Control information modification method, control information modification device, and program

Abstract

To provide a control information correction method, control information correction device and program which can suppress a topical deviation of a laminate height to realize a high-quality molding article's molding when molding a molding article by laminate molding.SOLUTION: A control information correction method includes: a molding information acquisition step for acquiring molding information on the molding route, laminate direction and laminate condition of a weld bead B which forms a bead layer BL; a predicted shape calculation step for calculating a predicted shape of the bead layer BL on the basis of the molding information; a change necessity determination step for determining whether or not the laminate condition needs to be changed on the basis of the predicted shape; and a laminate condition adjustment step for adjusting the laminate condition of the weld bead B for each place when it is determined that the laminate condition needs to be changed, to suppress a dispersion of the laminate height BLh of the bead layer BL.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to a control information modifying method, a control information modifying device, and a program. [Background technology]

[0002] In recent years, there has been a growing need for 3D printers as a means of production, and research and development is being conducted in the aircraft industry, etc., with a view to practical application of 3D printers to metal materials in particular. 3D printers that use metal materials use a heat source such as a laser or arc to melt metal powder or metal wire, and then layer the molten metal to create an object.

[0003] Patent Document 1 discloses a molding device that, when stacking a second weld bead on a first weld bead, calculates a parameter value that controls the amount of droplets discharged from a welding torch based on the amount of deviation from the center line, and controls the welding torch and movement mechanism based on the calculated parameter value, thereby reducing errors in the vertical direction and the collapse of the three-dimensional shape. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-160217 Summary of the Invention [Problem to be solved by the invention]

[0005] In additive manufacturing, in which an object is created by stacking weld beads, when the object is created based on a trajectory plan designed by slicing the shape of the object represented by three-dimensional CAD data into multiple layers, the target position set in the trajectory plan may deviate from the actual shape.

[0006] In this way, if a mismatch occurs between the target position of the trajectory plan and the actual shape, the torch may interfere with the object being created, or the distance between the object and the torch may become too large, causing an arc start error and hindering the continuation of the creation.

[0007] Therefore, an object of the present invention is to provide a control information correction method, a control information correction device, and a program that can suppress local deviations in stack height when creating a model by additive manufacturing, thereby realizing the creation of a high-quality model. [Means for solving the problem]

[0008] The present invention comprises the following configurations. (1) A control information correction method for correcting control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers are stacked, the bead layers being obtained by dividing a target shape into multiple layers, the method comprising: a forming information acquisition process for acquiring forming information regarding a forming path, a layering direction, and layering conditions of the weld bead that forms the bead layer; a predicted shape calculation step of calculating a predicted shape of the bead layer based on the shaping information; a change necessity determination step of determining whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjusting step of adjusting the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer when it is determined that the lamination conditions need to be changed; Including, Control information modification method. (2) A control information correction device that corrects control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers obtained by dividing a target shape into multiple layers are stacked, the control information correction device comprising: a forming information acquisition unit that acquires forming information regarding a forming path, a layering direction, and layering conditions of the weld bead that forms the bead layer; a predicted shape calculation unit that calculates a predicted shape of the bead layer based on the shaping information; a change necessity determination unit that determines whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjusting unit that adjusts the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer when it is determined that the lamination conditions need to be changed; Including, Control information modification device. (3) A program for correcting control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers are stacked, the bead layers being obtained by dividing a target shape into multiple layers, the program comprising: On the computer, a forming information acquisition function for acquiring forming information regarding a forming path, a lamination direction, and lamination conditions of the weld bead that forms the bead layer; a predicted shape calculation function for calculating a predicted shape of the bead layer based on the shaping information; a change necessity determination function that determines whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjustment function that, when it is determined that the lamination conditions need to be changed, adjusts the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer; In order to realize this, program. [Effects of the Invention]

[0009] According to the present invention, when manufacturing an object by additive manufacturing, it is possible to suppress local deviations in stack height and realize the manufacturing of a high-quality object. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing the overall configuration of an additive manufacturing system. [Figure 2] FIG. 2 is a functional block diagram of the control information modifying device. [Figure 3]FIG. 3 is a flowchart showing a procedure for modifying control information by the control information modifying device. [Figure 4] FIG. 4 is an explanatory diagram showing an example of a model that takes into consideration overlap between adjacent beads. [Figure 5] FIG. 5 is an explanatory diagram showing an example of a model that reproduces the shape of weld metal dripping down to the lower layer side. [Figure 6] FIG. 6 is a schematic perspective view of a cylindrical object having a conical shape. [Figure 7] FIG. 7 is a schematic diagram showing a predicted shape of a cylindrical object having a conical shape. [Figure 8] FIG. 8 is a schematic diagram showing deviations in the layer height of bead layers that occur when weld beads are stacked. [Figure 9] FIG. 9 is a schematic diagram illustrating the deviation in layer height of the bead layer. [Figure 10] FIG. 10 is a schematic diagram showing the shape of a weld bead that forms the first bead layer when the lamination conditions are adjusted. [Figure 11] FIG. 11 is a schematic diagram showing the layer height of the first bead layer when the lamination conditions are adjusted. [Figure 12] FIG. 12 is a schematic diagram showing the layer height of each bead layer when the lamination conditions are adjusted. [Figure 13] FIG. 13 is a schematic diagram showing the layer height of each bead layer when the width of the weld bead is reduced by adjusting the layering conditions. [Figure 14] FIG. 14 is a schematic diagram showing how to slice the three-dimensional shape of a model. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The additive manufacturing system shown here uses a heat source device to melt a filler material (welding wire) held by a manipulator to form a weld bead, and then repeatedly stacks the formed weld beads into a desired shape to form a molded object made of stacked weld beads. The control information modification device modifies control information for controlling the additive manufacturing device that manufactures such a molded object.

[0012] <Additive manufacturing system configuration> An example of the configuration of an additive manufacturing system that is operated by the control information generated by the control information modifying device described above will be described. FIG. 1 is a schematic diagram showing the overall configuration of an additive manufacturing system. The additive manufacturing system 100 includes a manufacturing control device 15, a manipulator 17, a filler material supply device 19, a manipulator control device 21, and a heat source control device 23.

[0013] The manipulator control device 21 controls the manipulator 17 and the heat source control device 23. A controller (not shown) is connected to the manipulator control device 21, and an operator can instruct any operation of the manipulator control device 21 via the controller.

[0014] The manipulator 17 is, for example, an articulated robot, and a torch 11 attached to the tip shaft supports the filler material M so that it can be continuously supplied. The torch 11 holds the filler material M protruding from the tip. The position and posture of the torch 11 can be set arbitrarily in three dimensions within the range of the degrees of freedom of the robot arm constituting the manipulator 17. The manipulator 17 preferably has six or more degrees of freedom, and is preferably one that can arbitrarily change the axial direction of the heat source at the tip. The manipulator 17 may be in various forms, such as a four- or more-axis articulated robot as shown in FIG. 1, or a robot equipped with angle adjustment mechanisms on two or more orthogonal axes.

[0015] The torch 11 has a shield nozzle (not shown), through which shielding gas is supplied. The shielding gas blocks the atmosphere and prevents oxidation and nitridation of the molten metal during welding, thereby suppressing welding defects. The arc welding method used in this configuration may be either a consumable electrode type such as shielded metal arc welding or carbon dioxide gas arc welding, or a non-consumable electrode type such as TIG (Tungsten Inert Gas) welding or plasma arc welding, and is selected appropriately depending on the object to be formed. Here, gas metal arc welding will be used as an example. In the case of a consumable electrode type, a contact tip is disposed inside the shield nozzle, and a filler material M to which current is supplied is held by the contact tip. The torch 11 holds the filler material M and generates an arc from the tip of the filler material M in a shielding gas atmosphere.

[0016] The filler material supply device 19 supplies the filler material M toward the torch 11. The filler material supply device 19 includes a reel 19a around which the filler material M is wound, and a feeding mechanism 19b that feeds the filler material M from the reel 19a. The filler material M is fed to the torch 11 by the feeding mechanism 19b while being sent in the forward or reverse direction as needed. The feeding mechanism 19b is not limited to a push type that is arranged on the filler material supply device 19 side and pushes out the filler material M, but may also be a pull type or a push-pull type that is arranged on a robot arm or the like.

[0017] The heat source control device 23 is a welding power source that supplies the power required for welding by the manipulator 17. The heat source control device 23 adjusts the welding current and welding voltage supplied when forming a bead by melting and solidifying the filler material M. In addition, the filler material supply speed of the filler material supply device 19 is adjusted in conjunction with the welding conditions such as the welding current and welding voltage set by the heat source control device 23.

[0018] The heat source for melting the filler material M is not limited to the arc described above. Other heat sources may be used, such as a heating method that combines an arc and a laser, a heating method that uses plasma, or a heating method that uses an electron beam or a laser. Heating with an electron beam or a laser allows for more precise control of the amount of heat, which can maintain the state of the formed bead more appropriately and contribute to further improving the quality of the laminated structure. The material of the filler material M is also not particularly limited. The type of filler material M used may vary depending on the characteristics of the object W, such as mild steel, high-tensile steel, aluminum, aluminum alloy, nickel, or nickel-based alloy.

[0019] The molding control device 15 controls the above-mentioned parts in an integrated manner.

[0020] The additive manufacturing system 100 configured as described above operates in accordance with a manufacturing program created based on a manufacturing plan for the object W. The manufacturing program is composed of a large number of command codes and is created based on an appropriate algorithm depending on various conditions, such as the shape, material, and heat input of the object. According to this manufacturing program, the torch 11 is moved while the supplied filler material M is melted and solidified, and a linear weld bead B, which is a molten solid of the filler material M, is formed on the base 13. That is, the manipulator control device 21 drives the manipulator 17 and the heat source control device 23 based on a predetermined program provided from the manufacturing control device 15. In response to a command from the manipulator control device 21, the manipulator 17 moves the torch 11 while melting the filler material M with an arc to form the weld bead B. By sequentially forming and stacking the weld beads B in this manner, a desired object W is obtained.

[0021] 2 is a functional block diagram of the molding control device 15. The molding control device 15 includes a molding information acquisition unit 31, a predicted shape calculation unit 33, a change necessity determination unit 35, and a lamination condition adjustment unit 37, and functions as a control information correction device. Details of each unit will be described later, but the general functions are as follows.

[0022] The forming information acquisition unit 31 acquires forming information relating to the forming path of the weld bead B, the layering direction, and the layering conditions of the weld bead B.

[0023] Predicted shape calculation unit 33 calculates a predicted shape of a bead layer to be formed by laminating weld bead B based on the forming path of weld bead B and the lamination conditions of weld bead B acquired by forming information acquisition unit 31.

[0024] The change necessity determination unit 35 calculates the layer height (layer spacing) BLh of the bead layer BL consisting of the weld bead B based on the predicted shape calculated by the predicted shape calculation unit 33, and determines whether or not the layering conditions of the weld bead B need to be changed based on the distribution of this layer height BLh.

[0025] When change necessity determination unit 35 determines that the lamination conditions of weld bead B need to be changed, lamination condition adjustment unit 37 adjusts the lamination conditions of weld bead B for each location.

[0026] The above-mentioned molding control device 15 is configured by hardware using an information processing device such as a PC (Personal Computer). Each function of the molding control device 15 is realized by a control unit (not shown) reading and executing a program having a specific function stored in a storage device (not shown). Examples of the storage device include a memory such as a random access memory (RAM) which is a volatile storage area, a read only memory (ROM) which is a non-volatile storage area, and storage such as a hard disk drive (HDD) or a solid state drive (SSD). Examples of the control unit include a processor such as a central processing unit (CPU) or a microprocessor unit (MPU), or a dedicated circuit. In addition to the above-mentioned configurations, the molding control device 15 may be another computer remotely connected to the additive manufacturing system 100 via a network or the like.

[0027] <Control information generation procedure> FIG. 3 is a flowchart showing a procedure for modifying control information by the control information modifying device.

[0028] The manufacturing information acquisition unit 31 acquires, as manufacturing information, information on the manufacturing path, lamination direction, bead shape, and lamination conditions of the weld bead B (step S1).

[0029] The building path and layering direction in the building information of this weld bead B can be calculated by known means. For example, they can be generated by applying various trajectory patterns to shape data obtained by slicing a built object into multiple layers in CAD data or the like. Also, trajectory information generated and stored in advance may be loaded. Note that the trajectory information to be loaded may include, for example, coordinate information (X, Y, Z) of points included in the path of weld bead B, the pitch between the paths of adjacent weld beads B, the spacing between each bead layer, and the layering order of the paths of each weld bead B.

[0030] On the other hand, as for the information on the bead shape of weld bead B, information such as the shape model, bead height, and bead width of weld bead B is acquired.

[0031] As a shape model, it is desirable to use one that reproduces the phenomenon that occurs when weld beads B are actually stacked, such as a model that takes into account the overlap between adjacent weld beads B, or a model that reproduces the drooping shape toward the lower layer.

[0032] FIG. 4 shows an example of a model that takes into account the overlap between adjacent weld beads B. In each model, the cross-sectional shape of model BM1 of reference path P1 is a trapezoid, model BM2 of path PS2 is located adjacent to model BM1, and model BM3 of path PS3 is located adjacent to model BM2. Models BM2 and BM3 partially overlap the model located on the left side of FIG. 4. As a result, the shape of model BM2 is a polygonal shape (pentagon) that is close to one of the hypotenuses of model BM1, and the shape of model BM3 is a polygonal shape (pentagon) that is close to one of the hypotenuses of model BM2. In this way, each of BM1, BM2, and BM3 has a shape that approximates the cross-sectional shape of an actual weld bead.

[0033] FIG. 5 shows an example of a model that reproduces the shape of molten metal dripping downward. Among model BM1, which has a trapezoidal cross-sectional shape and is stacked on base 13, and models BM2, BM3, . . . , BMn (n is an integer) above model BM1, the trapezoidal bead models BM2, BM3, . . . , BMn above model BM1 have downwardly extending sagging portions 47A, 47B added to both ends of base 41. By setting models BM2, BM3, . . . , BMn with sagging portions 47A, 47B as bead models for stacking planning, the bead height of weld bead B is less affected by the sagging of molten metal that occurs at weld bead B. This makes it easier to match the predicted shape of the outline with the actual shape, even under conditions where molten metal from weld bead B is likely to drip, such as overhanging portions.

[0034] The bead width and bead height of the weld bead B may be related to welding conditions such as the welding speed and feed rate.

[0035] For example, the bead height H may be calculated from equation (1), and the bead width LW may be calculated from equation (2). H = C1 + C2 W f +C3T s +C4W f 2 +C5T s 2 +C6W f T s ...Equation (1) LW=D1+D2W f +D3T s +D4W f 2 +D5T s 2 +D6W f T s ...Equation (2) Ts: Torch movement speed Wf: Filler metal feeding speed C1~C6: Coefficients D1 to D6: Coefficients

[0036] The predicted shape calculation unit 33 calculates a predicted shape of the bead layer BL based on the shaping information acquired by the shaping information acquisition unit 31 (step S2). That is, the shape of the bead layer BL made of the weld bead B is predicted by providing information on the shaping path and layering direction of the weld bead B with layering conditions such as the welding current, welding voltage, feed rate, and welding speed. The shape of this bead layer BL may be predicted using the model shapes shown in Figures 4 and 5. When calculating the predicted shape of this bead layer BL, it is preferable to fix the conditions within the same pass in order to understand the relationship between the predicted shape and the layering conditions.

[0037] Here, Figures 6 and 7 show an example of the predicted shape of a cylindrical object W having a conical shape that is eccentric from the bottom to the top, and the predicted shape calculation unit 33 slices the shape of the object W and designs multiple bead layers BLi (i = 1 to N) consisting of weld beads Bi (i = 1 to N).

[0038] Thereafter, for each bead layer BLi (i = 1 to N) of weld bead B, starting from the bottom, change necessity determination unit 35 determines whether the lamination conditions need to be changed (steps S3, S4), and lamination condition adjustment unit 37 adjusts the lamination conditions (step S5).

[0039] In the determination of whether or not the change is necessary, first, the change necessity determining unit 35 calculates the distribution of the layer heights BLhi (i=1 to N) of the bead layers BLi (i=1 to N) based on the predicted shape (step S3).

[0040] Furthermore, the change necessity determination unit 35 determines for each bead layer BLi (i = 1 to N) whether or not the bead layer BLi (i = 1 to N) has an inclination angle θ that requires a change in the lamination conditions, based on the distribution of the layer heights BLhi (i = 1 to N) of each bead layer BLi (i = 1 to N) calculated based on the predicted shape (step S4).

[0041] If change necessity determination unit 35 determines that the lamination conditions of weld bead Bi (i = 1 to N) need to be changed (step S4: Yes), that is, if a certain deviation is found between the normal vector of bead layer BLi (i = 1 to N) and lamination direction Z, lamination condition adjustment unit 37 adjusts the lamination conditions of weld bead Bi (i = 1 to N) that forms that bead layer BLi (i = 1 to N) for each location (step S5).

[0042] 6 and 7, in the case of a manufacturing example in which a cylindrical object W having an eccentric conical shape from bottom to top is manufactured, the bead layers BLi (i = 1 to N) have, in the circumferential direction, stacked portions that are stacked approximately vertically along the stacking direction Z and stacked portions that are stacked obliquely at an inclination angle θ with respect to the stacking direction Z. Therefore, in this manufacturing example, as shown in FIG. 8, a difference occurs in the layer height BLhi (i = 1 to N) of the bead layers BLi (i = 1 to N) depending on the inclination angle θ between the stacking direction Z and the side surface of the layered shape. As shown in FIG. 9, for example, in a stacked portion (the right side in FIG. 9) that is stacked vertically (θ = 0°) without inclination along the stacking direction Z, the bead height of the weld bead Bi is approximately the same as the layer height BLhi of the bead layer BLi. On the other hand, at a layering location (left side in FIG. 9) that is inclined at an inclination angle θ (θ≠0°) with respect to the layering direction Z, the maximum bead height of the weld bead Bi does not become the layer height BLhi of the bead layer BLi. Therefore, when the predicted shape of the weld bead Bi is taken into consideration, the bead layer BLi in the molded object W will no longer have the layer boundary shown in FIG. 7. Then, as deviations in the layer heights BLhi (i = 1 to N) accumulate, the layer boundary surfaces of the bead layers BLi (i = 1 to N) will gradually become inclined, as shown in FIG. 8.

[0043] In a modeling example for forming such a model W, first, the change necessity determination unit 35 extracts the maximum value BLh1max and minimum value BLh1min of the layer height BLh1 for the first bead layer BL1, and determines whether the difference between the maximum value BLh1max and minimum value BLh1min of the layer height BLh1 falls within a threshold value ε (step S4).

[0044] Next, layering condition adjustment unit 37 adjusts the layering conditions so that the layer height BLh1 of the first bead layer BL1 is uniform (step S5). Specifically, based on the inclination angle θ at each location of bead layer BL1, the layering conditions, such as the welding current, welding voltage, feed rate, and welding speed, are adjusted. As a result, the deposition amount of weld bead B1 is adjusted for each location Pa, Pb, Pc, etc., as shown in FIGS. 10 and 11. As a result, the deposition amount of weld bead B1 is increased or decreased for each location, changing from before the deposition amount adjustment (dashed line in FIG. 11) to after the deposition amount adjustment (solid line in FIG. 11). For example, the deposition amount of weld bead B1 is reduced in a lamination area (right side in FIG. 11) where the lamination is vertical (θ=0°) without inclination relative to lamination direction Z, and the deposition amount of weld bead B1 is increased in a lamination area (left side in FIG. 11) where the lamination is inclined at an inclination angle θ (θ≠0°) relative to lamination direction Z. This results in a uniform layer height BLh1 of bead layer BL1 formed from weld bead B1 (see FIG. 11). The deposition amount of weld bead B is preferably adjusted so that the layer height BLh1 of bead layer BL1 becomes a preset reference layer height BLhs. Note that if change necessity determination unit 35 determines that the lamination conditions of weld bead B1 do not need to be changed (step S4: No), lamination condition adjustment unit 37 maintains the lamination conditions of weld bead B1 that form bead layer BL1 as they are.

[0045] Thereafter, the change necessity determination process (steps S3, S4) and the lamination condition change process (step S5) are repeated (step S6). As a result, if it is determined that the lamination conditions of weld beads Bi (i = 2 to N) for the second or subsequent bead layers BLi (i = 2 to N) need to be changed (step S4: No), the lamination conditions of weld beads Bi (i = 2 to N) that form the bead layer BLi (i = 2 to N) are adjusted (step S5), and the layer height BLhi (i = 2 to N) is adjusted.

[0046] As a result, the layer heights BLhi (i = 1 to N) of the bead layers BLi (i = 1 to N) formed by the weld beads Bi (i = 1 to N) are uniform, as shown in Fig. 12. Therefore, even if an overhang portion is included in part of the object W, local deviations in the layer heights BLhi (i = 1 to N) can be suppressed, and a high-quality object W can be smoothly manufactured.

[0047] The determination of whether or not a change is necessary by the change necessity determination unit 35 (step S4) may be performed by extracting the layer heights BLhi1 and BLhi2 at two specific locations for each bead layer BLi (i = 1 to N) and determining whether or not the difference between these BLhi1 and BLhi2 is within a threshold value (tolerance value) ε.

[0048] Furthermore, adjusting the deposition conditions for weld bead B to adjust the deposition rate may result in excess metal in areas where the deposition rate has increased. For this reason, the bead width of weld bead B may also be adjusted in conjunction with the deposition rate adjustment. For example, the bead width of weld bead B may be limited by adjusting the weaving, the tilt angle of torch 11, or the heat input, thereby adjusting the bead height while suppressing an increase in bead width. As a result, as shown in FIG. 13, the layer heights BLhi (i = 1 to N) of bead layers BLi (i = 1 to N) can be made uniform while suppressing the occurrence of excess metal due to an increase in the deposition rate.

[0049] As described above, according to this configuration example, the layering conditions of the weld bead B are adjusted for each location to reduce variations in the layer height BLh of the bead layer BL, so that it is possible to suppress local deviations in the layer height BLh even if an overhanging portion is included in part of the object W. This reduces interference between the torch 11 and the object W being formed and errors in the arc start that may occur due to local deviations in the layer height BLh, and enables the smooth formation of a high-quality object W.

[0050] Note that if the adjustment amount of the lamination conditions for weld bead B within the same pass is significantly large, there is a risk of destabilizing the lamination process for weld bead B. In such cases, it is preferable to set a tolerance in advance, and if the adjustment amount of the lamination conditions exceeds the tolerance, to repeatedly correct at least one of the number of divisions of the target shape of the shaped object W and the lamination direction Z of weld bead B until the adjustment amount becomes equal to or less than the tolerance.

[0051] For example, as shown in Figure 14, the three-dimensional shape of the created object W is sliced and divided into multiple bead layers BL (see left side of Figure 14), and then shape data with a larger number of divisions (see upper right of Figure 14) is repeatedly created until the adjustment amount falls within the allowable value. Alternatively, shape data with a layering direction Za tilted toward the side where the adjustment amount of the layer height BLh increases (see lower right of Figure 14) is repeatedly created until the adjustment amount falls within the allowable value. This reduces the amount of adjustment to the layering conditions for weld bead B within the same pass, and stabilizes the layering process for weld bead B.

[0052] As such, the present invention is not limited to the above-described embodiments, and the present invention also contemplates the mutual combination of the various components of the embodiments, as well as modifications and applications by those skilled in the art based on the description in the specification and well-known techniques, and these modifications and applications are included in the scope of protection sought.

[0053] As described above, the present specification discloses the following: (1) A control information correction method for correcting control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers are stacked, the bead layers being obtained by dividing a target shape into multiple layers, the method comprising: a forming information acquisition process for acquiring forming information regarding a forming path, a layering direction, and layering conditions of the weld bead that forms the bead layer; a predicted shape calculation step of calculating a predicted shape of the bead layer based on the shaping information; a change necessity determination step of determining whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjusting step of adjusting the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer when it is determined that the lamination conditions need to be changed; A control information modification method, comprising: According to this control information correction method, the weld bead layering conditions are adjusted for each location to reduce variations in the bead layer height, making it possible to suppress local deviations in layer height even if the object includes an overhanging portion. This reduces interference between the torch and the object being built and arc start errors that may occur due to local deviations in layer height, enabling the smooth production of high-quality objects.

[0054] (2) A control information correction method according to (1), wherein in the change necessity determination step, a distribution of layer heights based on the predicted shape of the bead layer is calculated, and if the difference in layer heights between the bead layers is greater than a preset threshold, it is determined that the lamination conditions need to be changed. According to the control information correction method configured as above, it is possible to appropriately determine whether or not the lamination conditions need to be changed depending on whether or not there is an overhang portion or a curved surface.

[0055] (3) The control information correction method according to (2), wherein the layer height distribution is calculated based on an inclination angle of a surface of the object with respect to the stacking direction. According to the control information correction method configured as above, by taking into consideration the inclination angle of the surface of the object, it is possible to obtain an accurate layer height distribution for each location.

[0056] (4) A control information correction method according to any one of (1) to (3), further comprising a step of repeatedly correcting, when an adjustment amount of the adjusted stacking conditions becomes larger than a preset tolerance, at least one of the number of divisions of the target shape of the object and the stacking direction of the weld bead until the adjustment amount becomes equal to or smaller than the tolerance. According to the control information correction method configured as described above, the adjustment amount due to the change in the lamination conditions for each bead layer can be prevented from becoming excessively large, and the lamination process can be stabilized.

[0057] (5) A control information correction device that corrects control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers obtained by dividing a target shape into multiple layers are stacked, the control information correction device comprising: a forming information acquisition unit that acquires forming information regarding a forming path, a layering direction, and layering conditions of the weld bead that forms the bead layer; a predicted shape calculation unit that calculates a predicted shape of the bead layer based on the shaping information; a change necessity determination unit that determines whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjusting unit that adjusts the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer when it is determined that the lamination conditions need to be changed; A control information modifying device comprising: This control information correction device adjusts the weld bead layering conditions for each location to reduce variations in the bead layer height, thereby suppressing local deviations in layer height even if the object includes an overhanging portion. This reduces interference between the torch and the object being built and arc start errors that may occur due to local deviations in layer height, enabling the smooth production of high-quality objects.

[0058] (6) A program for correcting control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers are stacked, the bead layers being obtained by dividing a target shape into multiple layers, the program comprising: On the computer, a forming information acquisition function for acquiring forming information regarding a forming path, a lamination direction, and lamination conditions of the weld bead that forms the bead layer; a predicted shape calculation function for calculating a predicted shape of the bead layer based on the shaping information; a change necessity determination function that determines whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjustment function that, when it is determined that the lamination conditions need to be changed, adjusts the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer; A program to make this happen. This program adjusts the welding bead layering conditions for each location to reduce variations in bead layer height, thereby suppressing local deviations in layer height even if the object includes an overhanging portion. This reduces interference between the torch and the object being built and arc start errors that can occur due to local deviations in layer height, enabling the smooth production of high-quality objects. [Explanation of symbols]

[0059] 11 Torch 15. Forming control device (control information correction device) 31 Modeling information acquisition section 33 Predicted shape calculation unit 35 Change necessity determination section 37 Lamination Condition Adjustment Section 100 Additive Manufacturing System (Additive Manufacturing Device) B Weld bead W sculpture θ Tilt angle

Claims

1. 1. A control information correction method for correcting control information for controlling an additive manufacturing apparatus that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers are stacked, the bead layers being obtained by dividing a target shape into a plurality of layers, the method comprising: a forming information acquisition process for acquiring forming information regarding a forming path, a layering direction, and layering conditions of the weld bead that forms the bead layer; a predicted shape calculation step of calculating a predicted shape of the bead layer based on the shaping information; a change necessity determination step of determining whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjusting step of adjusting the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer when it is determined that the lamination conditions need to be changed; Including, In the change necessity determining step, a distribution of layer heights is calculated based on the predicted shape of the bead layer, and when a difference in layer heights between the bead layers is greater than a preset threshold value, it is determined that the lamination conditions need to be changed. Control information modification method.

2. the layer height distribution is calculated based on an inclination angle of a surface of the object with respect to the stacking direction; The control information modifying method according to claim 1 .

3. and when an adjustment amount of the adjusted lamination conditions becomes larger than a preset tolerance, repeatedly correcting at least one of the number of divisions of the target shape of the shaped object and the lamination direction of the weld beads until the adjustment amount becomes equal to or smaller than the tolerance.

3. The control information modifying method according to claim 1 or 2.

4. A control information correction device that corrects control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers that are obtained by dividing a target shape into a plurality of layers are stacked, a forming information acquisition unit that acquires forming information regarding a forming path, a layering direction, and layering conditions of the weld bead that forms the bead layer; a predicted shape calculation unit that calculates a predicted shape of the bead layer based on the shaping information; a change necessity determination unit that determines whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjusting unit that adjusts the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer when it is determined that the lamination conditions need to be changed; Including, the change necessity determination unit calculates a distribution of layer heights based on the predicted shape of the bead layer, and determines that the lamination conditions need to be changed when a difference in layer heights between the bead layers is greater than a preset threshold value; Control information modification device.

5. A program for correcting control information for controlling an additive manufacturing device that melts a welding material while moving a torch along a manufacturing path to form a weld bead on a target surface, and manufactures a three-dimensional object in which bead layers obtained by dividing a target shape into a plurality of layers are stacked, the program comprising: On the computer, a forming information acquisition function for acquiring forming information regarding a forming path, a lamination direction, and lamination conditions of the weld bead that forms the bead layer; a predicted shape calculation function for calculating a predicted shape of the bead layer based on the shaping information; a change necessity determination function that determines whether or not the lamination conditions need to be changed based on the predicted shape; a lamination condition adjustment function that, when it is determined that the lamination conditions need to be changed, adjusts the lamination conditions of the weld bead for each location to reduce variations in layer height of the bead layer; Including, the change necessity determination function calculates a distribution of layer heights based on the predicted shape of the bead layer, and determines that the lamination conditions need to be changed when a difference in layer heights between the bead layers is greater than a preset threshold value; In order to realize this, program.

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