WO2023044926A1 - Method and apparatus for generating additive manufacturing model, and computer-readable storage medium - Google Patents
Method and apparatus for generating additive manufacturing model, and computer-readable storage medium Download PDFInfo
- Publication number
- WO2023044926A1 WO2023044926A1 PCT/CN2021/121081 CN2021121081W WO2023044926A1 WO 2023044926 A1 WO2023044926 A1 WO 2023044926A1 CN 2021121081 W CN2021121081 W CN 2021121081W WO 2023044926 A1 WO2023044926 A1 WO 2023044926A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- voxel
- model
- seed point
- seed
- material information
- Prior art date
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 52
- 239000000654 additive Substances 0.000 title claims abstract description 50
- 230000000996 additive effect Effects 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000003860 storage Methods 0.000 title claims abstract description 7
- 239000000463 material Substances 0.000 claims abstract description 238
- 230000006870 function Effects 0.000 claims description 16
- 238000009826 distribution Methods 0.000 abstract description 10
- 238000010586 diagram Methods 0.000 description 9
- 238000012545 processing Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 230000008859 change Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 230000007704 transition Effects 0.000 description 5
- 238000004364 calculation method Methods 0.000 description 4
- 238000010146 3D printing Methods 0.000 description 3
- 125000000205 L-threonino group Chemical group [H]OC(=O)[C@@]([H])(N([H])[*])[C@](C([H])([H])[H])([H])O[H] 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 238000004422 calculation algorithm Methods 0.000 description 3
- 238000003491 array Methods 0.000 description 2
- 238000004590 computer program Methods 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000013598 vector Substances 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 239000012620 biological material Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000011960 computer-aided design Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012806 monitoring device Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/10—Processes of additive manufacturing
Definitions
- Material type material color; material microstructure.
- Voxelization inside the model After the voxelization operation on the surface of the model is completed, a "shell" representing the voxels of the model can be obtained, and then the internal voxelization operation of the model is performed.
- a spatial octree may first be established based on the corresponding 3D model, and the spatial octree is mainly used for intersecting operations of basic voxel patches. Then, for all empty voxels in the model AABB, two rays are fired in axis-aligned directions from their center positions, the two rays are in opposite directions, but the cardinal directions are both axis-aligned.
- the overall gradient speed of the multi-material model with respect to the material can be directly controlled based on the same control parameters.
- the gradient speed can be adjusted directly based on changing the control parameters. For example: when the control parameter becomes larger, the gradual change of the material information becomes slow; or, when the control parameter becomes smaller, the gradual change of the material information becomes rapid.
- control parameter 53 may be implemented as a parameter, which is used to jointly control the gradient of the material type and color.
- the control parameter 53 can be implemented as two parameters, and each parameter in these two parameters is used to control the degree of gradual change of the material type or The gradient of the color.
- the control parameters of the i-th seed point, the coordinates of the i-th seed point and the coordinates of the j-th voxel can jointly affect the component weight w j of the j-th voxel and the material information of the i-th seed point, i . Therefore, the present invention realizes a technical solution for multi-dimensionally controlling multi-material mixing, which can control the multi-material mixing mode of each voxel point more finely.
- the device 700 for generating an additive manufacturing model includes a processor 701, a memory 702, and a computer program stored in the memory 702 and operable on the processor 701.
- the computer program is executed by the processor 801, the above-mentioned A method for generating an additive manufacturing model.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Optics & Photonics (AREA)
Abstract
Disclosed in embodiments of the present invention are a method and apparatus for generating an additive manufacturing model, and a computer-readable storage medium. The method comprises: acquiring a voxel model; receiving input parameters of N seed points, wherein the input parameters of each seed point comprise coordinate information of the seed point and material information of the seed point, and N is a positive integer of at least 2; on the basis of the input parameters of the N seed points, determining material information of each voxel in the voxel model in a weighted manner; and distributing a material for each voxel on the basis of the material information of each voxel. According to the embodiments of the present invention, a model comprising multiple materials can be generated; moreover, the freedom of multi-material design is provided, and freeform multi-material gradient distribution and multi-material discrete distribution are allowed.
Description
本发明涉及增材制造(Additive Manufacturing，AM)技术领域，特别是一种生成增材制造模型的方法、装置及计算机可读存储介质。The present invention relates to the technical field of additive manufacturing (Additive Manufacturing, AM), in particular to a method, device and computer-readable storage medium for generating an additive manufacturing model.
增材制造融合了计算机辅助设计和材料加工与成型技术，以数字模型文件为基础，通过软件与数控***将金属材料、非金属材料以及医用生物材料，按照挤压、烧结、熔融、光固化、喷射等方式逐层堆积，以制造出实体物品。不同于对原材料去除、切削、组装的传统加工模式，增材制造是一种通过材料累加的制造方法，这使得制造过去受到传统制造方式的约束而无法实现的复杂结构件变为可能。Additive manufacturing combines computer-aided design and material processing and molding technology. Based on digital model files, metal materials, non-metal materials and medical biomaterials are processed according to extrusion, sintering, melting, light curing, Spraying and other methods are piled up layer by layer to create physical objects. Different from the traditional processing mode of raw material removal, cutting, and assembly, additive manufacturing is a manufacturing method through material accumulation, which makes it possible to manufacture complex structural parts that were previously restricted by traditional manufacturing methods.
然而，传统的建模软件(比如CAD)只能将单一材料分配给一个体积对象。当创建多材料对象时，需要为每种材料分别创建几何图形，然后将这些几何图形组合在一起，实现繁琐。However, conventional modeling software such as CAD can only assign a single material to a volumetric object. When creating multi-material objects, it is tedious to create geometry for each material separately and then combine those geometries together.
发明内容Contents of the invention
本发明实施方式提出一种生成增材制造模型的方法、装置及计算机可读存储介质。Embodiments of the present invention provide a method, device, and computer-readable storage medium for generating an additive manufacturing model.
一种生成增材制造模型的方法，包括：A method of generating an additive manufacturing model comprising:
获取体素模型；Get the voxel model;
接收N个种子点的输入参数，其中每个种子点的输入参数包含该种子点的坐标信息和该种子点的材料信息，其中N为至少为2的正整数；Receive input parameters of N seed points, wherein the input parameters of each seed point include coordinate information of the seed point and material information of the seed point, wherein N is a positive integer of at least 2;
基于所述N个种子点的输入参数，以加权方式确定所述体素模型中的每个体素的材料信息；Based on the input parameters of the N seed points, determine the material information of each voxel in the voxel model in a weighted manner;
基于所述每个体素的材料信息为所述每个体素分配材料。A material is assigned to each voxel based on the material information for each voxel.
可见，无需为每种材料分别创建几何图形，即可以在体素维度上生成包含多材料的模型，降低了复杂度。It can be seen that a model containing multiple materials can be generated in the voxel dimension without creating geometry for each material separately, reducing the complexity.
在一个实施方式中，包括下列中的一个：In one embodiment, one of the following is included:
所述N个种子点都位于所述体素模型的内部；The N seed points are all located inside the voxel model;
所述N个种子点都位于所述体素模型的外部；The N seed points are all located outside the voxel model;
所述N个种子点中的一部分种子点位于所述体素模型的内部，所述N个种子点中的剩余种子点位于所述体素模型的外部。Some of the N seed points are located inside the voxel model, and the rest of the N seed points are located outside the voxel model.
因此，种子点具有多种实施方式，提高了灵活度。Therefore, the seed point has multiple implementation modes, which improves the flexibility.
在一个实施方式中，所述种子点的材料信息包括下列中的至少一个：In one embodiment, the material information of the seed point includes at least one of the following:
材料类型；材料颜色；材料微结构。Material type; material color; material microstructure.
可见，可以实现多种类型的材料信息，提高了针对材料的控制维度。It can be seen that various types of material information can be realized, and the control dimension for materials is improved.
在一个实施方式中，其中每个种子点的输入参数还包括适配于控制材料信息的渐变程度的控制参数。In one embodiment, the input parameters of each seed point further include control parameters adapted to control the gradient of material information.
因此，通过引入控制参数，可以实现更多自由度的多材料渐变控制。Therefore, by introducing control parameters, multi-material gradient control with more degrees of freedom can be achieved.
在一个实施方式中，所述控制参数为适配于控制所述种子点的全部材料信息的共同控制参数，或所述控制参数为适配于控制所述种子点的各自材料信息的各自控制参数。In one embodiment, the control parameter is a common control parameter adapted to control all material information of the seed point, or the control parameter is an individual control parameter adapted to control individual material information of the seed point .
可见，控制参数可以实施为控制种子点的全部材料信息，从而降低算法实现难度。而且，控制参数可以实施为控制种子点的特定材料信息，从而实现了精细控制。It can be seen that the control parameters can be implemented to control all the material information of the seed points, thereby reducing the difficulty of algorithm implementation. Moreover, the control parameters can be implemented as the specific material information of the control seed point, thus achieving fine control.
在一个实施方式中，所述基于N个种子点的输入参数，以加权方式确定所述体素模型中的每个体素的材料信息包括：In one embodiment, the weighted determination of the material information of each voxel in the voxel model based on the input parameters of the N seed points includes:
计算第i个种子点的高斯函数f
i(x，y，z)，其中：
Calculate the Gaussian function f i (x, y, z) of the i-th seed point, where:
确定所述体素模型中的第j个体素的、第i个种子点的材料信息的组分权重 w
j，i，其中：
Determine the component weight w j, i of the material information of the i-th seed point of the j-th voxel in the voxel model, wherein:
其中exp是以自然常数e为底的指数函数；(vx
j，vy
j，vz
j)是第j个体素的坐标；(hx
i，hy
i，hz
i)是第i个种子点的坐标；σ
i是第i个种子点的控制参数；π是圆周率；(x，y，z)是任意点的坐标；i∈[1，N]；j∈[1，J]；J为体素的总数目。
Where exp is an exponential function with a natural constant e as the base; (vx j , vy j , vz j ) is the coordinate of the jth voxel; (hx i , hy i , hz i ) is the coordinate of the i-th seed point; σ i is the control parameter of the i-th seed point; π is the pi; (x, y, z) is the coordinate of any point; i∈[1,N]; j∈[1,J]; J is the voxel total number.
因此，基于多个种子点的坐标信息、材料信息和控制参数，高效地生成多材料模型。Therefore, a multi-material model is efficiently generated based on coordinate information, material information, and control parameters of multiple seed points.
在一个实施方式中，所述基于所述每个体素的材料信息为所述每个体素分配材料包括下列中的至少一个：In one embodiment, said assigning a material to said each voxel based on said material information of each voxel comprises at least one of the following:
当所述组分权重w
j，i为0时，不为所述第j个体素指定所述第i个种子点的材料信息所指定的材料；
When the component weight wj,i is 0, the material specified by the material information of the i-th seed point is not specified for the j-th voxel;
当所述组分权重w
j，i为1时，为所述第j个体素全部指定所述第i个种子点的材料信息所指定的材料；
When the component weight wj, i is 1, specify the material specified by the material information of the i-th seed point for all the j-th voxels;
当所述组分权重w
j，i处于0和1之间时，为所述第j个体素指定对应于所述组分权重w
j，i的、所述第i个种子点的材料信息所指定的材料。
When the component weight w j, i is between 0 and 1, assign the jth voxel corresponding to the component weight w j, i , the material information of the ith seed point specified material.
可见，基于每个体素点处、针对特定种子点的组分权重，可以确定出该体素点的混合组分，以实现该体素点处的多材料组合。It can be seen that based on the component weight at each voxel point for a specific seed point, the mixed component of the voxel point can be determined to realize the multi-material combination at the voxel point.
一种生成增材制造模型的装置，包括：An apparatus for generating an additive manufacturing model, comprising:
获取模块，用于获取体素模型；An acquisition module, configured to acquire a voxel model;
接收模块，用于接收N个种子点的输入参数，其中每个种子点的输入参数包含该种子点的坐标信息和该种子点的材料信息，其中N为至少为2的正整数；A receiving module, configured to receive input parameters of N seed points, wherein the input parameters of each seed point include coordinate information of the seed point and material information of the seed point, wherein N is a positive integer of at least 2;
确定模块，用于基于所述N个种子点的输入参数，以加权方式确定所述体素模型中的每个体素的材料信息；A determining module, configured to determine the material information of each voxel in the voxel model in a weighted manner based on the input parameters of the N seed points;
分配模块，用于基于所述每个体素的材料信息为所述每个体素分配材料。An assignment module, configured to assign a material to each voxel based on the material information of each voxel.
可见，无需为每种材料分别创建几何图形，即可以在体素维度上生成包含多 材料的模型，降低了复杂度。It can be seen that a model containing multiple materials can be generated in the voxel dimension without creating geometry for each material separately, reducing the complexity.
在一个实施方式中，包括下列中的一个：In one embodiment, one of the following is included:
所述N个种子点都位于所述体素模型的内部；The N seed points are all located inside the voxel model;
所述N个种子点都位于所述体素模型的外部；The N seed points are all located outside the voxel model;
所述N个种子点中的一部分种子点位于所述体素模型的内部，所述N个种子点中的剩余种子点位于所述体素模型的外部。Some of the N seed points are located inside the voxel model, and the rest of the N seed points are located outside the voxel model.
因此，种子点具有多种实施方式，提高了灵活度。Therefore, the seed point has multiple implementation modes, which improves the flexibility.
在一个实施方式中，所述种子点的材料信息包括下列中的至少一个：In one embodiment, the material information of the seed point includes at least one of the following:
材料类型；材料颜色；材料微结构。Material type; material color; material microstructure.
可见，可以实现多种类型的材料信息，提高了针对材料的控制维度。It can be seen that various types of material information can be realized, and the control dimension for materials is improved.
在一个实施方式中，其中每个种子点的输入参数还包括适配于控制材料信息的渐变程度的控制参数。In one embodiment, the input parameters of each seed point further include control parameters adapted to control the gradient of material information.
因此，通过引入控制参数，可以实现更多自由度的多材料渐变控制。Therefore, by introducing control parameters, multi-material gradient control with more degrees of freedom can be achieved.
在一个实施方式中，所述控制参数为适配于控制所述种子点的全部材料信息的共同控制参数，或所述控制参数为适配于控制所述种子点的各自材料信息的各自控制参数。In one embodiment, the control parameter is a common control parameter adapted to control all material information of the seed point, or the control parameter is an individual control parameter adapted to control individual material information of the seed point .
可见，控制参数可以实施为控制种子点的全部材料信息，从而降低算法实现难度。而且，控制参数可以实施为控制种子点的特定材料信息，从而实现了精细控制。It can be seen that the control parameters can be implemented to control all the material information of the seed points, thereby reducing the difficulty of algorithm implementation. Moreover, the control parameters can be implemented as the specific material information of the control seed point, thus achieving fine control.
在一个实施方式中，所述确定模块，用于计算第i个种子点的高斯函数f
i(x，y，z)，其中：
In one embodiment, the determination module is used to calculate the Gaussian function f i (x, y, z) of the i-th seed point, wherein:
确定所述体素模型中的第j个体素的、第i个种子点的材料信息的组分权重w
j，i，其中：
Determine the component weight w j,i of the material information of the i-th seed point of the j-th voxel in the voxel model, wherein:
其中exp是以自然常数e为底的指数函数；(vx
j，vy
j，vz
j)是第j个体素的坐标；(hx
i，hy
i，hz
i)是第i个种子点的坐标；σ
i是第i个种子点的控制参数；π是圆周率；(x，y，z)是任意点的坐标；i∈[1，N]；j∈[1，J]；J为体素的总数目。
Where exp is an exponential function with a natural constant e as the base; (vx j , vy j , vz j ) is the coordinate of the jth voxel; (hx i , hy i , hz i ) is the coordinate of the i-th seed point; σ i is the control parameter of the i-th seed point; π is the pi; (x, y, z) is the coordinate of any point; i∈[1,N]; j∈[1,J]; J is the voxel total number.
因此，基于多个种子点的坐标信息、材料信息和控制参数，高效地生成多材料模型。Therefore, a multi-material model is efficiently generated based on coordinate information, material information, and control parameters of multiple seed points.
在一个实施方式中，所述分配模块，还用于执行下列中的少一个：In one embodiment, the allocation module is further configured to perform at least one of the following:
当所述组分权重w
j，i为0时，不为所述第j个体素指定所述第i个种子点的材料信息所指定的材料；
When the component weight wj,i is 0, the material specified by the material information of the i-th seed point is not specified for the j-th voxel;
当所述组分权重w
j，i为1时，为所述第j个体素全部指定所述第i个种子点的材料信息所指定的材料；
When the component weight wj, i is 1, specify the material specified by the material information of the i-th seed point for all the j-th voxels;
当所述组分权重w
j，i处于0和1之间时，为所述第j个体素指定对应于所述组分权重w
j，i的、所述第i个种子点的材料信息所指定的材料。
When the component weight w j, i is between 0 and 1, assign the jth voxel corresponding to the component weight w j, i , the material information of the ith seed point specified material.
可见，基于每个体素点处、针对特定种子点的组分权重，可以确定出该体素点的混合组分，以实现该体素点处的多材料组合。It can be seen that based on the component weight at each voxel point for a specific seed point, the mixed component of the voxel point can be determined to realize the multi-material combination at the voxel point.
一种生成增材制造模型的装置，包括处理器和存储器；An apparatus for generating an additive manufacturing model, comprising a processor and a memory;
所述存储器中存储有可被所述处理器执行的应用程序，用于使得所述处理器执行如上任一项所述的生成增材制造模型的方法。An application program executable by the processor is stored in the memory, which is used to make the processor execute the method for generating an additive manufacturing model as described in any one of the above items.
一种计算机可读存储介质，其中存储有计算机可读指令，该计算机可读指令用于执行如上任一项所述的生成增材制造模型的方法。A computer-readable storage medium, in which computer-readable instructions are stored, and the computer-readable instructions are used to execute the method for generating an additive manufacturing model as described in any one of the above.
下面将通过参照附图详细描述本发明的优选实施例，使本领域的普通技术人员更清楚本发明的上述及其它特征和优点，附图中：Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so that those of ordinary skill in the art will be more aware of the above-mentioned and other features and advantages of the present invention. In the accompanying drawings:
图1是根据本发明实施方式的生成增材制造模型的方法的流程图。FIG. 1 is a flowchart of a method for generating an additive manufacturing model according to an embodiment of the present invention.
图2是根据本发明实施方式基于多材料体素模型的增材制造过程的示意图。2 is a schematic diagram of an additive manufacturing process based on a multi-material voxel model according to an embodiment of the present invention.
图3是根据本发明实施方式的种子点的示意图。Fig. 3 is a schematic diagram of a seed point according to an embodiment of the present invention.
图4是根据本发明实施方式的离散模式和梯度模式中多材料分配的对比图。Figure 4 is a graph comparing multi-material distribution in discrete mode and gradient mode according to an embodiment of the present invention.
图5是根据本发明实施方式的生成增材制造模型的方法的示范性流程图。FIG. 5 is an exemplary flowchart of a method for generating an additive manufacturing model according to an embodiment of the present invention.
图6是根据本发明实施方式的生成增材制造模型的装置的结构图。Fig. 6 is a structural diagram of an apparatus for generating an additive manufacturing model according to an embodiment of the present invention.
图7是根据本发明实施方式的具有处理器-存储器架构的、生成增材制造模型的装置的结构图。FIG. 7 is a structural diagram of an apparatus for generating an additive manufacturing model with a processor-memory architecture according to an embodiment of the present invention.
其中，附图标记如下：Wherein, the reference signs are as follows:
为使本发明的目的、技术方案和优点更加清楚，以下举实施例对本发明进一步详细说明。In order to make the purpose, technical solution and advantages of the present invention clearer, the following examples are given to further describe the present invention in detail.
为了描述上的简洁和直观，下文通过描述若干代表性的实施方式来对本发明的方案进行阐述。实施方式中大量的细节仅用于帮助理解本发明的方案。但 是很明显，本发明的技术方案实现时可以不局限于这些细节。为了避免不必要地模糊了本发明的方案，一些实施方式没有进行细致地描述，而是仅给出了框架。下文中，“包括”是指“包括但不限于”，“根据……”是指“至少根据……，但不限于仅根据……”。由于汉语的语言习惯，下文中没有特别指出一个成分的数量时，意味着该成分可以是一个也可以是多个，或可理解为至少一个。For the sake of brevity and intuition in description, the solution of the present invention is described below by describing several representative implementation manners. Numerous details in the embodiments are only used to help the understanding of the solutions of the present invention. But obviously, the technical solution of the present invention may not be limited to these details when implemented. In order to avoid unnecessarily obscuring the solution of the present invention, some embodiments are not described in detail, but only a framework is given. Hereinafter, "including" means "including but not limited to", and "according to..." means "at least according to, but not limited to only based on...". Due to the language habits of Chinese, when the quantity of a component is not specifically indicated below, it means that the component can be one or more, or can be understood as at least one.
本发明实施方式提出了一种生成适用于增材制造(比如3D打印)过程的模型的技术方案。The embodiment of the present invention proposes a technical solution for generating a model suitable for additive manufacturing (such as 3D printing) process.
图1是根据本发明实施方式的生成增材制造模型的方法的流程图。FIG. 1 is a flowchart of a method for generating an additive manufacturing model according to an embodiment of the present invention.
如图1所述，该方法100包括：As shown in Figure 1, the method 100 includes:
步骤101：获取体素模型(voxel model)。Step 101: Obtain a voxel model.
在这里，获取需要被增材制造的对象(通常为三维物体)的体素模型。体素模型是采用大量规则体素(如立方体)的有序组合来表示三维物体的模型。与作为2D图像的最小可识别元素的像素类似，体素是3D体积模型中最小的体积元素。体素模型通过对空间网格上体素占用的详尽列举来表示3D物体。使用体素模型进行多材料增材制造的优势在于：可以为每个体素分配特定的材料属性，例如材料类型、材料颜色和材料微结构，等等。Here, a voxel model of an object (usually a three-dimensional object) to be additively manufactured is obtained. A voxel model is a model that uses an ordered combination of a large number of regular voxels (such as cubes) to represent a three-dimensional object. Similar to a pixel which is the smallest identifiable element of a 2D image, a voxel is the smallest volumetric element in a 3D volumetric model. Voxel models represent 3D objects by an exhaustive enumeration of voxel occupancy on a spatial grid. The advantage of using voxel models for multi-material additive manufacturing is that each voxel can be assigned specific material properties, such as material type, material color, and material microstructure, among others.
在一个实施方式中，可以从建模软件(比如CAD)直接获取被增材制造的对象的体素模型。In one embodiment, the voxel model of the additively manufactured object can be obtained directly from modeling software, such as CAD.
在一个实施方式中，可以从建模软件(比如CAD)获取被增材制造的对象的表面模型(surface model)，再将该表面模型体素化(voxelization)为对象的体素模型。In one embodiment, a surface model (surface model) of the object to be additively manufactured may be obtained from modeling software (such as CAD), and then the surface model is voxelized (voxelized) into a voxel model of the object.
体素化是将对象的几何形式表示转换成最接近该对象的体素表示形式，产生体数据集，其不仅包含模型的表面信息，而且能描述模型的内部属性。表示模型的空间体素跟表示图像的二维像素比较相似，不过从二维的点扩展到三维的立方体单元，而且基于体素的三维模型有诸多应用。Voxelization is to convert the geometric form representation of an object into the voxel representation closest to the object, and generate a volume data set, which not only contains the surface information of the model, but also can describe the internal properties of the model. The spatial voxels that represent models are similar to the two-dimensional pixels that represent images, but they extend from two-dimensional points to three-dimensional cube units, and there are many applications for voxel-based three-dimensional models.
在一个实施方式中：首先设定模型体素化的分辨率，假设为M*M*M； 之后操作主要包括两部分：In one embodiment: first set the resolution of the voxelization of the model, assuming it is M*M*M; then the operation mainly includes two parts:
(1)、对模型表面的体素化：首先计算出模型的AABB包围盒，然后根据空间分辨率对包围盒进行划分，得到每个大小为(X/M)*(Y/M)*(Z/M)空间像素列表。然后，对构成3D模型的多边形或三角形列表进行遍历，得到这些基本体元所对就应的包围盒，再由AABB求交运算得到这些基本体元所能影响到的体素单元，将这些体素单元作为待判断的基本对象。为了做进一步的精确判定，使用三角形与AABB包围盒的求交算法确定这些基本体元所能影响到最终体素，并将这些体素标记为非空，这样就完成了对3D模型表面的体素化操作。(1) Voxelization of the model surface: first calculate the AABB bounding box of the model, and then divide the bounding box according to the spatial resolution, and obtain each size as (X/M)*(Y/M)*( Z/M) space pixel list. Then, traverse the list of polygons or triangles constituting the 3D model to obtain the bounding boxes corresponding to these basic voxels, and then use the AABB intersection operation to obtain the voxel units that these basic voxels can affect, and combine these voxels The element unit is used as the basic object to be judged. In order to make a further accurate judgment, use the intersection algorithm of the triangle and the AABB bounding box to determine that these basic voxels can affect the final voxels, and mark these voxels as non-empty, thus completing the volume on the surface of the 3D model prime operation.
(2)、对模型内部的体素化：对模型表面体素化的操作完成后，即可得到对模型体素表示的一个“外壳”，接下来执行模型的内部体素化操作。在这里，可以首先基于对应的3D模型建立空间八叉树，该空间八叉树主要用于进行基本体元面片的求交操作。然后对模型AABB中的所有空体素，从其中心位置以轴对齐方向来发射两条射线，这两条射线的方向相反，但基本方向都是轴对齐的。对于这两条的射线利用空间模型的八叉树来得到其与3D模型的相交位置，并得到相交点的法向量及到相交点的距离，然后根据这两点法向量之间的关系，判断得到当前体素是在3D模型的内部或是在3D模型的外部。将这样的操作施加于每一个空的体素之后，就可以完成对3D模型内部的体素化操作。(2) Voxelization inside the model: After the voxelization operation on the surface of the model is completed, a "shell" representing the voxels of the model can be obtained, and then the internal voxelization operation of the model is performed. Here, a spatial octree may first be established based on the corresponding 3D model, and the spatial octree is mainly used for intersecting operations of basic voxel patches. Then, for all empty voxels in the model AABB, two rays are fired in axis-aligned directions from their center positions, the two rays are in opposite directions, but the cardinal directions are both axis-aligned. For these two rays, use the octree of the space model to obtain the intersection position with the 3D model, and obtain the normal vector of the intersection point and the distance to the intersection point, and then judge according to the relationship between the normal vectors of these two points Get whether the current voxel is inside the 3D model or outside the 3D model. After applying such an operation to each empty voxel, the voxelization operation on the interior of the 3D model can be completed.
在另一个实施方式中：首先，网格模型通过有符号距离变换转换为由其有符号距离场定义的隐式模型。理论上，有符号距离场是一个标量函数dist(x，y，z)，定义从任意点(x，y，z)到对象边界的最近距离，其中正值表示该点在对象之外，负值表示该点在对象内部，零表示在对象的边界上。在这里，输入网格几何的符号距离场是在具有预定义分辨率的离散空间网格上计算的。然后，将距离值存储在与空间坐标对齐的3D数组中。其次，通过体素化从隐式模型中提取二元体素模型。对于每个体素，存储一个二进制值，其中True(1)表示存在材料(在对象中)，而False(0)表示不存在材料(对象外)。体素模型存储在一个3D数组中，其中每个元素的值由有符号距离数组中相应元素的值决定，其中负符号距离值和零符号距离值导致真(1)的体素值，正符号距离值导致假(0)的体素 值。In another embodiment: First, the mesh model is transformed into an implicit model defined by its signed distance field by a signed distance transform. In theory, a signed distance field is a scalar function dist(x, y, z) that defines the closest distance from any point (x, y, z) to the object boundary, where positive values indicate that the point is outside the object and negative A value means the point is inside the object, zero means it is on the object's boundaries. Here, the signed distance field of the input grid geometry is computed on a discrete spatial grid with a predefined resolution. Then, store the distance values in a 3D array aligned to the spatial coordinates. Second, a binary voxel model is extracted from the implicit model by voxelization. For each voxel, a binary value is stored, where True (1) indicates the presence of material (in the object), and False (0) indicates the absence of material (outside the object). Voxel models are stored in a 3D array where the value of each element is determined by the value of the corresponding element in the signed distance array, where negative signed distance values and zero signed distance values result in a voxel value of true (1), positive signed Distance values result in false (0) voxel values.
以上示范性描述了将表面模型体素化为体素模型的典型实例，本领域技术人员可以意识到，这种描述仅是示范性的，并不用于限定本发明实施方式的保护范围。The above exemplarily describes a typical example of voxelizing a surface model into a voxel model, and those skilled in the art can appreciate that this description is only exemplary and is not intended to limit the protection scope of the embodiments of the present invention.
步骤102：接收N个种子点的输入参数，其中每个种子点的输入参数包含该种子点的坐标信息和该种子点的材料信息，其中N为至少为2的正整数。Step 102: Receive input parameters of N seed points, wherein the input parameters of each seed point include the coordinate information of the seed point and the material information of the seed point, where N is a positive integer of at least 2.
在本发明实施方式中，用户可以使用种子点来决定在何处分配特定材料。在一个实施方式中，N个种子点都位于体素模型的内部。在一个实施方式中，N个种子点都位于体素模型的外部。在一个实施方式中，N个种子点中的一部分种子点位于体素模型的内部，N个种子点中的剩余种子点位于体素模型的外部。In an embodiment of the invention, a user may use a seed point to decide where to dispense a particular material. In one embodiment, the N seed points are all located inside the voxel model. In one embodiment, the N seed points are all located outside the voxel model. In one embodiment, some of the N seed points are located inside the voxel model, and the rest of the N seed points are located outside the voxel model.
在一个实施方式中，每个种子点的输入参数还包括适配于控制材料信息的渐变程度的控制参数。其中，各个种子点的控制参数可以相同，也可以不同。In one embodiment, the input parameters of each seed point further include control parameters adapted to control the gradient of material information. Wherein, the control parameters of each seed point may be the same or different.
种子点的输入参数定义为用户为种子点所输入的数据集。比如，数据集可以包括：种子点的3D空间坐标、分配给种子点的材料信息(例如材料类型、材料颜色、材料微结构)以及适配于控制材料信息的渐变程度的控制参数。The input parameter of the seed point is defined as the dataset input by the user for the seed point. For example, the data set may include: 3D spatial coordinates of the seed points, material information assigned to the seed points (such as material type, material color, material microstructure), and control parameters adapted to control the degree of gradient of the material information.
在一个实施方式中，用户可以通过触发(比如单击)建模场景中源模型内部或外部的任意位置或直接输入精确的3D空间坐标并输入分配给正在创建的种子点的材料信息和控制参数来创建种子点。In one embodiment, the user can model the scene by triggering (such as clicking) any position inside or outside the source model or directly entering the precise 3D space coordinates and entering the material information and control parameters assigned to the seed point being created to create seed points.
在上述方法100中，进一步地：当N为1时，则生成单种材料模型。In the above method 100, further: when N is 1, a single material model is generated.
图3是根据本发明实施方式的种子点的示意图。Fig. 3 is a schematic diagram of a seed point according to an embodiment of the present invention.
由图3可见，在对象的模型30上(比如，表面模型或体素模型)上，设置有5个种子点，分别为种子点31、种子点32、种子点33、种子点34和种子点35。其中，种子点33位于模型30的外部；种子点31、种子点32、种子点34和种子点35都位于模型30中(表面或内部)。针对种子点31、种子点32、种子点33、种子点34和种子点35中的每一个种子点，用户分别输入该种子点的输入参数50。由于种子点的数目为5个，用户需要输入5个输入参数50。It can be seen from Fig. 3 that on the model 30 of the object (for example, a surface model or a voxel model), five seed points are set, which are respectively a seed point 31, a seed point 32, a seed point 33, a seed point 34 and a seed point 35. Among them, the seed point 33 is located outside the model 30; the seed point 31, the seed point 32, the seed point 34 and the seed point 35 are all located in the model 30 (surface or interior). For each of the seed points 31 , 32 , 33 , 34 and 35 , the user inputs an input parameter 50 for the seed point. Since the number of seed points is 5, the user needs to input 5 input parameters 50 .
每个输入参数50都包括坐标信息51、材料信息52和控制参数53。其中，坐标信息51中描述种子点的坐标；材料信息52描述种子点的材料类型、颜色或微结构中的至少一种；控制参数53则适配于控制该种子点材料信息的渐变程度。Each input parameter 50 includes coordinate information 51 , material information 52 and control parameters 53 . Among them, the coordinate information 51 describes the coordinates of the seed point; the material information 52 describes at least one of the material type, color or microstructure of the seed point; the control parameter 53 is adapted to control the gradual change degree of the material information of the seed point.
当各个种子点的控制参数都相同时，基于该相同的控制参数可以直接控制多材料模型关于材料的整体渐变速度。比如，当各个种子点的控制参数都相同时，可以直接基于改变该控制参数以调整渐变速度。比如：可以当控制参数变大时，材料信息的渐变变得缓慢；或，当控制参数变小时，材料信息的渐变变得迅速。When the control parameters of each seed point are the same, the overall gradient speed of the multi-material model with respect to the material can be directly controlled based on the same control parameters. For example, when the control parameters of each seed point are the same, the gradient speed can be adjusted directly based on changing the control parameters. For example: when the control parameter becomes larger, the gradual change of the material information becomes slow; or, when the control parameter becomes smaller, the gradual change of the material information becomes rapid.
在一个实施方式中，控制参数53为适配于控制种子点的全部材料信息的共同控制参数，或控制参数为适配于控制种子点的各自材料信息的各自控制参数。In one embodiment, the control parameter 53 is a common control parameter adapted to all material information of the control seed points, or the control parameters are individual control parameters adapted to the respective material information of the control seed points.
比如，当材料信息52中描述了种子点的材料类型和颜色时，控制参数53可以实施为一个参数，该参数用于共同控制材料类型和颜色的渐变程度。可选地，当材料信息52中描述了种子点的材料类型和颜色时，控制参数53可以实施为两个参数，这两个参数中的每个参数，分别用于控制材料类型的渐变程度或颜色的渐变程度。For example, when the material type and color of the seed point are described in the material information 52, the control parameter 53 may be implemented as a parameter, which is used to jointly control the gradient of the material type and color. Optionally, when the material type and color of the seed point are described in the material information 52, the control parameter 53 can be implemented as two parameters, and each parameter in these two parameters is used to control the degree of gradual change of the material type or The gradient of the color.
步骤103：基于N个种子点的输入参数，以加权方式确定体素模型中的每个体素的材料信息。Step 103: Based on the input parameters of the N seed points, determine the material information of each voxel in the voxel model in a weighted manner.
在这里，步骤103具体包括：Here, step 103 specifically includes:
(1)、计算第i个种子点的高斯函数f
i(x，y，z)，其中：
(1), calculate the Gaussian function f i (x, y, z) of the i-th seed point, where:
(2)、确定体素模型中的第j个体素的、第i个种子点的材料信息的组分权重w
j，i，其中：
(2) Determine the component weight w j, i of the jth voxel in the voxel model and the material information of the ith seed point, wherein:
其中exp是以自然常数e为底的指数函数；(vx
j，vy
j，vz
j)是第j个体素的坐 标；(hx
i，hy
i，hz
i)是第i个种子点的坐标；σ
i是第i个种子点的控制参数；π是圆周率；(x，y，z)是任意点的坐标；i∈[1，N]；j∈[1，J]；J为体素的总数目。
Where exp is an exponential function with a natural constant e as the base; (vx j , vy j , vz j ) is the coordinate of the jth voxel; (hx i , hy i , hz i ) is the coordinate of the i-th seed point; σ i is the control parameter of the i-th seed point; π is the pi; (x, y, z) is the coordinate of any point; i∈[1,N]; j∈[1,J]; J is the voxel total number.
因此，可以计算出体素模型中的每个体素处的、关于每个种子点的材料信息的组分权重。Therefore, the component weights of the material information about each seed point at each voxel in the voxel model can be calculated.
可见，第i个种子点的控制参数、第i个种子点的坐标以及第j个体素的坐标，可以共同影响第j个体素的、第i个种子点的材料信息的组分权重w
j，i。因此，本发明实现了一种多维度地控制多材料混合的技术方案，可以更精细地控制每个体素点的多材料混合方式。
It can be seen that the control parameters of the i-th seed point, the coordinates of the i-th seed point and the coordinates of the j-th voxel can jointly affect the component weight w j of the j-th voxel and the material information of the i-th seed point, i . Therefore, the present invention realizes a technical solution for multi-dimensionally controlling multi-material mixing, which can control the multi-material mixing mode of each voxel point more finely.
步骤104：基于每个体素的材料信息为每个体素分配材料。Step 104: Assign a material to each voxel based on the material information of each voxel.
在这里，基于如下原则为每个体素分配材料：Here, materials are assigned to each voxel based on the following principles:
(1)、当组分权重w
j，i为0时，不为第j个体素分配第i个种子点的材料信息所指定的材料。
(1) When the component weight w j, i is 0, the material specified by the material information of the i-th seed point is not assigned to the j-th voxel.
(2)、当组分权重w
j，i为1时，为第j个体素全部分配第i个种子点的材料信息所指定的材料。
(2) When the component weight w j,i is 1, assign the material specified by the material information of the i-th seed point to all j-th voxels.
(3)、当组分权重w
j，i处于0和1之间时，为第j个体素分配对应于组分权重w
j，i的、第i个种子点的材料信息所指定的材料。
(3) When the component weight w j,i is between 0 and 1, assign the material specified by the material information of the i-th seed point corresponding to the component weight w j,i to the j-th voxel.
也就是，特定材料在体素上的组分权重为0表示不应在该体素处放置该特定材料，而组分权重为1表示该体素仅被该特定材料占据。0到1之间的组分权重值，表示该体素由具有特定权重的多种材料组成。而且，每个体素处所有材料的合成权重之和等于1，即
That is, a composition weight of 0 for a particular material on a voxel means that that particular material should not be placed at that voxel, while a composition weight of 1 means that that voxel is only occupied by that particular material. A component weight value between 0 and 1 indicating that this voxel is composed of multiple materials with specific weights. Moreover, the sum of the composite weights of all materials at each voxel is equal to 1, that is,
比如，假定有3个种子点，分别为种子点1、种子点2和种子点3，其中种子点1的材料信息为材料A、种子点2的材料信息为材料B，种子点3的材料信息为材料C。基于上述计算方式，可以计算出体素模型中的每个体素处的、关于每个种子点的材料信息的组分权重。针对体素T1，假定种子点1的组分权重为0.2、种子点2的组分权重为0.5、种子点3的组分权重为0.3。那么，可以 在体素T1处，分配多材料，其中该多材料的组分为：20％的材料A；50％的材料B；30％的材料C。For example, suppose there are 3 seed points, namely seed point 1, seed point 2 and seed point 3, where the material information of seed point 1 is material A, the material information of seed point 2 is material B, and the material information of seed point 3 is For material C. Based on the above calculation method, the component weight of the material information of each seed point at each voxel in the voxel model can be calculated. For voxel T1, it is assumed that the component weight of seed point 1 is 0.2, the component weight of seed point 2 is 0.5, and the component weight of seed point 3 is 0.3. Then, at voxel T1, a multi-material can be dispensed, wherein the composition of the multi-material is: 20% material A; 50% material B; 30% material C.
再比如，假定有3个种子点，分别为种子点1、种子点2和种子点3，其中种子点1的材料信息为具有颜色A的材料T(如塑料)、种子点2的材料信息为具有颜色B的材料T，种子点3的材料信息为具有颜色C的材料T。基于上述计算方式，可以计算出体素模型中的每个体素处的、关于每个种子点的材料信息的组分权重。针对体素T1，假定种子点1的组分权重为0.2、种子点2的组分权重为0.5、种子点3的组分权重为0.3。那么，可以在体素T1处，分配多材料，其中该多材料的组分为：20％的具有颜色A的材料T；50％的颜色的具有颜色B的材料T；30％的具有颜色C的材料T。For another example, assume that there are 3 seed points, namely seed point 1, seed point 2 and seed point 3, wherein the material information of seed point 1 is material T (such as plastic) with color A, and the material information of seed point 2 is For material T with color B, the material information of seed point 3 is material T with color C. Based on the above calculation method, the component weight of the material information of each seed point at each voxel in the voxel model can be calculated. For voxel T1, it is assumed that the component weight of seed point 1 is 0.2, the component weight of seed point 2 is 0.5, and the component weight of seed point 3 is 0.3. Then, at voxel T1, a multimaterial can be assigned, wherein the composition of the multimaterial is: 20% of material T with color A; 50% of material T with color B; 30% of material T with color C The material T.
本发明实施方式中，还实现了多材料分布离散模式和多材料分布渐变模式。In the embodiment of the present invention, a multi-material distribution discrete mode and a multi-material distribution gradual change mode are also realized.
在多材料分布离散模式中：特定体素的最终材料分配结果是：该特定体素处的材料即为具有最大组合权重的材料。即hm
i，其中w
j，i＝max w
j，k，对于i∈[1，N]。在特定体素处，将具有最大组分权重的材料的相应组合权重设置为1，而其余材料的权重值设置为0。换句话说，将在该特定体素处，全部分配该具有最大组分权重的材料，而不分配其它材料。
In the multi-material distribution discrete mode: the final material allocation result of a specific voxel is: the material at this specific voxel is the material with the maximum combined weight. That is hm i , where w j,i =max w j,k , for i∈[1,N]. At a specific voxel, the corresponding combined weight of the material with the largest component weight is set to 1, while the weight value of the remaining materials is set to 0. In other words, at that particular voxel, the material with the largest component weight will be assigned in its entirety, and no other materials will be assigned.
在多材料分布渐变模式中：体素内每种材料的材料组成权重值可以在0到1之间。在这种模式下可以实现不同材料之间的自然梯度过渡。用户可以设置阈值参数w
thres以消除低组分权重的材料。根据材料成分的组分权重计算，对于小于阈值的组分权重值，即w
j，i＜w
thres，对应的高斯函数值f
i(vx
j，vy
j，vz
j)将设置为0。剔除所有较小的组分权重后，将再次进行组分权重计算。其中：当w
thres＝0时，不进行阈值处理。
In multi-material distribution gradient mode: The material composition weight value for each material within a voxel can be between 0 and 1. Natural gradient transitions between different materials can be achieved in this mode. The user can set the threshold parameter w thres to eliminate materials with low component weights. According to the component weight calculation of the material component, for the component weight value less than the threshold value, ie w j, i < w thres , the corresponding Gaussian function value f i (vx j , vy j , vz j ) will be set to 0. After removing all smaller component weights, the component weight calculations are performed again. Where: when w thres =0, no threshold processing is performed.
图4是根据本发明实施方式的离散模式和梯度模式中多材料分配的对比图。Figure 4 is a graph comparing multi-material distribution in discrete mode and gradient mode according to an embodiment of the present invention.
在图4中，模型421和模型422为多材料分布渐变模式中的展示模型，模型411为多材料分布离散模式中的展示模型，其中均采用上述高斯函数方式确定出各自模型。其中：生成模型421时所采用的控制参数小于生成模型422时 所采用的控制参数。可见，模型411具有离散的转变效果。模型421和模型422具有渐变的转变效果，而且模型421相对于模型422的渐变更快。In FIG. 4 , model 421 and model 422 are display models in the multi-material distribution gradient mode, and model 411 is a display model in the multi-material distribution discrete mode, and the above-mentioned Gaussian function method is used to determine the respective models. Wherein: the control parameter adopted when generating model 421 is smaller than the control parameter adopted when generating model 422. It can be seen that model 411 has discrete transition effects. Model 421 and model 422 have a gradual transition effect, and model 421 has a faster gradient than model 422 .
模型411的第一横截面412、模型421的第一横截面422和模型431的第一横截面432，都具有相同的截面高度h1。可见，第一横截面412具有离散的转变效果。第一横截面422和第一横截面432具有渐变效果，而且第一横截面422相对于第一横截面432的渐变更快。The first cross section 412 of the model 411 , the first cross section 422 of the model 421 and the first cross section 432 of the model 431 all have the same section height h1. It can be seen that the first cross-section 412 has a discrete transition effect. The first cross section 422 and the first cross section 432 have a gradient effect, and the gradient of the first cross section 422 is faster than that of the first cross section 432 .
模型411的第二横截面413、模型421的第二横截面423和模型431的第二横截面433，具有相同的截面高度h2，其中h1不等于h2。可见，第二横截面413具有离散的转变效果。第二横截面423和第二横截面433具有渐变效果，而且第二横截面423相对于第二横截面433的渐变更快。The second cross section 413 of the model 411 , the second cross section 423 of the model 421 and the second cross section 433 of the model 431 have the same section height h2, wherein h1 is not equal to h2. It can be seen that the second cross section 413 has a discrete transition effect. The second cross section 423 and the second cross section 433 have a gradation effect, and the gradation of the second cross section 423 is faster than that of the second cross section 433 .
图5是根据本发明实施方式的生成增材制造模型方法的示范性流程图。FIG. 5 is an exemplary flowchart of a method for generating an additive manufacturing model according to an embodiment of the present invention.
如图5所示，该方法包括：As shown in Figure 5, the method includes:
步骤501：创建或输入用于多材料分配的源模型。Step 501: Create or import a source model for multi-material allocation.
步骤502：判断该源模型是否是体素模型，如果是(对应于图5中的“Y”分支)，则执行步骤504及其后续步骤，如果不是(对应于图5中的“N”分支)，则执行步骤503及其后续步骤。Step 502: judge whether the source model is a voxel model, if yes (corresponding to "Y" branch in Fig. 5), then execute step 504 and its subsequent steps, if not (corresponding to "N" branch in Fig. 5 ), then execute step 503 and its subsequent steps.
步骤503：将该源模型转换为体素模型。Step 503: Convert the source model into a voxel model.
步骤504：接收用户输入以创建种子点。Step 504: Receive user input to create seed points.
步骤505：利用种子点计算体素模型内的每个体素的材料信息。Step 505: Using the seed point to calculate the material information of each voxel in the voxel model.
步骤506：按照每个体素的材料信息，为该体素分配材料，以形成多材料的增材制造模型。Step 506: According to the material information of each voxel, assign materials to the voxel to form a multi-material additive manufacturing model.
步骤507：渲染和展示该多材料的增材制造模型。Step 507: rendering and displaying the multi-material additive manufacturing model.
步骤508：判断是否修改该多材料的增材制造模型，如果是(对应于图5中的“Y”分支)，则执行步骤505及其后续步骤，如果不是(对应于图5中的“N”分支)，则执行步骤509。Step 508: Determine whether to modify the multi-material additive manufacturing model, if yes (corresponding to the "Y" branch in Figure 5), then execute step 505 and its subsequent steps, if not (corresponding to the "N" branch in Figure 5 " branch), then execute step 509.
步骤509：输出该多材料的增材制造模型，以用于增材制造。Step 509: Output the multi-material additive manufacturing model for additive manufacturing.
图2是根据本发明实施方式基于多材料体素模型的增材制造的示意图。Fig. 2 is a schematic diagram of additive manufacturing based on a multi-material voxel model according to an embodiment of the present invention.
由图2可见，将表面模型体素化为体素模型21，并针对体素模型21中每个体素生成各自的材料信息以生成多材料体素模型22。然后，利用3D打印设备23基于该多材料体素模型22执行3D打印。As can be seen from FIG. 2 , the surface model is voxelized into a voxel model 21 , and respective material information is generated for each voxel in the voxel model 21 to generate a multi-material voxel model 22 . Then, 3D printing is performed based on the multi-material voxel model 22 using a 3D printing device 23 .
图6是根据本发明实施方式的生成增材制造模型装置的结构图。如图6所示，生成增材制造模型的装置600包括：Fig. 6 is a structural diagram of an apparatus for generating an additive manufacturing model according to an embodiment of the present invention. As shown in Figure 6, the device 600 for generating the additive manufacturing model includes:
获取模块601，用于获取体素模型；接收模块602，用于接收N个种子点的输入参数，其中每个种子点的输入参数包含种子点的坐标和种子点的材料信息，其中N为至少为2的正整数；确定模块603，用于基于N个种子点的输入参数，以加权方式确定体素模型中的每个体素的材料信息；分配模块604，用于基于每个体素的材料信息为每个体素分配材料。The obtaining module 601 is used to obtain the voxel model; the receiving module 602 is used to receive input parameters of N seed points, wherein the input parameters of each seed point include the coordinates of the seed point and the material information of the seed point, wherein N is at least It is a positive integer of 2; the determination module 603 is used to determine the material information of each voxel in the voxel model in a weighted manner based on the input parameters of N seed points; the allocation module 604 is used to determine the material information based on each voxel Assign materials to each voxel.
在一个实施方式中，包括下列中的一个：N个种子点都位于体素模型的内部；N个种子点都位于体素模型的外部；N个种子点中的一部分种子点位于体素模型的内部，N个种子点中的剩余种子点位于体素模型的外部。In one embodiment, one of the following is included: the N seed points are all located inside the voxel model; the N seed points are all located outside the voxel model; a part of the N seed points are located in the voxel model Inside, the rest of the N seed points are located outside the voxel model.
在一个实施方式中，种子点的材料信息包括下列中的至少一个：材料类型；材料颜色；材料微结构。In one embodiment, the material information of the seed point includes at least one of the following: material type; material color; material microstructure.
在一个实施方式中，其中每个种子点的输入参数还包括适配于控制材料信息的渐变程度的控制参数。In one embodiment, the input parameters of each seed point further include control parameters adapted to control the gradient of material information.
在一个实施方式中，控制参数为适配于控制种子点的全部材料信息的共同控制参数，或控制参数为适配于控制种子点的各自材料信息的各自控制参数。In one embodiment, the control parameter is a common control parameter adapted to all material information of the control seed points, or the control parameters are individual control parameters adapted to the respective material information of the control seed points.
在一个实施方式中，确定模块(603)，用于计算第i个种子点的高斯函数f
i(x，y，z)，其中：
确定体素模型中的第j个体素的、第i个种子点的材料信息的组分权重w
j，i，其中
其中exp是以自然常数e为底的指数函数；(vx
j，vy
j，vz
j)是第j个体素的坐标；(hx
i，hy
i，hz
i)是第i个种子点的坐标；σ
i是第i个种子点的 控制参数；π是圆周率；(x，y，z)是任意点的坐标；i∈[1，N]；j∈[1，J]；J为体素的总数目。
In one embodiment, the determination module (603) is used to calculate the Gaussian function f i (x, y, z) of the i-th seed point, wherein: Determine the component weight w j,i of the material information of the i-th seed point of the j-th voxel in the voxel model, where Where exp is an exponential function with a natural constant e as the base; (vx j , vy j , vz j ) is the coordinate of the jth voxel; (hx i , hy i , hz i ) is the coordinate of the i-th seed point; σ i is the control parameter of the i-th seed point; π is the pi; (x, y, z) is the coordinate of any point; i∈[1,N]; j∈[1,J]; J is the voxel total number.
在一个实施方式中，分配模块604，用于执行下列中的少一个：当组分权重w
j，i为0时，不为第j个体素分配第i个种子点的材料信息所指定的材料；当组分权重w
j，i为1时，为第j个体素全部分配第i个种子点的材料信息所指定的材料；当组分权重w
j，i处于0和1之间时，为第j个体素分配对应于组分权重w
j，i的、第i个种子点的材料信息所指定的材料。
In one embodiment, the assignment module 604 is configured to perform at least one of the following: when the component weight w j,i is 0, do not assign the material specified by the material information of the i-th seed point to the j-th voxel ; When the component weight w j,i is 1, the material specified by the material information of the i-th seed point is assigned to the j-th voxel; when the component weight w j,i is between 0 and 1, it is The j-th voxel is allocated to the material specified by the material information of the i-th seed point corresponding to the component weight w j,i .
本发明实施方式还提出了一种具有处理器-存储器架构的、变频器的状态监控装置。图7是根据本发明实施方式的具有处理器-存储器架构的、生成增材制造模型的装置的结构图。The embodiment of the present invention also proposes a state monitoring device for a frequency converter with a processor-memory architecture. FIG. 7 is a structural diagram of an apparatus for generating an additive manufacturing model with a processor-memory architecture according to an embodiment of the present invention.
如图7所示，生成增材制造模型的装置700包括处理器701、存储器702及存储在存储器702上并可在处理器701上运行的计算机程序，计算机程序被处理器801执行时实现如上任一种的生成增材制造模型的方法。As shown in FIG. 7 , the device 700 for generating an additive manufacturing model includes a processor 701, a memory 702, and a computer program stored in the memory 702 and operable on the processor 701. When the computer program is executed by the processor 801, the above-mentioned A method for generating an additive manufacturing model.
其中，存储器702具体可以实施为电可擦可编程只读存储器(EEPROM)、快闪存储器(Flash memory)、可编程程序只读存储器(PROM)等多种存储介质。处理器701可以实施为包括一或多个中央处理器或一或多个现场可编程门阵列，其中现场可编程门阵列集成一或多个中央处理器核。具体地，中央处理器或中央处理器核可以实施为CPU或MCU或DSP，等等。Wherein, the memory 702 can be specifically implemented as various storage media such as electrically erasable programmable read-only memory (EEPROM), flash memory (Flash memory), and programmable program read-only memory (PROM). The processor 701 may be implemented to include one or more central processing units or one or more field programmable gate arrays, wherein the field programmable gate arrays integrate one or more central processing unit cores. Specifically, the central processing unit or central processing unit core may be implemented as a CPU or MCU or DSP, and so on.
需要说明的是，上述各流程和各结构图中不是所有的步骤和模块都是必须的，可以根据实际的需要忽略某些步骤或模块。各步骤的执行顺序不是固定的，可以根据需要进行调整。各模块的划分仅仅是为了便于描述采用的功能上的划分，实际实现时，一个模块可以分由多个模块实现，多个模块的功能也可以由同一个模块实现，这些模块可以位于同一个设备中，也可以位于不同的设备中。It should be noted that not all steps and modules in the above-mentioned processes and structure diagrams are necessary, and some steps or modules can be ignored according to actual needs. The execution order of each step is not fixed and can be adjusted as needed. The division of each module is only to facilitate the description of the functional division adopted. In actual implementation, one module can be divided into multiple modules, and the functions of multiple modules can also be realized by the same module. These modules can be located in the same device. , or on a different device.
各实施方式中的硬件模块可以以机械方式或电子方式实现。例如，一个硬件模块可以包括专门设计的永久性电路或逻辑器件(如专用处理器，如FPGA或ASIC)用于完成特定的操作。硬件模块也可以包括由软件临时配置的可编程 逻辑器件或电路(如包括通用处理器或其它可编程处理器)用于执行特定操作。至于具体采用机械方式，或是采用专用的永久性电路，或是采用临时配置的电路(如由软件进行配置)来实现硬件模块，可以根据成本和时间上的考虑来决定。The hardware modules in the various embodiments may be implemented mechanically or electronically. For example, a hardware module may include specially designed permanent circuits or logic devices (such as special-purpose processors, such as FPGAs or ASICs) to perform specific operations. Hardware modules may also include programmable logic devices or circuits (including, for example, general-purpose processors or other programmable processors) temporarily configured by software to perform particular operations. As for implementing the hardware module in a mechanical way, using a dedicated permanent circuit, or using a temporarily configured circuit (such as configured by software) to realize the hardware module, it can be decided according to cost and time considerations.
以上所述，仅为本发明的较佳实施方式而已，并非用于限定本发明的保护范围。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。The above descriptions are only preferred implementation modes of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.
Claims (16)
- 一种生成增材制造模型的方法(100)，其特征在于，包括：A method (100) of generating an additive manufacturing model, comprising:获取体素模型(101)；Obtain a voxel model (101);接收N个种子点的输入参数，其中每个种子点的输入参数包含该种子点的坐标信息和该种子点的材料信息，其中N为至少为2的正整数(102)；Receive input parameters of N seed points, wherein the input parameters of each seed point include the coordinate information of the seed point and the material information of the seed point, wherein N is a positive integer (102) that is at least 2;基于所述N个种子点的输入参数，以加权方式确定所述体素模型中的每个体素的材料信息(103)；Based on the input parameters of the N seed points, determine the material information of each voxel in the voxel model in a weighted manner (103);基于所述每个体素的材料信息为所述每个体素分配材料(104)。A material is assigned to each voxel based on the material information for each voxel (104).
- 根据权利要求1所述的生成增材制造模型的方法(100)，其特征在于，包括下列中的一个：The method (100) for generating an additive manufacturing model according to claim 1, comprising one of the following:所述N个种子点都位于所述体素模型的内部；The N seed points are all located inside the voxel model;所述N个种子点都位于所述体素模型的外部；The N seed points are all located outside the voxel model;所述N个种子点中的一部分种子点位于所述体素模型的内部，所述N个种子点中的剩余种子点位于所述体素模型的外部。Some of the N seed points are located inside the voxel model, and the rest of the N seed points are located outside the voxel model.
- 根据权利要求1所述的生成增材制造模型的方法(100)，其特征在于，所述种子点的材料信息包括下列中的至少一个：The method (100) for generating an additive manufacturing model according to claim 1, wherein the material information of the seed point includes at least one of the following:材料类型；材料颜色；材料微结构。Material type; material color; material microstructure.
- 根据权利要求1所述的生成增材制造模型的方法(100)，其特征在于，其中每个种子点的输入参数还包括适配于控制材料信息的渐变程度的控制参数。The method (100) for generating an additive manufacturing model according to claim 1, wherein the input parameters of each seed point further include control parameters adapted to control the gradient of material information.
- 根据权利要求4所述的生成增材制造模型的方法(100)，其特征在于，所述控制参数为适配于控制所述种子点的全部材料信息的共同控制参数，或所述控制参数为适配于控制所述种子点的各自材料信息的各自控制参数。The method (100) for generating an additive manufacturing model according to claim 4, wherein the control parameter is a common control parameter adapted to control all material information of the seed point, or the control parameter is Respective control parameters adapted to control the respective material information of said seed points.
- 根据权利要求4所述的生成增材制造模型的方法(100)，其特征在于，所述基于N个种子点的输入参数，以加权方式确定所述体素模型中的每个体素的材料信息(103)包括：The method (100) for generating an additive manufacturing model according to claim 4, wherein the input parameters based on N seed points determine the material information of each voxel in the voxel model in a weighted manner (103) including:计算第i个种子点的高斯函数f i(x，y，z)，其中： Calculate the Gaussian function f i (x, y, z) of the i-th seed point, where:
确定所述体素模型中的第j个体素的、第i个种子点的材料信息的组分权重w j，i，其中： Determine the component weight w j,i of the material information of the i-th seed point of the j-th voxel in the voxel model, wherein:
其中exp是以自然常数e为底的指数函数；(vx j，vy j，vz j)是第j个体素的坐标；(hx i，hy i，hz i)是第i个种子点的坐标；σ i是第i个种子点的控制参数；π是圆周率；(x，y，z)是任意点的坐标；i∈[1，N]；j∈[1，J]；J为体素的总数目。 Where exp is an exponential function with a natural constant e as the base; (vx j , vy j , vz j ) is the coordinate of the jth voxel; (hx i , hy i , hz i ) is the coordinate of the i-th seed point; σ i is the control parameter of the i-th seed point; π is the pi; (x, y, z) is the coordinate of any point; i∈[1,N]; j∈[1,J]; J is the voxel total number. - 根据权利要求6所述的生成增材制造模型的方法(100)，其特征在于，所述基于每个体素的材料信息为所述每个体素分配材料(104)包括下列中的至少一个：The method (100) for generating an additive manufacturing model according to claim 6, wherein the assigning material (104) to each voxel based on the material information of each voxel comprises at least one of the following:当所述组分权重w j，i为0时，不为所述第j个体素分配所述第i个种子点的材料信息所指定的材料； When the component weight wj,i is 0, the material specified by the material information of the i-th seed point is not assigned to the j-th voxel;当所述组分权重w j，i为1时，为所述第j个体素全部分配所述第i个种子点的材料信息所指定的材料； When the component weight wj,i is 1, assign the material specified by the material information of the i-th seed point to all the j-th voxels;当所述组分权重w j，i处于0和1之间时，为所述第j个体素分配对应于所述组分权重w j，i的、所述第i个种子点的材料信息所指定的材料。 When the component weight w j, i is between 0 and 1, assign the jth voxel corresponding to the component weight w j, i , the material information of the ith seed point specified material.
- 一种生成增材制造模型的装置(600)，其特征在于，包括：A device (600) for generating an additive manufacturing model, characterized in that it comprises:获取模块(601)，用于获取体素模型；An acquisition module (601), configured to acquire a voxel model;接收模块(602)，用于接收N个种子点的输入参数，其中每个种子点的输入参数包含该种子点的坐标信息和该种子点的材料信息，其中N为至少为2的正整数；A receiving module (602), configured to receive input parameters of N seed points, wherein the input parameters of each seed point include coordinate information of the seed point and material information of the seed point, wherein N is a positive integer that is at least 2;确定模块(603)，用于基于所述N个种子点的输入参数，以加权方式确定所述体素模型中的每个体素的材料信息；A determination module (603), configured to determine material information of each voxel in the voxel model in a weighted manner based on the input parameters of the N seed points;分配模块(604)，用于基于所述每个体素的材料信息为所述每个体素分配材料。An assignment module (604), configured to assign a material to each voxel based on the material information of each voxel.
- 根据权利要求8所述的生成增材制造模型的装置(600)，其特征在于，包括下列中的一个：The device (600) for generating an additive manufacturing model according to claim 8, characterized in that it comprises one of the following:所述N个种子点都位于所述体素模型的内部；The N seed points are all located inside the voxel model;所述N个种子点都位于所述体素模型的外部；The N seed points are all located outside the voxel model;所述N个种子点中的一部分种子点位于所述体素模型的内部，所述N个种子点中的剩余种子点位于所述体素模型的外部。Some of the N seed points are located inside the voxel model, and the rest of the N seed points are located outside the voxel model.
- 根据权利要求8所述的生成增材制造模型的装置(600)，其特征在于，所述种 子点的材料信息包括下列中的至少一个：The device (600) for generating an additive manufacturing model according to claim 8, wherein the material information of the seed point includes at least one of the following:材料类型；材料颜色；材料微结构。Material type; material color; material microstructure.
- 根据权利要求8所述的生成增材制造模型的装置(600)，其特征在于，其中每个种子点的输入参数还包括适配于控制材料信息的渐变程度的控制参数。The device (600) for generating an additive manufacturing model according to claim 8, wherein the input parameters of each seed point further include control parameters adapted to control the gradient of material information.
- 根据权利要求11所述的生成增材制造模型的装置(600)，其特征在于，所述控制参数为适配于控制所述种子点的全部材料信息的共同控制参数，或所述控制参数为适配于控制所述种子点的各自材料信息的各自控制参数。The device (600) for generating an additive manufacturing model according to claim 11, wherein the control parameter is a common control parameter adapted to control all material information of the seed point, or the control parameter is Respective control parameters adapted to control respective material information of said seed points.
- 根据权利要求11所述的生成增材制造模型的装置(600)，其特征在于，The device (600) for generating an additive manufacturing model according to claim 11, characterized in that,所述确定模块(603)，用于计算第i个种子点的高斯函数f i(x，y，z)，其中： The determination module (603) is used to calculate the Gaussian function f i (x, y, z) of the i-th seed point, wherein:确定所述体素模型中的第j个体素的、第i个种子点的材料信息的组分权重w j，i，其中：
Determine the component weight w j,i of the material information of the i-th seed point of the j-th voxel in the voxel model, wherein:其中exp是以自然常数e为底的指数函数；(vx j，vy j，vz j)是第j个体素的坐标；(hx i，hy i，hz i)是第i个种子点的坐标；σ i是第i个种子点的控制参数；π是圆周率；(x，y，z)是任意点的坐标；i∈[1，N]；j∈[1，J]；J为体素的总数目。 Where exp is an exponential function with a natural constant e as the base; (vx j , vy j , vz j ) is the coordinate of the jth voxel; (hx i , hy i , hz i ) is the coordinate of the i-th seed point; σ i is the control parameter of the i-th seed point; π is the pi; (x, y, z) is the coordinate of any point; i∈[1,N]; j∈[1,J]; J is the voxel total number. - 根据权利要求13所述的生成增材制造模型的装置(600)，其特征在于，The device (600) for generating an additive manufacturing model according to claim 13, characterized in that,所述分配模块(604)，用于执行下列中的少一个：The allocation module (604) is configured to perform at least one of the following:当所述组分权重w j，i为0时，不为所述第j个体素分配所述第i个种子点的材料信息所指定的材料； When the component weight wj,i is 0, the material specified by the material information of the i-th seed point is not assigned to the j-th voxel;当所述组分权重w j，i为1时，为所述第j个体素全部分配所述第i个种子点的材料信息所指定的材料； When the component weight wj,i is 1, assign the material specified by the material information of the i-th seed point to all the j-th voxels;当所述组分权重w j，i处于0和1之间时，为所述第j个体素分配对应于所述组分权重w j，i的、所述第i个种子点的材料信息所指定的材料。 When the component weight w j, i is between 0 and 1, assign the jth voxel corresponding to the component weight w j, i , the material information of the ith seed point specified material.
- 一种生成增材制造模型的装置(700)，其特征在于，包括处理器(701)和存储器(702)；A device (700) for generating an additive manufacturing model, characterized in that it includes a processor (701) and a memory (702);所述存储器(702)中存储有可被所述处理器(701)执行的应用程序，用于使得所 述处理器(701)执行如权利要求1至7中任一项所述的生成增材制造模型的方法(100)。The memory (702) stores an application program executable by the processor (701), which is used to make the processor (701) execute the method for generating additives according to any one of claims 1 to 7. A method (100) of making a model.
- 一种计算机可读存储介质，其特征在于，其中存储有计算机可读指令，该计算机可读指令用于执行如权利要求1至7中任一项所述的生成增材制造模型的方法(100)。A computer-readable storage medium, characterized in that computer-readable instructions are stored therein, and the computer-readable instructions are used to execute the method (100) for generating an additive manufacturing model according to any one of claims 1 to 7 ).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/CN2021/121081 WO2023044926A1 (en) | 2021-09-27 | 2021-09-27 | Method and apparatus for generating additive manufacturing model, and computer-readable storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/CN2021/121081 WO2023044926A1 (en) | 2021-09-27 | 2021-09-27 | Method and apparatus for generating additive manufacturing model, and computer-readable storage medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2023044926A1 true WO2023044926A1 (en) | 2023-03-30 |
Family
ID=85719928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/CN2021/121081 WO2023044926A1 (en) | 2021-09-27 | 2021-09-27 | Method and apparatus for generating additive manufacturing model, and computer-readable storage medium |
Country Status (1)
| Country | Link |
|---|---|
| WO (1) | WO2023044926A1 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070160277A1 (en) * | 2006-01-12 | 2007-07-12 | Siemens Corporate Research, Inc. | System and Method For Segmentation of Anatomical Structures In MRI Volumes Using Graph Cuts |
| CN107209957A (en) * | 2015-01-30 | 2017-09-26 | 惠普发展公司有限责任合伙企业 | Represent to generate slice of data from voxel |
| CN107921701A (en) * | 2015-10-29 | 2018-04-17 | 惠普发展公司，有限责任合伙企业 | Color mapping in 3D printing |
| CN109872386A (en) * | 2019-01-18 | 2019-06-11 | 北京理工大学 | A kind of the physical property of product modeling method based on the accurate voxelization of STL model |
-
2021
- 2021-09-27 WO PCT/CN2021/121081 patent/WO2023044926A1/en unknown
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070160277A1 (en) * | 2006-01-12 | 2007-07-12 | Siemens Corporate Research, Inc. | System and Method For Segmentation of Anatomical Structures In MRI Volumes Using Graph Cuts |
| CN107209957A (en) * | 2015-01-30 | 2017-09-26 | 惠普发展公司有限责任合伙企业 | Represent to generate slice of data from voxel |
| CN107921701A (en) * | 2015-10-29 | 2018-04-17 | 惠普发展公司，有限责任合伙企业 | Color mapping in 3D printing |
| CN109872386A (en) * | 2019-01-18 | 2019-06-11 | 北京理工大学 | A kind of the physical property of product modeling method based on the accurate voxelization of STL model |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11335073B2 (en) | 3D print selection based on voxel property association and conflict resolution | |
| US20190088014A1 (en) | Surface modelling | |
| CN109685095B (en) | Classifying 2D images according to 3D arrangement type | |
| US20200356074A1 (en) | Method for setting printing properties of a three-dimensional object for additive manufacturing process | |
| CN107206692B (en) | Three-dimensional object representation | |
| CN114627219A (en) | Rendering method and device of three-dimensional scene data, storage medium and electronic device | |
| CN109544672A (en) | A kind of three-dimensional building model texture mapping method and device | |
| JP2022036918A (en) | Uv mapping on 3d object with the use of artificial intelligence | |
| CN109049716A (en) | Generation method, device, electronic equipment and the storage medium of 3 D-printing illustraton of model | |
| CN115100383A (en) | Three-dimensional reconstruction method, device and equipment for mirror surface object based on common light source | |
| JP2022546045A (en) | Computer-implemented method for generating a three-dimensional wireframe model of an object with multiple parts | |
| US11221609B2 (en) | Determining object volumes in virtual object space | |
| WO2023044926A1 (en) | Method and apparatus for generating additive manufacturing model, and computer-readable storage medium | |
| CN107209958B (en) | Three-dimensional object representation | |
| CN109983509A (en) | A kind of instant boolean operation method using geometric surface | |
| CN112560126B (en) | Data processing method, system and storage medium for 3D printing | |
| CN113591208A (en) | Oversized model lightweight method based on ship feature extraction and electronic equipment | |
| CN108025503B (en) | Generating parametric descriptions of three-dimensional objects | |
| Lin et al. | A feature-adaptive subdivision method for real-time 3D reconstruction of repeated topology surfaces | |
| US11366454B2 (en) | Generating a preview of a part to be printed | |
| US11822311B2 (en) | Generation of representations of three-dimensional objects using Boolean operations | |
| Horvat et al. | Inclusion test for polyhedra using depth value comparisons on the GPU | |
| US20220405447A1 (en) | Machine learning-based selective incarnation of computer-aided design objects | |
| IL298459A (en) | System and method for printing a three-dimensional object | |
| Martin et al. | Volumetric representation for object model acquisition |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 21958044 Country of ref document: EP Kind code of ref document: A1 |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |