Laser marking simulation method, parameter adjustment method and device, and electronic equipment

Abstract

The application discloses a kind of laser marking simulation method and device, the method includes: obtaining the finite element model including workpiece to be marked;Obtain laser scanning process parameters and the material information of the workpiece to be marked;Obtain the real-time marking position information of laser emission position and its scanning in laser marking simulation process;Based on the material information, laser scanning process parameters and position information obtained, the temperature of each node in the finite element model is obtained using the finite element thermal analysis of the finite element model, the purpose of simulation is realized to the laser marking of tooth appliance by finite element thermal analysis, correspondingly, a kind of laser marking parameter adjustment method and device, electronic equipment are also disclosed.

Description

Technical Field

[0001] This application relates to the field of orthodontic technology, and in particular to a laser marking simulation method, parameter adjustment method and device, and electronic equipment. Background Technology

[0002] In the existing manufacturing process of digital invisible aligners, the first step is to obtain a dental model corresponding to the patient through 3D printing technology. Then, the diaphragm is preheated, and then the preheated diaphragm and dental model are pressed together to obtain a shell-shaped diaphragm covering the surface of the dental model. Finally, the shell-shaped diaphragm is marked and cut.

[0003] To facilitate the acquisition of patients' medical information in a refined, personalized, and accurate manner, information such as the patient's personal information and current treatment stage is usually marked on the shell-shaped diaphragm during the marking process. Therefore, marking is a necessary step in the manufacturing process of invisible orthodontic appliances.

[0004] Laser marking is a marking method that uses a high-energy-density laser to locally irradiate a workpiece, causing the surface material to vaporize or undergo a chemical reaction that changes color, thereby leaving a permanent mark. Because there is no processing force between laser marking and the workpiece, it has advantages such as non-contact operation, no cutting force, minimal heat-affected zone, and the ability to preserve the original precision of the workpiece as much as possible. Therefore, laser marking is widely used in the manufacturing process of invisible orthodontic devices.

[0005] Generally speaking, for invisible aligners made of different materials, it is often necessary to continuously adjust some laser scanning process parameters during the marking process. Currently, in the laser marking process of aligners, the manufacturing personnel usually manually adjust the laser scanning process parameters based on the marking results. This makes the parameter adjustment operation during the marking process complicated and cumbersome, resulting in relatively low efficiency of laser marking. Summary of the Invention

[0006] The technical problem solved by this invention is to provide a laser marking parameter adjustment method, device, and electronic equipment, which automatically adjusts the laser scanning process parameters during the laser marking process for orthodontic appliances of different materials through finite element thermal analysis, reduces repeated manual adjustment operations during the marking operation, and solves the problem of low marking efficiency in the existing laser marking operation.

[0007] The technical problem solved by the present invention is to provide a laser marking simulation method and device, so as to achieve the purpose of simulating the laser marking of dental orthodontic appliances through finite element thermal analysis.

[0008] To achieve the above objectives, the present invention provides a laser marking simulation method, comprising:

[0009] Obtain the finite element model including the workpiece to be marked;

[0010] Obtain the laser scanning process parameters and the material information of the workpiece to be marked;

[0011] Obtain the laser emission position and real-time marking position information during the laser marking simulation process;

[0012] Based on the acquired material information, laser scanning process parameters, and location information, the temperature of each node in the finite element model is obtained through thermal analysis using the finite element model.

[0013] Optionally, obtaining the finite element model of the workpiece to be marked includes:

[0014] Based on the geometric information of the workpiece to be marked, a three-dimensional spatial geometric model is constructed by connecting key points, and then meshed to obtain the finite element model of the workpiece to be marked.

[0015] A finite element heat conduction control equation related to the material information of the workpiece to be marked is established for the finite element model, and the heat transfer boundary conditions and initial conditions on which solving the finite element heat conduction control equation depends are determined.

[0016] The heat transfer boundary conditions shall at least be selected as heat flux boundary conditions with a given laser heat flux density on the boundary of the finite element model.

[0017] Optionally, the determined heat transfer boundary conditions may also include temperature boundary conditions and / or convective heat transfer boundary conditions where some or all of the boundaries of the finite element model are at constant temperatures.

[0018] Optionally, the laser heat flux density of the heat flux boundary condition is determined as a heat flux density function related to the laser scanning process parameters, laser emission position, and real-time marking position.

[0019] Optionally, the laser heat flux density of the heat flux boundary condition is as follows:

[0020]

[0021] in, For a given heat flux density value on the heat transfer boundary that meets the aforementioned heat flux boundary conditions, η is the effective power coefficient; P0 is the heating power flux density; R is the laser spot radius; x, y, and z represent the laser emission position; x focus y focus and z focus These represent the coordinates of the real-time marking position.

[0022] Optionally, obtaining the laser emission position and its real-time marking position information during the laser marking simulation process includes:

[0023] The scanning path and total length are determined based on the marking information, and the scanning speed is obtained based on the set scanning time.

[0024] The coordinates of the laser emission position and the real-time marking position of the scan are obtained at different times during the scanning time based on the scanning speed.

[0025] Optionally, in the step of obtaining the temperature of each node in the finite element model by thermal analysis based on the acquired material information, scanning process parameters and position information, the transient temperature field of the workpiece to be marked is obtained by using an iterative method on the finite element model based on the acquired material information, laser scanning process parameters and position information, thereby obtaining the temperature of each node in the finite element model.

[0026] Optionally, the step of obtaining the transient temperature field of the workpiece to be marked by using an iterative method on the finite element model includes:

[0027] Configuration error tolerance;

[0028] The acquired material information, laser scanning process parameters, and position information are input into the finite element model. Based on the finite element heat conduction control equation, heat transfer boundary conditions, and initial conditions, the Gauss-Seidel iteration method is used to solve the transient temperature field and calculate the temperature of each node in the model.

[0029] The iteration stops when the error between two iterations is less than the error tolerance, and the temperature of each node of the finite element model is obtained.

[0030] Optionally, in the step of stopping the iteration when the error between two iterations is less than the error tolerance, the sum of the squares of the differences between the values ​​of the two iterations of all nodes is calculated, and the square root of the sum is taken as the error between the two iterations.

[0031] Optionally, the workpiece to be marked includes a dental mold and a diaphragm covering the dental mold, and the laser marking is performed on the surface of the diaphragm.

[0032] Optionally, the laser marking simulation method further includes:

[0033] The corresponding marking marks are determined based on the temperature of each node along the scanning path, and the laser marking simulation results are obtained.

[0034] Optionally, determining the corresponding marking mark based on the temperature of each node along the scanning path includes:

[0035] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0036] If the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, then the surface node is determined to be marked.

[0037] To achieve the above objectives, the present invention also provides a laser marking simulation device, comprising:

[0038] The finite element model acquisition module is used to acquire the finite element model including the workpiece to be marked;

[0039] The parameter acquisition module is used for laser scanning of process parameters and material information of the workpiece to be marked;

[0040] The position information acquisition module is used to obtain the real-time marking position information of the laser emission position and its scanning during the laser marking simulation process;

[0041] The analysis and processing module is used to obtain the temperature of each node in the finite element model by using thermal analysis based on the acquired material information, laser scanning process parameters and position information.

[0042] To achieve the above objectives, the present invention also provides a method for adjusting laser marking parameters, comprising:

[0043] The temperature of each node under each scanning path is obtained based on the above laser marking simulation method;

[0044] Determine whether a qualified marking mark is generated based on the temperature of each node under each scanning path.

[0045] Adjust the laser scanning process parameters based on the assessment results.

[0046] Optionally, determining whether a qualified marking mark is generated based on the temperature of each node along the obtained scanning path includes:

[0047] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece to be marked;

[0048] When the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, the surface node is determined to produce a qualified marking mark.

[0049] Optionally, determining whether a qualified marking mark is generated based on the temperature of each node along the obtained scanning path includes:

[0050] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece to be marked;

[0051] If the temperature of a surface node is greater than or equal to the vaporization temperature of the material, and at least one or more other nodes along the normal vector direction of the mesh plane of the finite element model have a temperature lower than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark.

[0052] Optionally, determining whether a qualified marking mark is generated based on the temperature of each node along the obtained scanning path includes:

[0053] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0054] If the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material of the workpiece to be marked, and the temperature of the adjacent node along the direction of the normal vector of the mesh plane of the finite element model is less than the vaporization temperature of the material, the surface node is determined to produce a qualified marking mark.

[0055] Optionally, adjusting the laser scanning process parameters based on the judgment result includes:

[0056] When the proportion of surface nodes that produce qualified marking marks to all surface nodes under each scanning path is less than a preset threshold, the laser scanning process parameters are adjusted until the proportion of surface nodes that produce qualified marking marks to all surface nodes under each scanning path is greater than or equal to the preset threshold, thus obtaining the adjusted laser scanning process parameters.

[0057] Optionally, the laser marking parameter adjustment method further includes:

[0058] Configure the adjustment range of the laser scanning process parameters, obtain the laser scanning process parameters within the adjustment range to perform laser marking simulation, and adjust the laser scanning process parameters.

[0059] To achieve the above objectives, the present invention also provides a laser marking parameter adjustment device, comprising:

[0060] The finite element model acquisition module is used to acquire the finite element model including the workpiece to be marked;

[0061] The parameter acquisition module is used for laser scanning of process parameters and material information of the workpiece to be marked;

[0062] The position information acquisition module is used to obtain the real-time marking position information of the laser emission position and its scanning during the laser marking simulation process;

[0063] The analysis and processing module is used to obtain the temperature of each node in the finite element model by using thermal analysis based on the acquired material information, laser scanning process parameters and position information.

[0064] The judgment module is used to determine whether a qualified marking mark is generated based on the temperature of each node under each scanning path.

[0065] The parameter adjustment processing module is used to adjust the laser scanning process parameters based on the judgment results.

[0066] To achieve the above objectives, embodiments of this application also propose an electronic device, the device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the laser marking parameter adjustment method as described above.

[0067] Compared with existing technologies, the laser marking simulation method, parameter adjustment method and device, and electronic equipment provided by this invention have the following advantages:

[0068] 1. This invention utilizes finite element thermal analysis to obtain the temperature of each node in the finite element model during the marking simulation process. Based on the obtained temperature of each node under each scanning path, it determines whether a marking mark is generated, and then determines whether the marking is qualified. If the marking is deemed unqualified, the laser scanning process parameters are adjusted and the simulation is repeated until the marking is qualified. Finally, the optimal laser marking process parameters for the workpiece to be marked are obtained, which solves the problem that the laser scanning process parameters in the laser marking process need to be constantly adjusted manually for personalized orthodontic appliances of different materials, and improves the efficiency of orthodontic appliance manufacturing.

[0069] 2. When determining whether the marking is qualified, the present invention determines that the surface node produces a qualified marking mark only when the surface node temperature is greater than or equal to the vaporization temperature of the material, and at least one or more nodes along the normal vector direction of the mesh plane of the finite element model have a temperature lower than the vaporization temperature of the material, or the temperature of the adjacent node is lower than the vaporization temperature of the material. This can minimize the impact of laser marking on the orthodontic function of shell-shaped dental appliances.

[0070] 3. This invention establishes a finite element model of the workpiece to be marked, and uses finite element thermal analysis to solve the instantaneous temperature field of the finite element model during the laser marking simulation process. The temperature of each node in the finite element model is obtained. The laser marking simulation results are obtained by comparing the temperature of each node with the vaporization temperature of the material of the workpiece to be marked. The results can be visualized and output, thus realizing the simulation of laser marking of dental orthodontic appliances. Attached Figure Description

[0071] One or more embodiments are illustrated by way of example with reference to the accompanying drawings, and these illustrative descriptions do not constitute a limitation on the embodiments.

[0072] Figure 1 This is a flowchart of the laser marking simulation method according to Embodiment 1 of this application;

[0073] Figure 2 This is a schematic diagram of the laser marking simulation result output of Embodiment 1 of this application;

[0074] Figure 3 This is a flowchart of the laser marking parameter adjustment method according to Embodiment 2 of this application;

[0075] Figure 4 This is an image showing the effect of marking the target workpiece using the adjusted laser scanning process parameters in Embodiment 2 of this application.

[0076] Figure 5 This is a structural diagram of the laser marking simulation device according to Embodiment 3 of this application;

[0077] Figure 6 This is a structural diagram of the laser marking parameter adjustment device according to Embodiment 4 of this application;

[0078] Figure 7 This is a schematic diagram of the structure of the electronic device according to Embodiment 5 of this application. Detailed Implementation

[0079] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the various embodiments of this application to help readers better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments. The division of the various embodiments below is for the convenience of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0080] To enable automated and customized production of orthodontic appliances, the required processes generally include printing dental models, cleaning, curing, molding, cutting, and packaging. For ease of understanding, this embodiment first provides a brief introduction to the manufacturing process of shell-shaped orthodontic appliances:

[0081] When fabricating orthodontic appliances, the patient's mouth is first scanned to obtain a digital 3D model of the teeth. Then, a theoretical model (digital dental model, not a physical model) is generated for each treatment stage, and the corresponding physical dental model is printed. Next, a preheated thermoforming film is pressed onto the dental model. At this point, the thermoforming film attached to the dental model surface becomes a shell-shaped film. The workpiece to be marked is a semi-finished shell-shaped orthodontic appliance, combining the shell-shaped film with the dental model. In subsequent processes, the semi-finished product undergoes marking, cutting, and demolding to finally become the finished shell-shaped film, i.e., the finished shell-shaped orthodontic appliance. The marking operation typically involves marking the shell-shaped film on the dental model surface. Because orthodontic appliances are customized products, each appliance has a unique structure. To differentiate each orthodontic appliance, a corresponding label needs to be printed on it for subsequent identification. This label includes, but is not limited to, identity information (a unique ID), the patient's name, treatment period, age, product logo, QR code, barcode, or corresponding illustration, or a combination of the above. Among them, the identity information is a unique identifier that matches the patient's basic information one by one. The patient's basic information includes information on the raw materials used in the orthodontic appliance manufacturing process, processing technology information, workstation flow information, and the patient's basic information (including case type, age, address, etc.). The label enables subsequent information binding, providing a reliable guarantee for efficient sorting and delivery.

[0082] Generally, the laser scanning process parameters, such as laser spot radius, heating power flux density, and effective power coefficient, differ for orthodontic appliances made of different materials. Therefore, some laser scanning process parameters need to be adjusted during the marking process of orthodontic appliances made of different materials. Currently, the marking is often achieved by manually adjusting these parameters during the laser marking process, which reduces the efficiency of laser marking. Based on this, the present invention provides a laser marking simulation method, parameter adjustment method and device, and electronic equipment. By constructing a finite element model of the target orthodontic appliance to be marked, the thermal analysis of the finite element model is used to simulate the laser marking results and adjust the parameters, thereby reducing the labor costs in the laser marking process and improving the efficiency of laser marking of orthodontic appliances.

[0083] The implementation details of the server grouping method described in this application will be specifically described below with reference to specific embodiments. The following implementation details are provided for ease of understanding only and are not necessary for implementing this solution.

[0084] Example 1

[0085] This embodiment provides a laser marking simulation method, the process of which is as follows: Figure 1 The laser marking simulation method can be used to simulate laser marking on a target orthodontic appliance. In this embodiment, the laser marking simulation method can be applied to terminals with communication, computing, and data storage capabilities, such as computers, mobile phones, and other electronic devices. It includes the following steps:

[0086] Step 101: Obtain the finite element model including the workpiece to be marked.

[0087] In this embodiment of the invention, the workpiece to be marked is a shell-shaped orthodontic appliance including a dental model and a diaphragm covering the dental model, which will also be referred to as the target orthodontic appliance to be marked.

[0088] In this embodiment, obtaining a finite element model including the workpiece to be marked includes:

[0089] Based on the geometric information of the workpiece to be marked, a three-dimensional spatial geometric model is constructed by connecting key points, and then meshed to obtain the finite element model of the workpiece to be marked.

[0090] A finite element heat conduction control equation related to the material properties of the workpiece to be marked is established for the finite element model, and the heat transfer boundary conditions and initial conditions on which solving the finite element heat conduction control equation depends are determined to obtain the finite element thermal analysis calculation model.

[0091] In this embodiment, the workpiece to be marked is a shell-shaped orthodontic appliance including a dental model and a diaphragm covering the dental model. The marking operation is generally performed on the diaphragm covering the dental model. Therefore, the information block to be marked is set on the diaphragm. In this embodiment, the geometric information of the workpiece to be marked can come from the data obtained during the fabrication of the target orthodontic appliance, or it can be obtained by scanning the target orthodontic appliance with a scanning device such as a scanner. That is to say, in some embodiments, since the fabrication of the orthodontic appliance necessarily requires obtaining its geometric dimension information, and the geometric dimension information must exist during the fabrication of the orthodontic appliance, when establishing the finite element model of the target orthodontic appliance to be marked, the geometric dimension information obtained during the fabrication of the target orthodontic appliance to be marked can be directly obtained. The obtained geometric dimension information is imported into finite element analysis (FEA) software (such as finite element analysis software Abaqus, Ansys). In the finite element analysis software, geometric surfaces are generated based on the connection of key points, and then geometric bodies are generated from the geometric surface information, thereby establishing a three-dimensional spatial geometric model. The model is then meshed using mesh generation to obtain the finite element model of the target orthodontic appliance to be marked. Since the specific construction process of the finite element model is already existing technology, it will not be elaborated here.

[0092] In other embodiments, when constructing the finite element model of the target orthodontic appliance to be marked, the target orthodontic appliance to be marked can also be scanned by a scanner (scanning the dental model and the diaphragm separately) to obtain the geometric dimension information of the target orthodontic appliance to be marked. Then, the obtained geometric dimension information of the target orthodontic appliance to be marked is imported into finite element analysis software (such as finite element analysis software Abaqus or Ansys). Similarly, in the finite element analysis software, geometric surfaces are generated based on the connection of key points, and then geometric bodies are generated from the geometric surface information to establish a three-dimensional spatial geometric model. The three-dimensional spatial geometric model is then meshed using mesh generation to obtain the finite element model of the target orthodontic appliance to be marked.

[0093] In the finite element analysis software, the element type used for mesh generation can be tetrahedral, but it should be noted that it is not limited to tetrahedral elements. Hexahedral elements can also be used, and even more than one element type can be used. The meshing information of the final generated finite element model includes, but is not limited to, element information, node information, and boundary information. The element information includes, but is not limited to, element number and nodes contained in the element. The node information includes, but is not limited to, node number and node coordinates. The boundary information includes, but is not limited to, element information and node information on the boundary.

[0094] The purpose of this invention is to simulate laser marking results using thermal analysis of a finite element model. Since finite element thermal analysis is based on the heat balance equation of the energy conservation principle, the finite element method calculates the temperature of each node inside the object and derives other thermophysical parameters. Therefore, to achieve finite element thermal analysis, after obtaining the finite element model of the target orthodontic device to be marked, a finite element heat conduction control equation related to the material properties of the workpiece to be marked (i.e., the target orthodontic device) must be established based on the energy conservation principle. The material properties of the target orthodontic device include, but are not limited to, the material density, specific heat capacity, and thermal conductivity along different directions. The basic variable of the finite element heat conduction control equation is temperature T. In this embodiment, based on Fourier's law of heat transfer and the law of energy conservation, the finite element heat conduction control equation shown in Formula 1 is established as follows:

[0095]

[0096] Where T is the temperature at geometric position (x, y, z), which is a function of geometric position (x, y, z) and time t, in K; ρ is the material density of the object in the model, in kg / m³; Кx, Кy, and Кz are the thermal conductivity of the object in the model along the x, y, and z directions, respectively, in W / (m*K); c TLet be the specific heat capacity of the material in the model, in J / (kg*K); Q is the heat source inside the structure, in W / kg. The heat source Q inside the structure refers to the heat of the heating object inside the model. If there is no heating object, then Q is 0. In this embodiment of the invention, it is assumed that there is no heating object inside the workpiece to be marked, i.e., the target orthodontic appliance to be marked. Therefore, its finite element heat conduction control equation can be simplified to:

[0097]

[0098] In this embodiment, the finite element thermal analysis is based on solving the aforementioned finite element heat conduction control equation to obtain the temperature of each node inside the object that forms the finite element model. However, solving the aforementioned finite element heat conduction control equation also depends on heat transfer boundary conditions and initial conditions. Therefore, after determining the aforementioned finite element heat conduction control equation, it is necessary to determine the heat transfer boundary conditions used to solve the finite element heat conduction control equation. In the finite element thermal analysis, the heat transfer boundary conditions used include:

[0099] 1. Temperature boundary conditions

[0100] The temperature boundary condition is defined by determining that the temperature function on the boundary of the finite element model is a known function that varies with location but not with time. For example, the specific form of the temperature boundary condition is as follows:

[0101]

[0102] Where T(x,y,z,t) is the temperature T in Formula 2, that is, the temperature at the geometric position (x,y,z). The temperature given on the heat transfer boundary to meet the first type of boundary condition is essentially a constant temperature for a certain geometric location. In general, this type of boundary condition is an ideal boundary condition.

[0103] 2. Heat flux boundary conditions

[0104] The heat flux boundary conditions are defined by using the heat flux density function on the boundary of the given finite element model. For example, the heat flux boundary conditions can take the following form:

[0105]

[0106] in, The heat flux density given on the heat transfer boundary to meet the second type of boundary conditions is expressed in W / m³. 2 n x n y n z , where are the direction cosines of the outward normal at the geometric position (x, y, z) in the model, and t is time, in seconds.

[0107] 3. Convective heat transfer boundary conditions

[0108] The convective heat transfer boundary condition mainly considers whether there is wind or heat convection in the environment where the object is located. It is mainly based on the given ambient temperature and heat transfer coefficient for convective heat transfer as boundary conditions. For example, the convective heat transfer boundary condition takes the following form:

[0109]

[0110] in, The convective heat transfer coefficient between the object and the surrounding medium, expressed in W / (m²). 2 *K); T ∞ The ambient temperature is expressed in Kelvin (K).

[0111] In this embodiment, based on the finite element heat conduction control equation, appropriate heat transfer boundary conditions are selected to establish the finite element thermal analysis calculation model. Specifically, in actual operation, appropriate boundary conditions can be selected from the above-mentioned temperature boundary conditions, heat flux boundary conditions with a given heat flux density, and convective heat transfer boundary conditions considering convective heat transfer, according to the actual processing and production process of the orthodontic appliance. In this embodiment, since the purpose of this invention is to simulate the laser marking process, at least a heat flux boundary condition with a given heat flux density on the boundary of the finite element model is selected, and the heat flux boundary condition is determined to be the heat flux density of the laser.

[0112] Furthermore, in this embodiment, the laser heat flux density of the heat flux boundary condition can be determined as a function related to the laser scanning process parameters, the laser emission position, and the real-time marking position.

[0113] The heat flux density of the laser can be the heat flux density of a Gaussian laser heat source, an ellipsoidal laser heat source, or other laser heat sources, and can be determined according to the actual situation. This invention is not limited to this. In this embodiment, the heat flux density of the laser is a Gaussian laser heat source, and it is determined as a function related to the laser scanning process parameters, the laser emission position, and the real-time marking position. The specific expression is as follows:

[0114]

[0115] in, To meet the given heat flux density value at the heat transfer boundary condition, η is the effective power coefficient in the laser scanning process parameters; P0 is the heating power flux density in the laser scanning process parameters, in W / m³. 2 R is the laser spot radius in the laser scanning process parameters; x, y, and z represent the position coordinates of the laser emission location; x focus y focus and zfocus These represent the real-time marking position coordinates of the laser marking.

[0116] Solving the finite element heat conduction governing equations requires determining not only the heat transfer boundary conditions but also the initial heat transfer conditions. In this embodiment of the invention, the initial conditions are determined as follows:

[0117]

[0118] in, This represents the initial temperature of the object in the finite element model, i.e., the target orthodontic appliance to be marked, in K.

[0119] Optionally, besides selecting the heat flux boundary condition with a given heat flux density on the boundary of the finite element model as the heat transfer boundary condition of the finite element model, this embodiment can also use the heat flux boundary condition with a given heat flux density on the boundary of the finite element model and the temperature boundary condition with some or all of the boundaries at a constant temperature as the heat transfer boundary condition, so as to make the transient temperature field obtained by the thermal analysis of the finite element model more accurate and improve the accuracy of laser marking simulation. That is, in this embodiment, the step of determining the heat transfer boundary condition on which the solution of the finite element heat conduction control equation depends may further include:

[0120] The heat transfer boundary conditions are selected as follows: a heat flux boundary condition with laser heat flux density on the boundary of the given finite element model and a temperature boundary condition with some or all of the boundary at a constant temperature.

[0121] The heat flux density of the laser can be the heat flux density of a Gaussian laser heat source, the heat flux density of an ellipsoidal laser heat source, or the heat flux density of other laser heat sources. This invention is not limited to these.

[0122] In this embodiment, the constant temperature can refer to a temperature that does not change over time, but for different nodes on the boundary, the temperature can vary with location. Specifically, setting part or all of the boundary as a constant temperature is a temperature boundary condition, which can take the following form:

[0123]

[0124] in, A known temperature function that varies with position but not with time on the heat transfer boundary to satisfy the temperature boundary condition.

[0125] Of course, in specific applications, the boundary nodes in the finite element model can be determined according to the actual situation to determine which boundary nodes are at constant temperature, thereby determining the temperature boundary conditions.

[0126] The laser heat flux density of the heat flux boundary condition is determined as a function related to the laser scanning process parameters, laser emission position, and real-time marking position.

[0127] As can be seen, this embodiment can select the heat flux density of the laser and convert it into a heat flux density function related to the laser scanning process parameters, the laser emission position, and the real-time marking position. This function is then combined with a temperature boundary condition that sets some or all of the boundaries at a constant temperature as the heat transfer boundary condition for the finite element model thermal analysis. This determines the function as a function related to the laser emission position and the real-time marking position, making the transient temperature field obtained by the finite element model thermal analysis more accurate, thereby making the laser marking simulation results more realistic.

[0128] Optionally, besides selecting the heat flux boundary condition with a given heat flux density on the boundary of the finite element model as the heat transfer boundary condition of the finite element model, this embodiment can also use the heat flux boundary condition with a given heat flux density on the boundary of the finite element model and the convective heat transfer boundary condition considering convective heat transfer together as the heat transfer boundary condition, so as to consider the influence of thermal convection in the finite element thermal analysis, making the obtained transient temperature field more realistic and improving the accuracy of laser marking simulation. That is, in this embodiment, the step of determining the heat transfer boundary condition on which the solution of the finite element heat conduction control equation depends may further include:

[0129] The heat transfer boundary conditions are selected as the heat flux boundary conditions, which are the laser heat flux density boundary conditions on the given finite element model boundary and the convective heat transfer boundary conditions considering convective heat transfer.

[0130] Since the manufacturing environment of orthodontic appliances may also be affected by thermal convection, the heat transfer boundary conditions of the finite element model should be further considered in light of the influence of ambient wind and thermal convection during the marking and laser scanning processes. To make the laser marking simulation process more realistic, in this embodiment, both the convective heat transfer boundary conditions considering convective heat transfer and the convective heat transfer boundary conditions considering convective heat transfer are used as the heat transfer boundary conditions. The specific form of the convective heat transfer boundary conditions considering convective heat transfer is as follows:

[0131]

[0132] in, T is the convective heat transfer coefficient between the object and the surrounding medium. ∞ The ambient temperature is expressed in Kelvin (K).

[0133] The laser heat flux density of the heat flux boundary condition is determined as a function related to the laser scanning process parameters, laser emission position, and real-time marking position.

[0134] As can be seen, this embodiment can select the heat flux density of the laser and convert it into a function related to the laser scanning process parameters, the laser emission position and the real-time marking position. Combined with the convective heat transfer boundary conditions that consider convective heat transfer as the heat transfer boundary conditions for the thermal analysis of the finite element model, the transient temperature field obtained by solving the finite element model can be more accurate by considering the influence of wind and thermal convection in the laser marking simulation process of the orthodontic device marking and the laser scanning environment.

[0135] Optionally, besides selecting the heat flux boundary condition with a given heat flux density on the boundary of the finite element model as the heat transfer boundary condition of the finite element model, this embodiment can also use the heat flux boundary condition with a given laser heat flux density on the boundary of the finite element model, the temperature boundary condition with some or all boundaries at a constant temperature, and the convective heat transfer boundary condition considering convective heat transfer as the heat transfer boundary condition, so as to make the transient temperature field obtained by laser marking simulation more accurate and improve the accuracy of laser marking simulation. That is, in this embodiment, the step of determining the heat transfer boundary condition on which the solution of the finite element heat conduction control equation depends may further include:

[0136] The heat transfer boundary conditions are selected as follows: heat flux boundary conditions with given heat flux density on the boundary of the finite element model, temperature boundary conditions with some or all of the boundary being at constant temperature, and convective heat transfer boundary conditions considering convective heat transfer.

[0137] The laser heat flux density of the heat flux boundary condition is determined as a heat flux density function related to the laser scanning process parameters, laser emission position, and real-time marking position.

[0138] As can be seen, this embodiment can select the heat flux density of the laser and convert it into a function related to the laser scanning process parameters, the laser emission position, and the real-time marking position. It can then combine this function with temperature boundary conditions that keep some or all of the boundaries at a constant temperature, as well as convective heat transfer boundary conditions that consider convective heat transfer. This approach also takes into account the ideal state and the effects of wind and thermal convection in the marking and laser scanning environments of the orthodontic device. As a result, the transient temperature field obtained by solving the finite element model can be more accurate, and the laser marking simulation results can be more realistic.

[0139] Step 102: Obtain the laser scanning process parameters and the material properties of the workpiece to be marked.

[0140] In this embodiment of the invention, the laser scanning process parameters include, but are not limited to, the laser spot radius R, the heating power flux density P0, and the effective power coefficient η. In one example, the laser scanning process parameters can be manually input by the human-machine interface of the terminal using this invention. When it is necessary to simulate marking the target orthodontic appliance, the laser scanning process parameters are set through the human-machine interface to obtain the laser scanning process parameters. However, the laser scanning process parameters can also be obtained by the electronic device using this invention through wireless communication, such as a user sending the laser scanning process parameters to the electronic device using this invention via a smartphone. This invention is not limited to this method of obtaining laser scanning process parameters.

[0141] In this embodiment of the invention, the material properties of the workpiece to be marked include material density, specific heat capacity, and thermal conductivity in different directions. Since the target orthodontic appliance to be marked includes a dental model and a diaphragm covering the dental model, and generally the material properties of the dental model and the diaphragm are not the same, obtaining the material properties of the workpiece to be marked includes obtaining the material properties of both the diaphragm covering the dental model and the dental model itself. The material properties can be obtained by user pre-input or setting, and this invention is not limited thereto.

[0142] Step 103: Obtain the laser emission position and the real-time marking position information of the laser scanning during the laser marking simulation process.

[0143] In this embodiment of the invention, the aim is to simulate and predict laser marking for each orthodontic appliance. Therefore, it is necessary to simulate a real laser marking module to mark the workpiece to be marked, and print the corresponding marking mark in the marking area of ​​the workpiece to be marked, that is, in the marking information block of the target orthodontic appliance to be marked. The marking mark includes, but is not limited to, identity information (unique ID information), patient's name, treatment period, age information, product logo, and QR code, barcode, or corresponding icon, etc., or combinations of the above information, including text, numbers or letters, or combinations thereof.

[0144] The laser emission position refers to the emission position of the simulated laser. This position is related to the marking information to be marked in the information block to be marked. During laser marking simulation, the laser emission position needs to be adjusted in real time according to the marking information to a position that meets the marking focus position information. In this embodiment of the invention, the marking information refers to the information including the marking mark to be printed in the information block to be marked and its corresponding positioning mark. The real-time marking position information refers to the real-time position coordinates of the laser reaching the information block to be marked on the film at different times. The real-time marking position is also related to the marking information and the position of the information block to be marked.

[0145] In some embodiments, the laser emission position and the real-time marking position information of the scan can be obtained in the following way: determine the scanning path and total length based on the marking information, and obtain the scanning speed based on the set scanning time; obtain the laser emission position and the real-time marking position coordinates of the scan at different times within the scanning time based on the scanning speed, that is, pre-set the total scanning time, then obtain the marking information, determine the marking starting point, determine the scanning path and total length based on the marking information, calculate the scanning speed based on the determined scanning path and total length, and calculate the laser emission position and the real-time marking position coordinates of the scan at different times within the scanning time based on the scanning speed.

[0146] Specifically, in step 103, when performing a marking simulation on the target orthodontic appliance to be marked, marking information is first acquired. This marking information can be preset by the user and includes information about the marking mark and its corresponding positioning mark. The marking start point can be set manually. The scanning path and total length are determined based on the marking information. Then, based on the preset total scanning time, the scanning speed is calculated based on the scanning path and total length determined by the marking information. The laser emission position and the real-time marking position coordinates at different times during the scanning time are calculated. Based on the obtained real-time marking position information, the marking mark is printed into the marking information block of the target orthodontic appliance to be marked.

[0147] Step 104: Based on the obtained material properties of the workpiece to be marked, laser scanning process parameters and corresponding position information, the temperature of each node in the finite element model is obtained by thermal analysis using the finite element model.

[0148] In this embodiment of the invention, based on the laser scanning process parameters and the material properties of the workpiece to be marked obtained in step 102, and the laser emission position and real-time marking position information of the marking simulation process obtained in step 103, the transient temperature field is solved by an iterative method based on the finite element calculation model in step 101, namely the finite element heat conduction control equation, heat transfer boundary conditions and initial conditions, to obtain the transient temperature field of the finite element model of the workpiece to be marked during the laser marking simulation process, thereby obtaining the temperature of each node in the finite element model.

[0149] In one example of the present invention, obtaining the transient temperature field of the workpiece to be marked by using an iterative method on the finite element model includes:

[0150] Configure an error tolerance; the error tolerance is the condition for stopping the iteration of the iterative method, and its value can be preset according to the calculation accuracy requirements. In this embodiment, the error tolerance can be set to 0.001, but the present invention is not limited thereto.

[0151] The acquired material properties of the workpiece to be marked, laser scanning process parameters, and corresponding position information are input into the finite element model. Based on the finite element heat conduction control equation, heat transfer boundary conditions, and initial conditions, the Gauss-Seidel iterative method is used to solve the transient temperature field and calculate the temperature of each node in the model. In this embodiment, the acquired material properties, laser scanning process parameters, laser emission position information obtained at different times, and real-time marking position coordinates are input into the finite element heat conduction control equation, heat transfer boundary conditions, and initial conditions to calculate the temperature of each node in the finite element model.

[0152] The iteration error is calculated, and iteration stops when the iteration error is less than the error tolerance, thus obtaining the temperature of each node in the finite element model. In one example, the iteration error can be the weighted sum of the differences between two iterations for all nodes. That is, when proceeding to the nth iteration, the difference between the temperatures of all nodes obtained in the nth iteration and the corresponding temperatures of all nodes obtained in the (n-1)th iteration is calculated, and the weighted sum of these differences is obtained to obtain the iteration error. Iteration stops when this iteration error is less than the error tolerance. In another example, the iteration error can be the square root of the sum of the squares of the differences between two iterations for all nodes. That is, the difference between the temperatures of all nodes obtained in the nth iteration and the corresponding temperatures of all nodes obtained in the (n-1)th iteration is calculated, the sum of the squares of these temperature differences is taken, and the square root is obtained to obtain the iteration error. Iteration stops when this iteration error is less than the error tolerance.

[0153] As can be seen, in this embodiment, a finite element model is established for the workpiece to be marked, i.e., the target corrector. Then, the instantaneous temperature field of the finite element model is solved by thermal analysis of the finite element model during the laser marking simulation process, and the temperature of each node in the finite element model is obtained, thereby realizing the simulation of laser marking.

[0154] Furthermore, in this embodiment, after step 104, the laser marking simulation method may further include:

[0155] Step 105: Determine the corresponding marking mark based on the temperature of each node under the scanning path to obtain the laser marking simulation result.

[0156] Generally, for nodes outside the scanning path, their temperature will not change since they are not irradiated by the laser. However, for nodes in the scanning path, if they are scanned by the laser, their temperature will exceed the vaporization temperature of the material in the scanning path. Therefore, it is possible to determine whether to generate a marking mark by comparing the temperature of the nodes in the scanning path with the vaporization temperature of the material to be marked.

[0157] In one example, step 105 further includes:

[0158] Based on the temperature of each node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0159] If the temperature of a certain node is lower than the vaporization temperature of the material of the corresponding workpiece to be marked, then it is determined that a marking mark will be generated for that node.

[0160] In this embodiment, since the information block to be marked is located on the diaphragm of the target orthodontic device, the material vaporization temperature of the corresponding workpiece to be marked refers to the material vaporization temperature of the diaphragm. Assuming the vaporization temperature of the diaphragm is 1000K, if the node temperature under the scanning path obtained through step 204 is greater than or equal to the material vaporization temperature of the diaphragm (1000K), it is considered that the material of the node on the scanning path has been removed, and the laser scanning has generated a permanent marking mark. Therefore, a marking mark is generated for the node. Otherwise, it is considered that the laser scanning has not generated a marking mark, and no marking mark is generated.

[0161] Since the finite element model constructed in this invention is a three-dimensional structure, its scanning path will have multiple layers of nodes. However, generally, it is only necessary to mark the surface nodes. Therefore, step 105 further includes:

[0162] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0163] If the temperature of a certain surface node is lower than the vaporization temperature of the material of the corresponding workpiece to be marked, a marking mark will be generated on that surface node.

[0164] Once the laser marking simulation results from step 105 are obtained through finite element thermal analysis, the final marking effect can be visualized via a corresponding terminal. This means the simulation results can be output and displayed. For example, consider the simulation results of planar laser marking on a diaphragm, where the marking is "123". The simulation result output would be as follows: Figure 2 As shown.

[0165] As can be seen, in this embodiment, a finite element model is established for the target orthodontic appliance to be marked. Then, the instantaneous temperature field of the finite element model is solved by thermal analysis of the finite element model during the marking simulation process. The temperature of each node in the finite element model is obtained. Based on the temperature of each node and the vaporization temperature of the material of the workpiece to be marked, it is determined whether a marking mark is generated. Thus, the laser marking simulation result is obtained and can be visualized and output. This achieves the purpose of laser marking simulation of shell-shaped orthodontic appliances. It allows users to evaluate the laser marking simulation effect and adjust the laser marking parameters of the target orthodontic appliance accordingly.

[0166] The third embodiment of this application provides a laser marking simulation method. In this embodiment, a heat flow boundary condition with a given heat flux density on the boundary of the finite element model and a temperature boundary condition with some or all of the boundaries at a constant temperature are selected as the heat transfer boundary conditions, so as to make the transient temperature field obtained by thermal analysis of the finite element model more accurate and improve the accuracy of laser marking simulation.

[0167] Example 2:

[0168] This embodiment provides a method for adjusting laser marking parameters, referencing... Figure 3 The laser marking parameter adjustment method can be applied to terminals with communication, computing, and data storage capabilities, such as computers, mobile phones, and other electronic devices, and includes:

[0169] Step 201: Obtain the finite element model including the workpiece to be marked;

[0170] Step 202: Obtain the laser scanning process parameters and the material properties of the workpiece to be marked;

[0171] Step 203: Obtain the laser emission position and the real-time marking position information during the laser marking simulation process;

[0172] Step 204: Based on the obtained material properties of the workpiece to be marked, laser scanning process parameters and corresponding position information, the temperature of each node in the finite element model is obtained by thermal analysis using the finite element model.

[0173] Steps 201-204 in this embodiment are similar to the corresponding steps in the aforementioned embodiment 1, and will not be repeated here.

[0174] Step 205: Determine whether a qualified marking mark is generated based on the temperature of each node under each scanning path.

[0175] Generally, for nodes outside the scanning path, their temperature will not change since they are not irradiated by the laser. However, for nodes in the scanning path, if they are scanned by the laser, the temperature of the node will exceed the vaporization temperature of the material in the scanning path. Therefore, it can be determined whether a qualified marking mark is generated by comparing the temperature of the node in the scanning path with the vaporization temperature of the workpiece material to be marked.

[0176] Furthermore, since the finite element model constructed in this invention is a three-dimensional structure, its scanning path will have multiple layers of nodes. However, generally, it is only necessary to mark the surface nodes. Therefore, in this embodiment, step 205 further includes:

[0177] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0178] When the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material of the corresponding workpiece to be marked, the surface node is determined to produce a qualified marking mark.

[0179] In this embodiment, since the information block to be marked is located on the diaphragm of the target orthodontic device, the material vaporization temperature of the corresponding workpiece to be marked refers to the material vaporization temperature of the diaphragm. Assuming the vaporization temperature of the diaphragm is 1000K, if the node temperature under the scanning path obtained through step 204 is greater than or equal to the material vaporization temperature of the diaphragm (1000K), it is considered that the material of the node on the scanning path has been removed, and the laser scan has generated a permanent marking mark. In this case, the node has generated a qualified marking mark. Otherwise, it is considered that the laser scan has not generated a qualified marking mark for the node.

[0180] In the laser marking process of shell-shaped orthodontic appliances, the general goal is to mark only the surface of the workpiece to be marked, i.e., the target appliance, and to avoid marking deep into the membrane or even penetrating it, thereby affecting the orthodontic effect of the target appliance. Therefore, optionally, to prevent the laser marking from penetrating the membrane of the target appliance, step 205 may further include:

[0181] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece to be marked;

[0182] If the temperature of a surface node is greater than or equal to the vaporization temperature of the material, and at least one or more other nodes along the normal vector direction of the mesh plane of the finite element model have a temperature lower than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark.

[0183] In this embodiment, the material vaporization temperature of the corresponding workpiece to be marked refers to the material vaporization temperature of the diaphragm. According to step 204, the temperature of each node in the finite element model can be obtained, thus obtaining the temperature of each surface node along each scanning path. Comparing each surface node with the material vaporization temperature of the diaphragm, if the surface node temperature is greater than or equal to the material vaporization temperature of the diaphragm, it is considered that the material at that surface node along the scanning path has been removed, and the laser scan has produced a permanent marking mark on that surface node. However, at this point, the laser scan may also scan the deeper layers of the diaphragm or even penetrate it. Therefore, it is necessary to further determine the direction of the laser irradiation. Whether other nodes also produce permanent markings is generally determined by the fact that the laser irradiation direction is parallel to the normal vector of each meshed unit plane in the finite element model. Therefore, in this embodiment, when it is determined that the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, it is also necessary to determine the temperature of other nodes along the normal vector direction of the mesh plane of the finite element model. If at least one or more of the other nodes along the normal vector direction of the mesh plane of the finite element model have a temperature lower than the vaporization temperature of the material, then it is determined that the surface node has produced a qualified marking to ensure that the diaphragm is not penetrated by laser scanning.

[0184] As can be seen, in this embodiment, when determining whether the marking is qualified, in addition to judging whether the temperature of each surface node under the scanning path is greater than or equal to the material vaporization temperature, it can further judge whether the temperature of other nodes along the normal vector direction of the mesh plane where the finite element model is located is greater than or equal to the material vaporization temperature. Only when the temperature of the surface node is greater than or equal to the material vaporization temperature, and at least one or more nodes along the normal vector direction of the surface node along the mesh plane where the finite element model is located have a temperature less than the material vaporization temperature, is it determined that the surface node has generated a qualified marking mark, so that the diaphragm will not be penetrated during the laser marking process.

[0185] However, in most cases, the marking information block for the target orthodontic appliance is located on the dentition section of the appliance. Therefore, during actual laser marking, it is necessary to mark only the surface of the diaphragm as much as possible to minimize any impact on the orthodontic effect of the target appliance. Therefore, optionally, to ensure that the laser marking only applies to the surface of the diaphragm, step 205 may further include:

[0186] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece to be marked;

[0187] If the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material of the workpiece to be marked, and the temperature of the adjacent node along the direction of the normal vector of the mesh plane of the finite element model is less than the vaporization temperature of the material, the surface node is determined to produce a qualified marking mark.

[0188] In this embodiment, the material vaporization temperature of the corresponding workpiece to be marked refers to the material vaporization temperature of the diaphragm. According to step 204, the temperature of each node in the finite element model can be obtained, thus obtaining the temperature of each surface node along each scanning path. Comparing each surface node with the material vaporization temperature of the diaphragm, if the surface node temperature is greater than or equal to the material vaporization temperature of the diaphragm, it is considered that the material at that surface node along the scanning path has been removed, and the laser scan has produced a permanent marking mark on that surface node. However, at this time, the laser scan may also scan deeper layers of the diaphragm. If the laser scans a deeper layer of the diaphragm, it may affect the correction. To avoid this situation, in this step, it is necessary to further determine whether other nodes in the laser irradiation direction have also produced permanent markings. Therefore, in this embodiment, when it is determined that the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, it is further determined that the temperature of the adjacent nodes of the surface node in the direction of the normal vector of the mesh plane of the finite element model is less than the vaporization temperature of the material. Then, it is determined that the surface node has produced a qualified marking. Otherwise, it is considered that the surface node has not produced a qualified marking.

[0189] As can be seen, in this embodiment, when determining whether the marking is qualified, in addition to judging whether the temperature of each surface node under the scanning path is greater than or equal to the material vaporization temperature, it further judges whether the temperature of the adjacent node of the surface node in the direction of the normal vector of the mesh plane of the finite element model is greater than or equal to the material vaporization temperature. Only when the temperature of the surface node is greater than or equal to the material vaporization temperature, and the temperature of the adjacent node of the surface node in the direction of the normal vector of the mesh plane of the finite element model is less than the material vaporization temperature, is it determined that the surface node has generated a qualified marking mark, thereby minimizing the impact of laser marking on the orthodontic function of the appliance.

[0190] Step 206: Determine whether to adjust the laser scanning process parameters of the workpiece to be marked based on the judgment result.

[0191] After the laser has finished scanning along the entire scanning path, the laser marking effect can be judged based on the marking results of each node along the scanning path. Generally, if more than a certain number of nodes (such as all nodes) on the scanning path produce qualified marking marks, the marking effect is considered good and the marking is qualified. The laser scanning process parameters obtained at this time are the laser scanning process parameters determined in the actual production and processing of the workpiece to be marked. Otherwise, the laser scanning process parameters need to be adjusted and the marking simulation needs to be repeated until the marking is judged to be qualified. The laser scanning process parameters include, but are not limited to, laser spot radius R, heating power flux density P0, and effective power coefficient η.

[0192] In this embodiment, when the proportion of qualified marking surface nodes to all surface nodes in each scanning path is less than a preset threshold, the process returns to step 202 to adjust the laser scanning process parameters until the proportion of qualified marking surface nodes to all surface nodes in each scanning path is greater than or equal to the preset threshold. At this point, the adjusted laser scanning process parameters are obtained.

[0193] In another example, step 202 above further includes configuring the adjustment range of the laser scanning process parameters, and obtaining the laser scanning process parameters within the adjustment range. Accordingly, when it is determined according to step 206 that the laser scanning process parameters of the workpiece to be marked need to be adjusted, the process returns to step 202, and the laser scanning process parameters are adjusted within the adjustment range. That is, in this embodiment, by pre-given the adjustment range of the laser scanning process parameters, when the scanning process parameters need to be adjusted, the laser scanning process parameters can be adjusted traversally within the adjustment range until the optimal laser scanning process parameters for marking are obtained. In this embodiment of the invention, the laser scanning process parameters include, but are not limited to, the laser spot radius R, the heating power flux density P0, and the effective power coefficient η, wherein the adjustment range of the laser spot radius R is 1 to 10 mm, the adjustment range of the heating power flux density P0 is 1 kW to 10 kW, and the adjustment range of the effective power coefficient η is 0 to 1.

[0194] By adjusting the laser marking parameters in this embodiment, the optimal laser scanning process parameters for the current target orthodontic appliance can be obtained. These optimal parameters are then output to the laser marking module during the appliance manufacturing process to complete the laser marking of the target orthodontic appliance, resulting in the final laser marking result. Figure 4 As shown, 1 represents the workpiece to be marked, i.e., the shell-shaped dental appliance; 2 is the marking information block set on the diaphragm; 3 is the diaphragm; and 4 is the dental mold covering the diaphragm, with the marking symbol "123".

[0195] As can be seen, in this embodiment, a finite element model is established for the target orthodontic appliance to be marked. The temperature of each node in the finite element model during the marking simulation is obtained by thermal analysis of the finite element model. Based on the obtained temperature of each node under each scanning path, it is determined whether a marking mark is generated, and then whether the marking is qualified. If the marking is deemed unqualified, the laser scanning process parameters are adjusted and the simulation is repeated until the marking is qualified. Finally, the optimal laser marking process parameters for the workpiece to be marked are obtained. This solves the problem that in the current laser marking process, different personalized orthodontic appliances require continuous manual trials to obtain the optimal laser marking parameters for each appliance, thus improving the production efficiency of the orthodontic appliances.

[0196] Furthermore, it should be understood that the step divisions of the various methods described above are only for clarity. In practice, they can be combined into one step or some steps can be split into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent. Adding insignificant modifications or introducing insignificant designs to the algorithm or process, but without changing the core design of the algorithm and process, are also within the scope of protection of this patent.

[0197] Example 3:

[0198] This embodiment relates to a laser marking simulation device, referencing... Figure 5 The laser marking simulation device can be applied to terminals with communication, computing, and data storage capabilities, such as computers, mobile phones, and other electronic devices, and includes:

[0199] The finite element model acquisition module 301 acquires the finite element model including the workpiece to be marked.

[0200] The finite element model acquisition module 301 includes:

[0201] The finite element model construction module is used to construct a three-dimensional spatial geometric model by connecting key points based on the geometric information of the workpiece to be marked, and to perform meshing on it to obtain the finite element model of the workpiece to be marked.

[0202] The finite element calculation model construction module is used to establish finite element heat conduction control equations related to the material properties of the workpiece to be marked for the finite element model, and to determine the heat transfer boundary conditions and initial conditions on which solving the finite element heat conduction control equations depends, so as to obtain the finite element thermal analysis calculation model. The heat transfer boundary is at least selected as the heat flow boundary condition with the laser heat flux density on the boundary of the finite element model.

[0203] In some embodiments, the finite element calculation model construction module determines the heat flow boundary condition with a given heat flux density on the boundary of the finite element model and the temperature boundary condition with a given portion or all of the boundary of the finite element model being at a constant temperature as the heat transfer boundary condition, and determines the laser heat flux density of the heat flow boundary condition as a function related to the laser scanning process parameters, the laser emission position, and the real-time marking position.

[0204] In other embodiments, the finite element calculation model construction module determines the heat flow boundary condition and the convective heat transfer boundary condition considering convective heat transfer on the boundary of the given finite element model as the heat transfer boundary condition, and determines the laser heat flow density of the heat flow boundary condition as a heat flow density function related to the laser scanning process parameters, laser emission position and real-time marking position.

[0205] In some other embodiments, the finite element calculation model construction module determines the heat transfer boundary conditions as a combination of the heat flux boundary conditions, the temperature boundary conditions, and the convective heat transfer boundary conditions, which are given the laser heat flux density on the boundary of the finite element model, the temperature boundary conditions, which are given that some or all of the boundary of the finite element model are at constant temperatures, and the convective heat transfer boundary conditions, which consider convective heat transfer. The laser heat flux density of the heat flux boundary conditions is determined as a heat flux density function related to the laser scanning process parameters, the laser emission position, and the real-time marking position.

[0206] In this embodiment, the laser heat flux density for the heat flux boundary condition is determined as follows:

[0207]

[0208] in, For a given heat flux density value on the heat transfer boundary that meets the aforementioned heat flux boundary conditions, η is the effective power coefficient; P0 is the heating power flux density; R is the laser spot radius; x, y, and z represent the laser emission position; x focus y focus and z focus These represent the coordinates of the real-time marking position.

[0209] The parameter acquisition module 302 is used for laser scanning of process parameters and material information of the workpiece to be marked.

[0210] The position information acquisition module 303 is used to acquire the laser emission position and the real-time marking position information during the marking simulation process.

[0211] The laser emission position refers to the simulated laser emission position, which is related to the marking information to be marked in the information block to be marked. The marking information includes the marking mark to be printed in the information block to be marked and its corresponding positioning mark. The real-time marking position information refers to the real-time position coordinates of the laser reaching the information block to be marked on the film at different times. The laser emission position can be adjusted to a position that meets the marking focus position information according to the marking information. The real-time marking position is also related to the marking information and the position of the information block to be marked. In this embodiment, the laser emission position and the real-time marking position information are obtained in the following way: the scanning path and total length are determined according to the marking information, and the scanning speed is obtained according to the set scanning time; the real-time marking position coordinates of the scan at different times during the scanning time are obtained according to the scanning speed, that is, the total scanning time is preset, and then the scanning speed is calculated according to the scanning path and total length determined by the marking information. The laser emission position and the real-time marking position coordinates of the scan at different times during the scanning time are calculated according to the scanning speed.

[0212] Specifically, when performing a marking simulation on the target orthodontic appliance to be marked, the position information acquisition module 303 acquires the marking information, determines the laser emission position based on the marking information, and then calculates the scanning speed based on the preset total scanning time, the scanning path and total length determined by the marking information, and calculates the laser emission position and real-time marking position coordinates at different times during the scanning time. Based on the obtained real-time marking position information, the marking mark is printed into the marking information block of the target orthodontic appliance to be marked.

[0213] The analysis and processing module 304 is used to obtain the temperature of each node in the finite element model by using thermal analysis of the finite element model based on the acquired material properties of the workpiece to be marked, laser scanning process parameters and corresponding position information.

[0214] In this embodiment of the invention, based on the laser scanning process parameters and material properties of the workpiece to be marked obtained by the parameter acquisition module 302, and the laser emission position and real-time marking position information of the workpiece during the marking simulation obtained by the position information acquisition module 303, the transient temperature field is solved by the iterative method based on the finite element calculation model of the finite element model acquisition module 301, namely the finite element heat conduction control equation, heat transfer boundary conditions and initial conditions, to obtain the transient temperature field of the finite element model of the workpiece to be marked during the marking simulation, thereby obtaining the temperature of each node in the finite element model.

[0215] In this embodiment, the transient temperature field of the workpiece to be marked is obtained by using an iterative method on the finite element model, including:

[0216] Configure an error tolerance; the error tolerance is the condition for the iterative method to stop iteration.

[0217] The acquired material properties of the workpiece to be marked, laser scanning process parameters, and corresponding position information are input into the finite element model. Based on the finite element heat conduction control equation, heat transfer boundary conditions, and initial conditions, the Gauss-Seidel iterative method is used to solve the transient temperature field and calculate the temperature of each node in the model. In this embodiment, the acquired material properties, laser scanning process parameters, laser emission position information obtained at different times, and real-time marking position coordinates are input into the finite element heat conduction control equation, heat transfer boundary conditions, and initial conditions to calculate the temperature of each node in the finite element model.

[0218] The iteration error is calculated, and iteration stops when the iteration error is less than the error tolerance, thus obtaining the temperature of each node in the finite element model. In one example, the iteration error can be the weighted sum of the differences between two iterations for all nodes. That is, when proceeding to the nth iteration, the difference between the temperatures of all nodes obtained in the nth iteration and the corresponding temperatures of all nodes obtained in the (n-1)th iteration is calculated, and the weighted sum of these differences is obtained to obtain the iteration error. Iteration stops when this iteration error is less than the error tolerance. In another example, the iteration error can be the square root of the sum of the squares of the differences between two iterations for all nodes. That is, the difference between the temperatures of all nodes obtained in the nth iteration and the corresponding temperatures of all nodes obtained in the (n-1)th iteration is calculated, the sum of the squares of these temperature differences is taken, and the square root is obtained to obtain the iteration error. Iteration stops when this iteration error is less than the error tolerance.

[0219] Optionally, in this embodiment, the laser marking simulation device further includes:

[0220] The simulation marking module 305 is used to determine the corresponding marking marks based on the temperature of each node under the scanning path, and obtain the laser marking simulation results.

[0221] In this embodiment, the simulation marking module is specifically used for:

[0222] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0223] If the temperature of a certain surface node is greater than the vaporization temperature of the material of the corresponding workpiece to be marked, then the surface node is determined to generate a marking mark.

[0224] Once the laser marking simulation results of the simulation marking module are obtained through finite element thermal analysis, the final marking effect can be visualized and displayed through the corresponding terminal.

[0225] It is not difficult to see that this embodiment is a device embodiment corresponding to the method embodiment, and this embodiment can be implemented in conjunction with the method embodiment. The relevant technical details mentioned in the method embodiment are still valid in this embodiment, and will not be repeated here to reduce repetition. Correspondingly, the relevant technical details mentioned in this embodiment can also be applied to the method embodiment.

[0226] Example 4:

[0227] This embodiment provides a laser marking parameter adjustment device, for reference... Figure 6 The laser marking parameter adjustment device can be applied to terminals with communication, computing, and data storage capabilities, such as computers, mobile phones, and other electronic devices, and includes:

[0228] Finite element model acquisition module 401 is used to acquire a finite element model including the workpiece to be marked;

[0229] Parameter acquisition module 402 is used to acquire laser scanning process parameters and material properties of the workpiece to be marked;

[0230] The position information acquisition module 403 is used to acquire the laser emission position and the real-time marking position information during the laser marking simulation process;

[0231] The analysis and processing module 404 is used to obtain the temperature of each node in the finite element model by using thermal analysis of the finite element model based on the acquired material properties of the workpiece to be marked, laser scanning process parameters and corresponding position information.

[0232] The finite element model acquisition module 401, parameter acquisition module 402, position information acquisition module 112, and analysis and processing module 404 in this embodiment are similar to the corresponding modules in the ninth embodiment, and will not be described in detail here.

[0233] The judgment module 405 is used to determine whether a qualified marking mark is generated based on the temperature of each node under each scanning path.

[0234] In some embodiments, the determination module 405 is specifically used for:

[0235] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece to be marked;

[0236] When the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, the surface node is determined to produce a qualified marking mark.

[0237] In other embodiments, to prevent laser marking from puncturing the diaphragm of the target orthodontist, the judgment module 405 is specifically used to compare the temperature of each surface node under each scanning path with the material vaporization temperature of the corresponding workpiece to be marked.

[0238] If the temperature of a surface node is greater than or equal to the vaporization temperature of the material, and at least one or more other nodes along the normal vector direction of the mesh plane of the finite element model have a temperature lower than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark.

[0239] In some other embodiments, to ensure that the laser marking is applied only to the surface of the diaphragm and to minimize any impact on the corrective effect of the target orthodontic appliance, the judgment module 405 is specifically used for:

[0240] Based on the temperature of each surface node under each scanning path, compare it with the vaporization temperature of the corresponding workpiece material to be marked;

[0241] If the temperature of a certain surface node is greater than or equal to the vaporization temperature of the material of the workpiece to be marked, and the temperature of the adjacent node along the direction of the normal vector of the mesh plane of the finite element model is less than the vaporization temperature of the material, the surface node is determined to produce a qualified marking mark.

[0242] The parameter adjustment module 406 is used to determine whether to adjust the laser scanning process parameters of the workpiece to be marked based on the judgment result.

[0243] In this embodiment, when the proportion of surface nodes that generate qualified marking marks to all surface nodes under each scanning path is less than a preset threshold, the parameter adjustment unit 406 returns to the parameter acquisition module 402 to adjust the laser scanning process parameters until the proportion of surface nodes that generate qualified marking marks to all surface nodes under each scanning path is greater than or equal to the preset threshold, and finally the adjusted laser scanning process parameters are obtained.

[0244] In this embodiment, a finite element model is established for the target orthodontic appliance to be marked. The temperature of each node in the finite element model during the marking simulation is obtained by thermal analysis of the finite element model. Based on the obtained temperature of each node under each scanning path, it is determined whether a marking mark is generated, and then whether the marking is qualified. If the marking is deemed unqualified, the laser scanning process parameters are adjusted and the simulation is repeated until the marking is deemed qualified. Finally, the optimal laser marking process parameters of the workpiece to be marked are obtained. This solves the problem that in the current laser marking process, different personalized orthodontic appliances require continuous manual trials to obtain the optimal laser marking parameters for each appliance, thus improving the production efficiency of the orthodontic appliances.

[0245] In another embodiment, the parameter acquisition module 402 is further configured to configure the adjustment range of the laser scanning process parameters so as to acquire the laser scanning process parameters within the adjustment range. Accordingly, when the parameter adjustment module 406 determines that the laser scanning process parameters of the workpiece to be marked need to be adjusted, it returns to the parameter acquisition module 111 module 402 to adjust the laser scanning process parameters within the adjustment range.

[0246] It is not difficult to see that this embodiment is a device embodiment corresponding to the method embodiment, and this embodiment can be implemented in conjunction with the method embodiment. The relevant technical details mentioned in the method embodiment are still valid in this embodiment, and will not be repeated here to reduce repetition. Correspondingly, the relevant technical details mentioned in this embodiment can also be applied to the method embodiment.

[0247] It is worth mentioning that all modules involved in this embodiment are logical modules. In practical applications, a logical unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. Furthermore, to highlight the innovative aspects of this invention, this embodiment does not introduce units that are not closely related to solving the technical problem proposed by this invention; however, this does not mean that other units are absent from this embodiment.

[0248] Example 5:

[0249] This embodiment also provides an electronic device, referenced... Figure 7 The method includes: at least one processor 501; and a memory 502 communicatively connected to at least one processor 501; wherein the memory 502 stores instructions executable by at least one processor 501, which are executed by at least one processor 501 to enable at least one processor 501 to perform the laser marking parameter adjustment method described in any of the above method embodiments.

[0250] The memory 502 and processor 501 are connected via a bus, which can include any number of interconnecting buses and bridges. The bus connects various circuits of one or more processors 501 and memory 502 together. The bus can also connect various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. A bus interface provides an interface between the bus and the transceiver. The transceiver can be a single element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by processor 501 is transmitted over a wireless medium via an antenna, which further receives data and transmits it to processor 501.

[0251] Processor 501 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory 502 can be used to store data used by processor 501 during operation.

[0252] Embodiments of the present invention also provide a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the above-described method embodiments.

[0253] That is, those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0254] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing this application, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of this application.

Claims

1. A laser marking simulation method, characterized in that, The method includes: A finite element model of the workpiece to be marked is obtained. The workpiece to be marked includes a dental mold and a diaphragm covering the dental mold. The laser marking is performed on the surface of the diaphragm. Obtain the laser scanning process parameters and the material information of the workpiece to be marked; Obtain the laser emission position and real-time marking position information during the laser marking simulation process; Based on the acquired material information, laser scanning process parameters, and position information, the transient temperature of each node in the finite element model is obtained through thermal analysis using the finite element model. Based on the transient temperature of each surface node under each scanning path, it is compared with the corresponding vaporization temperature of the membrane material; If the transient temperature of a surface node is greater than or equal to the vaporization temperature of the material, and at least one of the other nodes along the normal vector direction of the mesh plane of the finite element model has a transient temperature less than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark.

2. The laser marking simulation method as described in claim 1, characterized in that, The process of obtaining the finite element model of the workpiece to be marked includes: Based on the geometric information of the workpiece to be marked, a three-dimensional spatial geometric model is constructed by connecting key points, and then meshed to obtain the finite element model of the workpiece to be marked. A finite element heat conduction control equation related to the material information of the workpiece to be marked is established for the finite element model, and the heat transfer boundary conditions and initial conditions on which solving the finite element heat conduction control equation depends are determined. The heat transfer boundary conditions shall at least be selected as heat flux boundary conditions with a given laser heat flux density on the boundary of the finite element model.

3. The laser marking simulation method as described in claim 2, characterized in that: The determined heat transfer boundary conditions also include temperature boundary conditions and / or convective heat transfer boundary conditions, which give some or all of the boundaries of the finite element model a constant temperature.

4. The laser marking simulation method as described in claim 2 or 3, characterized in that: The laser heat flux density of the heat flux boundary condition is determined as a heat flux density function related to the laser scanning process parameters, laser emission position, and real-time marking position.

5. The laser marking simulation method as described in claim 4, characterized in that, The laser heat flux density of the heat flux boundary condition is as follows: in, For a given heat flux density value on the heat transfer boundary that meets the aforementioned heat flux boundary conditions, η is the effective power coefficient; P0 is the heating power flux density; R is the laser spot radius; x, y, and z represent the laser emission position; x focus y focus and z focus These represent the coordinates of the real-time marking position.

6. The laser marking simulation method according to any one of claims 1-3, characterized in that, The acquisition of laser emission position and real-time marking position information during the laser marking simulation process includes: The scanning path and total length are determined based on the marking information, and the scanning speed is obtained based on the set scanning time. The coordinates of the laser emission position and the real-time marking position of the scan are obtained at different times during the scanning time based on the scanning speed.

7. The laser marking simulation method according to any one of claims 1-3, characterized in that: In the step of obtaining the transient temperature of each node in the finite element model by thermal analysis based on the acquired material information, laser scanning process parameters and position information, the transient temperature field of the workpiece to be marked is obtained by iterative method on the finite element model based on the acquired material information, laser scanning process parameters and position information, thereby obtaining the transient temperature of each node in the finite element model.

8. The laser marking simulation method as described in claim 7, characterized in that, The step of obtaining the transient temperature field of the workpiece to be marked by using an iterative method on the finite element model includes: Configuration error tolerance; The acquired material information, laser scanning process parameters, and position information are input into the finite element model. Based on the finite element heat conduction control equation, heat transfer boundary conditions, and initial conditions, the Gauss-Seidel iteration method is used to solve the transient temperature field and calculate the temperature of each node in the model. The iteration stops when the error between two iterations is less than the error tolerance, and the temperature of each node of the finite element model is obtained.

9. The laser marking simulation method as described in claim 8, characterized in that, In the step of stopping iteration when the error between two iterations is less than the error tolerance, the sum of the squares of the differences between the two iterations of all nodes is calculated, and the square root of the sum is taken as the iteration error between the two iterations. The iteration is stopped when the iteration error is less than the error tolerance.

10. A laser marking simulation device for the method described in any one of claims 1-9, characterized in that, The device includes: The finite element model acquisition module is used to acquire the finite element model of the workpiece to be marked. The workpiece to be marked includes a dental mold and a diaphragm covering the dental mold. The laser marking is to mark the surface of the diaphragm. The parameter acquisition module is used to acquire laser scanning process parameters and material information of the workpiece to be marked; The position information acquisition module is used to acquire the laser emission position and the real-time marking position information of the laser during the laser marking simulation process; The analysis and processing module is used to obtain the transient temperature of each node in the finite element model by using thermal analysis based on the acquired material information, laser scanning process parameters and position information. The simulation marking module is used to compare the transient temperature of each surface node under each scanning path with the vaporization temperature of the corresponding membrane material. If the transient temperature of a surface node is greater than or equal to the vaporization temperature of the material, and at least one of the other nodes along the normal vector direction of the mesh plane of the finite element model has a transient temperature less than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark.

11. A method for adjusting laser marking parameters for laser marking on shell-shaped orthodontic appliances, comprising: The transient temperature of each node under each scanning path is obtained based on the method described in any one of claims 1-9; Determine whether a qualified marking mark is generated based on the transient temperature of each node under each scanning path. Adjust the laser scanning process parameters based on the assessment results. The step of determining whether a qualified marking mark is generated based on the transient temperature of each node under each scanning path includes: Based on the transient temperature of each surface node under each scanning path, it is compared with the vaporization temperature of the corresponding membrane material; If the transient temperature of a surface node is greater than or equal to the vaporization temperature of the material, and at least one of the other nodes along the normal vector direction of the mesh plane of the finite element model where the surface node is located has a transient temperature less than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark.

12. The laser marking parameter adjustment method as described in claim 11, characterized in that, The step of determining that a surface node generates a qualified marking mark when the transient temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, and at least one other node along the normal vector direction of the mesh plane where the finite element model is located has a transient temperature less than the vaporization temperature of the material, further includes: If the transient temperature of a surface node is greater than or equal to the vaporization temperature of the material, and the transient temperature of the adjacent node along the direction of the normal vector of the mesh plane of the finite element model is less than the vaporization temperature of the material, the surface node is determined to generate a qualified marking mark.

13. The laser marking parameter adjustment method as described in any one of claims 11-12, characterized in that, The adjustment of laser scanning process parameters based on the judgment result includes: When the proportion of surface nodes that produce qualified marking marks to all surface nodes under each scanning path is less than a preset threshold, the laser scanning process parameters are adjusted until the proportion of surface nodes that produce qualified marking marks to all surface nodes under each scanning path is greater than or equal to the preset threshold, thus obtaining the adjusted laser scanning process parameters.

14. The laser marking parameter adjustment method as described in claim 13, characterized in that, The method further includes: Configure the adjustment range of the laser scanning process parameters, obtain the laser scanning process parameters within the adjustment range to perform laser marking simulation, and adjust the laser scanning process parameters.

15. A laser marking parameter adjustment device for laser marking of shell-shaped orthodontic appliances, comprising: The finite element model acquisition module is used to acquire the finite element model of the workpiece to be marked. The parameter acquisition module is used to acquire laser scanning process parameters and material information of the workpiece to be marked; The position information acquisition module is used to acquire the laser emission position and the real-time marking position information of the laser during the laser marking simulation process; The analysis and processing module is used to obtain the transient temperature of each node in the finite element model by using thermal analysis based on the acquired material information, laser scanning process parameters and position information. The judgment module is used to determine whether a qualified marking mark is generated based on the transient temperature of each node under each scanning path. The judgment module compares the transient temperature of each surface node under each scanning path with the vaporization temperature of the corresponding membrane material. If the transient temperature of a certain surface node is greater than or equal to the vaporization temperature of the material, and at least one of the other nodes along the normal vector direction of the mesh plane where the finite element model is located has a transient temperature less than the vaporization temperature of the material, then the surface node is determined to have generated a qualified marking mark. The parameter adjustment processing module is used to adjust the laser scanning process parameters based on the judgment results.

16. An electronic device, characterized in that, include: At least one processor; as well as, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, which, when executed by the at least one processor, enables the at least one processor to perform the laser marking simulation method as described in any one of claims 1 to 9 or the laser marking parameter adjustment method as described in any one of claims 11 to 14.

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