Intelligent cabin seat leg support rigidity CAE analysis method

Abstract

The invention discloses an intelligent cabin seat leg support rigidity and strength CAE analysis method, and relates to the technical field of automobile seat leg supports. Comprising the following steps: S10, establishing a three-dimensional mathematical model according to geometric parameters of a seat assembly, a leg support assembly and a pedal assembly; s20, building a finite element model of the seat assembly according to the three-dimensional mathematical models of the seat assembly, the leg support assembly and the pedal assembly; s30, endowing the built finite element models of the seat assembly, the leg support assembly and the pedal assembly with material attributes and physical characteristics, and establishing connection and contact among the seat assembly, the leg support assembly and the pedal assembly; s40, applying the loading force to the finite element models of the seat assembly, the leg support assembly and the pedal assembly, and collecting stress results of the seat assembly, the leg support assembly and the pedal assembly under the action of the loading force; and S50, the stress result is analyzed, and whether the rigidity and strength of the seat assembly, the leg support assembly and the pedal assembly meet the design target or not is determined. The beneficial effects of the invention are that the detection precision is high and the detection cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive seat leg rests, and particularly to an intelligent cockpit seat leg rest stiffness and strength CAE analysis method. Background Art

[0002] In order to relieve the soreness and discomfort caused by a single leg posture during long-term driving, many high-end automotive seats are equipped with a leg support function. In the case of limited interior space, to meet the requirements of ergonomics, the leg support function of automotive seats is generally realized by an electric or pneumatic system inside the seat structure. Under the action of the motor or pneumatic system, the leg rest support mechanism in the seat frame changes its position and angle according to the needs of the passengers, so as to support the calves of passengers in different positions and relieve the leg discomfort caused by a single sitting position.

[0003] The leg rest support mechanism usually includes a leg rest assembly and a footrest assembly. The leg rest assembly is connected to the seat frame. Under the action of the motor or pneumatic system, the leg rest assembly flips on the seat frame to support the calves of the passengers. The footrest assembly is installed on the leg rest assembly, and the footrest of the footrest assembly flips on the leg rest so that the feet of the passengers can rest on the footrest.

[0004] The leg rest support mechanism is used to carry the human legs, and it needs a certain structural stiffness and strength to provide stable support for the passengers. Therefore, before the product is applied, it is necessary to conduct a structural stiffness and strength test. However, it is difficult to accurately control various parameters in the stiffness and strength test of the actual product, and the test cost is relatively high. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an intelligent cockpit seat leg rest stiffness and strength CAE analysis method, which conducts a stiffness and strength test on the leg rest support mechanism through the CAE analysis method, with relatively high detection accuracy and relatively low detection cost.

[0006] The present invention provides an intelligent cockpit seat leg rest stiffness and strength CAE analysis method, including the following steps: S10. Establish a three-dimensional digital model according to the geometric parameters of the seat assembly, leg rest assembly, and footrest assembly; S20. Establish a finite element model of the seat assembly according to the three-dimensional digital model of the seat assembly, and establish finite element models of the leg rest assembly and the footrest assembly according to the three-dimensional digital models of the leg rest assembly and the footrest assembly; S30. Assign material properties and physical characteristics to the established finite element models of the seat assembly, leg rest assembly, and footrest assembly, and establish the connections and contacts between the seat assembly, leg rest assembly, and footrest assembly; S40. Apply the loading force required for testing to the finite element models of the seat assembly, leg rest assembly, and footrest assembly, and collect the force application results of the seat assembly, leg rest assembly, and footrest assembly under the loading force. S50. Analyze the force application results to confirm whether the stiffness and strength of the seat assembly, leg rest assembly, and footrest assembly meet the design objectives. If not, re-optimize the structural design of the seat assembly, leg rest assembly, and footrest assembly. If so, the analysis is completed.

[0007] Optionally, in step S20, the finite element model of the leg rest assembly includes the finite element model of the leg rest assembly in the folded state and the finite element model of the leg rest assembly in the unfolded state. The finite element model of the footrest assembly includes the finite element model of the footrest assembly in the folded state and the finite element model of the footrest assembly in the unfolded state. In step S40, the force application analysis is performed on the seat assembly, leg rest assembly, and footrest assembly in the two states respectively.

[0008] Optionally, in step S30, the connections of the finite element models of the leg rest assembly and the footrest assembly are established respectively, and the connections of the finite element model of the seat assembly, the finite element model of the leg rest assembly, and the finite element model of the footrest assembly are established. In step S40, the force application analysis is performed on two cases: the leg rest assembly and the footrest assembly are installed on the seat assembly, and the separate leg rest assembly and footrest assembly.

[0009] Optionally, when the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are in the folded state, the following steps are used for the force application analysis in step S40: S41. Establish a dummy model and place the dummy model on the seat assembly according to the hip point coordinates. S42. Input the collision acceleration curve to simulate the force application conditions of the leg rest assembly under the dynamic conditions of a frontal collision and an offset collision of the vehicle.

[0010] Optionally, when the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are in the unfolded state, the following steps are used for the force application analysis in step S40: S410. Establish a loading module and place the loading module on the leg rest assembly. S420. Use the loading module to apply a load to the leg rest assembly according to the set force value.

[0011] Optionally, in step S40, stress and strain information of the seat assembly, leg rest assembly, and footrest assembly are collected. In step S50, the position where the maximum strain occurs is confirmed, and the ratio of the strain value at this position to the initial length is compared with the elongation at break of the material at this position. If the ratio is less than the elongation at break of the material itself, it is determined that there is no risk of damage. If the ratio is greater than the elongation at break of the material itself, the structures of the seat assembly, leg rest assembly, and footrest assembly are optimized and returned to step S10.

[0012] Optionally, when separately performing a force test on the leg rest assembly and the footrest assembly, step S40 performs a force analysis using the following steps: S401. Establish a loading module and place the loading module on the leg rest assembly at the middle position of the connection between the leg rest assembly and the footrest assembly. S402. Establish another loading module and place the other loading module on the footrest of the footrest assembly at the middle position in the transverse direction of the footrest. S403. Use the two loading modules to apply loads with set force values to the leg rest assembly and the footrest assembly respectively.

[0013] Optionally, in step S40, the maximum displacement and permanent deformation of the leg rest assembly and the footrest assembly under the action of the load are collected. In step S50, it is determined whether the maximum displacement and permanent deformation of the leg rest assembly and the footrest assembly are within the preset standard range. If so, it is determined to be qualified. If not, the structures of the leg rest assembly and the footrest assembly are optimized and returned to step S10.

[0014] Optionally, in step S403, the loads applied by the two loading modules to the leg rest assembly and the footrest assembly are respectively perpendicular to the bearing surfaces of the leg rest of the leg rest assembly and the footrest of the footrest assembly.

[0015] Optionally, in step S10 when establishing the digital model, digital models of foaming materials are set on the bearing surfaces of the seat assembly and the leg rest assembly, and the densities of the digital models of the foaming materials on the seat assembly and the leg rest assembly are different.

[0016] The beneficial effects of the present invention are as follows: With the help of the CAE finite element analysis method, the present invention ensures that the simulation analysis process is consistent with the physical test method, and performs stiffness and strength detection on it through the CAE analysis method, which can reduce the detection cost while ensuring the detection accuracy. Description of the Drawings

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic flow diagram of a CAE analysis method for the stiffness and strength of the leg rest of an intelligent cockpit seat of the present invention.

[0019] Figure 2 It is a schematic diagram of the principle of equi-proportion magnification of a triangle.

[0020] Figure 3 It is a schematic diagram of assembling the finite element model of the leg rest assembly in the folded state onto the finite element model of the seat assembly and performing seat strength simulation analysis under the set collision condition of the whole seat finite element model with a dummy model.

[0021] Figure 4 It is a schematic diagram of assembling the finite element model of the leg rest assembly in the fully extended state onto the finite element model of the seat assembly and performing strength simulation analysis under the set static loading condition.

[0022] Figure 5 It is a schematic diagram of the rigidification treatment of the seat frame and the strength and stiffness analysis of the leg rest assembly.

[0023] Figure 6 It is a schematic diagram of the rigidification treatment of the seat frame and the strength and stiffness analysis of the footrest assembly. Specific embodiments

[0024] The following will describe specific embodiments of the present invention in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. Based on the description of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0025] Unless otherwise clearly specified and limited, terms such as "set", "installed", "connected", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific situations.

[0026] The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the inventive product is customarily placed during use. It is only for the convenience of description and to simplify the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present invention.

[0027] Terms such as "first", "second", "third", etc. are only used to distinguish elements with similar attributes, rather than indicating or implying relative importance or a specific order.

[0028] The term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion. In addition to the elements listed, it may also include other elements not specifically listed.

[0029] In the electric leg rest mechanism, the leg rest of the leg rest assembly is rotatably mounted on the seat frame of the seat assembly through a metal rotating shaft. An electric motor is used to drive a lead screw to drive a connecting rod to drive the leg rest to rotate on the seat frame, so as to adapt to the placement angle of the passenger's calf. The footrest of the footrest assembly is flip-connected to the leg rest through a gear, and is flipped to adapt to the position of the passenger's foot.

[0030] As Figure 1 shown, this embodiment provides a method for CAE analysis of the stiffness and strength of the leg rest of an intelligent cockpit seat, including the following steps: S10. Establish a three-dimensional digital model based on the geometric parameters of the seat assembly, leg rest assembly, and footrest assembly.

[0031] Step S10 specifically includes the following steps: S11. Establish a 3D digital model of the seat according to the 2D dimension parameters of the seat assembly; S12. Establish 3D digital models of the leg rest assembly and the footrest assembly according to the 2D dimension parameters of the leg rest assembly and the footrest assembly; S13. Use a simulation mechanism, such as the DMUKinematics mechanism (electronic prototype kinematics simulation), to adjust the leg rest in the folded state to the extreme open state.

[0032] It should be noted that the software used to establish the 3D digital model may include but is not limited to software such as CATIA, Pro / E, UG, etc.

[0033] Since foam materials are provided on the bearing surfaces of the seat assembly and the leg rest assembly, and the densities of the foam materials on the seat assembly and the leg rest assembly are different, and the foam materials have elasticity, when establishing the 3D digital models of the leg rest assembly and the seat assembly, it is necessary to consider the impact that the foam materials may have on the stiffness and strength of the leg rest assembly during the actual test; S20. Establish a finite element model of the seat assembly according to the three-dimensional digital model of the seat assembly, and establish a finite element model of the leg rest assembly and the footrest assembly according to the three-dimensional digital models of the leg rest assembly and the footrest assembly.

[0034] In step S20, establishing a finite element model according to the three-dimensional digital model of the seat assembly includes the following steps: S21. Import the three-dimensional digital model file (such as stp file) of the seat assembly into the pre-simulation processing software (such as Ansa); S22. Perform mid-surface extraction, geometric cleaning, and create finite element meshes for each component on the three-dimensional digital model of the seat assembly. Among them, tetrahedral meshes are drawn for the seat frame of the seat assembly, tetrahedral meshes are drawn for the foam material on the seat of the seat assembly, and hexahedral meshes are drawn for the metal rotating shaft that connects the seat assembly and the leg rest assembly and drives the leg rest assembly to flip; S23. Apply pre-tightening force treatment to the positions of the bolt holes on the seat frame through which the metal rotating shaft passes, and there should be no thickness interference. The magnitude of the pre-tightening force is half of the bolt proof load. The bolt proof load refers to the maximum tensile or shear force that the bolt can withstand under certain working conditions.

[0035] In step S20, establishing a finite element model according to the three-dimensional digital models of the leg rest assembly and the footrest assembly includes the following steps: S201. Import the three-dimensional digital model file (such as stp file) of the leg rest assembly and the footrest assembly in the folded state into the pre-simulation processing software (such as Ansa); S202. Perform mid-surface extraction, geometric cleaning, and create finite element meshes for each component on the three-dimensional digital models of the leg rest assembly and the footrest assembly. Among them, tetrahedral meshes are drawn for the frame of the leg rest assembly, hexahedral meshes are drawn for the motor connecting rod that drives the leg rest assembly to flip and the transmission gear that drives the footrest assembly to flip, and triangular meshes are drawn for the outer surface of the motor; S203. Use zero clearance simulation for the bolt holes at the position of the connecting rod that is connected to the motor and drives the leg rest assembly to flip, and the magnitude of the pre-tightening force at the motor bracket that supports the motor is half of the bolt proof load; S204. Import the three-dimensional digital model file (stp file) of the leg rest assembly and the footrest assembly in the unfolded state into the pre-simulation processing software (Ansa), use a conversion tool (such as the Transform tool) to perform point-to-point movement, adjust the three-dimensional digital models of the folded leg rest assembly and the footrest assembly to the extreme unfolded state, and save the model separately.

[0036] S30. Assign material properties and physical characteristics to the finite element models of the assembled seat assembly, leg rest assembly, and footrest assembly, and establish the connections and contacts between the seat assembly, leg rest assembly, and footrest assembly.

[0037] Step S30 specifically includes the following steps: S31. According to the bill of materials (BOM) of the seat assembly, assign the correct materials and physical characteristics to the finite element model of the seat assembly; S32. According to the BOMs of the leg rest assembly and the footrest assembly, assign the correct materials and physical characteristics to the finite element models of the leg rest assembly and the footrest assembly; S33. According to the differences in the foaming materials of the seat cushion of the seat assembly and the hardness of the foaming materials on the leg rest of the leg rest assembly, assign different densities to the foaming materials in different regions; S34. In order to accurately simulate the stress conditions of the motor link and the motor connection bracket under dynamic conditions, it is necessary to set material failure parameters for the motor link and the motor bracket; S35. Establish surface-to-surface contact, point-to-surface contact, self-contact, etc. between the finite element models of the seat assembly, leg rest assembly, and footrest assembly.

[0038] S40. Apply the loading force required for testing to the finite element models of the seat assembly, leg rest assembly, and footrest assembly. The loading force required for testing can act on the leg rest assembly or the footrest assembly. The magnitude and direction of the loading force can be adjusted according to the test requirements. After applying the loading force to the seat assembly, leg rest assembly, and footrest assembly, collect the stress results of the seat assembly, leg rest assembly, and footrest assembly under the action of the loading force.

[0039] S50. Analyze the stress results to confirm whether the stiffness and strength of the seat assembly, leg rest assembly, and footrest assembly meet the design objectives. If not, re-optimize the structural designs of the seat assembly, leg rest assembly, and footrest assembly. If they meet the requirements, the analysis is completed.

[0040] In the analysis method provided in this embodiment, the stress conditions and stress results of the leg rest support mechanism are simulated through the CAE analysis method to detect whether the stiffness and strength of the leg rest support mechanism meet the standards. If they meet the standards, it is determined to be qualified and production can be carried out. If the detection does not meet the standards, the structure is optimized and re-detected and analyzed, and the detection cost is relatively low.

[0041] Further, in step S20, the finite element models of the leg rest assembly and the footrest assembly respectively include the finite element models of the leg rest assembly and the footrest assembly in the folded state and the finite element models of the leg rest assembly and the footrest assembly in the unfolded state. In step S40, the force analysis is performed on the seat assembly, the leg rest assembly, and the footrest assembly in both states. The leg rest assembly and the footrest assembly have two states of folding and unfolding during actual use. The force detection is respectively performed on the leg rest assembly and the footrest assembly in the folded and unfolded states, and the detection is more comprehensive, meeting the requirements of actual detection.

[0042] When the leg rest assembly is installed on the seat frame of the seat assembly for test analysis, the seat frame is considered as a deformable body according to the actual situation. According to E = 1 / 2MV^2, on the premise that the total energy is constant, when the leg rest assembly is stressed, it will drive the seat frame to deform. Due to the deformation of the seat frame itself, part of the energy is absorbed by the seat frame. The strength analysis result of the leg rest assembly is good, but the displacement inspection condition is harsh. For example, Figure 2 As shown, according to the principle of equal proportion amplification of the triangle, the small deviation of the gap of the connecting pipe connecting the leg rest assembly on the seat frame and the deformation of the seat frame will cause a large displacement of the leg rest assembly. This method cannot accurately detect the rigidity and strength of the leg rest assembly itself.

[0043] Therefore, in step S30, the finite element models of the leg rest assembly and the footrest assembly installed on the seat assembly and the finite element models of the leg rest assembly and the footrest assembly not installed on the seat assembly are respectively established for the seat assembly, the leg rest assembly, and the footrest assembly. In step S40, the force analysis is respectively performed on the two cases of the leg rest assembly and the footrest assembly installed on the seat assembly and the separate leg rest assembly and footrest assembly. By detecting the rigidity and strength of the leg rest assembly and the footrest assembly installed on the seat assembly and the separate leg rest assembly and footrest assembly, the accuracy of the detection result can be ensured.

[0044] Specifically, as Figure 3 shown, when the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are in the folded state, the connection and contact are established between the leg rest of the leg rest assembly and the seat frame of the seat assembly according to the actual situation, and the surface-to-surface contact is established between the leg rest and the support surface of the vehicle floor. In step S40, the following steps are used for force analysis: S41. Establish a dummy model, place the dummy model on the seat assembly according to the H-point (Hip Point, which refers to the connection point of the human torso and thigh in the two-dimensional or three-dimensional human model template, i.e., the hip point. In the human template, it is the hip joint, which represents the position of the midpoint of the hip joint of the driver after taking a seat in the vehicle) coordinates, keep the dummy's head horizontal, clamp the upper arms against the seat backrest, and place the feet horizontally on the support surface of the vehicle floor; arrange the position of the seat belt according to the actual situation.

[0045] S42. Input the collision acceleration curve to simulate the force on the leg rest assembly under the dynamic conditions of a frontal collision and an offset collision of the vehicle. This step simulates the deformation of the leg rest assembly under the action of dynamic inertial force when the vehicle has a car accident or sudden braking resulting in a sharp reduction in speed, and detects the strength of the leg rest assembly under the action of dynamic inertial force.

[0046] As Figure 4 shown, when the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are in the deployed state, install the leg rest of the deployed leg rest assembly on the seat frame of the seat assembly, establish connections and contacts between the leg rest and the seat frame according to the actual situation, establish surface-to-surface contact between the leg rest and the vehicle floor support surface, and the following steps are adopted for force analysis in step S40: S410. Establish a sphere as the loading module, place the loading module on the leg rest assembly, and limit the loading module at the corner connection of the leg rest assembly and the footrest assembly; S420. The loading module loads the leg rest assembly according to the set force value, and after the loading is completed, collect the deformation of the leg rest assembly in the transverse and vertical directions.

[0047] In step S40, use engineering simulation post-processing software (such as Hyper View) to open the result file (such as d3plot), and view the stress and strain contour maps of the seat frame and the leg rest assembly according to the collected stress and strain information of the seat assembly, the leg rest assembly, and the footrest assembly. In step S50, confirm the position where the maximum strain occurs according to the stress and strain contour map, compare the ratio of the strain value at this position to the initial length with the elongation at break of the material at this position. If the ratio is less than the elongation at break of the material itself, it is determined that there is no risk of damage. If the ratio is greater than the elongation at break of the material itself, optimize the structures of the seat assembly, the leg rest assembly, and the footrest assembly, and return to step S10.

[0048] By installing the leg rest assembly and the footrest assembly on the seat assembly as a whole and conducting dynamic and static detection and analysis respectively, the simulation accuracy can be improved and the accuracy of the detection and analysis can be guaranteed.

[0049] When conducting a force test on the leg rest assembly and the footrest assembly separately, fix the deployed leg rest assembly on the square tube connecting the seat frame and the leg rest. The material of the square tube is set to MAT20 (steel body). At this time, the seat assembly is used as a rigid body and will not deform, which will not affect the test and analysis results of the leg rest assembly and the footrest assembly. The following steps are adopted for force analysis in step S40: S401. As Figure 5As shown, a spherical ball with a diameter of 102 mm is established as the loading module. The loading module is placed on the leg rest assembly at the middle position of the connection between the leg rest assembly and the footrest assembly, and the load exerted by the loading module on the leg rest assembly is perpendicular to the bearing surface of the leg rest of the leg rest assembly; S402. As Figure 6 shown, a spherical ball with a diameter of 102 mm is established as another loading module. The loading module is placed on the footrest of the footrest assembly at the middle position in the transverse direction of the footrest, and the load exerted by the loading module on the footrest assembly is perpendicular to the bearing surface of the footrest of the footrest assembly. The 102 mm of the spherical ball is only the size set in this embodiment. Spherical balls with different diameters can be selected according to the needs of seat assemblies, leg rest assemblies, and footrest assemblies with different sizes; S403. The two loading modules apply loads with set force values of 1068 N and 1200 N to the leg rest assembly and the footrest assembly respectively. Collect the maximum displacement and permanent deformation of the leg rest assembly and the footrest assembly under the action of the load. The maximum displacement includes elastic deformation and permanent deformation. The leg rest assembly and the footrest assembly can elastically recover after displacement, while permanent deformation cannot be recovered. The loads of 1068 N and 1200 N are the force values selected in this embodiment. Loads with different force values can be selected according to the needs of seat assemblies, leg rest assemblies, and footrest assemblies with different sizes.

[0050] In step S50, it is determined whether the maximum displacement and permanent deformation of the leg rest assembly and the footrest assembly are within the preset standard range. If so, it is determined to be qualified; if not, the structures of the leg rest assembly and the footrest assembly are optimized and returned to step S10. For example, when the leg rest assembly is under the action of a 1068 N force value, the permanent deformation is required to be less than 25.4 mm. When the footrest assembly is under the action of a 1200 N force value, the permanent deformation is required to be less than 5 mm, otherwise it is unqualified.

[0051] In summary, the intelligent cockpit seat leg rest stiffness and strength CAE analysis method provided in this embodiment combines dynamic, static, and separate tests of the leg rest assembly installed on the seat assembly and the leg rest assembly. Among these methods, one method can be selected for detection and analysis, or all three situations can be detected and analyzed. Only when all three situations meet the requirements is it considered qualified for detection. Such a method can accurately test and analyze the stiffness and strength of the leg rest assembly and the footrest assembly, and reduce the detection cost.

[0052] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A CAE analysis method for the rigidity of leg support of intelligent cockpit seat, characterized in that: The following steps are involved: S10. Establish a three-dimensional digital model based on the geometric parameters of the seat assembly, the leg rest assembly and the pedal assembly; S20. Establishing a finite element model of the seat assembly according to the three-dimensional digital model of the seat assembly, and establishing a finite element model of the leg rest assembly and the pedal assembly according to the three-dimensional digital model of the leg rest assembly and the pedal assembly; S30. Assigning material properties and physical properties to the finite element model of the built seat assembly, the leg rest assembly and the pedal assembly, and establishing connection and contact between the seat assembly, the leg rest assembly and the pedal assembly; S40. According to the loading force required for the test, the finite element model of the seat assembly, the leg rest assembly and the pedal assembly is applied, and the force results of the seat assembly, the leg rest assembly and the pedal assembly under the loading force are collected; S50. Analyze the force results to confirm whether the rigidity of the seat assembly, the leg rest assembly and the footrest assembly meets the design target. If not, re-optimize the structural design of the seat assembly, the leg rest assembly and the footrest assembly. If so, the analysis is completed.

2. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 1 is characterized in that: In the step S20, the finite element model of the leg rest assembly includes a finite element model of the leg rest assembly in a folded state and a finite element model of the leg rest assembly in an unfolded state, the finite element model of the footrest assembly includes a finite element model of the footrest assembly in a folded state and a finite element model of the footrest assembly in an unfolded state, and in the step S40, force analysis is performed on the seat assembly, the leg rest assembly and the footrest assembly in the two states respectively.

3. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 2 is characterized by: In the step S30, the connection between the finite element models of the leg rest assembly and the footrest assembly and the connection between the finite element model of the seat assembly, the finite element model of the leg rest assembly and the finite element model of the footrest assembly are respectively established. In the step S40, force analysis is performed on the two situations where the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are installed separately.

4. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 3 is characterized by: When the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are in a folded state, the force analysis is performed in step S40 using the following steps: S41. Establish a dummy model and place the dummy model on the seat assembly according to the coordinates of the hip point; S42. Input the collision acceleration curve to simulate the stress condition of the leg support assembly under the dynamic working conditions of head-on collision and offset collision of the vehicle.

5. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 3 is characterized by: When the leg rest assembly and the footrest assembly are installed on the seat assembly and the leg rest assembly and the footrest assembly are in the unfolded state, the force analysis is performed in the step S40 using the following steps: S410 establishes a loading module, and places the loading module on the leg rest assembly; S420. Use the loading module to apply a load to the leg support assembly according to the set force value.

6. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 4 or 5, characterized in that: In the step S40, the stress and strain information of the seat assembly, the leg rest assembly and the footrest assembly are collected. In the step S50, the position where the maximum strain occurs is confirmed, and the ratio of the strain value and the initial length at the position is compared with the elongation at break of the material at the position. If the ratio is smaller than the elongation at break of the material itself, it is determined that there is no risk of damage. If the ratio is larger than the elongation at break of the material itself, the seat assembly, the leg rest assembly and the footrest assembly are structurally optimized and the process returns to the step S10.

7. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 3 is characterized by: When the force test is performed on the leg rest assembly and the pedal assembly separately, the step S40 performs the force analysis using the following steps: S401 establishes a loading module, the loading module is placed on the leg rest assembly and located in the middle of the connection between the leg rest assembly and the pedal assembly; S402 establishes another loading module, and the other loading module is placed on the pedal of the pedal assembly and is located in the middle of the pedal lateral position; S403. Use two loading modules to apply loads of set force values ​​to the leg support assembly and the pedal assembly respectively.

8. The CAE analysis method for the rigidity of the leg support of an intelligent cockpit seat according to claim 7, characterized in that: In the step S40, the maximum displacement and permanent deformation of the leg rest assembly and the foot pedal assembly under load are collected. In the step S50, it is determined whether the maximum displacement and permanent deformation of the leg rest assembly and the foot pedal assembly are within a preset standard range. If so, it is determined to be qualified. If not, the structure of the leg rest assembly and the foot pedal assembly is optimized and the process is returned to the step S10.

9. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 7, characterized in that: In step S403, the loads applied by the two loading modules to the leg rest assembly and the pedal assembly are respectively perpendicular to the bearing surface of the leg rest of the leg rest assembly and the bearing surface of the pedal of the pedal assembly.

10. The CAE analysis method for the rigidity of the leg support of the intelligent cockpit seat according to claim 1, characterized in that: In the step S10 of establishing the digital model, the digital models of the foam material are arranged on the bearing surfaces of the seat assembly and the leg rest assembly, and the density of the digital models of the foam material on the seat assembly and the leg rest assembly is different.

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