31. Complete the pre-simulation preparations for the full transformation;

[0028] S32. Perform a pre-simulation of the complete transformation of the limb parts;

[0029] S33. Inspect and repair the human body model obtained from the complete transformation pre-simulation.

[0030] Furthermore, S31 includes:

[0031] S311. Localize the entire torso, limb bones and corresponding subcutaneous tissues into rigid bodies.

[0032] S312. Preserve the easily deformable subcutaneous tissue in its original state;

[0033] S313, Force displacement of the locally rigidized bones in S311.

[0034] Furthermore, S32 includes:

[0035] S321. Create a separate K-file for the mesh nodes of the attitude transformation part before simulation;

[0036] S322, Simulation pre-simulation calculation;

[0037] S323. Create a separate K-file for the mesh nodes of the attitude transformation part after simulation;

[0038] S324. Replace the K-file before simulation in step S321 with the K-file containing the mesh nodes of the attitude transformation part after simulation in step S323.

[0039] Furthermore, S33 includes:

[0040] S331. Repair the mesh of the ligaments at the joint;

[0041] S332. Perform a quality check on the human body model of the complete transformation pre-simulation.

[0042] Further: In S2, a preliminary transformation pre-simulation is performed on the limbs simultaneously; in S3, a complete transformation pre-simulation is performed on the limbs simultaneously.

[0043] The principles and advantages of this invention are as follows:

[0044] Compared to traditional methods that reconstruct the entire mesh for human body model pose transformation, this invention locally rigidifies the human body model, enabling rapid adjustment of the limb poses. In the specific adjustment process, rigid body inertia points are established for each limb using both torso joints and limb joints. The pose transformation of a limb is defined as a forced displacement of three degrees of freedom occurring within the local coordinate system of the corresponding limb segment at the rigid body inertia point. Furthermore, the simulation is divided into preliminary transformation and complete transformation, simulating both the overall limb and local limb poses separately, ultimately yielding a complete human body model with pose transformation.

[0045] This method can quickly adjust the posture of the limbs of the human finite element model, greatly reducing the workload of mesh reconstruction; moreover, the pre-simulation adjustment method can ensure that the mesh geometry at the transition position of the joint is smooth and natural, ensuring mesh quality and the biological realism of the human finite element model. Attached Figure Description

[0046] Figure 1 This is a flowchart of a pre-simulation adjustment method for posture transformation of a human finite element model;

[0047] Figure 2 A schematic diagram of the fixed rigid body parts for overall posture changes of the upper limb;

[0048] Figure 3 This is a schematic diagram of a localized rigid body part of the upper limb.

[0049] Figure 4 A time curve of the angle rotation of the upper limb joints;

[0050] Figure 5 A schematic diagram of the fixed rigid body part for forearm posture transformation;

[0051] Figure 6 This is a schematic diagram of a locally rigidified part of the forearm.

[0052] Figure 7 This is a schematic diagram of the pose transformation of a human body model. Detailed Implementation

[0053] The following detailed description illustrates the specific implementation method:

[0054] In this embodiment, the posture adjustment of the human finite element model mainly targets the posture of the limbs, and does not involve the posture transformation of the torso. The process is as follows: Figure 1 As shown.

[0055] Example 1

[0056] This embodiment describes a pre-simulation adjustment method for posture transformation of a human finite element model. In this embodiment, the posture of the left upper limb is adjusted, corresponding to a human model where a single upper limb is moving while standing in place. The method includes the following steps:

[0057] S1. Analyze the human body model of the initial posture and the target posture, and determine the posture transformation parameters. The posture transformation parameters include the limb parts of the posture transformation and the rotation angle of the rotation joints. The limb parts of the posture transformation include part or all of the left upper limb, right upper limb, left lower limb, and right lower limb; the rotation joints include limb joints and trunk joints.

[0058] In this embodiment, the limbs involved in the posture change include the left upper arm and the left forearm. The left upper arm rotates 10° relative to the left shoulder joint in the XZ plane, and the left forearm rotates 15° relative to the left upper arm in the XZ plane. This results in a rotation angle of 10° for the left shoulder joint and a rotation angle of 15° for the left elbow joint.

[0059] S2. Conduct preliminary simulations of limb changes, primarily simulating adjustments to the overall angle of the upper limbs. Specific steps are as follows:

[0060] S21. Complete the preliminary preparations for the initial transformation pre-simulation, including the following steps:

[0061] S211. Localize the entire torso, limb bones, and corresponding subcutaneous tissues into rigid bodies:

[0062] During the adjustment of the overall angle of the upper limb, the trunk and lower limb remain fixed, while the upper limb rotates with the shoulder joint. The upper limb includes the forearm, elbow joint, and humerus, as well as the subcutaneous tissue covering the forearm, elbow joint, and humerus.

[0063] use The PART keyword is used to create beam cells, and... The MAT_RIGID keyword is assigned to rigid body materials, using The SET_PART keyword creates separate set units for the lower limbs and trunk (excluding subcutaneous tissue of the chest), using... The `DEFORMABLE_TO_RIGID` keyword binds the created set elements to rigid body beam elements, making the lower limbs and torso (excluding subcutaneous tissue of the chest) rigid bodies and restricting six degrees of freedom to ensure that this part remains stationary during the simulation. Figure 2 As shown;

[0064] The forearm, elbow joint, and humerus are rigidified to form a rigid body. PART_INERTIA inertial point and its use DEFINE_COORDINATE_SYSTEM establishes a local coordinate system `system` at the center of shoulder joint rotation, setting the rotational inertia and mass of the inertia point along three degrees of freedom. The MAT_RIGID keyword assigns an inertial point to the rigid body material, using... The `DEFORMABLE_TO_RIGID` keyword binds the forearm, elbow, and humerus to rigid body inertia points, and also binds the subcutaneous tissue covering these areas to these points, thus making this part rigid. Figure 3 As shown.

[0065] S212. Preserve easily deformable subcutaneous tissue in its original state:

[0066] Based on the historical database of human body finite element model posture transformation, during the posture transformation of the upper limb, the subcutaneous tissue of the upper arm, the subcutaneous tissue of the shoulder joint, the shoulder ligaments, and the subcutaneous tissue of the chest will undergo mesh deformation. Therefore, it is necessary to preserve the original material properties of this part of the mesh.

[0067] S213. Force displacement of the locally rigidified skeleton in S211:

[0068] The forced displacement adjustment of the skeleton is divided into two stages: the first stage is to rotate the rigid forearm, elbow and humerus at different angles; the second stage is to restore the subcutaneous tissue of the upper arm, shoulder and chest to their natural state after the posture is determined to be adjusted to the target position, so as to ensure the mesh quality and bio-realism of the model.

[0069] Assuming the upper limb angle needs to be adjusted by 10°, the formula for converting radians to angles is:

[0070]

[0071] use BOUDARY_PRESCRIBED_MOTION_RIGID forces displacement on the rigidified portion in step S211, specifically according to the following function:

[0072] RAD = a t

[0073] Where RAD is the rotational radius of the rigid part, a is the radian conversion coefficient, and t is the simulation time.

[0074] The curve of the radian-time function is as follows Figure 4 As shown.

[0075] In the simulator software, set the scaling factor SF to 0.174 to ensure that the upper limb rotation angle is about 10°.

[0076] S22. Conduct preliminary simulation of limb transformations, including the following steps:

[0077] S221. Create a separate K-file for the mesh nodes of the attitude transformation part before simulation:

[0078] Use the include function to move the mesh nodes of the posture adjustment section and the subcutaneous tissue section in the transition area into a new K file.

[0079] S222, Simulation Pre-simulation Calculation:

[0080] After the preparatory work for attitude transformation is completed, the model is simulated and calculated. The simulation calculation time is about 2 hours.

[0081] S223. Create a separate K-file for the mesh nodes of the attitude transformation part after simulation:

[0082] In the simulation animation, the mesh data of the human finite element model when it is stationary after the pre-simulated posture adjustment is selected. A new K file is created using the include function, and the mesh nodes of the posture adjustment part and the subcutaneous tissue part in the transition area are transferred into this K file. The newly created K file is named the same as the K file in step S221.

[0083] S224. Replace the K-file before simulation in step S221 with the K-file containing the mesh nodes of the post-simulation attitude transformation part in step S223. At this time, the initial attitude transformation of the upper limb model is completed.

[0084] S23. Inspect and repair the human body model obtained from the preliminary transformation simulation, specifically including the following steps:

[0085] S231. Repair the mesh of the ligaments at the joint:

[0086] In the simulation, some shell element ligaments will be squeezed and deformed, causing mesh wrinkling, mainly in the shoulder and elbow joints. These parts of the mesh need to be simply repaired and rebuilt.

[0087] S232. Perform a quality check on the preliminary transformation pre-simulation human body model:

[0088] This includes posture checks and mesh quality checks. The posture angles of the human finite element model, after initial transformation, pre-simulation, and mesh repair, are checked, including the overall angle of the upper limbs and the angle between the upper arm and forearm, to ensure the adjusted angles meet requirements. On the other hand, the mesh quality of the joints in the human finite element model is checked to ensure the mesh quality meets standards.

[0089] S3. Perform a complete pre-simulation of the limb transformation, mainly adjusting the angle of the forearm, including the following steps:

[0090] S31. Complete the preliminary preparations for the full transformation pre-simulation, as follows:

[0091] S311. Localize the entire torso, limb bones, and corresponding subcutaneous tissues into rigid bodies:

[0092] During the simulation of forearm pose transformation, the lower limbs, torso, shoulder joint, and humerus need to remain fixed. The PART keyword is used to create beam cells, and... The MAT_RIGID keyword is assigned to rigid body materials, and used... The SET_PART keyword creates separate set units for the lower limbs and trunk (excluding subcutaneous tissue of the chest), using... The `DEFORMABLE_TO_RIGID` keyword binds the created set elements to rigid beam elements, making the lower limbs, torso, shoulder joint, and humerus rigid bodies and restricting six degrees of freedom to ensure that these parts remain fixed during simulation. Figure 5 As shown.

[0093] The forearm portion (excluding the subcutaneous tissue) was rigidified to create a... PART_INERTIA inertial point and its use DEFINE_COORDINATE_SYSTEM establishes a local coordinate system `system` with the elbow joint rotation center as the inertial point, and sets the rotational inertia and mass of the inertial point along three degrees of freedom. The MAT_RIGID keyword assigns an inertial point to the rigid body material, using... The `DEFORMABLE_TO_RIGID` keyword binds the forearm portion (excluding subcutaneous tissue) to a rigid body inertia point, making that portion rigid. Figure 6 As shown.

[0094] S312. Preserve easily deformable subcutaneous tissue in its original state:

[0095] Based on the historical database of human body finite element model posture transformation, during the process of adjusting the forearm angle posture, the subcutaneous tissue of the forearm, elbow joint subcutaneous tissue and elbow ligament will undergo mesh deformation. Therefore, it is necessary to retain the original material properties of this part of the mesh.

[0096] S313. Force displacement of the locally rigidified bones in S311:

[0097] Assuming the forearm rotates 15° relative to the upper arm, the angle between the forearm and upper arm needs to be adjusted by 15°. The formula for converting radians and angles is as follows:

[0098]

[0099] use BOUDARY_PRESCRIBED_MOTION_RIGID forces the rigid body part in step S311 to be displaced. The displacement is simulated according to the curve set in step 213, and the scaling factor SF is modified to 0.262 to ensure that the angle between the upper and lower arms is 15°.

[0100] After determining that the posture has been adjusted to the target position, restore the movement state of the subcutaneous tissues of the forearm and elbow joint to a natural state.

[0101] S32. Perform a complete pre-simulation of the limb transformation, including the following steps:

[0102] S321. Create a separate K-file for the mesh nodes of the attitude transformation part before simulation:

[0103] Use the include function to move the mesh nodes of the posture adjustment section and the subcutaneous tissue section in the transition area into a new K file.

[0104] S322. After the preliminary preparations are completed, start the simulation pre-simulation calculation of the model.

[0105] S323. Create a separate K-file for the mesh nodes of the attitude transformation part after simulation:

[0106] In the simulation animation, the mesh data of the human finite element model when it is stationary after the pre-simulated posture adjustment is selected. A new K-file is created using the include function, and the mesh nodes of the posture adjustment part and the subcutaneous tissue part in the transition area are transferred into this K-file. The newly created K-file is named the same as the K-file in step S321.

[0107] S324. Replace the K-file from step S321 (before simulation) with the K-file from step S323 (containing the mesh nodes for the post-simulation attitude transformation). At this point, the complete attitude transformation of the human finite element upper limb model is complete.

[0108] S33. Inspect and repair the human body model obtained from the complete transformation pre-simulation, including the following steps:

[0109] S331. Repair the mesh of the ligaments at the joint:

[0110] The elbow ligament mesh that will be squeezed and deformed in the simulation is simply repaired and reconstructed. Once the mesh quality meets the standard, the pre-simulation adjustment of the entire upper limb posture transformation is completed.

[0111] S332. Perform a quality check on the complete transformation pre-simulation human body model:

[0112] This includes posture checks and mesh quality checks. The posture angles of the human finite element model, which has been simulated and mesh-repaired, are checked to ensure that the adjusted angles meet the requirements. On the other hand, the mesh quality of the joints of the human finite element model is checked to ensure that the mesh quality meets the standards.

[0113] Example 2

[0114] In this embodiment, the posture of the limbs of the human body model is changed to correspond to the walking action of the human body model.

[0115] The difference between the pre-simulation attitude adjustment method in this embodiment and that in Embodiment 1 is:

[0116] S1. The limbs involved in the posture change include the left upper limb, right upper limb, left lower limb, and right lower limb.

[0117] The left upper limb includes the left upper arm, left elbow joint, and left forearm. The left upper arm rotates 10° relative to the left shoulder joint in the XZ plane, and the left forearm rotates 15° relative to the left upper arm in the XZ plane. Therefore, the rotation angle of the left shoulder joint is 10°, and the rotation angle of the left elbow joint is 15°.

[0118] The right upper limb includes the right upper arm, the right elbow joint, and the right forearm. Since the arms swing symmetrically in front and behind the body when the human body walks, the rotation angle of the right shoulder joint is -10° and the rotation angle of the left elbow joint is 15°.

[0119] The left lower limb includes the left thigh, right knee joint, and left calf. The rotation angle of the left hip joint is -5°, and the left knee joint does not need to rotate.

[0120] The right lower limb includes the right thigh, right knee joint, and right calf. The rotation angle of the right hip joint is 5°, and the rotation angle of the right knee joint is 5°.

[0121] S211. In the preliminary preparation steps of the initial transformation pre-simulation, use The PART keyword is used to create beam cells, and... The MAT_RIGID keyword is assigned to rigid body materials, using The SET_PART keyword creates a separate set unit for the torso (excluding the subcutaneous tissue of the chest), using... The DEFORMABLE_TO_RIGID keyword binds the created set element to the rigid beam element, making the torso (excluding the subcutaneous tissue of the chest) rigid and restricting six degrees of freedom to ensure that this part remains fixed during the simulation.

[0122] The forearm, elbow, humerus, lower leg, knee, and femur of the limbs are rigidified to create a rigid body. PART_INERTIA inertial point and its use DEFINE_COORDINATE_SYSTEM establishes local coordinate systems at the rotation centers of the shoulder and hip joints on both sides, setting rotational inertia and mass along three degrees of freedom for all inertial points. The MAT_RIGID keyword assigns all inertial points to the rigid body material, using... The `DEFORMABLE_TO_RIGID` keyword binds the forearm, elbow, and humerus to the corresponding rigid body inertia points of the shoulder joint; binds the subcutaneous tissue covering the forearm, elbow, and humerus to the corresponding rigid body inertia points of the shoulder joint; binds the lower leg, knee, and femur to the corresponding rigid body inertia points of the hip joint; and binds the lower leg, knee, and femur to the corresponding rigid body inertia points of the hip joint.

[0123] S212. Retain the original material properties of the mesh in the subcutaneous tissue of the thigh, the subcutaneous tissue of the hip joint, and the hip ligament.

[0124] S213. Force displacement of the locally rigidified skeleton in S211:

[0125] The rotation angle of the left upper limb is 10°, the rotation angle of the right upper limb is -10°, the rotation angle of the left lower limb is -5°, and the rotation angle of the right lower limb is 5°.

[0126] S231. Repair and reconstruct the mesh of the left shoulder joint, right shoulder joint, left hip joint, and right hip joint.

[0127] S232. Check the posture angles and mesh quality of the left shoulder joint, right shoulder joint, left hip joint, and right hip joint.

[0128] S311, the trunk, shoulder joint, humerus, knee joint, and femur need to remain fixed, therefore, using The PART keyword is used to create beam cells, and... The MAT_RIGID keyword is assigned to rigid body materials, and used... The SET_PART keyword creates a separate set unit for the torso (excluding the subcutaneous tissue of the chest), using... The DEFORMABLE_TO_RIGID keyword binds the created set element to the rigid body beam element, making the torso, shoulder joint and humerus, knee joint and femur rigid bodies and restricting six degrees of freedom.

[0129] The forearm (excluding subcutaneous tissue) and lower leg (excluding subcutaneous tissue) are rigid-body constructed. PART_INERTIA inertial point, and used DEFINE_COORDINATE_SYSTEM establishes local coordinate systems at the rotation centers of the elbow and knee joints as points of inertia, and sets the rotational inertia and mass along three degrees of freedom for all points of inertia. The MAT_RIGID keyword assigns all inertial points to the rigid body material, using The DEFORMABLE_TO_RIGID keyword binds the forearm portion (excluding the subcutaneous tissue of the forearm) to the corresponding rigid body inertia point, and binds the lower leg portion (excluding the subcutaneous tissue of the lower leg) to the corresponding rigid body inertia point, thus making these parts rigid.

[0130] S312. Retain the original material properties of the mesh in the subcutaneous tissue of the thighs and calves, the subcutaneous tissue of the knee joint, and the ligaments of the knee.

[0131] S313. Forcefully displace the locally rigid femur in S311:

[0132] The rotation angle of the left forearm is 15°, the rotation angle of the right forearm is 15°, and the rotation angle of the right lower leg is 5°.

[0133] S331. Repair and reconstruct the ligament mesh of the left elbow, right elbow, left knee, and right knee joints.

[0134] S332. Check the posture angles and mesh quality of the ligaments of the left elbow joint, right elbow joint, left knee joint, and right knee joint.

[0135] Using the method of this invention, after setting the posture transformation parameters of each part of the limbs, the simulation of limb posture transformation can be performed synchronously. The posture transformation time of the human finite element model can be shortened from about a week to one day, which can significantly shorten the adjustment time, improve the efficiency of human body model posture transformation, and better meet the requirements of safety virtual evaluation.

[0136] The above are merely embodiments of the present invention, and the invention is not limited to the fields covered by these embodiments. Commonly known structures and characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A pre-simulation adjustment method for posture transformation of a human finite element model, characterized in that: Includes the following steps: S1. Analyze the human body model of the initial posture and the target posture, and determine the posture transformation parameters. The posture transformation parameters include the limb parts of the posture transformation and the rotation angle of the rotation joints. The limb parts of the posture transformation include part or all of the left upper limb, right upper limb, left lower limb, and right lower limb. The rotation joints include limb joints and trunk joints. S2. Conduct preliminary transformation pre-simulation of the limbs. This preliminary transformation pre-simulation is used to adjust the overall posture changes of the limbs relative to the torso. It serves as preparation for the preliminary transformation pre-simulation, including... S21. Complete the preliminary preparations for the initial transformation pre-simulation; S211. Rigidify and fix the torso; rigidify the upper arm humerus, forearm, thigh femur, and lower leg as a whole, establish inertial points and local coordinate systems at the rotation centers of the shoulder and hip joints, and bind the entire limb segment to the corresponding inertial point. S212. Preserve the easily deformable subcutaneous tissue in its original state; S213, Force displacement of the locally rigidized bones in S211; S22. Conduct preliminary simulation of limb transformations; S23. Inspect and repair the human body model obtained from the preliminary transformation simulation; S3. Perform a full transformation pre-simulation of the limbs. This full transformation pre-simulation is used to adjust the posture changes of local limb details. It serves as preparation for the full transformation pre-simulation, including... S31. Complete the pre-simulation preparations for the full transformation; S311. Keep the trunk, shoulder joint, upper arm humerus, and thigh femur fixed and rigid; only rigidify the forearm and lower leg separately, establish inertial points and local coordinate systems at the rotation centers of the elbow and knee joints, and bind the forearm and lower leg to the corresponding inertial points. S312. Preserve the easily deformable subcutaneous tissue in its original state; S313, Force displacement of the locally rigidized bones in S311; S32. Perform a pre-simulation of the complete transformation of the limb parts; S33. Inspect and repair the human body model obtained from the complete transformation pre-simulation.

2. The pre-simulation adjustment method for posture transformation of a human finite element model according to claim 1, characterized in that: S22 includes: S221. Create a separate K-file for the mesh nodes of the attitude transformation part before simulation; S222, Simulation pre-simulation calculation; S223. Create a separate K-file for the mesh nodes of the attitude transformation part after simulation; S224. Replace the K-file before simulation in step S221 with the K-file containing the mesh nodes of the attitude transformation part after simulation in step S223.

3. The pre-simulation adjustment method for posture transformation of a human finite element model according to claim 1, characterized in that: S23 includes: S231. Repair the mesh of the ligaments at the joint; S232. Perform a quality check on the preliminary transformation and pre-simulation of the human body model.

4. The pre-simulation adjustment method for posture transformation of a human finite element model according to claim 1, characterized in that: S32 includes: S321. Create a separate K-file for the mesh nodes of the attitude transformation part before simulation; S322, Simulation pre-simulation calculation; S323. Create a separate K-file for the mesh nodes of the attitude transformation part after simulation; S324. Replace the K-file before simulation in step S321 with the K-file containing the mesh nodes of the attitude transformation part after simulation in step S323.

5. The pre-simulation adjustment method for posture transformation of a human finite element model according to claim 1, characterized in that: S33 includes: S331. Repair the mesh of the ligaments at the joint; S332. Perform a quality check on the human body model of the complete transformation pre-simulation.

6. The pre-simulation adjustment method for posture transformation of a human finite element model according to claim 1, characterized in that: In step S2, a preliminary transformation pre-simulation is performed on the limbs simultaneously; in step S3, a complete transformation pre-simulation is performed on the limbs simultaneously.

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