Seat simulation method and device based on body pressure distribution, seat and vehicle

Abstract

The invention provides a seat simulation method and device based on body pressure distribution, a seat and a vehicle. The method comprises the steps that a human body finite element model, a first seat finite element model and a second seat finite element model are established; assembling the human body finite element model and the first seat finite element model to obtain a first seat simulation model; assembling the human body finite element model and the second seat finite element model to obtain a second seat simulation model; carrying out a load test on the first seat simulation model to obtain a first group of body pressure distribution data; carrying out a load test on the second seat simulation model to obtain a second group of body pressure distribution data; the comfort of the seat is verified based on the first set of body pressure distribution data and the second set of body pressure distribution data. According to the technical scheme, waste of time and research and development resources can be reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of vehicle seats, and in particular to a seat simulation method and device based on body pressure distribution, a seat, and a vehicle. Background Art

[0002] With the continuous development of the automotive industry, the requirements for automobile safety are getting higher and higher, which often requires people to compromise on seat comfort to ensure safety.

[0003] In the traditional automotive design process, the seat development phase involves the development and refinement of multiple prototypes, a process largely performed manually. After the seat is built, a metal mannequin is fabricated and mounted on the seat to simulate a real person sitting in the seat. This data is then used to obtain body pressure distribution data, which is then used to adjust the seat parameters.

[0004] The above R&D process results in a huge waste of time and R&D resources. Summary of the Invention

[0005] In order to solve the above technical problems, the present disclosure provides a seat simulation method, device, seat and vehicle based on body pressure distribution to reduce the waste of time and R&D resources.

[0006] A first aspect of the present disclosure provides a seat simulation method based on body pressure distribution, including: establishing a human body finite element model, a first seat finite element model and a second seat finite element model; assembling the human body finite element model with the first seat finite element model to obtain a first seat simulation model; assembling the human body finite element model with the second seat finite element model to obtain a second seat simulation model; performing a load test on the first seat simulation model to obtain a first set of body pressure distribution data; performing a load test on the second seat simulation model to obtain a second set of body pressure distribution data; and verifying the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data.

[0007] In one possible implementation, establishing a human finite element model includes: obtaining the ankle position and hip position of the human body when the human body finite element model is in a sitting position; adjusting the ankle position according to a set step length to adjust the relative distance between the ankle position and the hip position, thereby obtaining human body finite element models in different postures.

[0008] In one possible implementation, establishing a finite element model of the human body further includes: acquiring human body dimension data and human body three-dimensional data, wherein the human body three-dimensional data includes human body point cloud data and / or human body slice data; constructing a skeletal geometric model based on the human body dimension data; and matching the skeletal geometric model to the human body three-dimensional data to obtain a finite element model of the human body.

[0009] In one possible implementation, the first seat finite element model includes a first surface shell model and a first frame body model, wherein the first frame body model includes a first anti-diving tube model; the second seat finite element model includes a second surface shell model and a second frame body model, wherein the second frame body model includes a second anti-diving tube model, and the distance between the first surface shell model and the first anti-diving tube model is smaller than the distance between the second surface shell model and the second anti-diving tube model, wherein the first surface shell model and the second surface shell model are in the same plane.

[0010] In one possible implementation, the first skeleton model includes a first seat cushion suspension model, the second skeleton model includes a second seat cushion suspension model, a first anti-diving slope is formed between the first seat cushion suspension model and the first anti-diving tube model, and a second anti-diving slope is formed between the second seat cushion suspension model and the second anti-diving tube model, and the angle between the first anti-diving slope and the first plane is greater than the angle between the second anti-diving slope and the first plane.

[0011] In one possible implementation, the first seat finite element model also includes: a first sponge body model built by the first sponge parameters, and a first suspension body model built by the first suspension parameters; the second seat finite element model also includes: a second sponge body model built by the second sponge parameters, and a second suspension body model built by the second suspension parameters, wherein the first sponge parameters are the same as the second sponge parameters, and the first suspension parameters are the same as the second suspension parameters.

[0012] In one possible implementation, assembling the human body finite element model with the first seat finite element model to obtain the first seat simulation model includes: setting a first constraint condition on the first seat finite element model;

[0013] A second constraint condition is set between the contact surface of the human body finite element model and the first seat finite element model, and the human body finite element model and the second seat finite element model are assembled to obtain a second seat simulation model, including: setting a first constraint condition on the second seat finite element model; setting a second constraint condition between the contact surface of the human body finite element model and the second seat finite element model; wherein the first constraint condition is used to constrain the six directional degrees of freedom of the seat; the second constraint condition includes a tangential constraint condition and a normal constraint condition, the tangential constraint condition is set using a penalty function, and the normal constraint condition is set using a penalty function constraint enhancement setting.

[0014] In one possible implementation, the first body pressure distribution data includes a peak pressure at the first ischial tuberosity, an average pressure at the first ischial tuberosity, a peak pressure at the first backrest, and an average pressure at the first backrest; the second body pressure distribution data includes a peak pressure at the second ischial tuberosity, an average pressure at the second ischial tuberosity, a peak pressure at the second backrest, and an average pressure at the second backrest; and verifying the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data includes: when the first set of body pressure distribution data and the first set of body pressure distribution data meet preset conditions, determining that the seat comfort corresponding to the second seat finite element model is better than the seat comfort corresponding to the first seat finite element model; wherein the preset conditions include: the peak pressure at the second ischial tuberosity is smaller than the peak pressure at the first ischial tuberosity; the amplitude of the change from the average pressure at the first ischial tuberosity to the average pressure at the second ischial tuberosity is smaller than a first preset value; the amplitude of the change from the peak pressure at the first backrest to the peak pressure at the second backrest is smaller than a second preset value; and the amplitude of the change from the average pressure at the first backrest to the average pressure at the second backrest is smaller than a third preset value.

[0015] The second aspect of the present disclosure provides a seat simulation device based on body pressure distribution, including: a finite element model establishment module, which establishes a human body finite element model, a first seat finite element model and a second seat finite element model; a first simulation model assembly module, which is used to assemble the human body finite element model with the first seat finite element model to obtain a first seat simulation model; a second simulation model assembly module, which is used to assemble the human body finite element model with the second seat finite element model to obtain a second seat simulation model; a first load test module, which is used to perform a load test on the first seat simulation model to obtain a first set of body pressure distribution data; a second load test module, which is used to perform a load test on the second seat simulation model to obtain a second set of body pressure distribution data; and a comfort verification module, which is used to verify the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data.

[0016] A third aspect of the present disclosure provides a seat, which is manufactured by processing structural parameters obtained by simulation according to the seat simulation method based on body pressure distribution as described above.

[0017] A fourth aspect of the present disclosure provides a vehicle comprising the seat according to the third aspect.

[0018] The technical solution provided by the present disclosure has the following advantages compared with the existing technology:

[0019] The present disclosure provides a seat simulation method, device, seat, and vehicle based on body pressure distribution. The method comprises: establishing a human body finite element model, a first seat finite element model, and a second seat finite element model; assembling the human body finite element model with the first seat finite element model to obtain a first seat simulation model; assembling the human body finite element model with the second seat finite element model to obtain a second seat simulation model; performing a load test on the first seat simulation model to obtain a first set of body pressure distribution data; performing a load test on the second seat simulation model to obtain a second set of body pressure distribution data; and verifying the comfort of the seat based on the first and second sets of body pressure distribution data. The seat simulation method based on body pressure distribution is implemented by establishing a human body finite element model and a seat finite element model, performing finite element analysis on the process of a person sitting on the seat using a finite element analysis method to obtain body pressure distribution data, and then verifying the comfort of the seat based on the body pressure distribution data obtained using the finite element analysis method. Because seat verification is achieved through finite element analysis, there is no need to produce multiple prototype seats and metal human body models, nor is there a need to mount a metal human body model on the seat to simulate the process of a real person sitting on the seat, thereby reducing the waste of time and R&D resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0021] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0022] Figure 1 This is a flowchart of a seat simulation method based on body pressure distribution in an embodiment of the present disclosure;

[0023] Figure 2 This is a schematic diagram of a simulation model of a human body in a normal sitting posture in an embodiment of the present disclosure;

[0024] Figure 3 This is a schematic diagram of a simulation model of a human body in a reclining sitting position in an embodiment of the present disclosure;

[0025] Figure 4 This is a schematic structural diagram of a seat frame in an embodiment of the present disclosure;

[0026] Figure 5 This is a model assembly diagram of a human body and a seat in one embodiment of the present disclosure;

[0027] Figure 6 This is a schematic diagram of body pressure distribution of a seat when a human body is in a normal sitting position in an embodiment of the present disclosure;

[0028] Figure 7 This is a schematic diagram of body pressure distribution of a seat after adjustment when a human body is in a normal sitting posture in one embodiment of the present disclosure;

[0029] Figure 8 This is a simulation model diagram of a human body in a lying down sitting position in an embodiment of the present disclosure;

[0030] Figure 9 This is a schematic diagram of body pressure distribution of a seat when a person is in a lying-flat sitting position in an embodiment of the present disclosure;

[0031] Figure 10 Schematic diagram of the structure of a seat simulation device based on body pressure distribution in an embodiment of the present disclosure;

[0032] Figure 11 An exploded view of a seat frame in an embodiment of the present disclosure;

[0033] Figure 12 This is a structural diagram of a seat in an embodiment of the present disclosure;

[0034] Figure 13 This is a side structural diagram of a seat in one embodiment of the present disclosure.

[0035] Reference numerals:

[0036] 10. Seat; 11. Anti-dive tube; 12. Seat rear crossbar; 13. Seat bowl bracket; 14. Seat side panels; 15. Seat cover; 16. Seat suspension; 17. Anti-dive slope. DETAILED DESCRIPTION

[0037] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features therein can be combined with each other in the absence of conflict.

[0038] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0039] Figure 1This is a flowchart of a seat simulation method based on body pressure distribution in an embodiment of the present disclosure. This embodiment is applicable to situations where comparative analysis of seat comfort is performed. The method can be executed by a seat simulation device based on body pressure distribution. The seat simulation device based on body pressure distribution can be implemented in software and / or hardware. The seat simulation method based on body pressure distribution can be executed by a user terminal or a server.

[0040] like Figure 1 As shown, the seat simulation method based on body pressure distribution provided by the embodiment of the present disclosure mainly includes steps S101-S104.

[0041] In the embodiment of the present disclosure, a computer aided engineering (CAE) analysis method is used to simulate and analyze the process of a person sitting on a car seat, thereby obtaining body pressure distribution data formed on the car seat after the person sits on the car seat, and then analyzing and judging the comfort of the car seat based on the body pressure distribution data.

[0042] CAE analysis method is an approximate numerical analysis method that uses computers to assist in solving problems such as the analysis and calculation of mechanical properties such as strength, stiffness, buckling stability, dynamic response, heat conduction, three-dimensional multi-body contact, elastic-plasticity, etc. of complex engineering and product structures, as well as the optimization design of structural performance.

[0043] S101. Establish a human body finite element model, a first seat finite element model, and a second seat finite element model.

[0044] A human finite element model is a simulation model of the human body built in CAE software based on human-related data. Human-related data primarily includes body dimensional data and 3D data. Dimensional data describes physical characteristics of the human body, such as height, weight, and sitting height. 3D data primarily includes point cloud data and / or slice data. Point cloud data refers to human data represented in point cloud form, while slice data refers to human data represented in slice form.

[0045] The human body finite element model includes human body models in different postures. Further, the human body finite element model includes human body models in different sitting postures. Specifically, the human body finite element model includes a human body model in a normal sitting posture and a human body model in a reclining sitting posture. Figure 2 As shown, the human body model in the reclining sitting position is as follows Figure 3 shown.

[0046] The following briefly describes the method for establishing a human finite element model. Specifically, establishing a human finite element model also includes: obtaining human body dimensional data and three-dimensional human body data, where the three-dimensional human body data includes human body point cloud data and / or human body slice data; constructing a skeletal geometry model based on the human body dimensional data; and matching the skeletal geometry model to the three-dimensional human body data to obtain a human finite element model.

[0047] Based on height, sitting height, and weight, a human body dimension prediction model is used to calculate human body dimensions. A human skeletal model is then constructed using geometric scaling. The skeletal geometric model is then matched to the 3D human body data using reference to human surface point cloud data and human slice data to create a human body geometric model. The posture model is then used to predict and set the posture of the human body geometric model. A finite element model is then constructed based on the human body geometric model. This involves covering the surface of the human geometric model with skin and adding soft tissue between the skin and the skeleton to create a finite element model.

[0048] In one embodiment, the human body geometry model is adjusted to a normal sitting posture using the posture model, and the following is obtained: Figure 2 The finite element model of the human body in a normal sitting position is shown.

[0049] In another embodiment, when the human body finite element model is in a sitting position, the ankle position and the hip point position of the human body are obtained; the ankle position is adjusted according to the set step length to adjust the relative distance between the ankle position and the hip point position, thereby obtaining human body finite element models in different postures.

[0050] In order to analyze the body pressure distribution of different human sitting postures, the ankle position relative to the hip point is parameterized, and a calculation step length (Step) is set. This step length is used to adjust the position of the ankle relative to the hip point, thereby achieving different postures of the lower limbs.

[0051] Specifically, when a person sits on a car seat, the hip point position remains basically unchanged. Therefore, the ankle position can be adjusted according to the step length, thereby realizing the relative distance between the ankle position and the hip point position, and obtaining a finite element model of the human body with the lower limbs in different postures.

[0052] In this way, the body pressure distribution data of the car seat under different human sitting postures can be analyzed, and then the comfort of the seat under different human postures can be analyzed and judged.

[0053] Next, the finite element model of the seat is described.

[0054] A seat finite element model is a simulation model of an automotive seat built in CAE software based on seat-related parameters, including seat trim parameters, seat frame parameters, seat suspension parameters, and seat foam parameters. The first and second seat finite element models have different seat frame parameters, but the seat trim parameters, seat suspension parameters, and seat foam parameters are the same.

[0055] In this way, two seat finite element models with different skeleton parameters can be simulated, and then two sets of body pressure distribution data formed by the same human body finite element model on different seat finite element models can be analyzed, and the comfort of the two seats can be judged based on the two sets of body pressure distribution data.

[0056] It should be noted that the construction method of the first seat finite element model and the construction method of the second seat finite element model are only different in the parameters of the seat frame.

[0057] The method for constructing a finite element model of a seat includes: establishing a face cover shell model based on face cover parameters, establishing a comfort sponge model based on comfort sponge parameters, establishing a main sponge model based on main sponge parameters, establishing a suspension model based on suspension parameters, and establishing a skeleton model based on skeleton parameters. Based on the positional relationship between the face cover, comfort sponge, main sponge, suspension and skeleton, the face cover shell model, comfort sponge model, main sponge model, suspension model and skeleton model are assembled to obtain a finite element model of the seat. For example: wrap the face cover shell model on the outside of the comfort sponge model, attach the comfort sponge model to the outside of the main sponge model, and cover the main sponge model on the outside of the skeleton model and the suspension model. Furthermore, since many details of the seat contain many irregular shapes, they are automatically meshed. All other components except the above-mentioned component models are filled with meshes.

[0058] Furthermore, a pulling force is applied to the seams of the face cover toward the sponge to tighten the face cover.

[0059] Meshing the seat finite element model. Meshing is used to divide the second finite element model into many small elements. As a crucial pre-processing step for finite element analysis, the degree to which the meshing matches the calculation objectives, as well as the quality of the mesh, determines the quality of the subsequent finite element calculations. When meshing the seat, the seat cushion cover is meshed using shell elements, while the remaining elements are meshed using solid elements. Because many details on the seat contain irregular shapes, automatic meshing is used for all irregularly shaped parts.

[0060] When a vehicle is involved in a head-on collision, passengers are pulled forward by inertia. Constrained by the seatbelt, they tend to slide forward and downward, causing the lap belt to dig into the soft abdominal tissues (called "dive"). During a dive, the lap belt portion of the seatbelt can cause significant damage to the passenger's pelvis, abdomen, and even chest. Vehicle seats are typically designed with anti-dive features to ensure passenger safety.

[0061] Anti-submarine structure reference Figure 4 As shown, the seat cushion cover 15 is mounted on the outside of the seat frame. The seat frame includes a seat cushion suspension 16 and an anti-diving tube 11 located above the seat cushion suspension 16. The portion of the seat cushion suspension 16 close to the anti-diving tube 11 is extended obliquely upward in the direction close to the anti-diving tube 11 to form an anti-diving slope 17 to prevent passengers from sliding forward and downward and diving when the vehicle collides.

[0062] In one possible implementation, the first seat finite element model includes a first surface shell model and a first frame body model, wherein the first frame body model includes a first anti-diving tube model; the second seat finite element model includes a second surface shell model and a second frame body model, wherein the second frame body model includes a second anti-diving tube model, and the distance between the first surface shell model and the first anti-diving tube model is smaller than the distance between the second surface shell model and the second anti-diving tube model, wherein the first surface shell model and the second surface shell model are in the same plane.

[0063] In one possible implementation, the first skeleton model includes a first seat cushion suspension model, the second skeleton model includes a second seat cushion suspension model, a first anti-dive slope is formed between the first seat cushion suspension model and the first anti-dive tube model, and a second anti-dive slope is formed between the second seat cushion suspension model and the second anti-dive tube model, and the angle between the first anti-dive slope and the first plane is greater than the angle between the second anti-dive slope and the first plane.

[0064] In one possible implementation, the first seat finite element model also includes: a first sponge body model constructed by first sponge parameters, and a first suspension body model constructed by first suspension parameters; the second seat finite element model also includes: a second sponge body model constructed by second sponge parameters, and a second suspension body model constructed by second suspension parameters, wherein the first sponge parameters are the same as the second sponge parameters, and the first suspension parameters are the same as the second suspension parameters.

[0065] The finite element model of the seat includes a seat frame model, which includes an anti-diving tube, a rear cross bar of the seat cushion, a seat basin bracket and two seat side panels. The two seat side panels are extended relative to each other, and the anti-diving tube and the rear cross bar of the seat cushion are arranged relative to each other and are respectively connected between the two seat side panels. The anti-diving tube is located at one end of the seat side panel away from the backrest, and the rear cross bar of the seat cushion is located at the other end of the seat side panel, that is, the end of the rear cross bar of the seat cushion close to the backrest. Welding holes are formed at both ends of the seat side panel. The anti-diving tube is set higher than the rear cross bar of the seat cushion. The seat basin bracket is located between the two seat side panels and overlaps with the anti-diving tube, and the seat basin bracket is extended upward as a whole to provide front-end support for the seat cushion cover.

[0066] The seat frame model also includes a seat cushion suspension, which extends along the seat side panels. During assembly, the anti-submergence tube and the rear crossbar are first inserted into the welding holes at both ends of the two seat side panels 14 and welded securely. Then, the seat basin bracket is overlapped and welded to the anti-submergence tube. One end of the seat cushion suspension is overlapped and fixed to the seat basin bracket, and the other end is overlapped and fixed to the rear crossbar. The two ends of the seat cushion suspension can be fixedly connected by welding.

[0067] The seat finite element model also includes a trim model, which fits over the seat frame model. The trim can be made of elastic materials such as fabric, artificial leather, and natural leather. The seat filling can be made of various foam materials, gas, or liquid fillers.

[0068] In the first seat finite element model, the distance between the outer surface of the seat basin area and the anti-diving tube 11 is h = 63.9 mm. In the second seat finite element model, the distance between the outer surface of the seat basin area and the anti-diving tube 11 is h ≥ 70 mm. Optionally, the distance between the outer surface of the seat basin area and the anti-diving tube 11 is 73.9. In the first seat finite element model, the Z-axis step difference angle a of the longitudinal support beam of the seat cushion frame is 44°. In the second seat finite element model, the Z-axis step difference angle a of the longitudinal support beam of the seat cushion frame is 37°.

[0069] In actual application, the distance between the outer surface of the seat cushion cover and the anti-diving tube and the angle between the anti-diving slope and the horizontal plane can be adjusted at the same time, thereby achieving the pursuit of seat comfort while ensuring safety. Figure 8 As shown in the figure, when a vehicle collides, the displacement is required to meet the technical requirements of X < 190mm and Z < 50mm; where X is the forward displacement of the human body and Z is the downward displacement of the human body. Figure 8 The H point is the hip point, which is the rotation point where the torso and thigh are connected. The H' point is the position of the hip point after the human body is displaced after a vehicle collision.

[0070] S102 , assembling the human body finite element model and the first seat finite element model to obtain a first seat simulation model; assembling the human body finite element model and the second seat finite element model to obtain a second seat simulation model.

[0071] The assembling method of the human body finite element model and the first seat finite element model is the same as the assembling method of the human body finite element model and the second seat finite element model.

[0072] The human body finite element model is assembled with the first seat finite element model to obtain a first seat simulation model, including: setting a first constraint condition on the first seat finite element model; setting a second constraint condition between the contact surface of the human body finite element model and the first seat finite element model. The human body finite element model is assembled with the second seat finite element model to obtain a second seat simulation model, including: setting a first constraint condition on the second seat finite element model; setting a second constraint condition between the contact surface of the human body finite element model and the second seat finite element model; wherein the first constraint condition is used to constrain the six degrees of freedom of the seat; the second constraint condition includes a tangential constraint condition and a normal constraint condition, the tangential constraint condition is set using a penalty function, and the normal constraint condition is set using a penalty function constraint enhancement setting.

[0073] The tangential properties between the human body and the seat interface are set using a penalty function, with a friction coefficient of 0.3 (varies depending on the cover material). The relationship between contact pressure and penetration is defined using normal properties, typically using a penalty function constraint enhancement method. To ensure the seat remains motionless during simulation, the skeleton's six degrees of freedom must be constrained.

[0074] S103 . Perform a load test on the first seat simulation model to obtain a first set of body pressure distribution data; perform a load test on the second seat simulation model to obtain a second set of body pressure distribution data.

[0075] After the human body model is built, it needs to be assembled with the seat. First, the human body model is displaced relative to the seat, such as Figure 5 During the simulation, a vertical gravity field is applied to make the human body fall normally and complete the sitting process.

[0076] S104: Verify the comfort of the seat based on the first set of body pressure distribution data and the second set of body pressure distribution data.

[0077] In one possible implementation, the first body pressure distribution data includes a pressure peak at the first ischial tuberosity, an average pressure at the first ischial tuberosity, a pressure peak at the first backrest, and an average pressure at the first backrest; the second body pressure distribution data includes a pressure peak at the second ischial tuberosity, an average pressure at the second ischial tuberosity, a pressure peak at the second backrest, and an average pressure at the second backrest; and verifying the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data includes: when the first set of body pressure distribution data and the first set of body pressure distribution data meet preset conditions, , determine that the seat comfort corresponding to the second seat finite element model is better than the seat comfort corresponding to the first seat finite element model; wherein, the preset conditions include: the peak pressure at the second ischial tuberosity is smaller than the peak pressure at the first ischial tuberosity; the amplitude of the change from the average pressure at the first ischial tuberosity to the average pressure at the second ischial tuberosity is smaller than a first preset value; the amplitude of the change from the peak pressure at the first backrest to the peak pressure at the second backrest is smaller than a second preset value; the amplitude of the change from the average pressure at the first backrest to the average pressure at the second backrest is smaller than a third preset value.

[0078] The first body pressure distribution data and the peak and average pressure values at the ischial tuberosity in the first body pressure distribution data are compared, as are the peak and average pressure values at the backrest in the first body pressure distribution data. The seat comfort level is determined based on these two sets of peak and average pressure values. The pressure values are negatively correlated with the seat comfort level. In other words, by comparing the peak and average pressure values of the two seat contact surfaces, the seat comfort level can be determined based on the pressure values. A higher seat contact surface pressure indicates a lower seat comfort level, while a lower seat contact surface pressure indicates a higher seat comfort level.

[0079] In a possible implementation, when the human body finite element model is in a normal sitting position, the human body's buttocks and ischial tuberosity exert a greater gravity on the horizontal contact surface of the seat, so the comparison is made between the peak pressure value and the average pressure value at the ischial tuberosity in the initial state and the adjusted state of the seat. Figure 6 and Figure 7As shown in the figure, the peak pressure of the seat cushion is located below the ischial tuberosity. When the distance between the outer surface of the seat cushion cover and the anti-diving tube is 73.9 mm, and the angle between the anti-diving slope and the horizontal plane is 44°, by comparing the body pressure distribution data of the two seats, it can be seen that when the human body is in a normal sitting position, the peak pressure at the ischial tuberosity decreases from 9.7 kPa to 8.6 kPa, and the average pressure increases from 2.345 kPa to 2.393 kPa. Although the overall pressure on the sitting point is slightly increased, the pressure at the ischial tuberosity is significantly reduced. The greater the pressure, the greater the multiplication. That is to say, the distance between the outer surface of the seat cushion cover and the anti-diving tube is 73.9mm, and the angle between the anti-diving slope and the horizontal plane is 44°. The seat simulation method is used to compare the seat before and after adjustment. It is known from the simulation results that when the human body is in a normal sitting position, the peak value of the body pressure distribution of the adjusted and optimized seat is reduced, and the body pressure distribution gradient is flatter, indicating that the overall body pressure distribution of the seat is more uniform and reasonable, proving that the comfort of the anti-diving structure design of the adjusted and optimized seat has been significantly and effectively improved.

[0080] In another possible implementation, to ensure the scientific nature and persuasiveness of the simulation data obtained by this simulation method, the simulation method was also used to simulate a human body in a reclining sitting position. When the human finite element model was in a reclining sitting position, with the hip point as the reference point, the vertical angle between the head and the hip point was 39.4°, the horizontal straight-line distance between the foot and the hip point was 63.3 mm, the vertical straight-line distance between the foot and the hip point was 32.4 mm, the horizontal angle between the thigh and the hip point was 17.9°, and the horizontal angle between the calf and the hip point was 110.8°.

[0081] When the human body is in a lying position, the human body's buttocks and ischial tuberosity exert a greater gravity on the horizontal contact surface of the seat, so the comparison is the peak pressure value and average pressure value at the ischial tuberosity in the initial state and the adjusted state of the seat. Figure 8 and Figure 9As shown in the figure, the peak pressure of the seat cushion is located below the ischial tuberosity. When the distance between the outer surface of the seat cushion cover and the anti-dive tube is 73.9 mm, and the angle between the anti-dive slope and the horizontal plane is 44°, by comparing the body pressure distribution data of the two seats, it can be seen that when the human body is in a lying sitting position, the peak pressure at the ischial tuberosity is reduced from 24 kPa to 16 kPa. In other words, the distance between the outer surface of the seat cushion cover and the anti-dive tube is 73.9 mm, and the angle between the anti-dive slope and the horizontal plane is 44°. The seat simulation method was used to compare the seat before and after adjustment. The simulation results show that when the human body is in a lying sitting position, the peak pressure at the ischial tuberosity is greatly reduced, and the gradient of the body pressure distribution change in the high-pressure area is slightly slower than the anti-dive structure of the seat before adjustment. The pressure gradient value in the contact area can reflect whether the pressure distribution transition is slow or not. A larger transition will cause muscle stimulation and bring discomfort, which fully verifies that the anti-dive structure of the seat after adjustment has significantly and effectively improved the comfort in a specific posture.

[0082] Using the above-mentioned body pressure distribution-based seat simulation method, a human body finite element model, a first seat finite element model, and a second seat finite element model are established; the human body finite element model is assembled with the first seat finite element model to obtain a first seat simulation model; the human body finite element model is assembled with the second seat finite element model to obtain a second seat simulation model; a load test is performed on the first seat simulation model to obtain a first set of body pressure distribution data; a load test is performed on the second seat simulation model to obtain a second set of body pressure distribution data; and the seat comfort is verified based on the first and second sets of body pressure distribution data. Using the above-mentioned body pressure distribution-based seat simulation method, by establishing the human body finite element model and the seat finite element model, a finite element analysis is performed on the process of a person sitting on the seat using the finite element analysis method to obtain body pressure distribution data, and then the seat comfort is verified based on the body pressure distribution data obtained by the finite element analysis method. Because seat verification is achieved through the finite element analysis method, there is no need to produce multiple prototype seats and metal human body models, nor is there a need to mount a metal human body model on the seat to simulate the process of a real person sitting on the seat, thereby reducing the waste of time and R&D resources.

[0083] The present disclosure provides a seat simulation device based on body pressure distribution, such as Figure 10As shown, the seat simulation device 100 based on body pressure distribution includes: a finite element model establishment module 101, which establishes a human body finite element model, a first seat finite element model and a second seat finite element model; a simulation model assembly module 102, which is used to assemble the human body finite element model with the first seat finite element model to obtain a first seat simulation model; and assemble the human body finite element model with the second seat finite element model to obtain a second seat simulation model; a load test module 103, which is used to perform a load test on the first seat simulation model to obtain a first set of body pressure distribution data; and perform a load test on the second seat simulation model to obtain a second set of body pressure distribution data; and a comfort verification module 104, which is used to verify the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data.

[0084] The present disclosure provides a seat simulation device based on body pressure distribution, which is used to perform the following process: establishing a human body finite element model, a first seat finite element model, and a second seat finite element model; assembling the human body finite element model with the first seat finite element model to obtain a first seat simulation model; assembling the human body finite element model with the second seat finite element model to obtain a second seat simulation model; performing a load test on the first seat simulation model to obtain a first set of body pressure distribution data; performing a load test on the second seat simulation model to obtain a second set of body pressure distribution data; and verifying the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data. Through the above-mentioned seat simulation method based on body pressure distribution, by establishing the human body finite element model and the seat finite element model, a finite element analysis is performed on the process of a person sitting on the seat using a finite element analysis method to obtain body pressure distribution data, and then the seat comfort is verified based on the body pressure distribution data obtained by the finite element analysis method. Because the seat verification is achieved through the finite element analysis method, there is no need to produce multiple prototype seats and metal human body models, nor is there any need to install a metal human body model on the seat to simulate the process of a real person sitting on the seat, thereby reducing the waste of time and R&D resources.

[0085] In one possible implementation, the finite element model building module 101 is specifically used to obtain the ankle position and hip position of the human body when the human body finite element model is in a sitting position; adjust the ankle position according to the set step length to adjust the relative distance between the ankle position and the hip position, and obtain the human body finite element model in different postures.

[0086] In one possible implementation, the finite element model building module 101 is specifically used to obtain human body size data and human body three-dimensional data, wherein the human body three-dimensional data includes human body point cloud data and / or human body slice data; construct a skeletal geometric model based on the human body size data; and match the skeletal geometric model to the human body three-dimensional data to obtain a human body finite element model.

[0087] In one possible implementation, the first seat finite element model includes a first surface shell model and a first frame body model, wherein the first frame body model includes a first anti-diving tube model; the second seat finite element model includes a second surface shell model and a second frame body model, wherein the second frame body model includes a second anti-diving tube model, and the distance between the first surface shell model and the first anti-diving tube model is smaller than the distance between the second surface shell model and the second anti-diving tube model, wherein the first surface shell model and the second surface shell model are in the same plane.

[0088] In one possible implementation, the first skeleton model includes a first seat cushion suspension model, the second skeleton model includes a second seat cushion suspension model, a first anti-diving slope is formed between the first seat cushion suspension model and the first anti-diving tube model, and a second anti-diving slope is formed between the second seat cushion suspension model and the second anti-diving tube model, and the angle between the first anti-diving slope and the first plane is greater than the angle between the second anti-diving slope and the first plane.

[0089] In one possible implementation, the first seat finite element model also includes: a first sponge body model built by the first sponge parameters, and a first suspension body model built by the first suspension parameters; the second seat finite element model also includes: a second sponge body model built by the second sponge parameters, and a second suspension body model built by the second suspension parameters, wherein the first sponge parameters are the same as the second sponge parameters, and the first suspension parameters are the same as the second suspension parameters.

[0090] In one possible implementation, the simulation model assembly module 102 is specifically used to set a first constraint condition on the first seat finite element model; set a second constraint condition between the contact surface of the human body finite element model and the first seat finite element model, and assemble the human body finite element model and the second seat finite element model to obtain a second seat simulation model, including: setting a first constraint condition on the second seat finite element model; setting a second constraint condition between the contact surface of the human body finite element model and the second seat finite element model; wherein the first constraint condition is used to constrain the six directional degrees of freedom of the seat; the second constraint condition includes a tangential constraint condition and a normal constraint condition, the tangential constraint condition is set using a penalty function, and the normal constraint condition is set using a penalty function constraint enhancement setting.

[0091] In one possible implementation, the first body pressure distribution data includes a peak pressure value at the first ischial tuberosity, an average pressure value at the first ischial tuberosity, a peak pressure value at the first backrest, and an average pressure value at the first backrest; the second body pressure distribution data includes a peak pressure value at the second ischial tuberosity, an average pressure value at the second ischial tuberosity, a peak pressure value at the second backrest, and an average pressure value at the second backrest;

[0092] The comfort verification module 104 is used to determine that the seat comfort corresponding to the second seat finite element model is better than the seat comfort corresponding to the first seat finite element model when the first group of body pressure distribution data and the first group of body pressure distribution data meet preset conditions; wherein the preset conditions include: the peak pressure at the second ischial tuberosity is smaller than the peak pressure at the first ischial tuberosity; the amplitude of the change from the average pressure at the first ischial tuberosity to the average pressure at the second ischial tuberosity is smaller than a first preset value; the amplitude of the change from the peak pressure at the first backrest to the peak pressure at the second backrest is smaller than a second preset value; the amplitude of the change from the average pressure at the first backrest to the average pressure at the second backrest is smaller than a third preset value.

[0093] The seat simulation device based on body pressure distribution provided in the embodiment of the present invention can execute the seat simulation method based on body pressure distribution provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0094] Some other embodiments of the present disclosure further provide a seat, Figure 4 、 Figure 11-13 As shown, the seat is manufactured according to the structural parameters obtained by simulation using the seat simulation method based on body pressure distribution in the above embodiment.

[0095] In some embodiments, the seat 10 includes a seat frame, which includes an anti-diving tube 11, a rear cross bar 12 for the seat cushion, a seat pot bracket 13, and two seat side panels 14. The two seat side panels 14 are arranged to extend relative to each other, and the anti-diving tube 11 and the rear cross bar 12 for the seat cushion are arranged relative to each other and are respectively connected between the two seat side panels 14. The anti-diving tube 11 is located at one end of the seat side panel 14 away from the backrest, and the rear cross bar 12 for the seat cushion is located at the other end of the seat side panel 14, that is, the end of the rear cross bar 12 for the seat cushion close to the backrest. Welding holes are formed at both ends of the seat side panel 14. The anti-diving tube 11 is arranged higher than the rear cross bar 12 for the seat cushion. The seat pot bracket 13 is located between the two seat side panels 14 and overlaps with the anti-diving tube 11. The seat pot bracket 13 is arranged to extend upward as a whole to provide front end support for the seat cushion cover 15.

[0096] The seat also includes a cushion cover 15, which is mounted on the outside of the seat frame. The cushion cover 15 can be made of elastic materials such as fabric, artificial leather, and natural leather. The filler inside the seat can be selected from various foam materials, gas, or liquid fillers. Figure 13 h in the figure is the distance between the outer surface of the cushion cover 15 and the anti-diving tube 11; wherein h≥70 mm. In actual application, h can be 70 mm or 73.9 mm.

[0097] The seat frame also includes a cushion suspension 16, which is extended along the extension direction of the seat side panels 14. During the assembly process, the anti-diving tube 11 and the rear cross bar 12 of the cushion are first inserted into the welding holes at both ends of the two seat side panels 14 and welded to them. Then, the seat pot bracket 13 is overlapped and welded to the anti-diving tube 11. One end of the cushion suspension 16 is overlapped and fixed to the seat pot bracket 13, and the other end is overlapped and fixed to the rear cross bar 12 of the cushion. The two ends of the cushion suspension 16 can be fixedly connected by welding.

[0098] The middle portion of the seat suspension 16 along the extension direction is sunken relative to the two ends, and the portion of the seat suspension 16 close to the anti-diving tube 11 forms an anti-diving slope 17. Figure 13 The angle a in the figure represents the angle between the anti-dive slope 17 and the horizontal plane; where a≤40°, a can be 44°. By setting the distance between the outer surface of the seat cushion cover 15 and the anti-dive tube 11 to 73.9 mm and the angle between the anti-dive slope 17 and the horizontal plane to 44°, the seat's anti-dive structure is maintained while achieving more uniform and reasonable body pressure distribution, improving seat comfort and resolving the issue of a foreign body sensation at the front end of the seat, which can increase passenger fatigue after prolonged riding.

[0099] Still other embodiments of the present disclosure provide a vehicle comprising a seat as described in the above-mentioned embodiment, wherein the seat is manufactured using optimized structural parameters obtained by simulation using a seat simulation method based on body pressure distribution. The technical features of the seat used in the vehicle can be found in the seats described in the above-mentioned embodiments and will not be described in detail here. It should be noted that the seat provided by the present disclosure can be used not only in vehicles but also in ships or other mechanical devices, thereby improving the comfort of the seat and ensuring its safety.

[0100] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprises" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article or device. In the absence of further limitations, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0101] The above are merely specific embodiments of the present disclosure, intended to enable those skilled in the art to understand and implement the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is not limited to these embodiments, but is to be construed in the broadest manner consistent with the principles and novel features disclosed herein.

Claims

1. A seat simulation method based on body pressure distribution, characterized in that: include: Establish a human body finite element model, a first seat finite element model, and a second seat finite element model; Assembling the human body finite element model and the first seat finite element model to obtain a first seat simulation model; Assembling the human body finite element model and the second seat finite element model to obtain a second seat simulation model; performing a load test on the first seat simulation model to obtain a first set of body pressure distribution data; performing a load test on the second seat simulation model to obtain a second set of body pressure distribution data; The comfort of the seat is verified based on the first set of body pressure distribution data and the second set of body pressure distribution data.

2. The seat simulation method based on body pressure distribution according to claim 1, characterized in that: The method of establishing a human body finite element model comprises: When the human body finite element model is in a sitting position, obtaining the ankle position and hip point position of the human body; The ankle position is adjusted according to the set step length to adjust the relative distance between the ankle position and the hip point position, thereby obtaining finite element models of the human body in different postures.

3. The seat simulation method based on body pressure distribution according to claim 1 or 2, characterized in that: The method of establishing a human body finite element model comprises: Acquiring human body size data and human body three-dimensional data, wherein the human body three-dimensional data includes human body point cloud data and / or human body slice data; constructing a skeletal geometric model based on the human body size data; The skeleton geometric model is matched to the three-dimensional data of the human body to obtain a finite element model of the human body.

4. The seat simulation method based on body pressure distribution according to claim 1, characterized in that: The first seat finite element model includes a first surface shell model and a first skeleton model, wherein the first skeleton model includes a first anti-submersible tube model; The second seat finite element model includes a second surface shell model and a second frame model, wherein the second frame model includes a second anti-submersible pipe model. The distance between the first surface shell model and the first anti-submersible pipe model is smaller than the distance between the second surface shell model and the second anti-submersible pipe model, wherein the first surface shell model and the second surface shell model are in the same plane.

5. The seat simulation method based on body pressure distribution according to claim 4, characterized in that: The first skeleton model includes a first seat cushion suspension model, the second skeleton model includes a second seat cushion suspension model, a first anti-diving slope is formed between the first seat cushion suspension model and the first anti-diving tube model, and a second anti-diving slope is formed between the second seat cushion suspension model and the second anti-diving tube model. An included angle between the first anti-dive slope and the first plane is greater than an included angle between the second anti-dive slope and the first plane.

6. The seat simulation method based on body pressure distribution according to claim 5, characterized in that: The first seat finite element model also includes: a first sponge body model built by first sponge parameters, and a first suspension body model built by first suspension parameters; the second seat finite element model also includes: a second sponge body model built by second sponge parameters, and a second suspension body model built by second suspension parameters, wherein the first sponge parameters are the same as the second sponge parameters, and the first suspension parameters are the same as the second suspension parameters.

7. The seat simulation method based on body pressure distribution according to claim 4, characterized in that: Assembling the human body finite element model with the first seat finite element model to obtain a first seat simulation model includes: Setting a first constraint condition on the first seat finite element model; Setting a second constraint condition between the contact surface of the human body finite element model and the first seat finite element model, Assembling the human body finite element model with the second seat finite element model to obtain a second seat simulation model includes: Setting a first constraint condition on the second seat finite element model; Setting a second constraint condition between the contact surface of the human body finite element model and the second seat finite element model; Among them, the first constraint condition is used to constrain the six directional degrees of freedom of the seat; the second constraint condition includes a tangential constraint condition and a normal constraint condition, the tangential constraint condition is set using a penalty function, and the normal constraint condition is set using a penalty function constraint enhancement setting.

8. The seat simulation method based on body pressure distribution according to claim 1, characterized in that: The first body pressure distribution data includes a peak pressure at the first ischial tuberosity, an average pressure at the first ischial tuberosity, a peak pressure at the first backrest, and an average pressure at the first backrest; the second body pressure distribution data includes a peak pressure at the second ischial tuberosity, an average pressure at the second ischial tuberosity, a peak pressure at the second backrest, and an average pressure at the second backrest; Verifying the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data includes: If the first set of body pressure distribution data and the second set of body pressure distribution data meet a preset condition, determining that the seat comfort corresponding to the second seat finite element model is better than the seat comfort corresponding to the first seat finite element model; The preconditions include: The peak pressure at the second ischial tuberosity is smaller than the peak pressure at the first ischial tuberosity; A change from the average pressure value at the first ischial tuberosity to the average pressure value at the second ischial tuberosity is less than a first preset value; The variation range from the peak pressure at the first backrest to the peak pressure at the second backrest is less than a second preset value; The variation range from the average pressure value at the first backrest to the average pressure value at the second backrest is smaller than a third preset value.

9. A seat simulation device based on body pressure distribution, characterized in that: include: Finite element model building module, which builds the finite element model of the human body, the finite element model of the first seat, and the finite element model of the second seat; a first simulation model assembly module, configured to assemble the human body finite element model and the first seat finite element model to obtain a first seat simulation model; a second simulation model assembling module, configured to assemble the human body finite element model and the second seat finite element model to obtain a second seat simulation model; a first load test module, configured to perform a load test on the first seat simulation model to obtain a first set of body pressure distribution data; a second load test module, configured to perform a load test on the second seat simulation model to obtain a second set of body pressure distribution data; A comfort verification module is used to verify the comfort of the seat based on the first set of body pressure distribution data and the first set of body pressure distribution data.

10. A seat, characterized in that: The seat is manufactured by processing seat parameters obtained by simulation according to the seat simulation method based on body pressure distribution as described in any one of claims 1 to 8.

11. A vehicle, characterized in that: Comprising the seat as claimed in claim 10.

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