SYSTEM FOR MANUFACTURING FORMED ARTICLE, CONTROL APPARATUS FOR MANUFACTURING FORMED ARTICLE, METHOD FOR CONTROLLING MANUFACTURING FORMED ARTICLE, AND PROGRAM

Abstract

To reduce such a possibility that the postures of a first formation device and a second formation device cannot be maintained.SOLUTION: A manufacturing system of a molding comprises: a first formation device which forms a bead obtained by melting and solidifying a filler material; a second formation device which forms a bead obtained by melting and solidifying a filler material; an adjustment device which adjusts the position or posture of a base material; and a control device which controls the first formation device, the second formation device, and the adjustment device so as to manufacture a molding by forming the bead on the base material. The control device decides a first control change amount of the first formation device, a second control change amount of the second formation device, and a third control change amount of the adjustment device such that both of the first control change amount and the second control change amount become smaller than the greater one of a first correction amount and a second correction amount, on the basis of the first correction amount of a formation condition of the first formation device and the second correction amount of a formation condition of the second formation device.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a manufacturing system for a shaped object, a manufacturing control device for a shaped object, a manufacturing control method for a shaped object, and a program. [Background technology]

[0002] Patent Document 1 describes an industrial robot system in which a system control device periodically reads and compares the positions of two robots to determine whether each robot is progressing quickly or slowly, and manages the progress of the two robots over time by instructing each robot's individual control device to slightly increase or decrease the work speed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 2686839 Summary of the Invention [Problem to be solved by the invention]

[0004] The control change amount of the first forming device, the control change amount of the second forming device, and the control change amount of the adjusting device that adjusts the position or attitude of the base material may be determined based on the correction amount of the forming conditions of the first and second forming devices that form a bead by melting and solidifying a filler metal. In this case, if a configuration that reduces the control change amount of the first forming device and the control change amount of the second forming device is not adopted, it may be impossible to maintain the attitudes of the first forming device and the second forming device.

[0005] The object of the present invention is to reduce the possibility that the posture of the first forming device and the second forming device cannot be maintained when determining the control change amount of the first forming device, the control change amount of the second forming device, and the control change amount of the adjustment device that adjusts the position or posture of the base material based on the correction amount of the forming conditions of the first and second forming devices that form a bead by melting and solidifying filler metal. [Means for solving the problem]

[0006] With this objective in mind, the present invention provides a system for manufacturing a shaped object, comprising: a first forming device that forms a bead by melting and solidifying a filler material; a second forming device that forms a bead by melting and solidifying the filler material; an adjustment device that adjusts the position or attitude of a base material; and a control device that controls the first forming device, the second forming device, and the adjustment device to manufacture a shaped object by forming a bead on the base material, wherein the control device determines a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for the adjustment device based on a first correction amount for the forming conditions of the first forming device and a second correction amount for the forming conditions of the second forming device, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount.

[0007] The present invention also provides a control device for manufacturing a molded object, which includes: an acquisition unit that acquires a first correction amount for the forming conditions of a first forming device that forms a bead by melting and solidifying a filler material, and a second correction amount for the forming conditions of a second forming device that forms a bead by melting and solidifying the filler material; a determination unit that determines a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for an adjustment device that adjusts the position or attitude of the base material based on the first correction amount and the second correction amount, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount; and a control unit that controls the first forming device, the second forming device, and the adjustment device using the first control change amount, the second control change amount, and the third control change amount so as to manufacture a molded object by forming a bead on the base material. The determination unit may determine the first control change amount and the second control change amount based on a difference between the first correction amount and the second correction amount. In this case, the first correction amount may be a correction amount for a bead formation speed of the first forming device, and the second correction amount may be a correction amount for a bead formation speed of the second forming device. The first correction amount may be a correction amount for a torch position of the first forming device, and the second correction amount may be a correction amount for a torch position of the second forming device. The manufacturing control device for a molded object may further include a determination unit that determines whether a first influence amount of the first control change amount on the first formation device is smaller than a first threshold and a second influence amount of the second control change amount on the second formation device is smaller than a second threshold. In this case, the first influence amount may be a movement amount of a predetermined portion of the first formation device, and the second influence amount may be a movement amount of a predetermined portion of the second formation device. The first influence amount may be a distance between the predetermined portion of the first formation device and a singular point, and the second influence amount may be a distance between the predetermined portion of the second formation device and the singular point. The determination unit may determine the first threshold based on a range within which a moving device that moves the first formation device can move the first formation device.

[0008] Furthermore, the present invention also provides a method for controlling the production of a shaped object, including: an acquisition step in which a computer acquires a first correction amount for the forming conditions of a first forming device that forms a bead by melting and solidifying a filler material, and a second correction amount for the forming conditions of a second forming device that forms a bead by melting and solidifying the filler material; a determination step in which the computer determines a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for an adjustment device that adjusts the position or attitude of the base material based on the first correction amount and the second correction amount, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount; and a control step in which the computer controls the first forming device, the second forming device, and the adjustment device using the first control change amount, the second control change amount, and the third control change amount so as to produce a shaped object by forming a bead on the base material.

[0009] Furthermore, the present invention also provides a program for causing a computer to realize the following functions: a function for acquiring a first correction amount for the forming conditions of a first forming device that forms a bead by melting and solidifying a filler metal, and a second correction amount for the forming conditions of a second forming device that forms a bead by melting and solidifying a filler metal; a function for determining, based on the first correction amount and the second correction amount, a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for an adjustment device that adjusts the position or attitude of the base material, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount; and a function for controlling the first forming device, the second forming device, and the adjustment device using the first control change amount, the second control change amount, and the third control change amount to manufacture a shaped object by forming a bead on the base material. [Effects of the Invention]

[0010] According to the present invention, when determining the control change amount of the first forming device, the control change amount of the second forming device, and the control change amount of the adjustment device that adjusts the position or attitude of the base material based on the correction amount of the forming conditions of the first and second forming devices that form a bead by melting and solidifying filler metal, the possibility of the attitude of the first forming device and the second forming device being unable to be maintained is reduced. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram showing a schematic configuration example of a metal additive manufacturing system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram illustrating an example of a hardware configuration of a control device according to an embodiment of the present invention. [Figure 3] 10(a) and 10(b) are diagrams showing that when the position of one welding torch is fixed and the angular velocity of the positioner is changed, the welding position and welding direction of the other welding torch change significantly. [Figure 4] 10(a) and 10(b) are diagrams showing a first example of distribution of the correction amount obtained by feedback calculation to two welding torches and a positioner. FIG. [Figure 5] 10(a) and 10(b) are diagrams showing a second example of distribution of the correction amount obtained by feedback calculation to two welding torches and a positioner. [Figure 6] FIG. 10 is a diagram showing a calculation method for distributing a correction amount to two welding torches and a positioner. [Figure 7] FIG. 1 is a diagram illustrating an example of a functional configuration of a stacking planning device according to an embodiment of the present invention. [Figure 8] FIG. 2 is a diagram illustrating an example of a functional configuration of a control device according to an embodiment of the present invention. [Figure 9] 1 is a flowchart showing an example of the operation of the stacking planning device according to the embodiment of the present invention. [Figure 10] 4 is a flowchart showing the contents of a control program correction process for cooperative control executed by a control device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0013] [Configuration of Metal Additive Manufacturing System] In this embodiment, the metal additive manufacturing system is assumed to be a system that can improve productivity even for precision manufacturing by using multiple welding robots and moving welding torches individually. For example, a single welding robot cannot weld a weld line that passes near a singular point. However, by flexibly sharing the work among multiple welding robots, it becomes possible to weld a part without the weld line passing near the singular point. Below, such a metal additive manufacturing system will be described using an example in which two welding robots are used.

[0014] FIG. 1 is a diagram showing a schematic configuration example of a metal additive manufacturing system 1 according to this embodiment. As shown in the figure, the metal additive manufacturing system 1 includes welding robots (manipulators) 10a and 10b, a positioner 20, a CAD device 25, a stacking planning device 30, and a control device 50. The stacking planning device 30 writes a control program for controlling the welding robots 10a and 10b to a removable recording medium 70 such as a memory card, and the control device 50 is capable of reading the control program written to the recording medium 70.

[0015] The welding robot 10a includes an arm 11a with multiple joints and performs welding operations by operating in accordance with a control program loaded by a control device 50. The welding robot 10a also has a welding torch 13a attached to the tip of the arm 11a via a wrist 12a for forming the additive manufacturing object 100. In the case of the metal additive manufacturing system 1, the welding robot 10a moves the welding torch 13a while melting a mild steel filler material (wire) 14a to manufacture the additive manufacturing object 100. Specifically, the welding torch 13a supplies the filler material 14a and generates an arc while flowing a shielding gas to melt and solidify the filler material 14a, and then layers multiple weld beads (hereinafter simply referred to as "beads") 102 on a base material 101 to manufacture the additive manufacturing object 100. Note that although an arc is used as a heat source for melting the filler material 14a here, a laser or plasma may also be used. The welding robot 10a also includes a feeder for feeding the filler material 14a, but the description thereof will be omitted. The welding robot 10a also includes a shape sensor 15a at the tip of the arm 11a. The shape sensor 15a may be any sensor capable of measuring the shape of the layered beads 102. For example, the shape sensor 15a may be a laser sensor that acquires height data from the reflected light of an irradiated laser beam. Alternatively, the shape sensor 15a may be a camera for three-dimensional shape measurement. In this embodiment, a welding robot 10a is provided as an example of a first forming device that forms a bead by melting and solidifying a filler material.

[0016] Welding robot 10b has the same configuration as welding robot 10a, and therefore its description will be omitted. However, the reference numerals indicating the parts of welding robot 10b will have a suffix "b" added to them instead of the suffix "a" added to the reference numerals of the parts of welding robot 10a. Note that if there is no need to distinguish between welding robot 10a and its parts and welding robot 10b and its parts, this suffix may not be added. In this embodiment, a welding robot 10b is provided as an example of a second forming device that forms a bead by melting and solidifying a filler metal.

[0017] The positioner 20 holds the base material 101 and rotates the base material 101 so that a bead 102 can be formed on the base material 101 even if the positions of the welding torches 13a and 13b are fixed. In this embodiment, a positioner 20 is provided as an example of an adjustment device for adjusting the position or posture of the base material.

[0018] The CAD device 25 uses a computer to design a model, and has the function of storing three-dimensional data obtained by the design (hereinafter referred to as "three-dimensional CAD data").

[0019] The lamination planning device 30 creates a lamination plan for the layered object 100 based on the three-dimensional CAD data held by the CAD device 25. That is, it determines the trajectories of the welding torches 13a and 13b and also determines the welding conditions for welding by the welding robots 10a and 10b. It then generates a control program for controlling the welding robots 10a and 10b so as to form the bead 102 along the determined trajectories under the determined welding conditions, and outputs this control program to the recording medium 70.

[0020] The control device 50 reads and stores a control program from the recording medium 70. By running this control program, the welding robots 10a and 10b are controlled to form the bead 102 according to the stacking plan created by the stacking planning device 30, that is, along the trajectory determined by the stacking planning device 30 and under the welding conditions determined by the stacking planning device 30. In this embodiment, a control device 50 is provided as an example of a control device that controls the first forming device, the second forming device, and the adjustment device to manufacture a molded object by forming a bead on a base material.

[0021] Here, the welding robots 10a and 10b are configured to manufacture the additively manufactured object 100 by stacking the beads 102 on the base material 101, but this is not limiting. The welding robots 10a and 10b may also perform, for example, multi-layer welding or build-up welding in a groove.

[0022] [Control device hardware configuration] FIG. 2 is a diagram illustrating an example of the hardware configuration of the control device 50. As shown in FIG. As shown in the figure, the control device 50 is realized by, for example, a general-purpose PC (Personal Computer) or the like, and includes a CPU 51 as a computing means, a main memory 52 as a storage means, and a magnetic disk device (HDD: Hard Disk Drive) 53. Here, the CPU 51 executes various programs such as an OS (Operating System) and application software, and realizes each function of the control device 50. The main memory 52 is a storage area that stores various programs and data used for executing the programs, and the HDD 53 is a storage area that stores input data for the various programs, output data from the various programs, and the like. The control device 50 also includes a communication I / F 54 for communicating with the outside, a display mechanism 55 including a video memory, a display, etc., an input device 56 including a keyboard, a mouse, etc., and a driver 57 for reading and writing data from and to the recording medium 70. Note that Fig. 2 merely illustrates an example of a hardware configuration in which the control device 50 is realized by a computer system, and the control device 50 is not limited to the configuration shown in the figure.

[0023] 2 can also be regarded as the hardware configuration of the stacking planning device 30. However, when describing the stacking planning device 30, the CPU 51, main memory 52, magnetic disk device 53, communication I / F 54, display mechanism 55, input device 56, and driver 57 in FIG. 2 will be expressed as CPU 31, main memory 32, magnetic disk device 33, communication I / F 34, display mechanism 35, input device 36, and driver 37, respectively.

[0024] [Background and Overview of the Present Embodiment] When the additive manufacturing system 1 having such a configuration is used to manufacture the additive manufacturing object 100, welding may not be performed as planned due to instantaneous fluctuations in the welding environment or during welding. In such cases, in order to realize the desired shape of the additive manufacturing object 100, it is necessary to change the welding conditions, such as the welding speed, using feedback (FB) control. However, when feedback control is performed, the positions of welding torches 13a and 13b and the postures of welding robots 10a and 10b cannot be maintained, which may result in changes in the shape of bead 102 or deterioration of workability.

[0025] This will be specifically explained below using the welding speed as an example of a welding condition. For example, if the position of welding torch 13b is fixed and the angular velocity (or rotational speed) of positioner 20 is changed, the welding position (and welding speed) and welding direction of welding torch 13a will change significantly.

[0026] 3(a) and (b) are diagrams showing this. Here, it is assumed that a correction amount for the welding speed is calculated by feedback calculation so that the height of the bead 102 matches the planned value. In this example, it is assumed that the positioner 20 rotates counterclockwise, and this rotation direction is the positive direction. The distance from the center of the positioner 20 to the welding position by the welding torches 13a and 13b is defined as r. As shown in Figure 3(a), let us assume that the feedback calculation results in fixing welding torches 13a and 13b, leaving the relative velocity of positioner 20 relative to welding torch 13a unchanged, and increasing the relative velocity of positioner 20 relative to welding torch 13b by Δv. Then, as shown in Figure 3(b), it becomes necessary to increase the angular velocity of positioner 20 by Δv / r. Therefore, in order to fix the relative position of welding torch 13a relative to positioner 20, it is necessary to move welding torch 13a in the forward direction at velocity Δv. In this case, it may be necessary to change the posture of welding torch 13a in accordance with the movement of welding torch 13a to maintain welding stability. However, due to limitations on the movable range of welding robot 10a, a problem occurs in that it becomes difficult to sufficiently change the posture when the movement amount of welding torch 13a is large.

[0027] Therefore, in this embodiment, the correction amount obtained by feedback calculation is distributed to welding torches 13a and 13b and positioner 20, and the control change amount is used.

[0028] 4(a) and (b) are diagrams showing a first example of such distribution of correction amounts. Again, it is assumed that the correction amount for the welding speed is calculated by feedback calculation to make the height of the bead 102 match the planned value. Also in this example, it is assumed that the positioner 20 rotates counterclockwise, and the direction of rotation is the positive direction. The distance from the center of the positioner 20 to the welding position by the welding torches 13a and 13b is defined as r. As shown in Fig. 4(a), as a result of the feedback calculation, it is assumed that welding torches 13a and 13b are fixed, the relative velocity of positioner 20 with respect to welding torch 13a is not changed, and the relative velocity of positioner 20 with respect to welding torch 13b is increased by Δv, as in Fig. 3(a). Then, in Fig. 4(b), the angular velocity of positioner 20 is increased by Δv / 2r, welding torch 13a is moved in the positive direction at a velocity Δv / 2, and welding torch 13b is moved in the negative direction at a velocity Δv / 2.

[0029] 5(a) and (b) are diagrams showing a second example of such distribution of correction amounts. This second example is a generalization of the first example described above. Here, too, it is assumed that the correction amount for the welding speed is calculated by feedback calculation so that the height of the bead 102 matches the planned value. Also in this example, it is assumed that the positioner 20 rotates counterclockwise, and the rotation direction is the positive direction. The distance from the center of the positioner 20 to the welding position by the welding torches 13a and 13b is defined as r. As shown in Figure 5(a), let us assume that the feedback calculation results in fixing welding torches 13a and 13b, increasing the relative velocity of positioner 20 with respect to welding torch 13a by Δv1, and increasing the relative velocity of positioner 20 with respect to welding torch 13b by Δv2. Then, as shown in Figure 5(b), the angular velocity of positioner 20 is increased by (Δv1 + Δv2) / 2r, moving welding torch 13a in the forward direction at a velocity (Δv2 - Δv1) / 2, and moving welding torch 13b in the negative direction at a velocity (Δv2 - Δv1) / 2. The arrows in the figure indicate the direction of movement of welding torches 13a and 13b when Δv1 < Δv2 is assumed, and are reversed when Δv2 > Δv1 is assumed. This reduces changes in the angles of the welding robots 10a and 10b relative to the layered object 100 and in the attitude angles of the welding robots 10a and 10b, thereby reducing the amount of movement of the welding robots 10a and 10b.

[0030] Here, a calculation method for distributing the correction amounts shown in FIGS. 4(a), 4(b) and 5(a), 5(b) to welding torches 13a, 13b and positioner 20 will be described in detail. FIG. 6 shows such a calculation method. Here, positioner 20 is assumed to rotate counterclockwise, and the rotation direction is assumed to be the positive direction. Also, the angular velocity of positioner 20 is assumed to be ω, the movement speed of welding torch 13a is assumed to be t1, and the movement speed of welding torch 13b is assumed to be t2. The radius from the center of positioner 20 to the welding position by welding torch 13a is assumed to be r1, and the radius from the center of positioner 20 to the welding position by welding torch 13b is assumed to be r2. The target welding speed of welding torch 13a, i.e., the target relative speed of positioner 20 with respect to welding torch 13a, is assumed to be v1, and the target welding speed of welding torch 13b, i.e., the target relative speed of positioner 20 with respect to welding torch 13b, is assumed to be v2. The movement speeds of welding torches 13a and 13b may be expressed as angular velocities ω1 and ω2 of welding torches 13a and 13b around the center of positioner 20, but below they will be expressed as movement speeds t1 and t2 of welding torches 13a and 13b (t1=r1ω1, t2=r2ω2).

[0031] The target welding speeds v1 and v2 of the welding torches 13a and 13b satisfy the following formula. v1=r1ω-t1 v2=r2ω-t2 Here, the case where r1=r2=r will be described in detail. First, the combination where t1=0 (hereinafter referred to as "pattern 1") is as follows. t1=0,t2=v1-v2,ω=v1 / r Next, the combination where t2=0 (hereinafter referred to as "pattern 2") is as follows. t1=v2-v1,t2=0,ω=v2 / r Furthermore, when v1 × v2 > 0 (when welding in the same direction), the combination in which |t1| and |t2| are equally small (hereinafter referred to as "pattern 3") is as follows. t1=(v2-v1) / 2,t2=(v1-v2) / 2,ω=(v1+v2) / 2r In patterns 1 and 2, it is sufficient to correct the trajectory of either welding robot 10a or 10b, but there are restrictions on the operating posture. In contrast, in pattern 3, it is possible to perform welding over a longer phase in one pass based on the rotation distance.

[0032] Here, let us assume that the planned speeds are v1 = v2 = v0. In this case, it is easier to fix welding torches 13a and 13b and rotate positioner 20, since this allows for more than one rotation. The state at this time (hereinafter referred to as "state 1") is as follows. t1=0,t2=0,ω=v0 / r

[0033] First, consider the case where v2 is changed to v0 + Δv by feedback control (as shown in Figures 4(a) and (b)). In this case, the change in speed relative to State 1 is calculated as follows for each of the above patterns: Pattern 1 t1=0,t2=-Δv,ω=v0 / r (The change amount is dt1=0, dt2=-Δv, dω=0) Pattern 2 t1=Δv,t2=0,ω=v0 / r+Δv / r (The amount of change is dt1=Δv, dt2=0, dω=Δv / r) Pattern 3 t1=Δv / 2,t2=-Δv / 2,ω=v0 / r+Δv / 2r (The amount of change is dt1=Δv / 2, dt2=-Δv / 2, dω=Δv / 2r) The amount of change in this pattern 3 is the amount of change shown in FIG.

[0034] Next, consider the case where v1 is changed to v0 + Δv1 and v2 is changed to v0 + Δv2 by feedback control (as shown in Figures 5(a) and (b)). In this case, the change in speed for State 1 is calculated as follows for each of the above patterns. Pattern 1 t1=0,t2=Δv1-Δv2,ω=v0 / r+Δv1 / r (The amount of change is dt1=0, dt2=Δv1-Δv2, dω=Δv1 / r) Pattern 2 t1=Δv2-Δv1,t2=0,ω=v0 / r+Δv2 / r (The amount of change is dt1=Δv2-Δv1, dt2=0, dω=Δv2 / r) Pattern 3 t1=(Δv2-Δv1) / 2,t2=-(Δv2-Δv1) / 2,ω=v0 / r+(Δv1+Δv2) / 2r (The amount of change is dt1=(Δv2-Δv1) / 2, dt2=-(Δv2-Δv1) / 2, dω=(Δv1+Δv2) / 2r) The amount of change in this pattern 3 is the amount of change shown in FIG. 5(b).

[0035] [Functional configuration of stacking planning device] 7 is a diagram showing an example of the functional configuration of the stacking planning device 30 in this embodiment. As shown in the figure, the stacking planning device 30 in this embodiment includes a CAD data acquisition unit 41, a CAD data division unit 42, a stacking planning unit 43, a control program generation unit 44, a planned value acquisition unit 45, and an information output unit 46.

[0036] The CAD data acquisition unit 41 acquires, from the CAD device 25, three-dimensional CAD data that represents the three-dimensional shape of the layered object 100. The CAD data dividing unit 42 generates a plurality of layer shape data each representing the shape of each layer by dividing (slicing) the three-dimensional CAD data acquired by the CAD data acquiring unit 41 into a plurality of layers. At this time, the CAD data dividing unit 42 may convert the three-dimensional CAD data into an internal format that makes it easier to divide the data into a plurality of layers.

[0037] The lamination planning unit 43 generates a lamination plan including welding conditions and arc target positions for depositing the bead 102 that match the height and width of each layer of the multiple layer shape data generated by the CAD data division unit 42. To generate such a lamination plan, a model approximating the cross-sectional shape of the bead 102 is required, in addition to the height and width of the bead 102. These may be estimated by calculation based on actual measurements from measurement experiments or the cross-sectional area of ​​the deposited metal. In this embodiment, bead-on-plate welding and vertical lamination of several layers are performed while varying the deposition amount under several conditions of welding speed and wire feed speed, and the results of measuring the height and width per layer under each condition are stored in a database. Then, a welding speed and deposition amount that satisfy the desired height and width are selected during lamination, and the estimated shape of each layer is calculated as needed from the measurement results, and the arc target position is determined. The calculation method for calculating the weld cross-section may be changed depending on the material of the filler metal 14 and the shape of the already deposited portion. Lamination including the molded object is planned using this calculation method.

[0038] The control program generating unit 44 generates a control program for controlling the welding robots 10a and 10b so that the welding robots 10a and 10b perform welding in accordance with the lamination plan generated by the lamination plan unit 43. The planned value acquisition unit 45 acquires planned values ​​from the stacking plan generated by the stacking plan unit 43. The planned values ​​include a planned value for the height of the beads 102 formed by the welding robots 10a and 10b, a planned value for the stacking position, and the like. The information output unit 46 outputs information including the control program generated by the control program generation unit 44 and the planned value acquired by the planned value acquisition unit 45 to the recording medium 70.

[0039] Here, the planned value acquisition unit 45 acquires the planned value from the stacking planning unit 43 and notifies the information output unit 46 of the planned value separately from the control program, but this is not limiting. For example, the planned value acquisition unit 45 may acquire the planned value from the control program generated by the control program generation unit 44 and notify the information output unit 46 of the planned value separately from the control program. Alternatively, the planned value acquisition unit 45 may acquire the planned value from the stacking planning unit 43 and include the planned value in the control program to notify the information output unit 46.

[0040] [Control device functional configuration] 8 is a diagram showing an example of the functional configuration of the control device 50 according to this embodiment. As shown in the figure, the control device 50 according to this embodiment includes an information acquisition unit 61, a control program storage unit 62, a control program execution unit 63, a planned value storage unit 64, a performance value acquisition unit 65, a correction amount acquisition unit 66, a correction amount distribution unit 67, an influence amount evaluation unit 68, and a control program correction unit 69.

[0041] The information acquisition unit 61 acquires information recorded on the recording medium 70. This information includes a control program and planned values. The control program storage unit 62 stores the control program from among the information acquired by the information acquisition unit 61. The control program execution unit 63 reads and executes the control program stored in the control program storage unit 62. As a result, the control program execution unit 63 controls the welding robots 10a and 10b and the positioner 20 so as to form the bead 102 in accordance with the lamination plan generated by the lamination plan unit 43. The planned value storage unit 64 stores the planned value among the information acquired by the information acquisition unit 61. The actual value acquiring unit 65 acquires actual values ​​related to the shape of the bead 102 formed by the welding robots 10a and 10b. The following description will be given taking as an example a case where the actual value acquiring unit 65 acquires the actual height of the bead 102 or the actual layering position of the bead 102 as the actual value. For example, the actual value acquiring unit 65 may acquire the actual height of the bead 102 from the shape sensors 15a and 15b. Alternatively, the actual height of the bead 102 may be acquired based on a current value during welding obtained from an ammeter (not shown) or a voltage value during welding obtained from a voltmeter (not shown).

[0042] The correction amount acquisition unit 66 acquires correction amounts for the additive manufacturing conditions of the welding robots 10a and 10b from the actual results values ​​related to additive manufacturing of the welding robots 10a and 10b acquired by the actual result value acquisition unit 65.

[0043] For example, the correction amount acquiring unit 66 considers the difference between the planned height of the bead 102 stored in the planned value storage unit 64 and the actual height of the bead 102 acquired by the actual value acquiring unit 65 as the amount to be corrected, and calculates the conditions necessary for height correction. If the actual height of the bead 102 is slightly higher than the planned height of the bead 102, the welding speed is increased to control the height of the bead 102 to be lower. If the actual height of the bead 102 is slightly lower than the planned height of the bead 102, the welding speed is decreased to control the height of the bead 102 to be higher. In this case, the correction amount acquiring unit 66 acquires correction amounts Δv1 and Δv2 for the welding speeds of the welding robots 10a and 10b. The correction amount acquiring unit 66 may acquire the correction amounts Δv1 and Δv2 by, for example, acquiring the relationship between the welding speed and the shape of the bead 102 through an element test such as a BOP test and storing the relationship in a database. In this embodiment, a correction amount Δv1 is used as an example of a first correction amount for the formation conditions of the first formation device, and a correction amount Δv2 is used as an example of a second correction amount for the formation conditions of the second formation device. In this embodiment, a correction amount acquisition unit 66 is provided as an example of an acquisition unit that acquires the first correction amount and the second correction amount. In this embodiment, a correction amount Δv1 is used as an example of a first correction amount, which is a correction amount for the bead formation speed of the first forming device, and a correction amount Δv2 is used as an example of a second correction amount, which is a correction amount for the bead formation speed of the second forming device.

[0044] Alternatively, correction amount acquiring unit 66 may consider the deviation between the planned layer position of bead 102 stored in planned value storage unit 64 and the actual layer position of bead 102 acquired by actual value acquiring unit 65 as the amount to be corrected, and calculate the conditions necessary for layer position correction. In this case, correction amount acquiring unit 66 may acquire correction amounts Δz1 and Δz2 for the heights of welding torches 13a and 13b. In this embodiment, a correction amount Δz1 is used as an example of a first correction amount for the formation conditions of the first formation device, and a correction amount Δz2 is used as an example of a second correction amount for the formation conditions of the second formation device. In this embodiment, a correction amount acquisition unit 66 is provided as an example of an acquisition unit that acquires the first correction amount and the second correction amount. In this embodiment, a correction amount Δz1 is used as an example of a first correction amount, which is a correction amount for the position of the torch of the first forming device, and a correction amount Δz2 is used as an example of a second correction amount, which is a correction amount for the position of the torch of the second forming device.

[0045] The correction amount distributor 67 distributes the correction amount acquired by the correction amount acquisition unit 66 to the welding robots 10a and 10b and the positioner 20.

[0046] For example, correction amount distributor 67 allocates correction amounts Δv1 and Δv2 for the welding speeds of welding robots 10a and 10b, acquired by correction amount acquirer 66, to welding robots 10a and 10b and positioner 20. Here, the control amount before the allocation of the correction amounts is set to (0, 0, v0 / r), and the control amount after the allocation of the correction amounts is set to (X1, X2, v0 / r+X3). Of the three parameters in parentheses for the control amounts, the first parameter indicates the welding speed of welding robot 10a, the second parameter indicates the welding speed of welding robot 10b, and the third parameter indicates the angular velocity of positioner 20. The combination of X1, X2, and X3 is not limited to one, and multiple combinations are also possible. A specific example of the control change amounts (X1, X2, X3) is calculated as ((Δv2-Δv1) / 2, -(Δv2-Δv1) / 2, (Δv1+Δv2) / 2r) as shown in Figures 5(a) and 5(b). This specific example is calculated to reduce the correction amount for the welding speed of welding robots 10a and 10b, and can therefore be said to be a suitable example of the control change amounts. In this embodiment, it is possible to reduce the amount of change in the welding speed of each of welding robots 10a and 10b compared to when the welding speeds of welding robots 10a and 10b are directly corrected based on the correction amount, and as a result, it is possible to suppress the degree of change in the posture of welding robots 10a and 10b.

[0047] Alternatively, correction amount distributor 67 allocates correction amounts Δz1 and Δz2 for the heights of welding torches 13a and 13b acquired by correction amount acquirer 66 to welding robots 10a and 10b and positioner 20. Here, the control amount before the correction amounts are allocated is set to (0, 0, z0), and the control amount after the correction amounts are allocated is set to (X1, X2, z0+X3). Of the three parameters in parentheses for the control amount, the first parameter indicates the height of welding torch 13a, the second parameter indicates the height of welding torch 13b, and the third parameter indicates the height of the stage of positioner 20. The combination of X1, X2, and X3 is not limited to one, and multiple combinations are also possible. As a specific example of the control change amounts (X1, X2, X3), ((Δz2-Δz1) / 2, -(Δz2-Δz1) / 2, (Δz1+Δz2) / 2) are calculated in the same manner as above. This specific example is calculated to reduce the amount of correction for the heights of welding torches 13a and 13b, and can therefore be said to be a suitable example of the control change amounts. In this embodiment, it is possible to reduce the amount of change in the positions of welding torches 13a and 13b compared to when the position of welding torch 13 is directly corrected based on the correction amount, and as a result, it is possible to suppress the degree of change in the posture of welding robots 10a and 10b.

[0048] In this embodiment, a control change amount X1 is used as an example of a first control change amount for the first forming device, a control change amount X2 is used as an example of a second control change amount for the second forming device, and a control change amount X3 is used as an example of a third control change amount for the adjustment device. In this embodiment, a correction amount distributor 67 is provided as an example of a determiner that determines the first control change amount, the second control change amount, and the third control change amount based on the first correction amount and the second correction amount so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount. In addition, in a suitable example of the control change amount obtained by distributing the correction amount by the correction amount distributor 67 to the welding robots 10a, 10b and the positioner 20, the first parameter and the second parameter include (Δv2-Δv1) or (Δz2-Δz1). In this sense, the correction amount distributor 67 can be said to be an example of a determiner that determines the first control change amount and the second control change amount based on the difference between the first correction amount and the second correction amount.

[0049] Influence amount evaluation unit 68 evaluates the influence on the posture of welding robots 10a, 10b of control change amounts X1 to X3 after correction amount distribution unit 67 distributes the correction amounts. Influence amount evaluation unit 68 may use, as the influence on the posture of welding robots 10a, 10b, the amount of movement of a predetermined portion of welding robots 10a, 10b, the distance between a predetermined portion of welding robots 10a, 10b and a singular point, etc. The predetermined portion of welding robots 10a, 10b includes the tips of welding torches 13a, 13b, the joints of welding robots 10a, 10b, etc.

[0050] First, an example will be described in which the movement amounts of the tips of welding torches 13a and 13b are evaluated. The movement amounts of welding torches 13a and 13b are calculated as X1·T1 and X2·T2, respectively, based on the control change amounts X1 and X2 after the correction amount distribution unit 67 distributes the correction amount and the stack times T1 and T2 of the passes of welding robot 10. Influence amount evaluation unit 68 then compares these movement amounts with control reference values ​​L1 and L2, respectively. These control reference values ​​L1 and L2 may be set arbitrarily depending on the performance and management conditions of welding robots 10a and 10b. If the movement amount X1·T1 is below control reference value L1 and the movement amount X2·T2 is below control reference value L2, the operation of welding robots 10a and 10b will be completed within the range of motion even when the distributed control change amounts are used. Conversely, if the movement amount X1·T1 is equal to or greater than the control reference value L1, or if the movement amount X2·T2 is equal to or greater than the control reference value L2, using the distributed control change amount will cause welding torches 13a, 13b to exceed the movable ranges of welding robots 10a, 10b, respectively, and the distributed control change amount will be inappropriate. If the distributed control change amount is inappropriate, influence amount evaluation unit 68 may reevaluate other distributed control change amounts (X1, X2, X3), or may temporarily stop welding robots 10a, 10b and positioner 20 if no appropriate solution is available. In this embodiment, the influence amount evaluation unit 68 evaluates the movement amount of the welding torches 13a, 13b as an influence associated with the correction, making it possible to correct the control amount within a range that maintains the accuracy of the operation of the welding robot 10 and the shape of the stacked beads 102. The same applies to the case where the amount of movement of other parts such as joints of the welding robot 10 is evaluated.

[0051] In this embodiment, the movement amount X1·T1 is used as an example of a first influence amount of the first control change amount on the first forming device, and the management reference value L1 is used as an example of a first threshold. In this embodiment, the movement amount X2·T2 is used as an example of a second influence amount of the second control change amount on the second forming device, and the management reference value L2 is used as an example of a second threshold. In this embodiment, an influence amount evaluation unit 68 is provided as an example of a determination unit that determines whether the first influence amount is smaller than the first threshold and the second influence amount is smaller than the second threshold. In this embodiment, the movement amount X1·T1 is used as an example of the first influence amount, which is the movement amount of a predetermined portion of the first forming device. In this embodiment, the movement amount X2·T2 is used as an example of the second influence amount, which is the movement amount of a predetermined portion of the second forming device.

[0052] Next, an example will be described in which the distance between the tip of welding torch 13a, 13b and the singular point of welding robot 10a, 10b is evaluated. Based on control change amounts X1, X2 after correction amount distribution by correction amount distribution unit 67 and the positions S1, S2 of the singular points of welding robot 10a, 10b, the distances between the tip of welding torch 13a, 13b and the singular point of welding robot 10a, 10b are |X1-S1| and |X2-S2|, respectively. Influence amount evaluation unit 68 then compares these distances with control reference values ​​L1, L2, respectively. These control reference values ​​L1, L2 may be set arbitrarily depending on the performance and management conditions of welding robot 10a, 10b. If distance |X1-S1| is below control reference value L1 and distance |X2-S2| is below control reference value L2, the operation of welding robot 10a, 10b is completed within the range of motion even using the distributed control change amounts. Conversely, if distance |X1-S1| is equal to or greater than control reference value L1, or if distance |X2-S2| is equal to or greater than control reference value L2, using the distributed control change amounts will cause welding torches 13a, 13b to exceed the movable ranges of welding robots 10a, 10b, respectively, and the distributed control change amounts will be inappropriate. If the distributed control change amounts are inappropriate, influence amount evaluation unit 68 may reevaluate other distributed control change amounts (X1, X2, X3), or may temporarily stop welding robots 10a, 10b and positioner 20 if no appropriate solution is available. In this embodiment, the influence amount evaluation unit 68 evaluates the change in posture of the welding robots 10a, 10b as an influence associated with the correction, making it possible to correct the control amount within a range that maintains the accuracy of the operation of the welding robots 10a, 10b and the shape of the stacked beads 102. The same applies to the case where the distance between the singular point and other parts such as joints of the welding robot 10 is evaluated.

[0053] In this embodiment, the distance |X1-S1| is used as an example of a first influence amount of the first control change amount on the first forming device, and the management reference value L1 is used as an example of a first threshold. In this embodiment, the distance |X2-S2| is used as an example of a second influence amount of the second control change amount on the second forming device, and the management reference value L2 is used as an example of a second threshold. In this embodiment, an influence amount evaluation unit 68 is provided as an example of a determination unit that determines whether the first influence amount is smaller than the first threshold and the second influence amount is smaller than the second threshold. In this embodiment, the distance |X1-S1| is used as an example of the first influence quantity, which is the distance between a predetermined portion of the first forming device and the singular point. In this embodiment, the distance |X2-S2| is used as an example of the second influence quantity, which is the distance between a predetermined portion of the second forming device and the singular point.

[0054] Although not shown in FIG. 1 , for example, a slider may be provided to move welding robot 10a within a predetermined range. In this case, influence amount evaluation unit 68 may evaluate the influence of the distributed control change amount on welding robot 10a by taking into account the range within which welding robot 10a can move using the slider. For example, influence amount evaluation unit 68 may set a new reference value to be used in place of control reference value L1 based on control reference value L1 and the range within which welding robot 10a can move. In this case, the slider is an example of a moving device that moves the first forming device, and influence amount evaluation unit 68 is an example of a determination unit that determines the first threshold based on the range within which the moving device can move the first forming device. Although not shown in FIG. 1, the same applies to the case where a slider is provided to move the welding robot 10b within a predetermined range. In this embodiment, by taking into consideration the positions to which the sliders move the welding robots 10a and 10b, it is possible to ensure a wide range in which feedback control can be performed.

[0055] The control program correction unit 69 corrects the control program executed by the control program execution unit 63 based on the control change amount after the correction amount distribution unit 67 distributes the correction amount. Specifically, when the control change amount is determined by the evaluation by the influence amount evaluation unit 68, the control program correction unit 69 corrects the control program based on the determined control change amount. Note that the control program correction unit 69 may correct the control program in real time or between passes. As a result, the control program execution unit 63 executes the corrected control program, and the welding robots 10a, 10b and the positioner 20 operate based on the control change amount after the correction amount distribution.

[0056] In this embodiment, a control program correction unit 69 is provided as an example of a control unit that controls the first forming device, the second forming device, and the adjustment device using a first control change amount, a second control change amount, and a third control change amount to manufacture a molded object by forming a bead on a base material.

[0057] [Stacking Planning System Operation] FIG. 9 is a flowchart showing an example of the operation of the stacking planning device 30 in this embodiment.

[0058] In the lamination planning device 30, first, the CAD data acquisition unit 41 acquires three-dimensional CAD data from the CAD device 25 (step 301). Next, the CAD data dividing unit 42 divides the three-dimensional CAD data acquired in step 301 into a plurality of layers to generate layer shape data (step 302). Next, the stacking plan unit 43 generates a stacking plan from the layer shape data generated in step 302 (step 303). Next, the control program generation unit 44 generates a control program for controlling the welding robots 10a and 10b to form the layered object 100 by forming the beads 102 according to the layering plan generated in step 303 (step 304). Meanwhile, the planned value acquisition unit 45 acquires planned values ​​related to the beads 102 to be layered by the welding robots 10a and 10b from the layering plan generated in step 303 (step 305). Finally, the information output unit 46 outputs the control program generated in step 304 and the planned values ​​generated in step 305 to the recording medium 70 (step 306).

[0059] [Control device operation] In the control device 50, first, the information acquisition unit 61 acquires the control program and the planned values ​​from the recording medium 70, and stores the control program in the control program storage unit 62 and the planned values ​​in the planned value storage unit 64. Then, the control program execution unit 63 reads out the control program stored in the control program storage unit 62 and executes it. At this time, the control device 50 controls the welding robots 10a and 10b to form the bead 102, while executing a control program correction process for cooperative control of the welding robots 10a and 10b.

[0060] FIG. 10 is a flowchart showing the contents of such a control program correction process.

[0061] As shown in the figure, in the control device 50, first, the performance value acquiring unit 65 acquires the performance values ​​related to the beads 102 laid by the welding robots 10a and 10b (step 501).

[0062] Next, the correction amount acquisition unit 66 acquires the correction amount for the additive manufacturing conditions of the welding robots 10a and 10b by comparing the actual value acquired in step 501 with the planned value stored in the planned value storage unit 64 (step 502). For example, the correction amount acquisition unit 66 may acquire the correction amounts Δv1 and Δv2 of the welding speeds of the welding robots 10a and 10b. Alternatively, correction amount acquisition unit 66 may acquire correction amounts Δz1 and Δz2 for the heights of welding torches 13a and 13b.

[0063] Next, the correction amount distribution unit 67 distributes the correction amount acquired in step 502 to the welding robots 10a and 10b and the positioner 20 (step 503). For example, when correction amounts Δv1 and Δv2 for the welding speeds of welding robots 10a and 10b are acquired in step 502, correction amount distributor 67 determines control change amounts (X1, X2, X3) based on these correction amounts Δv1 and Δv2, where X1 is the welding speed of welding robot 10a after the correction amounts have been distributed, X2 is the welding speed of welding robot 10b after the correction amounts have been distributed, and X3 is the angular velocity of positioner 20 after the correction amounts have been distributed. Alternatively, when correction amounts Δz1 and Δz2 for the heights of welding torches 13a and 13b are acquired in step 502, correction amount distributor 67 determines control change amounts (X1, X2, X3) based on these correction amounts Δz1 and Δz2. Here, X1 is the height of welding torch 13a after the correction amount is distributed, X2 is the height of welding torch 13b after the correction amount is distributed, and X3 is the height of the stage of positioner 20 after the correction amount is distributed.

[0064] Next, the influence amount evaluation unit 68 evaluates the influence amount on the postures of the welding robots 10a, 10b of the control change amount to which the correction amount has been distributed in step 503. That is, the influence amount evaluation unit 68 determines whether or not this influence amount is smaller than the control reference value (step 504). For example, the influence amount evaluation unit 68 may determine whether the movement amount of a specified part of the welding robot 10a is below the control reference value L1 and whether the movement amount of a specified part of the welding robot 10b is below the control reference value L2. Alternatively, the influence quantity evaluation unit 68 determines whether the distance between a specified portion of the welding robot 10a and the singular point is below the control standard value L1 and whether the distance between a specified portion of the welding robot 10b and the singular point is below the control standard value L2.

[0065] As a result, if the influence amount is equal to or greater than the control reference value, the influence amount evaluation unit 68 returns the process to step 503. As a result, the correction amount distribution unit 67 again distributes the correction amount to the welding robots 10a, 10b and the positioner 20, thereby determining another post-distribution control change amount (step 503). On the other hand, if the influence amount is smaller than the control reference value, the control program correction unit 69 corrects the control program so that the welding robots 10a, 10b and the positioner 20 operate using the control change amount determined in step 503 (step 505).

[0066] [Advantages of this embodiment] In this embodiment, the correction amount required for feedback control is distributed between welding robots 10a, 10b and positioner 20. This makes it possible to reduce the amount of change in the posture of each of welding robots 10a, 10b. [Explanation of symbols]

[0067] 1...metal additive manufacturing system, 10a, 10b...welding robot, 13a, 13b...welding torch, 20...positioner, 25...CAD device, 30...lamination planning device, 41...CAD data acquisition unit, 42...CAD data division unit, 43...lamination planning unit, 44...control program generation unit, 45...planned value acquisition unit, 46...information output unit, 50...control device, 61...information acquisition unit, 62...control program storage unit, 63...control program execution unit, 64...planned value storage unit, 65...actual value acquisition unit, 66...correction amount acquisition unit, 67...correction amount distribution unit, 68...influence amount evaluation unit, 69...control program correction unit, 70...recording medium

Claims

1. a first forming device for forming a bead by melting and solidifying a filler material; a second forming device for forming a bead by melting and solidifying a filler metal; an adjustment device for adjusting the position or posture of the base material; a control device that controls the first forming device, the second forming device, and the adjusting device so as to manufacture a shaped object by forming a bead on the base material; Equipped with a control device that determines a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for the adjustment device based on a first correction amount for the forming conditions of the first forming device and a second correction amount for the forming conditions of the second forming device, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount.

2. an acquisition unit that acquires a first correction amount for the forming conditions of a first forming device that forms a bead by melting and solidifying a filler metal, and a second correction amount for the forming conditions of a second forming device that forms a bead by melting and solidifying a filler metal; a determination unit that determines, based on the first correction amount and the second correction amount, a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for an adjustment device that adjusts a position or posture of a base material, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount; a control unit that controls the first forming device, the second forming device, and the adjusting device using the first control change amount, the second control change amount, and the third control change amount so as to manufacture a shaped object by forming a bead on the base material; A manufacturing control device for a molded object, comprising:

3. The control device for manufacturing a molded object according to claim 2 , wherein the determination unit determines the first control change amount and the second control change amount based on a difference between the first correction amount and the second correction amount.

4. the first correction amount is a correction amount for a bead formation speed of the first forming device, The control device for manufacturing a shaped object according to claim 3 , wherein the second correction amount is a correction amount for a bead formation speed of the second formation device.

5. the first correction amount is a correction amount for the position of a torch of the first forming device; The control device for manufacturing a molded object according to claim 3 , wherein the second correction amount is a correction amount for the position of a torch of the second forming device.

6. 3. The control device for manufacturing a molded object according to claim 2, further comprising a determination unit that determines whether a first influence amount of the first control change amount on the first forming device is smaller than a first threshold value and a second influence amount of the second control change amount on the second forming device is smaller than a second threshold value.

7. the first influence amount is a movement amount of a predetermined portion of the first forming device, The control device for manufacturing a shaped object according to claim 6 , wherein the second influence amount is a movement amount of a predetermined portion of the second forming device.

8. the first influence amount is a distance between a predetermined portion of the first forming device and a singular point, The control device for manufacturing a shaped object according to claim 6 , wherein the second influence amount is a distance between a specific portion of the second forming device and a singular point.

9. The control device for manufacturing a molded object according to claim 6, wherein the determination unit determines the first threshold value based on a range within which a moving device that moves the first forming device can move the first forming device.

10. an acquiring step in which a computer acquires a first correction amount for forming conditions of a first forming device that forms a bead by melting and solidifying a filler metal, and a second correction amount for forming conditions of a second forming device that forms a bead by melting and solidifying a filler metal; a determining step in which a computer determines, based on the first correction amount and the second correction amount, a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for an adjustment device that adjusts the position or attitude of the base material, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount; a control step in which a computer controls the first forming device, the second forming device, and the adjusting device using the first control variable, the second control variable, and the third control variable so as to manufacture a model by forming a bead on the base material; A manufacturing control method for a shaped object, comprising:

11. On the computer, a function of acquiring a first correction amount of a forming condition of a first forming device that forms a bead by melting and solidifying a filler metal, and a second correction amount of a forming condition of a second forming device that forms a bead by melting and solidifying a filler metal; a function of determining, based on the first correction amount and the second correction amount, a first control change amount for the first forming device, a second control change amount for the second forming device, and a third control change amount for an adjustment device that adjusts the position or attitude of the base material, so that both the first control change amount and the second control change amount are smaller than the larger of the first correction amount and the second correction amount; a function of controlling the first forming device, the second forming device, and the adjusting device using the first control variable amount, the second control variable amount, and the third control variable amount so as to manufacture a shaped object by forming a bead on the base material; A program to achieve this.

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