Robot control device, control method, and program

Abstract

To enable automatically adjusting a posture parameter so as to avoid interference between a welding torch and a molded article in laminate molding.SOLUTION: A control device of a robot performing laminate molding by using a welding torch includes: acquisition means of acquiring shape information of a molded article, torch information of the welding torch, and manipulation information of the welding torch in laminate molding; generation means of generating an interference map which indicates a position of the welding torch, where interference between the molded article and the welding torch is generated, and a parameter of a posture on the basis of the shape information and the torch information; identifying means of identifying a position where interference between the welding torch and the molded article is generated on the basis of the interference map, and the position and posture of the welding torch regulated by the manipulation information; and adjustment means of adjusting the parameter of the posture of the welding torch in the position identified by the identifying means.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The present invention relates to a control device, a control method, and a program for a robot.

Background Art

[0002] Conventionally, a laminated object has been formed by laminating welding beads using a robot. When welding is performed automatically, an operator teaches the welding path and posture in advance. When performing laminated modeling, it is necessary to control the posture in consideration of the shape and position of the already formed welding beads and the base material.

[0003] For example, Patent Document 1 discloses a configuration in which a welding torch is modeled, and an angle at which the welding torch does not collide with the formed object is calculated at each target position on the path to set the torch angle. Further, Patent Document 2 discloses a configuration in which interference is determined using a table that defines the relationship between the welding torch posture and the position of the torch.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] During additive manufacturing, if the welding torch of the additive manufacturing apparatus collides with or interferes with the base material or the additive manufactured object, not only will the manufacturing be interrupted, but it may also take a long time to restore the apparatus in order to perform the additive manufacturing again. Therefore, it is necessary to control to avoid collisions and interferences during additive manufacturing. However, if interference determination is performed for each of a plurality of points constituting the trajectory of the welding torch with respect to the distance between the welding torch and the base material in three-dimensional space, it will take an enormous amount of time. Furthermore, in such interference determination processing, omissions can also occur.

[0006] Also, interference determination can be performed based on the distance between the welding torch and the base. However, based on the result, it is also necessary to correct and set the posture of in which direction the welding torch should avoid. Such determination of interference of the welding torch and setting of avoidance conditions require a great deal of labor from the user. Therefore, in addition to the interference determination of the welding torch related to additive manufacturing, a method for automatically adjusting the posture of the welding torch has been demanded.

[0007] In view of the above problems, an object of the present invention is to enable automatic adjustment of posture parameters so as to avoid interference between the welding torch and the manufactured object in additive manufacturing.

Means for Solving the Problems

[0008] In order to solve the above problems, the present invention has the following configuration. That is, a control device for a robot that performs additive manufacturing using a welding torch, an acquisition means for acquiring shape information of the manufactured object, torch information of the welding torch, and torch movement information of the welding torch during the additive manufacturing; a generation means for generating an interference map showing parameters of the position and posture of the welding torch at which interference occurs between the manufactured object and the welding torch based on the shape information and the torch information; a specifying means for specifying a position at which interference occurs between the welding torch and the manufactured object based on the interference map and the position and posture of the welding torch defined by the torch movement information; Adjusting means for adjusting parameters of the posture of the welding torch at the position specified by the specific means; having; The interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system; The specific means specifies, as parameters to be corrected, parameters of the posture at the position where interference occurs on any one of the plurality of axes.

[0009] Further, as another aspect of the present invention, it has the following configuration. That is, a control method for a robot that performs additive manufacturing using a welding torch, comprising: An acquisition step of acquiring shape information of a workpiece, torch information of the welding torch, and torch movement information of the welding torch during the additive manufacturing; A generation step of generating an interference map showing parameters of the position and posture of the welding torch at which interference occurs between the workpiece and the welding torch based on the shape information and the torch information; A specific step of specifying a position where interference occurs between the welding torch and the workpiece based on the interference map and the position and posture of the welding torch defined by the torch movement information; An adjustment step of adjusting parameters of the posture of the welding torch at the position specified in the specific step; having; The interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system; In the specific step, parameters of the posture at the position where interference occurs on any one of the plurality of axes are specified as parameters to be corrected.

[0010] Further, as another aspect of the present invention, it has the following configuration. That is, a program, comprising: causing a computer to perform an acquisition step of acquiring shape information of a workpiece, torch information of a welding torch, and torch movement information of the welding torch during additive manufacturing; A generation step of generating an interference map showing parameters of the position and orientation of the welding torch at which interference occurs between the shaped object and the welding torch based on the shape information and the torch information; An identification step of identifying a position where interference occurs between the welding torch and the shaped object based on the interference map and the position and orientation of the welding torch defined by the torch movement information; An adjustment step of adjusting the parameter of the orientation of the welding torch at the position identified in the identification step; To cause to execute, The interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system, In the identification step, the parameter of the orientation of the position where interference occurs on any one of the plurality of axes is identified as a parameter to be corrected.

Advantages of the Invention

[0011] According to the present invention, it becomes possible to automatically adjust the attitude parameter so as to avoid interference between the welding torch and the shaped object in layered manufacturing.

Brief Description of the Drawings

[0012]

Figure 1

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Figure 11

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings and the like. Note that the embodiments described below are merely examples for explaining the present invention and are not intended to limit the interpretation of the present invention. Also, not all the configurations described in each embodiment are essential for solving the problems of the present invention. In each drawing, the same reference numerals are assigned to the same components to indicate the correspondence.

[0014] <First Embodiment> Hereinafter, the first embodiment of the present invention will be described. Here, a layer forming system capable of executing layer forming will be described as an example. However, the present invention is not limited thereto as long as it is a configuration capable of implementing the essential part of the present invention.

[0015] [System Configuration] FIG. 1 is a schematic configuration diagram of a layer forming system to which the present invention is applicable.

[0016] The additive manufacturing system 1 according to this embodiment includes an additive manufacturing apparatus 100 and an information processing apparatus 200 that comprehensively controls the additive manufacturing apparatus 100. In FIG. 1, a three-dimensional coordinate system indicated by the X-axis, Y-axis, and Z-axis is shown. The origin position of the three-dimensional coordinate system is not particularly limited, but an arbitrary position is set, and based on this origin position, the additive manufacturing system 1 performs an additive manufacturing operation.

[0017] The additive manufacturing apparatus 100 includes a welding robot 104, a filler material supply unit 105 that supplies a filler material (welding wire) M to a torch 102, a robot controller 106 that controls the welding robot 104, and a power source 107.

[0018] The welding robot 104 is an articulated robot, and the filler material M is supported so as to be continuously supplied to the torch 102 provided at the tip axis. The torch 102 holds the filler material M in a state of protruding from the tip. The position and orientation of the torch 102 can be arbitrarily set three-dimensionally within the range of the degrees of freedom of the robot arm constituting the welding robot 104.

[0019] The torch 102 has a shielding nozzle (not shown), and shielding gas is supplied from the shielding nozzle. The shielding gas blocks the atmosphere, prevents oxidation, nitridation, etc. of the molten metal during welding, and suppresses welding defects. As the arc welding method used in this embodiment, either a consumable electrode type such as covered arc welding or carbon dioxide arc welding, or a non-consumable electrode type such as TIG welding or plasma arc welding may be used, and it is appropriately selected according to the additive manufactured object W to be manufactured.

[0020] In the vicinity of the torch 102, a shape sensor 101 that can move following the movement of the torch 102 is provided. The shape sensor 101 detects the shape of the laminated object W formed on the base 103. In the present embodiment, it is assumed that the shape sensor 101 can detect the height, position, width, etc. of the welding bead 108 (also simply referred to as "bead") that constitutes the laminated object W. The information detected by the shape sensor 101 is transmitted to the information processing device 200. Note that the configuration of the shape sensor 101 is not particularly limited, and it may be a configuration that detects the shape by contact (contact type sensor), or a configuration that detects the shape by laser or the like (non-contact type sensor). Note that the means for deriving the shape of the formed bead is not limited to the shape sensor 101 installed in the vicinity of the torch 102. For example, a configuration that indirectly derives the shape of the formed bead may be used. As an example, a profile of the welding current and the feeding speed of the filler metal M and a DB (database) indicating the tendency of the bead height are defined in advance, and the height of the formed bead is derived based on the welding conditions during shaping.

[0021] In the welding robot 104, when the arc welding method is a consumable electrode type, a contact tip is disposed inside the shield nozzle, and the filler metal M to which the melting current is supplied is held by the contact tip. The torch 102 generates an arc from the tip of the filler metal M in a shielding gas atmosphere while holding the filler metal M. The filler metal M is fed from the filler metal supply unit 105 to the torch 102 by a feeding mechanism (not shown) attached to a robot arm or the like. Then, while moving the torch 102, when the continuously fed filler metal M is melted and solidified, a linear welding bead 108 that is a molten solid of the filler metal M is formed on the base 103. By laminating the welding beads 108, the laminated object W is shaped.

[0022] Note that the heat source for melting the filler material M is not limited to the above-described arc. For example, other heat source methods such as a heating method that combines an arc and a laser, a heating method using plasma, a heating method using an electron beam or a laser, etc. may be adopted. When heating with an electron beam or a laser, the heating amount can be controlled more finely, the state of the weld bead 108 can be maintained more appropriately, and it can contribute to further quality improvement of the laminated object W.

[0023] The robot controller 106 drives the welding robot 104 by a predetermined drive program based on an instruction from the information processing device 200, and forms the laminated object W on the base 103. That is, the welding robot 104 moves the torch 102 while melting the filler material M with an arc according to a command from the robot controller 106. The power source 107 is a welding power source that supplies the power required for welding to the robot controller 106. The power source 107 is operable in a plurality of control modes, and can switch the power (such as current and voltage) at the time of power supply to the robot controller 106 according to the control mode. The filler material supply unit 105 controls the supply and feeding speed of the filler material M to the torch 102 of the welding robot 104 based on an instruction from the information processing device 200.

[0024] The information processing device 200 may be, for example, an information processing device such as a PC (Personal Computer). Each function shown in FIG. 1 may be realized by a control unit (not shown) reading and executing a program of the functions according to the present embodiment stored in a storage unit (not shown). As the storage unit, a RAM (Random Access Memory) which is a volatile storage area, a ROM (Read Only Memory), an HDD (Hard Disk Drive), etc. which are non-volatile storage areas may be included. As the control unit, a CPU (Central Processing Unit), a GPU (Graphical Processing Unit), or a GPGPU (General-Purpose computing on Graphics Processing Units) etc. may be used.

[0025] The information processing apparatus 200 includes a shaping control unit 201, a power supply control unit 202, a feeding control unit 203, a DB management unit 204, a shape data acquisition unit 205, an instruction data acquisition unit 206, a parameter adjustment unit 207, and a peripheral device control unit 208. The shaping control unit 201 generates a control signal for the robot controller 106 during shaping based on the design data (e.g., CAD / CAM data, etc.) of the laminated object W to be shaped. The control signal here includes the movement trajectory of the torch 102 by the welding robot 104, the welding conditions during the formation of the welding bead 108, the feeding speed of the filler material M by the filler material supply unit 105, and the like. The movement trajectory of the torch 102 is not limited to the trajectory of the torch 102 during the formation of the welding bead 108 on the base 103, and includes, for example, the movement trajectory of the torch 102 to the start position for forming the welding bead 108.

[0026] The power supply control unit 202 controls the power supply (control mode) from the power supply 107 to the robot controller 106. Depending on the control mode, the values of the current and voltage, the waveform (pulse) of the current, etc. when forming beads of the same shape may also be different. Also, the power supply control unit 202 timely acquires information on the current and voltage provided from the power supply 107 to the robot controller 106.

[0027] The feeding control unit 203 controls the feeding speed and feeding timing of the filler material M by the filler material supply unit 105. The feeding control of the filler material M here includes not only feeding out (forward feeding) but also feeding back (reverse feeding). The DB management unit 204 manages the DB (database) according to this embodiment. The DB according to this embodiment includes, for example, information regarding the shape of the bead as the shaping result for each pass. Here, the pass corresponds to the path of the torch 102 during the shaping of the laminated object. The shape data acquisition unit 205 acquires the shape data of the welding bead 108 formed on the base 103 detected by the shape sensor 101.

[0028] The teaching data acquisition unit 206 acquires teaching data including parameters taught by an operator via, for example, a teaching pendant (not shown). The layer forming control unit 201 can form the laminated object W by controlling the welding robot 104 using the design data of the laminated object W and the teaching data. In the present embodiment, these data are also collectively referred to as "lamination plan data". Note that the data included in the lamination plan data is not particularly limited. The parameter adjustment unit 207 determines interference between the torch 102 and the formed object or the like by a process described later, and calculates parameters for adjusting the posture of the torch 102. The lamination plan data is adjusted based on the parameters calculated by the parameter adjustment unit 207.

[0029] The peripheral device control unit 208 controls the operations of the peripheral devices provided around the welding robot 104 included in the layer forming system 1. Although not shown in FIG. 1, examples of the peripheral devices include a positioner for adjusting the position and posture of the base 103 on which the laminated object W is formed, and a slider capable of sliding the welding robot 104 in a predetermined direction. Therefore, the welding robot 104 may perform the layer forming operation in conjunction with these peripheral devices.

[0030] In addition, the coordinate system in the design data according to the present embodiment is associated with the coordinate system of the welding robot 104, and it is assumed that the three axes (X-axis, Y-axis, Z-axis) of the coordinate system are set so that the position in three dimensions is defined with an arbitrary position as the origin.

[0031] The layer forming system 1 having the above configuration moves the torch 102 by driving the welding robot 104 while melting the filler metal M and supplying the melted filler metal M onto the base 103 in accordance with the movement locus of the torch 102 defined by the lamination plan data and the parameters calculated according to the result of the interference determination. As a result, a laminated object W in which a plurality of linear welding beads 108 are arranged and laminated on the upper surface of the base 103 is formed.

[0032] [Interference determination] Figure 2 is a schematic diagram showing an example of the shape of the tip of the torch 102. The tip of the torch 102 is tapered, with the width at the foremost end being W1, and as it moves away from the tip, it reaches the maximum width W2. The length of this tapered portion is denoted as L. For example, it may be configured with W1 = 20 [mm], W2 = 25 [mm], and L = 21.5 [mm]. Information such as the torch nozzle diameter and the length of the nozzle for the torch 102 used in additive manufacturing is managed in advance as torch information.

[0033] Figure 3 is a conceptual diagram for explaining the concept of interference determination between the torch 102 and the base material or the additive manufactured object. Here, the torch 102 is modeled at a plurality of points, and its foremost end is indicated as point 102a. Also, the surface of the base material 300, etc. is modeled at a plurality of points (for example, point 301). Here, the torch 102, the base material 300, and the manufactured object are composed of points at regular intervals, but the interval between these points is not particularly limited.

[0034] For example, as shown in Figure 3, interference determination is performed by determining the distance in the three-dimensional space between the points constituting the torch 102 and the points constituting the base material or the manufactured object. For example, a certain threshold value may be set for the distance between points, and when the distance is equal to or less than the threshold value, it may be determined that there is interference.

[0035] Figure 4 is a conceptual diagram showing the space in which the torch 102 is located in the three-dimensional space based on the configuration example of the torch 102 shown in Figure 2. Here, a three-dimensional coordinate system is shown with the x-axis, y-axis, and z-axis, and it is assumed that the torch 102 is located there. The torch 102 is modeled as shown in Figure 3, and the region occupied by the torch 102 is used for interference determination. Region R indicates the region that is treated as the region where the torch 102 is located within the three-dimensional space. Here, region R is shown in a cylindrical shape as the space inscribed by the torch 102, but it may be other shapes. Regarding region R, the length (diameter) in the x-axis direction is denoted as Lx, and the length (diameter) in the y-axis direction is denoted as Ly. Here, the z-direction is omitted, but it can be defined in the same way.

[0036] The area R can vary depending on the shape, position, and orientation of the torch 102. Also, the area R may be set in consideration of the moving direction of the torch 102.

[0037] FIG. 5 is a diagram for explaining interference during additive manufacturing. Here, it is a view seen from the horizontal direction along the x-axis direction, with the horizontal direction as the y-axis and the height direction as the z-axis. An example is shown where a base material 300 is arranged around the torch 102 and beads 350 are formed in 4 layers (4 passes). Note that in FIG. 5, the shape of the tip of the torch 102 is used for explanation, but interference determination may be performed with a cylindrical configuration corresponding to the shape of the torch 102 as in the area R of FIG. 4.

[0038] Here, let the position of the x-coordinate (depth direction in the drawing) of the torch be x t (x = x t ). Also, let the rotation angle of the torch 102 around the x-axis be indicated by θx. Also, let the position of the end of the bead 350 in the y-axis direction be shown as y B . Further, let the position of the end of the torch 102 in the y-axis direction be shown as y T . At this time, y T may be specified based on the value of the torch 102 in the y-axis direction corresponding to the height (value in the z-axis direction) of the bead 350.

[0039] In the interference determination, in the case of the example in FIG. 5, it can be handled as follows. y T > y B : No interference y T = y B : Interference boundary (can be determined as having interference) y T <y B : Interference

[0040] FIG. 6 shows another example when performing an additive manufacturing operation in a three-dimensional coordinate system. Similar to FIG. 5, an example is shown where a base material 300 is arranged around the torch 102 and beads 350 are formed in 5 layers (5 passes). Also, the three-dimensional coordinate system and the rotation angles θ x , θ y , θz is shown. Here, the torch 102 shows an example of moving along the x-axis direction.

[0041] In order to avoid interference between the torch 102 during additive manufacturing and the base material 300 or the bead 350, the torch 102 needs to adjust its posture according to the moving position. In particular, for the bead 350, since its shape (width and height) changes as the additive manufacturing progresses, it is necessary to control the posture of the torch 102 in response to such changes.

[0042] In this embodiment, a map (hereinafter referred to as an "interference map") that defines the control parameters of the position and posture of the torch 102 where interference occurs between the torch 102 and the base material or bead located around it for each path of the torch 102 is used to adjust the control parameters of the torch 102 based on the additive manufacturing plan data. The control parameters to be adjusted here include the posture of the torch 102, that is, the rotation angle around the three-dimensional coordinate axes defined corresponding to the three-dimensional space. That is, the interference / non-interference between the base material or bead and the torch 102 at a certain target position changes according to the position of the base material or bead and the position and posture of the torch 102.

[0043] FIG. 7 is a diagram showing an example of the relationship between the interference map and the rotation angle θ of the torch 102 around the x-axis x and. Here, the values of the y-axis and z-axis are fixed. In FIG. 7, the horizontal axis represents the value of x on the x-axis, and the vertical axis represents the rotation angle θ around the x-axis x is shown. Also, on the interference map, the regions of the base material 300 and the bead 350 are shown. Further, the line 400 represents the rotation angle θ at the x-coordinate of the torch x is shown.

[0044] Here, the posture parameters (x, θ x ) where the region of the base material 300 or the bead 350 overlaps with the line 400 mean that the torch 102 interferes with the base material 300 or the bead 350. Therefore, it is necessary to adjust the parameters so that they do not interfere.

[0045] In the example of FIG. 7, the process of adjusting parameters in order from the top is shown. First, line 400 indicates the initial value. Then, as shown by line 401, adjustment is made so that interference does not occur. The adjustment method is not particularly limited. For example, the adjustment may be configured to change the rotation angle of the interfering position to the interference boundary (hereinafter, also referred to as the "interference boundary") so that interference does not occur, or the rotation angle that is the midpoint of the region where no interference occurs at a certain x-axis value may be used. Alternatively, adjustment may be made using a preset offset value.

[0046] Furthermore, as shown by line 402, smoothing processing is performed. The method of smoothing is not particularly limited. For example, the smoothing processing may be performed so that the difference in the rotation angle θ of consecutive positions is within a predetermined range. Thereby, a sudden change in the rotation angle during the movement of the torch 102 can be suppressed.

[0047] FIG. 8, similar to FIG. 7, shows a configuration example of an interference map. The horizontal axis indicates the value of the coordinate axis (here, the x-axis), and the vertical axis indicates the rotation angle around the coordinate axis (here, the rotation angle θ x ). Also, region 801 corresponds to the base material, and region 802 corresponds to the bead. The interference map is provided for each axis and further for each pass. That is, when the laminated object is formed in 10 passes, 3 (corresponding to the three axes of the x-axis, y-axis, and z-axis) × 10 (corresponding to each of the 10 passes) = 30 interference maps are used.

[0048] FIGS. 9A to 9C show examples of interference maps corresponding to each axis provided corresponding to one pass. In the following example, the case of adjusting the rotation angle θ x around the x-axis will be described. In this example, as shown in FIG. 6, it is assumed that shaping is performed along the x-axis direction, and therefore, the values of the y-axis and the z-axis are fixed. Accordingly, which parameter among the three axes is adjusted depends appropriately on the shaping direction of the pass (the moving direction of the torch 102).

[0049] Figure 9A is an interference map corresponding to the x-axis direction, showing the state where the line 903, which is the initial value, is set. The horizontal axis represents the values on the x-axis, and the vertical axis represents the rotation angle around the x-axis. The initial value may be defined in advance or specified in the lamination plan data or the like. Region 901 corresponds to the base material, and region 902 corresponds to the bead that has been formed at that time.

[0050] Figure 9B is an interference map corresponding to the y-axis, showing the state where the point 913, which is the initial value, is set. As described above, since the value of the y-axis and the rotation angle θ around the y-axis y are fixed, they are shown as points. The horizontal axis represents the values on the y-axis, and the vertical axis represents the rotation angle around the y-axis. The initial value may be defined in advance or specified in the lamination plan data or the like. Region 911 corresponds to the base material, and region 912 corresponds to the bead that has been formed at that time.

[0051] Figure 9C is an interference map corresponding to the z-axis, showing the state where the point 923, which is the initial value, is set. As described above, since the value of the z-axis and the rotation angle θ around the z-axis z are fixed, they are shown as points. The horizontal axis represents the values on the z-axis, and the vertical axis represents the rotation angle around the z-axis. The initial value may be defined in advance or specified in the design data or the like. Region 911 corresponds to the base material.

[0052] Figure 10 shows the adjustment process of the rotation angle θ around the x-axis based on the interference maps shown in Figures 9A to 9C. x Similar to Figure 7, interference determination is performed, and after adjusting to a rotation angle where no interference occurs, smoothing processing is performed. In the line 903, interference occurs between the torch 102 and the base material. In the line 904, it is adjusted so that no interference occurs. Furthermore, by performing smoothing processing such as the lines 905 and 906, it becomes possible to control the posture of the torch 102 so as not to cause a sudden change in the rotation angle.

[0053] In the example of Figure 10, without adjusting the posture parameters (y, θ y ) of the y-axis and the posture parameters (z, θ z ) of the z-axis, the posture parameters (x, θ of the x-axisx ) only is adjusted, the case where control parameters without interference can be obtained was shown. On the other hand, depending on the progress of the additive manufacturing, in the state where the attitude parameters of the y-axis and z-axis are fixed, there may be no rotation angle without interference around the x-axis. In such a case, by adjusting the values around the y-axis and z-axis simultaneously in parallel, interference may not occur in any axial direction.

[0054] [Processing Flow] FIG. 11 is a flowchart of the process related to the adjustment of the attitude parameters of the torch 102 according to the present embodiment. This processing flow is executed by the information processing apparatus 200. For example, it may be realized by a processing unit such as a CPU included in the information processing apparatus 200 reading a program for realizing each part shown in FIG. 1 from a storage unit (not shown) and executing it. Further, it is assumed that layer formation plan data for additive manufacturing is prepared before this processing flow is executed. Note that this processing flow may be executed in advance before the operation of additive manufacturing is started, or may be executed in parallel during the operation of additive manufacturing.

[0055] In S1101, the information processing apparatus 200 acquires shape information, torch information, and torch movement information from the layer formation plan data. The shape information includes information related to the shape of each path in addition to the final shape of the additive manufactured object. The shape information may be, for example, CAD information of the additive manufactured object including the base material sliced or divided. The shape information may include that which defines the layer formation of beads for each pass or that which predicts this. By including such information, it becomes possible to accurately predict the interference of the torch 102. Note that as a method for predicting the layer formation of beads, for example, the methods described in JP-A-2022-071692 and JP-A-2022-093023 may be used.

[0056] In addition, in the shape information, when the data representation format related to the laminated object includes irregular unevenness or the like, for example, the outer surface may be smoothed by interpolating the outer surface with a predetermined curved surface or curve model. The smoothing method is not particularly limited, and a known method may be used. The torch information may include, in addition to the information related to the shape of the torch 102 as shown in FIG. 2, the information on the possible postures of the torch 102. With the torch information, for example, a region R as shown in FIG. 4 can be specified. The torch movement information includes, for example, the initial values of the postures related to the formation corresponding to the line 903 shown in FIG. 9A. The initial values may be represented in the form of coordinates (x, y, z) of each axis and angles (θ x , θ y , θ z ) corresponding to the above posture parameters. Further, the torch movement information may include the movement path of the torch 102 when forming a bead, the movement path of the torch from the end position of one path to the start position of the next path, the lamination order of the paths, and the like.

[0057] In S1102, based on the shape information acquired in S1101, the information processing apparatus 200 focuses on one of the unprocessed paths. Usually, in the laminated manufacturing, since the order of the paths to be formed is defined in advance, the information processing apparatus 200 focuses on them in order according to the order.

[0058] In S1103, based on the various information acquired in S1101, the information processing apparatus 200 creates a plurality of interference maps corresponding to a plurality of axes and a plurality of paths. That is, an interference map as shown in FIG. 8 is created. As a method for creating the interference map here, for example, it may be generated by specifying the end coordinates of the base material or the formed bead as shown in FIG. 5 (for example, y in FIG. 5 B ). Alternatively, a three-dimensional shape model may be defined for the laminated object or the base material to create an interference map.

[0059] In S1104, the information processing apparatus 200 sets initial values for the x-axis, y-axis, and z-axis with respect to the interference map created in S1103. For example, as shown in FIGS. 9A to 9C, initial values of the rotation angle, which are attitude parameters for each axis, are set. The initial values of the attitude parameters may be defined by, for example, the stick operation information. As shown in FIGS. 9A to 9C, according to the movement path of the torch 102, two of the three axes may be fixed and one axis may be set to be changed.

[0060] In S1105, the information processing apparatus 200 performs an interference determination by comparing the interference map created in S1103 with the initial values set in S1104.

[0061] In S1106, the information processing apparatus 200 determines whether interference has occurred in at least a part of the three axes based on the result of the interference determination in S1105. If interference has occurred in at least a part (YES in S1106), the process of the information processing apparatus 200 proceeds to S1107. On the other hand, if no interference has occurred (NO in S1106), the process of the information processing apparatus 200 proceeds to S1119. In the interference determination here, if it is located on the interference boundary, it may be determined that interference occurs.

[0062] In S1107, the information processing apparatus 200 updates the stick operation information so that no interference occurs at the interference position indicated by the interference map. At this time, if interference can be avoided by changing the rotation angle around the same axis, the rotation angle is updated. If interference cannot be avoided by changing the rotation angle, the rotation angle around another axis is changed.

[0063] In S1108, the information processing apparatus 200 performs smoothing processing on the update result of S1107. For example, the smoothing processing is performed as shown in FIGS. 7 and 10. Note that when only the torch movement information of one axis is updated in S1107, the smoothing processing for that axis may be performed. On the other hand, when the torch movement information of two or more axes is updated in S1107, the smoothing processing may be performed for all of them. After that, the processing of the information processing apparatus 200 returns to S1105 and the interference determination is performed again. Note that if interference can be avoided in one process, the processing for the target path may be terminated and the process may proceed to S1109.

[0064] In S1109, the information processing apparatus 200 determines the torch movement information of the target path. That is, the posture parameters (x, θx) of the torch 102 with respect to the target path are determined.

[0065] In S1110, the information processing apparatus 200 determines whether there is an unprocessed path in the shape information. If there is an unprocessed path (YES in S1110), the processing of the information processing apparatus 200 returns to S1102 and the processing is repeated focusing on the next unprocessed path. On the other hand, if there is no unprocessed path (NO in S1110), the processing of the information processing apparatus 200 proceeds to S1111.

[0066] In S1111, the information processing apparatus 200 performs a shaping operation based on the shape information and the determined torch movement information. Then, this processing flow ends.

[0067] As described above, according to the present embodiment, it is possible to automatically adjust the posture parameters so as to avoid interference between the welding torch and the shaped object in layered manufacturing.

[0068] <Other Embodiments> In the above-described embodiment, as shown in FIG. 7, an example of a configuration for adjusting the entire path 1 (for example, line 400) was shown. However, the present invention is not limited to this, and a configuration in which some posture parameters are sampled and adjusted may also be used. More specifically, among a plurality of consecutive posture parameters included in line 400, posture parameters (x, θ x ) at predetermined intervals are targeted for adjustment, and smoothing processing may be performed using the results.

[0069] Further, in the present invention, a program or application for realizing the functions of the above-described one or more embodiments is supplied to a system or apparatus using a network or a storage medium or the like, and one or more processors in the computer of the system or apparatus read and execute the program. This processing can also realize the functions.

[0070] Moreover, it may be realized by a circuit (for example, ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array)) that realizes one or more functions.

[0071] As described above, the following matters are disclosed in this specification. (1) A control device (for example, 200) of a robot (for example, 100) that performs additive manufacturing using a welding torch (for example, 102), an acquisition means (for example, 204, 206) that acquires shape information of a workpiece, torch information of the welding torch, and torch movement information of the welding torch during the additive manufacturing, a generation means (for example, 207) that generates an interference map indicating position and posture parameters of the welding torch at which interference occurs between the workpiece and the welding torch based on the shape information and the torch information, a specifying means (for example, 207) that specifies a position at which interference occurs between the welding torch and the workpiece based on the interference map and the position and posture of the welding torch defined by the torch movement information, Adjusting means (e.g., 207) for adjusting the parameters of the posture of the welding torch at the position specified by the specific means and having the interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system, the specific means is a control device that specifies, as parameters to be corrected, the parameters of the posture at the position where interference occurs on any one of the plurality of axes.

[0072] According to this configuration, it becomes possible to automatically adjust the posture parameters so as to avoid interference between the welding torch and the shaped object in additive manufacturing.

[0073] (2) The control device according to (1), wherein the interference map associates an axis in a three-dimensional coordinate system with an angle around the axis, and defines a region where the shaped object is located.

[0074] According to this configuration, it becomes possible to perform interference determination with higher accuracy using an interference map corresponding to the posture parameters according to each axis.

[0075] (3) The control device according to (1) or (2), wherein the interference map is generated for each path when the shaped object is additively manufactured.

[0076] According to this configuration, it becomes possible to perform interference determination corresponding to the shape of the beads formed in sequence by additive manufacturing.

[0077] (4) The control device according to any one of (1) to (3), wherein the adjusting means adjusts the parameters by applying an offset to the parameters of the posture of the welding torch at the interfering position and performing a smoothing process on the parameters of the posture at continuous positions.

[0078] According to this configuration, it becomes possible to suppress a sudden change in the posture of the welding torch and perform smooth additive manufacturing.

[0079] (5) The control device further includes prediction means (e.g., 207) for predicting the shape of the object to be formed for each path of the additive manufacturing based on the shape information, wherein the generation means generates the interference map based on the shape of the object to be formed predicted by the prediction means, the control device according to any one of (1) to (4).

[0080] According to this configuration, it is possible to perform interference determination corresponding to the shape of the beads sequentially formed by additive manufacturing. In particular, even when there is no shape information for each pass, it is possible to predict the shape and perform interference determination.

[0081] (6) The prediction means further interpolates the outer surface of the shape of the object to be formed for each predicted path by a predetermined curved surface or curve model, the control device according to (5).

[0082] According to this configuration, even when a distorted shape or a discontinuous shape occurs in the prediction result, the shape can be stabilized and accurate interference determination can be performed.

[0083] (7) A control method for a robot (e.g., 100) that performs additive manufacturing using a welding torch (e.g., 102), an acquisition step (e.g., S1101) of acquiring shape information of the object to be formed, torch information of the welding torch, and torch movement information of the welding torch during the additive manufacturing, a generation step (e.g., S1103) of generating an interference map indicating a region where the object to be formed is located based on the shape information, a specifying step (e.g., S1105, S1106) of specifying a position where interference occurs between the welding torch and the object to be formed based on the interference map and the position and orientation of the welding torch defined by the torch information and the torch movement information, an adjustment step (e.g., S1107, S1108) of adjusting a parameter of the orientation of the welding torch at the position specified in the specifying step, and having, wherein the interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system, A control method for specifying, as parameters to be corrected, the parameters of the posture of the position where interference occurs at any one of the plurality of axes in the specific process.

[0084] According to this configuration, it becomes possible to automatically adjust the posture parameters so as to avoid interference between the welding torch and the formed object in layered manufacturing.

[0085] (8) A computer (for example, 200) is caused to perform an acquisition step (for example, S1101) of acquiring the shape information of the formed object, the torch information of the welding torch (for example, 102), and the torch movement information of the welding torch during layered manufacturing; a generation step (for example, S1103) of generating an interference map showing the region where the formed object is located based on the shape information; a specification step (for example, S1105, S1106) of specifying the position where interference occurs between the welding torch and the formed object based on the interference map and the position and posture of the welding torch defined by the torch information and the torch movement information; an adjustment step (for example, S1107, S1108) of adjusting the parameters of the posture of the welding torch at the position specified in the specification step; and the interference map is generated corresponding to each of the plurality of axes in a three-dimensional coordinate system, A program for specifying, as parameters to be corrected, the parameters of the posture of the position where interference occurs at any one of the plurality of axes in the specific process.

[0086] According to this configuration, it becomes possible to automatically adjust the posture parameters so as to avoid interference between the welding torch and the formed object in layered manufacturing.

Explanation of Reference Numerals

[0087] 1... Layered manufacturing system 100... Layered manufacturing apparatus 101... Shape sensor 102... Torch 103…Base 104…Welding robot 106…Robot controller 107…Power supply 108…Weld bead 200…Information processing device 201…Fabrication control unit 202…Power supply control unit 203…Feeding control unit 204…DB (Database) management unit 205…Shape data acquisition unit 206…Teaching data acquisition unit 207…Parameter adjustment unit 208…Peripheral device control unit W…Stacked fabricated object M…Filler material

Claims

1. A control device for a robot that performs additive manufacturing using a welding torch, comprising: an acquisition means for acquiring shape information of a workpiece, torch information of the welding torch, and torch movement information of the welding torch during the additive manufacturing; a generation means for generating an interference map showing parameters of the position and orientation of the welding torch at which interference occurs between the workpiece and the welding torch based on the shape information and the torch information; a specifying means for specifying a position where interference occurs between the welding torch and the workpiece based on the interference map and the position and orientation of the welding torch defined by the torch movement information; an adjustment means for adjusting parameters of the orientation of the welding torch at the position specified by the specifying means; and having the interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system, the specifying means specifies, as parameters to be corrected, parameters of the orientation of a position where interference occurs on any one of the plurality of axes, a control device.

2. The control device according to claim 1, wherein the interference map associates an axis in a three-dimensional coordinate system with an angle around the axis, and defines a region where interference occurs between the workpiece and the welding torch.

3. The control device according to claim 1, wherein the interference map is generated for each path when additive manufacturing the workpiece.

4. The control device according to claim 1, wherein the adjustment means adjusts the parameters by applying an offset to the parameters of the orientation of the welding torch at the interfering position and performing a smoothing process on the parameters of the orientation of consecutive positions.

5. further comprising a prediction means for predicting the shape of the workpiece for each path of the additive manufacturing based on the shape information, the generation means generates the interference map based on the shape of the workpiece predicted by the prediction means, the control device according to claim 1.

6. The control device according to claim 5, wherein the prediction means further interpolates an outer surface of the shape of the workpiece for each predicted path by a predetermined curved surface or curve model.

7. A control method for a robot that performs additive manufacturing using a welding torch, comprising: an acquisition step of acquiring shape information of a workpiece, torch information of the welding torch, and torch movement information of the welding torch during the additive manufacturing; A generation step of generating an interference map indicating parameters of the position and orientation of the welding torch at which interference occurs between the shaped object and the welding torch based on the shape information and the torch information; An identification step of identifying a position where interference occurs between the welding torch and the shaped object based on the interference map and the position and orientation of the welding torch defined by the torch movement information; An adjustment step of adjusting the parameter of the orientation of the welding torch at the position identified in the identification step; comprising: The interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system; In the identification step, a parameter of the orientation of a position where interference occurs in any one of the plurality of axes is identified as a parameter to be corrected. A control method.

8. On a computer, An acquisition step of acquiring shape information of a shaped object, torch information of a welding torch, and torch movement information of the welding torch during additive manufacturing; A generation step of generating an interference map indicating parameters of the position and orientation of the welding torch at which interference occurs between the shaped object and the welding torch based on the shape information and the torch information; An identification step of identifying a position where interference occurs between the welding torch and the shaped object based on the interference map and the position and orientation of the welding torch defined by the torch movement information; An adjustment step of adjusting the parameter of the orientation of the welding torch at the position identified in the identification step; causing to execute, The interference map is generated corresponding to each of a plurality of axes in a three-dimensional coordinate system; In the identification step, a parameter of the orientation of a position where interference occurs in any one of the plurality of axes is identified as a parameter to be corrected. A program.

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