A method for constructing a motion biomechanics data package of a quadrupedal reptile

Abstract

The application discloses a kind of construction methods of four-footed creeping class animal's motion biomechanics data package, it is related to biological motion mechanics technical field. Including: selecting four-footed creeping class animal, and establishing the skeletal muscle model of selected four-footed creeping class animal, obtain the morphological data of animal;Kinematics experiment is carried out to four-footed creeping class animal, and obtains the motion biomechanics data;Motion biomechanics data is imported into skeletal muscle model and simulation, obtain motion biomechanics model and simulation data;Morphological data, motion biomechanics data, motion biomechanics model and simulation data are classified and imported into data package, and the construction of data package is completed.The application can accurately construct the motion biomechanics model of four-footed creeping animal;Through multi-sensor data acquisition and advanced data processing technology, subtle change of animal movement is captured, and high-precision motion biomechanics model is generated, to provide data support for bionic robot design and animal behavior research.

Description

Technical Field

[0001] This invention relates to the field of biomechanics, and more particularly to a method for constructing a biomechanical data package for quadrupedal crawling animals. Background Technology

[0002] With the rapid development of bionics, robotics, and biomechanics, studying the locomotion mechanisms of animals in nature and applying them to engineering has become an important interdisciplinary research field. Among tetrapods, creeping animals (such as crocodiles and lizards) exhibit unique locomotion patterns. Compared to animals that stand upright or run, creeping animals rely on more complex ground contact methods, coordination of limbs and trunk, and adaptability to different terrains. This unique locomotion pattern provides rich inspiration for the field of bionics, especially in the design of quadrupedal bionic robots and automated systems.

[0003] In current technologies, biomimetic robots are mostly modeled after humans or upright-walking animals, focusing on research into bipedal or quadrupedal bipedal locomotion. However, the locomotion characteristics of creeping animals, such as flexible trunk movements, large-angle joint flexion, and complex friction and contact behaviors with the ground, make it difficult for traditional dynamic models and data packages based on upright locomotion to accurately simulate the locomotion patterns of creeping animals. Currently, research on the kinematics and dynamics of creeping animals still faces the following technical bottlenecks:

[0004] Lack of systematic biomechanical data: Existing research has only sporadically studied the tissue structure, locomotion, or biomechanics of a particular type of creeping animal, lacking comprehensive and systematic research data on their physiological structure, locomotion, and biomechanics. This data gap results in a limited understanding of the kinematic characteristics of creeping animals, making it difficult to provide sufficient data support for the design of biomimetic robots.

[0005] Limitations of existing models: Although various models have been proposed for the locomotion behavior of crawling animals, these models are mostly based on simplified two-dimensional analysis and fail to fully consider the complexity of three-dimensional locomotion and the dynamic interactions between joints, trunk, and muscles. Furthermore, these models often neglect dynamic parameters such as muscle strength, joint angles, and velocity changes during movement, and cannot accurately reflect the true biomechanical characteristics of the locomotion.

[0006] The Needs of Bionic Robot Design: For the design of bionic robots, especially quadrupedal bionic robots, accurate biomechanical data packages can not only improve the accuracy of motion control, but also optimize motion structures, reduce energy consumption, and enhance adaptability in complex terrains during the design process. Therefore, constructing a systematic, comprehensive, and high-precision biomechanical data package for crawling animals is of great significance for bionic robot design.

[0007] Therefore, proposing a method for constructing a biomechanical data package for the movement of quadrupedal crawling animals, which can collect and analyze the movement data of crawling animals, and thus provide accurate and reliable dynamic models for biomimetic robots, automated systems and biomechanical research, is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] In view of this, the present invention provides a method for constructing a biomechanical data package of quadrupedal crawling animals, which can accurately construct a biomechanical model of quadrupedal crawling animals; through multi-sensor data acquisition and advanced data processing technology, it can capture subtle changes in animal movement and generate a high-precision biomechanical model, providing data support for biomimetic robot design and animal behavior research.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A method for constructing a biomechanical data package for the movement of a quadrupedal reptile includes the following steps:

[0011] S1. Select a quadrupedal reptile and establish a skeletal and muscular model of the selected quadrupedal reptile to obtain the animal's morphological data;

[0012] S2. Conduct kinematic experiments on the quadrupedal reptiles in S1 to obtain kinematic data;

[0013] S3. Import the biomechanical data from S2 into the musculoskeletal model in S1 for simulation to obtain the biomechanical model and simulation data.

[0014] S4. Import the morphological data from S1, the kinematic data from S2, and the biomechanical model and simulation data from S3 into the data package to complete the construction of the data package.

[0015] Optionally, a skeletal and muscular model of a quadrupedal reptile is established in S1, including:

[0016] S101. Obtain the bone density and 3D model of the animal, and use computer software to assist in the calculation of the physical quantities of the bone.

[0017] S102. Confirm the type of joint movement, degree of freedom, axis of rotation, and relative spatial coordinates between bones;

[0018] S103. Obtain the animal's muscle parameters, including geometric parameters and muscle physiological parameters;

[0019] S104. Construct a skeletal muscle model based on the data obtained from S101-S103.

[0020] Optionally, the physical quantities of the skeleton in S101 include: center of mass and inertia tensor.

[0021] Optionally, the geometric parameters in S103 include: the proximal attachment point of the muscle relative to the bone, the distal attachment point, the geometry, the line of action, and the distribution path; the physiological parameters of the muscle include: the optimal fiber length of the muscle, the pennate angle of the muscle at the optimal fiber length, the maximum isometric contractile force of the muscle, the maximum contraction speed of the muscle, and the relaxation length of the tendon.

[0022] Optionally, the specific content of S2 is as follows:

[0023] An experimental platform simulating the horizontal / sloping movement environment of natural terrain was constructed to test the locomotion strategies adopted by quadrupedal crawling animals;

[0024] The experiment used a high-speed motion capture camera array on the experimental platform and attached markers to the quadrupedal reptiles to acquire motion data.

[0025] Mechanical data of quadrupedal crawling animals at different stages of movement were acquired using mechanical sensors on the experimental platform.

[0026] The obtained motion data and force data are synchronized and analyzed to form motion biomechanics data.

[0027] Optionally, the high-speed motion capture camera array uses video frames as the smallest time unit to capture animal motion data and gait parameters from multiple directions. The array typically consists of two to six cameras attached to markers on quadrupedal creepers to acquire motion data. The arrangement principles of the camera array include:

[0028] (1) Adjust the camera position and angle to ensure that the cameras cannot see each other and that the light spots formed by the cameras are not in the working area;

[0029] (2) Ensure that key parts of the animal are in the field of view of at least two cameras when the animal moves within the experimental area;

[0030] (3) The experimental area should be located in the center of the camera frame, rather than at the edge;

[0031] (4) All reflective objects in the camera frame, such as metal and glass, should be removed or covered.

[0032] Optionally, the mechanical sensor can be a 1D, 3D, or 6D force sensor, depending on the requirements. The force sensor can be attached to the animal, or one or more sensors can be arranged in an array to form an experimental path to obtain mechanical data of different stages of movement of the quadrupedal crawling animal. The obtained motion data and force data are synchronized and analyzed to form motion mechanical data.

[0033] Optionally, the specific content of S3 is as follows:

[0034] S301. Import motion data and force data into the skeletal muscle model;

[0035] S302. Determine the degree of matching between the two. If the simulation results do not match the existing kinematic experimental data, modify, add to or subtract from the original musculoskeletal model, or check the motion data and discard pathological data until the motion data matches the musculoskeletal model.

[0036] S303. Import the motion data into the model for simulation to obtain the joint angles;

[0037] S304. Import the ground reaction force data into the model for simulation to obtain the joint torque.

[0038] Optionally, the specific content of S4 is as follows:

[0039] The morphological data of quadrupedal creepers were imported into the kinematic data package. The morphological data included external size and skeletal dimensions.

[0040] The biomechanical data of quadrupedal animals were imported into the kinematic data package. The biomechanical data included kinematic data and dynamic data.

[0041] The biomechanical model and simulation data of quadrupedal crawling animals were imported into the biomechanical data package to obtain the biomechanical data package of quadrupedal crawling animals.

[0042] Optional kinematic data include: stride length, stride width, stride speed, stride frequency, stride length, stance phase, and swing phase in different gait states; joint angles, joint angular velocities, trunk posture, and gait symmetry.

[0043] Dynamic data: Ground reaction force.

[0044] Compared with the prior art, the method for constructing a biomechanical data package for a quadrupedal creeping animal provided by the present invention has the following beneficial effects:

[0045] It can collect and analyze the movement data of crawling animals, thereby providing accurate and reliable dynamic models for biomimetic robots, automated systems and biomechanical research; dynamic models and data packages based on traditional upright movement are difficult to accurately simulate the movement patterns of crawling animals. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0047] Figure 1 This is a flowchart of a method for constructing a biomechanical data package for a quadrupedal crawling animal, as disclosed in this invention.

[0048] Figure 2 A screenshot of the interface for importing the 3D model obtained after CT scanning disclosed in this invention into a 3D modeling software.

[0049] Figure 3 This is a schematic diagram of the terrestrial substrate crawling experimental platform for quadrupedal reptiles disclosed in this invention;

[0050] Figure 4 This is the skeletal muscle model disclosed in this invention. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0053] See Figure 1 The image shows a method for constructing a biomechanical data package for a quadrupedal crawling animal, as disclosed in this invention, comprising the following steps:

[0054] S1. Select a quadrupedal reptile and construct a skeletal and muscular model of the selected quadrupedal reptile (see [reference]). Figure 4 (As shown), obtain morphological data of the animal;

[0055] S2. Conduct kinematic experiments on the quadrupedal reptiles in S1 to obtain kinematic data;

[0056] S3. Import the biomechanical data from S2 into the musculoskeletal model in S1 for simulation to obtain the biomechanical model and simulation data.

[0057] S4. Import the morphological data from S1, the kinematic data from S2, and the biomechanical model and simulation data from S3 into the data package to complete the construction of the data package.

[0058] Furthermore, a skeletal and muscular model of a quadrupedal reptile is established in S1, including:

[0059] S101. Obtain the bone density and 3D model of the animal through anatomical data, CT scans, structured light scans, and literature review, and obtain the physical quantities of the bone through computer software-assisted calculations.

[0060] S102. Confirm the type of joint movement, degree of freedom, axis of rotation, and relative spatial coordinates between bones;

[0061] S103. Obtain the muscle parameters of the animal, including geometric parameters and muscle physiological parameters, through anatomical data, MRI, literature review, etc.

[0062] S104. Construct a skeletal muscle model based on the data obtained from S101-S103.

[0063] Furthermore, the physical quantities of the skeleton in S101 include: center of mass, inertial tensor, etc.

[0064] Furthermore, the geometric parameters in S103 include: the proximal attachment point of the muscle relative to the bone, the distal attachment point, the geometry, the line of action, and the distribution path; the physiological parameters of the muscle include: the optimal fiber length of the muscle, the pennate angle of the muscle at the optimal fiber length, the maximum isometric contractile force of the muscle, the maximum contractile speed of the muscle, and the relaxation length of the tendon.

[0065] Specifically, in S1, CT images of the animal are obtained through CT or Micro-CT scans. These images are then imported into Mimics to reconstruct a 3D skeletal model. Furthermore, the CT data, after density calibration (using materials of known density as a reference), provides the physical density of the bone (in g / cm³). 3 ).

[0066] The structured light 3D reconstruction of the dissected animal skeleton yields a 3D model of the skeleton. The mass of the skeleton is obtained by sampling or weighing the entire skeleton. The volume of the skeleton is obtained by using the displacement method (if there are large cavities inside the skeleton, the cavities should be connected to the outside). The bone density can also be obtained according to the formula density = mass / volume.

[0067] After obtaining the 3D model and density of the skeleton, the skeleton can be regarded as a rigid body in physics. The skeleton model is imported into 3D modeling software to obtain some physical parameters of the skeleton: center of mass and tensor matrix.

[0068] Perform CT scans, Micro-CT scans, or dissections on animal joints to preliminarily determine the type, degrees of freedom, axis of rotation, and spatial coordinates of the joint kinematic pairs between bones.

[0069] Muscle parameters of animals are obtained through anatomical data, MRI, and literature review. These parameters include:

[0070] Geometric parameters: proximal attachment point of muscle relative to bone, distal attachment point, geometry, line of action, and distribution path;

[0071] Physiological parameters of muscles: based on the Hill muscle model, including optimal fiber length, pennation angle at optimal fiber length, maximum isometric force, maximum contraction velocity, and tendon slack length.

[0072] Furthermore, the specific content of S2 is as follows:

[0073] Building an experimental platform in a simulated environment (see) Figure 3 (As shown), to test the locomotion strategies adopted by quadrupedal creepers in different terrain environments;

[0074] The experiment used a high-speed motion capture camera array on the experimental platform and attached markers to the quadrupedal creeper to acquire motion data. The high-speed motion capture camera array captured the animal's motion data and gait parameters from multiple directions, with video frames as the smallest time unit.

[0075] The experimental platform also includes a force sensor, which can be selected as a 1D, 3D, or 6D force sensor depending on the requirements. The force sensor can be attached to the animal, or one or more sensors can be arranged in an array to form an experimental path. The force sensor on the experimental platform is used to obtain mechanical data of different stages of movement of quadrupedal crawling animals.

[0076] The obtained motion data and force data are synchronized and analyzed to form motion biomechanics data.

[0077] Specifically, the experimental platform must first consider safety, minimizing harm to animals during the experiment. Hard objects such as fences and barriers should be used to restrict the animals' movement space, while soft objects such as sponge mats and foam blocks should be used to reduce injuries caused by falls or slips.

[0078] Before the experiment, reflective markers were attached to key areas of the experimental animals, such as joints and midline.

[0079] The experimental platform includes a high-speed motion capture camera array, typically consisting of two to six cameras. The principles for arranging the camera array include:

[0080] (1) Adjust the camera position and angle to ensure that the cameras cannot see each other and that the light spots formed by the cameras are not in the working area;

[0081] (2) Ensure that key parts of the animal are in the field of view of at least two cameras when the animal moves within the experimental area;

[0082] (3) The experimental area should be located in the center of the camera frame, rather than at the edge;

[0083] (4) All reflective objects in the camera frame, such as metal and glass, should be removed or covered.

[0084] After the camera array is set up, the cameras should be calibrated. Camera calibration includes the following steps:

[0085] (1) Set the camera frame rate to 50fps. The LED light intensity and threshold can be adjusted appropriately to ensure that there are bright spots on the working plane and no interference points in the camera lens. Ensure that all four cameras can see the three marker points of the calibration rod in the working space, and that the marker points do not block each other in any one camera. Shoot approximately 1000 frames of video data and save it in AVI format. Record this as Video 1.

[0086] (2) Place the coordinate stage stationary in the workspace (see Figure 3 (As shown), determine the world coordinate system of the workspace. Capture 1 frame of video data and save it as AVI format. Record this as Video 2.

[0087] (3) Import Video 1 and Video 2 into the corresponding program processing scripts respectively, and track the marker points in all cameras in each frame. The point markers in Video 2 are in the order of the origin X, Y, Z.

[0088] (4) After marking, export the data into two Excel files. Import the two Excel files into the corresponding program processing script to calculate the calibration result. If the calibration result score is too high, it means that the calibration result error is large and recalibration is required.

[0089] After the camera array is calibrated, video frames are used as the smallest unit of time to capture animal movement data from multiple angles, including gait parameters such as walking cycle, stride length, cadence, stance phase, and swing phase. More specific and digitized movement data is obtained by attaching reflective balls to key areas of the animal as markers.

[0090] Force sensors can be attached to an animal or formed by an array of one or more sensors to measure force data at different stages of the animal's movement.

[0091] Before using the force sensor, it should be calibrated so that the contact surface of the force sensor is horizontal. Then, gently place standard weights within the range on the force sensor one by one, record the data, export it, and compare it with the calculated value. If the error is large, compensation is required to ensure measurement accuracy.

[0092] The obtained motion data and force data are synchronized and analyzed to form motion biomechanics data.

[0093] Furthermore, the specific content of S3 is as follows:

[0094] S301. Import motion data and force data into the skeletal muscle model;

[0095] S302. Determine the degree of matching between the two. If the simulation results do not match the existing kinematic experimental data, modify, add to or subtract from the original musculoskeletal model, or check the motion data and discard pathological data until the motion data matches the musculoskeletal model.

[0096] S303. Import the motion data into the model for simulation to obtain the joint angles;

[0097] S304. Import the ground reaction force data into the model for simulation to obtain the joint torque.

[0098] Furthermore, the specific content of S4 is as follows:

[0099] The morphological data of quadrupedal creepers were imported into the kinematic data package. The morphological data included external size and skeletal dimensions.

[0100] The biomechanical data of quadrupedal animals were imported into the kinematic data package. The biomechanical data included kinematic data and dynamic data.

[0101] The biomechanical model and simulation data of quadrupedal crawling animals were imported into the biomechanical data package to obtain the biomechanical data package of quadrupedal crawling animals.

[0102] Morphological data for tetrapods include:

[0103] External dimensions: length, width, height, snout-anal length; dimensions of different parts: head length, neck length, body length, tail length, upper arm length, forearm length, thigh length, lower leg length, foot length, foot thickness, claw length, claw width.

[0104] Skeletal dimensions: Skull length, skull width, skull height; Spine length, spine width, spine height; Rib length, rib width, rib height; Sternum length, sternum width, sternum height; Scapula length, scapula width, scapula height.

[0105] Humerus length, humerus width, humerus height, forearm bone length, forearm bone width, forearm bone height, hand bone length, hand bone width, hand bone height, ilium length, ilium width, ilium height, ischium length, ischium width, ischium height, pubis length, pubis width, pubis height, femur length, femur width, femur height, tibia length, tibia width, tibia height, foot bone length, foot bone width, foot bone height.

[0106] Further kinematic data include: stride length, stride width, stride speed, stride frequency, stride length, stance phase, and swing phase in different chronotypes; joint angles, joint angular velocities, trunk posture, and gait symmetry;

[0107] Dynamic data: Ground reaction force (moment).

[0108] Import the quadrupedal animal simulation model and data into the sports biomechanics data package. The simulation model and data include: a skeletal muscle model built with Opensim and matching sports biomechanics data, which can perform simulations and output simulation data. Model motion simulation data includes: joint angles, joint angular velocities, joint angular accelerations, body posture, stride length, stride width, stride speed; joint torques, ground reaction forces, friction, impulse; muscle activation levels, muscle length changes, and muscle forces.

[0109] In one specific embodiment, taking the crocodile—one of the representative quadrupedal reptiles—as an example, a relatively complete biomechanical data package for movement was constructed according to the above method. The specific content is as follows:

[0110] S1 establishes a skeletal and muscular model of a quadrupedal reptile to obtain morphological data of the animal, including:

[0111] Five juvenile crocodiles, measuring 320±20 mm in length and 110±10 mm in width, were selected. After anesthesia, they underwent whole-body CT scans using a small CT scanner. The CT images were imported into Mimics, and a 3D skeletal model was reconstructed. Furthermore, the CT data, after density calibration (using materials of known density as a reference), provides the physical density of the bones (in g / cm³). 3 ).

[0112] After obtaining the 3D model and density of the skeleton, the skeleton can be regarded as a rigid body in physics. Import the skeleton model into 3D modeling software, see [link / reference]. Figure 2 As shown, some physical parameters of the skeleton are obtained: centroid and tensor matrix.

[0113] After modeling and analyzing CT images of the crocodile joints, the type, degrees of freedom, rotation axis, and spatial coordinates of the joint kinematic pairs between bones were preliminarily confirmed.

[0114] The muscle parameters of the crocodile were obtained through dissection and literature review. These parameters include:

[0115] Geometric parameters: proximal attachment point of muscle relative to bone, distal attachment point, geometry, line of action, distribution path;

[0116] Physiological parameters of muscles: based on the Hill muscle model, including optimal fiber length, pennation angle at optimal fiber length, maximum isometric force, maximum contraction velocity, and tendon slack length.

[0117] S2 conducted kinematic experiments on tetrapods to obtain kinematic data, including:

[0118] A rigid-based crawling experimental platform was constructed to study the terrestrial nature of crocodiles.

[0119] The crawling experimental platform includes a high-speed motion capture camera array, see [link / reference] Figure 3 As shown, it includes:

[0120] (1) Four high-speed motion capture cameras with a frame rate of 30-360 FPS, a resolution of 1664×1088, and grayscale color;

[0121] (2) A 20-port PoE switch and several PoE optical cables are used for power supply, signal transmission and synchronization between cameras.

[0122] (3) One host computer for displaying, debugging and saving data;

[0123] The crawling experimental platform includes a force acquisition array (see...) Figure 3 (As shown), including:

[0124] (1) An array of 18 three-dimensional force sensors, with a single sensor range of 2N and an accuracy of 0.5%FS;

[0125] (2) NI's data acquisition card, and data processing, display and storage are performed using a host computer program written in LabVIEW;

[0126] (3) The rotating pairs at both ends of the force array plane can tilt the force array plane from 0 to 180° to simulate different slopes.

[0127] After determining the equipment for the experimental platform, proceed with the setup and calibration of the equipment:

[0128] To ensure the safety of the crocodiles crawling on the experimental platform and to minimize the harm caused to them during the experiment, hard objects such as fences and barriers were used to restrict the crocodiles' movement space, while soft objects such as sponge mats and foam blocks were used to reduce injuries caused by falls and slips.

[0129] The principles for arranging camera arrays include:

[0130] (1) Adjust the camera position and angle to ensure that the cameras cannot see each other and that the light spots formed by the cameras are not in the working area;

[0131] (2) Ensure that key parts of the crocodile are visible in the field of view of at least two cameras when the crocodile moves within the experimental area;

[0132] (3) The experimental area should be located in the center of the camera frame, rather than at the edge;

[0133] (4) All reflective objects in the camera frame, such as metal and glass, should be removed or covered.

[0134] After the camera array is set up, the cameras should be calibrated. Camera calibration includes the following steps:

[0135] (1) Set the camera frame rate to 50fps. The LED light intensity and threshold can be adjusted appropriately to ensure that there are bright spots on the working plane and no interference points in the camera lens. Ensure that all four cameras can see the three markers on the calibration rod in the working space. Do not allow the markers to block each other in any one camera. Shoot about 1000 frames of video data and save it in AVI format. Record it as Video 1.

[0136] (2) Determine the world coordinate system of the workspace through the standard calibration block; capture 1 frame of video data and save it as AVI format; record it as video 2.

[0137] (3) Import Video 1 and Video 2 into the corresponding data processing scripts respectively, and track the marker points in all cameras in each frame. The point markers in Video 2 are in the order of origin, X, Y, Z.

[0138] (4) After marking, export the data into two Excel files. Import the two Excel files into the corresponding data processing script to calculate the calibration results. If the calibration result has a large error, you need to return to the calibration process (1) to recalibrate or adjust the camera placement.

[0139] To simulate real natural scenes, 800-grit sandpaper is attached to the surface of the force sensor to increase friction.

[0140] Force sensor calibration: With the contact surface of the force sensor horizontal, gently place a standard weight within the range on each force sensor in turn, record the data, export it and compare it with the calculated value. If the error is large, compensation is required to ensure measurement accuracy.

[0141] The obtained motion data and force data are synchronized and analyzed to form motion biomechanics data.

[0142] Specifically, the biomechanical data is imported into a crocodile skeletal muscle model for simulation, resulting in a biomechanical model and simulation data, including:

[0143] Scaling: Import the skeletal muscle model into OpenSIM and adjust the model's pose to be similar to the model's pose in real-world experiments; adopt a measurement-based scaling mode, that is, determine the scaling factor of the body parts by comparing the distance measurements between the model's marker points and the corresponding experimental marker points.

[0144] Click to run and save the scaled new model.

[0145] Inverse kinematics: Inverse kinematics is the study of the motion of an object without considering the forces and torques generated during the motion. The purpose of inverse kinematics is to estimate the joint angles of a specific object based on experimental data. It minimizes the error of marker points by using weighted least squares optimization, and calculates the required joint angles at each time step by setting the weight of each marker point.

[0146] Inverse dynamics: Inverse kinematics studies the forces and torques involved in the motion of an object. By estimating the forces and torques for a specific motion, it infers how muscles are utilized during movement. The joint angles solved by inverse kinematics and the ground reaction force data collected by the force array in actual experiments are imported into the model for simulation, calculating the net action reaction force and net torque for each joint.

[0147] S3 imports morphological data, movement data, kinematic models, and simulation data of quadrupedal reptiles into the data package in a categorized manner. Taking crocodiles as an example, the data includes:

[0148] Import the crocodile morphological data into the kinematic data package. The morphological data includes:

[0149] External dimensions: length, width, height, snout-anal length; dimensions of different parts: head length, neck length, body length, tail length, upper arm length, forearm length, thigh length, lower leg length, foot length, foot thickness, claw length, claw width.

[0150] Skeletal dimensions: Skull length, skull width, skull height; Spine length, spine width, spine height; Rib length, rib width, rib height; Sternum length, sternum width, sternum height; Scapula length, scapula width, scapula height.

[0151] Humerus length, humerus width, humerus height, forearm bone length, forearm bone width, forearm bone height, hand bone length, hand bone width, hand bone height, ilium length, ilium width, ilium height, ischium length, ischium width, ischium height, pubis length, pubis width, pubis height, femur length, femur width, femur height, tibia length, tibia width, tibia height, foot bone length, foot bone width, foot bone height.

[0152] The crocodile's biomechanical data was imported into a kinematics data package. The biomechanical data included:

[0153] Kinematic data: stride length, stride width, stride speed, stride frequency, stride length, stance phase, and swing phase in different gait states; joint angles, joint angular velocities, trunk posture, and gait symmetry;

[0154] Dynamic data: Ground reaction force (moment).

[0155] Import the crocodile simulation model and data into the sports biomechanics data package. The simulation model and data include:

[0156] Opensim provides a skeletal muscle model with matching kinematic data, which can be used for simulation and output simulation data.

[0157] Model motion simulation data: joint angles, joint angular velocity, joint angular acceleration, body posture, stride length, stride width, stride speed; joint torque, ground reaction force, friction, impulse; muscle activation level, muscle length change, muscle force.

[0158] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0159] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. 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 invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for constructing a biomechanical data package for the movement of a quadrupedal reptile, characterized in that, Includes the following steps: S1. Select a quadrupedal reptile and establish a skeletal and muscular model of the selected quadrupedal reptile to obtain the animal's morphological data; S2. Conduct kinematic experiments on the quadrupedal reptiles in S1 to obtain kinematic data; S3. Import the biomechanical data from S2 into the musculoskeletal model in S1 for simulation to obtain the biomechanical model and simulation data. S4. Import the morphological data from S1, the kinematic data from S2, and the biomechanical model and simulation data from S3 into the data package to complete the construction of the data package.

2. The method for constructing a biomechanical data package for a quadrupedal crawling animal according to claim 1, characterized in that, S1 establishes a skeletal and muscular model of a quadrupedal reptile, including: S101. Obtain the bone density and 3D model of the animal, and use computer software to assist in the calculation of the physical quantities of the bone. S102. Confirm the type of joint movement, degree of freedom, axis of rotation, and relative spatial coordinates between bones; S103. Obtain the animal's muscle parameters, including geometric parameters and muscle physiological parameters; S104. Construct a skeletal muscle model based on the data obtained from S101-S103.

3. The method for constructing a biomechanical data package for a quadrupedal crawling animal according to claim 2, characterized in that, The physical quantities of the skeleton in S101 include: center of mass and inertial tensor.

4. The method for constructing a biomechanical data package for a quadrupedal creeper according to claim 2, characterized in that, The geometric parameters in S103 include: the proximal attachment point of the muscle relative to the bone, the distal attachment point, the geometry, the line of action, and the distribution path; the physiological parameters of the muscle include: the optimal fiber length of the muscle, the pennate angle of the muscle at the optimal fiber length, the maximum isometric contractile force of the muscle, the maximum contractile speed of the muscle, and the relaxation length of the tendon.

5. The method for constructing a biomechanical data package for a quadrupedal crawling animal according to claim 1, characterized in that, The specific content of S2 is as follows: An experimental platform simulating natural horizontal / sloping terrain was constructed to test the locomotion strategies adopted by quadrupedal creepers in different terrain environments. The experiment used a high-speed motion capture camera array on the experimental platform and attached markers to the quadrupedal reptiles to acquire motion data. Mechanical data of quadrupedal crawling animals at different stages of movement were acquired using mechanical sensors on the experimental platform. The obtained motion data and force data are synchronized and analyzed to form motion biomechanics data.

6. The method for constructing a biomechanical data package for a quadrupedal crawling animal according to claim 5, characterized in that, The high-speed motion capture camera array captures animal motion data and gait parameters from multiple angles, using video frames as the smallest time unit. Camera arrays typically consist of two to six cameras attached to the bodies of quadrupedal reptiles to acquire motion data. The principles for arranging camera arrays include: (1) Adjust the camera position and angle to ensure that the cameras cannot see each other and that the light spots formed by the cameras are not in the working area; (2) Ensure that key parts of the animal are in the field of view of at least two cameras when the animal moves within the experimental area; (3) The experimental area should be located in the center of the camera frame, rather than at the edge; (4) All reflective objects in the camera frame, such as metal and glass, should be removed or covered.

7. The method for constructing a biomechanical data package for a quadrupedal crawling animal according to claim 5, characterized in that, The aforementioned mechanical sensor can be selected as a 1D, 3D, or 6D force sensor according to requirements; the force sensor can be attached to the animal, or one or more sensors can be arranged into an array to form an experimental path to obtain mechanical data of different stages of movement of quadrupedal crawling animals; the obtained motion data and force data are synchronized and analyzed to form motion mechanical data.

8. The method for constructing a biomechanical data package for a quadrupedal crawling animal according to claim 1, characterized in that, The specific content of S3 is as follows: S301. Import motion data and force data into the skeletal muscle model; S302. Determine the degree of matching between the two. If the simulation results do not match the existing kinematic experimental data, modify, add to or subtract from the original musculoskeletal model, or check the motion data and discard pathological data until the motion data matches the musculoskeletal model. S303. Import the motion data into the model for simulation to obtain the joint angles; S304. Import the ground reaction force data into the model for simulation to obtain the joint torque.

9. The method for constructing a biomechanical data package for a quadrupedal creeping animal according to claim 1, characterized in that, The specific content of S4 is as follows: The morphological data of quadrupedal creepers were imported into the kinematic data package. The morphological data included external size and skeletal dimensions. The biomechanical data of quadrupedal animals were imported into the kinematic data package. The biomechanical data included kinematic data and dynamic data. The biomechanical model and simulation data of quadrupedal crawling animals were imported into the biomechanical data package to obtain the biomechanical data package of quadrupedal crawling animals.

10. A method for constructing a biomechanical data package for a quadrupedal creeper according to claim 9, characterized in that, Kinematic data include: stride length, stride width, stride speed, stride frequency, stride length, stance phase, and swing phase in different gait states; joint angles, joint angular velocities, trunk posture, and gait symmetry; Dynamic data: Ground reaction force.

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