Structured fabric manufacturing method, variable stiffness orthotic device, and variable stiffness method thereof

Abstract

The application provides a structured fabric manufacturing method, a variable rigidity orthopedic device and a variable rigidity method thereof, and specific steps of the structured fabric manufacturing method are as follows: selecting discrete particle units, establishing a structured fabric, testing the performance of the structured fabric, optimizing the discrete particle units, and manufacturing the structured fabric. The variable rigidity orthopedic device comprises an orthopedic device main body, a negative pressure control valve and a force sensing correction pad. The structured fabric wrapped by a closed space is arranged in the interior of the orthopedic device main body, the discrete particle units in the pressure area and the release area are arranged with the same or different structures and densities, the bottom of the negative pressure control valve is connected with the closed space in the interior of the orthopedic device main body, and the force sensing correction pad is arranged in the pressure area of the orthopedic device main body. The application realizes the bidirectional rigidity conversion between flexibility and rigidity through the antagonistic effect of the structured fabric under the action of negative pressure, so that the structured fabric realizes variable rigidity under the action of negative pressure, and the demand of the orthopedic device for flexible adaptation to the body and rigid support correction is met.

Description

Technical Field

[0001] This invention relates to the field of variable stiffness structural design technology, and to a method for manufacturing structured fabrics, a variable stiffness orthopedic device and a method for varying stiffness, particularly for use in orthopedic devices for scoliosis. Background Technology

[0002] Orthopedic treatment is based on biomechanical principles. By applying orthopedic forces to the ribs and iliac bones, the force is transmitted to the most severely affected area of ​​scoliosis, reducing the degree of spinal deformity and maintaining the optimal orthopedic state. It has now become an effective and mainstream method for treating scoliosis.

[0003] In a patent titled "A Variable Stiffness Orthosis," the orthosis's breathability and wearing comfort are improved by setting the same density for the rod structure in all contact areas with the human body, or by setting different densities for the rod structure in different contact areas. However, due to the local stiffness differences formed by rigid components with different stiffnesses, the mutual conversion between flexible conformal and rigid support in the contact area cannot be achieved.

[0004] In a patent application titled "A Spinal Orthopedic Device," the position of the tension band on the limiting slide and the tightening line can be adjusted to adapt to different correction positions. However, this method fails to address the problems of uncertain orthopedic effects and the tendency for the force application point to shift.

[0005] In the patent application titled "An Adjustable Scoliosis Orthosis and Its Method of Use," an airbag structure is used to more flexibly and conveniently apply force to localized areas of the body, thereby adjusting the corrective force at those areas. However, the main structure of this orthosis is made of rigid polymer material, which cannot meet the adjustment requirements for changing corrective needs.

[0006] In summary, existing orthotic structures cannot simultaneously meet the requirements of flexible adaptation to body shape and rigid support. In addition, some orthotics require adjustment capabilities. Therefore, this invention proposes a structured fabric manufacturing method, a variable stiffness orthotic device, and a variable stiffness method thereof. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides a method for manufacturing structured fabric, a variable stiffness orthopedic device, and a method for varying stiffness. By setting structured fabric inside the main body of the orthopedic device, the structured fabric is composed of a base layer and a functional layer made of discrete particle units. The parameters of the structured fabric are optimized according to the performance requirements of the structured fabric in the orthopedic process, thereby meeting the requirements of flexible adaptation to the body shape and rigid support capacity. The actual contact pressure during the orthopedic process is monitored through force-sensing correction pads, and the data is used to assist in timely adjustments to improve the accuracy of the orthopedic procedure.

[0008] This invention provides a method for manufacturing structured fabrics for orthopedic devices, comprising the following steps:

[0009] S1. Select discrete particle elements: Based on the requirements of contact and support stiffness in the pressure zone, select a three-dimensional element structure that simultaneously satisfies the mass, contact and stiffness conditions from the three-dimensional element structures to be selected, and obtain discrete particle elements using modeling software.

[0010] S2. Establishing a structured fabric: Based on the parameters of the discrete particle units obtained in step S1, the discrete particle units are connected into a base layer and a functional layer, and the base layer and the functional layer are connected to obtain a structured fabric that meets the bending stiffness and tensile strength of the flexible body.

[0011] S3. Test the properties of structured fabrics:

[0012] S31. Based on the data of the model to be corrected, adjust the shape of the structured fabric and apply pressure to the boundary of the structured fabric to perform a three-point bending simulation of the structured fabric.

[0013] S32. Collect the length, width and height values ​​of the structured fabric after deformation, and calculate the elastic bending modulus E of the structured fabric to obtain the bending resistance of the orthodontic body.

[0014] S33. Calculation of contact pressure P between discrete particle units in structured fabrics based on the discrete element method:

[0015] The expression for the normal stiffness of the discrete particle unit is:

[0016]

[0017] Where m1 and m2 are the masses of two adjacent particle units, E is the elastic modulus, v is Poisson's ratio, ρ is density, and l min The side length of the particle unit;

[0018] The expression for the tangential stiffness of the discrete particle unit is:

[0019]

[0020] Where m1 and m2 are the masses of two adjacent particle units, G is the shear modulus, ρ is the density, and l min The side length of the particle unit;

[0021] The expression for the contact pressure P between discrete particle units is:

[0022] P = kx

[0023] Where k is the contact stiffness and x is the displacement during the contact process;

[0024] S34. Compare the bending modulus E and contact pressure P obtained in steps S32 and S33 with the initial support force and orthotics force of the orthotine, and determine whether the performance of the structured fabric meets the requirements by combining the orthotics strength data and the data in the orthotics force database.

[0025] S4. Optimize discrete particle units: Extract the outline of discrete particle units, and optimize the size, shape and topology of discrete particle units based on the performance test results obtained in step S3, thereby enhancing the sliding characteristics between discrete particle units, enhancing the contact between discrete particle units, reducing the density of structured fabric, and increasing conformal flexibility while improving the stiffness of structured fabric after negative pressure.

[0026] The expression for the optimization model is:

[0027]

[0028] Where W is the total mass of the discrete particle element, t is the topology design variable of the discrete particle element, and t = (t1, t2, ..., t3). n ) T , ρ i Let l be the density of the i-th group of antagonistic rods. j Let A be the length of the j-th antagonistic rod. i Let i be the cross-sectional design variable for the i-th discrete particle element, i = 1, 2, ..., n. Let P be the upper limit of the cross-sectional design variables, P be the number of elements, and C be the shape design variables, where C = (C1, C2, ..., C...). f ) T , i = 1, 2, ..., n, j ∈ G i G i Let σ be the set of antagonistic rod numbers belonging to the i-th group. i , u k , These are the upper and lower limits of stress and displacement, respectively, σ jl Let u be the stress of the j-th antagonistic bar under the l-th working condition, where l = 1, 2, ..., 0. kl Let S be the k-th constrained displacement value under the l-th working condition, where k = 1, 2, ..., R, and S is the discrete set of the cross-sections of the discrete particle element. Here, denoted as the upper limit of shape variables, D as the discrete set of shape variables, H as the number of shape variables, n as the number of bar groups, O as the number of working cases, and R as the number of displacement constraints.

[0029] S5. Fabrication of structured fabric: Using relevant processes, based on the structure, density, and mechanical property parameters of the discrete particle units optimized in step S4, select materials that meet the performance parameters obtained in step S3 to print structured fabric.

[0030] Preferably, in step S1, the printing parameters of the three-dimensional unit structure include a key node wall thickness ≥ 0.6 mm, a minimum cutout hole diameter ≥ 1 mm, and a minimum wall thickness ≥ 0.4 mm.

[0031] Preferably, in step S1, the contact condition is surface contact, wherein the expression for the normal stress is:

[0032] σ=F N / A≤[σ]

[0033] The expression for shear stress is:

[0034] τ=F s / A≤[τ]

[0035] Among them, F N F is the normal force acting on an object. s Let A be the shear force acting on the object, A be the cross-sectional area of ​​the object, [σ] be the allowable stress, and [τ] be the allowable shear stress.

[0036] Preferably, in step S2, the base layer is a robust chain-like structure layer formed by rotating adjacent discrete particle units relative to each other by a certain angle and arranging all discrete particle units in parallel and interlocking; the functional layer is a structure layer obtained by setting a functional layer between adjacent base layers and rotating the discrete particle units located in the functional layer relative to the discrete particle units located in the base layer by a certain angle.

[0037] Preferably, in step S4, the optimized parameters include the size, structure, and density of the discrete particle units, the level of detail of the smooth surface of the discrete particle units, and the thickness and width of the antagonistic bars.

[0038] Preferably, in step S5, the material includes nylon plastic, TPU material, and alloy material.

[0039] A second aspect of the present invention provides a variable stiffness orthopedic device obtained using the aforementioned structured fabric manufacturing method for orthopedic devices, comprising an orthopedic body, a negative pressure control valve, a force-sensing corrective pad, and the structured fabric. A first mounting end and a second mounting end of the orthopedic body are respectively connected to the negative pressure control valve, the force-sensing corrective pad, and the tightening strap. The structured fabric is disposed inside the orthopedic body, which is divided into a pressure zone and a release zone according to orthopedic requirements. Force-sensing corrective pads are disposed on the inner surface of the pressure zone of the orthopedic body. The negative pressure control valve includes a pressure-sensing valve core and a valve cover, with the connecting end of the pressure-sensing valve core connected to the fixed end of the valve cover. The structured fabric includes discrete particle units and a closed-space covering layer, with the discrete particle units located inside the closed-space covering layer, and adjacent discrete particle units connected by antagonistic rods.

[0040] Preferably, the discrete particle unit includes hollow spheres, regular octahedrons, and regular hexahedrons; the cross-sectional shape of the antagonistic rods in the structured fabric includes triangles, rhombuses, and ellipses.

[0041] Preferably, the pressure sensing valve core includes a pressure sensing module, a spring, and a sealing diaphragm; the force sensing correction pad is internally equipped with a deformable thin film pressure sensor.

[0042] A third aspect of the present invention provides a variable stiffness method using the aforementioned variable stiffness straightening device, comprising the following steps:

[0043] S1. Establish an image database;

[0044] S2. Based on the image database obtained in step S1, establish a three-dimensional geometric model;

[0045] S3. Based on the three-dimensional geometric model in step S2, determine the orthopedic force loading area and determine the stress distribution on both sides of the concave and convex surfaces to be orthopedic through finite element analysis.

[0046] S4. Based on the stress distribution on both sides of the concave and convex surfaces to be corrected as determined in step S3, apply different degrees of corrective pressure to obtain the stress distribution of the three-dimensional geometric model under the action of corrective pressure, and establish a pressure value database.

[0047] S5. Compare the magnitude of the orthopedic force in the pressure zone monitored in real time by the force-sensing orthopedic pad with the data in the pressure value database. If the orthopedic force in the pressure zone exceeds the threshold range, adjust the shape and structure of the orthodontic body through the negative pressure control valve to adjust the orthopedic force until the orthopedic force monitored by the force-sensing orthopedic pad meets the pressure value database. If the orthopedic force in the pressure zone meets the threshold range, then orthodontic treatment is performed.

[0048] Compared with the prior art, the present invention has the following advantages:

[0049] 1. This invention utilizes variable stiffness to achieve changes in the structural stiffness of structured fabrics under negative pressure, satisfying the orthotic requirements of both flexible adaptation to body shape and rigid support for orthotics. Furthermore, the orthotic's internal variable stiffness structure adjusts the transition between rigidity and flexibility to adapt to the body shape and perform orthotics.

[0050] 2. The force-sensing corrective pad of the present invention can monitor the actual contact pressure during the orthodontic process, combine the data to assist in timely adjustment, and infer whether the position of the force-sensing corrective pad meets the orthodontic requirements by identifying the metal yarn or lead wire inside it.

[0051] 3. Compared with traditional orthotics, the main body of the orthodontic device of this invention can provide a larger orthodontic contact area. Combined with the external soft fiber material, it avoids discomfort during the orthodontic process and improves the accuracy of the orthodontic treatment.

[0052] 4. The variable stiffness structural material in this invention is lighter and has a better product appearance than traditional materials, which helps to improve compliance. Attached Figure Description

[0053] Figure 1 This is a first structural diagram of the variable stiffness orthosis device of the present invention;

[0054] Figure 2 This is a second structural diagram of the variable stiffness straightening device of the present invention;

[0055] Figure 3 This is a view of the inner surface of the pressure zone at point A in the variable stiffness straightening device of the present invention;

[0056] Figure 4 This is a structural diagram of the structured fabric in the variable stiffness orthopedic device of the present invention;

[0057] Figure 5 This is a diagram showing the variable stiffness of the structured fabric under negative pressure in the variable stiffness orthopedic device of the present invention.

[0058] Figure 6a This is a schematic diagram of the antagonistic rod structure in the variable stiffness orthopedic device of the present invention;

[0059] Figures 6b-6d These are three cross-sectional shapes of the antagonistic rod in the variable stiffness orthotic device of the present invention;

[0060] Figure 7a This is a cross-sectional structural diagram of the antagonistic rod after adding filler in the variable stiffness orthopedic device of the present invention;

[0061] Figure 7b This is a cross-sectional view of the antagonist bar in the variable stiffness straightening device of the present invention without the addition of filler material;

[0062] Figure 8 This is a flowchart of the variable stiffness method of the present invention;

[0063] Figure 9 This is a flowchart of the structured fabric manufacturing method of the present invention.

[0064] Key reference numerals:

[0065] The orthopedic body 1, structured fabric 11, discrete particle unit 111, enclosed space covering layer 112, pressure zone 12, release zone 13, negative pressure control valve 2, pressure sensing valve core 21, valve cover 22, force sensing corrective pad 3, tightening strap 4, strap connecting ring 41. Detailed Implementation

[0066] To fully describe the technical content, structural features, objectives, and effects of this invention, a detailed description will be provided below in conjunction with the accompanying drawings.

[0067] The method for manufacturing structured fabric 11 is as follows: Figure 9 As shown, the specific implementation steps are as follows:

[0068] S1. Select discrete particle element 111: Based on the requirements of contact and support stiffness at pressure zone 12, select a three-dimensional element structure that simultaneously satisfies the mass, contact and stiffness conditions from the three-dimensional element structures to be selected, and obtain discrete particle element 111 using modeling software.

[0069] In a preferred embodiment of the present invention, the process of establishing discrete particle unit 111 is as follows: first, in Blender software, open the Modify Geodesic Objects model modifier mesh input window through the Geodesic Dome plugin, create the selected three-dimensional unit structure using the Shape command, and adjust the circumscribed circle radius using the Radius setting command to determine the size of the discrete particle unit 111.

[0070] Furthermore, the discrete particle unit 111 includes hollow spheres, regular octahedrons, and regular hexahedrons; the cross-sectional shape of the antagonistic rod in the structured fabric 11 includes triangles, rhombuses, and ellipses. Different cross-sectional shapes can produce different contact effects of points, lines, and surfaces under negative pressure antagonism, thereby producing different structural stiffnesses.

[0071] Furthermore, in order to ensure that the size, structure and density of the discrete particle unit 111 meet the design requirements of 3D printing, it is necessary to ensure that the wall thickness of the key nodes of the discrete particle unit 111 is ≥0.6mm, the minimum hole diameter of the discrete particle unit 111 is ≥1mm, and the minimum wall thickness of the discrete particle unit 111 is ≥0.4mm.

[0072] Preferably, the three-dimensional unit structure meets the quality requirements of wearable devices, while a hollow structure is selected to reduce the overall weight.

[0073] Preferably, the contact condition satisfied by the three-dimensional unit structure is surface contact. Surface contact can prevent sharp ends from cutting through the negative pressure layer, while reducing local stress concentration and improving wearability comfort. The vertices of the three-dimensional unit structure should be chamfered or enclosed with planes and rounded corners. The expression for the normal stress is:

[0074] σ=F N / A≤[σ]

[0075] The expression for shear stress is:

[0076] τ=F s / A≤[τ]

[0077] Among them, F N F is the normal force acting on an object. s Let A be the shear force acting on the object, A be the cross-sectional area of ​​the object, [σ] be the allowable stress, and [τ] be the allowable shear stress.

[0078] Preferably, the stiffness condition satisfied by the three-dimensional unit structure is to avoid crushing failure of the unit structure during the application of negative pressure and the process of straightening.

[0079] S2. Establish structured fabric 11: Based on the parameters of discrete particle unit 111 obtained in step S1, connect discrete particle unit 111 into a base layer and a functional layer respectively, and connect the base layer and the functional layer to obtain a structured fabric 11 that meets the bending stiffness and tensile strength of flexible adaptive body.

[0080] Specifically, the base layer is formed by rotating adjacent discrete particle units 111 relative to each other by 30°, 45°, 60°, 90° or 120°. The rotation angle is determined according to the structural symmetry of the discrete particle units 111. All discrete particle units 111 are arranged in parallel and interlocked to form a strong chain-like structure layer. The functional layer is set between adjacent base layers. It is a structure layer obtained by rotating the discrete particle units 111 in the functional layer relative to the discrete particle units 111 in the base layer by 30°, 45°, 60°, 90° or 120°. The number of discrete particle units 111 in the functional layer is reduced to meet the construction of the spatial structured fabric 11.

[0081] S3. Test the performance of structured fabric 11:

[0082] S31. Based on the data of the model to be corrected, apply the modifier Array array, adjust the array number using the Count command, and adjust the array parameters using the Constant Offset command. The structured fabric 11 is obtained from the discrete particle unit 111, and pressure is applied to the boundary of the structured fabric 11. Antagonistic effects occur between the discrete particle units 111, and the structural interlocking changes from flexible to rigid. Perform three-point bending simulation on the structured fabric 11.

[0083] S32. Collect the length, width and height values ​​of the structured fabric 11 after deformation, and calculate the elastic bending modulus E of the structured fabric 11 to obtain the bending resistance performance of the orthodontic body 1.

[0084] S33. Simulate the interaction between discrete particle units 111 in the structured fabric 11 formed by discrete particle units 111 using the discrete element method. Calculate various stresses and deformation behaviors of the discrete particle units 111 in the structured fabric 11, study the elasticity, plasticity, and fracture behavior of the discrete particle units 111, and obtain the mechanical properties, durability, and deformation characteristics of the discrete particle units 111.

[0085] The structured fabric 11 is an assembly of discrete particle units 111. The calculation and solution are performed on each discrete particle unit 111 in the structured fabric 11. It is assumed that the force between the discrete particle units 111 is proportional to the relative displacement between them. The motion equation of each discrete particle unit 111 is established using Newton's second law.

[0086] The contact stiffness is determined based on the stress wave propagation conditions in the discrete particle element 111, that is, within one calculation time step, the stress wave experienced by each discrete particle element 111 can only be transmitted to the element connected to it.

[0087] Let the masses of adjacent discrete particle units 111 be m1 and m2, respectively, and their horizontal displacements during the contact process be x1 and x2, respectively. Then the required normal stiffness is k. n The equation of motion is:

[0088]

[0089]

[0090] Let the amplitudes of adjacent discrete particle units 111 be A1 and A2, respectively, ω i Let be the angular frequency of the i-th mode, and the displacement equation be:

[0091] x1=A1cosω i t

[0092] x2=A2cosω i t

[0093] Substituting the displacement equation into the motion equation, we obtain the eigenvalue matrix of the equation as follows:

[0094]

[0095] The maximum natural frequency is obtained as follows:

[0096] f max =((m1+m2)k n / (m1m2)) 1 / 2 / (2π)

[0097] Based on the fact that the maximum permissible wavelength of the stress wave in a discrete particle unit 111 is twice the side length of the discrete particle unit 111, let l min Let c be the side length of the smallest block in the vibration system. p Let be the propagation velocity of the longitudinal disturbance in the discrete particle element 111, then:

[0098] f max =c p / (2l min )

[0099] Combining the elastic modulus E, Poisson's ratio v, and density ρ of the discrete particle unit 111, then:

[0100] c ρ =(E(1-v) / (ρ(1+v)(1-2v))) 1 / 2

[0101] In summary, the expression for the normal stiffness of discrete particle element 111 is:

[0102]

[0103] Where m1 and m2 are the masses of two adjacent particle units, E is the elastic modulus, v is Poisson's ratio, ρ is density, and l min The side length of the particle unit;

[0104] The tangential stiffness k of the discrete particle element 111 is determined based on the maximum propagation frequency of the stress shear wave in the discrete particle element 111. τ The expression is:

[0105]

[0106] Where m1 and m2 are the masses of two adjacent particle units, G is the shear modulus, ρ is the density, and l min The side length of the particle unit;

[0107] The expression for the contact pressure P between discrete particle units 111 is:

[0108] P = kx

[0109] Where k is the contact stiffness and x is the displacement during the contact process;

[0110] Finally, the structured fabric 11 is analyzed based on the contact between discrete particle units 111.

[0111] S34. Compare the bending modulus E and contact pressure P obtained in steps S32 and S33 with the initial support force and orthotics force of the orthodontic device, and determine whether the performance of the structured fabric 11 meets the requirements by combining the strength data of the spinal orthodontic device and the data in the orthotics force database.

[0112] S4. Based on the topology layout optimization theory that integrates size, shape, and topology, the size, shape, and topology of the discrete particle unit 111 are combined and optimized to obtain a discrete particle unit 111 with advantages such as economy and practicality: the border of the discrete particle unit 111 is extracted, and according to the performance test results obtained in step S3, the wireframe modifier is applied to optimize the size, shape, and topology of the discrete particle unit 111. The thickness modifier is used to adjust the size, structure, and density of the discrete particle unit 111, the thickness and width of the antagonistic rod are adjusted, the surface of the discrete particle unit 111 is subdivided using the subdivision surface modifier, the level of subdivision is adjusted using the Levels Viewport window, and the detail of the smooth surface of the discrete particle unit 111 is adjusted. Thus, through topology control, the sliding characteristics between discrete particle units 111 are enhanced, the contact between discrete particle units 111 is enhanced, the density of the structured fabric 11 is reduced, and the conformal flexibility is increased while improving the structural stiffness of the structure after negative pressure.

[0113] The expression for the optimization model is:

[0114]

[0115] Where W is the total mass of discrete particle unit 111, t is the topology design variable of discrete particle unit 111, t=(t1,t2,…,t n ) T , ρ i Let l be the density of the i-th group of antagonistic rods. j Let G be the length of the j-th antagonistic rod, j∈G i A i Let i be the cross-sectional design variable for the i-th discrete particle element 111, where i = 1, 2, ..., n. Let S1 be the upper limit of the cross-sectional design variables, P be the number of elements in it, and assume that S1 < S2 < ... < S PC is the shape design variable, usually taken as the node coordinates, C = (C1, C2, ..., C f ) T , i = 1, 2, ..., n, j ∈ G i G i Let σ be the set of antagonistic rod numbers belonging to the i-th group. i , u k , These are the upper and lower limits of stress and displacement, respectively, σ jl Let u be the stress of the j-th antagonistic bar under the l-th working condition, where l = 1, 2, ..., 0. kl Let S be the k-th constrained displacement value under the l-th working condition, where k = 1, 2, ..., R, and S is the discrete set of the cross-sections of the discrete particle element 111. Let be the upper limit of shape variables, D be the discrete set of shape variables, H be the number of shape variables, n be the number of bar groups, O be the number of working cases, and R be the number of displacement constraints.

[0116] Specifically, the parameters optimized in this optimization process include the size, structure, and density of discrete particle units, the level of detail of the smooth surface of the discrete particle units, and the thickness and width of the antagonistic bars.

[0117] In a specific embodiment of the present invention, the sliding characteristic refers to the movable space between discrete particle units 111. The larger the space, the higher the flexibility of the structured fabric 11. The contact and sliding characteristics between discrete particle units 111 are opposite. The larger the contact surface or line, the smaller the movable range of the discrete particle unit 111, but the better the variable stiffness effect.

[0118] S5. Fabrication of structured fabric 11: Using relevant processes, based on the structure, density and mechanical performance parameters of the discrete particle unit 111 optimized in step S4, a material that meets the performance parameters obtained in step S3 is selected to print the structured fabric 11. After processing and encapsulation, the printed structured fabric 11 becomes the orthopedic body 1.

[0119] Furthermore, materials that meet the performance parameters obtained in step S3 include nylon plastics, TPU materials, and alloy materials.

[0120] Variable stiffness orthotic devices, such as Figures 1-9 As shown, it includes the orthotic body 1, negative pressure control valve 2, force-sensing corrective pad 3, and tightening strap 4.

[0121] The outer surface of the orthotic body 1 is made of soft fiber fabric, which makes the contact surface with the user more flexible and adaptable to the user's body shape.

[0122] The force-sensing orthopedic pad 3 is made of rough paper, cotton, or sponge, and has metal yarn or lead wire inside. It is connected to the orthodontic body 1 by magnetic or Velcro to strengthen the fixation of the orthodontic force position and correct residual angularity and lateral displacement. The tightening strap 4 is made of leather or fiber fabric to provide a better appearance.

[0123] The force-sensing orthotic pad 3 has a deformable thin film pressure sensor on its surface, which monitors the orthotic force applied to the body when the user wears the orthotic and whether the orthotic force is normal, providing a reference for evaluating the orthotic effect and determining whether the orthotic needs to be adjusted.

[0124] The first and second mounting ends of the orthotic body 1 are connected to the negative pressure control valve 2 and the tightening strap 4, respectively. The bottom of the negative pressure control valve 2 is connected to the first mounting end of the orthotic body 1 by adhesive bonding. The orthotic body 1 has a structured fabric 11 inside. Through the orderly arrangement and multi-layer superposition of discrete particle units 111 in a three-dimensional spatial structure, an interlocking fabric structure is formed from point to line, from line to surface, and from surface to body. The structure is wrapped with a polymer material to form a closed space covering layer 112. This allows the orthotic body to switch between a flexible adaptive shape and a rigid support state according to changes in internal air pressure within a closed space. The closed space covering layer 112 can be made of a variable stiffness material with adjustable stiffness or a material with certain adaptability. The discrete particle unit 111 forms a certain surface contact support with the inner surface of the enclosed space. The antagonistic rod of the discrete particle unit 111, which plays an antagonistic role, can be equipped with a reinforcing material or a honeycomb pore structure to ensure that the structural strength of the discrete particle unit 111 meets the compression strength requirements. At the same time, it adjusts the overall quality of the structured fabric 11 and improves the correctness of wearing the orthosis.

[0125] The orthotic body 1 is divided into a pressure zone 12 and a through-type pressure release zone 13 according to the orthotic requirements. Discrete particle units 111 within the pressure zone 12 and release zone 13 are set with the same or different sizes, structures, and densities to apply orthotic force and release pressure. Larger discrete particle units 111 result in lower density of the structured fabric 11, poorer adaptability, lower fit, higher porosity, and less structural stiffness to meet support requirements. Conversely, smaller discrete particle units 111 result in higher density of the structured fabric 11, better adaptability, higher fit, lower porosity, and easier structural stiffness to meet support requirements. Simultaneously, differences in the internal structure and material density of the discrete particle units 111 also lead to differences in mechanical properties, thus affecting the conformal and support capabilities of the structured fabric 11. Force-sensing corrective pads 3 are provided on the inner surface of the pressure zone 12 of the orthotic body 1.

[0126] The discrete particle units 111 in the structured fabric 11 and the inner surface contact area of ​​the enclosed space covering layer 112 form a certain surface contact support, thereby ensuring a good fit and support with the human body surface, improving orthopedic stability, ensuring the contact area between the orthodontic body 1 and the user, and making the contact pressure distribution on the contact surface uniform, thus improving user compliance.

[0127] The negative pressure control valve 2 can control the internal air pressure according to the pressure required by the closed space inside the orthotic body 1, so that the structured fabric 11 can achieve bidirectional stiffness conversion between flexibility and rigidity through antagonistic effect. It includes a pressure sensing valve core 21 and a valve cover 22. The connecting end of the pressure sensing valve core 21 is connected to the fixed end of the valve cover 22. The pressure sensing valve core 21 is connected to the closed space inside the orthotic body 1. The tightening straps 4 are vertically distributed on the side of the outer surface of the orthotic body 1. The front of the tightening straps 4 is fixedly provided with a strap connecting ring 41 that cooperates with the tightening straps 4. The tightening straps 4 are fixed by Velcro or buckle, thereby binding the orthotic and strengthening its fixation on the human body.

[0128] Specifically, the pressure sensing valve core 21 includes a pressure sensing module, a spring, and a sealing diaphragm. The pressure sensing module senses the change in pressure signal within the enclosed space covering layer 112 and then controls the spring and sealing diaphragm to cut off or connect the negative pressure vacuum system, control the airflow direction, and adjust the internal air pressure so that the structural stiffness of the structured fabric 11 changes accordingly, completing the bidirectional conversion of the orthosis between flexibility and rigidity; the force sensing correction pad 3 is equipped with a deformable thin film pressure sensor inside.

[0129] The structured fabric 11 includes discrete particle units 111 and a closed space covering layer 112. The discrete particle units 111 are located inside the closed space covering layer 112, and two adjacent discrete particle units 111 are connected by antagonistic rods.

[0130] Figures 6a-7b Z represents the cross-section of the rod structure; Figures 6b-6d These are three cross-sectional shapes for rod structures.

[0131] Figure 7a The diagram shows the cross-sectional structure of the antagonistic bar after the addition of filler material in the improved design. Figure 7a Z1 is the reinforcement point of the antagonistic rod; Figure 7b This is a structural diagram of the cross-section of the antagonistic bar without added filler. Figure 7b Z2 is the pore point of the antagonistic rod.

[0132] Variable stiffness methods, such as Figure 8 As shown, it includes the following steps:

[0133] S1. Collect the biplane orthogonal X-ray film and grating scan data to be corrected, and establish an image database.

[0134] S2. Based on the image database obtained in step S1, establish a three-dimensional geometric model of the cervical, thoracic, lumbar and sacral region.

[0135] S3. Based on the three-dimensional geometric model in step S2, determine the orthopedic force loading area, and determine the stress distribution on both sides of the concave and convex surfaces to be orthopedic through finite element analysis.

[0136] The specific steps of finite element analysis are as follows:

[0137] 1. Mesh generation: Discretize the three-dimensional geometric model of the cervical, thoracic, lumbar and sacral regions into a finite element mesh.

[0138] 2. Assign material properties: Define material properties, including elastic modulus, Poisson's ratio, and density.

[0139] 3. Load application: Determine the force conditions of the three-dimensional geometric model of the cervical, thoracic, lumbar and sacral region, including the forces, pressures, constraints and boundary conditions applied to the three-dimensional geometric model of the cervical, thoracic and lumbar and sacral region.

[0140] 4. Run the simulation and perform data analysis.

[0141] S4. Based on the stress distribution on both sides of the concave and convex surfaces to be corrected as determined in step S3, apply different degrees of corrective pressure to obtain the stress distribution of the three-dimensional geometric model under the action of corrective pressure. Use the pressure value when the asymmetric stress is zero as the reference value of the corrective pressure to establish a database of pressure values ​​when the asymmetric stress is zero.

[0142] S5. Compare the magnitude of the orthopedic force of the pressure zone 12 monitored in real time by the force-sensing orthopedic pad 3 with the data in the pressure value database. If the orthopedic force of the pressure zone 12 exceeds the threshold range, then, based on the rigid-flexible coupling characteristics of the structured fabric 11 and the finite element analysis data, adjust the shape structure of the orthodontic body 1 through the negative pressure control valve 2 to adjust the orthopedic force until the orthopedic force monitored by the force-sensing orthopedic pad 3 meets the pressure value database. If the orthopedic force of the pressure zone 12 meets the threshold range, then orthopedic treatment is performed.

[0143] The following describes in further detail a structured fabric manufacturing method, a variable stiffness straightening device, and a variable stiffness method of the present invention, with reference to embodiments:

[0144] The working principle of the variable stiffness scoliosis correction device of the present invention is as follows:

[0145] When using this variable stiffness scoliosis orthosis, the orthosis body 1, customized according to the body model of the user to be corrected, and the user are flexibly adapted, and the shape of the orthosis is determined by comprehensively considering the correction needs.

[0146] Open the valve cover 22 of the negative pressure control valve 2 to perform a negative pressure vacuum process on the pressure sensing valve core 21. At this time, the sealing diaphragm inside the pressure sensing valve core 21 opens, and gas flows out from the orthodontic body 1. Through the closed space covering layer 112, the structure of the flexible structured fabric 11, which is composed of three-dimensional discrete particle units 111, is transformed into a rigid support structure with support capabilities.

[0147] Place the force-sensing corrective pad 3 in the pressure zone 12 defined on the orthotic body 1, which is in contact with the user, and put the orthotic on the user's body. Secure the orthotic to the user's body by tightening the strap connecting ring 41 on the strap 4, thus completing the wearing process.

[0148] The magnitude of the orthodontic force is measured in real time by the force-sensing orthodontic pad 3 to determine whether the orthodontic force is normal and to complete the fitting. At the same time, regular checks on scoliosis and measurements of orthodontic force are performed to understand whether the deformity has improved and whether the orthodontic force provided by the orthodontic device is normal, providing a reference for evaluating the orthodontic effect and determining whether the orthodontic device needs to be adjusted.

[0149] Meanwhile, during use, the data of the pressure sensing valve core 21 is monitored and adjusted in a timely manner to ensure the pressure inside the enclosed space covering layer 112 is stable. When the shape and orthotic force of the orthosis do not meet the orthotic requirements, the valve cover 22 of the negative pressure control valve 2 needs to be opened to allow gas to flow into the interior of the orthotic body 1 through the pressure sensing valve core 21, restore the softness of the structured fabric 11, and repeat the operation during wearing to complete the adjustment of the orthotic structure shape.

[0150] During use, check whether the position of the force-sensing correction pad 3 is correct. If it is not correct, adjust it in time to ensure that the force application position does not slip. This variable stiffness correction device has better correction effect, better adaptability and compliance, and is more economical and practical.

[0151] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for manufacturing a structured fabric for orthopedic devices, characterized in that, It includes the following steps: S1. Select discrete particle elements: Based on the requirements of contact and support stiffness in the pressure zone, select a three-dimensional element structure that simultaneously satisfies the mass, contact and stiffness conditions from the three-dimensional element structures to be selected, and obtain discrete particle elements using modeling software. S2. Establishing a structured fabric: Based on the parameters of the discrete particle units obtained in step S1, the discrete particle units are connected into a base layer and a functional layer, and the base layer and the functional layer are connected to obtain a structured fabric that meets the bending stiffness and tensile strength of the flexible body. S3. Test the properties of structured fabrics: S31. Based on the data of the model to be corrected, adjust the shape of the structured fabric and apply pressure to the boundary of the structured fabric to perform multi-point bending simulation of the structured fabric. S32. Collect the length, width and height values ​​of the structured fabric after deformation, and calculate the elastic bending modulus E of the structured fabric to obtain the bending resistance of the orthodontic body. S33. Determine the contact pressure P between discrete particle units in a structured fabric: The expression for the normal stiffness of the discrete particle unit is: ； Where m1 and m2 are the masses of two adjacent particle units, E is the elastic modulus, v is Poisson's ratio, ρ is density, and l min The side length of the particle unit; The expression for the tangential stiffness of the discrete particle unit is: ； Where m1 and m2 are the masses of two adjacent particle units, G is the shear modulus, ρ is the density, and l min The side length of the particle unit; The expression for the contact pressure P between discrete particle units is: ； Where k is the contact stiffness and x is the displacement during the contact process; S34. Compare the bending modulus E and contact pressure P obtained in steps S32 and S33 with the initial support force and orthotics force of the orthotine, and determine whether the performance of the structured fabric meets the requirements by combining the orthotics strength data and the data in the orthotics force database. S4. Optimize discrete particle units: Extract the outline of discrete particle units, and optimize the size, shape and topology of discrete particle units based on the performance test results obtained in step S3, thereby enhancing the sliding characteristics between discrete particle units, enhancing the contact between discrete particle units, reducing the density of structured fabric, and increasing conformal flexibility while improving the stiffness of structured fabric after negative pressure. The expression for the optimization model is: ； Where W is the total mass of the discrete particle element, t is the topology design variable of the discrete particle element, and t = (t1, t2, ..., t3). n ) T , Let the density of the i-th group of antagonistic rods be denoted as . Let j be the length of the antagonistic rod. Let be the cross-sectional design variable for the i-th discrete particle element, i = 1,2,...,n. Let P be the upper limit of the cross-sectional design variables, P be the number of elements, and C be the shape design variables, where C = (C1, C2, ..., C...). f ) T , i = 1,2,...,n,j∈G i , Let i be the set of antagonistic rod numbers belonging to the i-th group. , , , These are the upper and lower limits of stress and displacement, respectively. Let be the stress of the j-th antagonistic bar under the l-th working condition, where l = 1,2,...,0. Let S be the k-th constrained displacement value under the l-th working condition, where k = 1,2,...,R, and S is the discrete set of the cross-sections of the discrete particle element. Here, denoted as the upper limit of shape variables, D as the discrete set of shape variables, H as the number of shape variables, n as the number of bar groups, O as the number of working cases, and R as the number of displacement constraints. S5. Fabrication of structured fabric: Based on the structure, density, and mechanical property parameters of the discrete particle unit optimized in step S4, select materials that meet the performance parameters in step S3 to print the structured fabric.

2. The method for manufacturing structured fabric for orthopedic devices according to claim 1, characterized in that, In step S1, the printing parameters of the three-dimensional unit structure include key node wall thickness ≥ 0.6 mm, minimum hole diameter ≥ 1 mm, and minimum wall thickness ≥ 0.4 mm.

3. The method for manufacturing structured fabric for orthopedic devices according to claim 1, characterized in that, In step S1, the contact condition is surface contact, and the expression for the normal stress is: ； The expression for shear stress is: ； Among them, F N F is the normal force acting on the object. s Let A be the shear force acting on the object, and let A be the cross-sectional area of ​​the object subjected to the force. For allowable stress, Allowable shear stress.

4. The method for manufacturing structured fabric for orthopedic devices according to claim 1, characterized in that, In step S2, the base layer is a robust chain-like structure layer formed by rotating adjacent discrete particle units relative to each other by a certain angle and arranging all discrete particle units in parallel and interlocking. The functional layer is a structure layer formed by setting functional layers between adjacent base layers and rotating the discrete particle units located in the functional layer relative to the discrete particle units located in the base layer by a certain angle.

5. The method for manufacturing structured fabric for orthopedic devices according to claim 1, characterized in that, In step S4, the optimized parameters include the size, structure, and density of the discrete particle units, the level of detail of the smooth surface of the discrete particle units, and the thickness and width of the antagonistic bars.

6. The method for manufacturing structured fabric for orthopedic devices according to claim 1, characterized in that, In step S5, the materials include nylon plastic, TPU material, and alloy material.

7. A variable stiffness orthotic device prepared using the structured fabric manufacturing method for orthotic devices according to any one of claims 1-6, characterized in that, It includes the orthotic body, a negative pressure control valve, a force-sensing corrective pad, and the structured fabric. The first and second mounting ends of the orthotic body are respectively connected to the negative pressure control valve, the force-sensing corrective pad, and the tightening strap. The orthotic body is provided with structured fabric inside. The orthotic body is divided into a pressure zone and a release zone according to the orthotic requirements. The inner surface of the pressure zone of the orthotic body is provided with a force-sensing corrective pad. The negative pressure control valve includes a pressure-sensing valve core and a valve cover. The connecting end of the pressure-sensing valve core is connected to the fixed end of the valve cover. The structured fabric includes discrete particle units and a closed-space covering layer. The discrete particle units are located inside the closed-space covering layer, and adjacent discrete particle units are connected by antagonistic rods.

8. The variable stiffness orthotic device according to claim 7, characterized in that, The discrete particle unit includes hollow spheres, regular octahedrons, and regular hexahedrons; the cross-sectional shape of the antagonistic rods in the structured fabric includes triangles, rhombuses, and ellipses.

9. The variable stiffness orthotic device according to claim 8, characterized in that, The pressure-sensing valve core includes a pressure-sensing module, a spring, and a sealing diaphragm; the force-sensing correction pad has a deformable thin-film pressure sensor inside.

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