Control information generation device, control information generation method, welding control device, and control information generation program

Abstract

To bring the shape of laminated weld beads close to a simulation shape based on a welding plan while considering the characteristics of the weld beads.SOLUTION: A control information generating device 33 for generating control information for controlling a lamination molding device for molding a layer shape using weld beads, and molding a three-dimensional structure in which the layer shape is laminated includes: a data acquisition part 331 for acquiring a characteristic profile of shape change of the weld beads 28 generated when a control condition is changed with respect to a simulation block body obtained by laminating a plurality of bead models simulating the shape of the weld beads 28; a measuring part 332 for measuring an actual shape including at least the height or the width of the molded three-dimensional structure; a calculation part 333 for comparing the simulation shape obtained by simulating the shape of the three-dimensional structure by lamination of the bead model, with the actual shape, and extracting a difference between both of the shapes; and a control information output part 334 for determining a correction value of the control condition eliminating the difference from the characteristic profile, and outputting the control information corrected according to the correction value.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] A technique for creating three-dimensional structures by layering weld beads formed by melting and solidifying filler material is known. Patent Document 1 discloses a system and method for providing positional feedback for additive manufacturing in such a technique. One or both of the output current, output voltage, output power, output circuit impedance, and wire feed rate are sampled during the additive manufacturing process when generating the current layer. Multiple instantaneous contact tip-to-work distance (CTWD) is determined based on at least one or both of the output current, output voltage, output power, output circuit impedance, and wire feed rate. The average CTWD is determined based on multiple instantaneous CTWDs. A correction factor used to compensate for any error in the height of the current layer is generated based on at least the average CTWD. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-107698 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, even if we can recognize the layer height error, selecting the appropriate conditions for correcting that error is difficult, considering factors such as the surrounding weld bead shape, location, and reference welding conditions. While it is conceivable to record the changes in weld bead height and width when the conditions are changed in each case, this is not practical due to the enormous number of experiments required.

[0005] Therefore, the present invention aims to provide a control information generation device, a control information generation method, a welding control device, and a control information generation program that can bring the shape of a stacked weld bead closer to a simulated shape based on a welding plan. [Means for solving the problem]

[0006] The present invention consists of the following configuration. (1) A control information generating device that generates control information for controlling an additive manufacturing device that creates a three-dimensional structure by stacking layers, which is formed by adding molten material to a workpiece surface to create a weld bead while moving the processing position along a predetermined path based on specified control conditions, and stacking the layered shapes, A data acquisition unit that acquires a characteristic profile of the shape change of the weld bead that occurs when the control conditions are changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead, A measuring unit that measures the actual shape of the fabricated three-dimensional structure, including at least the height or width of the structure, A calculation unit that compares the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracts the difference between the two shapes, A control information output unit that obtains a correction value for the control condition that eliminates the difference from the characteristic profile and outputs the corrected control information according to the correction value, A control information generation device equipped with the following features. (2) A method for generating control information for controlling an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, which is formed by adding molten material to a workpiece surface to create a weld bead while moving the processing position along a predetermined path based on specified control conditions, the apparatus being controlled by generating control information for control information, A data acquisition step to acquire a characteristic profile of the change in the shape of the weld bead that occurs when the control conditions are changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead. A measuring unit that measures the actual shape of the fabricated three-dimensional structure, including at least the height or width of the structure, A calculation step of comparing the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracting the difference between the two shapes, A control information output step includes obtaining a correction value for the control condition that eliminates the difference from the characteristic profile and outputting the corrected control information according to the correction value, A control information generation method comprising the following: (3) The control information generation device described in (1), A welding control device comprising a control unit that controls the additive manufacturing apparatus according to the results output by the control information generation device. (4) The welding control device described in (3), The aforementioned additive manufacturing apparatus, A welding apparatus equipped with the following features. (5) A control information generation program that generates control information for an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, by moving the processing position along a predetermined path based on specified control conditions, and applying molten processing material to the surface of the workpiece to form a weld bead, thereby creating a layered shape. A data acquisition step to acquire a characteristic profile of the change in the shape of the weld bead that occurs when the control conditions are changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead. A measurement step of measuring the actual shape of the fabricated three-dimensional structure, which includes at least the height or width of the structure, A calculation step of comparing the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracting the difference between the two shapes, A control information output step includes obtaining a correction value for the control condition that eliminates the difference from the characteristic profile and outputting the corrected control information according to the correction value, A control information generation program that causes a computer to execute commands. [Effects of the Invention]

[0007] According to the present invention, by comparing the simulated shape formed by laminating bead models along a welding plan with the actual shape formed by laminating welding beads, control information can be corrected according to the difference. Thereby, the control information generation device can bring the shape of the laminated welding beads closer to the simulated shape based on the welding plan while considering the characteristics of the welding beads.

Brief Description of the Drawings

[0008] [Figure 1] FIG. 1 is an overall configuration diagram of a welding apparatus according to an embodiment. [Figure 2] FIG. 2 is a block diagram of a control information generation device according to an embodiment. [Figure 3A] FIG. 3A is an explanatory diagram schematically showing the shape of a single welding bead formed by a laminated manufacturing apparatus. [Figure 3B] FIG. 3B is a graph schematically showing the relationship between the condition value of control conditions and the bead height H of the formed welding bead. [Figure 4] FIG. 4 is a prediction model for predicting the bead height, and is an explanatory diagram showing a pseudo-block body obtained by laminating a plurality of bead models. [Figure 5] FIG. 5 is a graph showing the characteristic profile of the shape change of the welding bead. [Figure 6] FIG. 6 is a prediction model for predicting the bead height, and is an explanatory diagram showing a pseudo-block body obtained by laminating a plurality of bead models. [Figure 7] FIG. 7 is a flowchart showing the steps of a method for manufacturing a three-dimensional structure implemented by a laminated manufacturing apparatus. [Figure 8] FIG. 8 is a graph explaining a method for eliminating the height difference according to an increase in the number of layers in which welding beads are laminated. [Figure 9] FIG. 9 is a graph explaining another method for eliminating the height difference according to an increase in the number of layers in which welding beads are laminated.

Embodiments for Carrying Out the Invention

[0009] Embodiments of the present invention will be described in detail below with reference to the drawings. This explanation uses the example of a case where a weld bead, formed by melting and solidifying filler material supplied from a welding head, is additively manufactured into a desired shape using an additive manufacturing device. However, the manufacturing method and the configuration of the additive manufacturing device are not limited to this. For example, a general welding device that performs fillet welding or butt welding may also be used.

[0010] (Welding equipment) Figure 1 is an overall configuration diagram of a welding apparatus for manufacturing molded objects. The welding apparatus 100 in this configuration comprises an additive manufacturing apparatus 11 and a welding control device 30 that controls the additive manufacturing apparatus 11. The additive manufacturing apparatus 11 comprises a welding robot 17 equipped with a welding head having a welding torch 15 on its tip axis, a robot controller 21 that drives the welding robot 17, a filler material supply unit 23 that supplies filler material (welding wire) M to the welding torch 15, and a welding power supply 25 that supplies welding current.

[0011] (Additive manufacturing equipment) The welding robot 17 is an articulated robot, and a welding torch 15 attached to the tip axis of the robot arm supports a continuously supplied filler material M at its tip. The position and orientation of the welding torch 15 can be arbitrarily set in three dimensions within the range of freedom of the robot arm by commands from the robot controller 21. A shape sensor 32 and a temperature sensor 26 are provided on the tip axis of the welding robot 17, which move together with the welding torch 15. The shape sensor 32 is a non-contact sensor that measures the shape of the weld bead 28 that is formed, and, if necessary, the shape around the bead formation position. Measurement by the shape sensor 32 may be performed simultaneously with the formation of the welding bead, or at different timings before or after bead formation. As the shape sensor 32, a laser sensor that detects the three-dimensional shape by the position of the reflected light of the irradiated laser beam, or by the time from the irradiation timing until the reflected light is detected, can be used. The shape sensor 32 is not limited to lasers; it may be a sensor with other detection methods.

[0012] The temperature sensor 26 is a contact-type sensor such as a radiation thermometer or thermograph, and detects the temperature (temperature distribution) at any position on the fabricated object. The welding torch 15 has a shield nozzle (not shown) and is a gas metal arc welding torch from which shielding gas is supplied. The arc welding method can be either a consumable electrode type such as shielded metal arc welding or carbon dioxide arc welding, or a non-consumable electrode type such as TIG welding or plasma arc welding, and is appropriately selected according to the additively fabricated object to be manufactured. For example, in the case of a consumable electrode type, a contact tip is placed inside the shield nozzle, and the filler material M to which the melting current is supplied is held by the contact tip. The welding torch 15 holds the filler material M and generates an arc from the tip of the filler material M in a shielding gas atmosphere.

[0013] The filler material supply unit 23 includes a reel 29 around which the filler material M is wound. The filler material M is sent from the filler material supply unit 23 to a feeding mechanism (not shown) attached to a robot arm or the like, and is fed to the welding torch 15 by the feeding mechanism, which feeds the material in forward and reverse directions as needed.

[0014] Any commercially available welding wire can be used as the filler material M. For example, welding wires specified in JIS Z 3312, MAG welding and MIG welding solid wires for mild steel, high-tensile steel, and low-temperature steel, and JIS Z 3313, etc., can be used. Furthermore, filler materials M such as aluminum, aluminum alloys, nickel, and nickel-based alloys can be used depending on the required properties. When the filler material M, which is continuously fed as described above, is melted and solidified by the arc, a weld bead 28, which is a molten and solidified body of the filler material M, is formed on the base plate 27. The base plate 27 is a metal plate such as a steel plate, but it is not limited to a plate shape; it may also be in other shapes such as a block, rod, or cylinder.

[0015] Specifically, the additive manufacturing apparatus 11 moves the processing position along a predetermined path based on specified control conditions, and uses the weld bead 28 formed by adding molten filler material M to the surface to be processed to create layer shapes as shown in Figure 1, thereby creating a three-dimensional structure by stacking these layer shapes.

[0016] (Welding control device and control information generation device) Next, the configuration of the welding control device 30 will be described. The welding control device 30 is a computer device similar to the robot controller 21, and is composed of hardware such as a processor that is in charge of the main control, a memory device, an input / output interface, an input unit, and an output unit. The welding control device 30 includes a control unit 31 and a control information generation device 33. The control unit 31 controls the additive manufacturing device 11 according to the results output by the control information generation device 33.

[0017] Next, the configuration of the control information generation device 33 will be described. As shown in Figure 2, the control information generation device 33 generates control information for controlling the additive manufacturing device 11. The control information generation device 33 comprises a data acquisition unit 331, a measurement unit 332, a calculation unit 333, and a control information output unit 334.

[0018] The data acquisition unit 331 acquires a characteristic profile of the shape change of the weld bead 28 that occurs when the control conditions are changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead 28.

[0019] The measurement unit 332 measures the actual shape, which includes at least the height or width of the fabricated three-dimensional structure.

[0020] The calculation unit 333 compares the simulated shape, which is a representation of the three-dimensional structure's shape obtained by stacking bead models, with the actual shape and extracts the difference between the two shapes.

[0021] The control information output unit 334 obtains a correction value for the control condition that eliminates the difference from the characteristic profile and outputs the corrected control information according to the correction value.

[0022] (Control by a control information generation device) Figure 3A is a schematic diagram illustrating the shape (cross-sectional shape) of a single weld bead 28 formed on the base plate 27 by the additive manufacturing apparatus 11. The bead height H, which is the height of the weld bead 28, is the distance from the bottom surface to the top surface of the weld bead 28. Generally, the shape of a single weld bead 28 varies depending on the welding conditions. Welding conditions include the welding current, welding voltage, the feed rate for the filler material (welding wire) M, and the welding speed.

[0023] Figure 3B is a schematic graph showing the relationship between the condition values ​​of the welding conditions (control conditions) and the bead height H of the weld bead 28 that is formed. As mentioned above, the condition values ​​include welding current, welding voltage, feed rate for the filler material M, and welding speed. When the condition value is welding speed, this graph shows that the bead height H decreases as the welding speed increases.

[0024] Conventional welding involves determining the required shape of the weld bead 28 and then formulating a welding plan based on empirically determined characteristics as shown in Figure 3B.

[0025] However, stacking multiple weld beads 28 can lead to shape changes that are difficult to predict based on the properties obtained so far. For example, the molten filler material M may flow downwards, resulting in a bead height H (the stacking height of the multiple weld beads 28) that is lower than the bead height H planned in the design.

[0026] Figure 4 is a conceptual diagram illustrating a predictive model for predicting bead height H in order to address the situation described above. In this prediction model, the computer first simulates the shape of the weld bead 28, particularly its cross-sectional shape, using a trapezoidal bead model, and obtains a pseudo-block body X by stacking multiple bead models B0, B1, B2...B1.

[0027] Such a pseudo-block X is the predicted shape of a laminate obtained by stacking weld beads 28 based on the welding plan. In acquiring the pseudo-block X, the computer also considers factors such as the overlap of the bead models and the amount of filler material M that melts and flows down, and can predict the pseudo-block X and its final bead height H, taking these factors into account.

[0028] However, even when using the prediction model described above, the bead height H of the multiple layers of weld beads 28 obtained in the actual fabrication (the height corresponding to the bead height H of the pseudo-block body X) may deviate from the predicted pseudo-block body X depending on the welding conditions, resulting in a discrepancy. Therefore, a more accurate prediction method is needed.

[0029] Therefore, in this embodiment, characteristic profiles of the shape changes of the weld bead 28 that occur under various welding conditions, i.e., control conditions, are acquired in advance. That is, the control information generation device 33 of this configuration acquires the characteristic profiles of the shape changes of the weld bead 28 that occur when the control conditions are changed for the pseudo-block body X described above, using the prediction model described above.

[0030] Furthermore, separate from the acquisition of characteristic profiles, the additive manufacturing apparatus 11 actually fabricates a three-dimensional structure corresponding to the pseudo-block body X described above under various control conditions, and the control information generation device 33 measures the actual shape, including its height (or width). The method for measuring the actual shape is not particularly limited, but examples include scanning the surface of the weld bead 28 using a measurement means such as a light sectioning method provided in the measurement unit 332, or a measurement means such as a laser sensor.

[0031] Furthermore, the control information generation device 33 compares the measured actual shape of the three-dimensional structure with a simulated shape obtained by stacking bead models (pseudo-blocks X) as shown in Figure 4. This allows the control information generation device 33 to extract the difference between the actual shape and the simulated shape.

[0032] Furthermore, when using actual shapes for comparison, considering that measurement errors may be included in the measurement results, the actual shape may be generated using the average height of the measurement results over a certain welding section. In addition, the simulated shape may be the shape obtained by adding excess material to the pseudo-block body X in Figure 4.

[0033] Finally, the control information generation device 33 obtains a correction value for the control condition that resolves this difference from the characteristic profile described above, and outputs corrected control information according to the correction value.

[0034] Figure 5 is a graph showing the characteristic profile of the shape change of the weld bead 28 when the control condition is welding speed. The horizontal axis is the welding speed (cpm), and the vertical axis is the difference in height (mm) that occurs when the welding speed is changed from the planned welding speed. For example, if the welding speed is set to 25 cpm, the build height can be increased by 0.3 mm compared to welding at the planned welding speed. In other words, Figure 5 is a graph that shows how the welding speed should be changed in response to the deviation of the actual height of the 3D build from the plan (height of the pseudo-block body X).

[0035] Let's consider a case where the difference extracted by the control information generation device 33 is -0.3 mm. In other words, this is a case where the height of the actually fabricated three-dimensional structure is 0.3 mm smaller than the planned height (height of the simulated block body X). It is preferable to make the difference between the actual shape and the simulated shape as close to zero as possible. According to the characteristic profile in Figure 5, in order to weld 0.3 mm higher than the planned welding conditions, the welding speed should be set to 25 cpm. In other words, by setting the additive manufacturing device 11 to a welding speed of 25 cpm, the difference can be made zero or approached zero.

[0036] Through this control, the control information generation device 33 can approximate the shape of the stacked weld beads 28, that is, the shape of the three-dimensional structure, to a simulated shape (planned shape) based on the welding plan, while taking into account the characteristics of the weld beads 28.

[0037] Note that in Figure 5, data with differences greater than 0.6 mm and data with differences less than -0.4 mm are not available. In such cases, the differences can be accumulated and calculated by combining multiple layers.

[0038] The characteristic profile in Figure 5 represents the characteristics of the shape change in the layer height of the weld bead 28. However, the control information generation device 33 can have multiple types of characteristic profiles that represent the shape change characteristics of the weld bead 28, such as the layer width and layer cross-sectional area. This allows the control information generation device 33 to consider multiple types of profiles and, while comprehensively considering various characteristics of the weld bead 28, approximate the shape of the layered weld bead 28, that is, the shape of the three-dimensional structure, to the planned shape (simulated shape) based on the welding plan.

[0039] The pseudo-block body X shown in Figure 4 is an example where multiple weld beads 28 are stacked in a single row only. However, most actual three-dimensional structures are not formed by such single rows alone, but rather by multiple pseudo-block bodies X being formed adjacent to each other in the width direction (lateral direction).

[0040] Figure 6 is an explanatory diagram showing a prediction model for predicting bead height, which represents a pseudo-block body obtained by stacking multiple bead models. Figure 6 shows a pseudo-block body W corresponding to the three-dimensional structure described above, where pseudo-block bodies X0, X1, X2, and X3 are arranged in the width direction and formed. The height of each pseudo-block body X0, X1, X2, and X3 may change due to the influence of other pseudo-block bodies (especially adjacent ones).

[0041] The control information generation device 33 then acquires a characteristic profile of the shape change of the weld bead 28 that occurs when the control conditions are changed for the pseudo-block body W. The characteristic profile in this example shows the characteristics of the shape change of the pseudo-block body W, which is formed by stacking multiple adjacent weld beads 28. The additive manufacturing device 11 actually fabricates a three-dimensional structure corresponding to the pseudo-block body W under various control conditions, and the control information generation device 33 measures the actual shape, including its height (or width). Furthermore, the control information generation device 33 compares the measured actual shape of the three-dimensional structure with a simulated shape that simulates the shape of this three-dimensional structure by stacking the bead models (pseudo-block body W) in Figure 6. This allows the control information generation device 33 to extract the difference between the actual shape that better fits the actual three-dimensional structure and the simulated shape.

[0042] Figure 7 is a flowchart showing the steps of the method for fabricating a three-dimensional structure performed by the additive manufacturing apparatus 11 of the embodiment. In this flowchart, steps S1 to S5 also correspond to the processes of the control information generation method performed by the control information generation device 33.

[0043] First, the data acquisition unit 331 of the control information generation device 33 acquires a characteristic profile of the predicted shape of the laminate when multiple weld beads are stacked, based on a welding plan that includes a pseudo-block body (S1). Next, the measurement unit 332 of the control information generation device 33 measures the shape of the actually formed laminate (actual shape) (S2).

[0044] Next, the calculation unit 333 of the control information generation device 33 compares the simulated shape created by bead lamination with the actual shape and calculates the difference between the two (S3). Then, the control information output unit 334 of the control information generation device 33 extracts a correction value to eliminate the difference (S4), and modifies the control information using the extracted correction value (S5).

[0045] The control unit 31 of the welding control device 30 controls the additive manufacturing device 11 according to the corrected control information, that is, the control information output by the control information output unit 334, and the welding device 100 performs arc welding based on the operation of the additive manufacturing device 11 according to this control information to fabricate a three-dimensional structure (S6).

[0046] The welding control device 30 can appropriately control the additive manufacturing device 11 based on the modified control information. Furthermore, the welding device 100 can perform appropriate arc welding using the additive manufacturing device 11 to fabricate a three-dimensional structure that closely resembles the simulated shape.

[0047] According to this embodiment, by utilizing shape prediction based on characteristic profiles, the effort required is significantly reduced compared to preparing a separate table of condition correction amounts through experiments. Furthermore, differences can be corrected more accurately than simply using the results of bead-on-plate (BOP) tests. In addition, appropriate correction amounts can be calculated for various lamination patterns and welding conditions.

[0048] Figure 8 is a graph illustrating a method for eliminating height differences as the number of layers of weld beads 28 increases. Line L1 represents the target planned height in the simulated shape, and heights H1, H2, H3, H4, etc., are planned heights.

[0049] First, the control information generation device 33 sets the actual height H, which is the actual shape, relative to the planned height H1. 11 The difference Δh1 is extracted. Next, the control information generation device 33 determines the next target height H2 by adding the difference Δh1, which is the amount that was lower in the first layer, because the initial planned height H2 is too low. 22 =Outputs the initially planned height H2+Δh1. ​​However, the control information generation device 33 measures the actual height of the second layer H 21 However, it was found that the height was Δh2 lower than the initially planned height H2.

[0050] Thus, when a difference occurs between the welding plan and the actual height of the shape, even if the control information is controlled using a correction value corresponding to the height difference, the difference may not be sufficiently resolved. In other words, a persistent height error may remain.

[0051] Therefore, the control information output unit 334 of the control information generation device 33 sets the target height H in the third layer to be raised by Δh2 from the initially planned height H3. 32 The control information output unit 334 outputs the following: In other words, the control information output unit 334 sets a correction target value that is greater than the difference and outputs the corrected control information according to the correction target value. As a result, the control information generation device 33 sets a target value that is greater than the difference, and can obtain a correction value that contributes sufficiently to correcting the height. This method can be applied not only to correcting the stacking height, but also to the stacking width, stacking cross-sectional area, etc.

[0052] Figure 9 is a graph illustrating other methods for eliminating height differences as the number of layers of weld beads 28 increases. The line L2 represents the target planned height in the simulated shape, and heights H1, H2, H3, H4, H5, H6... are planned heights.

[0053] First, the control information generation device 33 sets the actual height H, which is the actual shape, relative to the planned height H1. 11 Extract the difference Δh1 from the given value.

[0054] Next, the control information generation device 33 determines the next target height H2 by adding the difference Δh1, which is the difference from the first layer, because the initially planned height H2 is too low. 22 =Outputs the initially planned height H2+Δh1. ​​However, the control information generation device 33 measures the actual height of the second layer H 21 However, it was found that the height was Δh2 lower than the initially planned height H2.

[0055] Therefore, the control information output unit 334 of the control information generation device 33, similar to the example in Figure 8, sets the target height H in the third layer to be raised by Δh1 + Δh2 from the initially planned height H3. 32 Outputs.

[0056] However, the control information generation device 33 found through measurement that the actual height H of the third layer is Δh3 lower than the planned height H3 originally planned. Therefore, the control information output unit 334 of the control information generation device 33 aims to increase the height by Δh1 + Δh2 + Δh3 from the planned height H4 originally planned in the fourth layer, and outputs the target height H. 31 As a result, the control information generation device 33 sets a value larger than the difference as the target value, and can obtain a correction value that sufficiently contributes to the correction of the height. In particular, the method shown in FIG. 9 can suppress the accumulation of differences more than the method shown in FIG. 8. This method is applicable not only to the correction of the stacking height but also to the stacking width, the stacking cross-sectional area, and the like. 42

[0057] As described above, the present invention is not limited to the above-described embodiments, and it is also contemplated by the present invention that those skilled in the art can combine each configuration of the embodiments with each other, make changes, and apply them based on the description of the specification and well-known techniques, and these are included in the scope for which protection is sought.

[0058] As described above, the following matters are disclosed in this specification. (1) A control information generation device that generates control information for controlling a layer forming apparatus that forms a three-dimensional structure by laminating layer shapes using a welding bead formed by adding a melted processing material to a processing target surface while moving along a path where a processing position is predetermined based on specified control conditions, a data acquisition unit that acquires a characteristic profile of a shape change of the welding bead that occurs when the control condition is changed, with respect to a pseudo-block body obtained by laminating a plurality of bead models simulating the shape of the welding bead; a measurement unit that measures an actual shape including at least the height or width of the formed three-dimensional structure; an arithmetic unit that compares the simulated shape of the three-dimensional structure simulated by laminating the bead models with the actual shape and extracts the difference between the two shapes; ​A control information output unit that obtains a correction value for the control condition that eliminates the difference from the characteristic profile and outputs the corrected control information according to the correction value, A control information generation device equipped with the following features. This control information generation device allows the shape of the stacked weld beads, i.e., the shape of the three-dimensional structure, to approximate the simulated shape (planned shape) based on the welding plan, while taking into account the characteristics of the weld beads.

[0059] (2) The control information generation device according to (1), wherein the control information output unit sets a correction target value that is greater than the difference and outputs the control information corrected according to the correction target value. According to this control information generation device, a value greater than the difference is set as the target value, and a correction value that sufficiently contributes to height correction can be obtained.

[0060] (3) The control information generating device according to (1) or (2), wherein the characteristic profile shows the characteristics of the shape change of the pseudo-block body formed by stacking a plurality of adjacent weld beads. This control information generation device can extract the difference between the actual shape that better fits the three-dimensional structure and the simulated shape.

[0061] (4) A control information generation device according to any one of (1) to (3), comprising a plurality of characteristic profiles that represent the shape change characteristics including at least the layer height, layer width, or layer cross-sectional area of ​​the weld bead. This control information generation device takes into account multiple types of profiles and comprehensively considers various characteristics of the weld bead, making it possible to approximate the shape of the stacked weld beads, i.e., the shape of the three-dimensional structure, to the simulated shape (planned shape) based on the welding plan.

[0062] (5) A method for generating control information for controlling an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, which is formed by adding molten material to a workpiece surface to create a weld bead while moving the processing position along a predetermined path based on specified control conditions, and thereby creating a layered shape. A data acquisition step to acquire a characteristic profile of the change in the shape of the weld bead that occurs when the control conditions are changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead. A measurement step of measuring the actual shape of the fabricated three-dimensional structure, which includes at least the height or width of the structure, A calculation step of comparing the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracting the difference between the two shapes, A control information output step includes obtaining a correction value for the control condition that eliminates the difference from the characteristic profile and outputting the corrected control information according to the correction value, A control information generation method comprising the following: This control information generation method allows the shape of the stacked weld beads, i.e., the shape of the three-dimensional structure, to approximate the simulated shape (planned shape) based on the welding plan, while taking into account the characteristics of the weld beads.

[0063] (6) A control information generation device described in any one of (1) to (4), A welding control device comprising a control unit that controls the additive manufacturing apparatus according to the results output by the control information generation device. This welding control device allows for the proper control of the additive manufacturing apparatus based on the corrected control information.

[0064] (7) The welding control device described in (6), The aforementioned additive manufacturing apparatus, A welding apparatus equipped with the following features. This welding device allows for the creation of three-dimensional structures that closely resemble the simulated shape by performing appropriate arc welding using an additive manufacturing device.

[0065] (8) A control information generation program that generates control information for an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, by moving the processing position along a predetermined path based on specified control conditions, and applying molten processing material to the surface of the workpiece to form a weld bead, thereby creating a layered shape. A data acquisition step to acquire a characteristic profile of the change in the shape of the weld bead that occurs when the control conditions are changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead. A measurement step of measuring the actual shape of the fabricated three-dimensional structure, which includes at least the height or width of the structure, A calculation step of comparing the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracting the difference between the two shapes, A control information output step includes obtaining a correction value for the control condition that eliminates the difference from the characteristic profile and outputting the corrected control information according to the correction value, A control information generation program that causes a computer to execute commands. According to this control information generation program, the shape of the stacked weld beads, i.e., the shape of the three-dimensional structure, can be approximated to a simulated shape (planned shape) based on the welding plan, while taking into account the characteristics of the weld beads. [Explanation of symbols]

[0066] 11. Additive Manufacturing Equipment 15 Welding Torch 17 Welding robots 21 Robot Controller 23 Filler metal supply section 25 Welding power supply 30 Welding control device 31 Control Unit 32 Shape Sensors 33 Control Information Generation Device 100 welding equipment 331 Data Acquisition Unit 332 Measurement Unit 333 Arithmetic section 334 Control Information Output Unit M Filler material (processing material, welding wire)

Claims

1. A control information generation device that generates control information for controlling an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, which is formed by adding molten material to a workpiece surface to create a weld bead while moving the processing position along a predetermined path based on a specified welding speed, and thereby creating a layered shape. A data acquisition unit that acquires a characteristic profile of the change in the shape of the weld bead that occurs when the welding speed is changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead, A measuring unit that measures the actual shape of the fabricated three-dimensional structure, including at least the height or width of the structure, A calculation unit that compares the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracts the difference between the two shapes, A control information output unit that determines a correction value for the welding speed to eliminate the difference from the characteristic profile and outputs the corrected control information according to the correction value, Equipped with, A control information generation device in which the specified welding speed is changed based on the difference between the simulated shape and the actual shape, so as to bring the difference closer to zero.

2. The control information output unit sets a correction target value that is greater than the difference in accordance with the increase in the number of layers to be stacked, and outputs the control information corrected according to the correction target value. The control information generation device according to claim 1.

3. The characteristic profile shows the characteristics of the shape change of the pseudo-block body formed by stacking multiple adjacent weld beads. A control information generation device according to claim 1 or 2.

4. The system comprises multiple characteristic profiles that represent the shape change characteristics, including at least one of the layer height, layer width, or layer cross-sectional area of ​​the weld bead. A control information generation device according to any one of claims 1 to 3.

5. A method for generating control information to control an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, which is formed by adding molten material to a workpiece surface to create a weld bead, while moving the processing position along a predetermined path based on a specified welding speed, thereby creating a layered shape. A data acquisition step to acquire a characteristic profile of the change in the shape of the weld bead that occurs when the welding speed is changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead, A measurement step of measuring the actual shape of the fabricated three-dimensional structure, which includes at least the height or width of the structure, A calculation step of comparing the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracting the difference between the two shapes, A control information output step includes determining a correction value for the welding speed that eliminates the aforementioned difference from the characteristic profile, and outputting the control information corrected according to the correction value, Equipped with, A control information generation method in which, in the control information output step, the specified welding speed is changed based on the difference between the simulated shape and the actual shape, so as to bring the difference closer to zero.

6. A control information generation device according to any one of claims 1 to 4, A welding control device comprising a control unit that controls the additive manufacturing apparatus according to the results output by the control information generation device.

7. The welding control device according to claim 6, The aforementioned additive manufacturing apparatus, A welding apparatus equipped with the following features.

8. A control information generation program that generates control information for an additive manufacturing apparatus that creates a three-dimensional structure by stacking layers, by forming a layered shape using a weld bead formed by adding molten material to a workpiece surface while moving the processing position along a predetermined path based on a specified welding speed, A data acquisition step to acquire a characteristic profile of the change in the shape of the weld bead that occurs when the welding speed is changed, for a pseudo-block body obtained by stacking multiple bead models that simulate the shape of the weld bead, A measurement step of measuring the actual shape of the fabricated three-dimensional structure, which includes at least the height or width of the structure, A calculation step of comparing the simulated shape obtained by stacking the bead models of the three-dimensional structure with the actual shape and extracting the difference between the two shapes, A control information output step includes determining a correction value for the welding speed that eliminates the aforementioned difference from the characteristic profile, and outputting the control information corrected according to the correction value, Have the computer run it, In the control information output process, a control information generation program modifies the specified welding speed based on the difference between the simulated shape and the actual shape, so as to bring the difference closer to zero.

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