Method of manufacturing three-dimensional modeled object, and information processor

Abstract

To provide a manufacturing method that suppresses damage to an appearance of a three-dimensional modeled object.SOLUTION: A manufacturing method comprises: a first step for forming a first contour portion of a first layer on a stage by a nozzle moving from a first start point to a first end point; and a second step for forming a second contour portion by the nozzle moving from a second start point to a second end point. The manufacturing method performs at least one of a first control of controlling so that the first end point is separated from the first start point by a first displacement amount in the first step, a second control of controlling the second start point to a point excluding a first closest point in the second step; and a third control of controlling an internal start point to a point excluding a second closest point in a third step for forming an internal portion of the first layer by the nozzle moving from the internal start point to an internal end point.SELECTED DRAWING: Figure 15

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a three-dimensional object and an information processing device. [Background technology]

[0002] Patent Document 1 describes a method for positioning at least one of the start point and end point of a contour tool path within an internal region when manufacturing a three-dimensional object by forming material layer by layer using a head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2011 / 0070394 Summary of the Invention [Problem to be solved by the invention]

[0004] The positions of the start and end points of a path may affect the appearance of a three-dimensional object. [Means for solving the problem]

[0005] According to a first aspect of the present disclosure, there is provided a three-dimensional printing device that forms a three-dimensional object by stacking layers. This manufacturing method includes a first step of forming a first contour portion of a first layer on the stage by discharging a plasticized material, which is a plasticized material, from a nozzle opening of a nozzle and moving the nozzle relative to a stage along a first contour path, which is a circuitous path, from a first start point to a first end point on the first contour path; and a second step of stacking a second contour portion of a second layer on the first layer by discharging the plasticized material from the nozzle opening and moving the nozzle relative to the stage along a second contour path, which is a circuitous path, from a second start point on the second contour path via at least one second via point to a second end point, wherein: (a) in the first step, a first control is performed to control at least one of the nozzle and the stage so that the first end point is spaced apart from the first starting point by a first deviation amount; and (b) in the second step, a first control is performed to control a virtual second start point, a virtual second end point, and a virtual at least one second via point on the second contour path. (c) a third step performed between the first step and the second step, in which the nozzle is moved relative to the stage along an internal path that makes a circuit inside the first contour path, from an internal starting point on the internal path via at least one internal via point to an internal end point, while discharging the plasticized material from the nozzle opening, thereby forming an internal portion of the first layer inside the first contour portion, wherein the method includes at least one of: (a) a second control that controls at least one of the nozzle and the stage so that a point on the internal path, excluding a second shortest point that is shortest in distance from the first starting point, among a first point group consisting of a tentative internal starting point, a tentative internal end point, and the tentative at least one internal via point, becomes the internal starting point;

[0006] According to a second aspect of the present disclosure, there is provided an information processing device that creates modeling data used in a manufacturing process of a three-dimensional object, which forms a three-dimensional object by stacking layers. The manufacturing process includes: a first step of forming a first contour portion of a first layer on the stage by moving the nozzle relative to the stage along a first contour path, which is a circuitous path, from a first start point to a first end point on the first contour path while plasticizing a material and discharging the plasticized material from a nozzle opening, in accordance with the modeling data; and a second step of stacking a second contour portion of a second layer on the first layer by moving the nozzle relative to the stage along a second contour path, which is a circuitous path, from a second start point to a second end point on the second contour path, via at least one second via point, while discharging the plasticized material from the nozzle opening. The information processing device includes a data generation unit that generates the modeling data and a data output unit that outputs the modeling data. The data generation unit includes: (a) a first creation process in the first process, in which the modeling data is created so that the first end point is spaced apart from the first start point by a first deviation amount; (b) a second creation process in the second process, in which the modeling data is created so that a point on the second contour path, excluding a first shortest point that is the shortest distance from the first start point, among a first point group consisting of the provisional second start point, the provisional second end point, and the provisional at least one second via point on the second contour path, becomes the second start point; and (c) a second creation process that is performed between the first process and the second process, in which the modeling data is created so that the first end point is spaced apart from the first start point by a first deviation amount. If the manufacturing process includes a third step of forming an internal portion of the first layer inside the first contour portion by moving the nozzle relative to the stage along an internal path that is a path that makes a circuit inside the contour path from an internal starting point on the internal path via at least one internal via point to an internal ending point, the manufacturing process performs at least one of the following: a third creation step of creating the modeling data so that the internal starting point is a point on the internal path, excluding a second shortest point among a second point group consisting of a provisional internal starting point, a provisional internal ending point, and the provisional at least one internal via point, which has the shortest distance from the first starting point. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is an explanatory diagram showing a schematic configuration of a three-dimensional printing system. [Figure 2] FIG. 2 is a perspective view showing a schematic configuration of a screw. [Figure 3] Schematic plan view of the barrel. [Figure 4] FIG. 2 is an explanatory diagram schematically illustrating how the three-dimensional printing apparatus prints a model. [Figure 5] FIG. 1 is an explanatory diagram showing a schematic configuration of an information processing apparatus. [Figure 6] 10 is a flowchart of a modeling data generation process. [Figure 7] FIG. 4 is a diagram illustrating path information of modeling data. [Figure 8] FIG. [Figure 9] FIG. 10 is a diagram illustrating the "end point shifting function." [Figure 10] FIG. 10 is a perspective view of a shaped object for explaining the "starting point extraction function." [Figure 11] FIG. 11 is a diagram showing the contour path of the fifth layer of the object shown in FIG. 10 . [Figure 12] FIG. 10 is a diagram illustrating the “next start point shift function” in the layer direction. [Figure 13] 10A and 10B are diagrams illustrating the "next start point shift function" in the surface direction. [Figure 14] 10 is a first flowchart of a modeling data update process. [Figure 15] 10 is a second flowchart of the modeling data update process. [Figure 16] 10 is a flowchart of a forming process. [Figure 17] FIG. 10 is a diagram illustrating a third control. [Figure 18] FIG. 10 is a diagram illustrating a second control. [Figure 19] FIG. 10 is a diagram illustrating the "starting point extraction function." DETAILED DESCRIPTION OF THE INVENTION

[0008] A. Implementation: A1. 3D printing system configuration: FIG. 1 is an explanatory diagram showing a schematic configuration of a three-dimensional printing system 10 according to a first embodiment. Arrows indicating mutually orthogonal X, Y, and Z directions are shown in FIG. 1. The X and Y directions are parallel to a horizontal plane, and the Z direction is a vertically upward direction. The arrows indicating the X, Y, and Z directions are also shown in other figures as appropriate so that the illustrated directions correspond to those in FIG. 1. In the following description, when specifying the direction, positive and negative signs are used in combination to indicate the direction indicated by the arrow in each figure, with "+" indicating the direction indicated by the arrow and "-" indicating the opposite direction. Hereinafter, the +Z direction will also be referred to as "up" and the -Z direction as "down."

[0009] The three-dimensional printing system 10 includes a three-dimensional printing device 100 and an information processing device 400. The three-dimensional printing device 100 of this embodiment is a device that prints a model by a material extrusion method. The three-dimensional printing device 100 includes a control unit 300 for controlling each unit of the three-dimensional printing device 100. The control unit 300 and the information processing device 400 are connected to each other so that they can communicate with each other.

[0010] The three-dimensional modeling apparatus 100 includes a head unit 110 that generates and dispenses a plasticized material, a modeling stage 210 that serves as a base for the model, and a movement mechanism 230 that controls the dispense position of the plasticized material.

[0011] Under the control of the control unit 300, the head unit 110 ejects a plasticized material, which is obtained by plasticizing a solid material, onto the stage 210. The head unit 110 includes a material supply unit 20, which is a supply source of raw materials before being converted into the plasticized material, a plasticizing unit 30, which converts the raw materials into the plasticized material, and an ejection unit 60, which ejects the plasticized material.

[0012] The material supply unit 20 supplies the raw material MR to the plasticizing unit 30. The material supply unit 20 is configured, for example, by a hopper that stores the raw material MR. The material supply unit 20 is connected to the plasticizing unit 30 via a communication passage 22. The raw material MR is fed into the material supply unit 20 in the form of powder or pellets. As the raw material MR, for example, a resin material such as ABS (acrylonitrile butadiene styrene), PEEK (polyether ether ketone), or PP (polypropylene) is used.

[0013] The plasticizing unit 30 plasticizes the raw material MR supplied from the material supply unit 20 to produce a paste-like plasticized material that exhibits fluidity, and then guides the plasticized material to the discharge unit 60. In this embodiment, "plasticization" is a concept that includes melting, and refers to changing a material from a solid to a fluid state. Specifically, for materials that undergo glass transition, plasticization refers to raising the temperature of the material above the glass transition point. For materials that do not undergo glass transition, plasticization refers to raising the temperature of the material above the melting point.

[0014] The plasticizing section 30 includes a screw case 31, a drive motor 32, a screw 40, and a barrel 50. The screw 40 is also called a flat screw, a rotor, or a scroll. The barrel 50 is also called a screw facing portion.

[0015] The screw 40 is housed in a screw case 31. An upper surface 47 of the screw 40 is connected to the drive motor 32, and the screw 40 rotates in the screw case 31 by the rotational driving force generated by the drive motor 32. The drive motor 32 is driven under the control of the control unit 300. Note that the screw 40 may be driven by the drive motor 32 via a reducer.

[0016] 2 is a perspective view showing a schematic configuration of the lower surface 48 side of the screw 40. To facilitate understanding of the technology, the screw 40 shown in FIG. 2 is shown with the positional relationship between the upper surface 47 and the lower surface 48 shown in FIG. 1 reversed in the vertical direction. The screw 40 has a roughly cylindrical shape in which the length in the axial direction, which is the direction along its central axis, is shorter than the length in the direction perpendicular to the axial direction. The screw 40 is positioned so that the rotation axis RX, which is the center of rotation of the screw 40, is parallel to the Z direction.

[0017] A spiral groove 42 is formed on a lower surface 48 of the screw 40, which is a surface that intersects with the rotation axis RX. The communication passage 22 of the material supply section 20 described above communicates with the groove 42 from the side surface of the screw 40. In this embodiment, three grooves 42 are formed, separated by ridges 43. The number of grooves 42 is not limited to three, and may be one, or two or more. The groove 42 is not limited to a spiral shape, and may be a spiral or involute curve shape, or may have a shape that extends in an arc from the center to the outer periphery.

[0018] 1, the lower surface 48 of the screw 40 faces the upper surface 52 of the barrel 50, and a space is formed between the groove 42 of the lower surface 48 of the screw 40 and the upper surface 52 of the barrel 50. Raw material MR is supplied to this space between the screw 40 and the barrel 50 from the material supply section 20 through a material inlet 44 shown in FIG.

[0019] A barrel heater 58 is embedded in the barrel 50 to heat the raw material MR supplied into the groove 42 of the rotating screw 40. A communication hole 56 is provided in the center of the barrel 50.

[0020] 3 is a schematic plan view showing the top surface 52 of the barrel 50. A plurality of guide grooves 54 are formed on the top surface 52 of the barrel 50, and are connected to the communicating holes 56 and extend spirally from the communicating holes 56 toward the outer periphery. Note that one end of the guide grooves 54 does not have to be connected to the communicating holes 56. Also, the guide grooves 54 can be omitted.

[0021] The raw material MR supplied into the groove 42 of the screw 40 is plasticized in the groove 42, flows along the groove 42 due to the rotation of the screw 40, and is guided to the center 46 of the screw 40 as a plasticized material. The paste-like plasticized material that has flowed into the center 46 and exhibits fluidity is supplied to the discharge section 60 via a communication hole 56 provided in the center of the barrel 50. Note that it is not necessary for all types of substances constituting the plasticized material to be plasticized. It is sufficient for the plasticized material to be converted into a state that has fluidity as a whole by plasticizing at least some types of substances constituting the plasticized material.

[0022] The discharge section 60 in Figure 1 includes a nozzle 61 that discharges the plasticized material, a flow path 65 for the plasticized material provided between the screw 40 and the nozzle opening 62, and a discharge control section 77 that controls the discharge of the plasticized material.

[0023] The nozzle 61 is connected to the communication hole 56 of the barrel 50 through a flow path 65. The nozzle 61 discharges the plasticized material produced in the plasticizing section 30 from a nozzle opening 62 at the tip thereof toward the stage 210.

[0024] The discharge control unit 77 includes a discharge amount adjusting mechanism 70 that opens and closes the flow path 65, and a suction mechanism 75 that sucks in the plasticized material and temporarily stores it.

[0025] The discharge rate adjustment mechanism 70 is provided within the flow path 65 and changes the opening of the flow path 65 by rotating within the flow path 65. In this embodiment, the discharge rate adjustment mechanism 70 is configured by a valve. The discharge rate adjustment mechanism 70 is driven by a first drive unit 74 under the control of the control unit 300. The first drive unit 74 is configured by, for example, a stepping motor. The control unit 300 can adjust the flow rate of the plasticizing material flowing from the plasticizing unit 30 to the nozzle 61, i.e., the discharge rate of the plasticizing material discharged from the nozzle 61, by controlling the rotation angle of the valve using the first drive unit 74. The discharge rate adjustment mechanism 70 can adjust the discharge rate of the plasticizing material and can also control the on / off of the outflow of the plasticizing material.

[0026] The suction mechanism 75 includes a branch flow path 66 connected to the flow path 65, and a plunger 67 disposed within the branch flow path 66. The branch flow path 66 is connected to the flow path 65 between the discharge amount adjustment mechanism 70 and the nozzle opening 62. Hereinafter, moving the plunger 67 within the branch flow path 66 away from the flow path 65 will be referred to as "pulling the plunger 67," and moving the plunger 67 closer to the flow path 65 will be referred to as "pushing the plunger 67." The plunger 67 of the suction mechanism 75 is driven by a second drive unit 76 under the control of the control unit 300. The second drive unit 76 is configured, for example, with a stepping motor or a rack-and-pinion mechanism that converts the rotational force of the stepping motor into translational motion of the plunger 67.

[0027] The control unit 300 controls the suction mechanism 75 to pull the plunger 67 when the discharge of the plasticized material from the nozzle 61 stops, thereby temporarily sucking the plasticized material in the flow path 65 into the branch flow path 66. This makes it possible to suppress the tailing phenomenon in which the plasticized material hangs down like a string from the nozzle opening 62.

[0028] The stage 210 is disposed at a position facing the nozzle opening 62 of the nozzle 61. In the first embodiment, the modeling surface 211 of the stage 210 facing the nozzle opening 62 of the nozzle 61 is disposed so as to be parallel to the X and Y directions, i.e., the horizontal direction. The stage 210 is provided with a stage heater 212 for preventing the plasticized material discharged onto the stage 210 from cooling suddenly. The stage heater 212 is controlled by the control unit 300.

[0029] The movement mechanism 230 changes the relative position between the stage 210 and the nozzle 61 under the control of the control unit 300. In this embodiment, the position of the nozzle 61 is fixed, and the movement mechanism 230 moves the stage 210. The movement mechanism 230 is configured by a three-axis positioner that moves the stage 210 in three axial directions, that is, the X, Y, and Z directions, using the driving forces of three motors. In this specification, unless otherwise specified, movement of the nozzle 61 means moving the nozzle 61 and the discharge unit 60 relative to the stage 210. The range of the movement speed of the nozzle 61 by the movement mechanism 230 is set within a predetermined speed range.

[0030] In other embodiments, instead of a configuration in which the moving mechanism 230 moves the stage 210, a configuration in which the moving mechanism 230 moves the nozzle 61 relative to the stage 210 while the position of the stage 210 is fixed may be employed. Alternatively, a configuration in which the moving mechanism 230 moves the stage 210 in the Z direction and moves the nozzle 61 in the X and Y directions, or a configuration in which the moving mechanism 230 moves the stage 210 in the X and Y directions and moves the nozzle 61 in the Z direction may be employed. Even with these configurations, the relative positional relationship between the nozzle 61 and the stage 210 can be changed.

[0031] 1 shows only one head unit 110, the 3D printing apparatus 100 may include multiple head units 110. By including multiple head units 110, different types of plasticizable materials can be ejected from each head unit 110. Therefore, for example, the main body of a model and the support structure that supports the model can be modeled using different types of plasticizable materials.

[0032] The control unit 300 is a control device that controls the overall operation of the 3D printing apparatus 100. The control unit 300 is configured by a computer that includes one or more processors 310, a storage device 320 consisting of a main storage device and an auxiliary storage device, and an input / output interface that inputs and outputs signals to and from the outside. The processor 310 executes a program stored in the storage device 320 to control the plasticizing unit 30 and the movement mechanism 230 in accordance with the printing data acquired from the information processing device 400, thereby printing a printed object on the stage 210. Note that the control unit 300 may be realized by a combination of circuits instead of being configured by a computer.

[0033] FIG. 4 is an explanatory diagram that schematically shows how the three-dimensional printing apparatus 100 prints a model. As described above, in the three-dimensional printing apparatus 100, solid raw material MR is plasticized to generate plasticized material MM. The control unit 300 discharges the plasticized material MM from the nozzle 61 while changing the position of the nozzle 61 relative to the stage 210 in a direction along the printing surface 211 of the stage 210, while maintaining the distance between the printing surface 211 of the stage 210 and the nozzle 61. The plasticized material MM discharged from the nozzle 61 is continuously deposited in the direction of movement of the nozzle 61. The distance between the printing surface 211 of the stage 210 and the nozzle 61 is also referred to as the vertical distance.

[0034] The control unit 300 repeatedly moves the nozzle 61 to form layers ML. After forming one layer ML, the control unit 300 moves the position of the nozzle 61 relative to the stage 210 in the Z direction, which is the stacking direction. Then, a further layer ML is stacked on top of the layer ML that has been formed so far, thereby forming a model.

[0035] The control unit 300 may temporarily suspend the discharge of the plasticizing material from the nozzle 61, for example, when the nozzle 61 moves in the Z direction after completing the formation of one layer ML, or when each layer has multiple independent shaping portions. In this case, the control unit 300 may, for example, close the flow path 65 using the discharge rate adjustment mechanism 70 to stop the discharge of the plasticizing material MM from the nozzle opening 62, and temporarily suck the plasticizing material from the nozzle 61 using the suction mechanism 75. Furthermore, the control unit 300 may, for example, change the position of the nozzle 61, and then resume deposition of the plasticizing material MM from the new nozzle 61 position by opening the flow path 65 using the discharge rate adjustment mechanism 70 while discharging the plasticizing material from the suction mechanism 75.

[0036] 5 is an explanatory diagram showing a schematic configuration of an information processing device 400. The information processing device 400 is configured as a computer in which a CPU 410, a memory 420, a storage device 430, a communication interface 440, and an input / output interface 450 are interconnected via a bus 460. An input device 470 such as a keyboard or a mouse, and a display unit 480 such as a liquid crystal display are connected to the input / output interface 450. The information processing device 400 is connected to the control unit 300 of the three-dimensional printing apparatus 100 via the communication interface 440.

[0037] The CPU 410 executes a data generation program 431 stored in the storage device 430, thereby functioning as a data generation unit 411. The CPU 410 executes a program stored in the storage device 430, thereby functioning as a data output unit 412.

[0038] The data generation unit 411 generates modeling data. The modeling data is data representing information related to the movement path of the nozzle 61 relative to the stage 210, the movement speed of the nozzle 61, the amount of plasticizing material discharged from the nozzle 61, the rotation speed of the screw 40, etc. The data generation unit 411 reads shape data representing the shape of a three-dimensional object created using three-dimensional CAD software or three-dimensional CG software, and divides the shape of the three-dimensional object into layers of a predetermined thickness. Data in STL format, AMF format, etc. is used as the shape data. The data generation unit 411 generates modeling data by determining the movement path of the nozzle 61 and the amount of plasticizing material so that each divided layer is filled with plasticizing material. The modeling data is expressed in G-code, M-code, etc. The data output unit 412 outputs the modeling data to the control unit 300 in response to a request from the control unit 300.

[0039] A2.Modeling data generation process: 6 is a flowchart of the modeling data generation process executed by the data generation unit 411. The modeling data generation process is a process for generating modeling data to be used for modeling a three-dimensional object prior to modeling the three-dimensional object. In step S10, the data generation unit 411 acquires three-dimensional data representing the shape of the three-dimensional object. The data generation unit 411 acquires three-dimensional data such as three-dimensional CAD data from an external source, for example, via a network or a recording medium.

[0040] In step S12, the data generation unit 411 analyzes the three-dimensional data acquired in step S10 and generates layer data by slicing the three-dimensional object into multiple layers along the XY plane. The slicing intervals are set according to the layer pitch.

[0041] In step S14, the data generation unit 411 generates modeling data using the layer data. The modeling data includes path information indicating the movement path of the discharge unit 60, discharge amount information indicating the amount of plasticizing material discharged on each movement path, and control information for controlling the discharge unit 60, the plasticizing unit 30, and the movement mechanism 230. The data generation unit 411 stores the generated modeling data in the memory 420.

[0042] In step S16 as an updating step, the data generating unit 411 performs a shaping data updating process for updating the generated shaping data. The shaping data updating process will be described in detail later.

[0043] Fig. 7 is a diagram illustrating the modeling data and the path information included in the modeling data, and is a schematic diagram of one layer modeled according to the modeling data as viewed in the Z direction.

[0044] The modeling data shown in FIG. 7 includes the modeling layer MLa. The solid line in FIG. 7 indicates the movement path along which the nozzle 61 moves while ejecting the plasticized material from the nozzle opening 62. The dashed line in FIG. 7 indicates the outline of a linear object formed when the nozzle 61 moves along the movement path. The width of the linear object is also referred to as the line width LW. The arrow on the solid line indicates the movement direction of the nozzle 61. A similar notation method is used in the other figures shown below, i.e., the movement path of the nozzle 61 is indicated by a solid line, the outline of the object is indicated by a dashed line, and the movement direction of the nozzle 61 is indicated by an arrow on the solid line.

[0045] The movement path of the modeling layer MLa includes one contour path CR and four internal paths IR. The contour path CR is a path that goes around in one direction. The four internal paths IR include a first internal path IR1, a second internal path IR2, a third internal path IR3, and a fourth internal path IR4. The internal paths IR are arranged inside the contour path CR.

[0046] The contour path CR and the internal path IR are each a line connecting the start point SP and the end point EP. Specifically, the contour path CR is a line connecting the contour start point SPc to the contour end point EPc. The first internal path IR1 is a line connecting the first internal start point SP1 to the first internal end point EP1. The second internal path IR2 is a line connecting the second internal start point SP2 to the second internal end point EP2. The third internal path IR3 is a line connecting the third internal start point SP3 to the third internal end point EP3. The fourth internal path IR4 is a line connecting the fourth internal start point SP4 to the fourth internal end point EP4. When there is no distinction between the contour start point SPc, the first internal start point SP1, the second internal start point SP2, the third internal start point SP3, and the fourth internal start point SP4, they are simply referred to as start points SP. When the contour end point EPc, the first internal end point EP1, the second internal end point EP2, the third internal end point EP3, and the fourth internal end point EP4 are not distinguished from one another, they are also referred to as end points EP. In Fig. 7, the start point SP is indicated by a circle, and the end point EP is indicated by a cross.

[0047] When the "end point shifting function" described below is disabled, the start point SP at which discharge from the nozzle opening 62 starts during the manufacturing process coincides with the start point SP in the path information, and the end point EP at which discharge from the nozzle opening 62 stops coincides with the end point EP in the path information. In the manufacturing process, if the end point EP of the movement path coincides with the start point SP, the shaped object is stabilized. On the other hand, if the end point EP of the movement path coincides with the start point SP, the amount of plasticizing material at the end point EP and the start point SP will be greater than the amount of plasticizing material at positions other than the end point EP and the start point SP. This may result in leakage of plasticizing material at the end point EP and the start point SP. Furthermore, regardless of whether plasticizing material leaks, the end point EP and the start point SP may become visible on the shaped object. In particular, if these positions are aligned in a line, the appearance may be impaired. Furthermore, if the end point EP and the start point SP are aligned in a line, this location is likely to become the starting point of scratches. In particular, in the case of a shaped object having corners, stress is concentrated at the corners, and if the positions of the end point EP and the start point SP are aligned in a line at these corners, these locations are likely to become the starting points of scratches.

[0048] The "end point shift function" is a function that shifts the end point EP from the start point SP. The "next start point shift function" explained next is a function that shapes the start points SP so that they are not aligned in a line, regardless of whether the end point EP and the start point SP coincide with each other.

[0049] A travel route in which the end point EP coincides with the start point SP is also called a "circuit path." For convenience, a circular path may also be called a "circuit path" when the "end point shifting function" is enabled and the end point EP does not coincide with the start point SP. A start point SP in which the end point EP coincides with the start point SP is also called an overlapping point.

[0050] In the path information included in the shaping data generated in step S14 of FIG. 6, the end point EP coincides with the start point SP. Path information defining the contour path CR is also referred to as contour path information. The contour path information of the first layer L1 is also referred to as first contour path information. The contour start point SPc of the contour path information of the first layer L1 is also referred to as the first path start point, and the contour end point EPc of the contour path information of the first layer L1 is also referred to as the first path end point. The contour path information of the second layer L2 is also referred to as second contour path information. The contour start point SPc of the contour path information of the second layer L2 is also referred to as the second path start point, and the contour end point EPc of the contour path information of the second layer L2 is also referred to as the second path end point. Path information defining the internal path IR is also referred to as internal path information. The start point SP of the internal path information is also referred to as the internal path start point, and the end point EP of the internal path information is also referred to as the internal path end point.

[0051] The contour path CR is a path that makes a circuit. The internal path IR is a path that makes a circuit along the contour. A path that makes a circuit along the contour is typically a path in which the shape drawn by this path is similar to the shape drawn by the contour. As an exception, in cases such as when the internal area of ​​the contour is narrow, the path that makes a circuit along the contour may not be a similar shape. Also, in Figure 7, all four internal paths IR make a circuit along the contour, but not all four internal paths IR may make a circuit along the contour. Specifically, only the first internal path IR1 may make a circuit along the contour. Also, not all internal paths IR may make a circuit along the contour. An example of the shape drawn by an internal path IR that does not make a circuit along the contour is a ladder-like shape that turns back at both ends.

[0052] In this disclosure, the internal route IR is a route that makes a circuit along the contour, and therefore, unless otherwise specified, the internal route IR refers to a route that makes a circuit along the contour.

[0053] 8 shows the setting screen IM1 displayed on the display unit 480. When the information processing device 400 receives a command to execute the data generation program 431, the data generation unit 411 causes the display unit 480 to display the setting screen IM1.

[0054] The setting screen IM1 has a first check box IM10, a second check box IM20, and a third check box IM30. The first check box IM10 is a check box for accepting a setting to enable or disable the "end point shifting function." The second check box IM20 is a check box for accepting a setting to enable or disable the "start point extraction function." The third check box IM30 is a check box for accepting a setting to enable or disable the "next start point shifting function." If the user wants to enable each of the "end point shifting function," "start point extraction function," and "next start point shifting function," the user checks the corresponding check box using the input device 470.

[0055] FIG. 9 is a diagram illustrating the "end point shifting function." FIG. 9 shows a contour path CR. As shown in FIG. 9, the "end point shifting function" is a function that shifts the end point EP from the start point SP by a first shift amount SH1 in the manufacturing process. Although FIG. 9 shows the contour path CR as an example, the "end point shifting function" can also be applied to an internal path IR.

[0056] In this embodiment, the data generation unit 411 accepts the first shift amount SH1 as a distance or a magnification of the line width LW. Specifically, the data generation unit 411 accepts the setting of the first shift amount SH1 using a first radio button IM11 and a second radio button IM12 shown in FIG. 8. The first radio button IM11 is a button for accepting the first shift amount SH1 as a distance. When the first radio button IM11 is selected by the user, an input box IM13 is set to an input-enabled state. The input box IM13 accepts input of numbers greater than zero. When the user wants to set the first shift amount SH1 as a distance, the user enters the desired distance in millimeters into the input box IM13.

[0057] The second radio button IM12 is a button for accepting the first shift amount SH1 as a magnification of the line width LW. When the user selects the second radio button IM12, a pull-down menu IM14 is set to an input-enabled state. In this embodiment, the pull-down menu IM14 provides options of 1x the line width LW or 2x the line width LW. When the user wants to set the first shift amount SH1 in terms of the line width LW, the user selects 1x the line width LW or 2x the line width LW in the pull-down menu IM14.

[0058] Fig. 10 is a perspective view of a structure MOa to explain the "starting point extraction function." Fig. 10 shows a structure MOa made up of five layers. The shape of the structure MOa in a plan view from the Z direction is a cross. The first layer L1, second layer L2, third layer L3, fourth layer L4, and fifth layer L5 have the same shape.

[0059] As described above, if overlapping points where the end points EP and start points SP are aligned in a line, the appearance may be marred. If the object MOa has multiple corners and, of the 12 side walls SI parallel to the Z axis, has recessed recesses COa on the four side walls SIa farthest from the center of the object MOa, as shown in Figure 10, if overlapping points are present in these recesses COa, the overlapping points can be made less noticeable. Therefore, the "starting point extraction function" makes it possible to limit the location of the starting point SP to points located in the recesses COa.

[0060] 11 is a diagram showing the contour path CR of the fifth layer L5 of the object MOa shown in FIG. 10. The contour path CR has 11 via points RP in addition to a contour start point SPc and a contour end point EPc. The via points RP include a first via point RP1, a second via point RP2, a third via point RP3, a fourth via point RP4, a fifth via point RP5, a sixth via point RP6, a seventh via point RP7, an eighth via point RP8, a ninth via point RP9, a tenth via point RP10, and an eleventh via point RP11. In the following description, when there is no need to distinguish between the contour start point SPc, the contour end point EPc, and the via points RP, they will simply be referred to as "points PO."

[0061] For each point PO, the angle θ formed by the side walls SI can be calculated. The angle θ is the angle formed by the two side walls SI that form an angle when viewed from outside the object MOa, and more specifically, it is the angle formed by two line segments with the point PO as the base point on the XY plane.

[0062] The angle is calculated as follows: The data generation unit 411 sets one of the points PO as a target point, and calculates the angle between a first line segment connecting the target point and the first point PO2, and a second line segment connecting the target point and the second point PO2, for a first point PO and a second point PO2 that are adjacent to the target point on the movement path among the multiple points PO. In this embodiment, the angle calculated is the angle between the first line segment and the second line segment, which is the angle formed outside the object, i.e., outside the contour drawn by the contour path CR.

[0063] For example, the angle θ of the sixth via point RP6 is the angle between the first line segment connecting the sixth via point RP6 and the fifth via point RP5 and the second line segment connecting the sixth via point RP6 and the seventh via point RP7. For example, the angle θ of the sixth via point RP6 is 90 degrees, and the angle θ of the seventh via point RP7 is 270 degrees.

[0064] When distinguishing between the via points RP on the first layer L1 and the via points RP on the second layer L2, the via points RP on the first layer L1 are also called the first via points, and the via points RP on the second layer L2 are also called the second via points.

[0065] When the second check box IM20 in FIG. 8 is enabled, the input box IM21 is set to an input-enabled state. The user inputs a desired angle into the input box IM21. For example, if "180" degrees is input into the input box IM21, a point where the formed angle θ is smaller than 180 degrees is set as the start point SP. FIG. 11 shows a case where a point that satisfies this condition is set as the contour start point SPc. If, for example, the first via point RP1 shown in FIG. 11 was set as the contour start point SPc in the printing data generated in step S14 shown in FIG. 6, then in the printing data update process shown in FIG. 6, one of the contour start point SPc, the third via point RP3, the sixth via point RP6, and the ninth via point RP9 shown in FIG. 11 is reset as the contour start point SPc.

[0066] FIG. 12 is a diagram illustrating the "next start point shifting function" in the layer direction. The "next start point shifting function" in the layer direction is a function for preventing start points SP from lining up in a line along the stacking direction. FIG. 12 shows a 10-layer model MOb. The shape of the model MOb in a plan view from the Z direction is rectangular. The first layer L1 to the tenth layer L10 have the same shape. In FIG. 12, the position of the contour start point SPc in each layer is indicated by a hatched area. In FIG. 12, if the layer number is "n," the contour start point SPc of the nth layer is represented as "SPc(n)." The same notation is used in the other figures shown below. The bottom layer is the first layer L1, and the top layer is the tenth layer L10.

[0067] As shown in "Disabled" in Fig. 12, when the "next start point shifting function" is disabled, the start points SP of each layer are aligned linearly along the Z direction, which is the stacking direction. In contrast, as shown in "Enabled (Random)" in Fig. 12, when the "next start point shifting function" is enabled, the start points SP of each layer are prevented from aligning linearly in the stacking direction.

[0068] 13 is a diagram illustrating the "next start point shift function" in the plane direction. The "next start point shift function" in the plane direction is a function for preventing the start points SP from lining up in a line along the XY plane, which is the plane direction. Since FIG. 13 is the same as FIG. 7, the same reference numerals as FIG. 7 will be used for the description.

[0069] As shown in "Disabled" in Fig. 13, when the "next start point shift function" in the surface direction is disabled, the start points SP of each movement path are aligned in a line on the same layer. On the other hand, as shown in "Enabled (Random)" in Fig. 13, when the "next start point shift function" is enabled, the start points SP of each movement path are prevented from being aligned in a line along the surface plane on the same layer.

[0070] As shown in FIG. 8, the setting screen IM1 has a third radio button IM31, a fourth radio button IM32, and a fifth radio button IM33 for accepting the application range of the "next start point shift function." The third radio button IM31 is a button that accepts the application range of the "next start point shift function" only in the layer direction. The fourth radio button IM32 is a button that accepts the application range of the "next start point shift function" only in the face direction. The fifth radio button IM33 is a button that accepts the application range of the "next start point shift function" in both the layer direction and the face direction. The user selects one of the third radio button IM31, the fourth radio button IM32, and the fifth radio button IM33.

[0071] The setting screen IM1 has a sixth radio button IM34, a seventh radio button IM35, and an eighth radio button IM36 for accepting a shift setting for the "next start point shift function." The sixth radio button IM34 is a button for accepting the shift setting for the "next start point shift function" as "near the origin." The seventh radio button IM35 is a button for accepting the shift setting for the "next start point shift function" as "shortest distance." The eighth radio button IM36 is a button for accepting the shift setting for the "next start point shift function" as "random."

[0072] When the shift setting of the "next start point shift function" is set to "near the origin," the point PO closest to the origin (0,0,0) of the shape data representing the shape of the three-dimensional object is set as the start point SP. In this case, for example, in the case of a model MOb as shown in FIG. 12, the point PO closest to the origin is a point PO on one side of the model MOb. Therefore, even when the "next start point shift function" is enabled, the start points SP will be arranged in a line. When "near the origin" is set, the calculation load for correcting the modeling data can be reduced.

[0073] When the shift setting of the "next start point shift function" shown in FIG. 8 is set to "shortest distance," the (n+1)th start point SP in the modeling order is set to the point PO that is the shortest distance from the nth start point SP. In the case of a circular pass, the end point EP is a point that coincides with the start point SP or a point that is away from the start point SP by the first shift amount SH1. Therefore, by setting the (n+1)th start point SP to the point PO that is the shortest distance from the nth start point SP, the movement distance of the nozzle 61 can be made the shortest.

[0074] When the shift setting of the "next start point shift function" is set to "shortest distance" and the "next start point shift function" is applied in the surface direction, the (n+1)th start point SP in each layer is set to the point PO that is the shortest distance from the nth start point SP. When the shift setting of the "next start point shift function" is set to "shortest distance" and the "next start point shift function" is applied in the layer direction, the contour start point SPc of the (n+1)th layer is set to the point PO on the contour path CR of the (n+1)th layer that is closest to the start point SP of the last movement path of the nth layer.

[0075] When the shift setting of the "next start point shift function" shown in Fig. 8 is set to "random," the start point SP is set randomly. Specifically, regardless of where the nth start point SP is, the (n+1)th start point SP is randomly selected from multiple points PO on the (n+1)th movement path.

[0076] When the user finishes setting the settings on the setting screen IM1, the user selects the apply button IM40. When the apply button IM40 is selected, the data generation unit 411 stores each setting value in the memory 420. The process in which the data generation unit 411 displays the setting screen IM1 and accepts each setting is called the reception process. In the reception process, if a value is entered in the input box IM13, the data generation unit 411 accepts the entered value as the first deviation amount SH1. In the reception process, if a value is selected in the pull-down menu IM14, the data generation unit 411 accepts the selected value as the first deviation amount SH1. In the reception process, the data generation unit 411 accepts the value entered in IM21 as the reference angle.

[0077] In this embodiment, a setting screen IM1 is used for setting each function. The form for accepting the setting of each function is not limited to a GUI (Graphical User Interface), and other UIs (User Interfaces) may be used.

[0078] 6, the data generation unit 411 generates the shaping data in step S14. In step S16, the data generation unit 411 updates the generated shaping data using the setting values ​​accepted on the setting screen IM1.

[0079] 14 and 15 are flowcharts showing details of the shaping data update process. The data generation unit 411 uses a variable n in the shaping data update process.

[0080] In step S30 as an acquisition process in FIG. 14, the data generation unit 411 acquires the generated modeling data from the memory 420. As described above, the modeling data includes contour path information and internal path information. In this embodiment, the contour path information includes a contour start point SPc, a contour end point EPc, and multiple via points RP. In this embodiment, the internal path information includes a start point SP, an end point EP, and multiple via points RP.

[0081] The contour path information of the first layer L1 is also referred to as first contour path information. The contour start point SPc of the contour path information of the first layer L1 is also referred to as the first path start point, and the contour end point EPc of the contour path information of the first layer L1 is also referred to as the first path end point. The contour path information of the second layer L2 is also referred to as second contour path information. The contour start point SPc of the contour path information of the second layer L2 is also referred to as the second path start point, and the contour end point EPc of the contour path information of the second layer L2 is also referred to as the second path end point. The start point SP of the internal path information is also referred to as the internal path start point, and the end point EP of the internal path information is also referred to as the internal path end point.

[0082] In step S31, the data generation unit 411 refers to the memory 420 and determines whether the "start point extraction function" has been enabled. If it is determined that the "start point extraction function" has been enabled, in step S33, the data generation unit 411 extracts, for each movement path, a point PO whose angle is smaller than the received reference angle, and creates extracted data that associates the extracted point PO with each movement path and stores the extracted data in the memory 420. In detail, the data generation unit 411 calculates the angle between each of the multiple points PO for each movement path as described above. Then, the data generation unit 411 extracts, for each movement path, from the multiple points PO, a point PO whose calculated angle is smaller than the reference angle. If it is determined that the "start point extraction function" has not been enabled, i.e., has been disabled, the data generation unit 411 proceeds to step S35 in FIG. 15.

[0083] 15, the data generation unit 411 sets the n-th layer of the shaping data as the calculation target. Note that in the first step S35 after the start of the shaping data update process, the first layer is set as the calculation target.

[0084] In step S37, the data generation unit 411 refers to the memory 420 and determines whether the "next start point shift function" has been enabled for the surface direction. If it determines that the "next start point shift function" has been enabled, in step S39, the data generation unit 411 updates the latest modeling data for the start points SP of each circular path other than the contour start point SPc of the first layer L1 to modeling data that has been reconfigured according to the settings. Note that the contour start point SPc of the first layer is selected to be the point PO of the contour path CR that is closest to the origin. The end point EP is updated to coincide with the start point SP.

[0085] For example, if "shift setting" is set to "near origin," in step S39, the data generation unit 411 sets the point PO closest to the origin among points PO of one or more pieces of route information on the m-th movement route in the n-th layer as the start point SP of the m-th movement route. The data generation unit 411 performs this setting in order from the second movement route in the n-th layer to the last movement route in the n-th layer.

[0086] For example, if the "shift setting" is set to "shortest distance," in step S39, the data generation unit 411 sets the point PO that is closest to the start point SP of the m-th movement path, among one or more points PO of the route information on the (m+1)-th movement path in the n-th layer, as the start point SP of the (m+1)-th movement path. The data generation unit 411 performs this setting in order from the second movement path in the n-th layer to the last movement path in the n-th layer.

[0087] For example, if "shift setting" is set to "random," in step S39, the data generation unit 411 sets a point PO randomly selected from one or more points PO of the route information on the m-th route in the n-th layer as the start point SP of the m-th route. The data generation unit 411 performs this setting in order from the second route in the n-th layer to the last route in the n-th layer.

[0088] If the extracted data is stored in the memory 420, the data generating unit 411 selects the start point SP from the points PO included in the extracted data in step S39.

[0089] In step S37, if it is determined that the "next start point shift function" for the surface direction is not enabled, that is, that it is disabled, the data generation unit 411 advances the process to step S41.

[0090] In step S41, the data generation unit 411 refers to the memory 420 and determines whether the "next start point shifting function" has been enabled for the layer direction. If it is determined that the "next start point shifting function" has been enabled, in step S43, the data generation unit 411 updates the latest modeling data for the contour start point SPc of the (n+1)th layer to modeling data that has been reconfigured in accordance with the settings. The path end point is updated to coincide with the path start point.

[0091] For example, if the "shift setting" is set to "near origin," in step S43, the data generation unit 411 sets the point PO closest to the origin among the points PO of one or more path information on the contour path CR in the (n+1)th layer as the contour start point SPc in the (n+1)th layer.

[0092] For example, if the "shift setting" is set to "shortest neighbor," in step S43, the data generation unit 411 sets the point PO of one or more path information points PO on the contour path CR in the (n+1)th layer that is closest to the start point SP of the last movement path in the nth layer as the contour start point SPc in the (n+1)th layer.

[0093] For example, if the "shift setting" is set to "random," in step S43, the data generation unit 411 sets a randomly selected point PO from among points PO of one or more path information on the contour path CR in the (n+1)th layer as the contour start point SPc in the (n+1)th layer.

[0094] If the extracted data is stored in the memory 420, the data generating unit 411 selects the start point SP from the points PO included in the extracted data in step S43.

[0095] In step S41, if it is determined that the "next start point shift function" for the layer direction is not enabled, that is, that it is disabled, the data generation unit 411 advances the process to step S45.

[0096] In step S45, the data generation unit 411 determines whether the "end point shifting function" has been enabled by referring to the memory 420. If it is determined that the "end point shifting function" has been enabled, in step S47, the data generation unit 411 updates the latest modeling data for the end points EP of each movement path on the nth layer to modeling data that has been reconfigured in accordance with the settings.

[0097] Specifically, in the case of the contour path CR, the data generating unit 411 updates the contour end point EPc of the contour path information included in the latest shaping data to a point separated from the contour start point SPc by the first deviation amount SH1.

[0098] In detail, in this embodiment, a first updating process is performed in which the path start point of the path information is set to a first start point that is a start point SP in the manufacturing process, and a point that is separated from the path end point of the path information by the received first deviation amount SH1 is set to the first end point that is an end point EP in the manufacturing process, thereby updating the shaping data. Instead of this first updating process, a second updating process may be performed in which the path end point of the path information is set to the first end point that is the end point EP in the manufacturing process, and a point that is separated from the path start point of the path information by the received first deviation amount SH1 is set to the first start point that is the start point SP in the manufacturing process, thereby updating the shaping data.

[0099] If it is determined in step S45 that the "end point shifting function" is not enabled, that is, that the function is disabled, the data generating unit 411 advances the process to step S49.

[0100] In step S49, the data generation unit 411 determines whether or not the processing of step S37 has been performed for all layers of the modeling data. If it is determined in step S49 that the processing of step S37 has not been performed for all layers of the modeling data, the data generation unit 411 increments the variable n in step S51 and returns the processing to step S35. If it is determined in step S49 that the processing of step S37 has been performed for all layers of the modeling data, the data generation unit 411 ends this processing routine. As a result, the settings accepted on the setting screen IM1 are reflected in the modeling data.

[0101] A3.Modeling process: 16 is a flowchart of the formation processing executed by the control unit 300. The manufacturing method is realized by performing this formation processing. The formation processing is a process executed by the control unit 300 using the formation data updated by the formation data update process of FIG.

[0102] In step S61, the control unit 300 acquires the shaping data output from the data output unit 412. The control unit 300 reads the shaping data for one of the multiple layers constituting the three-dimensional object from the acquired shaping data. In this embodiment, the control unit 300 first reads the shaping data for the first layer L1 of the multiple layers constituting the three-dimensional object.

[0103] In step S63 as the first process, the control unit 300 causes the nozzle 61 to move relative to the stage 210 while discharging the plasticizable material from the nozzle opening 62, thereby causing the stage 210 to form a first contour portion, which is the contour portion of the first layer L1. In detail, the control unit 300 causes the nozzle 61 to move relative to the stage 210 along the contour path CR of the first layer L1 from a contour start point SPc on the contour path CR, via a way point RP, to a contour end point EPc, thereby forming the contour portion of the first layer. The start point SP, end point EP, and way point RP of the first contour path, which is the contour path CR of the first layer L1 in the manufacturing process, are also referred to as the first start point, first end point, and first way point, respectively.

[0104] Here, if the "end point shifting function" is set to be valid, a first control is performed in which the contour end point EPc is controlled to a position separated from the contour start point SPc by a first shift amount SH1.

[0105] In step S65 as a third process, the control unit 300 moves the nozzle 61 relative to the stage 210 while discharging the plasticized material from the nozzle opening 62, thereby forming the internal portion of the first layer L1 on the stage 210. In detail, the control unit 300 moves the nozzle 61 relative to the stage 210 along the internal path IR inside the first layer L1 from the start point SP on the internal path IR to the end point EP via the intermediate point RP, thereby forming the internal portion of the first layer L1 inside the contour.

[0106] Here, if the "next start point shift function" is enabled, the "application range" is set to "face direction" or "both directions," and the "shift setting" is set to "random," a third control is performed on at least a portion of the internal path IR. FIG. 17 is a diagram illustrating the third control. As shown in FIG. 17, the third control is a control in which, among the multiple points in the internal path information, a point on the internal path IR, excluding the second shortest point CP2 that is the closest to the contour start point SPc of the same layer, is set as the internal start point, which is the start point SP in the manufacturing process of the internal path IR. This prevents the contour start points SPc of each movement path from being lined up.

[0107] The multiple points of the internal path information specifically refer to the start point SP, end point EP, and one or more via points RP of the internal path information. A point cloud consisting of the start point SP, end point EP, and one or more via points RP of the internal path information is also referred to as a second point cloud. In this embodiment, a point PO of the internal path information included in the shaping data generated in step S14 of FIG. 14 may not coincide with a point PO of the internal path IR in the manufacturing process. Therefore, the start point SP, end point EP, and via point RP included in the internal path information included in the shaping data generated in step S14 of FIG. 14 are also referred to as a tentative internal start point, a tentative internal end point, and a tentative internal via point, respectively. In contrast, the start point SP, end point EP, and via point RP of the internal path IR in the manufacturing process are also referred to as an internal start point, an internal end point, and an internal via point, respectively.

[0108] The contour path CR and first internal path IR1 shown in FIG. 17 are the same as the contour path CR and first internal path IR1 shown in FIG. 7. The contour path CR and first internal path IR1 each have four points PO. The first internal path IR1 has a first point PO1, a second point PO2, a third point PO3, and a fourth point PO4. Of these, the first point PO1 is the second closest point CP2, which is the closest to the contour start point SPc. A point on the internal path IR that is a third deviation amount SH3 away from the second closest point CP2 is set as the internal start point of the manufacturing process. In this embodiment, the third deviation amount SH3 corresponds to the distance between the second closest point CP2 and any point PO on the internal path IR, excluding the second closest point CP2.

[0109] In step S67 of FIG. 16, the control unit 300 determines whether modeling has been completed for all layers included in the modeling data. If it is determined in step S67 that modeling has not been completed for all layers, in step S69, the control unit 300 increments the variable n and returns the process to step S63. This causes modeling of the next layer to be performed. Specifically, when the variable n is changed to "2," in step S63, the nozzle 61 moves relative to the stage 210 along the contour path CR of the second layer L2 from the contour start point SPc to the contour end point EPc on the contour path CR of the second layer L2, thereby forming a second contour portion, which is the contour portion of the second layer L2. This process is also referred to as the second process.

[0110] Here, if the "next start point shifting function" is enabled, the "application range" is set to "layer direction" or "both directions," and the "shift setting" is set to "random," the second control is performed on at least some of the upper layers (the second layer L2 and above). FIG. 18 is a diagram illustrating the second control. As shown in FIG. 18, the second control is a control in which, among the multiple points PO in the contour path information for the second layer L2, a point on the contour path CR of the second layer L2, excluding the first shortest point CP1 that is the closest to the contour start point SPc(1) of the first layer L1, is set as the second start point, which is the start point SP of the contour path CR in the manufacturing process. This prevents the contour start points SPc of each layer from lining up in the stacking direction.

[0111] The multiple points of the contour path information specifically refer to the start point SP, end point EP, and one or more via points RP of the contour path information. A point cloud consisting of the start point SP, end point EP, and one or more via points RP of the contour path information of the second layer L2 is also referred to as the first point cloud. In this embodiment, point PO of the contour path information included in the shaping data generated in step S14 of FIG. 14 may not coincide with point PO in the manufacturing process. Therefore, the contour start point SPc, contour end point EPc, and via point RP included in the contour path information of the second layer L2 included in the shaping data generated in step S14 of FIG. 14 are also referred to as the tentative second start point, tentative second end point, and tentative second via point, respectively. In contrast, the start point SP, end point EP, and via point RP of the second contour path, which is the contour path CR of the second layer L2 in the manufacturing process, are also referred to as the second start point, second end point, and second via point, respectively.

[0112] The contour start point SPc(1) of the first layer and the contour start point SPc(2) of the second layer shown in FIG. 18 are the same as the contour start point SPc(1) of the first layer and the contour start point SPc(2) of the second layer shown in FIG. 12. The contour path CR(1) of the first layer and the contour path CR(2) of the second layer each have four points PO. The contour path CR(2) of the second layer has a first point PO1, a second point PO2, a third point PO3, and a fourth point PO4. Of these, the first point PO1 is the first closest point CP1, which is the shortest distance from the contour start point SPc(1) of the first layer L1. A point on the contour path CR of the second layer L2 that is separated from the first closest point CP1 by a second deviation amount SH2 is set as the second start point. In this embodiment, the second deviation amount SH2 corresponds to the distance between the first closest point CP1 and any point PO on the contour path CR of the second layer L2, excluding the first closest point CP1.

[0113] In step S67 of FIG. 16, if it is determined that modeling has been completed for all layers, the control unit 300 ends this processing routine.

[0114] The "start point extraction function" will be explained further using FIG. 19. FIG. 19 is a diagram illustrating the "start point extraction function." As described above, the "start point extraction function" and the "next start point shifting function" are set independently of each other. The "disabled" diagram in FIG. 19 illustrates the position of the contour start point SPc of each layer when the "next start point shifting function" is enabled and the "start point extraction function" is disabled in the layer direction. The "enabled" diagram in FIG. 19 illustrates the position of the contour start point SPc of each layer when the "next start point shifting function" is enabled and the "start point extraction function" is enabled in the layer direction. Specifically, the "start point extraction function" being enabled refers to the case where a point PO with an angle of less than 180 degrees is extracted. As shown in FIG. 19, when the "start point extraction function" is enabled, the contour start point SPc is selected from the points PO with an angle of less than 180 degrees. Therefore, the contour start point SPc of each layer except the first layer L1 is located at the recess COa.

[0115] The contour start point SPc of the first layer L1 is also referred to as the first start point, and the contour end point EPc of the first layer L1 is also referred to as the first end point. The contour start point SPc of the second layer L2 is also referred to as the second start point, and the contour end point EPc of the second layer L2 is also referred to as the second end point. Step S39 is also referred to as the third creation step, step S43 is also referred to as the second creation step, and step S47 is also referred to as the first creation step.

[0116] According to the embodiment described above, the manufacturing process includes a first step, a second step, and a third step. In the first step, the nozzle 61 moves along the contour path CR of the first layer L1 while discharging the plasticized material from the nozzle opening 62, thereby forming the contour portion of the first layer L1. In the third step, the nozzle 61 moves along the internal path IR of the first layer L1, thereby forming the internal portion of the first layer L1. In the second step, the nozzle 61 moves along the contour path CR of the second layer L2, thereby forming the contour portion of the second layer L2.

[0117] If the user has enabled the "end point shifting function," a first control is performed in the first step, in which the stage 210 is controlled to shift the contour end point EPc from the contour start point SPc by a first shift amount SH1. If the user has enabled the "next start point shifting function" for the surface direction, a third control is performed in the third step, in which the start point SP of the internal path IR is shifted by a third shift amount SH3 with respect to the second closest point CP2, which is the closest point to the contour start point SPc of the first layer L1. If the user has enabled the "next start point shifting function" for the stacking direction, a second control is performed in the second step, in which the stage 210 is controlled to shift the contour start point SPc of the second layer L2 by a second shift amount SH2 with respect to the first closest point CP1, which is the closest point to the contour start point SPc of the first layer L1. This prevents at least one of the following problems from occurring: impairing the appearance due to the end point EP coinciding with the start point SP; and impairing the appearance due to overlapping points where the end point EP and the start point SP coincide with each other and lining up. Furthermore, when overlapping points are prevented from lining up, it is possible to prevent a decrease in the strength of the shaped object.

[0118] In addition, in the receiving step, the data generation unit 411 displays a setting screen IM1 and receives the first deviation amount SH1. In step S30, the data generation unit 411 acquires shaping data including information on the contour path CR of the first layer L1, which is defined by a line connecting the contour start point SPc and the contour end point EPc. Then, in step S47, the data generation unit 411 updates the shaping data to include information on the contour path CR of the first layer L1, which separates the contour end point EPc from the contour start point SPc by the first deviation amount SH1. This allows the user to set the contour end point EPc to a point that is the desired first deviation amount SH1 away.

[0119] Furthermore, in the receiving step, the data generation unit 411 displays the setting screen IM1 and receives the reference angle. If the "start point extraction function" is enabled, the "next start point shift function" is enabled for the layer direction, and the shift setting is "shortest distance," the data generation unit 411 sets, in step S41, the point with the shortest distance from the end point EP of the last movement path of the nth layer among multiple points PO included in the contour path CR of the (n+1)th layer, whose angle θ is smaller than the reference angle, as the contour start point SPc of the (n+1)th layer. This allows the user to set, as the contour start point SPc of the (n+1)th layer, a point with an angle θ smaller than the desired reference angle and a short movement distance of the nozzle 61. This makes it possible to prevent damage to the appearance of the model and shorten the process time required for modeling.

[0120] Furthermore, the internal path IR includes multiple points PO, and the third deviation amount SH3 is equal to the deviation amount between a point PO other than the second closest point CP2 and the second closest point CP2 among the multiple points PO. This makes it possible to set any of the multiple points PO previously included in the internal path IR as the updated start point SP. Therefore, the calculation load required for updating the shaping data can be reduced. Furthermore, the contour path CR of the second layer L2 includes multiple points PO, and the second deviation amount SH2 is equal to the deviation amount between a point PO other than the first closest point CP1 and the first closest point CP1 among the multiple points PO. This makes it possible to set any of the multiple points PO previously included in the contour path CR as the updated start point SP. Therefore, the calculation load required for updating the shaping data can be reduced.

[0121] Furthermore, when the "end point shift function" is enabled on the setting screen IM1 and the first shift amount SH1 is set to the line width LW, the first shift amount SH1 can be set to an appropriate amount so that the amount of plasticized material at the contour start point SPc is not excessively large and no gap is created between the contour start point SPc and the contour end point EPc.

[0122] In the above embodiment, the first control to the third control are described using the first layer L1 and the second layer L2 as examples, but the layers to which the first control to the third control are applied are not limited to the first layer L1 and the second layer L2. The first control to the third control can be applied to any two layers among multiple layers.

[0123] B. Other Embodiments: (B1) In the above embodiment, the point PO closest to the origin is set as the contour start point SPc of the first layer L1. As another example, when the "start point extraction function" is enabled, in step S37 as the updating step, a point PO that is included in the contour path CR of the first layer L1 and whose angle θ is smaller than the reference angle may be set as the contour start point SPc of the first layer L1. This can further prevent the appearance of the model from being impaired.

[0124] (B2) In the above embodiment, when the "next start point shifting function" is enabled, one of the multiple points PO included in the path information is set as the start point SP. As another embodiment, a point on each path other than the multiple points PO included in the path information may be set as the start point SP. Specifically, the second shift amount SH2 may be set to an arbitrary distance, similar to the first shift amount SH1. This increases the degree of freedom of the start point SP of the contour path CR of the second layer L2. Furthermore, the third shift amount SH3 may be set to an arbitrary distance, similar to the first shift amount SH1. This increases the degree of freedom of the start point of the internal path IR.

[0125] C. Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features of the embodiments corresponding to the technical features in each aspect described below can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0126] (1) According to a first aspect of the present disclosure, there is provided a method for manufacturing a three-dimensional object, which forms the three-dimensional object by stacking layers. This manufacturing method includes a first step of forming a first contour portion of a first layer on the stage by discharging a plasticized material, which is a plasticized material, from a nozzle opening of a nozzle and moving the nozzle relative to a stage along a first contour path, which is a circuitous path, from a first start point to a first end point on the first contour path; and a second step of stacking a second contour portion of a second layer on the first layer by discharging the plasticized material from the nozzle opening and moving the nozzle relative to the stage along a second contour path, which is a circuitous path, from a second start point on the second contour path via at least one second via point to a second end point, wherein: (a) in the first step, a first control is performed to control at least one of the nozzle and the stage so that the first end point is spaced apart from the first starting point by a first deviation amount; and (b) in the second step, a first control is performed to control a virtual second start point, a virtual second end point, and a virtual at least one second via point on the second contour path. (c) a third step performed between the first step and the second step, in which the nozzle is moved relative to the stage along an internal path that makes a circuit inside the first contour path, from an internal starting point on the internal path via at least one internal via point to an internal end point, while discharging the plasticized material from the nozzle opening, thereby forming an internal portion of the first layer inside the first contour portion, wherein the method includes at least one of: (a) a second control that controls at least one of the nozzle and the stage so that a point on the internal path, excluding a second shortest point that is shortest in distance from the first starting point, among a first point group consisting of a tentative internal starting point, a tentative internal end point, and the tentative at least one internal via point, becomes the internal starting point; According to this embodiment, at least one of the following is suppressed: the deterioration of the appearance caused by the end point coinciding with the start point, and the deterioration of the appearance caused by overlapping points whose end points coincide with the start point being arranged in a line.

[0127] (2) In the above aspect, the method may further include: a receiving step of receiving the first deviation amount; an acquiring step of acquiring first contour path information that defines the first contour path with a line connecting a first path start point as a temporary first start point and a first path end point as a temporary first end point, the first path end point coinciding with the first path start point; a first updating step of setting the first path start point to the first start point and updating the modeling data by setting a point on the first contour path that is away from the first path end point by the received first deviation amount as the first end point; or a second updating step of setting the first path end point to the first end point and updating the modeling data by setting a point on the first contour path that is away from the first path start point by the received first deviation amount as the first start point;

[0128] (3) In the above aspect, the method further comprises: an acquiring step of acquiring printing data including second contour path information that defines the second contour path with a line connecting a second path start point as the provisional second start point and a second path end point as the provisional second end point; and an updating step of updating the printing data by setting a point on the second contour path that is away from the first closest point by a second deviation amount as the second start point, wherein the second step may be performed in accordance with the updated printing data. According to this aspect, by updating the created printing data, it is possible to create printing data in which a point that is away from the first closest point by the second deviation amount is set as the second start point.

[0129] (4) In the above aspect, the method further comprises: an acquiring step of acquiring shaping data including internal path information that defines the internal path with a line connecting an internal path start point as the temporary internal start point and an internal path end point as the temporary internal end point; and an updating step of updating the shaping data by setting a point on the internal path that is away from the second nearest point by a third deviation amount as the internal start point, wherein the third step may be performed in accordance with the updated shaping data. According to this aspect, by updating the created shaping data, it is possible to create shaping data in which a point that is away from the second nearest point by the third deviation amount is set as the internal start point.

[0130] (5) In the above aspect, the method further comprises an acquisition step of acquiring shaping data including first contour path information that defines the first contour path with a line connecting a first path start point as a tentative first start point and a first path end point as a tentative first end point, the first contour path information being such that the first path end point coincides with the first contour path start point, the first contour path information including a plurality of first via points, one of which is a target point and which is adjacent to the target point on the first contour path among the plurality of points, The method may further include a receiving step of receiving a reference angle for an angle between a first line segment connecting a first point and a second point, the first line segment connecting the target point and the first point, and a second line segment connecting the target point and the second point, the reference angle being an angle on the outside of the first contour portion; and an updating step of calculating the angle for each of the plurality of points, setting a point among the plurality of points at which the calculated angle is smaller than the reference angle as the first start point, and updating the shaping data, wherein the first step may be performed according to the updated shaping data. According to this embodiment, the reference angle is set to an angle of 180 degrees or less, and when the shaped object has a recessed portion with a corner whose angle is smaller than the reference angle, the first start point can be placed in the recessed portion. This further prevents damage to the appearance of the shaped object. The user can set a desired angle in the receiving step.

[0131] (6) In the above-described embodiment, the method further comprises an acquisition step of acquiring shaping data including second contour path information that defines the second contour path with a line connecting a second path start point as the provisional second start point and a second path end point as the provisional second end point, the second path end point coinciding with the second path start point, and the second contour path information includes: a target point being one of a plurality of points consisting of the second path start point and the at least one second via point; and a first point and a second point being points adjacent to the target point on the second contour path among the plurality of points; The method may further include a receiving step of receiving a reference angle for the angle formed by a first line segment connecting the target point and the first point and a second line segment connecting the target point and the second point, the reference angle being on the outside of the second contour portion; and an updating step of calculating the angle for each of the plurality of points, and setting the point among the plurality of points where the calculated angle is smaller than the reference angle and is the shortest distance from the internal end point as the second start point, thereby updating the printing data. The second step may be performed according to the updated printing data. According to this embodiment, if the object has a recess, the second start point can be placed in the recess, thereby further preventing damage to the appearance of the object. In addition, a route with a short nozzle movement time is selected, thereby shortening the time required for printing. The user can set a desired angle in the receiving step.

[0132] (7) In the above-described embodiment, the second deviation amount may be equal to the deviation amount between a point in the first point group that is different from the first closest point and the first closest point. According to this embodiment, one of a plurality of points that are included in the second contour path in advance can be set as the updated second start point. Therefore, the calculation load required for updating the modeling data can be reduced.

[0133] (8) In the above-described embodiment, the third deviation amount may be equal to the deviation amount between a point in the second point group that is different from the second closest point and the second closest point. According to this embodiment, one of a plurality of points that are included in the internal path in advance can be set as the updated internal start point. Therefore, the calculation load required for updating the modeling data can be reduced.

[0134] (9) In the above embodiment, the first deviation amount may be an amount based on the line width of the plasticized material discharged from the nozzle opening. According to this embodiment, the first deviation amount can be set based on the line width. The amount of plasticized material discharged is adjusted according to the line width. Therefore, by setting the first deviation amount based on the line width, it is possible to set an appropriate deviation amount so that the amount of plasticized material at the first starting point is not excessively large and no gap is formed between the first starting point and the first ending point.

[0135] (10) According to a second aspect of the present disclosure, there is provided an information processing device that creates modeling data used in a manufacturing process of a three-dimensional object, which forms a three-dimensional object by stacking layers. The manufacturing process includes: a first step of forming a first contour portion of a first layer on the stage by moving the nozzle relative to the stage along a first contour path, which is a circuitous path, from a first start point to a first end point on the first contour path, while discharging a plasticized material obtained by plasticizing a material from a nozzle opening of the nozzle, in accordance with the modeling data; and a second step of stacking a second contour portion of a second layer on the first layer by moving the nozzle relative to the stage along a second contour path, which is a circuitous path, from a second start point to a second end point on the second contour path, via at least one second via point, while discharging the plasticized material from the nozzle opening. The information processing device includes a data generation unit that generates the modeling data and a data output unit that outputs the modeling data, and the data generation unit performs the following steps: (a) a first creation step in the first step, in which the modeling data is created so that the first end point is spaced apart from the first start point by a first deviation amount; (b) a second creation step in the second step, in which the modeling data is created so that a point on the second contour path, excluding a first shortest point that is shortest in distance from the first start point among a first point group consisting of a provisional second start point, a provisional second end point, and the at least one provisional second via point on the second contour path, becomes the second start point; and (c) a second creation step that is performed between the first step and the second step, in which the data generation unit performs the following steps: If the manufacturing process includes a third step of forming an internal portion of the first layer inside the first contour portion by ejecting the plasticized material from the nozzle opening and moving the nozzle relative to the stage along an internal path that is a path that makes a circuit inside the first contour path from an internal starting point on the internal path via at least one internal via point to an internal ending point, the manufacturing process also includes at least one of the following: a third creation step of creating the modeling data so that the internal starting point is a point on the internal path, excluding a second shortest point among a second point group consisting of a provisional internal starting point, a provisional internal ending point, and the provisional at least one internal via point, which is shortest in distance from the first starting point.According to this embodiment, for a three-dimensional object manufactured in accordance with the modeling data, at least one of the following is suppressed: deterioration of the appearance caused by the end point coinciding with the start point, and deterioration of the appearance caused by overlapping points whose end points coincide with the start point being arranged in a line.

[0136] The present disclosure is not limited to the above-described method for manufacturing three-dimensional objects, but can be realized in various forms, such as a three-dimensional object manufacturing device, a three-dimensional object manufacturing system, a computer program, and a non-transitory tangible recording medium on which a computer program is recorded in a computer-readable manner. [Explanation of symbols]

[0137] 10...three-dimensional modeling system, 20...material supply section, 22...communicating passage, 30...plasticizing section, 31...screw case, 32...drive motor, 40...screw, 42...groove section, 43...ridge section, 44...material inlet, 46...center section, 47...upper surface, 48...lower surface, 50...barrel, 52...upper surface, 54...guide groove, 56...communicating hole, 58...barrel heater, 60...discharge section, 61...nozzle, 62...nozzle opening, 65...flow path, 66...branched flow path, 67...plunger, 70...discharge amount adjustment mechanism, 74...first drive section, 75...suction mechanism, 76...second drive section, 77...discharge control section, 100...three-dimensional modeling device, 110...head section, 210...stage, 211...Building surface, 212...Stage heater, 230...Moving mechanism, 300...Control unit, 310...Processor, 320...Storage device, 400...Information processing device, 410...CPU, 411...Data generation unit, 412...Data output unit, 420...Memory, 430...Storage device, 431...Data generation program, 440...Communication interface, 450...Input / output interface, 460...Bus, 470...Input device, 480...Display unit, CR...Contour path, IM1...Setting screen, IR...Internal path, LW...Line width, MM...Plasticized material, MR...Raw material, RX...Rotation axis, SH1...First deviation amount, SH2...Second deviation amount, SH3...Third deviation amount

Claims

1. A method for manufacturing a three-dimensional object, which forms a three-dimensional object by stacking layers, comprising: a first step of forming a first contour portion of a first layer on the stage by discharging a plasticized material obtained by plasticizing a material from a nozzle opening of a nozzle and moving the nozzle relative to the stage along a first contour path, which is a circular path, from a first start point to a first end point on the first contour path; a second step of discharging the plasticized material from the nozzle opening while moving the nozzle relative to the stage along a second contour path, which is a circuitous path, from a second start point on the second contour path via at least one second via point to a second end point, thereby laminating a second contour portion of the second layer on the first layer; (a) in the first step, a first control for controlling at least one of the nozzle and the stage so that the first end point is spaced apart from the first start point by a first deviation amount; (b) in the second step, a second control for controlling at least one of the nozzle and the stage so that a point on the second contour path, excluding a first closest point having the shortest distance from the first start point, among a first point group consisting of the provisional second start point, the provisional second end point, and the provisional at least one second via point on the second contour path, becomes the second start point; (c) when the method includes a third step, which is performed between the first step and the second step, of forming an internal portion of the first layer inside the first contour portion by discharging the plasticized material from the nozzle opening while moving the nozzle relative to the stage along an internal path that is a path that makes a full circuit inside the first contour path, from an internal starting point on the internal path to an internal ending point via at least one internal via point, and discharging the plasticized material from the nozzle opening, the method includes at least one of a third control step of controlling at least one of the nozzle and the stage so that the internal starting point is a point on the internal path excluding a second shortest point that is shortest in distance from the first starting point among a second point group consisting of the tentative internal starting point, the tentative internal ending point, and the tentative at least one internal via point.

2. The method for manufacturing a three-dimensional object according to claim 1, a receiving step of receiving the first deviation amount; an acquiring process for acquiring shaping data including first contour path information that defines the first contour path by a line connecting a first path start point as a tentative first start point and a first path end point as a tentative first end point, the first path end point coinciding with the first path start point; a first updating step of setting the first path starting point to the first start point, and setting a point on the first contour path that is away from the first path end point by the received first deviation amount to the first end point, thereby updating the modeling data; or a second updating step of setting the first path end point to the first end point, and setting a point on the first contour path that is away from the first path starting point by the received first deviation amount to the first start point, thereby updating the modeling data; The first step is performed in accordance with the updated modeling data.

3. The method for manufacturing a three-dimensional object according to claim 1, an acquiring process of acquiring shaping data including second contour path information that defines the second contour path by a line connecting a second path start point as the tentative second start point and a second path end point as the tentative second end point; an updating step of setting a point on the second contour path that is away from the first closest point by a second deviation amount as the second start point, and updating the modeling data; The second step is performed in accordance with the updated modeling data.

4. The method for manufacturing a three-dimensional object according to claim 1, an acquisition process of acquiring shaping data including internal path information that defines the internal path by a line connecting an internal path start point as the tentative internal start point and an internal path end point as the tentative internal end point; an updating step of setting a point on the internal path that is away from the second closest point by a third deviation amount as the internal start point, and updating the modeling data; The third step is performed in accordance with the updated modeling data.

5. The method for manufacturing a three-dimensional object according to claim 1, an acquiring step of acquiring shaping data including first contour path information that defines the first contour path by a line connecting a first path start point as a tentative first start point and a first path end point as a tentative first end point, the first contour path information being the first contour path information in which the first path end point coincides with the first path start point; the first contour route information includes a plurality of first waypoints; a receiving step of receiving a reference angle for an angle formed by a first line segment connecting the target point and the first point and a second line segment connecting the target point and the second point, the angle being on the outside of the first contour portion, for a first point and a second point that are adjacent to the target point on the first contour path among the plurality of points, the first point being a target point and a second point being adjacent to the target point on the first contour path; an updating step of calculating the angle for each of the plurality of points, and setting a point among the plurality of points at which the calculated angle is smaller than the reference angle as the first start point, and updating the modeling data; The first step is performed in accordance with the updated modeling data.

6. The method for manufacturing a three-dimensional object according to claim 1, an acquiring step of acquiring shaping data including second contour path information that defines the second contour path by a line connecting a second path start point as the tentative second start point and a second path end point as the tentative second end point, and the second path end point coincides with the second path start point; a receiving step of receiving a reference angle for an angle formed by a first line segment connecting the target point and the first point and a second line segment connecting the target point and the second point, the angle being on the outside of the second contour portion, for a first point and a second point that are adjacent to the target point on the second contour path among the plurality of points, the first point and the second point being adjacent to the target point on the second contour path; an updating step of calculating the angle between each of the plurality of points, and setting a point among the plurality of points at which the calculated angle is smaller than the reference angle and which is the shortest distance from the internal end point as the second start point, thereby updating the modeling data, The second step is performed in accordance with the updated modeling data.

7. The method for manufacturing a three-dimensional object according to claim 3, the second deviation amount is equal to the deviation amount between a point in the first point group that is different from the first closest point and the first closest point.

8. The method for manufacturing a three-dimensional object according to claim 4, the third deviation amount is equal to the deviation amount between a point in the second point group that is different from the second closest point and the second closest point.

9. The method for manufacturing a three-dimensional object according to claim 1, The method for manufacturing a three-dimensional object, wherein the first deviation amount is an amount based on a line width of the plasticized material discharged from the nozzle opening.

10. An information processing device that creates modeling data used in a manufacturing process of a three-dimensional object, in which the three-dimensional object is formed by stacking layers, The manufacturing process includes: a first step of forming a first contour portion of a first layer on the stage by moving the nozzle relative to the stage along a first contour path, which is a path that makes a full circle while plasticizing a material and discharging the plasticized material from a nozzle opening of the nozzle, from a first start point to a first end point on the first contour path; a second step of discharging the plasticized material from the nozzle opening while moving the nozzle relative to the stage along a second contour path, which is a circuitous path, from a second start point on the second contour path via at least one second via point to a second end point, thereby laminating a second contour portion of the second layer on the first layer; The information processing device includes: a data generation unit that generates the modeling data; a data output unit that outputs the modeling data, The data generation unit (a) a first creation step of creating the shaping data such that the first end point is spaced apart from the first start point by a first deviation amount in the first step; (b) a second creation step of creating the modeling data in the second step so that a point on the second contour path, excluding a first closest point having the shortest distance from the first start point, among a first point group consisting of the provisional second start point, the provisional second end point, and the provisional at least one second via point on the second contour path, becomes the second start point; (c) When the manufacturing process includes a third process, which is performed between the first process and the second process, in which the nozzle is moved relative to the stage along an internal path that is a path that makes a circuit inside the first contour path while ejecting the plasticized material from the nozzle opening, from an internal starting point on the internal path to an internal ending point via at least one internal via point, thereby forming an internal portion of the first layer inside the first contour portion, the information processing device performs at least one of the following: a third creation process in which the information processing device creates the modeling data so that a point on the internal path, excluding a second shortest point that is shortest in distance from the first starting point among a second point group consisting of a provisional internal starting point, a provisional internal ending point, and the provisional at least one internal via point, becomes the internal starting point.

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