A rapid assessment method for vibration-induced injuries to typical organs of the human body in a reclining position

Abstract

The present invention relates to the technical field of assessing the degree of response of human organs under vibration impact, and specifically discloses a method for rapidly assessing injuries caused by vibration impact to typical organs of a reclining human body, comprising the following steps: first, obtaining dynamic response data of typical organs of a reclining real person under vibration impact; then, establishing a reclining human body-structure integrated multi-rigid body theoretical model and optimizing model parameters; determining the force damage threshold of the reclining human body under vibration impact; then, verifying the reclining human body-structure integrated multi-rigid body theoretical model in combination with impact experimental data of a reclining real person; calculating the acceleration response data of various parts of the reclining human body, comparing it with the force damage thresholds of different human organs given above, and then rapidly assessing the degree of response of the reclining human body. The present invention adopts the above-mentioned method for rapidly assessing injuries caused by vibration impact to typical organs of a reclining human body, providing core technical support for rapid assessment of injuries to reclining human bodies and anti-impact protection design.

Description

Technical Field

[0001] The present invention relates to the technical field of evaluating the response degree of human organs under vibration impact, and in particular to a method for quickly evaluating injuries caused by vibration impact to typical organs of a lying human body. Background Art

[0002] Underwater weapon explosions are a major means of damaging ship structures, equipment, and personnel. Underwater explosions can subject personnel inside the ship to vibration and shock. The impact response of the human body in both standing and sitting positions is currently a hot topic of research. However, the response of the human body in the recumbent position is equally important when a ship is suddenly struck by an underwater explosion at night.

[0003] In the field of human impact response research, cadaveric tests and numerical models are primarily used. Due to bioethical limitations and experimental measurement techniques, cadaveric tests are difficult to conduct effectively. Numerical models primarily include lumped mass parameter models, multi-body models, and finite element models. Lumped mass parameter models are widely used in the automotive industry for seated occupant vibration response analysis due to their simple parameter modeling process and rapid, relatively accurate solution. Finite element models offer higher computational accuracy than lumped mass parameter models, but require more computational resources and a more complex modeling process. Compared to other models, multi-body models are characterized by their ability to represent the longitudinal, vertical, and rotational motion of human organs. They are also more advantageous in expressing the three-dimensional behavior of the human body, simulating different postures, and describing the contact and interaction between structures and the human body, all while requiring fewer computational resources.

[0004] Existing research on multi-body human parameter models primarily focuses on specific body parts, lacking research on coupled human-structure loading models. Therefore, establishing an integrated multi-body theoretical model of underwater explosion-structure-lying human body is crucial for rapidly calculating the response of typical human organs to vibration shock. Summary of the Invention

[0005] The purpose of this invention is to provide a rapid assessment method for vibration impact injuries of typical human organs in a reclining position, providing core technical support for rapid assessment of personnel injuries in complex impact environments, on-site battlefield treatment, and subsequent personnel impact protection design. It has important basic research value and engineering guidance significance.

[0006] To achieve the above object, the present invention provides a method for rapidly assessing vibration-impact injuries to typical organs of a reclining human body, comprising the following steps:

[0007] S1. Obtain dynamic response data of typical human organs under vibration impact, which is used for subsequent optimization and verification of the multi-rigid body theoretical model of human-structure integration;

[0008] S2. Establish a multi-rigid body theoretical model of the reclining human body-structure integration, and treat the reclining human body as a mechanical system with multiple degrees of freedom, including mass, springs, and dampers.

[0009] S3, optimize the parameters of the multi-rigid body theoretical model;

[0010] S4. determining the stress injury threshold of a lying human body under vibration impact;

[0011] S5. Verify the lying human-structure integrated multi-rigid body theoretical model based on the lying human impact test data;

[0012] S6. Calculate the acceleration response data of various parts of the reclining human body using the recumbent human-structure integrated multi-rigid body theoretical model, and then compare it with the force damage thresholds of different human organs given in step S4 above, thereby quickly evaluating the response degree of the reclining human body.

[0013] Preferably, in step S1, a vertical vibration impact test of a real person lying down is conducted to obtain dynamic response data of typical organs of the human body lying down under vibration impact. The specific process is as follows:

[0014] S11. Calculate the regression equation of the mass of each body segment and the moment of inertia of each body segment according to the standard to determine the inertia parameters;

[0015] S12. Determine the center of mass of each body segment, and install acceleration sensors on the human body to arrange acceleration measurement points;

[0016] S13. Lie flat on the vertical impact machine to obtain acceleration data of various parts.

[0017] Preferably, in step S2, an integrated multi-rigid body theoretical model of a reclining human body coupled with a deck with 16 degrees of freedom is constructed, wherein the reclining human body multi-rigid body theoretical model is described by a linear multi-rigid body theoretical model with 15 degrees of freedom, and the modeling components are head, chest, pelvis, thigh, and calf from left to right. Each body segment has three movement directions, namely a horizontal movement x-axis and a vertical movement z-axis in the plane, and another rotational movement around the y-axis perpendicular to the plane. Then, the center of gravity position G of each part of the integrated multi-rigid body theoretical model is i Expressed as:

[0018]

[0019] where x i is the coordinate of the center of gravity in the x-axis direction, z i is the coordinate of the center of gravity in the z-axis direction;

[0020] Connection joint J between two main body sections ik The position is expressed as:

[0021]

[0022] in is the coordinate of the connection joint in the x-axis direction, is the coordinate of the connection joint in the z-axis direction;

[0023] The relationship between the position of the joints and the center of mass of each body segment is expressed as:

[0024]

[0025] in From the center of gravity G i To the connecting joint J between the two body segments k The rotation matrix R is given as:

[0026]

[0027] The contact point of each body segment with the rigid support is represented as:

[0028]

[0029] in is the coordinate of the contact point in the x-axis direction, is the coordinate of the contact point in the z-axis direction. The relationship between the position of the contact point and the center of gravity of each body segment is expressed as:

[0030]

[0031] in From the center of gravity G i To the contact point C between the body and the rigid support i vector of

[0032] The multi-rigid body theoretical model of the lying human body has fifteen coupled non-homogeneous differential equations, which can be expressed in matrix form as follows:

[0033]

[0034] Where M, K and C are the 15*15 mass matrix, spring stiffness matrix and damping coefficient matrix respectively; and z are 15*1 acceleration, velocity and displacement vectors respectively, f k and f c is the 15*1 coefficient vector used to support motion; and z0 are the velocity and displacement due to external excitation of the support;

[0035] Considering only the vertical motion of the deck, the lumped mass parameter model of the lying human body is coupled with the deck to obtain a lying human body-structure integrated multi-rigid body theoretical model. This lying human body-structure integrated multi-rigid body theoretical model consists of fifteen coupled homogeneous differential equations and one non-homogeneous differential equation. In combination with Taylor fluid-structure coupling, the underwater explosion pressure load is applied to the structural part of the coupled model:

[0036]

[0037]

[0038] Among them, A·P tot To take into account the cavitation effect of underwater explosion, the total pressure load acting on the deck structure is calculated, and A is the wet surface area.

[0039] Preferably, in step S3, the characteristic parameters of each organ of the recumbent human body model with 15 degrees of freedom are optimized, the initial values ​​of each parameter are set, and the upper and lower limits of each parameter are given to ensure that the parameters are not distorted while achieving the effect of improving the calculation speed; each iteration is output, and the maximum number of iterations and the number of pauses are set to infinite; a customized output function is used, the vertical acceleration response of each part of the recumbent human body parameter model is used as the evaluation standard, and the measured acceleration of the recumbent real-person impact test is used as the input reference for parameter optimization; when the acceleration of each part of the model is close to the acceleration measured in the experiment, the optimization is manually stopped to obtain the parameter optimization result.

[0040] Preferably, in step S4, the damage tolerance thresholds of the head, chest, pelvis, thigh and calf of a lying human body under vibration impact are determined;

[0041] Head Injury Assessment:

[0042] The head injury index HIC is the acceleration tolerance damage threshold of the head:

[0043]

[0044] Where: R(t) is t0≤t≤t e During this period, the resultant linear acceleration at the center of mass of the head;

[0045] t0 is the collision start time;

[0046] t e is the collision end time;

[0047] t1 and t2 must satisfy t0≤t1≤t2≤t e , the start and end time of the time period when HIC reaches its maximum value;

[0048] Chest injury assessment: Evaluate the acceleration limit of the entire body by measuring the probability of chest injury caused by vertebral acceleration;

[0049] Pelvic injury assessment: axial compression load-bearing capacity is assessed by pelvic tilt angle.

[0050] Preferably, step S5 specifically includes the following steps:

[0051] S51. Accuracy verification of multi-DOF lying human body model:

[0052] The upper and lower bounds of the multi-degree-of-freedom recumbent human body model system parameters were selected within a reasonable range. The measured accelerations from real-person recumbent tests were used as a benchmark for optimization calculations. The matrix parameters K, M, and C of the recumbent human body model were optimized so that the calculated peak values ​​of the acceleration responses of each part and the peak values ​​of the measured data were within a pre-set error range.

[0053] S52, Taylor fluid-structure coupling load application accuracy verification:

[0054] A finite element model of the floating platform was created and solved using the Abaqus underwater explosion sound-solid coupling module. A load with bubble pulsation pressure was input, and the dynamic response of the deck structure was solved based on the Taylor principle. By comparing the deck acceleration response data calculated using the Taylor principle with the numerical simulation results, the consistency between the responses of the two in the shock wave stage and the bubble pulsation stage was analyzed, thereby verifying the accuracy of the underwater explosion pressure load application.

[0055] Therefore, the present invention adopts the above-mentioned rapid assessment method for vibration impact injuries of typical organs of the lying human body, and the beneficial effects are as follows:

[0056] This paper, based on relevant standards, conducts real-person impact tests in a reclining position, obtains real-world response data, and constructs an integrated multi-rigid-body theoretical model of underwater explosion-structure-reclining human bodies. This model is then optimized using the response data. Finally, combining relevant damage thresholds, it rapidly assesses the injuries of reclining crew members in complex impact environments. This provides core technical support for on-site naval combat rescue and subsequent personnel impact protection design, possessing significant fundamental research value and engineering guidance.

[0057] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is an overall flow chart of an embodiment of a method for rapidly assessing vibration-impact injuries to typical organs of a lying human body according to the present invention;

[0059] Figure 2This is a schematic diagram of measurement point arrangement for a lying-down real-person experiment according to an embodiment of a method for rapid assessment of vibration-impact injuries to typical organs of a lying-down human body according to the present invention;

[0060] Figure 3 Schematic diagram of a real-person impact experiment in a reclining position, showing an embodiment of a method for rapidly assessing vibration-impact injuries to typical organs of a reclining human body according to the present invention;

[0061] Figure 4 It is a reclining human-structure integrated multi-rigid body theoretical model according to an embodiment of a method for rapidly assessing vibration-impact injuries of typical organs of a reclining human body of the present invention;

[0062] Figure 5 This is a graph showing the relationship between spinal acceleration response and chest injury probability in an embodiment of a method for rapidly assessing vibration-induced injuries to typical organs of a reclining human body according to the present invention;

[0063] Figure 6 The figure is a schematic diagram of a finite element simulation of an underwater explosion of a floating platform according to an embodiment of a method for rapidly assessing vibration-impact injuries to typical organs of a lying human body according to the present invention. DETAILED DESCRIPTION

[0064] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0065] Unless otherwise defined, technical or scientific terms used in the present invention shall have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

[0066] like Figure 1 As shown, a rapid assessment method for vibration impact injuries of typical organs of the lying human body comprises the following steps:

[0067] S1. First, conduct a vertical vibration impact test on a real person in a reclining position to obtain dynamic response data of typical organs of the reclining human body under vibration impact, which will be used for the subsequent optimization and verification of the reclining human-structure integrated multi-rigid body theoretical model;

[0068] Through the vertical vibration impact test of a real person lying down, the dynamic response data of typical organs of the human body under vibration impact are obtained. The specific process is as follows:

[0069] S11. Calculate the regression equation of the mass of each body segment and the moment of inertia of each body segment according to the standard to determine the inertia parameters;

[0070] Experimental setup:

[0071] For the trial, considering the representativeness of the selected volunteers and the time constraints of the trial, no fewer than eight male volunteers were selected based on the 50th percentile of the Chinese population. The selected volunteers were aged between 23 and 30 years old and in good health, with no muscle or bone disorders. Statistics showed that the volunteers were 170 ± 3 cm tall, weighed 65 ± 3 kg, and had a body mass index (BMI) of M / H2 ≤ 24, which generally meets the Chinese adult body size standards (GB10000-1988).

[0072] Considering the human body as a multi-body system, it's necessary to understand the inertial parameters of each body segment, such as mass and moment of inertia. Based on extensive real-life test data, the national standard GB / T17245-2004, "Inertial Parameters of the Adult Human Body," specifies a method for segmenting the adult human body and provides inertial parameters such as mass distribution and moment of inertia for each segment. This standard is widely used in vehicle safety protection, human motion analysis, and motion simulation, and guides the development of body mannequins and prosthetic limbs for the disabled. The inertial parameters of the volunteers were determined using the regression equations provided in the standard for calculating the mass and moment of inertia of each segment.

[0073] S12. Determine the center of mass of each body segment, and install acceleration sensors on the human body to arrange acceleration measurement points;

[0074] When installing an accelerometer on the human body, in order to obtain accurate data, the accelerometer must be placed as close as possible to the center of mass of each segment of the human body. Therefore, the center of mass of each segment must be determined. Figure 2 The human body segmentation is shown, and the center of mass position of each segment is determined according to the regression equation given by the above standards.

[0075] S13, lying position The real person lies flat on his back. Figure 3 Acceleration data for various parts were obtained on the vertical impact machine shown in Figure 1. The impact response measurement points were primarily acceleration (W1-W7). The specific distribution statistics are shown in Table 1.

[0076] Table 1 Statistics of measurement points of lying real people

[0077]

[0078] The acceleration sensor at the structural measurement point is installed using a gluing + bolting method. First, fix the threaded PE mounting block (cube, side length 20mm) to the bed support frame with glue, and then fix the acceleration sensor to the mounting block with a screw. The acceleration sensor at the human body measurement point is installed using an adjustable flexible strap + bolting method. First, fix the PE mounting block to the flexible strap by sewing, as shown in the figure. Figure 2 As shown, the acceleration sensor is fixed on the mounting block by a screw. Finally, the flexible strap is adjusted and firmly tied to the various parts of the human body listed in Table 1.

[0079] To ensure the representativeness and reliability of the test data, the acceleration peaks of the measured lying people were processed for different body parts, the maximum and minimum values ​​were removed, and the remaining data were averaged. The obtained average value was used as the benchmark for subsequent parameter optimization.

[0080] S2. Establish a multi-rigid body theoretical model of the reclining human body-structure integration, and treat the reclining human body as a mechanical system with multiple degrees of freedom, including mass, springs, and dampers.

[0081] The establishment of the model is based on the human body structure with similar dynamic characteristics to the entity, and the ultimate goal is to determine the physical parameters in the model (such as the stiffness K, mass M, and damping C of each organ structure).

[0082] like Figure 4 As shown in the figure, a 16-degree-of-freedom integrated multi-rigid body theoretical model of a reclining human body coupled with a deck is constructed. The reclining human body multi-rigid body theoretical model is described using a 15-degree-of-freedom linear multi-rigid body theoretical model. The modeled components from left to right are the head, chest, pelvis, thigh, and calf. Each body segment has three motion directions: a horizontal motion x-axis and a vertical motion z-axis in the plane, and another rotational motion around the y-axis perpendicular to the plane. The center of gravity position G of each part of the integrated multi-rigid body theoretical model is: i Expressed as:

[0083]

[0084] where x i is the coordinate of the center of gravity in the x-axis direction, z i is the coordinate of the center of gravity in the z-axis direction.

[0085] Connection joint J between two main body sections ik The position is expressed as:

[0086]

[0087] in is the coordinate of the connection joint in the x-axis direction, is the coordinate of the connection joint in the z-axis direction.

[0088] The relationship between the position of the joints and the center of mass of each body segment is expressed as:

[0089]

[0090] in From the center of gravity G i To the connecting joint J between the two body segments k The rotation matrix R is given as:

[0091]

[0092] The contact point of each body segment with the rigid support is represented as:

[0093]

[0094] in is the coordinate of the contact point in the x-axis direction, is the coordinate of the contact point in the z-axis direction.

[0095] The relationship between the location of the contact point and the center of gravity of each body segment can be expressed as:

[0096]

[0097] in From the center of gravity G i To the contact point C between the body and the rigid support i vector of

[0098] The data measured in the above-mentioned lying-position real-person experiment and combined with relevant standards are used to determine the coordinates of the center of gravity of each component, the joints between adjacent components, and the contact points between the components and the vibration rigid support.

[0099] The 15-degree lying human multi-rigid body theoretical model of the present invention has 15 coupled non-homogeneous differential equations, which can be expressed in matrix form as follows:

[0100]

[0101] Where M, K and C are the 15*15 mass matrix, spring stiffness matrix and damping coefficient matrix respectively; and z are 15*1 acceleration, velocity and displacement vectors respectively, f k and f c is the 15*1 coefficient vector used to support motion; and z0 are the velocity and displacement due to the external excitation of the support; M, K, C, f k and f c The detailed information of is given in Table 2. This set of equations represents the dynamic characteristics of the system in terms of mass, stiffness and damping. Each matrix is ​​a symmetric square matrix with a size equal to the number of degrees of freedom of the system.

[0102] Table 2 Parameter statistics of human multi-rigid body theoretical model

[0103]

[0104]

[0105] The flow field pressure exerted on the structure by underwater explosion can be ideally loaded using the Taylor principle, and the correctness of load application and structural response can be verified using acoustic-structure coupling numerical simulation.

[0106] For simplicity and without loss of generality, only the vertical motion of the deck is considered. The lumped mass parameter model of the lying human body is coupled with the deck to obtain a lying human body-structure integrated multi-rigid body theoretical model. This lying human body-structure integrated multi-rigid body theoretical model consists of fifteen coupled homogeneous differential equations and one non-homogeneous differential equation. The Taylor fluid-structure coupling is combined to apply the underwater explosion pressure load to the structural part of the coupled model:

[0107]

[0108]

[0109] Among them, A·P tot To consider the cavitation effect of underwater explosion, the total pressure load acting on the deck structure is: A is the wet surface area, M is 16 , K 16 、C 16 Detailed information is shown in Table 3.

[0110] Table 3 Parameters of the lying human-structure integrated multi-rigid body theoretical model

[0111]

[0112]

[0113] S3, optimize the parameters of the multi-rigid body theoretical model;

[0114] The characteristic parameters of each organ in the 15-degree-of-freedom lying human body model are optimized, the vertical acceleration response of each part of the lying human body parameter model is used as the evaluation standard, and the measured acceleration of the lying real-life impact test is used as the benchmark for parameter optimization.

[0115] The initial values ​​of each parameter were set according to existing relevant literature, and upper and lower limits of each parameter were given to ensure that the parameters were not distorted while achieving the effect of improving the calculation speed. Each iteration was output, and the maximum number of iterations and the number of pauses were set to infinite. A custom output function was used, and the vertical acceleration response of each part of the recumbent human body parameter model was used as the evaluation standard. The measured acceleration of the recumbent real-person impact test was used as the input benchmark for parameter optimization. When the acceleration of each part of the model was close to the acceleration measured in the experiment, the optimization was manually stopped to obtain the parameter optimization results.

[0116] S4. determining the stress injury threshold of a lying human body under vibration impact;

[0117] Combined with existing literature, the damage tolerance thresholds of the head, chest, pelvis, thigh, and calf of the lying human body under vibration impact were determined and damage assessment was performed;

[0118] Head Injury Assessment:

[0119] The head injury index (HIC) is widely used. Regulations stipulate that HIC = 1000 is the acceleration tolerance injury threshold for the head, and the HIC calculation time interval (t1-t2) is stipulated to be 15ms:

[0120]

[0121] Where: R(t) is t0≤t≤t e During this period, the resultant linear acceleration at the center of mass of the head (g);

[0122] t0 is the collision start time (s);

[0123] t e is the collision termination time (s);

[0124] t1 and t2 must satisfy t0≤t1≤t2≤t e , the start and end time of the time period when HIC reaches its maximum value (s);

[0125] Chest Injury Assessment:

[0126] Currently, the acceleration standard is widely used in automobile safety. European and North American safety standards adopt this standard. The Federal National Motor Vehicle Safety Standard FMVSS208 stipulates that the standard for occupant collision protection should not exceed 60g and the duration should not exceed 3 milliseconds. Mertz et al. conducted a large number of sliding tests and restraint system tests and concluded that the injury standard for chest frontal collision acceleration is 60g; Cavanaugh et al. conducted side collision tests and concluded that the acceleration injury tolerance value is between 60 and 80g. Figure 5 Shown is the probability of injury to the chest caused by vertebral column acceleration, which is used to evaluate the acceleration limit of the whole body;

[0127] Pelvic injury assessment: The axial compression bearing capacity was assessed by the pelvic tilt angle, and when the pelvic tilt angle was 13.2°, the axial compression bearing capacity was the strongest, approximately 8.0 kN.

[0128] Thigh injury assessment: The thigh injury threshold is 10.36kN.

[0129] Calf injury assessment: The thigh injury threshold is 8.5kN.

[0130] S5. Verify the lying human-structure integrated multi-rigid body theoretical model based on the lying human impact test data, which specifically includes the following steps:

[0131] S51. Accuracy verification of multi-DOF lying human body model:

[0132] During the experiment, the parameters of the mass, stiffness, and damping coefficient of various human organs corresponding to the recumbent human-structure integrated multi-rigid-body model will vary due to the body shapes of the test persons. At the same time, the specific values ​​of the mass, stiffness, and damping coefficient of various human organs cannot be determined through conventional testing.

[0133] When optimizing the model parameters, the upper and lower bounds of the multi-degree-of-freedom recumbent human body model system parameters were first selected within a reasonable range. Based on the measured accelerations from the recumbent human body test, the matrix parameters K, M, and C of the recumbent human body model were optimized so that the calculated peak acceleration response of each part and the peak value of the measured data were within a pre-set error range.

[0134] S52, Taylor fluid-structure coupling load application accuracy verification:

[0135] Create Figure 6 The finite element model of the floating platform shown in the figure is solved using the Abaqus underwater explosion sound-solid coupling module. The charge m c The explosion distance is consistent with the values ​​in the Taylor principle in the above integrated model. Figure 6 Measurement point A is the response output point. Because the mass of a human body is much smaller than that of the floating platform, its effect on the floating platform mass is neglected in the numerical calculation. A load with pulsating bubble pressure is also input, and the dynamic response of the deck structure is solved based on the Taylor principle. The values ​​of the total deck mass M0 and the wetted surface area A are consistent with those used in the Taylor fluid-structure interaction principle.

[0136] By comparing the deck acceleration response data calculated using the Taylor principle with the numerical simulation results, the consistency between the responses of the two in the shock wave stage and the bubble pulsation stage is analyzed to verify the accuracy of the application of underwater explosion pressure load.

[0137] S6. Using the multi-rigid body theoretical model of the lying human body and structure integration, the acceleration response data of each part of the lying human body under different charges and explosion distances are quickly calculated. Then, the peak value of the acceleration response of each part is multiplied by the mass of the corresponding part to obtain the peak force of this part.

[0138] The damage degree of each organ is then evaluated by comparing it with the damage criteria of different human organs given in the above step S4, thereby realizing a rapid evaluation of the response degree of the lying human body under different impact environments.

[0139] Therefore, the present invention adopts the above-mentioned rapid assessment method of vibration impact injuries to typical human organs in a reclining position, which can quickly assess the injuries of reclining crew members under various complex impact environments, provide core technical support for on-site treatment in naval battles and subsequent personnel impact protection design, and has important basic research value and engineering guidance significance.

[0140] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A rapid assessment method for vibration-induced injuries to typical organs of a reclining human body, characterized in that: The following steps are involved: S1. Obtain dynamic response data of typical human organs under vibration impact, which is used for subsequent optimization and verification of the multi-rigid body theoretical model of human-structure integration; S2. Establish a multi-rigid body theoretical model of the reclining human body-structure integration, and treat the reclining human body as a mechanical system with multiple degrees of freedom, including mass, springs, and dampers. S3, optimize the parameters of the multi-rigid body theoretical model; S4. determining the stress injury threshold of a lying human body under vibration impact; S5. Verify the lying human-structure integrated multi-rigid body theoretical model based on the lying human impact test data; S6. Calculate the acceleration response data of various parts of the reclining human body using the recumbent human-structure integrated multi-rigid body theoretical model, and then compare it with the force damage thresholds of different human organs given in step S4 above, thereby quickly evaluating the response degree of the recumbent human body; In step S2, an integrated multi-rigid body theoretical model of a reclining human body coupled with a deck with 16 degrees of freedom is constructed, wherein the reclining human body multi-rigid body theoretical model is described by a linear multi-rigid body theoretical model with 15 degrees of freedom. The modeling parts are head, chest, pelvis, thigh, and calf from left to right. Each body segment has three movement directions, namely a horizontal movement x-axis and a vertical movement z-axis in the plane, and another rotational movement around the y-axis perpendicular to the plane. The center of gravity position of each part of the integrated multi-rigid body theoretical model is Expressed as: ； in is the coordinate of the center of gravity in the x-axis direction, is the coordinate of the center of gravity in the z-axis direction; Connecting joint between two main body sections The position is expressed as: ； in is the coordinate of the connection joint in the x-axis direction, is the coordinate of the connection joint in the z-axis direction; The relationship between the position of the joints and the center of mass of each body segment is expressed as: ； in From the center of gravity To the connecting joint between two body segments The vector and the rotation matrix is given as: ； The contact point of each body segment with the rigid support is represented as: ； in is the coordinate of the contact point in the x-axis direction, is the coordinate of the contact point in the z-axis direction. The relationship between the position of the contact point and the center of gravity of each body segment is expressed as: ； in From the center of gravity To the point of contact between the body and the rigid support vector of The multi-rigid body theoretical model of the lying human body has fifteen coupled non-homogeneous differential equations, which can be expressed in matrix form as follows: ； Where M, K and C are Mass matrix, spring stiffness matrix, and damping coefficient matrix; 、 and They are acceleration, velocity, and displacement vectors, and It is used to support movement coefficient vector; and are the velocities and displacements due to external excitation of the supports; Considering only the vertical motion of the deck, the lumped mass parameter model of the lying human body is coupled with the deck to obtain a lying human body-structure integrated multi-rigid body theoretical model. This lying human body-structure integrated multi-rigid body theoretical model consists of fifteen coupled homogeneous differential equations and one non-homogeneous differential equation. In combination with Taylor fluid-structure coupling, the underwater explosion pressure load is applied to the structural part of the coupled model: ； ； in In order to consider the cavitation effect of underwater explosion, the total pressure load acting on the deck structure is is the wet surface area.

2. The rapid assessment method for vibration-impact injuries of typical organs of a reclining human body according to claim 1, characterized in that: In step S1, a vertical vibration impact test is conducted on a real person lying down to obtain dynamic response data of typical organs of the human body under vibration impact. The specific process is as follows: S11. Calculate the regression equation of the mass of each body segment and the moment of inertia of each body segment according to the standard to determine the inertia parameters; S12. Determine the center of mass of each body segment, and install acceleration sensors on the human body to arrange acceleration measurement points; S13. Lie flat on the vertical impact machine to obtain acceleration data of various parts.

3. The rapid assessment method for vibration-impact injuries of typical organs of a reclining human body according to claim 2, characterized in that: In step S3, the characteristic parameters of each organ in the 15-degree-of-freedom recumbent human body model are optimized, initial values ​​for each parameter are set, and upper and lower limits for each parameter are given to ensure that the parameters are not distorted while achieving the effect of improving the calculation speed; each iteration is output, and the maximum number of iterations and the number of pauses are set to infinite; a custom output function is defined, and the vertical acceleration response of each part of the recumbent human body parameter model is used as the evaluation standard. The measured acceleration of the recumbent real-person impact test is used as the input reference for parameter optimization; when the acceleration of each part of the model is close to the acceleration measured in the experiment, the optimization is manually stopped to obtain the parameter optimization results.

4. The rapid assessment method for vibration-impact injuries of typical organs of a reclining human body according to claim 3, characterized in that: In step S4, the damage tolerance thresholds of the head, chest, pelvis, thigh, and calf of the lying human body under vibration impact are determined; Head Injury Assessment: Head injury indicators The acceleration tolerance damage threshold of the head is: ; Where: for During this period, the resultant linear acceleration at the center of mass of the head; is the collision start time; is the collision end time; Need to meet ,make The start and end times of the time period in which the maximum value is reached; Chest injury assessment: Evaluate the acceleration limit of the entire body by measuring the probability of chest injury caused by vertebral acceleration; Pelvic injury assessment: axial compression load-bearing capacity is assessed by pelvic tilt angle.

5. The rapid assessment method for vibration-impact injuries of typical organs of a reclining human body according to claim 4, characterized in that: Step S5 specifically includes the following steps: S51. Accuracy verification of multi-DOF lying human body model: The upper and lower bounds of the multi-degree-of-freedom recumbent human body model system parameters were selected within a reasonable range. The measured accelerations from real-person recumbent tests were used as a benchmark for optimization calculations. The matrix parameters K, M, and C of the recumbent human body model were optimized so that the calculated peak values ​​of the acceleration responses of each part and the peak values ​​of the measured data were within a pre-set error range. S52, Taylor fluid-structure coupling load application accuracy verification: A finite element model of the floating platform was created and solved using the Abaqus underwater explosion sound-solid coupling module. A load with bubble pulsation pressure was input, and the dynamic response of the deck structure was solved based on the Taylor principle. By comparing the deck acceleration response data calculated using the Taylor principle with the numerical simulation results, the consistency between the responses of the two in the shock wave stage and the bubble pulsation stage was analyzed, thereby verifying the accuracy of the underwater explosion pressure load application.

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