Individualized ear mold integrated manufacturing method based on multi-material digital light processing

Abstract

The embodiment of the application discloses a personalized ear mold integrated manufacturing method based on multi-material digital light processing, and relates to the technical field of additive manufacturing. The method comprises the following steps: obtaining a three-dimensional numerical model of a personalized ear mold of a specific patient; adding a static load based on the self-weight of a hearing aid and a dynamic load based on the periodic force of chewing movement to the numerical model, and performing dynamic stress analysis on the numerical model based on the added load; dividing material regions with different hardnesses in the numerical model based on the stress analysis result, including a rigid support region, a flexible sealing region and a transition region; determining the volume fraction of rigid materials and flexible materials for DLP three-dimensional printing at each position in the transition region according to a stress gradient line; and determining the printing energy density at each position in the transition region according to the volume fraction and the printing energy density of the rigid support region and the flexible sealing region. The embodiment can improve the quality and efficiency of ear mold manufacturing.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the field of additive manufacturing technology, and particularly relates to an individualized ear mold integrated manufacturing method based on multi-material digital light processing. BACKGROUND

[0002] As the core carrier of hearing aids, hearing protection devices and in-ear devices, the manufacturing technology of ear molds has long been faced with the following difficulties:

[0003] 1) Defects of manual molding: The existing molding process relies on manual molding (silicone mold material injection into the ear canal), which is prone to deformation or bubble residue due to the complex shape of the patient's ear canal (such as a bending degree of > 90°). According to statistics, clinical data shows that about 15%-20% of ear molds need to be reworked; other methods such as plaster casting take 3-7 days to complete, which cannot meet the immediate needs of patients with acute hearing loss.

[0004] 2) Precision and adaptability problems: The surface roughness of manually produced ear molds (> 50 μm, microns) is prone to cause pressure sores or poor sealing (leakage rate > 10 dB, decibels) in the ear canal, affecting the acoustic performance of the hearing aid; single material (such as medical silicone) cannot meet the mechanical requirements of different areas of the ear mold (such as rigid support for the concha cavity and flexible sealing for the ear canal section), resulting in poor long-term wear comfort.

[0005] In recent years, although DLP (Digital Light Processing) technology has been introduced into ear mold manufacturing, there are still significant technical bottlenecks:

[0006] 1) Limitations of single-material printing: Existing DLP ear molds generally use a single photosensitive resin (such as acrylonitrile-butadiene-styrene copolymer resin), which has a fixed elastic modulus (usually 2-3 GPa), which cannot meet the needs of functional zoning of the ear mold for gradual changes in material rigidity and flexibility (such as an elastic modulus of 0.5-2 MPa (megapascal) for the ear canal sealing area);

[0007] 2) Insufficient precision in dividing multi-material rigid and flexible areas: It is mostly based on human experience to uniformly divide different material areas (such as roughly dividing into concha cavity area, ear canal area, etc.), which is difficult to adapt to the individualized situation of patients for wear comfort, and bending and cracking are prone to occur between areas;

[0008] 3) Technical obstacles of multi-material printing: Insufficient material switching precision. Traditional multi-material DLP uses a mechanical nozzle to switch, with a switching interval error of > 100 μm, which causes material misalignment between layers and affects the sealing of the ear mold; low interface bonding strength: the bonding strength between layers of heterogeneous materials is insufficient (< 5 MPa), which is prone to delamination and cracking at the bending part of the ear mold;

[0009] 4) Low post-processing efficiency: the support structure needs to be removed manually, which may damage the fine structure of the ear mold (such as air holes and acoustic channels); the traditional isopropanol cleaning + UV secondary curing post-processing procedure takes more than 2 hours, and residual uncured monomers (residual rate > 0.5%) may cause biological safety problems.

[0010] Based on the above difficulties or bottlenecks, the entire ear mold manufacturing field has the following pain points:

[0011] 1) Unable to adapt to the trend of personalized medicine: under the trend of increasing demand for customized ear molds, existing technologies are difficult to achieve "structure-material-function" integrated customization;

[0012] 2) Upgrade patient experience: clinical research shows that 62% of users reduce the wearing time due to discomfort (hardness is not suitable, poor air permeability) of the ear mold;

[0013] 3) Production cost pressure: the traditional ear mold rework rate is as high as 20%, which increases the cost of single piece and restricts large-scale popularization. SUMMARY

[0014] Embodiments of the present application provide an individualized ear mold integrated manufacturing method based on multi-material digital light processing to solve at least one of the above problems.

[0015] In a first aspect, embodiments of the present application provide an individualized ear mold integrated manufacturing method based on multi-material digital light processing, comprising:

[0016] Obtaining a three-dimensional numerical model of an individualized ear mold for a specific patient;

[0017] Adding a static load based on the weight of a hearing aid and a dynamic load based on the periodic force of chewing motion to the numerical model, and performing dynamic stress analysis on the numerical model based on the added load;

[0018] Based on the stress analysis result, dividing the numerical model into material regions of different hardness, including a rigid support region, a flexible sealing region, and a transition region;

[0019] According to the stress gradient line, determining the volume fraction of rigid material and flexible material for DLP three-dimensional printing at each position in the transition region;

[0020] According to the volume fraction, and the printing energy density of the rigid support region and the flexible sealing region, determining the printing energy density at each position in the transition region.

[0021] In a second aspect, embodiments of the present application provide an electronic device, comprising:

[0022] One or more processors;

[0023] a memory storing one or more programs,

[0024] When the one or more programs are executed by the one or more processors, the one or more processors implement the method for manufacturing personalized earmold based on multi-material digital light processing according to any one of the embodiments.

[0025] In a third aspect, the embodiments of the present application further provide a computer readable storage medium, which stores a computer program, and the program is executed by a processor to implement the method for manufacturing personalized earmold based on multi-material digital light processing according to any one of the embodiments.

[0026] To sum up, the embodiments of the present application provide a method for manufacturing personalized earmold based on multi-material digital light processing. First, the dynamic stress analysis is performed on the earmold numerical model according to the actual wearing condition of the hearing aid, and different material regions (including rigid support region, flexible sealing region and material transition region) are automatically divided according to the stress analysis results, so as to improve the matching accuracy of the region division and the actual stress condition of the hearing aid. Then, the material ratio of the material transition region is optimized by using the stress gradient line, so as to better fit the irregular shape of the hearing aid and realize the fine transition of the material and hardness. Finally, based on the printing material distribution, the multi-material DLP printing method and the dynamic mask technology are used to control the light curing wavelength of different regions, so as to realize the material forming with sub-millimeter level precision, and truly realize the seamless material gradient within the same printing layer and the material gradient between the printing layers. The method of the embodiments is suitable for custom hearing aids, including earmold and custom shell, etc. The earmold manufacturing period can be shortened to 4 hours, the tensile strength is improved by 30%-50%, the elastic modulus of the sealing region can be adjusted in the range of 0.5-5MPa, and the surface roughness Ra is less than 10μm. The period and quality of the personalized earmold customization are greatly improved, and the patient experience is improved. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0028] Figure 1 is a flowchart of a method for manufacturing personalized earmold based on multi-material digital light processing provided by the embodiments of the present application;

[0029] Figure 2 is a schematic diagram of a simplified STL model of an earmold provided by the embodiments of the present application;

[0030] Figure 3 is a corresponding area division schematic diagram of the ear mold; Figure 2 is a corresponding numerical modeling calculation grid division schematic diagram;

[0031] Figure 4 is a corresponding area division schematic diagram of the ear mold; Figure 3

[0032] Figure 5 is a corresponding area division schematic diagram of another ear mold provided by the embodiment of the present application;

[0033] Figure 6 is a corresponding microstructure schematic diagram of the material transition in the layer; Figure 4

[0034] Figure 7 is a corresponding microstructure schematic diagram of the material transition between layers; Figure 5

[0035] Figure 8 is a structure schematic diagram of an electronic device provided by the embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0037] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. ​​​

[0039] Figure 1 is a flowchart of an individualized earmold integrated manufacturing method based on multi-material digital light processing provided by an embodiment of the present application. The method is applicable to the case of manufacturing a hearing aid earmold using DLP 3D (three-dimensional) printing technology, and is executed by an electronic device. As shown in Figure 1 , the method specifically includes:

[0040] S110, obtaining a three-dimensional numerical model of an individualized earmold of a specific patient.

[0041] Generally, the earmold morphologies of different patients are also different. The embodiment is directed to different patients, and the numerical model of the patient's own earmold is obtained, thereby providing a basis for individualized customization of the earmold.

[0042] In a specific embodiment, a three-dimensional geometric model of the earmold can be established first. Optionally, the existing ear shape model of the patient is scanned by a structured light camera or other scanning sensor to collect point cloud data, and the point cloud is generated by collection to generate an STL (StereoLithography) file.

[0043] Then, the STL file is repaired. Optionally, the Marching Cubes algorithm is used to fill the holes in the scanning data; and then the surface noise is eliminated (for example, the surface roughness Ra<5μm) by Laplace smoothing (for example, iteration 3 times, smoothing factor 0.6).

[0044] Next, the smoothed geometric model is preprocessed. For the imported three-dimensional scanning model of the patient's ear (STL format, accuracy less than 0.05mm), local defect points are removed, and overall fitting is performed to adapt to subsequent numerical modeling.

[0045] Finally, the three-dimensional model is discretized into a finite element grid (tetrahedral element, edge length less than 0.5mm); for the details of different patient's earmolds, fine mesh can be added locally to improve the expression of the geometric shape. Figure 2 and Figure 3 Taking a simplified customized shell as an example, the differences between the STL model and the mesh division model are shown respectively.

[0046] S120, adding a static load based on the self-weight of the hearing aid and a dynamic load based on the periodic force of the chewing motion to the numerical model, and performing dynamic stress analysis on the numerical model based on the added load.

[0047] This step constructs an adaptive dynamic stress model according to the stress characteristics of the hearing aid in actual wearing, to simulate the real stress state of the hearing aid. In a specific embodiment, the construction process can include the following steps:

[0048] Step one, set the biomechanical parameters acting on the ear mold, including the elastic modulus of the ear canal skin and the maximum bite force of the chewing movement. Among them, the ear canal skin is in contact with the outer surface of the ear mold, which will affect the stress and deformation of the ear mold; and the chewing movement as an external force will also affect the stress state of the ear mold. Therefore, this embodiment specially sets these biomechanical parameters to provide a basis for subsequent mechanical analysis. For example, the elastic modulus of the ear canal skin can be 0.1-0.5MPa, and the maximum bite force of the chewing movement can be 50 to 150N (Newton), which can be flexibly selected according to the patient's condition in actual application.

[0049] Step two, set the material model of the ear mold as a linear elastic model, which follows the generalized Hooke's law. This step sets the material properties of the ear mold, and the mechanical analysis of the ear mold conforms to the generalized Hooke's law: wherein, σ ij represents the stress tensor, C ijkl represents the material stiffness tensor, represents the strain tensor.

[0050] Step three, according to the actual wearing situation, set the interface fixed constraint on the contact part of the numerical model and the hearing aid. This step sets the initial conditions of the model as a free body, and then sets the boundary conditions. Optionally, according to the actual wearing situation, set the interface fixed constraint on the contact part of the ear mold and the hearing aid (such as the hearing aid circuit board, etc.), which restricts the displacement freedom degree of the ear mold and the hearing aid buckle connection along the X / Y / Z direction.

[0051] Step four, uniformly apply the self-weight of the hearing aid as a static load on the contact part of the numerical model and the concha cavity; periodically apply the maximum bite force of the chewing movement as a dynamic load on the outer surface of the numerical model. This step adds a load on the contact part of the ear mold and the ear canal, wherein the static load includes the self-weight of the hearing aid, which is uniformly distributed on the contact surface of the concha cavity (i.e. the outer shell of the ear mold); the dynamic load includes the periodic force of the chewing movement, which is applied to the bite force acting area of the outer surface of the ear mold. For example, the self-weight of the hearing aid can be 10g (grams), i.e. 0.098N of self-weight force; the periodic force of the chewing movement can be ±20N in amplitude and 1Hz in frequency. Similarly, the specific values can be adjusted according to the actual situation of the hearing aid and the patient.

[0052] Step five, based on the elastic modulus, interface fixed constraint and load, perform dynamic stress analysis of the numerical model under the generalized Hooke's law. After the settings of steps one to four, run the dynamic stress analysis function, which can automatically run the dynamic stress change of the numerical model under the generalized Hooke's law.

[0053] S130, based on the stress analysis result, dividing the material regions of different hardness in the numerical model, including rigid support region, flexible sealing region and transition region.

[0054] This step automatically divides the patient's ear mold numerical model into different regions according to the stress solving result, and each region will correspond to different material hardness. Specifically, these regions include rigid support region (referred to as rigid region), flexible sealing region (referred to as flexible region), and transition region between rigid support region and flexible sealing region. Figure 4 and Figure 5 The region division results of the two customized shells are shown respectively. Among them, Figure 5 In addition to the above-mentioned several regions, the air permeable region is also included, and the division method of the air permeable region in this embodiment is not limited, Figure 5 Only as a division example of the above-mentioned rigid region and flexible region.

[0055] In a specific embodiment, the von Mises stress σ vonMises The continuous region with von Mises stress σ ≥ 5 MPa or contact pressure p ≥ 0.3 MPa is divided into rigid support region using rigid material; the continuous region with 0.1 MPa ≤ p < 0.3 MPa and contact area ≥ 50% is divided into flexible sealing region using flexible material. Among them, each parameter in the above judgment condition is dynamically changed under the action of dynamic load, such as the deformation of ear canal during chewing, the dynamic change of contact area with the surface of hearing aid, therefore the value of each parameter in the above judgment condition can take the average value in dynamic stress analysis.

[0056] S140, according to the stress gradient line, determining the volume fraction of rigid material and flexible material for DLP three-dimensional printing at each position in the transition region.

[0057] In this embodiment, in DLP 3D printing, rigid material with larger hardness is configured for rigid support region, flexible material with smaller hardness is configured for flexible sealing region, and in transition region, the volume fraction of rigid material and flexible material used at each position is adjusted according to the stress gradient line, so as to obtain the material with gradually changing hardness. Optionally, the rigid material can be selected from glass fiber reinforced resin, and the flexible material can be selected from organic silicon modified polyurethane acrylate.

[0058] In a specific embodiment, the stress gradient line in the transition region can be determined by the following way:

[0059] Step one, taking any position in the transition region as the starting point, respectively extending the stress gradient line along the gradient direction of stress rising and / or stress falling, until the stress gradient line intersects with a rigid support region and / or a flexible sealing region.

[0060] Specifically, according to the region division obtained from the stress analysis result, the rigid support region and the flexible sealing region can each have multiple. Optionally, each grid adjacent to any flexible sealing region in the transition region can be taken as a starting point, and multiple stress gradient lines can be extended respectively. Taking one adjacent grid as an example, the next grid is determined along the gradient direction of stress rise with the grid as a starting point; the next next grid is determined along the gradient direction of stress rise with the next grid as a starting point; and the extension is gradually extended until the final grid is adjacent to a rigid support region (i.e. reaching the rigid support region). At this time, the grids determined step by step are connected in turn according to the order of monotonically increasing stress, and a stress gradient line can be obtained. The above operation is performed for each grid in the transition region adjacent to the flexible sealing region, and multiple stress gradient lines can be obtained.

[0061] Similarly, each grid adjacent to any rigid support region in the transition region can also be taken as a starting point, and multiple stress gradient lines can be extended respectively. The difference is that each step of extension is to determine the next grid along the gradient direction of stress drop.

[0062] Step two, according to the length of the stress gradient line after intersection and the position of the arbitrary position in the stress gradient line after intersection, the volume fraction of rigid material and flexible material for DLP three-dimensional printing at the arbitrary position is determined.

[0063] In the transition region, the volume fraction of rigid material is controlled to gradually decrease from 100% to 0% in the direction from the rigid support region to the flexible sealing region. V r The volume fraction of flexible material gradually decreases from 100% to 0%. V f Gradually increases from 0% to 100%. Optionally, the volume fraction of rigid material at each position in the middle And the volume fraction of flexible material Can be determined according to the following formula:

[0064]

[0065]

[0066] Wherein, L The length of the stress gradient line where the arbitrary position is located; xThis represents the distance from any location along the stress gradient line to the rigid support region at one end of the stress gradient line. This formula uses the rigid material as a reference point and employs trigonometric functions to smoothly transition the material ratio and hardness, effectively avoiding abrupt changes in material composition around the rigid material. Compared to linear formulas, this formula provides a smoother material transition, further improving the stability of the interface between different materials. In actual printing, the selection of a single layer of material can be determined based on both the material mixing accuracy and the calculated volume fraction.

[0067] In particular, due to the irregular shape of the earmold, the following two special cases may be encountered in the process of determining the volume fraction:

[0068] Scenario 1: A certain mesh sequence belongs to multiple stress gradient lines. For example, in a section of the ear mold where the mesh narrows, if the stress gradient lines are determined starting from the wider part of the mesh, multiple stress gradient lines may merge into one at the narrowing point. In this case, when calculating the volume fraction, the shortest gradient line among all the gradient lines passing through the merging section should be prioritized, and its length should be used as the length in the above formula. L First, the volume fraction is determined for each grid along the gradient line. This is because the shortest stress gradient line is most likely to experience abrupt material changes, and prioritizing a uniform material change along this direction is more conducive to a smooth transition of the entire earmold. Once the volume fraction of the confluence section (also called the confluence segment) is determined, for other stress gradient lines derived from this confluence segment along the gradient direction of decreasing stress, the derived portion can be called the residual segment, and the volume fraction of the material at the intersection of the confluence segment and the residual segment is used. V r0 Using the reference point, the material volume fraction of each grid in the remaining segment is determined using the following formula:

[0069]

[0070]

[0071] At this time L The length of the remaining segment. x This represents the distance from any position in the remaining segment to the intersection point along the direction of the other stress gradient lines.

[0072] Case two, a certain grid sequence does not belong to any stress gradient line. For example, in the ear mold, the part from narrow to wide, if the grid of the narrow part is taken as the starting point to determine the stress gradient line, a part of the grid may not belong to any stress gradient line in the structure. At this time, any point in these grids can be taken as the starting point to re-extend the stress gradient line along the stress rising and / or falling gradient direction, and connect these gradient lines with the grids with the closest stress value around them, and merge into the existing stress gradient line. At this time, the distribution of stress gradient lines and grids changes to case one, which can continue to be processed in the manner of case one.

[0073] S150, according to the volume fraction, and the printing energy density of the rigid support area and the flexible sealing area, determine the printing energy density at each position in the transition area.

[0074] Based on the above-mentioned volume fraction, the present embodiment can carry out the printing material ratio of multi-material DLP. According to the region characteristics, match the photosensitive resin combination (such as high rigidity resin, flexible thermoplastic polyurethane rubber resin, biocompatible resin, etc.) in the material library; and at the junction of the rigid area and the flexible area, the stress concentration is avoided by gradually changing the material ratio.

[0075] In addition, multi-material DLP printing process planning can also be carried out. Using digital micromirror device and ultraviolet LED array (wavelength 365nm / 405nm dual band), through mask pattern real-time refreshing (refresh rate ≥120Hz) control different area solidification depth (50-200μm). Through multi-material DLP printing control method, selective solidification for different regions: such as using 405nm (nanometer) high energy curing (energy density 20mJ / cm², millijoule per square centimeter) in rigid area; using 365nm low energy curing (energy density 8mJ / cm²) in flexible area to avoid brittle due to excessive crosslinking; at the material junction (such as rigid→flexible transition area), through gray mask (gray value 50-200) to realize the gradient distribution of exposure energy, forming interpenetrating network structure.

[0076] In summary, the overall printing control strategy in the above example is:

[0077] Rigid area: 405nm wavelength, energy density E r =20mJ / cm 2 ;

[0078] Flexible area: 365nm wavelength, energy density E f =8mJ / cm 2 ;

[0079] Transition zone exposure energy Etransition Proportionally weighted by materials: .

[0080] After the calculation, according to the printing energy density of each grid position of the three-dimensional numerical model, the gray mask of the printing surface is constructed layer by layer; in the DLP three-dimensional printing, according to the volume fraction of the two materials at each grid position, the material ratio at each grid position is controlled, and at the same time, according to the gray mask of each printing surface, the curing depth of the digital micromirror device and the ultraviolet LED array is controlled, to realize seamless hardness gradient inside the same layer printing surface (as shown in Figure 6 ), and hardness gradient between different layers of printing surface (as shown in Figure 7 ).

[0081] Further, the ear mold support structure adopts water-soluble photosensitive resin, and its printing parameters can be optimized synchronously with the main body structure. After multi-material DLP printing, a soluble support structure design can be used to optimize the support layout to reduce post-processing damage.

[0082] To sum up, the embodiment provides an individualized ear mold integrated manufacturing method based on multi-material digital light processing. First, the numerical model of the ear mold is subjected to dynamic stress analysis according to the actual wearing condition of the hearing aid, and different material regions (including rigid support region, flexible sealing region and material transition region) are automatically divided according to the stress analysis result, so as to improve the matching accuracy of the region division and the actual stress condition of the hearing aid. Then, the material ratio of the material transition region is optimized by using the stress gradient line, so as to better fit the irregular shape of the hearing aid and realize the fine transition of materials and hardness. The trigonometric function ratio mode with the rigid material region as the reference point realizes better smooth transition and fully guarantees the stability of material connection. Finally, based on the printing material distribution, the multi-material DLP printing method and the dynamic mask technology are used to control the light curing wavelength of different regions, so as to realize the material forming with sub-millimeter level precision, and truly realize the seamless material gradient inside the same printing layer and the material gradient between the printing layers. The method of the embodiment is suitable for custom hearing aids, including ear-back ear mold and custom shell, etc. The ear mold manufacturing period can be shortened to 4 hours, the tensile strength is improved by 30%-50%, the elastic modulus of the sealing region can be adjusted in the range of 0.5-5MPa, the residual rate of the support structure is less than 0.1%, and the surface roughness Ra is less than 10μm. The period and quality of the individualized ear mold customization are greatly improved, and the patient experience is improved.

[0083] Figure 8 A structural schematic diagram of an electronic device provided by the embodiment of the present application is shown in Figure 8 , which includes a processor 60, a memory 61, an input device 62 and an output device 63; the number of processors 60 in the device can be one or more, Figure 8The processor 60 in the device is taken as an example; the processor 60, the memory 61, the input device 62 and the output device 63 in the device can be connected through a bus or other means, Figure 8 The connection through the bus is taken as an example.

[0084] The memory 61 can be used for storing software programs, computer executable programs and modules, such as program instructions / modules corresponding to the personalized ear mold integrated manufacturing method based on multi-material digital light processing in the embodiments of the present application. The processor 60 executes the software programs, instructions and modules stored in the memory 61, thereby performing various function applications and data processing of the device, that is, realizing the personalized ear mold integrated manufacturing method based on multi-material digital light processing.

[0085] The memory 61 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system and at least one application program required by a function; the data storage area can store data created according to the use of the terminal and the like. In addition, the memory 61 can include a high-speed random access memory, and can also include a non-volatile memory, for example, at least one magnetic disk storage device, a flash memory device or other non-volatile solid-state memory device. In some examples, the memory 61 can further include a memory remotely arranged with respect to the processor 60, and these remote memories can be connected to the device through a network. Examples of the above network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network and a combination thereof.

[0086] The input device 62 can be used to receive input digital or character information, and to generate key signal input related to user settings and function control of the device. The output device 63 can include a display device such as a display screen.

[0087] The embodiments of the present application also provide a computer readable storage medium, which stores a computer program, and the program is executed by a processor to realize the personalized ear mold integrated manufacturing method based on multi-material digital light processing of any of the embodiments.

[0088] The computer storage medium of the embodiments of the present application can adopt any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may, for example, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or apparatus, or any combination thereof. More specific examples (non-exhaustive list) of the computer-readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, the computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus or device.

[0089] The computer-readable signal medium can include a data signal propagated in baseband or propagated as a carrier wave in a propagated data signal, in which the computer-readable program code is contained. Such propagated data signal can take a variety of forms, including but not limited to electro-magnetic, optical or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium that is not a storage medium and that can be used to carry or propagate program code for use by or in connection with an instruction execution system, apparatus or device.

[0090] The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wire line, optical fiber cable, RF, etc., or any suitable combination of the above.

[0091] The computer program code for carrying out operations of the present application can be written in one or more programming languages or combinations of languages including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0092] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present application.

Claims

1. A personalized earmold integrated manufacturing method based on multi-material digital light processing, characterized in that, The method comprises: obtaining a personalized earmold three-dimensional numerical model of a specific patient; adding static load based on the self-weight of a hearing aid and dynamic load based on periodic force of chewing motion to the numerical model, and performing dynamic stress analysis on the numerical model based on the added load; based on the stress analysis result, dividing material regions of different hardness in the numerical model, including rigid support region, flexible sealing region and transition region; determining the volume fraction of rigid material and flexible material for DLP three-dimensional printing at each position in the transition region according to the stress gradient line; determining the printing energy density at each position in the transition region according to the volume fraction, and the printing energy density of the rigid support region and the flexible sealing region; constructing a gray mask of the printing surface layer by layer according to the printing energy density of each grid position in the three-dimensional numerical model; in DLP three-dimensional printing, controlling the material ratio at each grid position according to the volume fraction of the two materials at each grid position, and controlling the wavelength curing depth according to the gray mask of each printing surface, so as to realize the hardness gradient inside the same layer and between different layers.

2. The method of claim 1, wherein the adding static load based on the self-weight of a hearing aid and dynamic load based on periodic force of chewing motion to the numerical model, and performing dynamic stress analysis under the added load comprises: setting the elastic modulus of the ear canal skin and the maximum occlusal force of chewing motion; setting the material model of the earmold as a linear elastic model, following the generalized Hooke's law; setting the interface fixed constraint on the part of the numerical model in contact with the hearing aid according to the actual wearing condition; uniformly applying the self-weight of the hearing aid as static load on the part of the numerical model in contact with the concha cavity; periodically applying the maximum occlusal force of chewing motion as dynamic load on the outer surface of the numerical model; performing dynamic stress analysis of the numerical model under the generalized Hooke's law based on the elastic modulus, interface fixed constraint and load.

3. The method of claim 1, wherein, The dividing material regions of different hardness in the numerical model based on the stress analysis result comprises: dividing the continuous region with Von Mises stress ≥ a first threshold value or contact pressure ≥ a second threshold value in the stress analysis into a rigid support region using rigid material; dividing the continuous region with a third threshold value ≤ contact pressure < the second threshold value and contact area with the ear canal ≥ a fourth threshold value into a flexible sealing region using flexible material.

4. The method of claim 1, wherein, The determining the volume fraction of rigid material and flexible material for DLP three-dimensional printing at each position in the transition region according to the stress gradient line comprises: extending the stress gradient line from an arbitrary position in the transition region along the gradient direction of stress rise and / or stress drop respectively until the stress gradient line intersects with a rigid support region and / or a flexible sealing region respectively; determining the volume fraction of rigid material and flexible material for DLP three-dimensional printing at the arbitrary position according to the length of the stress gradient line after intersection and the position of the arbitrary position in the stress gradient line after intersection.

5. The method of claim 4, wherein, The stress gradient line is extended from any position in the transition region along the direction of stress increase and / or stress decrease gradient respectively until the stress gradient line intersects with a rigid support region and / or a flexible sealing region respectively, including: Starting from any grid adjacent to a flexible sealing region in the transition region, a plurality of grids are determined step by step along the direction of stress increase gradient until the final grid intersects with a rigid support region; The grids determined step by step are connected in turn according to the order of monotonous stress increase to obtain a stress gradient line.

6. The method of claim 1, wherein, The volume fractions of rigid material and flexible material for DLP three-dimensional printing at each position in the transition region are determined according to the stress gradient line, including: The volume fraction of the rigid material at any position within the transition region for DLP three-dimensional printing is determined according to the following equation V r (x): wherein, L is the length of the stress gradient line where the arbitrary position is located; x represents the distance of the arbitrary position to the rigid support region at one end of the stress gradient line in the direction of the stress gradient line.

7. The method of claim 1, wherein, The rigid material includes glass fiber reinforced resin, and the flexible material includes organic silicon modified polyurethane acrylate.

8. An electronic device, comprising: It includes: One or more processors; Memory for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors implement the individual manufacturing method of the personalized ear mold based on multi-material digital light processing according to any one of claims 1-7.

9. A computer-readable storage medium, characterized in that, It has a computer program stored thereon, which is executed by a processor to implement the individual manufacturing method of the personalized ear mold based on multi-material digital light processing according to any one of claims 1-7.

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