JP7560416B2 - Method for controlling layered manufacturing device, layered manufacturing device, and program - Google Patents

Description

The present invention relates to a method for controlling an additive manufacturing device, an additive manufacturing device, and a program.

There is a known technology for forming three-dimensional structures by stacking weld beads made by melting and solidifying a filler metal (see Patent Document 1). Patent Document 1 describes a technology for preventing droplets of the filler metal from flowing off the weld surface due to the curvature of the surface when creating a model with a complex three-dimensional free-form surface while moving a welding torch, by making the weld surface directly below the welding torch approximately horizontal. Patent Document 1 states that this makes it possible to reliably form weld beads on the weld surface even for complex three-dimensional free-form shapes.

JP 2007-275945 A

As described above, when additive manufacturing is performed on a complex shape, the posture of the object relative to the welding torch during manufacturing is changed in various ways.
However, when manufacturing a model using a welding robot (manipulator) with a welding torch attached to the end of its arm, it is difficult to always fix the posture of the manipulator while manufacturing the model, since there are many variations in the lamination direction and order of the weld beads. One possible solution is to change the posture of the positioner that holds the model, but the larger the model, the more difficult it becomes to change the posture using the positioner. In addition, the operation of the end of the robot arm greatly affects the accuracy of the target position and the accuracy of linear movement, and unacceptable errors may occur depending on the posture of the manipulator.

The present invention aims to provide a control method, an additive manufacturing device, and a program for an additive manufacturing device that can form a weld bead in each stacking pass with the manipulator in an appropriate position, even when additive manufacturing an object using a manipulator with a welding torch attached to its tip, thereby improving manufacturing accuracy and productivity.

The present invention comprises the following configurations.
(1) A method for controlling an additive manufacturing device in which a welding torch that melts and solidifies a wire-shaped filler metal while generating an arc is moved by a manipulator held at an end of an arm to form a weld bead, the method comprising:
extracting a bead formation pass of the weld bead and required conditions for the bead formation pass from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
selecting a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
generating a control command for forming the weld bead at the selected basic position along the bead forming path;
A method for controlling an additive manufacturing apparatus, comprising:
(2) An additive manufacturing device in which a welding torch that melts and solidifies a wire-shaped filler metal while generating an arc is moved by a manipulator held at a tip of an arm to form a weld bead,
a required condition extraction unit that extracts a bead formation path of the weld bead and required conditions required for the bead formation path from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
a basic posture selection unit that selects a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
a control command generating unit that generates a control command for forming the weld bead in the selected basic position along the bead forming path;
An additive manufacturing apparatus comprising:
(3) A program for causing a computer to execute a control procedure for an additive manufacturing device that includes a manipulator having a welding torch held at an end of an arm for melting and solidifying a wire-shaped filler metal while generating an arc, and that moves the welding torch using the manipulator to form a weld bead,
The computer includes:
A function of extracting a bead formation path of the weld bead and required conditions required for the bead formation path from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
a function of selecting a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
a function of generating a control command for forming the weld bead at the selected basic position along the bead forming path;
A program to achieve this.

According to the present invention, even when additive manufacturing of a model using a manipulator with a welding torch attached to its tip, the weld bead can be formed in each additive pass with the manipulator in an appropriate position. This improves modeling accuracy and productivity.

FIG. 1 is a diagram showing the overall configuration of an additive manufacturing apparatus for manufacturing a modeled object. FIG. 2 is a schematic functional block diagram of the control unit. FIG. 3 is an explanatory diagram showing the posture of a welding torch according to a bead formation trajectory of a shaped object. FIG. 4 is an explanatory diagram showing examples of the posture of the welding torch (A) to (E). FIG. 5 is a schematic diagram showing the position of a welding torch during weaving welding. FIG. 6 is a flowchart showing a procedure for selecting an appropriate basic posture of the manipulator and generating a control command. 7A to 7D are explanatory diagrams showing examples of drive configurations of a welding system that includes a welding robot equipped with a welding torch, a positioner device that rotatably supports a workpiece, and a slider device on which the welding robot is placed and which moves the robot horizontally.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
<Configuration of additive manufacturing device>
1 is a diagram showing the overall configuration of an additive manufacturing apparatus 100 for manufacturing a modeled object. The additive manufacturing apparatus 100 includes a modeling unit 11 and a control unit 13 that controls the modeling unit 11.
The manufacturing unit 11 includes a welding robot 17 having a welding torch 15 on its tip axis, a robot driving unit 21 that drives the welding robot 17, a filler metal supply unit 23 that supplies filler metal (welding wire) M to the welding torch 15, and a welding power supply unit 25 that supplies welding current and welding voltage.

(Modeling Department)
The welding robot 17 is an articulated robot, and a filler material M is supported at the tip of a welding torch 15 attached to the tip shaft of the robot arm. The position and posture of the welding torch 15 can be set arbitrarily in three dimensions within the range of the degrees of freedom of the robot arm by commands from a robot driving unit 21. Although not shown, a weaving mechanism for weaving the welding torch 15 may be provided at the tip shaft of the robot arm.

The welding torch 15 has a shield nozzle (not shown) and is a torch for gas metal arc welding to which shielding gas is supplied from the shield nozzle. The arc welding method may be either a consumable electrode type such as shielded metal arc welding or carbon dioxide gas arc welding, or a non-consumable electrode type such as TIG welding or plasma arc welding, and is selected appropriately depending on the additive manufacturing product to be produced.

For example, in the case of a consumable electrode type, a contact tip is placed inside the shield nozzle, and the filler material M to which the welding current is supplied is held by the contact tip. While holding the filler material M, the welding torch 15 generates an arc from the tip of the filler material M in a shielding gas atmosphere.

The filler metal supply unit 23 is equipped with a reel 27 on which the filler metal M is wound. The filler metal M is sent from the filler metal supply unit 23 to a payout mechanism (not shown) attached to a robot arm or the like, and is fed to the welding torch 15 while being fed forward and backward by the payout mechanism as necessary.

Any commercially available welding wire can be used as the filler metal M. For example, welding wires specified in MAG and MIG welding solid wires for mild steel, high tensile steel and low temperature steel (JIS Z 3312), arc welding flux-cored wires for mild steel, high tensile steel and low temperature steel (JIS Z 3313), etc. can be used. Furthermore, filler metals M such as aluminum, aluminum alloys, nickel, nickel-based alloys, etc. can be used depending on the required characteristics.

The robot driver 21 drives the welding robot 17 to move the welding torch 15. As the welding torch 15 moves, the continuously supplied filler metal M is melted by the welding current and welding voltage from the welding power source 25.

In other words, the welding robot 17 is a manipulator that holds a welding torch 15 at the tip of its arm, which generates an arc while melting and solidifying a wire-shaped filler metal M. While the welding torch 15 is moved by driving this manipulator, the filler metal M that is continuously fed to the welding torch 15 is melted and solidified by the arc, and a weld bead B, which is a molten solidified body of the filler metal M, is formed on the base plate 29.

(Control Unit)
The control unit 13 is a computer device including an input/output unit, a storage unit, and a calculation unit (not shown).
The input/output unit is connected to the welding robot 17, the welding power supply unit 25, the filler metal supply unit 23, etc. The memory unit stores various information including a drive program described later. The memory unit is composed of storage such as memory such as ROM and RAM, drive devices such as hard disks and SSDs (Solid State Drives), and storage media such as CDs, DVDs, and various memory cards, and is capable of inputting and outputting various information. A molding program corresponding to a molded object to be manufactured is input to the control unit 13 via a communication line such as a network or various storage media. The molding program is created based on a layering plan that defines a bead formation trajectory and welding conditions for forming a weld bead, and is composed of a large number of command codes.

The control unit 13 executes the modeling program stored in the memory unit, drives the welding robot 17, the filler material supply unit 23, the welding power supply unit 25, etc., and forms the weld bead B according to the modeling program. In other words, the control unit 13 drives the welding robot 17 via the robot drive unit 21 to move the welding torch 15 along the trajectory (welding trajectory) of the welding torch 15 set in the modeling program, and drives the filler material supply unit 23 and the welding power supply unit 25 according to the set welding conditions to melt and solidify the filler material M at the tip of the welding torch 15 by an arc.

In this way, by sequentially forming the weld beads B based on the modeling program, a desired three-dimensional object 30 is created.

The control unit 13 in this configuration has the function of placing the welding robot (manipulator) 17 in an appropriate posture that improves modeling accuracy and productivity according to the bead formation trajectory and welding conditions that form the weld bead defined in the stacking plan.

FIG. 2 is a schematic functional block diagram of the control unit 13. As shown in FIG.
The control unit 13 includes a bead forming path/required condition extraction unit 31, a basic attitude selection unit 33, and a control command generation unit 35, each of which will be described in detail later. The control unit 13 also has a basic attitude database (basic attitude information) 37 in which the basic attitude of the manipulator is registered, and may also have an interlocking information database 39 that associates the basic attitude with a positioner device and a slider device that are provided as necessary, and a simulation unit 34. The interlocking information database 39 and the simulation unit 34 will be described in detail later.

FIG. 3 is an explanatory diagram showing the posture of a welding torch according to a bead formation trajectory of a shaped object.
Since the welding directions TD of the welding passes PS1, PS2, and PS3 that divide the continuous weld line are different, the posture of the welding torch 15 is different for each welding pass. In Fig. 3, the case where the weld bead B is formed by the retreating method is shown, but in the case of the forward method, the inclination angle θ of the welding torch 15 is reversed (inclined on the opposite side to the vertical line).

The welding robot 17 described above sets the welding torch 15 to each posture for each of the welding passes PS1, PS2, and PS3. At that time, the welding robot 17 is a multi-axis robot, and due to its redundant degrees of freedom, there are multiple patterns of the posture of the robot arm (hereinafter referred to as the manipulator posture) even when the welding torch 15 is in the same posture. Each pattern can be selected arbitrarily, and the posture of the welding torch 15 is set to one of the patterns.

The multiple manipulator posture patterns have different characteristics, such as the range of motion of the welding torch 15, the accuracy of the welding target position of the welding torch 15, the accuracy of the bead formation trajectory along which the welding torch 15 moves, and the amount of change in the feed resistance of the filler metal. Therefore, by selecting the optimal pattern from the multiple manipulator posture patterns for each of the welding passes PS1, PS2, and PS3, it is expected that both the molding accuracy and productivity will be improved.

FIG. 4 is an explanatory diagram showing examples of the posture of the welding torch 15 (A) to (E).
The posture of welding torch 15 can be various, such as a state in which the welding torch is arranged vertically with the orientation of the robot arm changed as shown in Figures 4(A) to 4(C), or a state in which the welding torch is tilted from the normal direction to the plate surface of base plate 29 as shown in Figures 4(D) and 4(E). Each posture of the welding torch can be realized by a plurality of manipulator postures that are set within the range of the degrees of freedom of the robot arm.

For example, in the welding path PS1 shown in FIG. 3, the posture of the welding torch 15 is close to that shown in FIG. 4(D), so from among the multiple manipulator postures that correspond to this posture of the welding torch 15, one that is also suitable for the other constraints of the welding path PS1 can be selected.

FIG. 5 is a schematic diagram showing the position of a welding torch during weaving welding.
In the welding path PS1 shown in Fig. 3, for example, when weaving welding is performed as shown in Fig. 5, the posture of the welding torch 15 along the welding direction as shown in Fig. 4C is preferable. Therefore, in this case, a posture that is suitable for other constraint conditions of the welding path PS1 may be selected from among a plurality of manipulator postures corresponding to the postures of the welding torch 15.

The constraints as described above are required for each welding pass such as welding passes PS1, PS2, PS3, etc., and are hereinafter referred to as "required conditions." Required conditions include the bead length along the direction in which the weld bead is formed, the shape accuracy of the weld bead, the additive manufacturing time, the welding conditions, etc. These required conditions can be extracted from the additive manufacturing plan, which indicates the manufacturing procedure for a predetermined object.

<Modeling based on selected basic posture>
Next, a procedure for implementing a stacking plan for stacking a model with an appropriate manipulator posture will be described.
FIG. 6 is a flowchart showing a procedure for selecting an appropriate basic posture of the manipulator and generating a control command.
First, a plurality of basic postures of the welding robot (manipulator) 17 included in the additive manufacturing device 100 shown in FIG. 1 are registered (S1). In this registration process, a plurality of manipulator postures that realize various postures of the welding torch 15 illustrated in FIG. 4 are obtained. Such a manipulator posture is called a "basic posture". Then, the welding robot 17 is associated with the characteristics (the movable range of the welding torch 15, the welding target position accuracy, the accuracy of the bead formation trajectory, the amount of change in the feed resistance of the filler metal, etc., described above) that occur when the welding robot 17 adopts the basic posture, and registered in the basic posture database 37 shown in FIG. 2. Each characteristic may be experimentally or analytically obtained prior to additive manufacturing. For example, element tests such as a BOP (Bead on Plate) welding test can confirm reproducibility and the target position accuracy during modeling. In addition, it is preferable to register the basic posture in association with various characteristics such as the width of the movable range of the welding torch 15 that can be supported. The existence of such association information is helpful when selecting an appropriate basic posture.

Next, the bead formation path/required condition extraction unit 31 extracts the welding path and the required conditions required for that welding path from the lamination plan (S2). The lamination plan includes design information such as the trajectory for moving the welding torch 15 to form the object, the welding conditions, and the filler metal supply speed. The trajectory for moving the welding torch 15 may be extracted by dividing it into sections based on the timing at which the welding direction TD (torch movement direction) changes, as shown in FIG. 3. In that case, the required conditions can be set independently for each of the divided welding paths PS1, PS2, and PS3. The length, range, etc. of the divided welding paths can be set arbitrarily.

Regarding the extraction of required conditions, for example, if the weld bead is to be formed into a wall shape, the shape precision required for wall formation is extracted. As another example, if the inner part surrounded by walls is to be filled with the weld bead, the inclination angle of the welding torch that allows the formation without interfering with the wall is extracted. These required conditions are used to select the basic position during formation. Other required conditions include bead length, formation time (takt time), welding conditions (torch angle and feed speed), etc. The extracted required conditions may be expressed as a vector by combining each condition.

Next, the basic posture selection unit 33 selects a basic posture that satisfies the extracted required conditions (S3). For example, in welding pass PS1, the posture of the welding torch 15 to be applied and the required conditions are obtained from the stacking plan, and candidates for the manipulator posture (basic posture) that corresponds to the welding torch 15 to be set are obtained by referring to the basic posture database 37. Then, from the multiple basic postures obtained, a basic posture that satisfies the required conditions is selected.

Then, the control command generator 35 generates a control command to form a weld bead based on the selected basic position (S4). The generated control command is incorporated into a drive program that instructs a series of operations for performing additive manufacturing.

The above is a basic procedure, but in addition to each piece of basic posture information, for example, as shown in formula (1), weighting with coefficients (Wa, Wb, Wc) may be performed and the integrated evaluation value Y may be stored. Here, three coefficients are used, but this is not limited to this.

Here, e _*,s (*: x, y, z) is the position accuracy of the manipulator tip at a predetermined start point of the weld bead formation (e.g., the difference between a reference set position and the actual tip position), e _*,m (*: x, y, z) is the trajectory tracing accuracy of the manipulator tip during the movement of the welding torch (e.g., the difference between a set trajectory and an actual trajectory), and e _*,f (*: x, y, z) is the position accuracy of the manipulator tip at a predetermined end point of the weld bead formation (e.g., the difference between a set target position and the actual manipulator tip position). In other words, formula 1 is an example of evaluation of the accuracy of the target position related to a series of operations from the start point of the weld bead formation to stacking the weld bead along a specified trajectory to the end point of the formation.

Next, an example of the required condition will be described. Here, the required condition Yg regarding the position accuracy is weighted by coefficients ( _WA , _WB , _WC , ...), and the integrated evaluation value Y is stored together. The number of coefficients is arbitrary.

Here, E _*,s is the required positional accuracy of the manipulator tip at a specified start point of the weld bead formation (e.g., the difference between a reference set position and the actual tip position), E _*,m is the required trajectory tracking accuracy of the manipulator tip during movement of the welding torch (e.g., the difference between a set trajectory and an actual trajectory), and E _*,f is the required positional accuracy of the manipulator tip at a specified end point of the weld bead formation (e.g., the difference between a set target position and the actual manipulator tip position).

When selecting a basic posture that satisfies the above requirements, an evaluation function may be defined and a basic posture that minimizes the evaluation function may be selected. For example, the evaluation function J using Equation 1 and Equation 2 is shown below as an example.

Here, t represents the number of evaluation types. For example, for n types of evaluation values (t = 1 to n), the degree of agreement with the required conditions is the evaluation function J. The smaller this evaluation function J is, the more the basic posture satisfies the required conditions.

After selecting a basic posture that satisfies the required conditions, the operation of the manipulator based on the selected basic posture may be determined and verified by simulation. In this case, the simulation unit 34 shown in FIG. 2 uses information on the basic posture selected by the basic posture selection unit 33 and information based on the stacking plan extracted by the bead formation path/required condition extraction unit 31 to analytically determine the operation of the welding robot 17 that forms a weld bead along the bead formation path in the selected basic posture.

The reproduced operation of the welding robot 17 may have multiple patterns depending on the redundant degrees of freedom of the multi-axis robot. Among these multiple operation patterns, there may be a unique posture/state (unacceptable posture) that should be avoided, so it is preferable to extract operation patterns that cause such unacceptable postures in advance and register them in the basic posture database 37. In this way, when the basic posture selection unit 33 selects a basic posture, the basic postures that include the unacceptable posture in the operation pattern can be excluded from the options. Specifically, a motion pattern is obtained by simulation using the selected basic posture, and it is determined whether the result includes the previously registered unacceptable posture. If it is determined that the unacceptable posture is included, the selected basic posture is corrected to another basic posture. In this way, by reproducing the operation pattern of the welding robot 17 by simulation, it is possible to select an operation of the welding robot 17 that does not include the unacceptable posture. The calculation of the simulation can be performed by commercially available general-purpose software.

<Interlocking of positioner device and slider device>
Next, a case where a positioner device and a slider device are used in conjunction with the welding robot 17 to perform shaping will be described.
7A to 7D are explanatory diagrams showing examples of drive modes of a welding system 200 including a welding robot 17 equipped with the above-mentioned welding torch 15, a positioner device 41 that rotatably supports the workpiece W, and a slider device 43 on which the welding robot 17 is placed and which moves it horizontally.

In the case shown in FIG. 7, in addition to the basic posture of the manipulator (welding robot 17), the conditions (interlocking information) for interlocking the positioner device 41 and slider device 43 with the welding robot 17 are combined and selected. In other words, the interlocking information with the positioner device 41 and slider device 43 is combined with the basic posture information and registered in the database. In this case, the number of types of basic postures increases, improving the freedom of posture selection.

The specific driving modes of each device are as follows.
7A, the welding robot 17 and the slider device 43 are fixed, and only the positioner device 41 is rotationally driven. Since only the positioner is operated, there is little deviation in the target position of the welding torch 15, and the weld bead B can be formed along the circumferential direction on the peripheral surface of the workpiece W with high shaping accuracy.
7B, the welding robot 17 is kept fixed, the positioner device 41 is rotated, and the slider device 43 is driven. In this way, the operation of the slider is essentially the same as moving the welding torch 15 in the left-right and depth directions. Therefore, the range of motion of the torch when forming the weld bead B on the peripheral surface of the workpiece W can be expanded.
7C, the positioner device 41 and the slider device 43 are kept fixed, and only the welding robot 17 is driven. Since only the welding robot 17 is operated, the target position can be precisely adjusted, and the weld bead B can be formed on the peripheral surface of the workpiece W with good shaping accuracy.
7D, the slider device 43 is kept fixed, and the welding robot 17 is driven to rotate the positioner device 41. Compared to the case of Fig. 7C, the addition of rotation of the positioner device 41 improves the flexibility of the range in which lamination can be performed and the postures that can be taken, widening the range of motion of the torch and improving production efficiency.

The results of comparing the modeling accuracy, production efficiency, and range of motion of the welding torch for the drive modes (A) to (D) in Figure 7 are shown in Table 1. In the table, "○" indicates good results, and "△" indicates that there is a deterioration or restriction.

In the drive modes shown in (A) to (D) of FIG. 7, the characteristics such as the molding accuracy, production efficiency, and the range of motion of the welding torch differ for each drive mode. Therefore, the basic posture and interlocking information are selected so that the characteristics to be prioritized for each welding pass are reliably obtained. The above characteristics are only an example, and there may be other characteristics such as the position adjustment accuracy of the positioner device and slider device, and the compatible movement speed.

In this way, the basic posture and interlocking information are combined and registered in the interlocking information database 39. This increases the variety of basic postures and interlocking information, improving the freedom of selection. In addition, depending on the combination of postures and states of the welding robot 17, the positioner device 41, and the slider device 43, a unique combination (also referred to as an "unacceptable posture") that should be avoided may occur. Therefore, by registering such unique combinations in advance in the interlocking information database 39, options that include unacceptable postures can be excluded when the basic posture selection unit 33 selects a basic posture.

For example, if there is a requirement to keep the torch angle tilted at a fixed angle when forming a weld bead, the inclination angle of the welding torch relative to the welding direction can be the same for each pass, as in the cases of (A) and (B) in Figure 7. Also, if priority is given to shape accuracy while also taking into account the characteristics of the positioner device 41 and slider device 43, (A) of (A) and (B) in Figure 7 can be selected, and if priority is given to production efficiency (production speed), (C) of (C) and (D) in Figure 7 can be selected, etc.

As described above, even when additive manufacturing of a model using a manipulator with a welding torch attached to its tip, the weld bead can be formed in each additive pass with the manipulator in an appropriate position. This improves modeling accuracy and productivity.

The present invention is not limited to the above-described embodiments, and it is intended that the various configurations of the embodiments be combined with each other, and that those skilled in the art may modify and apply the invention based on the description in the specification and well-known techniques, and this is included in the scope of the protection sought.

As described above, the present specification discloses the following:
(1) A method for controlling an additive manufacturing device in which a welding torch that melts and solidifies a wire-shaped filler metal while generating an arc is moved by a manipulator held at an end of an arm to form a weld bead, the method comprising:
extracting a bead formation pass of the weld bead and required conditions for the bead formation pass from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
selecting a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
generating a control command for forming the weld bead at the selected basic position along the bead forming path;
A method for controlling an additive manufacturing apparatus comprising the steps of:
According to this method for controlling an additive manufacturing apparatus, the formation of a weld bead can be performed with the manipulator in an appropriate posture, thereby improving both the manufacturing accuracy and productivity.

(2) The method for controlling an additive manufacturing device according to (1), wherein the basic posture information includes any one of a movable range of the welding torch by the manipulator, a welding target position accuracy of the welding torch, an accuracy of a bead formation trajectory along which the welding torch moves, and an amount of change in feed resistance of the filler metal.
According to this method for controlling an additive manufacturing apparatus, these pieces of information are associated with each basic posture, making it easier to select an appropriate basic posture.

(3) the required conditions include any one or a combination of a bead length along a formation direction of the weld bead, a shape accuracy of the weld bead, an additive manufacturing time, and a welding condition,
The control method for an additive manufacturing apparatus according to (1) or (2), wherein in the selection of the basic posture, a basic posture of the manipulator that satisfies the required condition is selected.
According to this control method for an additive manufacturing device, the basic posture is selected taking into consideration the bead length that the basic posture can accommodate, the shape accuracy that can be guaranteed, and the like, thereby making it possible to suppress excessive burden on the manipulator.

(4) determining, by simulation, an operation of the manipulator for forming the weld bead along the bead formation path in the selected basic posture;
determining whether the motion of the manipulator obtained by the simulation includes an unacceptable posture of the manipulator that has been registered in advance;
A control method for an additive manufacturing device described in any one of (1) to (3), comprising a step of correcting the selected basic posture to another basic posture when it is determined that the selected basic posture includes an unacceptable posture.
According to this method for controlling an additive manufacturing apparatus, it is possible to prevent modeling from occurring in a posture that places a large load on the manipulator or that is difficult for the manipulator to handle.

(5) The method for controlling an additive manufacturing device according to any one of (1) to (4), wherein the basic attitude information further includes linkage information between the manipulator and at least one of a slider device that moves the manipulator and a positioner device that supports a base on which the weld bead is formed.
According to this method for controlling an additive manufacturing apparatus, by further including linkage information with the slider and positioner, the number of possible basic postures is increased, improving the degree of freedom in selecting the basic posture.

(6) An additive manufacturing device in which a welding torch that melts and solidifies a wire-shaped filler metal while generating an arc is moved by a manipulator held at a tip of an arm to form a weld bead,
a required condition extraction unit that extracts a bead formation path of the weld bead and required conditions required for the bead formation path from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
a basic posture selection unit that selects a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
a control command generating unit that generates a control command for forming the weld bead in the selected basic position along the bead forming path;
An additive manufacturing apparatus comprising:
According to this additive manufacturing device, the formation of a weld bead can be performed with the manipulator in an appropriate position, thereby improving both the manufacturing accuracy and productivity.

(7) A program for causing a computer to execute a control procedure for an additive manufacturing device that includes a manipulator having a welding torch held at an end of an arm for melting and solidifying a wire-shaped filler metal while generating an arc, and that moves the welding torch using the manipulator to form a weld bead,
The computer includes:
A function of extracting a bead formation path of the weld bead and required conditions required for the bead formation path from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
a function of selecting a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
a function of generating a control command for forming the weld bead at the selected basic position along the bead forming path;
A program to achieve this.
According to this program, the weld bead can be formed with the manipulator in an appropriate posture, thereby improving both the molding accuracy and productivity.

REFERENCE SIGNS LIST 11 Modeling section 13 Control section 15 Welding torch 17 Welding robot 21 Robot driving section 23 Filler metal supply section 25 Welding power supply section 27 Reel 29 Base plate 30 Modeled object 31 Bead formation path/required condition extraction section 33 Basic posture selection section 34 Simulation section 35 Control command generation section 37 Basic posture database 39 Interlocking information database 41 Positioner device 43 Slider device 100 Additive manufacturing device 200 Welding system B Weld bead M Filler metal PS1, PS2, PS3 Welding path TD Welding direction W Work θ Tilt angle

Claims (5)

A method for controlling an additive manufacturing apparatus in which a welding torch that melts and solidifies a wire-shaped filler metal while generating an arc is moved by a manipulator held at a tip of an arm to form a weld bead, the method comprising:
extracting a bead formation pass of the weld bead and required conditions for the bead formation pass from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
selecting a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
generating a control command for forming the weld bead at the selected basic position along the bead forming path;
the basic posture information includes any one of a movable range of the welding torch by the manipulator, a welding target position accuracy of the welding torch, an accuracy of a bead formation trajectory along which the welding torch moves, and an amount of change in feed resistance of the filler metal;
the required conditions include any one or a combination of a bead length along a formation direction of the weld bead, a shape accuracy of the weld bead, an additive manufacturing time, and a welding condition;
In the step of selecting the basic posture, when selecting the basic posture of the manipulator that satisfies the required condition, a basic posture is selected such that an evaluation function J shown in the following formula is minimized.
A method for controlling an additive manufacturing device.

however,
t: number of evaluation types Y: evaluation value of basic posture information Yg: evaluation value of required conditions
W _a , W _b , W _c , W _A , W _B , W _C : coefficients
e _*,s (*: x, y, z): Difference between the reference set position, which is the start point of the formation of the weld bead, and the actual position of the tip of the manipulator
e _*,m (*: x, y, z): Difference between the set trajectory and the actual trajectory of the tip of the manipulator
e _*,f (*: x, y, z): Difference between the set target position, which is the end point of the weld bead formation, and the actual manipulator tip position
E _*,s (*: x, y, z): Difference between the reference set position, which is the start point of the formation of the weld bead, and the actual tip position of the manipulator tip
E _*,m (*: x, y, z): Difference between the set trajectory and the actual trajectory of the tip of the manipulator
E _*,f (*: x, y, z): Difference between the set target position, which is the end point of the weld bead formation, and the actual manipulator tip position determining, by simulation, an operation of the manipulator for forming the weld bead along the bead formation path in the selected basic posture;
determining whether the motion of the manipulator obtained by the simulation includes an unacceptable posture of the manipulator that has been registered in advance;
modifying the selected basic posture to another basic posture when it is determined that the unacceptable posture is included;
The method for controlling the additive manufacturing apparatus according to claim 1 . The method for controlling an additive manufacturing device according to claim 1 or 2, wherein the basic attitude information further includes linkage information between the manipulator and at least one of a slider device that moves the manipulator and a positioner device that supports a base on which the weld bead is formed. A manipulator having a welding torch at an end of an arm, the welding torch melting and solidifying a wire-shaped filler metal while generating an arc, moves the welding torch to form a weld bead,
a required condition extraction unit that extracts a bead formation path of the weld bead and required conditions required for the bead formation path from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
a basic posture selection unit that selects a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
a control command generating unit that generates a control command for forming the weld bead in the selected basic position along the bead forming path;
Equipped with
the basic posture information includes any one of a movable range of the welding torch by the manipulator, a welding target position accuracy of the welding torch, an accuracy of a bead formation trajectory along which the welding torch moves, and an amount of change in feed resistance of the filler metal;
the required conditions include any one or a combination of a bead length along a formation direction of the weld bead, a shape accuracy of the weld bead, an additive manufacturing time, and a welding condition;
When selecting a basic posture of the manipulator that satisfies the required condition, the basic posture selection unit selects a basic posture that minimizes an evaluation function J shown in the following equation:
Additive manufacturing equipment.

however,
t: number of evaluation types Y: evaluation value of basic posture information Yg: evaluation value of required conditions
W _a , W _b , W _c , W _A , W _B , W _C : coefficients
e _*,s (*: x, y, z): Difference between the reference set position, which is the start point of the formation of the weld bead, and the actual position of the tip of the manipulator
e _*,m (*: x, y, z): Difference between the set trajectory and the actual trajectory of the tip of the manipulator
e _*,f (*: x, y, z): Difference between the set target position, which is the end point of the weld bead formation, and the actual manipulator tip position
E _*,s (*: x, y, z): Difference between the reference set position, which is the start point of the formation of the weld bead, and the actual tip position of the manipulator tip
E _*,m (*: x, y, z): Difference between the set trajectory and the actual trajectory of the tip of the manipulator
E _*,f (*: x, y, z): Difference between the set target position, which is the end point of the weld bead formation, and the actual manipulator tip position A program for causing a computer to execute a control procedure for an additive manufacturing device that includes a manipulator having a welding torch held at an end of an arm, the welding torch melting and solidifying a wire-shaped filler metal while generating an arc, and that moves the welding torch using the manipulator to form a weld bead,
The computer includes:
A function of extracting a bead formation path of the weld bead and required conditions required for the bead formation path from a lamination plan that defines a bead formation trajectory and welding conditions for forming the weld bead;
a function of selecting a basic posture of the manipulator that is suitable for the required conditions from basic posture information in which a plurality of basic postures of the manipulator corresponding to the posture of the welding torch are registered;
a function of generating a control command for forming the weld bead at the selected basic position along the bead forming path;
Realize this,
the basic posture information includes any one of a movable range of the welding torch by the manipulator, a welding target position accuracy of the welding torch, an accuracy of a bead formation trajectory along which the welding torch moves, and an amount of change in feed resistance of the filler metal;
the required conditions include any one or a combination of a bead length along a formation direction of the weld bead, a shape accuracy of the weld bead, an additive manufacturing time, and a welding condition;
The function of selecting the basic posture is a function of selecting a basic posture such that an evaluation function J shown in the following formula is minimized when selecting a basic posture of the manipulator that satisfies the required conditions.
program.

however,
t: number of evaluation types Y: evaluation value of basic posture information Yg: evaluation value of required conditions
W _a , W _b , W _c , W _A , W _B , W _C : coefficients
e _*,s (*: x, y, z): Difference between the reference set position, which is the start point of the formation of the weld bead, and the actual position of the tip of the manipulator
e _*,m (*: x, y, z): Difference between the set trajectory and the actual trajectory of the tip of the manipulator
e _*,f (*: x, y, z): Difference between the set target position, which is the end point of the weld bead formation, and the actual manipulator tip position
E _*,s (*: x, y, z): Difference between the reference set position, which is the start point of the formation of the weld bead, and the actual tip position of the manipulator tip
E _*,m (*: x, y, z): Difference between the set trajectory and the actual trajectory of the tip of the manipulator
E _*,f (*: x, y, z): Difference between the set target position, which is the end point of the weld bead formation, and the actual manipulator tip position

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