JP7391709B2 - Modeled object manufacturing method, modeled object manufacturing device, and program - Google Patents

Description

The present invention provides a method for manufacturing a molded object, an apparatus for manufacturing a molded object, which manufactures a molded object including a laminate in which a plurality of beads formed by melting and solidifying filler metal using an arc are stacked on a base material. Regarding the program.

The welding hand of the welding robot is operated according to a preset welding procedure, the welding location is visualized with an imaging camera arranged on the robot hand of the welding robot in line with the welding torch, and this visualized image information is stored in advance. A welding control method and welding control in a welding robot, in which the amount of deviation from the standard image is calculated by comparing it with the standard image that is provided, and the welding start position of the welding torch is determined based on this amount of deviation, and welding is performed. The device is known (for example, see Patent Document 1).

Japanese Patent Application Publication No. 2008-168299

When manufacturing a model that includes a laminate made of multiple stacked beads made by melting and solidifying filler metal using an arc, if a configuration is adopted in which a photographing section is placed in line with the welding torch, It is not possible to take a front image of the laminate being modeled. Therefore, it is not possible to correct the position of the welding torch by comparing the front image of the laminate in the stacking plan with the front image of the laminate during modeling.

An object of the present invention is to provide a front image of a laminate in a laminate plan and a laminate during modeling when manufacturing a modeled object including a laminate made of a plurality of stacked beads formed by melting and solidifying filler metal using an arc. The purpose is to compare the front image of the body and correct the position of the welding torch.

Based on such an object, the present invention provides a method for manufacturing a shaped article including a laminate made of a plurality of stacked beads formed by melting and solidifying filler metal using an arc, the method comprising: a step of installing an imaging unit at a position where a front image of the laminate can be photographed; a step of creating a planned image including a planned front image of the laminate from a stacking plan for stacking the laminate; and a step of photographing. Welding torch Provided is a method for manufacturing a shaped object, including a step of correcting the position.

In the correction step, the position of the welding torch may be corrected in the horizontal direction. In that case, the correction process includes a first correction in which the position of the welding torch is corrected in the horizontal direction without taking into account the bending of the filler metal protruding from the welding torch, and a first correction in which the position of the welding torch is corrected in the horizontal direction without considering the bending of the filler metal that protrudes from the welding torch. A second correction may be performed to correct the position of in the horizontal direction. The planned image includes the arc target position of the welding torch, the captured image includes an image of the welding torch, and the first correction is performed by adjusting the arc target position included in the planned image and the welding torch image included in the captured image. The correction may be based on the direction and amount of deviation from the position. The planning image includes a front image of the planned bead, the photographed image includes a front image of the bead being modeled, and the first correction is based on the position of the front image of the planned bead included in the planning image; The correction may be based on the direction and amount of deviation from the position of the front image of the bead being modeled included in the photographed image. The photographed image may include an image of the filler material, and the second correction may be a correction based on the direction and amount of bending of the image of the filler material included in the photographed image.

In the correction step, the position of the welding torch may be corrected in the vertical direction. In that case, the planning image includes a front image of the planned bead, the photographed image includes a front image of the bead being formed, and in the correction step, the position of the front image of the planned bead included in the planning image is The position of the welding torch may be corrected in the vertical direction based on the direction and amount of deviation from the position of the front image of the bead being modeled included in the photographed image.

In the correction step, the inclination of the welding torch may be corrected. In that case, the planning image includes a front image of the planned bead, the photographed image includes a front image of the bead being formed, and in the correction step, the front images of the planned bead included in the planning image are stacked. The inclination of the welding torch may be corrected based on the direction and amount of deviation between the direction and the stacking direction of the front image of the bead being modeled included in the photographed image.

The manufacturing method for the model is to rotate the welding torch around its own axis and use the imaging unit to photograph the filler metal protruding from the welding torch, detect the bending direction of the filler metal, and then detect the bending direction of the filler metal based on the bending direction. The method may further include the step of changing the attitude of the welding torch.

The present invention also provides a method for manufacturing a shaped article including a laminate formed by stacking a plurality of beads formed by melting and solidifying filler metal using an arc, the method being a method for manufacturing a shaped article including a laminate made from a stacking plan for laminating the laminate. A step of acquiring a planning image, which is an image that includes a front image of the planned laminate, and an image taken in the imaging department, which is an image of the laminate being modeled using a welding torch. Modeling including the step of acquiring a photographed image that is an image including a front image, and the step of correcting the position of a welding torch based on a comparison between the front image included in the planned image and the front image included in the photographed image. It also provides a method for manufacturing the product.

Furthermore, the present invention provides an apparatus for producing a shaped article including a laminate formed by stacking a plurality of beads formed by melting and solidifying a filler metal using an arc, which is created from a laminate plan for laminating the laminate. a planning image acquisition unit that acquires a planning image that is an image that includes a front image of the planned laminate; and an image that is taken in a photography department and that is an image that is an image that is an image that is an image that includes a front image of the planned laminate; A photographed image acquisition means that acquires a photographed image that includes a front image of the laminate, and corrects the position of the welding torch based on a comparison between the front image included in the plan image and the front image included in the photographed image. The present invention also provides an apparatus for manufacturing a shaped object, which includes a position correction means.

Furthermore, the present invention provides a program for causing a computer to function as an apparatus for manufacturing a shaped article including a laminate formed by stacking a plurality of beads formed by melting and solidifying filler metal using an arc. , a plan image acquisition means for acquiring a plan image, which is an image created from a stacking plan for stacking the laminate and including a front image of the planned laminate; A photographed image acquisition means for acquiring a photographed image, which is an image including a front image of a laminate being formed using a welding torch, a front image included in the planning image, and a front image included in the photographed image. We also provide a program for functioning as a position correction means for correcting the position of the welding torch based on the comparison with the above.

According to the present invention, when manufacturing a modeled object including a laminate in which a plurality of beads formed by melting and solidifying filler metal using an arc are stacked, a front image of the laminate in a laminate plan and a laminate during modeling are used. The position of the welding torch can be corrected by comparing the front image of the body.

1 is a diagram showing a schematic configuration example of a metal additive manufacturing system according to an embodiment of the present invention. 1 is a diagram showing an example of a hardware configuration of a control device in an embodiment of the present invention. It is a figure showing an example of a plan image created from a layered plan. It is a diagram showing an example of a photographed image photographed by a camera. FIG. 6 is a diagram showing a state when a planned image and a photographed image are superimposed and compared. FIG. 7 is a diagram showing another state when a planned image and a photographed image are superimposed and compared. (a) to (d) are diagrams showing examples of images taken with a camera while rotating a welding torch. 1 is a diagram showing an example of the functional configuration of a stack planning device in an embodiment of the present invention. 1 is a diagram showing an example of a functional configuration of a control device according to an embodiment of the present invention. It is a flow chart showing an example of the operation of the stacking planning device in the embodiment of the present invention. 7 is a flowchart showing an example of the operation of the torch position correction section of the control device according to the embodiment of the present invention. 7 is a flowchart showing an example of the operation of the torch posture correction section of the control device according to the embodiment of the present invention.

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

[Configuration of metal additive manufacturing system]
FIG. 1 is a diagram showing a schematic configuration example of a metal additive manufacturing system 1 in this embodiment.

As illustrated, the metal additive manufacturing system 1 includes a welding robot (manipulator) 10, a camera 15, a CAD device 20, a layer planning device 30, and a control device 50. Further, the stack planning device 30 writes a control program for controlling the welding robot 10 in a removable recording medium 70 such as a memory card, and the control device 50 can read the control program written in the recording medium 70. It looks like this.

The welding robot 10 includes an arm 11 having a plurality of joints, and performs welding work by operating according to a control program read by a control device 50. The welding robot 10 also has a welding torch 13 at the tip of the arm 11 via the wrist 12 for modeling a layered product 100, which is an example of a layered product. In the case of the metal additive manufacturing system 1, the welding robot 10 moves the welding torch 13 while melting the filler material (wire) 14 made of mild steel to manufacture the additively manufactured article 100. Specifically, while supplying the filler metal 14, the welding torch 13 generates an arc while flowing the shield gas to melt and solidify the filler metal 14, thereby forming multiple layers of beads 101 on the base metal 90. A laminate-molded article 100 is manufactured by laminating the layers. Although an arc is used here as a heat source for melting the filler metal 14, a laser or plasma may also be used. In addition, the welding robot 10 also includes a feeding device that feeds the filler metal 14, but a description of this will be omitted.

The camera 15 is fixed at a position where it can take a front image of the layered object 100 being formed using the welding torch 13 . This position is a position set with reference to the base material 90. For example, the camera 15 captures a front image of the laminate-molded article 100 before or after the formation of one pass of the bead 101 starts or ends. Here, the term "front image" refers to an image viewed from the direction in which the beads are stretched. In this embodiment, a camera 15 is provided as an example of a photographing section.

The CAD device 20 has a function of designing a molded object using a computer and retaining three-dimensional data (hereinafter referred to as "three-dimensional CAD data") obtained by the design.

The layer planning device 30 creates a layer plan for the layered object 100 based on three-dimensional CAD data held by the CAD device 20. That is, the trajectory of the welding torch 13 is determined, and the welding conditions when the welding robot 10 performs welding are determined. Then, a control program for controlling the welding robot 10 to form the bead 101 under the determined welding conditions along the determined trajectory is generated, and this control program is output to the recording medium 70.

The control device 50 reads a control program from the recording medium 70 and holds it. By operating this control program, beads are welded under the welding conditions determined by the stack planning device 30 according to the stack plan created by the stack planning device 30, that is, along the trajectory determined by the stack planning device 30. The welding robot 10 is controlled to form the welding robot 101. In this embodiment, a control device 50 is provided as an example of a device for manufacturing a shaped object.

[Hardware configuration of control device]
FIG. 2 is a diagram showing an example of the hardware configuration of the control device 50.

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 calculation means, a main memory 52 as a storage means, and a magnetic disk device (HDD: Hard Disk Drive) 53. Equipped with 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 their execution, and the HDD 53 is a storage area that stores input data for various programs, output data from the various programs, and the like.

The control device 50 also has a communication I/F 54 for communicating with the outside, a display mechanism 55 consisting of a video memory, a display, etc., an input device 56 such as a keyboard and a mouse, and a storage medium 70 for data transmission. A driver 57 for reading and writing is provided. Note that FIG. 2 merely illustrates the hardware configuration when the control device 50 is implemented as a computer system, and the control device 50 is not limited to the illustrated configuration.

Further, the hardware configuration shown in FIG. 2 can also be regarded as the hardware configuration of the stack 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. The disk device 33, the communication I/F 34, the display mechanism 35, the input device 36, and the driver 37 will be expressed.

[Overview of this embodiment]
First, in this embodiment, the metal additive manufacturing system 1 corrects the position of the welding torch 13 based on a comparison between the image obtained from the layer plan and the image obtained from the camera 15.

Specifically, the following general operations are performed.

That is, first, the metal additive manufacturing system 1 creates a layered product that would be obtained if layering was performed according to the layering plan based on the layering plan created by the layering planning device 30 in accordance with the magnification and viewing angle of the camera 15. A front image (hereinafter referred to as "planned image IP") of the layered object 100 is created. Note that the plan image IP also includes the arc target position.

FIG. 3 is a diagram showing an example of this plan image IP. Here, a case is taken as an example where the trajectory of the welding torch 13 in the lamination plan exists in three layers with three passes per layer in a direction perpendicular to the lens surface of the camera 15. That is, if the j-th bead from the left of the i-th layer from the bottom in the image is B (i, j), then the planned image IP shows bead B (1, 1) from the left on the image of the base material 90. The front images of ~B(1,3) are lined up, on top of which the front images of beads B(2,1) to B(2,3) are lined up from the left, and then the front images of beads B(3,1) are lined up from the left. ) to B(3,3) are lined up. Further, the arc target position corresponding to bead B(i,j) is shown as P(i,j).

Next, the metal additive manufacturing system 1 acquires a front image (hereinafter referred to as "photographed image IC") of the actual additively manufactured product 100 by photographing the additively manufactured product 100 during additive manufacturing with the camera 15. . At this time, the welding torch 13 uses the wire feeding function to feed the filler metal (wire) 14 until it comes into contact with the surface of the bead.

FIG. 4 is a diagram showing an example of this photographed image IC. Here, in the case where the trajectory of the welding torch 13 in the stacking plan is 3 passes per layer in the direction perpendicular to the lens surface of the camera 15 as described above, and there are 3 layers, the state where up to the first layer is stacked is an example. I'm keeping it. That is, if the j-th bead from the left of the i-th layer from the bottom in the image is B (i, j), the photographed image IC shows bead B (1, 1) from the left on the image of the base material 90. The front images of ~B(1,3) are lined up. Further, the photographed image IC includes an image of the welding torch 13 positioned to form the bead B (2, 1) on the bead B (1, 1) and the filler material sent out from the welding torch 13. It further includes 14 images.

After that, the metal additive manufacturing system 1 superimposes and compares the planning image IP and the photographed image IC.

FIG. 5-1 is a diagram showing a state when the planning image IP and the photographed image IC are superimposed and compared. In the figure, the base material 90, beads B(1,1) to B(1,3), welding torch 13, and filler metal 14 in the photographed image IC are shown by solid lines. On the other hand, the base material 90, beads B(1,1) to B(3,3), and arc target positions P(1,1) to P(3,3) in the planning image IP are indicated by broken lines. However, regarding the base material 90 and beads B(1,1) to B(1,3), the plan image IP and photographed image IC completely overlap, so the broken lines cannot be distinguished.

By superimposing and comparing the planning image IP and the captured image IC in this way, the metal additive manufacturing system 1 determines the direction of deviation between the arc target position in the planning image IP and the tip position of the filler metal 14 in the captured image IC. and calculate the amount of deviation. In this case, the direction of deviation is either the direction D1 or the direction D3 set according to the camera 15 in FIG. 5A.

Specifically, the metal additive manufacturing system 1 calculates the direction and amount of deviation between the arc target position in the planning image IP and the position of the welding torch 13 in the captured image IC. Alternatively, the direction and amount of deviation in the horizontal direction between the position of the bead front image in the plan image IP and the position of the bead front image in the photographed image IC may be calculated.

However, if this is only the case, and the tip of the filler metal 14 is bent, the calculated deviation direction and amount will be the deviation between the arc target position in the planned image IP and the tip position of the filler metal 14 in the photographed image IC. The direction and amount of deviation do not match. Therefore, the metal additive manufacturing system 1 detects the bending direction and bending amount of the tip of the image of the filler material 14 from the photographed image IC. Then, by adding or subtracting the bending direction and amount of the tip of the image of the filler metal 14 from the direction and amount of deviation between the arc aim position and the position of the welding torch 13, the arc aim position and the filler metal The direction and amount of deviation from the tip position of No. 14 are calculated.

For example, in FIG. 5-1, it is assumed that the welding torch 13 is shifted by α in the direction D1 from the arc target position P (2, 1), and the tip of the filler metal 14 is bent by β in the direction D1. Then, the tip position of the filler metal 14 is shifted by (α+β) in the direction D1 from the arc target position P(2,1).

Thereafter, the metal additive manufacturing system 1 corrects the position of the welding torch 13 based on the shift direction and shift amount determined above. That is, the relative position of welding torch 13 with respect to camera 15 is corrected. For example, as mentioned above, if the tip position of the filler metal 14 is shifted by (α+β) in the direction D1 from the arc target position P(2,1), then the welding torch 13 is moved by (α+β) in the direction D3. let

Note that, in the above description, the planned image IP includes both the planned front image of the bead 101 and the arc target position of the welding torch 13, but this is not the case. The planning image IP may include only the minimum necessary elements for correcting the horizontal position of the welding torch 13. Specifically, the planning image IP includes the arc aiming position only when correction is performed based on the direction and amount of deviation between the arc aiming position in the planning image IP and the position of the welding torch 13 in the captured image IC. do it. In addition, only when correction is performed based on the direction and amount of deviation in the horizontal direction between the position of the bead front image in the planning image IP and the position of the bead front image in the photographed image IC, the planning image IP is It suffices to include a front image of the front image.

In addition, by superimposing and comparing the planning image IP and the photographed image IC, the metal additive manufacturing system 1 can determine the position of the welding torch 13 in the photographed image IC and the appropriate position of the welding torch 13 determined from the bead front image. The direction and amount of deviation may be calculated. In this case, the direction of deviation is either the direction D2 or the direction D4 set according to the camera 15 in FIG. 5A.

Specifically, for the bead 101 one layer before, the direction and amount of deviation between the upper surface of the bead front image in the planning image IP and the upper surface of the bead front image in the photographed image IC are calculated. Then, by adding or subtracting the calculated amount of deviation from the distance predetermined as an appropriate distance between the upper surface of the bead 101 of the previous layer and the welding torch 13 according to the direction of deviation, the actual welding torch is 13 and the appropriate position of the welding torch 13 are calculated.

For example, in FIG. 5-1, assume that the top surface of bead B (1, 1) in photographed image IC is shifted by γ in direction D2 from the top surface of bead B (1, 1) in planning image IP. In other words, assume that bead B (1, 1) is lower than planned by γ. Then, the actual position of the welding torch 13 is shifted by γ in the direction D2 from the appropriate position of the welding torch 13 determined from the upper surface of the bead B (1, 1).

Thereafter, the metal additive manufacturing system 1 corrects the position of the welding torch 13 based on the shift direction and shift amount determined above. That is, the relative position of welding torch 13 with respect to camera 15 is corrected. For example, as described above, if the actual position of the welding torch 13 is shifted by γ in the direction D4 from the appropriate position of the welding torch 13 determined from the top surface of the bead B (1, 1), then the welding torch 13 is Move D2 by γ.

FIG. 5-2 is a diagram showing another state when the planning image IP and the photographed image IC are superimposed and compared.

In the figure, the plan image IP is indicated by a broken line. The plan image IP takes as an example a case where the trajectory of the welding torch 13 in the lamination plan exists in six layers with one pass per layer in a direction perpendicular to the lens surface of the camera 15. That is, assuming that the bead in the i-th layer from the bottom in the image is B(i), the planned image IP includes front images of beads B(1) to B(6) from the bottom on the image of the base material 90. They are lined up. Further, the arc target position corresponding to bead B(i) is shown as P(i). Therefore, the base material 90, beads B(1) to B(6), and arc target positions P(1) to P(6) are indicated by broken lines. However, since the base material 90 and some of the beads B(1) to B(3) completely overlap in the planned image IP and photographed image IC, the broken lines cannot be distinguished.

Further, the photographed image IC is shown by a solid line. The photographed image IC shows a state where up to the third layer is laminated when the trajectory of the welding torch 13 in the lamination plan exists in the direction perpendicular to the lens surface of the camera 15 as described above, with one pass per layer and six layers. is taken as an example. That is, if the bead of the i-th layer from the bottom in the image is B'(i), the photographed image IC shows beads B'(1) to B'(3) from the bottom on the image of the base material 90. The front images are lined up. The captured image IC also includes an image of the welding torch 13 positioned to form bead B'(4) on bead B'(3), and an image of the filler metal 14 sent out from the welding torch 13. It also includes images. Therefore, the base material 90, beads B'(1) to B'(3), welding torch 13, and filler metal 14 are shown as solid lines.

By superimposing and comparing the planning image IP and the captured image IC in this way, the metal additive manufacturing system 1 can determine the stacking direction of the bead front image in the planning image IP and the stacking direction of the bead front image in the captured image IC. Calculate the direction and amount of deviation. In this case, the direction of deviation is either clockwise or counterclockwise.

Specifically, the direction that connects the centers of the bead front images stacked in the planning image IP or the arc target positions is the stacking direction in the planning image IP, and the direction that connects the centers of the stacked bead front images in the photographed image IC. is the stacking direction in the photographed image IC. Then, the direction and amount of deviation between the stacking direction in the plan image IP and the stacking direction in the captured image IC, that is, the angle formed by these directions, are calculated.

For example, as shown in FIG. 5-2, assume that the stacking direction of the bead front images in the photographed image IC is tilted counterclockwise by θ from the stacking direction of the bead front images in the planning image IP. Then, the direction of inclination of the welding torch 13 is deviated from the planned direction by θ in the counterclockwise direction.

Thereafter, the metal additive manufacturing system 1 corrects the inclination of the welding torch 13 based on the shift direction and shift amount determined above. That is, the relative position of welding torch 13 with respect to camera 15 is corrected. For example, as described above, if the inclination direction of the welding torch 13 is deviated by θ in the counterclockwise direction from the planned stacking direction, the welding torch 13 is tilted on a plane parallel to the lens surface of the camera 15. Rotate clockwise by θ.

Second, in this embodiment, the metal additive manufacturing system 1 photographs the filler metal 14 with the camera 15 while rotating the welding torch 13 about its own axis, and evaluates the bending direction of the filler metal 14. Then, the posture of the welding torch 13 is corrected.

FIGS. 6A to 6D are diagrams showing examples of photographed images IC taken by the camera 15 while rotating the welding torch 13.

(a) is a photographed image IC with the welding torch 13 not rotating. In this photographed image IC, the tip of the filler material 14 is bent in the direction D1.

(b) is a photographed image IC in which the welding torch 13 in the state of (a) is rotated 90° counterclockwise when viewed from above, for example. In this photographed image IC, the tip of the filler metal 14 is perpendicular to the lens surface of the camera 15 and bent in a direction away from the camera 15, so the bending of the filler metal 14 cannot be confirmed.

(c) is a photographed image IC in which the welding torch 13 in the state of (b) is further rotated by 90° counterclockwise when viewed from the top, for example. In this photographed image IC, the tip of the filler material 14 is bent in the direction D3.

(d) is a photographed image IC in which the welding torch 13 in the state of (b) is further rotated by 90° counterclockwise when viewed from the top, for example. In this photographed image IC, the tip of the filler metal 14 is perpendicular to the lens surface of the camera 15 and bent in a direction approaching the camera 15, so the bending of the filler metal 14 cannot be confirmed.

In this case, the metal additive manufacturing system 1 performs welding with the welding torch 13 in the state (b) or (d).

[Functional configuration of this embodiment]
(Functional configuration of layer planning device)
FIG. 7 is a diagram showing an example of the functional configuration of the stacking planning device 30 in this embodiment. As illustrated, the stack planning device 30 in this embodiment includes a CAD data acquisition section 41, a CAD data division section 42, a stack planning section 43, a control program generation section 44, a plan image generation section 45, and an information output section 46.

The CAD data acquisition unit 41 acquires three-dimensional CAD data representing the three-dimensional shape of the layered object 100 from the CAD device 20 .

The CAD data division unit 42 divides (slices) the three-dimensional CAD data acquired by the CAD data acquisition unit 41 into a plurality of layers, thereby generating a plurality of layer shape data each representing the shape of each layer. At this time, the CAD data dividing unit 42 may convert the three-dimensional CAD data into an internal format that can be easily divided into a plurality of layers.

The stacking planning unit 43 generates a stacking plan including welding conditions and arc target positions when welding the bead 101 that matches the height and width of each layer of the plurality of layer shape data generated by the CAD data dividing unit 42. To generate such a stacking plan, a model that approximates the height and width of the bead 101 as well as the cross-sectional shape of the bead 101 is required. These may be actual values from measurement experiments or estimated values calculated from the cross-sectional area of the amount of welded metal. In this embodiment, bead-on-plate welding and vertical stacking of several layers are performed while varying the welding speed and wire feed speed under several conditions to change the amount of welding, and the height and width of each layer are determined under each condition. Create a database of measurement results. Then, when stacking, the welding speed and amount of welding that satisfy the desired height and width of the stack are selected, the estimated shape of each layer is calculated from the measurement results as needed, and the arc target position is determined. Note that the calculation method for calculating the welded cross section may be changed depending on the material of the filler metal 14 and the state of the shape of the already laminated parts. Using this calculation method, we plan the lamination that will contain the object.

The control program generation unit 44 generates a control program for controlling the welding robot 10 to perform welding according to the stacking plan generated by the stacking planning unit 43.

The plan image generating section 45 generates a plan image IP from the stack plan generated by the stack planning section 43. For example, the stacking plan is based on a row of the cross-sectional shape of the bead 101 and the arc target position for each layer of the plurality of layer shape data generated by the CAD data dividing unit 42, as a row of three-dimensional coordinates with the base material 90 as a reference. include. Therefore, by fixing the camera 15 at a predetermined position with respect to the base material 90, it is possible to calculate the cross-sectional shape of the bead 101 and the three-dimensional coordinate sequence of the arc target position with respect to the camera 15. . Since the coordinates of the intersection of this three-dimensional coordinate array with an arbitrary plane parallel to the lens surface of the camera 15 are also known, the cross-sectional shape of the bead 101 on that plane and the arc target position are also known. However, the range of the photographed image IC is obtained by reducing the photographing range on the plane according to the magnification and viewing angle of the camera 15. Therefore, by enlarging the length on the photographed image IC based on the magnification and viewing angle of the camera 15, the distance from the camera 15 to the plane, etc., the actual length on the plane is calculated. .

The information output unit 46 outputs information including the control program generated by the control program generation unit 44 and the plan image IP generated by the plan image generation unit 45 to the recording medium 70.

(Functional configuration of control device)
FIG. 8 is a diagram showing an example of the functional configuration of the control device 50 in this embodiment. As illustrated, the control device 50 in this embodiment includes an information acquisition section 61, a control program storage section 62, a control program execution section 63, a planned image storage section 64, a captured image reception section 65, and a torch. It includes a position correction section 66 and a torch posture correction section 67.

The information acquisition unit 61 acquires information recorded on the recording medium 70. This information includes a control program and a planning image IP. In the present embodiment, as an example of a plan image acquisition means for acquiring a plan image that is an image created from a stacking plan for stacking stacked bodies and includes a front image of the planned stacked body, the information An acquisition section 61 is provided.

The control program storage unit 62 stores a control program 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. Thereby, the control program execution unit 63 controls the welding robot 10 to form the bead 101 according to the stacking plan generated by the stacking planning unit 43. Further, the control program execution unit 63 calls the torch position correction unit 66 to correct the position of the welding torch 13, for example, after one pass of welding is completed. Further, the control program execution unit 63 calls the torch attitude correction unit 67 to correct the attitude of the welding torch 13, for example, before starting one pass of welding.

The plan image storage unit 64 stores the plan image IP among the information acquired by the information acquisition unit 61.

The photographed image receiving section 65 controls the camera 15 according to instructions from the torch position correcting section 66 or the torch posture correcting section 67 to take a front image of the layered object 100 being formed. Then, the photographed image IC, which is the photographed front image, is received from the camera 15. In this embodiment, as an example of a photographed image acquisition unit that acquires a photographed image that is an image photographed in a photographing section and includes a front image of a laminate that is being modeled using a welding torch, the photographed image A receiving section 65 is provided.

When called by the control program execution unit 63, the torch position correction unit 66 controls the captured image receiving unit 65 to receive the captured image IC from the camera 15, and acquires the captured image IC. Then, the torch position correction unit 66 compares the planned image IP stored in the planned image storage unit 64 with the photographed image IC acquired from the photographed image receiving unit 65, and determines the direction and amount of displacement of the position of the welding torch 13. Detect. Then, the position of the welding torch 13 is corrected based on the detected direction and amount of deviation.

Here, as described above, the correction of the position of the welding torch 13 includes correction of the position of the welding torch 13 in the horizontal direction, correction of the position of the welding torch 13 in the vertical direction, and correction of the inclination of the welding torch 13. be.

First, a case will be described in which the position of the welding torch 13 is corrected in the horizontal direction. In this case, the torch position correction unit 66 first detects the direction and amount of deviation between the arc target position in the planning image IP and the position of the welding torch 13 in the photographed image IC, and based on the direction and amount of deviation, The position of the welding torch 13 is corrected in the horizontal direction. Alternatively, the direction and amount of deviation in the horizontal direction between the position of the bead front image in the plan image IP and the position of the bead front image in the captured image IC are detected, and the position of the welding torch 13 is determined based on the direction and amount of deviation. Correct horizontally. The correction based on the direction and amount of deviation is an example of a first correction in which the position of the welding torch is corrected in the horizontal direction without considering the bending of the filler metal. Thereafter, the bending direction and bending amount of the filler metal 14 in the photographed image IC are detected, and the position of the welding torch 13 is further corrected in the horizontal direction based on the bending direction and bending amount. This correction based on the bending direction and bending amount is an example of a second correction in which the position of the welding torch is corrected in the horizontal direction in consideration of the bending of the filler metal.

Next, a case will be described in which the position of the welding torch 13 is corrected in the vertical direction. In this case, the torch position correction unit 66 detects the direction and amount of deviation in the vertical direction between the position of the bead front image in the planning image IP and the position of the bead front image in the photographed image IC, and detects the direction and amount of deviation in the vertical direction. The position of the welding torch 13 is corrected in the vertical direction based on.

Next, a case of correcting the inclination of the welding torch 13 will be described. In this case, the torch position correction unit 66 adjusts the slope of the line connecting the centers of the stacked bead front images or the arc target positions in the planning image IP, and the line connecting the centers of the stacked bead front images in the captured image IC. The direction and amount of deviation from the inclination of the welding torch 13 are detected, and the inclination of the welding torch 13 is corrected based on the direction and amount of deviation.

In this embodiment, a torch position correction unit 66 is provided as an example of a position correction unit that corrects the position of the welding torch based on a comparison between the front image included in the plan image and the front image included in the photographed image. .

When called by the control program execution unit 63, the torch posture correction unit 67 controls the welding robot 10 to rotate the welding torch 13, and also controls the captured image receiving unit 65 to receive a captured image IC from the camera 15 for each rotation. is controlled to obtain a captured image IC for each rotation. Then, the welding robot 10 is controlled to perform welding by specifying the rotation with the smallest bend on the photographed image IC, and by rotating the welding torch 13 by the angle of that rotation.

[Operation of this embodiment]
(Operation of layer planning device)
FIG. 9 is a flowchart showing an example of the operation of the stacking planning device 30 in this embodiment.

In the stack planning device 30, first, the CAD data acquisition unit 41 acquires three-dimensional CAD data from the CAD device 20 (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 stack planning unit 43 generates a stack plan from the layer shape data generated in step 302 (step 303).

Next, the control program generation unit 44 generates a control program that controls the welding robot 10 to model the additively manufactured article 100 by forming the bead 101 according to the lamination plan generated in step 303 (step 304). .

On the other hand, the plan image generation unit 45 generates a plan image IP, which is a front image of the layered object 100 being modeled, from the layer plan generated in step 303 (step 305).

Finally, the information output unit 46 outputs the control program generated in step 304 and the plan image IP generated in step 305 to the recording medium 70 (step 306).

(Operation of control device)
In the control device 50, the information acquisition unit 61 first acquires the control program and the planned image IP from the recording medium 70, and stores the control program in the control program storage unit 62 and the planned image IP in the planned image storage unit 64, respectively. do. Then, the control program execution section 63 reads out the control program stored in the control program storage section 62 and executes it.

At this time, the control program executed by the control program execution section 63 calls and executes the torch position correction section 66 every time one pass of welding is completed, for example.

FIG. 10 is a flowchart showing an example of the operation of the torch position correction section 66. In addition, in this flowchart, when correcting the position of the welding torch 13 in the horizontal direction, in particular, after correcting the deviation between the arc aiming position and the position of the welding torch 13, The case where the correction amount is adjusted will be explained.

As shown in the figure, when called from the control program, the torch position correction unit 66 first controls the captured image receiving unit 65 to cause the camera 15 to capture a captured image IC and receive it, and A captured image IC is acquired from 65 (step 501).

Thereby, the torch position correction unit 66 compares the arc aiming position in the plan image IP stored in the plan image storage unit 64 with the position of the welding torch 13 in the captured image IC acquired in step 501, and The direction and amount of displacement are detected (step 502).

Then, the torch position correction unit 66 corrects the position of the welding torch 13 based on the direction and amount of deviation of the welding torch 13 detected in step 502 (step 503). That is, the welding robot 10 is controlled to shift the welding torch 13 by the amount of shift in the direction opposite to the direction of shift.

Thereafter, the torch position correction unit 66 detects the bending direction and bending amount of the filler material 14 in the captured image IC acquired in step 501 (step 504).

Then, the torch position correction unit 66 corrects the position of the welding torch 13 based on the bending direction and bending amount of the filler metal 14 detected in step 504 (step 505). That is, the welding robot 10 is controlled to shift the welding torch 13 in the opposite direction to the bending direction by the bending amount.

Further, in addition to this, the control program executed by the control program execution section 63 may call the torch posture correction section 67 and execute it, for example, before starting one pass of welding.

FIG. 11 is a flowchart showing an example of the operation of the torch posture correction section 67. In this flowchart, it is assumed that the welding torch 13 is rotated by 360° by rotating (360/n)° n times (n is a natural number). The examples shown in FIGS. 6(a) to 6(d) are examples where n=4.

As shown in the figure, when called from the control program, the torch posture correction unit 67 first sets an index i indicating the number of rotations of the welding torch 13 to 1 (step 551). Then, the following process is performed while increasing the index i by 1 until the index i exceeds n.

That is, the torch posture correction unit 67 controls the welding robot 10 to rotate the welding torch 13 by (i×360/n)° (step 552). Next, the photographed image receiving section 65 is controlled to cause the camera 15 to photograph and receive the photographed image IC, and the photographed image IC is acquired from the photographed image receiving section 65 (step 553). Then, 1 is added to index i (step 554).

Thereafter, the torch posture correction unit 67 determines whether the index i exceeds n (step 555). If the torch attitude correction unit 67 determines that the index i does not exceed n, the process returns to step 552, and if it determines that the index i exceeds n, the process proceeds to step 556.

Next, the torch posture correction unit 67 calculates an index k when the bending of the filler material 14 is minimized from the captured image IC acquired in step 553 while increasing the index i from 1 to n, and The rotation angle of the welding torch 13 that minimizes the bending is determined as (k×360/n)° (step 556).

Thereby, the torch posture correction unit 67 controls the welding robot 10 to rotate the welding torch 13 by the rotation angle determined in step 556 (step 557).

[Effects of this embodiment]
As described above, in this embodiment, the plan image IP including the front image of the laminate-produced object 100 created from the laminate plan and the front image of the laminate-produced object 100 that is being modeled taken by the camera 15 are used. The position of the welding torch 13 is corrected based on a comparison between the front image included in the planning image IP and the front image included in the captured image IC. As a result, when manufacturing a layered object 100 by stacking a plurality of beads 101 formed by melting and solidifying the filler material 14 using an arc, the front image of the layered object 100 in the layering plan and the layered object being formed It has become possible to correct the position of the welding torch 13 by comparing the front image of the object 100.

DESCRIPTION OF SYMBOLS 1... Metal additive manufacturing system, 10... Welding robot, 20... CAD device, 30... Lamination planning device, 41... CAD data acquisition part, 42... CAD data division part, 43... Lamination planning part, 44... Control program generation part, 45... Planned image generation section, 46... Information output section, 50... Control device, 61... Information acquisition section, 62... Control program storage section, 63... Control program execution section, 64... Planned image storage section, 65... Captured image reception Part, 66...Torch position correction part, 67...Torch posture correction part, 70...Recording medium

Claims (14)

A method for manufacturing a shaped article including a laminate made of a plurality of stacked beads formed by melting and solidifying filler metal using an arc,
a step of installing a photographing unit at a position where a front image of the laminate being modeled can be photographed using a welding torch;
a step of creating a plan image including a front image of the planned laminate from a stacking plan for stacking the laminate;
acquiring a photographed image including a front image of the laminate being modeled taken in the photographing section;
A method for manufacturing a shaped object, comprising the step of correcting the position of the welding torch based on a comparison between a front image included in the plan image and a front image included in the photographed image. 2. The method of manufacturing a shaped article according to claim 1, wherein in the correcting step, the position of the welding torch is corrected in a horizontal direction. In the correction step, the first correction corrects the position of the welding torch in the horizontal direction without considering the bending of the filler metal protruding from the welding torch, and the first correction takes into account the bending of the filler metal. 3. The method of manufacturing a shaped article according to claim 2, further comprising performing a second correction of horizontally correcting the position of the welding torch. The plan image includes an arc target position of the welding torch,
The photographed image includes an image of the welding torch,
The first correction is a correction based on the direction and amount of deviation between the arc target position included in the plan image and the position of the welding torch image included in the photographed image. Item 3. The method for producing a shaped article according to item 3. the planning image includes a frontal image of the planned bead;
The photographed image includes a front image of the bead being formed,
The first correction is a correction based on the direction and amount of deviation between the position of the planned front image of the bead included in the planning image and the position of the front image of the bead being modeled included in the photographed image. The method for manufacturing a shaped article according to claim 3, characterized in that: The photographed image includes an image of the filler material,
4. The method for manufacturing a shaped object according to claim 3, wherein the second correction is a correction based on a bending direction and a bending amount of an image of the filler material included in the photographed image. 2. The method of manufacturing a shaped article according to claim 1, wherein in the correcting step, the position of the welding torch is corrected in a vertical direction. the planning image includes a frontal image of the planned bead;
The photographed image includes a front image of the bead being formed,
In the correcting step, the correction is performed based on the direction and amount of deviation between the position of the planned front image of the bead included in the planning image and the position of the front image of the bead being modeled included in the photographed image. 8. The method for manufacturing a shaped article according to claim 7, wherein the position of the welding torch is corrected in the vertical direction. 2. The method of manufacturing a shaped article according to claim 1, wherein in the correcting step, the inclination of the welding torch is corrected. the planning image includes a frontal image of the planned bead;
The photographed image includes a front image of the bead being formed,
The correcting step is based on the direction and amount of deviation between the stacking direction of the front image of the planned bead included in the planning image and the stacking direction of the front image of the bead being modeled included in the photographed image. 10. The method of manufacturing a shaped article according to claim 9, further comprising correcting the inclination of the welding torch. While rotating the welding torch around its own axis, the photographing unit photographs the filler metal protruding from the welding torch, detects the bending direction of the filler metal, and performs the welding based on the bending direction. The method for manufacturing a shaped article according to claim 1, further comprising the step of changing the orientation of the torch. A method for manufacturing a shaped article including a laminate made of a plurality of stacked beads formed by melting and solidifying filler metal using an arc,
acquiring a plan image that is an image created from a stacking plan for stacking the laminate and includes a front image of the planned laminate;
a step of acquiring a photographed image, which is an image photographed in a photographing department and is an image including a front image of the laminate being modeled using a welding torch;
A method for manufacturing a shaped object, comprising the step of correcting the position of the welding torch based on a comparison between a front image included in the plan image and a front image included in the photographed image. An apparatus for manufacturing a shaped article including a laminate made of a plurality of stacked beads formed by melting and solidifying filler metal using an arc,
a plan image acquisition unit that acquires a plan image that is an image created from a stacking plan for stacking the laminate and includes a front image of the planned laminate;
a photographed image acquisition means for acquiring a photographed image that is an image photographed in a photographing section and includes a front image of the laminate being formed using a welding torch;
An apparatus for manufacturing a shaped object, comprising: a position correction means for correcting the position of the welding torch based on a comparison between a front image included in the plan image and a front image included in the photographed image. . A program for causing a computer to function as a manufacturing device for a shaped article including a laminate of a plurality of stacked beads formed by melting and solidifying filler metal using an arc, the program comprising:
The computer,
a plan image acquisition unit that acquires a plan image that is an image created from a stacking plan for stacking the laminate and includes a front image of the planned laminate;
a photographed image acquisition means for acquiring a photographed image that is an image photographed in a photographing section and includes a front image of the laminate being formed using a welding torch;
A program for functioning as a position correction means for correcting the position of the welding torch based on a comparison between a front image included in the plan image and a front image included in the photographed image.