Joint deformation fitting measuring device with spider web structure and measuring method

Abstract

The application discloses a joint deformation fitting measuring device with a spider web structure and a measuring method, breaks through the limitation of traditional static measurement, adopts a spider web structure arrangement combining point sensors and linear sensors, each detection point can independently perceive local deformation and stress change, reflects the deformation and stress condition of the joint part in different directions under each action, realizes partition measurement, overcomes the defect that the traditional overall area measurement cannot refine the joint area deformation, meanwhile, the flexible material is fitted to the human skin surface, ensures that the natural activity of the human body is not affected in the measuring process, and the joint movement state is intuitively displayed through an angle curve, a pressure heat map and a statistical chart, a scientific basis is provided for structure looseness design of the joint area of the professional workwear, the joint part of the workwear is better fitted to the action characteristics of the human body under the premise of ensuring protection and durability, wearing comfort is improved, and scientific data support is provided for optimizing the workwear pattern design.

Description

Technical Field

[0001] This invention belongs to the field of occupational workwear and human motion monitoring technology, specifically involving a joint deformation fitting measurement device and measurement method with a spider web-like structure. Background Technology

[0002] In many industries, workers often need to maintain a single posture or repeatedly perform the same actions for extended periods, such as carrying, assembling, or standing. Existing tooling mostly uses fixed sizes and preset patterns, making it impossible to adjust to the worker's body characteristics or adapt to the comfort needs of different body types or work conditions. Especially at joints, such as the knees, elbows, and shoulders, existing tooling lacks real-time monitoring of the range of motion and stress, resulting in the inability to obtain crucial posture and stress data.

[0003] Traditional tooling measurements primarily rely on static anthropometric measurements and standard size charts. Key dimensions such as shoulder width, chest circumference, waist circumference, arm length, and leg length are obtained using tools like measuring tapes and calipers, or standard sizes are established based on large-sample population data. Pattern design is then performed using two-dimensional cutting and human proportion coefficients. However, these static measurement methods have significant limitations: static dimensions cannot capture the spatial changes of key joints such as the knee, elbow, and shoulder joints during bending, extension, and rotation; they cannot display local pressure or strain conditions, making it difficult to guide the design of structural looseness or elasticity in key areas of the tooling. Summary of the Invention

[0004] The purpose of this invention is to provide a joint deformation fitting measurement device and method with a spider web-like structure. It addresses the shortcomings of existing technologies that cannot measure joint deformation and local stress in real time, continuously and fittingly. By arranging detection components (detection points and detection lines) in the joint area of ​​the human body, dynamic monitoring of the joint area under different movement and posture amplitudes can be achieved, thereby obtaining accurate deformation amplitude and stress distribution information, and realizing the monitoring of deformation and stress of key joints.

[0005] To solve the above technical problems, the following technical solution is adopted:

[0006] A spiderweb-like joint deformation fitting measurement device includes a spiderweb-shaped detection component attached to a human joint, conforming to the unevenness of the joint skin surface in the initial natural standing state. The detection component includes detection points and detection lines. The detection points are electromyographic sensors, and the detection lines are stretchable sensors. The electromyographic sensors are connected to each other through the stretchable sensors to form the spiderweb-like detection component. The electromyographic sensors and the stretchable sensors are used to collect local deformation and force at the joint.

[0007] Furthermore, the detection component includes a central intersection point, which serves as the starting point for the stretchable sensor and the electromyography (EMG) sensor. Radially arranged stretchable sensors extend outward from the central intersection point, with the extension direction of each stretchable sensor connected to the EMG sensor, forming a sensor assembly layer. Starting from the EMG sensor, the stretchable sensors and EMG sensors are arranged at intervals outward, continuing to form the sensor assembly layer. This sensor assembly layer constitutes a radial-annular interlaced, spiderweb-like structure.

[0008] Furthermore, based on the physiological morphology and range of motion of different joints, the number of sensors in each sensor combination layer is increased or decreased, and the number of layers in the sensor combination layer is increased or decreased.

[0009] A measurement method for a spiderweb-structure-inspired joint deformation fitting measurement device includes the following steps:

[0010] (1) Preparation of the test subjects;

[0011] (2) Detection component arrangement: Detection components are attached to the joints of the person being tested, and an XYZ spatial coordinate system is established;

[0012] (3) Dynamic measurement: The subject performs bending and twisting movements at the corresponding joints, including cyclic and continuous unidirectional flexion and unidirectional twisting of the elbow, knee and ankle. The detection components undergo corresponding deformation synchronously, and the electromyography sensor and the tensile strain sensor generate displacement and stress changes accordingly. Data is collected at a high sampling frequency.

[0013] (4) Data storage and analysis: a. Joint angle change calculation; b. Detection point displacement calculation; c. Overall deformation description of the detection component as the joint skin deforms; d. Local strain calculation.

[0014] After optimization, in step (1), the person being tested wears close-fitting and elastic clothing to reduce the interference of external clothing on the sensor fit and joint movement, and to ensure that the body remains in a natural standing position.

[0015] After optimization, in step (2), an XYZ spatial coordinate system is established: the center intersection point of the detection component in its initial state is taken as the origin of the XYZ coordinate axis, a radial direction is taken as the X-axis, the direction perpendicular to the X-axis is taken as the Y-axis, and the direction perpendicular to the entire detection component and passing through the origin is taken as the Z-axis, thus forming an XYZ spatial coordinate system; a short-term static calibration is performed before measurement to match the initial signal of the sensor with the natural posture and determine the initial quantities of the XYZ coordinates.

[0016] After optimization, the formula for calculating the joint angle change in step (4)a is:

[0017] in, , Let be the vector of the two detection points at time t.

[0018] After optimization, the formula for calculating the spatial displacement of the detection point in the XYZ coordinate system in step (4)b is as follows:

[0019]

[0020] in, Let be the coordinates of the i-th detection point at time t; The initial static position is given; the local deformation and deformation trajectory can be calculated using this formula.

[0021] After optimization, in step (4)c, the overall deformation of the detection component with joint skin deformation is described by matrix using the coordinates of each electromyography sensor, as shown below:

[0022]

[0023] Where N is the total number of nodes. This formula is used for visualization and simulation analysis.

[0024] After optimization, in step (4)d, the formula for calculating the tensile or compressive strain of the stretchable sensor is:

[0025]

[0026] in, Let i be the real-time distance between the two detection points i and j. The initial distance is used; this formula is used to generate local pressure or stretching thermograms.

[0027] The above technical solution has the following beneficial effects:

[0028] The spiderweb-like detection component of this invention consists of an electromyography (EMG) sensor (for point measurement) and a stretchable sensor (for line measurement). The stretchable sensor is arranged in a radial and annular grid pattern, with EMG sensors positioned at the intersections to collect deformation and local pressure during joint bending or stretching. The stretchable strain sensor deforms with joint movement, ensuring measurement accuracy and conforming to the skin.

[0029] The measurement method and device of this invention break through the limitations of traditional static measurement. They employ a spiderweb structure arrangement combining point and line sensors, allowing each detection point to independently sense local deformation and stress changes. This reflects the deformation and stress conditions of the joint in different directions under various movements, enabling zoned measurement and overcoming the shortcomings of traditional whole-area measurement which cannot refine the deformation of joint areas. Simultaneously, the flexible material conforms to the surface of human skin, ensuring that the measurement process does not affect the body's natural movements. Furthermore, the joint movement status is visually displayed through angle curves, pressure thermograms, and statistical charts, providing a scientific basis for the structural looseness design of joint areas in workwear. This allows workwear joints to better conform to human movement characteristics while ensuring protection and durability, improving wearing comfort and providing scientific data support for optimizing the design of workwear patterns. Attached Figure Description

[0030] The present invention will be further described below with reference to the accompanying drawings:

[0031] Figure 1 A schematic diagram of the overall layout of the spider web-like structure measuring device;

[0032] Figure 2 A schematic diagram showing the installation of the spiderweb-like measuring device at the joint.

[0033] Figure 3 A schematic diagram of the deformation and stress-strain of the joint of the spider web-like structure measuring device.

[0034] Figure 4 A schematic diagram of the spatial layout coordinate system for a spiderweb-like measuring device;

[0035] Figure 5 A schematic diagram illustrating the principle of monitoring joint bending deformation displacement and stress distribution;

[0036] Figure 6 This is a schematic diagram illustrating the principle of monitoring joint torsional deformation displacement and stress distribution. Detailed Implementation

[0037] This invention aims to provide a joint deformation fitting measurement device and method with a spider web-like structure. By arranging detection components (detection points and detection lines) in the joint area of ​​the human body, dynamic monitoring of the joint area under different movement and posture amplitudes can be achieved, thereby obtaining accurate deformation amplitude and force distribution information, and realizing the monitoring of deformation and force of key joints.

[0038] The present invention will be described in detail below with reference to specific embodiments:

[0039] like Figure 1As shown in Figure 6, a joint deformation fitting measurement device with a spider web-like structure includes a spider web-like detection component for signal acquisition, a wireless data acquisition board for signal storage, and an external receiving device for data analysis.

[0040] Multiple spiderweb-like detection components are arranged around the joints of the human body. When the body moves, the joints undergo bending, twisting, and other deformations, and the detection components attached to the joints deform accordingly. Because the amplitude and angle of the deformation on the joint surface are different, the degree and direction of pressure on the point-like and line-like areas of the detection components are also different, presenting different levels of signal feedback, thereby realizing the dynamic detection of joint deformation and force.

[0041] The detection component includes detection points and detection lines. The detection points are electromyography (EMG) sensors, and the detection lines are stretchable sensors. The EMG sensors are connected to each other via the stretchable sensors, forming a spiderweb-like detection component. The EMG sensors and stretchable sensors are used to collect local deformation and force at the joint. The detection component is attached to the human joint, conforming to the unevenness of the skin surface of the joint in the initial natural standing state. The stretchable sensors are made of flexible, bendable, and stretchable materials to ensure that they remain in close contact with the skin surface even during large-scale joint movements, without affecting the body's natural activities.

[0042] like Figure 1 As shown, in the detection component, the central intersection point is denoted as O, serving as the starting point for the stretchable sensor and the electromyography (EMG) sensor. Radially arranged stretchable sensors extend outward from the central intersection point O. The first stretchable sensor is denoted as A1, and an EMG sensor Aa is connected to it in its extension direction. The next stretchable sensor in the clockwise direction is denoted as A2, and its corresponding EMG sensor is denoted as Ab, and so on, forming a ring of sensor combination layers composed of stretchable sensors and EMG sensors. Furthermore, Aa, Ab, Ac… are also connected using stretchable sensors. Starting from the EMG sensor in this sensor combination layer, stretchable sensors and EMG sensors are arranged outward at intervals, forming several other sensor combination layers. These sensor combination layers form a radial-ring interlaced spiderweb-like structure. For example, a stretchable sensor extending outward from EMG sensor Aa in a ring direction is denoted as B1, and its end is connected to EMG sensor Bb, and so on, forming an arrangement of B2, B3… and Bc, Bd… By combining the aforementioned radial and annular sensors, a spiderweb-like structure is formed, with the central intersection point O as the starting point. Each electromyography (EMG) sensor is located at the intersection of the stretchable sensors, enabling precise acquisition of local deformation and force at key joint locations. In the aforementioned detection component, adjacent EMG sensors on different radial lines within the same sensor assembly layer are connected using stretchable sensors.

[0043] The spiderweb-like distribution of the detection components can be optimized according to the physiological morphology and range of motion of different joints, such as increasing or decreasing the number of sensors in each layer (from A1-A8 / Aa-Ah design to A1-An / Aa-An), increasing or decreasing the number of sensor arrangement layers (An): to ensure that high sensitivity deformation response and signal stability can still be maintained under large joint movement or complex torsion.

[0044] The wireless data acquisition board connects to sensors to receive physical changes (such as deformation and stress tension) collected by the sensors, converts them into electrical signals, and stores the processed data for subsequent reading and analysis. The external receiving device is the data terminal of the measurement device of this invention. By analyzing the data stored on the wireless data acquisition board, it is responsible for displaying, storing, and analyzing the deformation and stress data collected at the joint, generating visualized information, including joint angle change curves, pressure heat maps, data statistical charts, and trend analysis.

[0045] The method for measuring joint deformation using the aforementioned spiderweb-structure-inspired joint deformation fitting measuring device includes the following steps:

[0046] 1. Preparation of the test subject

[0047] The subjects wore close-fitting and elastic clothing to reduce interference from external clothing on the sensor fit and joint movement, and to ensure that the body remained in a natural standing position.

[0048] 2. Arrangement of detection components

[0049] Spiderweb-like detection components are attached to key joint areas of the subject (such as the knee, hip, elbow, and shoulder joints), ensuring a conformal fit to the natural contours of the skin at these joints. The initial center point O of the detection components is designated as the origin O of the XYZ coordinate system. The direction A1-Aa-B1-... is denoted as the X-axis. Taking an arrangement of eight radial lines as an example, the direction perpendicular to it, A3-Ac-B3-..., is denoted as the Y-axis. The axis perpendicular to the overall spiderweb sensor and passing through the origin O is denoted as the Z-axis, forming an XYZ spatial coordinate system. A short-term static calibration is performed before measurement to match the initial signals of each sensor with the natural posture, determining the initial values ​​of the XYZ coordinates and ensuring the accuracy of subsequent dynamic measurements.

[0050] 3. Dynamic measurement

[0051] The test subjects performed flexion and twisting movements at the corresponding joints, including cyclic and continuous unidirectional flexion and twisting of the elbows, knees, and ankles.

[0052] The detection components attached to the joint surface undergo corresponding deformations, resulting in minute displacements and stress changes in the electromyography sensor and the stretchable sensor. Differences in the amplitude, direction, and angle of deformation on the joint skin surface lead to varying mechanical loads felt at different detection points, thus generating differentiated signal feedback.

[0053] by Figure 2 and Figure 3 Taking elbow joint movement as an example, the center point of the detection component is point O, which is the origin of the XYZ coordinate system. The direction A1-Aa-B1-... is denoted as the X-axis, and A3-Ac-B3-... is denoted as the Y-axis. As the elbow flexes, since Aa, Ab, ..., Ah are attached to the skin and connect A1, A2, ..., A8, A1, A2, ..., A8 are subjected to the stretching effect of the elbow skin deformation. Simultaneously, because the local deformation of the skin is not uniform, the degree of stretching force experienced by A1, A2, ..., A8 is not a uniform change, but varies depending on the location of A1 and the differences between A1, A2, ... . High sampling frequency is used for data acquisition to ensure the capture of rapid changes and instantaneous stress peaks during the movement.

[0054] 4. Data storage and analysis

[0055] After the test is completed, the data is received and stored by the wireless data acquisition board. After receiving the data, the external receiving device can display, store, and visualize the data.

[0056] When a human joint undergoes bending, twisting, or other movements, the detection component deforms accordingly, including minute displacements of the skin surface, stretching, and torsion. The detection component's coordinate points in the XYZ coordinate system undergo spatial displacement. The deformation amplitude, direction, and angle vary in different areas of the joint skin, resulting in different local pressure or stress states felt by the detection points and detection lines. The change in its spatial position over time is visually represented by the XYZ coordinate system, and the corresponding joint angle change formula is:

[0057] in, , Let be the vector of the two detection points at time t.

[0058] The formula for the spatial displacement of the detection point in the XYZ coordinate system is:

[0059] in, Let be the coordinates of the i-th detection point at time t; The initial static position is given; the local deformation and deformation trajectory can be calculated using this formula.

[0060] Using the coordinates of each detection point, the overall deformation of the entire spiderweb-like sensor structure as the joint skin deforms can be described by a matrix, as shown below:

[0061] Where N is the total number of nodes. This formula is used for visualization and simulation analysis.

[0062] The above design differs from traditional methods that treat the entire joint or limb region as a single measurement unit. This invention employs a zoned measurement strategy, enabling segmented point-to-point measurements at key joint locations. Flexible sensors are arranged in a spiderweb structure: the intersection of each radial and annular stretchable sensor forms an independent detection node, each capable of independently sensing local deformation and pressure. Due to the flexible and independent structural design between nodes, the deformation of one node does not affect the measurement results of other nodes, working synchronously with the linear detection arrangement. This allows for independent measurement of each detection point while reflecting the overall regional deformation and stress changes of the joint. The tensile or compressive strain formula of the stretchable strain sensor, described by XYX spatial coordinates, is as follows:

[0063] in, Let i be the real-time distance between the two detection points i and j. The initial distance is used; this formula is used to generate local pressure or stretching thermograms.

[0064] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of the present invention.

Claims

1. A joint deformation fitting measurement device with a spider web-like structure, characterized in that: The device includes a spiderweb-like detection component that is attached to a human joint, conforming to the unevenness of the skin surface of the joint in a natural standing initial state. The detection component includes detection points and detection lines. The detection points are electromyography (EMG) sensors, and the detection lines are stretchable sensors. The EMG sensors are connected to each other through the stretchable sensors to form the spiderweb-like detection component. The EMG sensors and the stretchable sensors are used to collect local deformation and force at the joint.

2. The joint deformation fitting measurement device with a spider web-like structure according to claim 1, characterized in that: The detection component includes a central intersection point, which serves as the starting point for the stretchable sensor and the electromyography sensor. The stretchable sensors are arranged radially outward from the central intersection point, and the extension direction of the stretchable sensors is connected to the electromyography sensor to form a sensor combination layer. Starting from the electromyography sensor, the stretching sensor and the electromyography sensor are arranged outward at intervals, and the sensor combination layer is formed outward. The sensor combination layer forms a radial-ring interlaced spider web-like structure.

3. The joint deformation fitting measurement device with a spider web-like structure according to claim 2, characterized in that: Based on the physiological morphology and range of motion of different joints, the number of sensors in each sensor combination layer is increased or decreased, and the number of layers in the sensor combination layer is increased or decreased.

4. The measurement method of the spiderweb-structure-inspired joint deformation fitting measurement device as described in claim 1, characterized in that... The process includes the following steps: (1) Preparation of the test subject; (2) Arrangement of the detection components: attach the detection components to the joints of the test subject and establish an XYZ spatial coordinate system; (3) Dynamic measurement: the test subject performs bending and twisting movements at the corresponding joints, including cyclic and continuous unidirectional flexion and unidirectional twisting of the elbow, knee, and ankle. The detection components undergo corresponding deformation synchronously, and the electromyography sensor and the tensile strain sensor generate displacement and stress changes accordingly. Data is collected at a high sampling frequency; (4) Data storage and analysis: a) Calculation of joint angle changes; b) Calculation of detection point displacement; c) Description of the overall deformation of the detection components as the joint skin deforms; d) Calculation of local strain.

5. The measurement method of the joint deformation fitting measurement device with a spider web-like structure according to claim 4, characterized in that: In step (1), the person being tested wears close-fitting and elastic clothing to reduce the interference of external clothing on the sensor fit and joint movement, and to ensure that the body remains in a natural standing position.

6. The measurement method of the joint deformation fitting measurement device with a spider web-like structure according to claim 4, characterized in that: In step (2), an XYZ spatial coordinate system is established: the center intersection point of the detection component in its initial state is taken as the origin of the XYZ coordinate axis, a radial direction is taken as the X-axis, the Y-axis is perpendicular to the X-axis, and the Z-axis is perpendicular to the entire detection component and passes through the origin, thus forming the XYZ spatial coordinate system; a short-term static calibration is performed before measurement to match the initial signals of each sensor with the natural posture and determine the initial quantities of the XYZ coordinates.

7. The measurement method of the joint deformation fitting measurement device with a spider web-like structure according to claim 6, characterized in that: The formula for calculating the change in joint angle in step (4)a is as follows: in, , Let be the vector of the two detection points at time t.

8. The measurement method of the joint deformation fitting measurement device with a spider web-like structure according to claim 6, characterized in that: The formula for calculating the spatial displacement of the detection point in the XYZ coordinate system in step (4)b is as follows: in, Let be the coordinates of the i-th detection point at time t; The initial static position is given; the local deformation and deformation trajectory can be calculated using this formula.

9. The measurement method of the joint deformation fitting measurement device with a spider web-like structure according to claim 6, characterized in that: In step (4)c, the overall deformation of the detection component as the joint skin deforms is described by a matrix using the coordinates of each electromyography sensor, as shown below: Where N is the total number of nodes; this formula is used for visualization and simulation analysis.

10. The measurement method of the joint deformation fitting measurement device with a spider web-like structure according to claim 5, characterized in that: In step (4)d, the formula for calculating the tensile or compressive strain of the stretchable sensor is: in, Let i be the real-time distance between the two detection points i and j. The initial distance is used; this formula is used to generate local pressure or stretching thermograms.

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