A method, apparatus, computer equipment, and medium for evaluating ergonomics in microgravity environments.

Abstract

This application relates to a method, apparatus, computer equipment, and medium for ergonomic evaluation in microgravity environments. The method includes: reconstructing a parametric human body model from a human image based on a SMPL model; obtaining the model's posture parameters from the parametric human body model; converting the model's posture parameters from axis angles to Euler angles to obtain Euler angle set data for the posture to be evaluated; calculating the difference between this Euler angle set data and the benchmark Euler angle set data; determining the joint comfort score based on the Euler angle difference and a given scoring framework table; and obtaining the ergonomic evaluation result under microgravity conditions. This invention, based on reconstructing human posture using a three-dimensional parametric model, can significantly reduce the cost of human anthropometric measurements. Using Euler angles for ergonomic evaluation more accurately expresses joint movements and has better semantic representation, corresponding to each degree of freedom of the joint. This method is applicable to the evaluation of human working postures in microgravity environments, exhibiting strong adaptability and high practicality.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a method, apparatus, computer equipment, and storage medium for evaluating the ergonomics of a microgravity environment. Background Technology

[0002] In the era of long-term manned stays on space stations, astronauts need to perform various tasks in the microgravity environment of space for extended periods. Therefore, the comfort of astronauts' working conditions has a significant impact not only on their physical and mental health but also on the successful completion of missions. Human body 3D reconstruction is one of the hot topics in computer vision in recent years, and various research results in this field, such as SMPL, have achieved widespread application value in many industrial sectors. Ergonomics (or human factors engineering) is a newly emerging interdisciplinary field in recent years, whose research aims to make human work more efficient, safe, and comfortable.

[0003] Three commonly used methods for ergonomics assessment based on human posture observation are Repid Upper Limb Assessment (RULA), Repid Entire Body Assessment (REBA), and the Owako Working Posture Analyzing System (OWAS). However, existing ergonomics assessment methods such as RULA and REBA are designed for analyzing and assessing the posture of workers in ground gravity environments. In microgravity environments, the kinematic and physiological characteristics of the human body change significantly, and comfortable postures such as neutral positions also change. These methods, which are commonly used in ground gravity environments, are no longer suitable. Directly applying them to ergonomics assessments in microgravity environments will result in significant assessment errors.

[0004] Secondly, methods like RULA and REBA assess human posture by using the projection angles of each joint's posture onto the anatomical plane. While this method is relatively simple and saves effort in anthropometry, it's not very accurate in representing human posture. There are two reasons for this: First, projection angles on a two-dimensional plane sometimes cannot fully represent the three-dimensional posture of the human body. Although for multi-degree-of-freedom joints like the shoulder and hip joints, their three-dimensional coordinates can be constrained using projection angles on two or more planes, for single-degree-of-freedom joints like the elbow and knee joints, since their rotation axes are not always perpendicular to the various anatomical planes, a single projection angle cannot accurately represent the joint's rotation. Using multiple projection angles introduces redundancy and increases the complexity of the assessment. Therefore, existing technologies suffer from poor adaptability. Summary of the Invention

[0005] Therefore, it is necessary to provide a method, apparatus, computer equipment, and storage medium for evaluating the ergonomics of a microgravity environment that can more accurately express joint rotation, in order to address the aforementioned technical problems.

[0006] A method for evaluating ergonomics in a microgravity environment, the method comprising:

[0007] Human images in a microgravity environment are captured by cameras deployed from multiple perspectives. A parameterized human model is reconstructed based on the human images using the SMPL model. The model pose parameters are then obtained based on the parameterized human model.

[0008] The model's posture parameters are converted from axis angles to Euler angles to obtain Euler angle set data for the posture to be evaluated; the Euler angle set data for the posture to be evaluated can express the joint rotation of the current human posture.

[0009] A baseline Euler angle ensemble is constructed based on the known neutral body position information in a microgravity environment;

[0010] The Euler angle difference of each joint is determined based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data, and the joint comfort score is determined based on the Euler angle difference and the pre-given scoring framework table.

[0011] The ergonomic evaluation results under microgravity environment are obtained based on the joint comfort score.

[0012] In one embodiment, the method further includes: acquiring the model attitude parameters; the model attitude parameters are axis angle data;

[0013] The rotation matrix is ​​obtained based on the axis angle data;

[0014] The rotation matrix is ​​converted into internal rotation Euler angles in zyx order, and the Euler angle set data of the attitude to be evaluated is obtained by solving.

[0015] In one embodiment, the method further includes: constructing a reference Euler angle set data based on the known neutral body position information in the microgravity environment; the reference Euler angle set data consists of the Euler angle data of each joint required for the SMPL model to transition from the default posture to the neutral body position in the microgravity environment.

[0016] In one embodiment, the method further includes: determining the Euler angle difference of each joint based on the Euler angle set data of the posture to be evaluated and the reference Euler angle set data;

[0017] The comfort score for each degree of freedom of the joint is determined based on the Euler angle difference and a pre-given scoring framework table.

[0018] The comfort scores of each degree of freedom of the joints are added together to obtain the joint comfort score; the joint comfort score includes: cervical joint, lumbar spine, shoulder joint, elbow joint, wrist joint, hip joint, knee joint and ankle joint.

[0019] In one embodiment, the method further includes: obtaining comfort scores for each part of the body based on the joint comfort score;

[0020] An overall posture score is obtained based on the comfort scores of each part of the body.

[0021] The posture comfort rating result is determined based on the overall posture score.

[0022] In one embodiment, the method further includes: constructing an upper limb assessment table, a neck, trunk, and lower limb assessment table;

[0023] The comfort scores for each part of the body are determined by looking up a table based on the joint comfort scores.

[0024] In one embodiment, the method further includes: reconstructing a parametric human model from the human image using the Multiview extension of SMPLify-X based on the SMPL model.

[0025] A microgravity environment ergonomics evaluation device, the device comprising:

[0026] The model pose parameter determination module is used to capture human images in a microgravity environment through cameras deployed from multiple perspectives, reconstruct a parameterized human model based on the SMPL model from the human images, and obtain model pose parameters based on the parameterized human model.

[0027] The Euler angle conversion module is used to convert the model posture parameters from axis angles to Euler angles to obtain Euler angle set data of the posture to be evaluated; the Euler angle set data of the posture to be evaluated can express the joint rotation of the current human posture.

[0028] The baseline determination module is used to construct a baseline Euler angle set data based on the known neutral body position information in the microgravity environment;

[0029] The joint comfort scoring module is used to determine the Euler angle difference of each joint based on the Euler angle set data of the posture to be evaluated and the benchmark Euler angle set data, and to determine the joint comfort score based on the Euler angle difference and a pre-given scoring framework table.

[0030] The ergonomics assessment module is used to obtain ergonomics assessment results under microgravity environment based on the joint comfort score.

[0031] A computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program performing the following steps:

[0032] Human images in a microgravity environment are captured by cameras deployed from multiple perspectives. A parameterized human model is reconstructed based on the human images using the SMPL model. The model pose parameters are then obtained based on the parameterized human model.

[0033] The model's posture parameters are converted from axis angles to Euler angles to obtain Euler angle set data for the posture to be evaluated; the Euler angle set data for the posture to be evaluated can express the joint rotation of the current human posture.

[0034] A baseline Euler angle ensemble is constructed based on the known neutral body position information in a microgravity environment;

[0035] The Euler angle difference of each joint is determined based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data, and the joint comfort score is determined based on the Euler angle difference and the pre-given scoring framework table.

[0036] The ergonomic evaluation results under microgravity environment are obtained based on the joint comfort score.

[0037] A computer-readable storage medium having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0038] Human images in a microgravity environment are captured by cameras deployed from multiple perspectives. A parameterized human model is reconstructed based on the human images using the SMPL model. The model pose parameters are then obtained based on the parameterized human model.

[0039] The model's posture parameters are converted from axis angles to Euler angles to obtain Euler angle set data for the posture to be evaluated; the Euler angle set data for the posture to be evaluated can express the joint rotation of the current human posture.

[0040] A baseline Euler angle ensemble is constructed based on the known neutral body position information in a microgravity environment;

[0041] The Euler angle difference of each joint is determined based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data, and the joint comfort score is determined based on the Euler angle difference and the pre-given scoring framework table.

[0042] The ergonomic evaluation results under microgravity environment are obtained based on the joint comfort score.

[0043] The aforementioned microgravity environment ergonomics assessment method, device, computer equipment, and storage medium reconstruct a parametric human body model from human images based on the SMPL model. The model's posture parameters are obtained from the parametric human body model. Axial angles are converted to Euler angles to obtain Euler angle set data for the posture to be evaluated. The difference between this Euler angle set data and the baseline Euler angle set data is calculated. Joint comfort scores are determined based on the Euler angle difference and a pre-defined scoring framework. The ergonomics assessment results under microgravity conditions are obtained based on the joint comfort scores. This invention, based on a three-dimensional parametric model to reconstruct human posture, significantly reduces the cost of human anthropometric measurements. Using Euler angles for ergonomics assessment more accurately expresses joint movements and provides better semantic representation, corresponding to each degree of freedom of the joint. This invention is applicable to the assessment of human working postures in a space microgravity environment. It can provide a basis for ensuring and improving the efficiency and comfort of astronauts' on-orbit work, as well as the human-centered design of space equipment system structures and functions. It can also provide a reference for future on-orbit human factors research on space stations. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating a microgravity environment ergonomics evaluation method in one embodiment;

[0045] Figure 2 This is a schematic diagram of the SMPL model and its joint definitions in one embodiment;

[0046] Figure 3 This is a schematic diagram illustrating three types of neck joint movement in one embodiment, wherein, Figure 3 (a) is a diagram illustrating neck flexion. Figure 3 (b) is a schematic diagram of horizontal neck rotation. Figure 3 (c) is a schematic diagram of lateral flexion of the neck;

[0047] Figure 4 This is a schematic diagram illustrating three forms of torso movement in one embodiment, wherein, Figure 4 (a) is a diagram of trunk flexion. Figure 4 (b) is a schematic diagram of horizontal rotation of the torso. Figure 4 (c) is a schematic diagram of trunk lateral flexion;

[0048] Figure 5 This is a schematic diagram illustrating three movement patterns of the shoulder joint in one embodiment, wherein, Figure 5 (a) is a schematic diagram of shoulder external rotation. Figure 5 (b) is a schematic diagram of shoulder horizontal adduction. Figure 5 (c) is intended to show the shoulder outwards;

[0049] Figure 6 This is a schematic diagram of elbow flexion in one embodiment;

[0050] Figure 7This is a schematic diagram of the wrist joint's two degrees of freedom and the forearm's rotational movement in one embodiment, wherein, Figure 7 (a) is a diagram of wrist flexion. Figure 7 (b) is a schematic diagram of wrist radial deviation. Figure 7 (c) is a schematic diagram of forearm rotation;

[0051] Figure 8 This is a schematic diagram illustrating three types of hip joint movement in one embodiment, wherein, Figure 8 (a) is a schematic diagram of hip flexion. Figure 8 (b) is a schematic diagram of hip external rotation. Figure 8 (c) Intended for external hip presentation;

[0052] Figure 9 This is a schematic diagram of knee flexion in one embodiment;

[0053] Figure 10 This is a schematic diagram illustrating three movement patterns of the ankle joint in one embodiment, wherein, Figure 10 (a) is a schematic diagram of ankle plantar flexion. Figure 10 (b) is a schematic diagram of outward rotation of the ankle joint. Figure 10 (c) is a schematic diagram of ankle inversion;

[0054] Figure 11 This is a structural block diagram of a microgravity environment ergonomics evaluation device in one embodiment;

[0055] Figure 12 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0057] In one embodiment, such as Figure 1 As shown, a method for evaluating ergonomics in a microgravity environment is provided, including the following steps:

[0058] Step 102: Capture human images in a microgravity environment using cameras deployed from multiple perspectives; reconstruct a parametric human model based on the human images using the SMPL model; and obtain the model's pose parameters based on the parametric human model.

[0059] SMPL is a parametric, vertex-based 3D human modeling tool capable of detailed modeling and animation simulation of human bodies of arbitrary shapes. It is also a learnable model, which can be trained to better fit human body shapes and poses. Compared to previous models such as SCAPE, SMPL demonstrates higher realism in reflecting changes in human body shape, has more control parameters, is more efficient in optimization, and can accommodate larger training sets. One key difference between SMPL and traditional hybrid skinning methods is that SMPL can learn the influence of pose on human body shape, resulting in more natural models that avoid strange deformations at joints.

[0060] The SMPL model defines 6890 vertices and 24 joints, of which 23 joints can change the shape of the human body, and the remaining root node controls the overall spatial position and rotation of the human body. The definitions of each joint in SMPL are as follows: Figure 2 As shown, Figure 2 The T-pose in the text is its standard template pose.

[0061] SMPLify-X is a method for fitting the SMPL-X model to the results of human joint detection on a single 2D RGB image. The SMPL-X model is a further improvement on the SMPL model, adding facial and hand models. However, since facial and hand keypoints are not involved in ergonomics evaluation, the SMPL model already meets the requirements. Furthermore, the SMPL model is optional in the SMPLify-X configuration; therefore, this invention still uses the SMPL model for reconstruction. The SMPL model itself provides the 3D coordinates of 24 joints. SMPLify-X reprojects these 3D joint coordinates onto a 2D image and fits them with the 2D joint coordinates obtained from the 2D human keypoint detection framework OpenPose. Simultaneously, it introduces body shape loss, pre-trained pose priors, and model collision / penetration penalties to obtain the SMPL parametric human model and its parameters on the fitted image. Since multi-view images can extract more comprehensive human pose features, the Multiview extension of SMPLify-X is used to fuse the 2D fitting results from multiple perspectives, resulting in a more accurate SMPL parametric human model.

[0062] Step 104: Convert the model attitude parameters from axis angles to Euler angles to obtain the Euler angle set data of the attitude to be evaluated.

[0063] The SMPL model uses axis angles to represent the rotation of each joint, while this patent uses Euler angles to represent joint rotation, thus requiring a conversion from axis angles to Euler angles.

[0064] The axis angle is expressed as a three-dimensional vector, which itself represents the direction of the rotation axis, and its magnitude represents the angle of rotation. Euler angles can also be represented by a three-dimensional vector, whose three elements represent the angles of three rotations, which occur in a certain order and around the axis of rotation. Since the axis angle is only equivalent to one rotation, it has a significant problem of ambiguity when expressing the rotation of joints with multiple degrees of freedom. Specifically, when the joint is in different motion states, its rotation axis direction needs to be recalculated, and the ergonomic evaluation strategy will also change accordingly. However, the internal rotation form of Euler angles, that is, three rotations occurring sequentially around the three coordinate axes of the motion coordinate system, if the motion coordinate system is set as a coordinate system fixed to the joint, then the relative positions of the rotation axes of these three Euler angles with respect to the joint are determined. It is evident that Euler angles have significant advantages over axis angles as a means of expressing joint rotation. Firstly, they express joint rotation more clearly and explicitly, possessing better semantic representation capabilities. For example, the three Euler angles of the shoulder joint can be expressed as internal and external rotation, horizontal abduction and adduction, and abduction and adduction. Secondly, the direction of the rotation axis and the relative position of the joint remain stable and unchanged. To a certain extent, each Euler angle can be considered independent, meaning its contribution to the ergonomics score is relatively independent. Therefore, the Euler angles of each rotation axis can be evaluated separately and then summarized to obtain the overall score of the joint.

[0065] Step 106: Construct a baseline Euler angle set data based on the known neutral body position information in the microgravity environment.

[0066] The ergonomic evaluation method designed in this invention sets the most comfortable posture with the lowest score (the lower the better) as the neutral body position in a microgravity environment, which is known information given by NASA in a test report in 2019.

[0067] Specifically, a set of Euler angles is used to represent the neutral body position, and this set of Euler angles is used as the benchmark for ergonomic evaluation. This set of Euler angles consists of the Euler angles of each joint required to transform from the default posture (T-posture) of the SMPL model to the neutral body position.

[0068] Step 108: Determine the Euler angle difference for each joint based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data, and determine the joint comfort score based on the Euler angle difference and the pre-given scoring framework table.

[0069] The greater the difference between the Euler angle of the joint being evaluated and the given Euler angle, the lower the joint comfort is considered, and the higher the score is given. The scoring framework was mainly established with reference to RULA and REBA.

[0070] Step 110: Obtain the ergonomics evaluation results under microgravity environment based on the joint comfort score.

[0071] The comfort scores for each part of the body are obtained based on the joint comfort scores; the overall posture score is obtained based on the comfort scores for each part of the body; and the posture comfort rating is determined based on the overall posture score.

[0072] In the aforementioned ergonomics assessment method for microgravity environments, a parametric human body model is reconstructed from human images based on the SMPL model. The model's posture parameters are obtained from the parametric human body model, and the posture parameters are converted from axis angles to Euler angles to obtain the Euler angle set data for the posture to be evaluated. The difference between this Euler angle set data and the baseline Euler angle set data is calculated. Based on the Euler angle difference and a pre-defined scoring framework, a joint comfort score is determined. The ergonomics assessment result under microgravity is obtained based on the joint comfort score. This invention, based on the reconstruction of human posture using a three-dimensional parametric model, can significantly reduce the cost of human anthropometric measurements. Using Euler angles for ergonomics assessment more accurately expresses joint movements and has better semantic representation, corresponding to each degree of freedom of the joint. This method is applicable to the assessment of human working postures in microgravity environments, providing a basis for ensuring and improving the efficiency and comfort of astronauts' on-orbit work, as well as the human-centered design of space equipment system structures and functions. It can also provide a reference for future on-orbit human factors research on space stations.

[0073] In one embodiment, the method further includes: obtaining model attitude parameters; the model attitude parameters are axis angle data; obtaining a rotation matrix based on the axis angle data; converting the rotation matrix into in-rotation Euler angles in zyx order, and solving for the Euler angle set data of the attitude to be evaluated.

[0074] Specifically, to convert axis angles to Euler angles, we can first convert the axis angles into rotation matrices, and then use the Rodriguez formula for the conversion:

[0075] R(k,θ)=Icosθ+sinθM+(1-cosθ)k·k T

[0076] Where R is the rotation matrix, I is the identity matrix, θ is the rotation angle, k is the unit vector of the rotation axis direction, and M is the cross product matrix corresponding to k.

[0077] Then, the rotation matrix is ​​converted into Euler angles. This method uses internal rotation Euler angles in the zyx order to represent the joint rotation. The rotation matrix corresponding to these Euler angles is:

[0078]

[0079] Therefore, based on the relationship between the elements of the rotation matrix and Euler angles, the following expression for solving Euler angles is obtained:

[0080]

[0081] In one embodiment, the method further includes: determining the Euler angle difference of each joint based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data; determining the comfort score of each degree of freedom of the joint based on the Euler angle difference and a pre-given scoring framework table; adding the comfort scores of each degree of freedom of the joint to obtain the joint comfort score; the joint comfort score includes: cervical joint, lumbar spine, shoulder joint, elbow joint, wrist joint, hip joint, knee joint and ankle joint.

[0082] Specifically, the assessment of the cervical joint corresponds to joint number 12 in the SMPL model. The three types of cervical joint movements are flexion and extension around the x-axis, horizontal rotation around the y-axis, and lateral flexion around the z-axis, as follows: Figure 3 As shown.

[0083] The detailed scoring criteria for the cervical joint are as follows:

[0084] (1) Flexion and extension

[0085] Forward bending 15°~35°: 1 point;

[0086] Forward flexion 35°–40° or 0–15°, backward extension 0–5°: 2 points;

[0087] Forward flexion 40°–45° or backward extension 5°–25°: 3 points;

[0088] Forward flexion 45°–50° or backward extension 25°–50°: 4 points.

[0089] (2) Lateral rotation

[0090] 0–15° on either side: 0 points;

[0091] 1 point for 15°–30° on either side;

[0092] 30°–45° on either side: 2 points;

[0093] 45° to 65° on either side: 3 points.

[0094] (3) Lateral flexion

[0095] 0–12° on either side: 0 points;

[0096] 1 minute for any side 12°–24°;

[0097] 24°–36° on either side: 2 points.

[0098] The total score for the cervical joint assessment is obtained by adding the scores for each degree of freedom. The total score for each joint is calculated in the same way.

[0099] Next is the assessment of the trunk, which involves three types of trunk movements: flexion-extension, lateral rotation, and lateral flexion around the x, y, and z axes, respectively. Figure 4 As shown.

[0100] Trunk movement is the result of coordinated operation of joints such as the thoracic and lumbar vertebrae. For simplicity, trunk movement is represented only by the rotation of the lumbar vertebrae, corresponding to joint number 3 in the SMPL model. The trunk assessment details are as follows:

[0101] (1) Flexion and extension

[0102] Forward flexion 0–13° or backward extension 0–5°: 1 point;

[0103] Forward flexion 13°–25° or 5°–10°: 2 points;

[0104] Forward flexion 25°–37° or 10°–15°: 3 points;

[0105] Forward flexion 37°–50° or 15°–20°: 4 points.

[0106] (2) Lateral rotation

[0107] 0~8°: 0 points;

[0108] 8°~16°: 1 minute;

[0109] 16°~24°: 2 minutes;

[0110] 24°~32°: 3 minutes.

[0111] (3) Lateral flexion

[0112] 0~8°: 0 points;

[0113] 8°~16°: 1 minute;

[0114] 16°~24°: 2 minutes;

[0115] 24°~30°: 3 minutes.

[0116] The shoulder joint has various movements, including internal and external rotation around the x-axis, horizontal abduction and adduction around the y-axis, and abduction and adduction around the z-axis. Figure 5 As shown.

[0117] The shoulder joint assessment method is as follows:

[0118] (1) Internal and external rotation

[0119] Internal rotation 0–27° or external rotation 0–5°: 0 points;

[0120] Internal rotation 27°~45° or external rotation 5°~20°: 1 point;

[0121] Internal rotation 45°~60° or external rotation 20°~35°: 2 points;

[0122] Internal rotation 60°~80° or external rotation 35°~40°: 3 points.

[0123] (2) Horizontal abduction and induction

[0124] Adduction 20°–60°: 1 minute;

[0125] Adduction 0°~20° or 60°~80°: 2 points;

[0126] Adduction 80°–100° or abduction 0–20°: 3 points;

[0127] Adduction 100°–120° or abduction 20–40°: 4 points;

[0128] Adduction 120°–140° or abduction 40–62°: 5 points;

[0129] (3) Outward expansion and inward contraction

[0130] Adduction 20°–70°: 0 points;

[0131] Adduction 0°~20° or 70°~90°, abduction 0~10°: 1 point;

[0132] Adduction 90°–110° or abduction 10°–40°: 2 points;

[0133] Adduction 110°~130° or abduction 40°~70°: 3 points;

[0134] Adduction 130°~150° or abduction 70°~90°: 4 points;

[0135] Next is the assessment of the elbow joint. Generally, the elbow joint only has one form of movement: flexion (e.g., Figure 6 As shown in the figure, in the SMPL model, elbow flexion and extension correspond to joints 18 and 19 rotating around the y-axis.

[0136] The elbow joint assessment method is as follows:

[0137] Flexion 70°~115°: 1 point;

[0138] Flexion 30°–70° or 115°–123°: 2 points;

[0139] Flexion 0–30° or 123°–130°, extension 0–10°: 3 points

[0140] like Figure 7As shown, the wrist joint has two degrees of freedom: radial or ulnar tilt around the y-axis and palmar or dorsiflexion around the z-axis. The movement around the x-axis is accomplished by the rotation of the radius and ulna, which results in the forearm rotating about itself. Strictly speaking, this is neither a degree of freedom of the wrist nor the elbow joint, but it can still be represented by the SMPL because each joint in the SMPL has three degrees of freedom. This does not completely match reality, although in reality, the elbow and wrist joints do not have a degree of freedom to rotate around the x-axis. Therefore, the angle of rotation of the forearm around the x-axis can be approximately represented by the Euler angle of the wrist joint rotation around the x-axis in the SMPL. For simplicity, the score of forearm rotation is included in the total score of the wrist joint assessment.

[0141] The wrist joint assessment method is as follows:

[0142] (1) Palmar flexion or dorsiflexion

[0143] Palmar flexion or dorsiflexion 0–23°: 1 minute;

[0144] Palmar flexion or dorsiflexion 23°–46°: 2 points;

[0145] Palmar flexion or dorsiflexion 46°–69°: 3 points.

[0146] (2) Radial or ulnar tilt

[0147] Radial tilt 0–9°, ulnar tilt 0–21°: 0 points;

[0148] Radial tilt 9°~18°, ulnar tilt 21°~43°: 1 point.

[0149] (3) Forearm rotation

[0150] Internal rotation 0–56°, external rotation 0–30°: 1 point;

[0151] Internal rotation 56°~85°, external rotation 30°~90°: 2 points.

[0152] The hip joint has three degrees of freedom: flexion and extension, internal and external rotation, and adduction and abduction (e.g., Figure 8 As shown in the figure, these correspond to joints 1 and 2 in the SMPL rotating around the x, y, and z axes, respectively.

[0153] The hip joint assessment method is established as follows:

[0154] (1) Flexion and extension

[0155] Forward flexion 25°~58°: 1 point;

[0156] Forward flexion 13°–25° or 58°–79°: 2 points;

[0157] Forward flexion 0–13° or 79°–100°: 3 points;

[0158] Extension 0-10°, flexion 100°-120°: 4 points.

[0159] (2) Internal and external rotation

[0160] Internal or external rotation 0–11°: 0 points;

[0161] Internal or external rotation 11°–22°: 1 point;

[0162] Internal or external rotation 22°–33°: 2 points.

[0163] (3) Inward and outward expansion

[0164] Abduction 0–20°, Adduction 0–10°: 0 points;

[0165] Abduction 20°–30°, adduction 10°–20°: 1 point;

[0166] Abduction 30°~40°, adduction 20°~30°: 2 points.

[0167] Knee joint ergonomics assessment methods:

[0168] The knee joint has only one degree of freedom: flexion and extension. Figure 9 As shown, this corresponds to joints 4 and 5 in SMPL rotating around the x-axis.

[0169] The knee joint assessment method is as follows:

[0170] Flexion 25°~65°: 0 points;

[0171] Flexion of 10°–25° or 65°–90°: 1 point;

[0172] Flexion 0–10° or 90°–115°: 2 points;

[0173] Hyperextension 0–10°, flexion 115°–140°: 3 points.

[0174] The ankle joint has three degrees of freedom: plantar flexion or dorsiflexion around the x-axis, internal and external torsion around the y-axis, and internal and external inversion around the z-axis. Figure 10 These represent the degrees of freedom of the right ankle joint (corresponding to joint 8 in the SMPL model).

[0175] The ankle joint assessment method is as follows:

[0176] (1) Plantar flexion or dorsiflexion

[0177] Plantar flexion 9°–27°: 0 points;

[0178] Plantar flexion 0–9° or 27°–33°, dorsiflexion 0–3°: 1 point;

[0179] Plantar flexion 33° to 40°, dorsiflexion 3° to 15°: 2 points.

[0180] (2) Internal and external twisting

[0181] Twist inward 0-10° or twist outward 0-13°: 0 points;

[0182] Twist inward 10°–20° or outward 13°–26°: 1 point;

[0183] Twist inward 20°~30° or outward 26°~40°: 2 points.

[0184] (3) Inversion and eversion

[0185] Inversion or eversion 0–14°: 0 points;

[0186] Inversion or eversion 14°–28°: 1 point

[0187] In one embodiment, the method further includes: constructing an upper limb assessment table, a neck, trunk, and lower limb assessment table; and determining the comfort score of each part of the body by looking up the table based on the joint comfort score.

[0188] Specifically, based on the joint assessment scores obtained above, and referring to the scoring tables of RULA and REBA, the following assessment methods for each body part and overall posture are established:

[0189] First, we can obtain the total score for the upper limbs by referring to Table 1. It can be seen that the lowest score is 1 point and the highest score is 9 points.

[0190] Table 1 Upper Limb Assessment Table

[0191]

[0192] Then, the total score for the neck, trunk, and lower limbs is obtained by referring to Table 2.

[0193] Table 2 Postural Assessment of Neck, Trunk, and Lower Limbs

[0194]

[0195] Finally, the scores in Table 1 and Table 2 are combined, and the final score is calculated using Table 3 as shown below.

[0196] Table 3 Overall Posture Assessment

[0197]

[0198] The final posture ergonomics assessment score was obtained. The following is a method for assessing posture levels based on this total score:

[0199] 1-2 points: Level 0, a relatively comfortable and ideal working posture;

[0200] 3-4 points: Level 1, slightly uncomfortable working posture, should not be maintained for a long time;

[0201] 5-7 points: Level 2, a work posture with strong discomfort, which should be corrected as soon as possible;

[0202] A score greater than 8 points: Level 3, a very uncomfortable working posture that is very likely to cause musculoskeletal diseases, and posture correction should be carried out immediately.

[0203] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0204] In one embodiment, such as Figure 11 As shown, a microgravity environment ergonomics evaluation device is provided, including: a model attitude parameter determination module 1102, an Euler angle conversion module 1104, a benchmark determination module 1106, a joint comfort scoring module 1108, and an ergonomics evaluation module 1110, wherein:

[0205] The model pose parameter determination module 1102 is used to capture human images in a microgravity environment through cameras deployed from multiple perspectives, reconstruct a parameterized human model based on the human images using the SMPL model, and obtain model pose parameters based on the parameterized human model.

[0206] Euler angle conversion module 1104 is used to convert the model posture parameters from axis angles to Euler angles to obtain Euler angle set data of the posture to be evaluated; the Euler angle set data of the posture to be evaluated can express the joint rotation of the current human posture;

[0207] The benchmark determination module 1106 is used to construct benchmark Euler angle set data based on the known neutral body position information in the microgravity environment;

[0208] The joint comfort scoring module 1108 is used to determine the Euler angle difference of each joint based on the Euler angle set data of the posture to be evaluated and the benchmark Euler angle set data, and to determine the joint comfort score based on the Euler angle difference and the pre-given scoring framework table.

[0209] The ergonomics assessment module 1110 is used to obtain ergonomics assessment results under microgravity environment based on joint comfort scores.

[0210] The Euler angle conversion module 1104 is also used to obtain model attitude parameters; the model attitude parameters are axis angle data; the rotation matrix is ​​obtained based on the axis angle data; the rotation matrix is ​​converted into internal rotation Euler angles in the zyx order, and the Euler angle set data of the attitude to be evaluated is obtained by solving.

[0211] The baseline determination module 1106 is also used to construct baseline Euler angle set data based on the known neutral body position information in the microgravity environment; the baseline Euler angle set data consists of the Euler angle data of each joint required for the SMPL model to be transformed from the default posture to the neutral body position in the microgravity environment.

[0212] The joint comfort rating module 1108 is also used to determine the Euler angle difference of each joint based on the Euler angle set data of the posture to be evaluated and the benchmark Euler angle set data; determine the comfort score of each degree of freedom of the joint based on the Euler angle difference and the pre-given rating framework table; add the comfort scores of each degree of freedom of the joint to obtain the joint comfort score; the joint comfort score includes: cervical joint, lumbar spine, shoulder joint, elbow joint, wrist joint, hip joint, knee joint and ankle joint.

[0213] The ergonomic assessment module 1110 is also used to obtain the comfort score of each part of the body based on the joint comfort score; to obtain the overall posture score based on the comfort score of each part of the body; and to determine the posture comfort rating result based on the overall posture score.

[0214] The ergonomics assessment module 1110 is also used to construct assessment tables for the upper limbs, neck, trunk, and lower limbs; and to determine the comfort scores of each part of the body by looking up the tables based on the joint comfort scores.

[0215] The model pose parameter determination module 1102 is also used to reconstruct a parametric human model from human images using the Multiview extension of SMPLify-X based on the SMPL model.

[0216] Specific limitations regarding the microgravity environment ergonomics evaluation device can be found in the limitations of the microgravity environment ergonomics evaluation method described above, and will not be repeated here. Each module in the aforementioned microgravity environment ergonomics evaluation device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0217] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 12As shown, the computer device includes a processor, memory, network interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements a microgravity environment ergonomics evaluation method. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0218] Those skilled in the art will understand that Figure 12 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0219] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement the steps in the above method embodiment.

[0220] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0221] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0222] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0223] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for evaluating ergonomics in a microgravity environment, characterized in that, The method includes: Human images in a microgravity environment are captured by cameras deployed from multiple perspectives. A parameterized human model is reconstructed based on the human images using the SMPL model. The model pose parameters are then obtained based on the parameterized human model. The model's posture parameters are converted from axis angles to Euler angles to obtain Euler angle set data for the posture to be evaluated; the Euler angle set data for the posture to be evaluated can express the joint rotation of the current human posture. A baseline Euler angle ensemble is constructed based on the known neutral body position information in a microgravity environment; The Euler angle difference of each joint is determined based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data, and the joint comfort score is determined based on the Euler angle difference and the pre-given scoring framework table. The ergonomic evaluation results under microgravity environment are obtained based on the joint comfort score.

2. The method according to claim 1, characterized in that, The model attitude parameters are converted from axis angles to Euler angles to obtain Euler angle set data for the attitude to be evaluated, including: Obtain the model attitude parameters; the model attitude parameters are axis angle data; The rotation matrix is ​​obtained based on the axis angle data; The rotation matrix is ​​converted into internal rotation Euler angles in zyx order, and the Euler angle set data of the attitude to be evaluated is obtained by solving.

3. The method according to claim 1, characterized in that, The construction of the baseline Euler angle set data based on the known neutral body position information in the microgravity environment includes: A baseline Euler angle set is constructed based on the known neutral body position information in the microgravity environment; the baseline Euler angle set consists of the Euler angle data of each joint required for the SMPL model to transition from the default posture to the neutral body position in the microgravity environment.

4. The method according to claim 1, characterized in that, Based on the Euler angle set data of the posture to be evaluated and the baseline Euler angle set data, the Euler angle difference of each joint is determined. Then, based on the Euler angle difference and a pre-given scoring framework, a joint comfort score is determined, including: The Euler angle difference of each joint is determined based on the Euler angle set data of the posture to be evaluated and the reference Euler angle set data. The comfort score for each degree of freedom of the joint is determined based on the Euler angle difference and a pre-given scoring framework table. The comfort scores of each degree of freedom of the joints are added together to obtain the joint comfort score; the joint comfort score includes: cervical joint, lumbar spine, shoulder joint, elbow joint, wrist joint, hip joint, knee joint and ankle joint.

5. The method according to claim 1, characterized in that, The ergonomic evaluation results under microgravity environment are obtained based on the joint comfort score, including: The comfort scores for each part of the body are obtained based on the joint comfort scores. An overall posture score is obtained based on the comfort scores of each part of the body. The posture comfort rating result is determined based on the overall posture score.

6. The method according to claim 5, characterized in that, The comfort scores for various parts of the body are obtained based on the joint comfort scores, including: Construct assessment forms for the upper limbs, neck, trunk, and lower limbs; The comfort scores for each part of the body are determined by looking up a table based on the joint comfort scores.

7. The method according to any one of claims 1 to 6, characterized in that, The parametric human model reconstructed from the human image based on the SMPL model includes: A parametric human model is reconstructed from the human image using the Multiview extension of SMPLify-X based on the SMPL model.

8. A microgravity environment ergonomics evaluation device, characterized in that, The device includes: The model pose parameter determination module is used to capture human images in a microgravity environment through cameras deployed from multiple perspectives, reconstruct a parameterized human model based on the SMPL model from the human images, and obtain model pose parameters based on the parameterized human model. The Euler angle conversion module is used to convert the model posture parameters from axis angles to Euler angles to obtain Euler angle set data of the posture to be evaluated; the Euler angle set data of the posture to be evaluated can express the joint rotation of the current human posture. The baseline determination module is used to construct a baseline Euler angle set data based on the known neutral body position information in the microgravity environment; The joint comfort scoring module is used to determine the Euler angle difference of each joint based on the Euler angle set data of the posture to be evaluated and the benchmark Euler angle set data, and to determine the joint comfort score based on the Euler angle difference and a pre-given scoring framework table. The ergonomics assessment module is used to obtain ergonomics assessment results under microgravity environment based on the joint comfort score.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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