JP2020075451A - Generation device for three-dimensional shape date, three-dimensional shape molding device, and generation program for three-dimensional shape data - Google Patents

Abstract

To efficiently generate a three-dimensional threshold matrix compared to the case in which three-dimensional threshold matrixes are generated one by one by operation of a user.SOLUTION: A generation device for three-dimensional shape data comprises: a basic shape reception part 50 which receives a basic shape for generating a three-dimensional threshold matrix used when shaping or not shaping of a plurality of voxels is calculated from the comparison result of three-dimensional shape date having a three-dimensional shape indicated by a plurality of voxels and a three-dimensional threshold matrix in which a threshold is arranged in a three-dimensional region corresponding to the basic shape; and a generation part 52 which generates the three-dimensional matrix in such a manner that the threshold gradually changes as the threshold is apart from the position corresponding to the basic shape.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a three-dimensional shape data generation device, a three-dimensional modeling device, and a three-dimensional shape data generation program.

  Patent Document 1 discloses a three-dimensional object to be molded, a dot forming unit for forming dots that form a supporting unit that supports the three-dimensional object, and a molding of the three-dimensional object and the supporting unit by the formed dots. And a control unit for controlling the object, wherein the control unit includes, in the support unit, an input value and a dither that represent a dot formation rate in voxels included in a voxel set representing the support unit. There is disclosed a three-dimensional object modeling apparatus that arranges dots in the voxel group so that a support structure that supports the three-dimensional object is formed based on a mask.

  In Patent Document 2, a head unit capable of ejecting a liquid, a curing unit that cures the liquid ejected from the head unit to form dots, and the shape of a three-dimensional object to be modeled are represented by a voxel set. Of the set, by forming dots in the voxels that the determination unit has determined to form dots, a modeling control unit that controls the operation of the head unit so that the three-dimensional object is modeled as a collection of dots. , The determination unit according to a comparison result of a formation index value that is a value corresponding to a dot formation rate in a voxel located inside the three-dimensional object in the voxel set, and a threshold value of a dither mask. Then, a three-dimensional object modeling apparatus is disclosed, which determines voxels to be dots-formed.

  In Patent Document 3, a measurement result receiving unit that receives a measurement result obtained by measuring the shape of the first shaped object output by the output device using the first three-dimensional data that defines the shape of the first shaped object, A correction data calculation unit that calculates correction data based on an error from a shape defined by the first three-dimensional data of the measurement result received by the measurement result reception unit, and a correction calculated by the correction data calculation unit There is disclosed a three-dimensional data generation device including a data correction unit that corrects the second three-dimensional data that defines the shape of the second model using the use data.

JP, 2017-109427, A JP, 2017-30177, A JP, 2008-1725, A

  To modulate the cycle of the basic shape to a desired cycle when generating the three-dimensional shape data using the three-dimensional threshold value matrix corresponding to the basic shape in order to model the three-dimensional shape in which the basic shape is repeatedly arranged. There was no way to generate the three-dimensional threshold matrix of Therefore, the three-dimensional threshold matrix needs to be created one by one by the user's operation, which is inefficient.

  INDUSTRIAL APPLICABILITY The present invention is a three-dimensional threshold matrix generation device capable of efficiently generating a three-dimensional threshold matrix as compared with a case where a three-dimensional threshold matrix is created one by one by a user operation. An object is to provide a generation device and a generation program of a three-dimensional threshold matrix.

  A three-dimensional threshold matrix generation device according to a first aspect is a three-dimensional threshold matrix in which three-dimensional shape data of a three-dimensional shape represented by a plurality of voxels and threshold values corresponding to a basic shape are arranged in a three-dimensional area. And, a basic shape receiving unit that receives a basic shape for generating the three-dimensional threshold value matrix used when calculating the presence or absence of modeling of the plurality of voxels from the comparison result, and as the distance from the position corresponding to the basic shape increases. A generating unit that generates the three-dimensional threshold matrix so that the threshold gradually changes.

  A three-dimensional threshold value matrix generation device according to a second aspect is the three-dimensional threshold value matrix generation device according to the first aspect, wherein the generation unit gradually increases the threshold value from a central portion of the basic shape toward an outer edge portion. The three-dimensional threshold matrix is generated so as to be large.

  A three-dimensional threshold value matrix generation device according to a third aspect is the three-dimensional threshold value matrix generation device according to the second aspect, wherein the generation unit is a pattern in which a predetermined shape including the basic shape is represented by a plurality of voxels. The three-dimensional threshold matrix is generated by calculating the number of adjacent voxels for each voxel of the piece.

  A three-dimensional threshold value matrix generation device according to a fourth aspect is the three-dimensional threshold value matrix generation device according to the third aspect, further comprising a parameter accepting unit that accepts a parameter for determining the number of the threshold values of the three-dimensional threshold value matrix. And a calculator that calculates the size of the three-dimensional threshold matrix using the size of the pattern piece and the parameters.

  A three-dimensional threshold value matrix generation device according to a fifth aspect is the three-dimensional threshold value matrix generation device according to the third aspect or the fourth aspect, further comprising a thickness acceptance unit that accepts the reference thickness of the basic shape, The unit generates the three-dimensional threshold matrix by using the number of adjacent voxels for each voxel of the pattern piece corresponding to the reference wall thickness received by the wall thickness receiving unit.

  A three-dimensional threshold value matrix generation device according to a sixth aspect is the three-dimensional threshold value matrix generation device according to the fifth aspect, wherein the wall thickness receiving unit receives a plurality of reference wall thicknesses, and the generation unit includes the plurality of reference wall thicknesses. The three-dimensional threshold value matrix is generated by accumulating the threshold values at the same position of the plurality of three-dimensional threshold value matrices generated for the plurality of pattern pieces corresponding to the respective reference wall thicknesses.

  A three-dimensional threshold value matrix generation device according to a seventh aspect is the three-dimensional threshold value matrix generation device according to the fifth or sixth aspect, wherein the wall thickness receiving unit sets at least one of a minimum wall thickness and a maximum wall thickness. When the receiving unit receives the minimum wall thickness, the generating unit generates the three-dimensional threshold matrix so that the wall thickness does not become smaller than the minimum wall thickness, and when the maximum wall thickness is received, The three-dimensional threshold matrix is generated so that the wall thickness does not become larger than the maximum wall thickness.

  A three-dimensional threshold matrix generation device according to an eighth aspect is the three-dimensional threshold matrix generation device according to any of the third to seventh aspects, wherein the generation unit calculates for each voxel of the pattern piece. The number of the presence or absence of the adjacent voxels is weighted according to the type of contact with the adjacent voxels.

  A three-dimensional threshold value matrix generation device according to a ninth aspect is the three-dimensional threshold value matrix generation device according to the eighth aspect, wherein the generation unit has the types of contact in the order of surface contact, line contact, and point contact. Weighting is performed so that the weight becomes larger.

  A three-dimensional threshold value matrix generation device according to a tenth aspect is the three-dimensional threshold value matrix generation device according to any one of the eighth and ninth aspects, wherein the generation unit calculates for each voxel of the pattern piece. The number of presence / absence of the adjacent voxels is weighted with a threshold value based on the connection strength with the adjacent voxels.

  A three-dimensional shape data generation device according to an eleventh aspect uses the three-dimensional threshold value matrix generated by the three-dimensional threshold value matrix generation device according to any one of the first to tenth aspects. The voxel is provided with a calculation unit that calculates the presence or absence of modeling.

  A three-dimensional threshold matrix generation program according to a twelfth aspect is a program for causing a computer to function as each unit of the three-dimensional threshold matrix generation device according to any one of the first to tenth aspects.

  According to the first, eleventh, and twelfth aspects, it is possible to efficiently generate the three-dimensional threshold matrix as compared with the case where the three-dimensional threshold matrix is created one by one by the operation of the user. Have.

  According to the second aspect, the thickness of the basic shape can be easily adjusted as compared with the case where the threshold value is set regardless of the distance from the basic shape.

  According to the third aspect, it is possible to easily generate the three-dimensional threshold matrix as compared with the case where the threshold is set for each voxel of the pattern piece regardless of the number of adjacent voxels. Have.

  According to the fourth aspect, it is possible to generate a three-dimensional threshold matrix of a desired size, as compared with the case where the parameter for determining the number of thresholds of the three-dimensional threshold matrix is not accepted.

  According to the fifth aspect, compared to the case where the reference wall thickness of the basic shape is not accepted, it is possible to generate various types of three-dimensional threshold matrixes.

  According to the sixth aspect, it is possible to generate various types of three-dimensional threshold matrices as compared with the case where only one reference thickness of the basic shape is accepted.

  According to the seventh aspect, the effect that the wall thickness of the three-dimensional shape can be set to the minimum wall thickness or more or the maximum wall thickness or less as compared with the case where at least one of the minimum wall thickness and the maximum wall thickness is not accepted Have.

  According to the eighth aspect, as compared with the case where the number of presence / absence of adjacent voxels calculated for each voxel of the pattern piece is calculated regardless of the type of contact with the adjacent voxels, various types of three-dimensional threshold values are used. This has the effect that a matrix can be generated.

  According to the ninth aspect, there is an effect that the shape can be modulated in the order of surface contact, line contact, and point contact.

  According to the tenth aspect, as compared with the case where the number of presence / absence of adjacent voxels calculated for each voxel of the pattern piece is calculated regardless of the connection strength with the adjacent voxels, various types of three-dimensional threshold matrixes. Can be generated.

It is a block diagram of a three-dimensional modeling system. It is a block diagram of the generator of three-dimensional shape data. It is a block diagram showing a functional configuration of a three-dimensional shape data generation device. It is a figure which shows an example of the three-dimensional shape represented by voxel data. It is a block diagram of a three-dimensional modeling apparatus. It is a flow chart which shows a flow of processing by a generation program of three-dimensional shape data. It is a figure which shows an example of a three-dimensional threshold value matrix. It is a figure which shows an example of the threshold value table which comprises a three-dimensional threshold value matrix. It is a figure for demonstrating presence or absence of discharge of modeling material. It is a figure which shows an example of a basic shape. It is a figure for demonstrating presence or absence of discharge of modeling material. It is a figure which shows an example of a basic shape. It is a figure which shows an example of a threshold value matrix, a 1st attribute value, and a 2nd attribute value. It is a figure which shows an example of a threshold value matrix, a 1st attribute value, and a 2nd attribute value. It is a figure which shows an example of a threshold value matrix, a 1st attribute value, and a 2nd attribute value. It is a figure which shows an example of a threshold value matrix, a 1st attribute value, and a 2nd attribute value. It is a flow chart which shows a flow of processing by a generation program of a three-dimensional threshold matrix. It is a figure which shows an example of the condition setting screen for setting the conditions at the time of generating a three-dimensional threshold value matrix. It is a figure which shows an example of a pattern piece. It is a figure which shows the cross section of a pattern piece. It is a figure for demonstrating the case where the number of the presence or absence of an adjacent voxel is calculated. It is a figure which shows an example of a three-dimensional threshold value matrix. It is a diagram which shows the relationship between wall thickness and a threshold value. It is a figure which shows an example of the pattern piece of several wall thickness. It is a figure which shows an example of a three-dimensional threshold value matrix. It is a diagram which shows the relationship between wall thickness and a threshold value. It is a figure which shows an example of a three-dimensional threshold value matrix. It is a diagram which shows the relationship between wall thickness and a threshold value.

  Embodiments for carrying out the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a configuration diagram of a three-dimensional modeling system 1 according to the present embodiment. As shown in FIG. 1, the 3D modeling system 1 includes a 3D shape data generation device 10 and a 3D modeling device 100. The generation device 10 also has a function as a generation device of a three-dimensional threshold value matrix described later. In the present embodiment, a case will be described in which the generation device 10 functions as a generation device for three-dimensional shape data and also as a generation device for a three-dimensional threshold value matrix, but both may be separate devices.

  Next, a configuration of the three-dimensional shape data generation device 10 according to the present embodiment will be described with reference to FIG.

  The generation device 10 is composed of, for example, a personal computer or the like, and includes a controller 12. The controller 12 includes a CPU (Central Processing Unit) 12A, a ROM (Read Only Memory) 12B, a RAM (Random Access Memory) 12C, a non-volatile memory 12D, and an input / output interface (I / O) 12E. The CPU 12A, the ROM 12B, the RAM 12C, the non-volatile memory 12D, and the I / O 12E are connected to each other via the bus 12F.

  Further, the I / O 12E is connected to the operation unit 14, the display unit 16, the communication unit 18, and the storage unit 20.

  The operation unit 14 includes, for example, a mouse and a keyboard.

  The display unit 16 is composed of, for example, a liquid crystal display or the like.

  The communication unit 18 is an interface for performing data communication with an external device such as the three-dimensional modeling device 100.

  The storage unit 20 is composed of a non-volatile storage device such as a hard disk, and includes a three-dimensional shape data generation program, a three-dimensional threshold value matrix generation program, three-dimensional shape data (voxel data), and the generated three-dimensional threshold value, which will be described later. The matrix etc. are stored. The CPU 12A reads and executes the three-dimensional shape data generation program or the three-dimensional threshold matrix generation program stored in the storage unit 20.

  Next, a functional configuration of the CPU 12A when the generation device 10 functions as a three-dimensional threshold value matrix generation device will be described.

  As shown in FIG. 3, the CPU 12A functionally includes a basic shape reception unit 50, a generation unit 52, a parameter reception unit 54, a calculation unit 56, and a wall thickness reception unit 58.

  The basic shape receiving unit 50 determines a plurality of types from the comparison result of the three-dimensional shape data of the three-dimensional shape represented by a plurality of voxels and the three-dimensional threshold matrix in which the threshold values are arranged in the three-dimensional area corresponding to the basic shape. The basic shape for generating the three-dimensional threshold value matrix used when calculating the presence / absence of modeling of the voxel is received. For example, the user selects a desired basic shape from the plurality of basic shapes displayed on the display unit 16.

  The generation unit 52 generates the three-dimensional threshold matrix so that the threshold gradually changes as the distance from the position corresponding to the basic shape increases.

  The parameter receiving unit 54 receives a parameter for determining the number of thresholds of the three-dimensional threshold matrix, for example, a voxel pitch of the three-dimensional threshold matrix.

  The calculation unit 56 calculates the size of the three-dimensional threshold matrix using the size of the pattern piece in which a predetermined shape including the basic shape is represented by a plurality of voxels and the parameters received by the parameter reception unit 54.

  The wall thickness receiving unit 58 receives the wall thickness of the basic shape. The wall thickness means, for example, the thickness of the skeleton portion of the basic shape. For example, when the skeleton portion of the basic shape is a rectangular shape, it means the width of the rectangular shape, and when the skeleton portion of the basic shape is a sphere, it means the diameter of the sphere.

  When the wall thickness reception unit 58 receives the wall thickness, the generation unit 52 uses the number of presence / absence of adjacent voxels for each voxel of the pattern piece corresponding to the wall thickness received by the wall thickness reception unit 58 to perform three-dimensional processing. Generate a threshold matrix.

  FIG. 4 shows a three-dimensional shape 32 represented by three-dimensional shape data (voxel data) in which the three-dimensional shape is represented by a set of voxels. As shown in FIG. 4, the three-dimensional shape 32 is composed of a plurality of voxels 34.

  Here, the voxel 34 is a basic element of the three-dimensional shape 32, and for example, a rectangular parallelepiped is used, but the voxel 34 is not limited to the rectangular parallelepiped and may be a sphere or a cylinder. By stacking the voxels 34, a desired three-dimensional shape is expressed.

  As a three-dimensional shaping method for shaping a three-dimensional shape, for example, a heat melting laminating method (FDM: Fused Deposition Modeling) for shaping a three-dimensional shape by melting and laminating a thermoplastic resin, a laser beam is applied to a powder metal material. A laser sintering method (SLS method: Selective Laser Sintering) in which a three-dimensional shape is formed by irradiating and sintering is applied, but another three-dimensional forming method may be used. In this embodiment, a case where a three-dimensional shape is formed by using the hot melt laminating method will be described.

  Next, a three-dimensional modeling apparatus that models a three-dimensional shape using the three-dimensional shape data generated by the three-dimensional shape data generating apparatus 10 will be described.

  FIG. 5 shows the configuration of the three-dimensional modeling apparatus 100 according to this embodiment. The three-dimensional modeling apparatus 100 is an apparatus that models a three-dimensional shape by a hot melt laminating method.

  As shown in FIG. 5, the three-dimensional modeling apparatus 100 includes an ejection head 102, an ejection head driving unit 104, a modeling table 106, a modeling table driving unit 108, an acquisition unit 110, and a control unit 112. The ejection head 102, the ejection head drive unit 104, the modeling table 106, and the modeling table driving unit 108 are examples of the modeling unit.

  The ejection head 102 includes a modeling material ejection head that ejects a modeling material for modeling the three-dimensional shape 40, and a support material ejection head that ejects a support material. The support material is used for supporting an overhanging portion (also referred to as “overhanging portion”) of a three-dimensional shape until the shaping is completed, and is removed after the shaping is completed.

  The ejection head 102 is driven by the ejection head driving unit 104 and is two-dimensionally scanned on the XY plane. Further, the modeling material ejection head may include a plurality of ejection heads corresponding to the modeling materials having a plurality of types of attributes (for example, colors).

  The modeling table 106 is driven by the modeling table driving unit 108 and moved up and down in the Z-axis direction.

  The acquisition unit 110 acquires the three-dimensional shape data and the support material data generated by the three-dimensional shape data generation device 10.

  The control unit 112 drives the ejection head driving unit 104 to drive the ejection head 102 so that the modeling material is ejected according to the three-dimensional shape data acquired by the acquisition unit 110 and the support material is ejected according to the support material data. The two-dimensional scanning is performed and the ejection of the modeling material and the support material by the ejection head 102 is controlled.

  In addition, the control unit 112 drives the modeling table driving unit 108 and lowers the modeling table 106 by a predetermined stacking interval each time the modeling of each layer is completed. As a result, a three-dimensional shape based on the three-dimensional shape data is formed.

  Next, with reference to FIG. 6, an operation when the generation device 10 according to the present embodiment functions as a generation device for three-dimensional shape data will be described. The generation process shown in FIG. 6 is executed by executing the three-dimensional shape data generation program by the CPU 12A. The generation process shown in FIG. 6 is executed, for example, when the user's operation instructs the execution of the generation program. In the present embodiment, the description of the support material data generation process is omitted.

  In the present embodiment, a case will be described in which each voxel is set with a strength value representing the strength of the voxel as the first attribute value, and the presence or absence of modeling of the voxel is calculated as the second attribute value. ..

  In step S100, the voxel data corresponding to the three-dimensional shape of the modeling target is acquired by reading from the storage unit 20, for example. In addition, you may acquire voxel data by communication from an external device via the communication part 18.

  In step S102, display data of a three-dimensional shape is generated from the voxel data acquired in step S100 and displayed on the display unit 16.

  In step S103, a reception screen for receiving an adjustment coefficient, which will be described later, is displayed on the display unit 16 and the user inputs the adjustment coefficient. The adjustment coefficient is set for each of the three axes, which are the X axis, the Y axis, and the Z axis, which are orthogonal to each other. The user may input an adjustment coefficient for each of the X-axis, Y-axis, and Z-axis, or if one adjustment coefficient is input, the input adjustment coefficient will be the X-axis, Y-axis, and Z-axis. You may make it set as an adjustment coefficient of all the axes.

  In step S104, a three-dimensional threshold matrix used when calculating the presence / absence of modeling of each voxel is set. In the three-dimensional threshold matrix, thresholds are arranged in the three-dimensional area corresponding to a predetermined basic shape.

  FIG. 7 shows a three-dimensional threshold matrix M as an example. As shown in FIG. 7, the three-dimensional threshold matrix M is composed of seven layers of threshold tables Z1 to Z7.

  FIG. 8 shows an example of the threshold tables Z1 to Z7. As will be described later, when calculating the presence / absence of modeling of each voxel, the threshold tables Z1 to Z7 are used as a dither matrix and the same processing as so-called halftone processing is performed on the voxel data of each layer corresponding to each threshold table. Run. That is, each threshold of the threshold table and the intensity value of the corresponding voxel are compared, and if the intensity value is equal to or more than the threshold, the modeling of the voxel is “present”, and if the intensity value is less than the threshold, The voxel shape is "none". Here, in the present embodiment, it is assumed that the value that the intensity value can take is “0” or more. In this case, when the threshold is “0”, the modeling of the voxel corresponding to the threshold is always “present”. Therefore, the part where the threshold value is “0” corresponds to the basic shape.

  In the example of FIG. 8, the threshold value “0” is set in the center of all layers, and the threshold value table Z4 of the fourth layer, which is the center layer in the Z-axis direction, has the threshold value “0” set in a cross shape in the XY plane. Has been done. That is, the threshold value of the position corresponding to the basic shape is set to the minimum value in the range of possible values of the threshold value. Therefore, when the three-dimensional threshold matrix M is set, if all the intensity values of each voxel are "0", the modeling material is ejected to the position indicated by "■" as shown in FIG. It will be. Therefore, the basic shape of the three-dimensional threshold matrix M is the basic shape K as shown in FIG.

  In addition, as shown in FIG. 8, all threshold values other than the positions corresponding to the basic shapes of the threshold tables Z1 to Z7 are “35” or more. Therefore, for example, when all the intensity values of each voxel are less than “35”, the basic shape K is as shown in FIG. Further, for example, when all the intensity values of each voxel are “50”, the molding material is discharged to the position indicated by “■” as shown in FIG. 11. Therefore, the basic shape of the three-dimensional threshold matrix M becomes a basic shape K2 obtained by thickening the basic shape K shown in FIG. 10, as shown in FIG.

  Further, as shown in FIG. 8, among the threshold values set in the threshold value tables Z1 to Z7, the threshold values other than the positions corresponding to the basic shape are set to increase from the center toward the outside. Therefore, each threshold value set in the three-dimensional threshold value matrix M is set so as to increase from the center of the three-dimensional area indicated by the three-dimensional threshold value matrix M toward the outside. That is, the respective thresholds set in the three-dimensional threshold matrix M are set so that the proportion of voxels in which the modeling is “present” decreases as going outward from the center of the three-dimensional area indicated by the three-dimensional threshold matrix M. Has been done. In other words, the threshold value is set so that the intensity increases toward the center of the three-dimensional area indicated by the three-dimensional threshold value matrix M. Note that as the size of the three-dimensional threshold matrix becomes smaller, the size of the basic shape becomes smaller and the three-dimensional shape becomes a dense structure, so that it becomes harder. On the other hand, as the size of the three-dimensional threshold matrix increases, the size of the basic shape increases, and the three-dimensional shape becomes a coarse structure, resulting in softness. Therefore, a small size three-dimensional threshold matrix may be set for the portion to be made hard, and a large three-dimensional threshold matrix may be set to the portion to be made soft.

  In the present embodiment, the storage unit 20 stores three-dimensional threshold matrices corresponding to various types of basic shapes. The user operates the operation unit 14 to select a desired basic shape, that is, a three-dimensional threshold matrix. The number of three-dimensional threshold matrices to be selected is not limited to one, and a plurality of three-dimensional threshold matrices may be selected for each three-dimensional shape portion.

  In step S106, a plurality of intensity values set for each of the plurality of voxels represented by the voxel data, the three-dimensional threshold matrix set in step S104, and the adjustment coefficient received in step S103 The presence or absence of modeling for each voxel is calculated. Specifically, as described above, the threshold tables Z1 to Z7 are used as the dither matrix, and the so-called halftone processing is performed on the voxel data of each layer corresponding to each threshold table. That is, the threshold value of the threshold table and the intensity value of the voxel at the position corresponding to the threshold value are compared, and if the intensity value is equal to or greater than the threshold value, the modeling of the voxel is “present”, and the intensity value is less than the threshold value. Performs the process of setting the modeling of the voxel as “none” for each threshold in the threshold table.

  Here, the first attribute value of the voxel is V1 (i, j, k), the threshold value of the three-dimensional threshold matrix is Mt (l, m, n), and the second attribute value is V2 (i, j, k). In such a case, the second attribute value, that is, the presence or absence of modeling is calculated by the following equation.

V2 (i, j, k) = VmaxM, V1 (i, j, k) <Mt (l, m, n)
... (1)
V2 (i, j, k) = VmaxP, V1 (i, j, k) ≧ Mt (l, m, n)
... (2)

  Here, i is the coordinate value of the X axis, j is the coordinate value of the Y axis, and k is the coordinate value of the Z axis. In addition, l, m, and n represent the X coordinate, Y coordinate, and Z coordinate of the threshold value of the three-dimensional threshold value matrix, and are represented by the following equation.

l = MOD (Ax × i, Mx) (3)
m = MOD (Ay × j, My) (4)
n = MOD (Az × k, Mz) (5)

  Here, MOD (a, b) represents the remainder when a is divided by b. Therefore, l is the remainder when Ax × i is divided by Mx. Similarly, m is the remainder when Ay × j is divided by My. Similarly, n is a remainder when Az × k is divided by Mz. Note that Mx is the size of the three-dimensional threshold matrix in the X-axis direction, that is, the number of threshold values in the X-axis direction. Similarly, My is the size of the three-dimensional threshold matrix in the Y-axis direction, that is, the number of threshold values in the Y-axis direction. Similarly, Mz is the size of the three-dimensional threshold matrix in the Z-axis direction, that is, the number of threshold values in the Z-axis direction.

  Moreover, Ax, Ay, and Az are represented by the following equations.

Ax = Ax0 × V1 (i, j, k) / VmaxP + 1 (6)
Ay = Ay0 × V1 (i, j, k) / VmaxP + 1 (7)
Az = Az0 × V1 (i, j, k) / VmaxP + 1 (8)

  Here, Ax0 is an X-axis adjustment coefficient, Ay0 is a Y-axis adjustment coefficient, Az0 is a Z-axis adjustment coefficient, and 0 ≦ Ax0 ≦ Bx, 0 ≦ Ay0 ≦ By, and 0 ≦ Az0 ≦ Bz. Bx is the maximum value that the adjustment coefficient Ax can take. Similarly, By is the maximum value that the adjustment coefficient Ay can take, and Bz is the maximum value that the adjustment coefficient Az can take. In the present embodiment, the case where Bx = By = Bz = 1 is described as an example, but the maximum value of the adjustment coefficient is not limited to 1. When all the adjustment coefficients are set to “0”, that is, when Ax0 = Ay0 = Az0 = 0, the cycle of the three-dimensional threshold matrix is not adjusted. Further, as the adjustment coefficient becomes larger than 0, the degree of adjustment becomes large. Therefore, in order to increase the maximum value of the adjustment degree, the values of Bx, By and Bz may be increased.

  Further, VmaxM is a value obtained by adding a negative sign "-" to the upper limit value of the value that can be taken by V1 (i, j, k). In the present embodiment, as an example, V1 (i, j, k) is represented by 8 bits and can take a value of 0 to 255. Therefore, VmaxM = −255. VmaxP is a value obtained by adding a positive sign “+” to the upper limit value of the value that can be taken by V1 (i, j, k). Therefore, VmaxP = + 255. It should be noted that VmaxM means “without modeling”, and VmaxP means “with modeling”.

  In this way, when the first attribute value V1 (i, j, k) is less than the threshold value Mt (l, m, n), the second attribute value V2 (i, j, k) becomes VmaxM, and " There is no modeling ”. Further, when the first attribute value V1 (i, j, k) is equal to or larger than the threshold value Mt (l, m, n), the second attribute value V2 (i, j, k) becomes VmaxP, which means “there is molding. Will be

  For example, as shown in FIG. 13, a case where the threshold matrix Mt1 is compared with the first voxel attribute value V1 will be described. The adjustment coefficient is Ax0 = Ay0 = Az0 = 0, that is, the case where the cycle of the three-dimensional threshold matrix Mt1 is not adjusted will be described.

  The three-dimensional threshold matrix Mt1 shown in FIG. 13 is set in multiple values so as to gradually change from the threshold “0” corresponding to the basic shape. Specifically, the threshold matrix Mt1 is composed of, for example, four types of thresholds “0”, “80”, “160”, and “255”, and the distance from the threshold “0” corresponding to the basic shape is This is a matrix in which the threshold value increases as it increases. Then, it is assumed that the first attribute value V1 of each voxel is uniformly “70”. In this case, as shown in FIG. 13, the second attribute value V2 is a cross shape in which one voxel at the center in both the X direction and the Y direction is “modeled”.

  Further, as shown in FIG. 14, it is assumed that the first attribute value V1 of each voxel is uniformly “90”. In this case, the second attribute value V2 is a cross shape having a larger thickness than the cross shape shown in FIG. 13 for the three central voxels in both the X and Y directions.

  Next, as shown in FIG. 15, the threshold value of the threshold value matrix is the threshold value “0” which is the first threshold value corresponding to the basic shape and the threshold value “255” which is the second threshold value corresponding to other than the basic shape. A case will be described in which the threshold matrix Mt2 that is set to be a binary value is used. The adjustment coefficient is Ax0 = Ay0 = Az0 = 0, that is, the case where the cycle of the three-dimensional threshold matrix Mt2 is not adjusted will be described.

  As shown in FIG. 15, it is assumed that the first attribute value V1 is set to a value of “0” to “255” such that the value increases from the left end to the right end in the X direction of FIG. In this case, as shown in FIG. 15, since the cycle of the threshold matrix Mt2 is not adjusted, the second attribute value V2 of the voxel corresponding to the shape in which the two basic shapes are regularly arranged in the X direction is “printed”. Becomes

  Further, in the example of FIG. 15, when the adjustment coefficient is Ax0 = Ay0 = Az0 = 1, that is, when the cycle of the three-dimensional threshold value matrix Mt2 is adjusted, the coordinates of the three-dimensional threshold value matrix Mt2 to be compared with the first attribute value V1. The scale changes. For this reason, as shown in FIG. 16, the second attribute value V2 of the voxel corresponding to the shape in which the basic shape becomes denser toward the right end in the X direction is “with modeling”.

  As described above, by changing the adjustment coefficient and the threshold matrix, the physical property value realized by the three-dimensional shape is finely adjusted.

  In step S108, the data representing the presence / absence of modeling of each voxel calculated in step S106 is transmitted to the 3D modeling apparatus 100 as voxel data.

  The acquisition unit 110 of the 3D modeling apparatus 100 acquires the voxel data transmitted from the 3D shape data generation apparatus 10. Further, the control unit 112 drives the ejection head drive unit 104 to two-dimensionally scan the ejection head 102 so that the modeling material is ejected according to the voxel data acquired by the acquisition unit 110, and the modeling by the ejection head 102 is performed. Control the discharge of material. Thereby, a three-dimensional shape is formed.

  Next, with reference to FIG. 17, an operation when the generation device 10 according to the present embodiment functions as a three-dimensional threshold value matrix generation device will be described. The generation processing shown in FIG. 17 is executed by executing the generation program of the three-dimensional threshold matrix by the CPU 12A. The generation process shown in FIG. 17 is executed, for example, when the execution of the generation program is instructed by a user operation.

  In step S200, for example, a setting screen 60 as shown in FIG. 18 is displayed on the display unit 16 as a setting screen for setting conditions for generating the three-dimensional threshold matrix. As shown in FIG. 18, the setting screen 60 has a pattern piece selection area 62 for selecting a pattern piece, an external file reading button 64 for instructing reading of an external file in which the pattern piece is defined, and a three-dimensional threshold matrix. Voxel pitch input field 66 for inputting the voxel pitch of, a reference wall thickness input area 68 for inputting a reference wall thickness to be a reference when modulating the pattern piece, for instructing to maintain the minimum wall thickness Check box 70, a check box 72 for instructing to maintain the maximum wall thickness, a check box 74 for instructing weighting according to the type of contact with an adjacent voxel, and a connection strength with an adjacent voxel. A check box 76 for instructing weighting based on (link value), an execution button 78 for instructing execution of the three-dimensional threshold matrix generation process, and a cancel for canceling the value input to the setting screen 60. The button 80 is included.

  In the example of FIG. 18, five pattern pieces P1 to P3 are displayed, and the pattern piece P1 is selected by the user operating the operation unit 14. Further, other pattern pieces are also displayed by moving the slide bar SB left and right. Furthermore, the pattern piece may be accepted by reading an external file in which the pattern piece is defined. In this case, the external file read button 64 may be pressed to specify the external file.

  Here, the pattern piece is a predetermined shape including a basic shape represented by a plurality of voxels. Note that a cube is given as the predetermined shape, but other shapes such as a rectangular parallelepiped other than a cube may be used.

  In the present embodiment, as an example, a case will be described in which a pattern piece P1 having a three-columnar basic shape as shown in FIG. 19 is selected.

  Further, the user inputs the voxel pitch of the three-dimensional threshold matrix in the voxel pitch input field 66 in addition to selecting the pattern piece. Further, the reference thickness is input to the reference thickness input area 68 as needed. Note that a plurality of reference wall thicknesses may be input.

  Further, the user checks the check box 70 to instruct to maintain the minimum wall thickness, and checks the check box 72 to instruct to maintain the maximum wall thickness as necessary. In addition, the user may check the check box 74 as necessary to instruct weighting according to the type of contact with the adjacent voxel, or check the check box 76 to connect with the adjacent voxel. The weighting is instructed based on the strength.

  In step S202, it is determined whether a pattern piece has been selected. That is, it is determined whether the user has selected a desired pattern piece from the pattern piece selection area 62 by operating the operation unit 14 and whether the external file read button 64 has been pressed and an external file has been designated.

  When the pattern piece is selected, the process proceeds to step S204, and when the pattern piece is not selected, the process proceeds to step S222.

  In step S204, the file in which the selected pattern piece is defined is read from the storage unit 20.

  In step S206, it is determined whether or not the voxel pitch of the three-dimensional threshold matrix is input to the voxel pitch input field 66. In the present embodiment, the case where a common value is input in each direction of the X, Y, and Z axes in the voxel pitch input field 66 will be described, but a voxel pitch input field may be provided for each axis. In addition, in the present embodiment, the case where the voxel pitch is the number of voxels per 1 mm will be described as an example, but the size per voxel may be used. That is, it may be a parameter for determining the number of thresholds of the three-dimensional threshold matrix.

  Then, if the voxel pitch is input, the process proceeds to step S208, and if the voxel pitch is not input, the process proceeds to step S222.

  In step S208, the number of thresholds in the three-dimensional threshold matrix is calculated. Specifically, the number of thresholds of the three-dimensional threshold matrix is calculated based on the size of the pattern piece read in step S204 and the voxel pitch input in the voxel pitch input field 66. Here, the size of the pattern piece is predetermined, and the unit is millimeter as an example. Therefore, by multiplying the size of the pattern piece by the voxel pitch, the number of thresholds of the three-dimensional threshold matrix common to each of the X, Y, and Z axes is calculated. When the voxel pitch is the size per voxel, the number of thresholds in the three-dimensional threshold matrix may be calculated by dividing the size of the pattern piece by the voxel pitch.

  In step S210, it is determined whether the execute button 78 has been pressed. If the execute button 78 is pressed, the process proceeds to step S212, and if the execute button 78 is not pressed, the process proceeds to step S218.

  In step S212, the pattern piece is divided into a plurality of voxels so that the number of voxels in each direction of the X, Y, and Z axes of the pattern piece read in step S204 becomes the number of voxels calculated in step S208. At this time, the pattern piece is divided into a plurality of voxels such that the thickness of the pattern piece becomes the thickness input in the reference thickness input area 68. If nothing is input in the reference wall thickness input area 68, a predetermined wall thickness, for example, 1 mm may be used as the reference wall thickness.

  In addition, in the present embodiment, a case where the number of voxels in each of the X, Y, and Z axes of the pattern piece is 25 will be described. FIG. 20 shows a cross section in the XY plane at the Z direction central position of the pattern piece P1. In the pattern piece P1 shown in FIG. 20, the cross section in the XY plane of the pattern piece having a basic wall thickness of 1 mm is shown. As shown in FIG. 20, “1”, that is, “with voxel”, is set in the voxel at the position corresponding to the basic shape, and “0”, that is, “without voxel” in the voxel at the position other than the basic shape. Is set.

  In step S214, the number of presence / absence of adjacent voxels is calculated for each voxel forming the pattern piece.

  As shown in FIG. 21, there are 26 voxels with voxel numbers “1” to “26” around the target voxel BX which is the center of the processing target. Therefore, in the present embodiment, for each voxel, among the 27 voxels in which the surrounding 26 voxels and the number of target voxels BX are summed, “1”, that is, the voxel with which voxels are present is set. Calculate the number of

  Then, in step S216, the threshold value is obtained by normalizing the number of surrounding voxels with “voxels” calculated for each voxel by the maximum value of the voxel attribute values of the three-dimensional shape data.

  For example, the maximum value of the number of voxels with "voxels around" is Nmax, the number of voxels with "voxels around" is N, the maximum possible value of the voxel attribute value of the three-dimensional shape data is Bmax, and the threshold is TH. In that case, the threshold value TH is calculated by the following equation.

TH = {(Nmax-N) / Nmax} × Bmax (1)

  Note that the possible values of the number of voxels “with voxels” in the surroundings are “0” to “27”, so Nmax is “27”. Further, if the values that the voxel attribute values of the three-dimensional shape data can take are "0" to "255", Bmax is "255". Further, the threshold value TH calculated by the above equation (1) may be adjusted appropriately. For example, the first digit of the calculated threshold value TH or the portion after the decimal point may be rounded off, rounded up, or rounded down. Also, the threshold TH may be increased or decreased within a range that does not match other thresholds. By calculating the threshold TH in this way, a three-dimensional threshold matrix in which the threshold is in the range of “0” to “255” and the threshold of 28 gradations is set is generated. Note that for each voxel, the number of voxels for which “no voxel” is set among the surrounding voxels is calculated, and from the maximum value “27” of the surrounding “no voxels” to the surrounding “no voxels”. The threshold TH may be calculated using a value obtained by subtracting the number of voxels.

  FIG. 22 shows an example of the three-dimensional threshold matrix. The three-dimensional threshold value matrix M1 shown in FIG. 22 is a three-dimensional threshold value matrix having threshold values in the range of "0" to "255" and 28 gradations.

  Also, as shown in FIG. 22, the three-dimensional threshold matrix M1 is such that the threshold gradually changes as it moves away from the position corresponding to the basic shape, and more specifically, from the center of the basic shape toward the outer edge. The threshold is set so that the threshold gradually increases.

  FIG. 23 shows the relationship between the thickness of the three-dimensional threshold matrix M1 thus generated and the threshold. As shown in FIG. 23, the intermediate value of the threshold values corresponds to 1 mm set as the reference wall thickness.

  When a plurality of reference wall thicknesses are input to the reference wall thickness input area 68, the number of voxels “with voxels” around the voxel of the pattern piece corresponding to each reference wall thickness is calculated. Then, the number of voxels “with voxels” in the surroundings calculated for each voxel of each pattern piece is integrated for each same position, that is, the sum is calculated. Then, the threshold value is calculated by the above equation (1) using the calculated sum. As a result, when the number of pattern pieces is n, the gradation number of the threshold is 28 × n. For example, as shown in FIG. 18, a case where three types of reference wall thicknesses of 0.5 mm, 1.0 mm, and 2.0 mm are set will be described. In this case, as shown in FIG. 24, the pattern pieces P1-1, P1-2, and P1-3 having the reference wall thicknesses of 0.5 mm, 1.0 mm, and 2.0 mm are set, and the threshold gradation number is 28 × 3 = 84.

  FIG. 25 shows a three-dimensional threshold matrix M2 generated using the pattern pieces P1-1, P1-2, P1-3. Further, FIG. 26 shows the relationship between the thickness of the three-dimensional threshold matrix M2 and the threshold. In this case, as shown in FIG. 26, the intermediate value of the threshold value corresponds to the reference thickness of 1 mm, 75% of the maximum value of the threshold value corresponds to the reference thickness of 2 mm, and the value of 25% of the maximum value of the threshold value. Corresponds to a standard wall thickness of 0.5 mm.

  If the check box 70 is checked and the minimum wall thickness is maintained, the threshold is set so that the three-dimensional shape to be formed has the minimum wall thickness or more. Specifically, among the threshold values of the generated three-dimensional threshold value matrix, all the threshold values at the positions where the thickness is less than the minimum thickness are set to “0” which is the minimum threshold value. By modeling the three-dimensional shape using the three-dimensional threshold value matrix in which the threshold values are set in this way, a three-dimensional shape having a wall thickness equal to or greater than the minimum wall thickness is modeled.

  When the check box 72 is checked and the maximum thickness is set to be maintained, the threshold is set so that the three-dimensional shape to be formed has the maximum thickness or less. Specifically, among the threshold values of the generated three-dimensional threshold value matrix, all the threshold values at the positions exceeding the maximum wall thickness are set to “256”, which is larger than the maximum threshold value of “255”, for example. By modeling a three-dimensional shape using the three-dimensional threshold value matrix in which the threshold values are set in this way, a three-dimensional shape having a wall thickness equal to or smaller than the maximum wall thickness is modeled.

  In FIG. 27, three types of pattern pieces P1-1, P1-2, P1-3 having the reference thicknesses of 0.5 mm, 1.0 mm and 2.0 mm shown in FIG. And the three-dimensional threshold matrix M3 generated when set to maintain maximum wall thickness. The three-dimensional threshold matrix M3 shown in FIG. 27 corresponds to the three-dimensional threshold matrix M2 shown in FIG. 25, that is, the three-dimensional threshold matrix M2 generated when the minimum wall thickness and the maximum wall thickness are not set to be maintained. By comparison, all of the threshold values at positions where the minimum thickness is less than 0.5 mm are set to “0”, which is the minimum threshold value, and the threshold values at positions exceeding 2.0 mm, which is the maximum thickness, are set. All are set to "256" which is larger than "255" which is the maximum value of the threshold.

  Further, FIG. 28 shows the relationship between the wall thickness of the three-dimensional threshold matrix M3 and the threshold. In this case, as shown in FIG. 28, the threshold value less than the maximum value “256”, that is, the threshold value “255” or less corresponds to the maximum wall thickness of 2 mm or less, and the minimum threshold value “0” or more, the minimum wall thickness 0. It corresponds to 5 mm or more.

  When the check box 74 is checked, the number of presence / absence of adjacent voxels calculated for each voxel of the pattern piece is weighted according to the type of contact with the adjacent voxel. For example, the types of contact are weighted so that the weight increases in the order of surface contact, line contact, and point contact. Specifically, when calculating the number of adjacent voxels, the number of adjacent voxels is calculated for each of the surface-contacting voxels, line-contacting voxels, and point-contacting voxels. Then, the number of presence / absence of voxels in surface contact is multiplied by a first coefficient a1, the number of presence / absence of voxels in line contact is multiplied by a second coefficient a2, and the number of presence / absence of voxels in line contact is calculated. The third coefficient a3 is multiplied. Here, a1> a2> a3. As a result, weighting is performed such that the weight increases in the order of surface contact, line contact, and point contact.

  Here, for example, the voxels that make surface contact with the target voxel BX shown in FIG. 21 are the voxels with voxel numbers 5, 11, 13, 14, 16, and 22. Further, the voxels that are in line contact with the target voxel BX are the voxels with voxel numbers 2, 4, 6, 8, 10, 12, 15, 17, 19, 21, 23, and 25. Further, the voxels that make point contact with the target voxel BX are the voxels with voxel numbers 1, 3, 7, 9, 18, 20, 24, and 26. In this case, the number of presence / absence of voxels with surface contact voxel numbers 5, 11, 13, 14, 16, 22 is multiplied by a coefficient a1. Further, the coefficient a2 is multiplied by the number of presence or absence of voxels of voxel numbers 2, 4, 6, 8, 10, 12, 15, 17, 19, 21, 23, 25 that are in line contact with each other. In addition, the number of presence / absence of voxels with voxel numbers 1, 3, 7, 9, 18, 20, 24, and 26 that are in point contact is multiplied by a coefficient a3.

  When the check box 76 is checked, the number of presence / absence of adjacent voxels calculated for each voxel of the pattern piece is weighted with a threshold value based on the connection strength with the adjacent voxel. The connection strength is preset for each voxel of the pattern piece, and the connection strength is preset for each adjacent voxel. In this case, when calculating the number of adjacent voxels, the coefficient is multiplied by the strength of the connection between the adjacent voxels, and the coefficient is decreased by the strength of the connection. As a result, the weighting increases as the connection strength increases.

  In step S218, it is determined whether the cancel button 80 has been pressed. If the cancel button 80 is pressed, the process proceeds to step S220, and if the cancel button 80 is not pressed, the process proceeds to step S222.

  In step S220, the condition input on the setting screen 60 is reset.

  In step S222, it is determined whether to end this routine. For example, it is determined whether or not this routine is ended by determining whether or not the screen closing operation has been performed. Then, if it is determined that the present routine is ended, the present routine is ended, and if it is not determined that the present routine is ended, the process proceeds to step S202.

  As described above, in the present embodiment, for each voxel of the received pattern piece, a three-dimensional threshold matrix is generated by calculating the number of presence / absence of adjacent voxels. As a result, the three-dimensional threshold matrix is generated more efficiently than in the case where the three-dimensional threshold matrix is created one by one by the user's operation.

  Although the present invention has been described above by using each embodiment, the present invention is not limited to the scope described in each embodiment. Various modifications and improvements can be added to the respective embodiments without departing from the scope of the present invention, and the embodiments to which the modifications and improvements are added are also included in the technical scope of the present invention.

  For example, in the present embodiment, a case has been described in which the generation device 10 that generates three-dimensional shape data and the three-dimensional modeling device 100 that models a three-dimensional shape based on the three-dimensional shape data have separate configurations. The modeling apparatus 100 may be configured to have the function of the generation apparatus 10.

  That is, the acquisition unit 110 of the three-dimensional modeling apparatus 100 may acquire the voxel data, and the control unit 112 may execute the generation process of FIG. 6 to generate the three-dimensional shape data.

  Further, for example, the generation processing of the three-dimensional shape data illustrated in FIG. 6 may be realized by hardware such as ASIC (Application Specific Integrated Circuit). In this case, the processing speed can be increased as compared with the case of being realized by software.

  Further, in each of the embodiments, the form in which the program for generating three-dimensional shape data is installed in the storage unit 20 has been described, but the present invention is not limited to this. The three-dimensional shape data generation program according to this embodiment may be provided in a form recorded in a computer-readable storage medium. For example, the program for generating three-dimensional shape data according to the present invention is recorded on an optical disc such as a CD (Compact Disc) -ROM and a DVD (Digital Versatile Disc) -ROM, or a USB (Universal Serial Bus) memory and a memory card. It may be provided in a form recorded in a semiconductor memory such as. Further, the three-dimensional shape data generation program according to the present embodiment may be acquired from an external device via a communication line connected to the communication unit 18.

1 3D modeling system 10 3D shape data generation device 12 controller 14 operation unit 16 display unit 18 communication unit 20 storage unit 32 three-dimensional shape 34 voxel 50 basic shape reception unit 52 generation unit 54 parameter reception unit 56 calculation unit 58 meat Thickness reception section 100 Three-dimensional modeling device

Claims (12)

The presence or absence of modeling of the plurality of voxels from the comparison result of the three-dimensional shape data of the three-dimensional shape represented by a plurality of voxels and the three-dimensional threshold matrix in which the threshold values are arranged in the three-dimensional area corresponding to the basic shape A basic shape receiving unit that receives a basic shape for generating the three-dimensional threshold matrix used when calculating
A generation unit that generates the three-dimensional threshold matrix so that the threshold gradually changes as the distance from the position corresponding to the basic shape increases,
A three-dimensional threshold value matrix generating device. The device for generating a three-dimensional threshold value matrix according to claim 1, wherein the generation unit generates the three-dimensional threshold value matrix so that the threshold value gradually increases from the central portion of the basic shape toward the outer edge portion. The generation unit generates the three-dimensional threshold matrix by calculating the number of adjacent voxels for each voxel of a pattern piece in which a predetermined shape including the basic shape is represented by a plurality of voxels. 2. The three-dimensional threshold value matrix generation device according to 2. A parameter receiving unit that receives a parameter for determining the number of the thresholds of the three-dimensional threshold matrix,
The three-dimensional threshold value matrix generation device according to claim 3, further comprising a calculation unit that calculates the size of the three-dimensional threshold value matrix using the size of the pattern piece and the parameter. A wall thickness receiving portion for receiving the reference wall thickness of the basic shape,
The generating unit generates the three-dimensional threshold matrix by using the number of adjacent voxels for each voxel of the pattern piece corresponding to the reference wall thickness received by the wall thickness receiving unit. Item 3. A three-dimensional threshold value matrix generation device according to item 4. The wall thickness receiving unit receives a plurality of reference wall thicknesses,
The generation unit generates the three-dimensional threshold matrix by integrating thresholds at the same position of the plurality of three-dimensional threshold matrices generated for the plurality of pattern pieces corresponding to each of the plurality of reference wall thicknesses. Item 3. A three-dimensional threshold value matrix generation device according to item 5. The wall thickness receiving portion receives at least one of the minimum wall thickness and the maximum wall thickness,
When the generation unit receives the minimum thickness, the generation unit generates the three-dimensional threshold matrix so that the thickness is not smaller than the minimum thickness, and when the maximum thickness is received, the maximum thickness is received. The device for generating a three-dimensional threshold value matrix according to claim 5 or 6, wherein the three-dimensional threshold value matrix is generated so that the thickness is not larger than the thickness. The said production | generation part weights the number of the presence or absence of the said adjacent voxel calculated about each voxel of the said pattern piece according to the kind of contact with an adjacent voxel. A three-dimensional threshold matrix generator. The three-dimensional threshold matrix generation device according to claim 8, wherein the generation unit weights the types of contact so that the weight increases in the order of surface contact, line contact, and point contact. The three-dimensional threshold matrix according to claim 8 or 9, wherein the generation unit weights the number of presence / absence of the adjacent voxels calculated for each voxel of the pattern piece based on the connection strength with the adjacent voxels. Generator. Using the three-dimensional shape data of the three-dimensional shape represented by a plurality of voxels, and the three-dimensional threshold value matrix generated by the three-dimensional threshold value matrix generating device according to any one of claims 1 to 10. An apparatus for generating three-dimensional shape data, comprising: a calculator that calculates the presence / absence of modeling of the plurality of voxels.   A three-dimensional threshold matrix generation program for causing a computer to function as each unit of the three-dimensional threshold matrix generation device according to claim 1.