Methods for manufacturing layered shapes

Abstract

In the molding process, the following processes are performed: substrate measurement processing, which uses a shape sensor to measure the height of the substrate at the predetermined position where the welding torch moves during the stacking of weld beads, and obtains the measured height; welding condition setting processing, which calculates the planned height of the substrate at the predetermined position where the welding torch moves according to the stacking plan, compares the measured height obtained through substrate measurement processing with the planned height to obtain the difference height, and sets the welding conditions in the feedback correction to reduce the difference height; and correction ratio update processing, which selects from a number of preset correction ratios and updates the correction ratio in the welding conditions based on the selected correction ratio.

Description

Technical Field

[0001] This invention relates to a method for manufacturing layered structures. Background Technology

[0002] In recent years, the demand for 3D printers as a means of production has increased, especially regarding their application to metal materials. Research and development are underway in industries such as aircraft for practical application. 3D printers using metal materials use heat sources such as lasers and electric arcs to melt metal powder or filaments and layer the molten metal to create shapes.

[0003] As a technique for shaping objects using welding, Patent Document 1 discloses the following technology: measuring the height of the formed object using a measuring unit, and controlling the processing conditions when a new layer is stacked at the measuring position based on the measurement results.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 6576593 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, in feedback control when shaping an object by stacking weld beads, if the height deviation of the base portion is locally larger than expected, sometimes the correction of processing conditions through conventional feedback control is ineffective, making it difficult to stably stack weld beads. For example, at the beginning and end of a weld bead, there is a tendency for the height deviation of the lower weld bead to increase, which is difficult to handle with conventional feedback control.

[0009] Therefore, the object of the present invention is to provide a method for manufacturing a stacked molded object that can stably form weld beads and achieve a good shape by means of appropriate feedback control.

[0010] Solution for solving the problem

[0011] The present invention is composed of the following structure.

[0012] A method for manufacturing a layered shape involves shaping the object by simultaneously moving a welding torch and layering weld beads formed by melting and solidifying filler material using the torch.

[0013] The method for manufacturing the stacked structure includes the following shaping process: based on a stacking plan determined according to the shape of the weld bead obtained from the target shape of the structure and the track of the welding torch used to form the weld bead, the welding torch is moved to stack the weld bead.

[0014] In the molding process, the following treatment is performed:

[0015] The substrate measurement process uses a shape sensor to measure the height of the substrate at a predetermined position where the welding torch moves when the weld beads are stacked, thereby obtaining the measured height.

[0016] The welding condition setting process involves determining the planned height of the substrate at the predetermined position of the welding torch movement based on the stacking plan, comparing the measured height obtained through substrate measurement processing with the planned height to calculate the difference height, and setting welding conditions in feedback correction to reduce the difference height; and

[0017] The correction ratio update process selects from a plurality of preset correction ratios and updates the correction ratio in the welding conditions based on the selected correction ratio.

[0018] Invention Effects

[0019] This invention achieves a stable and well-shaped object by implementing appropriate feedback control. Attached Figure Description

[0020] Figure 1 This is a schematic outline diagram of a manufacturing system for manufacturing stacked objects using the manufacturing method according to an embodiment of the present invention.

[0021] Figure 2 This is a diagram showing the wall portion formed by stacking layers of weld beads. Figure 2 (A) and (B) are outline side views, respectively.

[0022] Figure 3 This diagram illustrates the process of creating a wall shape by layering weld beads. Figure 3 (A) to (E) are outline side views of the wall.

[0023] Figure 4 It is a chart showing the correction ratios in the welding conditions.

[0024] Figure 5 It is a diagram showing the shape of the weld bead. Figure 5 (A) is a top view of the weld bead with bends. Figure 5 (B) is a top view of the weld bead with intersections. Detailed Implementation

[0025] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0026] Figure 1This is a schematic outline structural diagram of a manufacturing system 100 for manufacturing stacked objects using the manufacturing method according to an embodiment of the present invention.

[0027] The manufacturing system 100 for the stacked model of this structure includes a welding robot 11, a robot controller 13, a filler material supply unit 15, a welding power source 19, and a control unit 21.

[0028] The welding robot 11 is a jointed robot, with a welding torch 23 supported on its front axis. The position and orientation of the welding torch 23 can be arbitrarily set in three dimensions within the range of the robot arm's degrees of freedom. The welding torch 23 holds the filler material (welding wire) M continuously supplied from the filler material supply unit 15 in a state where it protrudes from the front end of the torch. A shape sensor 25 is provided on the front axis of the welding robot 11 together with the welding torch 23.

[0029] The welding torch 23 has a protective nozzle (not shown) and supplies shielding gas to the welding area from the protective nozzle. As an arc welding method, it can be any of the consumable electrode types such as covered arc welding or gas carbonate arc welding, or the non-consumable electrode types such as TIG welding or plasma arc welding, and the appropriate type is selected according to the stacked shape being produced.

[0030] For example, in the case of a consumable electrode type, a conductive tip is disposed inside the protective nozzle, and the filler material M supplied with molten current is held in the conductive tip. While holding the filler material M, the welding torch 23 generates an arc from the tip of the filler material M under a protective gas atmosphere. The filler material M is fed to the welding torch 23 by a feed mechanism (not shown) mounted on a robotic arm or the like. Furthermore, as the continuously fed filler material M melts and solidifies while the welding torch 23 is moved, a weld bead 29, which is the molten solidified filler material M, is formed on the base plate 27.

[0031] The base plate 27 is made of metal plates such as steel plates, and is generally larger than the bottom surface (the lowest surface) of the stacked structure W. The base plate 27 is not limited to a plate shape, and can also be a base of other shapes such as a block or a rod.

[0032] The heat source for melting the filler material M is not limited to the electric arc described above. For example, other heat sources based on methods such as heating with both electric arc and laser, heating with plasma, or heating with electron beam or laser can also be used. When heating with electron beam or laser, the amount of heat can be controlled more precisely, the state of the weld bead can be maintained more appropriately, and this can help to further improve the quality of the laminated structure.

[0033] The filler material M can use all commercially available welding wires. For example, it can use solid welding wires for MAG welding and MIG welding of mild steel, high-tensile steel and low-temperature steel (JIS Z 3312), and flux-cored welding wires for arc welding of mild steel, high-tensile steel and low-temperature steel (JIS Z 3313).

[0034] As filler material M, active metals such as titanium can also be used. In this case, in order to avoid oxidation and nitriding caused by reaction with the atmosphere during welding, the weld area needs to be set to a protective gas atmosphere.

[0035] A shape sensor 25 is mounted on the welding torch 23 and moves with it. This shape sensor 25 measures the shape of the portion that forms the substrate when the weld bead B is deposited. For example, a laser sensor that uses the reflected light from an irradiated laser as height data can be used as the shape sensor 25. It should be noted that a three-dimensional shape measurement camera can also be used as the shape sensor 25.

[0036] The robot controller 13 receives instructions from the control unit 21, drives the various parts of the welding robot 11, and controls the output of the welding power supply 19 as needed.

[0037] The control unit 21 is a computer device equipped with a CPU, memory, storage device, etc., and executes pre-prepared driver programs or driver programs created under desired conditions to drive various parts of the welding robot 11, etc. Thus, according to the driver programs, the welding torch 23 is moved, and multiple layers of weld beads 29 are deposited on the base plate 27 based on the created layering plan, thereby forming a multi-layered stacked structure W. Furthermore, a database 17 is connected to the control unit 21. This database 17 stores data on multiple correction ratios in the welding conditions for feedback correction.

[0038] Next, the case of manufacturing a layered model W using the manufacturing system 100 will be explained.

[0039] Figure 2 This is a schematic side view of a layered structure that forms the wall portion Wo by stacking linear weld beads 29 on the base plate 27. Figure 3 This is a process diagram showing the molding process of the shaped wall portion Wo, which is formed by the layered weld beads 29.

[0040] like Figure 2 As shown in (A), in the case of shaping the wall portion Wo, one end ( Figure 2 The left end of (A) is designated as the starting end. From this starting end, the welding torch 23 is moved to begin forming the weld bead 29, and the welding torch 23 is moved to the other end. Figure 2The formation of the weld bead 29 ends at the right end of (A). This linear weld bead 29 is formed repeatedly to create a wall shape Wo by stacking multiple linear weld beads 29. At this time, the control unit 21 uses a shape sensor 25, which is also provided on the welding torch 23, to measure the shape of the substrate and performs feedback corrections to adjust the welding conditions based on the measurement results.

[0041] In addition, such as Figure 2 As shown in (B), when the welding torch 23 is moved from the beginning to the end to form the weld bead 29, the formation of the weld bead 29 by the welding torch 23 is stable in the middle portion between the beginning and end portions of the weld bead 29. Therefore, in the middle region Am, it is possible to shape it into a shape with fewer irregularities along the target shape based on the stacking plan. Thus, in the middle region Am, which can be formed to this stable thickness, it is possible to handle it through normal feedback correction.

[0042] In contrast, in both the initial region As and the final region Ae, the thickness of the formed weld bead 29 tends to become unstable. Specifically, in the initial region As, the weld bead 29 tends to thicken and expand, while in the final region Ae, the weld bead 29 tends to thin and sag. Therefore, in the initial region As and the final region Ae where the thickness becomes unstable, conventional feedback correction may be ineffective.

[0043] In this case, in order to deal with the starting region As and the ending region Ae, the correction ratio of the welding conditions in the feedback correction can be increased. However, in the intermediate region Am, where the weld bead 29 can be stably formed, the sharp correction will produce a large unevenness.

[0044] Therefore, in the manufacturing method of this embodiment, the following feedback correction is performed in the molding process of stacking 29 weld beads.

[0045] (Substrate measurement processing)

[0046] The height of the substrate at a predetermined position when the welding torch 23 moves to the desired location during the stacking of the weld beads 29 is measured using a shape sensor 25. Furthermore, the measured height Hr, which is the height of the substrate measured using the shape sensor 25, is obtained.

[0047] (Welding condition setting process)

[0048] The planned height Hp of the substrate at the predetermined position of the welding torch 23 is determined according to the stacking plan. The measured height Hr obtained by substrate measurement processing is compared with the planned height Hp to obtain the difference height ΔH (ΔH = Hr - Hp). The welding conditions are set by reducing the difference height ΔH.

[0049] (Adjusted ratio update processing)

[0050] Based on the shape characteristics of the predetermined position of the welding torch 23, a plurality of preset correction ratios are selected. These correction ratios are estimated in advance, for example through experiments, to stably form the weld bead 29 for various shape characteristics, and are stored in the database 17. Furthermore, based on the selected correction ratio, the correction ratio in the welding conditions (e.g., the ratio of increase or decrease in welding speed relative to the differential height ΔH) is updated. For example, in the case of unstable thickness regions such as the beginning region As and the end region Ae of the shaped wall portion Wo, correction ratios corresponding to the shape characteristics of these regions are selected and exported from the database 17, and the correction ratio of the welding conditions is updated to the selected correction ratio. It should be noted that in this correction ratio update process, if the predetermined position of the welding torch 23 has a shape characteristic that does not require updating the correction ratio of the welding conditions, no correction ratio is selected, and the correction ratio in the welding conditions set by the welding condition setting process is maintained. For example, in the case of stable thickness regions such as the middle region Am of the shaped wall portion Wo, the correction ratio in the welding conditions set by the welding condition setting process is maintained.

[0051] When updating the aforementioned correction ratio, a maintenance period (correction interval Δt) can also be set to maintain the changed correction ratio as is for a specified period. The correction interval Δt can be set by time or by the length along the track number. Alternatively, a fixed correction interval Δt can be set only for a specific correction ratio.

[0052] Without setting a correction interval Δt, correction control is performed for a short period of time in response to changes in the local height (substrate height) of the existing weld bead. Depending on the conditions, the correction control may sometimes become a transient response. In this case, the height of the newly formed weld bead may increase compared to the local unevenness of the substrate.

[0053] Therefore, by setting a correction interval Δt to suppress the sensitivity of the correction control, localized abrupt height changes are avoided, and the response is moderated in a way that results in a gently undulating substrate shape. This makes height correction of the subsequently formed layer (upper layer) easier.

[0054] Next, an example of feedback correction during the shaping process of the Wo part of the shaped wall will be explained.

[0055] Figure 4 It is a chart showing the correction ratios in the welding conditions. Figure 5 This is a top view showing the shape of the weld bead 29.

[0056] (Starting region As)

[0057] like Figure 3 As shown in (A), a shape sensor 25, which is also provided on the welding torch 23, is positioned at the beginning portion of the substrate U of the molded body WA, which has been formed by stacking weld beads 29. The shape sensor 25 and the welding torch 23 are moved along the molded body WA. Furthermore, the height of the beginning region As of the substrate U in the molded body WA is measured using the shape sensor 25, and the measured height Hr is obtained (substrate measurement processing).

[0058] The control unit 21 calculates the planned height Hp of the substrate U based on the stacking plan, and compares the measured height Hr obtained by the shape sensor 25 with the planned height Hp. Furthermore, it calculates the difference height ΔH between the measured height Hr and the planned height Hp (ΔH = Hr - Hp), and sets the welding conditions by reducing the difference height ΔH (welding condition setting process).

[0059] Here, Figure 4 The feedback correction shows the difference height ΔH and the correction ratio of welding speed. The control unit 21 is set, for example, to the correction ratio Fa (as in normal feedback correction). Figure 4 Welding conditions (solid lines in the diagram).

[0060] Next, the control unit 21 performs a correction ratio update process for the correction ratio in the updated welding conditions. Specifically, the starting region As is a region with a large variation in height, so the correction ratio Fb corresponding to the shape characteristics of the starting region As is selected from multiple correction ratios set according to shape characteristics stored in the database 17. Figure 4 (The dotted line in the diagram). Furthermore, the correction ratio Fa in the welding conditions is updated to the selected correction ratio Fb. This correction ratio Fb has a larger change in welding speed relative to the differential height ΔH compared to the correction ratio Fa. By updating to this correction ratio Fb, the welding speed can be rapidly changed relative to the differential height ΔH in the feedback correction.

[0061] like Figure 3 As shown in (B), the shape sensor 25 and the welding torch 23 are moved along the shape body WA towards the end side, and the welding torch 23 is used to deposit weld beads 29 into the starting region As in the substrate U. At this time, feedback correction is performed using a correction ratio Fb that can rapidly change the welding speed relative to the difference height ΔH. Therefore, for large shape changes in the difference height ΔH, the height of the weld beads 29 formed by the welding torch 23 can be rapidly corrected.

[0062] (Middle area Am)

[0063] During the formation of the weld bead 29 in the starting region As by the welding torch 23, the shape sensor 25, which is also installed on the welding torch 23, continues to measure the height of the middle region Am of the substrate U (substrate measurement processing). Furthermore, the measured height Hr is compared with the planned height Hp to calculate the difference height ΔH (ΔH = Hr - Hp), and the difference height ΔH is reduced, for example, by setting it to the correction ratio Fa used in normal feedback correction. Figure 4 The welding conditions (welding condition setting process) are shown in the solid line in the image.

[0064] Next, the control unit 21 performs a correction ratio update process for the correction ratio in the welding conditions. Here, the intermediate region Am is a region with relatively small changes in height and stable shape characteristics; therefore, in the correction ratio update process, the control unit 21 does not select a correction ratio from the database 17, but maintains the correction ratio Fa (set in the welding conditions through the welding condition setting process). Figure 4 (The solid line in the middle).

[0065] like Figure 3 As shown in (C), the shape sensor 25 and the welding torch 23 are moved along the shape body WA towards the end side, and the weld bead 29 is deposited in the middle region Am of the welding torch 23 in the substrate U. At this time, feedback correction is performed using a correction ratio Fa that makes the welding speed change smoothly with respect to the difference height ΔH. Therefore, for small shape changes in the difference height ΔH, the height of the weld bead 29 formed by the welding torch 23 can be smoothly corrected.

[0066] (Terminal Area Ae)

[0067] like Figure 3 As shown in (D), after the shape sensor 25 reaches the terminal region Ae in the base U of the model WA, the height of the terminal region Ae is measured using the shape sensor 25, and the measured height Hr is obtained (base measurement processing). Furthermore, the measured height Hr is compared with the planned height Hp of the base U based on the stacking plan, and the difference height ΔH (ΔH = Hr - Hp) is calculated. This difference height ΔH is then set as a correction ratio Fa to reduce the difference height Fa. Figure 4 The welding conditions (welding condition setting process) are shown in the solid line in the image.

[0068] Next, the control unit 21 performs a correction ratio update process for the correction ratio in the updated welding conditions. Specifically, the terminal region Ae is a region with a large variation in height, so the control unit 21 selects the correction ratio Fb corresponding to the shape characteristics of the terminal region Ae from multiple correction ratios set according to shape characteristics stored in the database 17. Figure 4(The dotted line in the diagram) and update the correction ratio Fa in the welding conditions to the selected correction ratio Fb. Here, the correction ratio corresponding to the shape characteristics of the terminal region Ae is set to the correction ratio Fb corresponding to the shape characteristics of the starting region As. It should be noted that the correction ratios corresponding to the shape characteristics of the starting region As and the terminal region Ae can also be different.

[0069] like Figure 3 As shown in (E), a weld bead 29 is deposited onto the terminal region Ae using a welding torch 23 that reaches the terminal region Ae. At this time, a feedback correction is performed using a correction ratio Fb that allows the welding speed to change rapidly relative to the difference height ΔH. Therefore, the height of the weld bead 29 formed by the welding torch 23 can be rapidly corrected for large shape changes in the difference height ΔH.

[0070] As explained above, in the method for manufacturing a stacked model according to this embodiment, the correction ratio of the welding conditions in the feedback correction that reduces the height difference ΔH between the planned height Hp based on the stacking plan and the actual measured height Hr is updated to a correction ratio selected from a plurality of pre-set correction ratios. Therefore, feedback correction can be performed with an appropriately selected correction ratio to stably form the weld bead 29 for various height deviations.

[0071] For example, a smaller correction ratio is set for positions with average and gentle height deviations, and a larger correction ratio is set for localized and larger height deviations, so that the weld bead 29 can be stably formed in an appropriate control mode according to the shape characteristics of the shaped part of the weld bead 29.

[0072] It should be noted that the correction ratio is not limited to the case where multiple ratios are preset according to shape characteristics. Multiple correction ratios can also be preset according to positions specified based on the stacking plan. Such specified positions include, for example, positions that are prone to local variation, such as the frame portion, the fill portion within the frame portion, the corner portion of the frame portion, and the overhang portion.

[0073] For example, such as Figure 5 As shown in (A), the bent portion 51 when the weld bead 29 is bent and stacked, and as shown in (A) Figure 5When the weld beads 29 are stacked in a cross shape as shown in (B), the intersections 53, etc., tend to have localized variations in the stacking height of the weld beads 29. Therefore, these bends 51, intersections 53, or both, are pre-defined as designated positions, and a correction ratio corresponding to each designated position is set. Furthermore, when forming the weld beads 29, at the designated positions such as bends 51 and intersections 53, a correction ratio corresponding to each designated position is selected, and the correction ratio in the feedback correction welding conditions is updated to the selected correction ratio. As a result, the weld beads 29 can be formed while simultaneously handling rapid height variations at the designated positions such as bends 51 and intersections 53.

[0074] Alternatively, the base profile can be determined based on the measurement results of the shape sensor 25 on the front side of the moving direction of the welding torch 23, and the shape characteristics of the predetermined moving position of the welding torch 23 can be determined in real time based on the base profile and the target profile determined based on the stacking plan. Furthermore, in the correction ratio update process, a correction ratio corresponding to the shape characteristics determined in the modeling can be selected from a plurality of preset correction ratios, and the correction ratio in the welding conditions can be updated based on the selected correction ratio.

[0075] In this way, when forming the weld bead 29, the shape of the substrate can be sensed in real time, and the weld bead 29 can be formed stably with appropriate control mode for unexpected large height deviations and local unevenness.

[0076] It should be noted that in the above embodiments, the correction ratio of welding speed relative to the differential height ΔH is set as a parameter in the feedback correction. However, the parameter as the correction ratio relative to the differential height ΔH is not limited to welding speed, but can also be the feed speed of filler material M or the amount of heat input used to generate an electric arc.

[0077] For example, when the feed rate of the filler material M is set as a parameter, the formation height of the weld bead 29 can be increased by increasing the feed rate, and the formation height of the weld bead 29 can be decreased by decreasing the feed rate. Furthermore, when the heat input amount is set as a parameter, the formation height of the weld bead 29 can be decreased by increasing the heat input amount, and the formation height of the weld bead 29 can be increased by decreasing the heat input amount.

[0078] Furthermore, in the above embodiments, the shape sensor 25 is illustrated as being provided together with the welding torch 23, but the shape sensor 25 may not necessarily be provided together with the welding torch 23. For example, a robot that moves the shape sensor 25 may be provided in addition to the welding robot 11, and the shape of the substrate on the front side of the moving direction of the welding torch 23 that forms the weld bead 29 may be measured using this robot.

[0079] Thus, the present invention is not limited to the above-described embodiments. Combining the various structures of the embodiments with each other, as well as making changes and applications based on the description and well-known technologies by those skilled in the art, are also part of the present invention and are included within the scope of the claimed protection.

[0080] As stated above, the following matters are disclosed in this specification.

[0081] (1) A method for manufacturing a layered shape, wherein a welding torch is moved while layering weld beads formed by melting and solidifying filler material using the welding torch to shape the object, wherein...

[0082] The method for manufacturing the stacked structure includes the following shaping process: based on a stacking plan determined according to the shape of the weld bead obtained from the target shape of the structure and the track of the welding torch used to form the weld bead, the welding torch is moved to stack the weld bead.

[0083] In the molding process, the following treatment is performed:

[0084] The substrate measurement process uses a shape sensor to measure the height of the substrate at a predetermined position where the welding torch moves when the weld beads are stacked, thereby obtaining the measured height.

[0085] The welding condition setting process involves determining the planned height of the substrate at the predetermined position of the welding torch movement based on the stacking plan, comparing the measured height obtained through substrate measurement processing with the planned height to calculate the difference height, and setting welding conditions in feedback correction to reduce the difference height; and

[0086] The correction ratio update process selects from a plurality of preset correction ratios and updates the correction ratio in the welding conditions based on the selected correction ratio.

[0087] According to the manufacturing method of this layered structure, the correction ratio of welding conditions in the feedback correction that reduces the difference between the planned height based on the layering plan and the actual measured height is updated to a correction ratio selected from a plurality of pre-set correction ratios. Thus, feedback correction can be performed with an appropriately selected correction ratio to stably form weld beads for various height deviations.

[0088] (2) The manufacturing method of the layered model described in (1), wherein,

[0089] The plurality of correction ratios are set in correspondence with the shape characteristics of the locations where the deposited weld beads are stacked.

[0090] According to the manufacturing method of this layered model, for example, the correction ratio is set to be small for positions with average and gentle height deviations, and the correction ratio is set to be large for local and large height deviations, so that the weld bead can be stably formed in an appropriate control mode according to the shape characteristics of the model part of the weld bead.

[0091] (3) The method for manufacturing layered structures according to (2), wherein,

[0092] The plurality of correction ratios are preset based on the shape characteristics of the positions specified in the stacking plan.

[0093] According to the manufacturing method of this laminated structure, weld beads can be stably formed in an appropriate control mode based on the positions that can be pre-determined based on the laminated plan.

[0094] (4) The manufacturing method of the layered structure described in (2), wherein,

[0095] In the correction ratio update process, the base profile is obtained based on the measurement results of the shape sensor, the shape characteristics of the predetermined position of the welding torch are obtained based on the base profile and the target profile obtained based on the stacking plan, the correction ratio in the welding conditions is updated based on the shape characteristics from a plurality of preset correction ratios, and the correction ratio in the welding conditions is updated based on the selected correction ratio.

[0096] According to the manufacturing method of this layered model, the shape characteristics of the welding torch's predetermined movement position are determined in real time based on the substrate contour and the target contour, and a correction ratio is selected based on these shape characteristics. That is, while sensing the shape of the substrate in real time, the weld bead can be stably formed with an appropriate control mode to accommodate unexpected large height deviations and local unevenness.

[0097] It should be noted that this application is based on Japanese patent application (Japanese Patent Application No. 2021-000993) filed on January 6, 2021, the contents of which are referenced in this application.

[0098] Explanation of reference numerals in the attached figures

[0099] 23 welding torches

[0100] 29 weld beads

[0101] 25 shape sensors

[0102] Fa, Fb correction ratio ΔH difference height M filling material U base W layered model.

Claims

1. A method for manufacturing a layered shape, wherein a welding torch is moved while layering weld beads formed by melting and solidifying filler material using the welding torch to shape the object, wherein... The method for manufacturing the stacked structure includes the following shaping process: based on a stacking plan determined according to the shape of the weld bead obtained from the target shape of the structure and the track of the welding torch used to form the weld bead, the welding torch is moved from the beginning to the end to stack the weld bead. In the molding process, the following treatment is performed: The substrate measurement process uses a shape sensor to measure the height of the substrate at a predetermined position where the welding torch moves when the weld beads are stacked, thereby obtaining the measured height. The welding condition setting process calculates the planned height of the substrate at the predetermined position of the welding torch movement based on the stacking plan, compares the measured height obtained through the substrate measurement process with the planned height to calculate the difference height, and sets the welding conditions in the feedback correction to reduce the difference height. as well as The correction ratio update process selects from a plurality of correction ratios pre-defined corresponding to the shape characteristics of the locations where the deposited weld beads are stacked, and updates the correction ratio in the welding conditions based on the selected correction ratio. and, When the predetermined position of the welding torch is the starting region where the weld bead layer is stacked, the welding conditions are updated by selecting a correction ratio corresponding to the shape characteristics of the starting region from a plurality of correction ratios set according to each shape characteristic for changing the welding speed. When the predetermined position of the welding torch is the terminal region where the weld bead layer is stacked, the welding conditions are updated by selecting a correction ratio from the plurality of correction ratios that corresponds to the shape characteristics of the terminal region. When the predetermined position of the welding torch is in the middle region between the starting region and the ending region, the set welding conditions are maintained without selecting the correction ratio.

2. The method for manufacturing a layered structure according to claim 1, wherein, At least one of the bending portion when the weld beads are bent and stacked, and the intersection portion when the weld beads are stacked in a cross shape, is set as a designated position as a predetermined position for the movement of the welding torch, and the correction ratio corresponding to the designated position is preset.

3. The method for manufacturing a layered structure according to claim 2, wherein, The plurality of correction ratios are preset based on the shape characteristics of the positions specified in the stacking plan.

4. The method for manufacturing a layered structure according to claim 2, wherein, In the correction ratio update process, the base profile is obtained based on the measurement results of the shape sensor, the shape characteristics of the predetermined position of the welding torch are obtained based on the base profile and the target profile obtained based on the stacking plan, the correction ratio in the welding conditions is updated based on the shape characteristics from a plurality of preset correction ratios, and the correction ratio in the welding conditions is updated based on the selected correction ratio.

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