A neck muscle impact injury analysis method based on dummy experimental data driving
By using a data-driven approach based on dummy experiments, combined with the Hybrid III dummy size and the OpenSim platform, the fragmentation problem in muscle damage assessment in existing technologies has been solved, enabling multi-dimensional quantitative assessment under controllable conditions and supporting safety design optimization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- THE NAVAL MEDICAL UNIV OF PLA
- Filing Date
- 2026-03-31
- Publication Date
- 2026-06-26
AI Technical Summary
Existing technologies cannot quantify the risk of deep neck muscle injury under controlled conditions. The disconnect between experiments and simulations, the lack of model standardization, and the limited dimensions of injury assessment lead to inadequate evaluation.
Using a data-driven approach based on dummy experiments, a data transmission chain was established. The model was scaled using the 50th percentile male dummy size of Hybrid III, and musculoskeletal simulation was performed using the OpenSim platform to obtain cervical joint angles, loads, and muscle activation. Multi-dimensional indicators were used to assess the risk of injury.
It enables the quantification of deep muscle injury risk under controllable conditions, with strong model adaptability, reliable evaluation results, and direct mapping to the optimization of safety design parameters.
Smart Images
Figure CN122287111A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the fields of biomechanical engineering and safety protection technology, and more specifically, to a method for analyzing neck muscle impact injuries based on dummy experimental data. Background Technology
[0002] Neck muscle injuries are a major cause of whiplash injury (WAD) in car crashes and kinetic impacts. Current medical assessments rely on imaging examinations, which cannot capture the transient impact process; cadaver experiments are limited by ethical considerations and sample scarcity; live volunteer testing is limited to low-intensity impacts (≤4g) due to safety risks, and surface electromyography cannot monitor deep muscle responses. While multibody dynamics dummy models (such as HybridIII) can obtain kinematic data, they lack realistic muscle anatomy, and muscle force distribution relies on empirical assumptions, making it difficult to quantify muscle-level injury risk.
[0003] Musculoskeletal simulation technologies (such as OpenSim) have provided new avenues for injury analysis, but significant limitations remain: motion boundary conditions often employ idealized theoretical loads, which are disconnected from real impact data; model scaling relies on individual medical images and lacks a geometric adaptation process based on standardized dummy sizes; injury assessment often depends on single muscle strength indicators, neglecting key biomechanical mechanisms such as muscle activation timing and energy uptake rate (EAR). The disconnect between experiment and simulation, insufficient model generalization, and one-sided assessment dimensions prevent existing methods from quantifying the risk of deep muscle injury under controlled conditions. Summary of the Invention
[0004] To address the three major problems existing in the background technology—the disconnect between experiment and simulation, the lack of model standardization, and the single dimension of damage assessment—the purpose of this invention is to provide a neck muscle impact injury analysis method driven by dummy experimental data. This method establishes a data transfer chain between dummy impact experiments and musculoskeletal simulation; constructs a standardized dummy size adaptation model scaling process; and proposes a multi-dimensional muscle injury quantitative assessment system, providing new technical support for musculoskeletal simulation technology.
[0005] To achieve the above technical objectives, this application provides a method for analyzing neck muscle impact injuries based on dummy experimental data, comprising the following steps:
[0006] The neck motion trajectory parameters collected in the dummy impact test experiment will be used as the boundary conditions for the musculoskeletal model simulation.
[0007] Import a pre-defined neck musculoskeletal model into the OpenSim platform, and after geometrically scaling the model according to the standardized dummy size, obtain the cervical joint angle, cervical joint load, and the activation and muscle force distribution of each muscle.
[0008] Based on the extracted peak muscle strength, muscle activation sequence, and energy absorption rate per unit mass of muscle, the risk of impact muscle injury is assessed.
[0009] Preferably, during the acquisition of neck motion trajectory parameters, the neck motion trajectory parameters are obtained by acquiring the original time series of displacement, velocity, and acceleration of the dummy's head-neck reference point.
[0010] Preferably, during geometric scaling, the standardized dummy size is the neck geometry parameter of the 50th percentile male dummy of Hybrid III. The scaling process includes: adjusting the intervertebral spacing of the model based on the dummy's cervical spine length; and adjusting the muscle attachment point position based on the cross-sectional size of the dummy's neck.
[0011] Preferably, when obtaining the activation level and muscle strength distribution of each muscle, a static optimization algorithm is used to calculate the activation level and muscle strength distribution of each muscle, wherein the objective function of the static optimization algorithm is:
[0012] ;
[0013] The constraints are:
[0014]
[0015] in: The activation level of the i-th muscle; This is the joint torque vector output in step 3; For muscle lever arm matrix; This is the muscle force vector.
[0016] Preferably, when obtaining the energy absorption rate per unit mass of muscle, the energy absorption rate per unit mass of muscle is expressed as:
[0017] ;
[0018] In the formula, For the time window of impact; This is the muscle force vector; is a time function of muscle contraction velocity; m represents the mass of the target muscle.
[0019] Preferably, when assessing the risk of impact muscle injury, a muscle injury threshold model is used, wherein the muscle injury threshold model is expressed as:
[0020]
[0021] In the formula, F max F0 represents the maximum value of the muscle force time series, that is, the peak muscle force generated by a specific muscle within the time window of the impact. F0 represents the maximum isometric contractile force of the muscle.
[0022] Based on the same inventive concept, this invention discloses an application of a neck muscle impact injury analysis method driven by dummy experimental data: applying the injury risk assessment results to the design parameter optimization scheme of car seat safety systems or sports protective gear.
[0023] Based on the same inventive concept, this invention discloses a neck muscle impact injury analysis system driven by dummy experimental data, the system comprising:
[0024] The data processing module is used to take the neck motion trajectory parameters collected in the dummy impact test experiment as the boundary conditions for the musculoskeletal model simulation.
[0025] The feature extraction module is used to import a preset neck muscle and skeleton model into the OpenSim platform, and after geometrically scaling the model according to the standardized dummy size, obtain the cervical joint angle, cervical joint load, and the activation degree and muscle force distribution of each muscle.
[0026] The risk assessment module is used to assess the risk of impact muscle injury based on the extracted peak muscle strength, muscle activation sequence, and energy absorption rate per unit mass of muscle.
[0027] The present invention discloses the following technical effects:
[0028] This invention solves the problem of traditional simulation relying on idealized loads by collecting the head-neck reference point trajectory (displacement / velocity / acceleration) from dummy impact experiments;
[0029] This invention utilizes HybridIII 50th percentile dummy neck geometry parameters to perform model scaling (linear scaling of intervertebral distance + radial adjustment of muscle attachment points), achieving anatomical adaptation to industry-standard dummies. The model can be reconstructed, avoiding evaluation biases caused by individual differences;
[0030] This invention integrates three indicators: mechanics, time domain, and energy. Peak muscle strength reflects the instantaneous load limit, muscle activation sequence locates the high-risk time window for injury, and energy absorption rate per unit mass (EAR) quantifies the injury mechanism of eccentric contraction.
[0031] Enhance the efficiency of engineering application transformation: Damage risk level output is directly mapped to the optimization of safety design parameters. Attached Figure Description
[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0033] Figure 1 This is a schematic diagram of the method described in this invention;
[0034] Figure 2 This is the human head and neck muscle and skeletal model described in this invention;
[0035] Figure 3 These are the original model and the scaled model described in this invention;
[0036] Figure 4 These are the locations of the marker points on the head and neck musculoskeletal model described in this invention;
[0037] Figure 5 The input and output content of the Opensim software scaling tool described in this invention;
[0038] Figure 6 The input and output contents of the Opensim software inverse kinematics tool described in this invention;
[0039] Figure 7 The input and output contents of the Opensim software inverse dynamics tool described in this invention;
[0040] Figure 8 These are the input and output contents of the Opensim software static optimization tool described in this invention. Detailed Implementation
[0041] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0042] like Figures 1-8 As shown, this invention provides a neck muscle impact injury analysis method driven by dummy experimental data, applicable to quantifying the risk of deep neck muscle injury under impact loads in automotive collision safety and sports protective equipment development. Specifically, it includes the following:
[0043] Obtain impact test data from a dummy and use the head-neck reference point trajectory as the boundary condition for OpenSim simulation.
[0044] Import the preset neck muscle and skeleton model; perform geometric scaling based on the neck geometry parameters of the HybridIII 50th percentile male dummy: the intervertebral spacing is scaled linearly, and the muscle attachment point position is adjusted radially according to the cross-sectional dimensions.
[0045] Perform dynamic analysis:
[0046] Inverse kinematics: Based on the neck movement trajectory parameters, the cervical joint angle is calculated and calibrated through inverse kinematics to make the model trajectory match the input data (objective function: root mean square error of trajectory ≤ 5%).
[0047] Inverse dynamics: Based on joint angle input, the cervical joint load is solved using inverse dynamics;
[0048] Static optimization: Based on joint load input, the activation degree and muscle force distribution of each muscle are calculated using a static optimization algorithm; the muscle force distribution is calculated with the objective of minimizing the sum of squares of muscle activation degrees. The objective function of the static optimization algorithm is:
[0049] ;
[0050] The constraints are:
[0051]
[0052] in: The activation level of the i-th muscle; This is the joint torque vector; For muscle lever arm matrix; This is the muscle force vector.
[0053] Damage Quantification: Three damage indicators were extracted: Peak muscle strength: the maximum value of muscle force over time; Muscle activation sequence: the duration window of activation > 0.5; Energy absorption rate per unit mass of muscle (EAR).
[0054] ;
[0055] In the formula, For the time window of impact; This is the muscle force vector; Let m be the time function of muscle contraction velocity; m represents the mass of the target muscle.
[0056] Muscle contraction speed It can be obtained through the following formula:
[0057]
[0058] in: Muscle length time series output by Opensim;
[0059] Input damage threshold model to assess risk level:
[0060]
[0061] In the formula, F max F0 represents the maximum value of the muscle force time series, that is, the peak muscle force generated by a specific muscle within the time window of the impact. F0 represents the maximum isometric contractile force of the muscle.
[0062] Example: This invention discloses a method for analyzing neck muscle impact injuries based on dummy experimental data, such as... Figure 1 As shown, exemplarily applied to neck muscle injury analysis in a car collision scenario, the specific steps include:
[0063] Step 1: Data Acquisition. A frontal collision test was conducted using a Hybrid III 50th percentile male dummy. Please refer to [link to relevant documentation]. Figure 4 Marking points were placed at corresponding positions on the head and neck of the dummy, and high-speed cameras were used to capture the trajectory of the marking points during the collision process.
[0064] Step 2: Model Import and Scaling. Import the head and neck musculoskeletal model. For the input and output details of the scaling tool in the Opensim simulation platform, please refer to [link / reference needed]. Figure 5 In the diagram, "Scaling" represents the scaling tool in the software. Each tool in the Opensim simulation platform requires its own configuration file. To use the scaling tool, the "Scaling Tool Configuration File" needs to be imported into the scaling tool, and the "Scaling Tool Configuration File" in turn requires the "Model Virtual Marker Point Set" for positioning. The scaling tool has two inputs: the "Human Head and Neck Musculoskeletal Model" and the "Experimentally Measured Marker Point Trajectory File". The output after scaling is the "Scaled Model", and subsequent calculations are based on the "Scaled Model".
[0065] Step 3: Inverse kinematics analysis, please refer to [link / reference]. Figure 6 In the diagram, "Inverse Kinematics" represents the inverse kinematics solution tool. To use the inverse kinematics solution tool, you need to import the "Inverse Kinematics Settings File" into the solution tool first. The input to the inverse kinematics solution tool is the "scaled model" and the "trace file of the marker points measured in the experiment" obtained by the scaling tool in step 2. The output is the "trajectory motion file calculated by inverse kinematics", which is also the input file for the subsequent inverse dynamics and static optimization steps.
[0066] Step 4: Inverse dynamics analysis, please refer to [link / reference]. Figure 7In the diagram, "Inverse Dynamics" represents the inverse dynamics solution tool. To use the inverse dynamics solution tool, you need to first import the "Inverse Dynamics Settings File" into the solution tool. The inputs to the inverse dynamics solution tool are the "scaled model" obtained from the scaling tool in step 2, the "trajectory motion file calculated by inverse kinematics" obtained from the inverse kinematics solution tool in step 3, and the "experimentally measured reaction force data". The output is the "data file calculated by inverse dynamics". From the data file, you can obtain data such as joint torques, which can be used for muscle injury analysis.
[0067] Step 5: Static optimization calculation of muscle strength and muscle activation level, please refer to [link / reference]. Figure 8 In the diagram, "Static Optimization" represents the Static Optimization Tool. To use the Static Optimization Tool, you need to import the "Static Optimization Tool Settings File" first. The inputs to the Static Optimization Tool are the "scaled model" obtained from the scaling tool in step 2, the "trajectory motion file calculated by inverse kinematics" obtained from the inverse kinematics calculation tool in step 3, and the "reaction force data measured in experiments". The outputs are "muscle activation degree calculated by static optimization" and "muscle force calculated by static optimization", which are used for muscle injury analysis.
[0068] Step 6: Muscle damage analysis, using the data obtained in steps 3-5 to assess the risk of muscle damage.
[0069] In summary, addressing the issues of high risk and lack of standardization in existing live-body experiments, this invention innovatively integrates dummy impact test data with the OpenSim simulation platform. The neck motion trajectory parameters obtained from dummy testing are used as boundary conditions, acquired by collecting raw time series of displacement, velocity, and acceleration data from the dummy's head-neck reference points. The imported musculoskeletal model is scaled according to standardized dummy dimensions, specifically the neck geometry parameters of a Hybrid III 50th percentile male dummy. The scaling process includes: adjusting the intervertebral spacing based on the dummy's cervical spine length; adjusting muscle attachment point positions based on the dummy's neck cross-sectional dimensions; calculating joint loads through inverse kinematics school quasi-joint angles → inverse dynamics → static optimization calculation of muscle force distribution; and assessing the risk of impact-induced muscle injury based on peak muscle force, muscle activation timing, and energy absorption rate, combined with an injury threshold model. This method establishes a standardized analytical chain linking dummy experiments and musculoskeletal simulation for the first time, solving the problem of traditional methods being unable to quantify deep muscle damage under controllable conditions, and providing a highly reliable engineering analysis tool for automotive safety design and protective equipment optimization.
[0070] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0071] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0072] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.
Claims
1. A method for analyzing neck muscle impact injuries based on dummy experimental data, characterized in that, Includes the following steps: The neck motion trajectory parameters collected in the dummy impact test experiment will be used as the boundary conditions for the musculoskeletal model simulation. Import a pre-defined neck musculoskeletal model into the OpenSim platform, and after geometrically scaling the model according to the standardized dummy size, obtain the cervical joint angle, cervical joint load, and the activation and muscle force distribution of each muscle. Based on the extracted peak muscle strength, muscle activation sequence, and energy absorption rate per unit mass of muscle, the risk of impact muscle injury is assessed.
2. The method for analyzing neck muscle impact injuries based on dummy experimental data as described in claim 1, characterized in that: During the process of collecting neck motion trajectory parameters, the neck motion trajectory parameters are obtained by collecting the original time series of displacement, velocity and acceleration of the dummy's head-neck reference point.
3. The method for analyzing neck muscle impact injuries based on dummy experimental data as described in claim 2, characterized in that: During geometric scaling, the standardized dummy size is based on the neck geometry parameters of the 50th percentile male Hybrid III dummy. The scaling process includes: adjusting the intervertebral spacing of the model based on the dummy's cervical spine length; and adjusting the muscle attachment point positions based on the cross-sectional dimensions of the dummy's neck.
4. The method for analyzing neck muscle impact injuries based on dummy experimental data as described in claim 3, characterized in that: When obtaining the activation level and muscle strength distribution of each muscle, a static optimization algorithm is used to calculate the activation level and muscle strength distribution of each muscle. The objective function of the static optimization algorithm is: ； The constraints are: in: The activation level of the i-th muscle; This is the joint torque vector output in step 3; For muscle lever arm matrix; This is the muscle force vector.
5. The method for analyzing neck muscle impact injuries based on dummy experimental data as described in claim 4, characterized in that: When obtaining the unit mass muscle energy absorption rate, the unit mass muscle energy absorption rate is expressed as: ； In the formula, For the time window of impact; This is the muscle force vector; is a time function of muscle contraction velocity; m represents the mass of the target muscle.
6. The method for analyzing neck muscle impact injuries based on dummy experimental data as described in claim 5, characterized in that: When assessing the risk of impact-induced muscle injury, a muscle injury threshold model is used, wherein the muscle injury threshold model is expressed as: In the formula, F max F0 represents the maximum value of the muscle force time series, that is, the peak muscle force generated by a specific muscle within the time window of the impact. F0 represents the maximum isometric contractile force of the muscle.
7. The application of the neck muscle impact injury analysis method based on dummy experimental data as described in any one of claims 1-6, characterized in that: The results of the injury risk assessment can be applied to the optimization of design parameters for automotive seat safety systems or sports protective gear.
8. A neck muscle impact injury analysis system based on dummy experimental data, used to execute the neck muscle impact injury analysis method based on dummy experimental data as described in claim 1, characterized in that, The system includes: The data processing module is used to take the neck motion trajectory parameters collected in the dummy impact test experiment as the boundary conditions for the musculoskeletal model simulation. The feature extraction module is used to import a preset neck muscle and skeleton model into the OpenSim platform, and after geometrically scaling the model according to the standardized dummy size, obtain the cervical joint angle, cervical joint load, and the activation degree and muscle force distribution of each muscle. The risk assessment module is used to assess the risk of impact muscle injury based on the extracted peak muscle strength, muscle activation sequence, and energy absorption rate per unit mass of muscle.