Welding torch assembly with integrated vision system

Abstract

The present disclosure provides an apparatus for mounting a welding torch to a robotic arm, comprising a mounting body having a torch connector for holding the welding torch and an arm connector for coupling the mounting body to the robotic arm, and one or more cameras integrated into the mounting body, the one or more cameras configured to capture images of the active welding area at the bottom end of the welding torch from two or more angles to generate a three-dimensional view of the weld seam.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This patent application claims priority to U.S. Provisional Patent Application No. 63 / 384,720, filed November 22, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to robotic welding systems. [Background technology]

[0003] Various types of welding systems use cameras and other sensors to control and / or monitor the robotic welding operation. Many existing vision-based solutions used to monitor the operation of robotic welding systems are not suitable for use in situations where clearance around the welding torch is limited.

[0004] Examples of prior art vision-based systems used in welding operations include US Pat. No. 6,223,999, as well as US Pat. Nos. 5,529,999 and 5,669,233. The present inventors have recognized a need for improved apparatus and methods for capturing images (both still and video) of welding operations. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Korean Patent No. 1020050068079 [Patent Document 2] Chinese Utility Model No. 205614171 [Patent Document 3] Chinese Utility Model No. 213560726 Summary of the Invention [Means for solving the problem]

[0006] One aspect of the present disclosure provides an apparatus for mounting a welding torch on a robotic arm, the apparatus comprising: a mounting body having a torch connector for holding the welding torch and an arm connector for coupling the mounting body to the robotic arm; and one or more cameras integrated into the mounting body and configured to capture images of the active welding area at the bottom end of the welding torch from two or more angles to generate a three-dimensional view of the weld seam.

[0007] Another aspect of the present disclosure provides a welding torch assembly including a welding torch; a mounting body coupled to the welding torch, the mounting body having an arm connector for coupling the mounting body to a robotic arm; and one or more cameras integrated into the mounting body and configured to capture images of an active welding area at a lower end of the welding torch from two or more angles to generate a three-dimensional view of the weld seam.

[0008] Further aspects of the disclosure and details of exemplary embodiments are set forth below. The following figures illustrate embodiments in which like reference numerals indicate like parts: The embodiments are illustrated in the accompanying figures by way of example and not by way of limitation. [Brief explanation of the drawings]

[0009] [Figure 1] 1 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to one aspect of the present disclosure. [Figure 1A] 2 illustrates the mounting structure of FIG. 1 attached to a robotic arm, according to one embodiment of the present disclosure. [Figure 1B] 2 shows the mounting structure of FIG. 1 holding a linear welding torch; [Figure 2] 10 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to another aspect of the present disclosure. [Figure 2A] 3 shows the mounting structure of FIG. 2 holding a linear welding torch. [Figure 3]10 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to another aspect of the present disclosure. [Figure 3A] 4 shows the mounting structure of FIG. 3 holding a linear welding torch. [Figure 4] 10 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to another aspect of the present disclosure. [Figure 4A] 5 shows the mounting structure of FIG. 4 holding a linear welding torch. [Figure 5] 10 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to another aspect of the present disclosure. [Figure 5A] 6 illustrates the mounting structure of FIG. 5 attached to a robotic arm according to one embodiment of the present disclosure. [Figure 6] 10 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to another aspect of the present disclosure. [Figure 7] 10 illustrates a mounting structure with an integrated camera for coupling a welding torch to a robotic arm according to another aspect of the present disclosure. [Figure 7A] 8 shows the mounting structure of FIG. 7 holding a linear welding torch. DETAILED DESCRIPTION OF THE INVENTION

[0010] Described below is an exemplary welding torch assembly including an integrated camera system configured to capture images (both still and video) of the active welding area at the lower end of the welding torch from two or more angles to generate a three-dimensional view of the weld seam at the weld point. Some embodiments include a mounting structure with multiple integrated cameras for coupling the welding torch to a robotic arm, allowing use with a wide variety of existing welding torches and robotic arms. As used herein, the term "robotic arm" refers to all types of mechanical manipulators. Images from the camera system are provided to an image processing system, such as the NovEye™ system from Novarc Technologies Inc., and used to control the operation of the welding torch and the movement of the robotic arm. Examples of images from cameras positioned to capture images of the welding operation are disclosed, for example, in PCT Publication Nos. WO 2019153090 and WO 2022126274, both of Novarc Technologies Inc., which are hereby incorporated by reference herein. The welding torch assemblies and mounting structures disclosed herein with integrated vision systems can be attached to any type of welding robot and mechanical arm.

[0011] For brevity and clarity of the figures, reference numbers may be repeated among the figures to indicate corresponding or similar elements. Numerous details have been described to provide an understanding of the examples described herein. These examples may be practiced without these details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the described examples. This description should not be construed as limiting the scope of the examples described herein.

[0012] FIG. 1 illustrates an exemplary apparatus 100 for mounting a welding torch to a robotic arm according to one embodiment of the present disclosure. The apparatus 100 includes a mounting body 102 having an arm connector 104 for connecting to the end of a robotic arm. In some embodiments, the arm connector 104 may include a mounting flange with four bolts and a locator pin (not shown) for connecting to several types of robotic arms, although the configuration of the arm connector 104 will depend on the configuration and brand of the robotic arm. While FIG. 1A illustrates the apparatus 100 of FIG. 1 mounted to an exemplary six-axis robotic arm, it should be understood that the apparatus 100 can be mounted to any type of robotic manipulator.

[0013] The mounting body 102 incorporates multiple cameras 110 (three in the illustrated example) oriented to capture images of the weld spot P from different angles. In the illustrated example, three cameras 110 are positioned within the body such that their optical axes 110A, 110B, 110C are focused on the welding zone Z to capture images of the weld seam as it is being formed. Images from the cameras 110 are provided to an image processing system for seam tracking, distance control, and / or control of welding parameters of the welding operation. By capturing real-time images of the weld pool from different angles, the image processing system can generate a three-dimensional view showing the size and shape of the weld pool and its position relative to the weld seam during the welding operation.

[0014] 1, mounting body 102 comprises an elongated body having a first end 106 and a second end 108, and torch T is configured to be held by torch bracket 107 connected to first end 106 of body 102. Camera 110 is positioned within an enclosure within body 102 near second end 108 and is covered by window 112 formed of one or more transparent or partially transparent layers, such as, for example, an auto-darkening filter, a heat shield, blackout glass, or other suitable material.

[0015] 1, device 100 is shown holding an angled or "gooseneck" style welding torch T, but it should be understood that device 100 can be configured to hold other types of welding torches by adjusting the angle of camera 110. For example, FIG. 1B shows device 100 holding a straight welding torch T'.

[0016] FIG. 2 illustrates an exemplary apparatus 200 for mounting a welding torch to a robotic arm according to another embodiment of the present disclosure. The apparatus 200 is similar in some respects to the apparatus 100 of FIG. 1 in that the apparatus 200 includes an elongated mounting body 202 having an arm connector 204 and first and second ends 206, 208, with a camera 210 positioned within an enclosure within the body 202 near the second end 208 and covered by a window 212. In the embodiment of FIG. 2, the apparatus 200 includes a weave motor 214 mounted to the body 202, a rotating element 216 extending from the first end 206 of the body 202, and a torch bracket 207 connected to the rotating element 216, such that activation of the weave motor 214 can move the torch T back and forth in a weaving motion during a welding operation (e.g., when welding a seam with a relatively wide gap). The camera 210 moves with the torch T as it is moved by the robotic arm or other actuator, but is isolated from the weaving motion imparted by the weave motor 214 so that the camera 210 remains focused on the seam.

[0017] 2, device 200 is shown holding an angled or "gooseneck" style welding torch T, but it should be understood that device 200 can be configured to hold other types of welding torches by adjusting the angle of camera 210. For example, FIG. 2A shows device 200 holding a straight welding torch T'.

[0018] FIG. 3 illustrates an exemplary apparatus 300 for mounting a welding torch on a robotic arm according to another embodiment of the present disclosure. Apparatus 300 is similar in some respects to apparatus 100 of FIG. 1 and apparatus 200 of FIG. 2 in that apparatus 300 includes an elongated mounting body 302 having an arm connector 304 and first and second ends 306 and 308, with cameras 310 (two in the illustrated embodiment) positioned within an enclosure within body 302. Apparatus 300 includes a torch bracket 307 connected to a mounting element 315 extending from first end 306 of body 302. In the embodiment of FIG. 3, body 302 occupies a smaller volume, particularly at second end 308, and camera 310 is positioned in a central portion of body 302 and points toward mirror 311 near second end 308. Mirror 311 is positioned next to window 312 and oriented to reflect an image from the welding zone to camera 310. In some embodiments, a single camera can be used instead of two cameras 310, where the single camera is pointed at multiple mirrors configured to reflect images of the welding zone from different angles back to the single camera.

[0019] 3, device 300 is shown holding an angled or "gooseneck" style welding torch T, but it should be understood that device 300 can be configured to hold other types of welding torches by adjusting the angle of camera 310. For example, FIG. 3A shows device 300 holding a straight welding torch T'.

[0020] Figure 4 illustrates an exemplary apparatus 400 for mounting a welding torch on a robotic arm according to another embodiment of the present disclosure. The apparatus 400 is similar in some respects to the apparatus 100 of Figure 1 and the apparatus 200 of Figure 2, in that the apparatus 400 includes an elongated mount body 402 having an arm connector 404 and first and second ends 406 and 308, with cameras 410 (three in the illustrated embodiment) positioned within an enclosure within the body 402 near the second end 408 and covered by a window 412. The apparatus 400 further includes a torch bracket 407 having three protrusions 409 extending outwardly therefrom, and three additional cameras 410 positioned within the protrusions 409 to capture images of the torch T from all directions.

[0021] 4, device 400 is shown holding an angled or "gooseneck" style welding torch T, but it should be understood that device 400 can be configured to hold other types of welding torches by adjusting the angle of camera 410. For example, FIG. 4A shows device 400 holding a straight welding torch T'.

[0022] FIG. 5 illustrates an exemplary apparatus 500 for mounting a welding torch to a robot arm in accordance with another embodiment of the present disclosure. In the embodiment of FIG. 5, the apparatus 500 includes a flange-like mounting body 502 extending radially outward from the periphery of the upper end of a linear welding torch T'. The mounting body 502 includes an arm connector 504 for connecting to the robot arm. In some embodiments, the arm connector 504 may include a mounting flange with four bolts and a locator pin (not shown) for connecting to several types of robot arms, although the configuration of the arm connector 504 will depend on the brand of the robot arm. Multiple cameras 510 are mounted to the flange of the mounting body 502 and oriented to capture images of the welding zone from multiple angles. In the illustrated example, the apparatus 500 includes three cameras 510 evenly spaced around the flange. In other embodiments, a different number of cameras 510 can be positioned on the flange, and the cameras may or may not be evenly spaced around the flange. FIG. 5A illustrates the apparatus 500 of FIG. 5 mounted to a robot arm in accordance with one aspect of the present disclosure.

[0023] FIG. 6 illustrates an exemplary apparatus 600 for mounting a welding torch to a robotic arm according to another embodiment of the present disclosure. In the embodiment of FIG. 6, the apparatus 600 includes a curved, elongated body 602 having a first end 606 and a second end 608 angled downward from a central portion 605. The central portion 605 of the mounting body 602 is coupled to an arm connector 604 by a shaft 603. The length of the shaft 603 can be selected to provide a desired clearance between the torch T and a robotic arm (not shown) connected to the arm connector 604. A torch bracket 607 is positioned at the first end 606 of the mounting body 602, and multiple cameras 610 are attached to the second end 608 of the mounting body 602.

[0024] In the exemplary embodiment of Figures 1-4 and 6, the mounting body comprises an elongated body elongated along a first direction, and the torch connector is configured to hold the welding torch in an orientation along a second direction generally perpendicular to the first direction. In other embodiments, the apparatus may be configured to hold the welding torch in a different orientation depending on the spatial constraints of the desired welding operation. For example, Figure 7 illustrates an exemplary apparatus 700 for mounting a welding torch to a robot arm according to another embodiment of the present disclosure, configured to hold the welding torch T in an orientation generally parallel to the orientation of the elongated mounting body 702. In the example of Figure 7, an arm connector 704 is connected to a first end 706 of the elongated mounting body 702, and a camera assembly 710 is positioned within the elongated mounting body 702 near the second end 708. The camera assembly 710 includes an angled optical head with one or more lenses oriented to focus their optical axes on the welding zone and one or more mirrors oriented to direct light from the lenses at a generally perpendicular angle (e.g., at an angle of about 70 degrees to about 110 degrees) toward one or more filters and light-sensitive sensors located near the center of the elongated mounting body 702. Although only one camera assembly 710 is shown in the illustrated example, the apparatus 700 of FIG. 7 can accommodate two, three, or more camera assemblies within the elongated mounting body 702. 7, apparatus 700 includes a weave motor 714 mounted within body 702 and a rotating element 716 extending from the side of body 702 near its first end 706, and a torch bracket 707 connected to the rotating element 716, such that activation of weave motor 714 causes torch T to move back and forth in a weaving motion during a welding operation (e.g., when welding a seam across a relatively wide gap). Camera assembly 710 moves with torch T as it is moved by a robotic arm or other actuator, but is isolated from the weaving motion imparted by weave motor 714 so that the camera remains focused on the seam.

[0025] 7, device 700 is depicted as holding an angled or "gooseneck" style welding torch T, however, it should be understood that device 700 can be configured to hold other types of welding torches by adjusting the angle of the optical head of camera assembly 710. For example, FIG. 7A shows device 700 holding a straight welding torch T'.

[0026] In some implementations of the embodiments described above with reference to Figures 1-7, at least one of the cameras 110 / 210 / 310 / 410 / 510 / 610 / 710 includes an integrated lighting system including one or more light emitting elements disposed around the periphery of the at least one camera lens. In some implementations, the devices 100 / 200 / 300 / 400 / 500 / 600 / 700 of the embodiments described above with reference to Figures 1-7 are connected to a source of compressed air or other cooling fluid and configured to direct the cooling fluid toward the camera 110 / 210 / 310 / 410 / 510 / 610 / 710. The cooling fluid may also be used to keep the camera clean and free of smoke, welding debris, dust, or other debris. For example, in some embodiments, an air blade or similar air direction assembly is coupled to the device 100 / 200 / 300 / 400 / 500 / 600 / 700 and configured to direct forced air towards the camera 110 / 210 / 310 / 410 / 510 / 610 / 710 to cool and / or clean the camera.

[0027] As those skilled in the art will appreciate in light of the above disclosure, by providing one or more cameras configured to capture real-time images of the welding operation, apparatuses according to some embodiments of the present disclosure facilitate real-time, adaptive control of welding. The cameras visualize the real-time status of the weld puddle (or "weld pool"), the geometry of the weld under the arc, the torch, the wire, the tack weld, the root opening, the elevation difference, the gap, and other visual parameters important to the welding operator. In embodiments with at least two cameras (or a single camera configured with optics for capturing images from different angles), the apparatus of the present disclosure enables capture of stereo vision images including depth information, eliminating sensitivity to camera tilt relative to the welding direction. The depth information provides the ability to generate a three-dimensional view of the weld characteristics, significantly improving visual perception for real-time, adaptive control of the weld. Furthermore, in embodiments with three or more cameras configured to capture images 360 degrees around the welding torch, the apparatus of the present disclosure enables an image processing system to generate a bird's-eye view of the welding operation. The bird's-eye view can be configured to maintain a weld view independent of local movement and / or rotation of the torch during welding. Additionally, in certain preferred embodiments of the present disclosure (regardless of the number and configuration of cameras), the device is configured to generate time-stamped images of the welding operation to facilitate pre- and post-weld inspection as well as weld control.

[0028] Embodiments of the systems and methods described herein may be implemented in a combination of hardware and software. These embodiments may be implemented on programmable computers, each computer including at least one processor, a data storage system (including volatile or non-volatile memory or other data storage elements, or a combination thereof), and at least one communication interface. For example, the programmable computer may be a server, a network appliance, an on-board controller for a connected or autonomous vehicle, a set-top box, an embedded device, a computer expansion module, a personal computer, a laptop, a personal data assistant, a cloud computing system, or a mobile device. A cloud computing system is operable to provide computing services through shared resources, software, and data over a network.

[0029] Program code is applied to input data to perform the functions described herein and to generate output information. The output information is applied to one or more output devices. In some embodiments, the communication interface may be a network communication interface. In embodiments where elements may be combined, the communication interface may be a software communication interface, such as for inter-process communication. In still other embodiments, there may be a combination of communication interfaces implemented as hardware, software, or a combination thereof.

[0030] Each program may be implemented in a high-level procedural language, an object-oriented programming language, or a scripting language, or both, to communicate with a computer system. However, the programs may alternatively be implemented in assembly or machine language, if desired. In either case, the language may be a compiled or interpreted language. Each such computer program is stored on a general- or special-purpose programmable computer-readable storage medium or device (e.g., ROM or magnetic disk) and is used to configure and operate the computer when the storage medium or device is read by the computer to perform the procedures described herein. Embodiments of the present system may also be considered to be implemented as a non-transitory computer-readable storage medium configured with a computer program, the storage medium so configured causing the computer to operate in a specific, predefined manner to perform the functions described herein.

[0031] Furthermore, the systems, processes, and methods of the described embodiments can be distributed as a computer program product that includes a physical, non-transitory, computer-readable medium that stores computer-usable instructions for one or more processors. The medium can be provided in various forms, including one or more floppy disks, compact disks, tapes, chips, magnetic and electronic storage media, etc. The computer-usable instructions can be provided in various forms, including compiled and non-compiled code.

[0032] The embodiments described herein may be relevant to various types of computing applications, such as image processing and generation applications, computing resource related applications, speech recognition applications, video processing applications, semiconductor manufacturing, etc. As an illustrative example, embodiments may be described herein in the context of image related applications.

[0033] It will be appreciated that numerous specific details have been set forth to provide a thorough understanding of the exemplary embodiments described herein. However, those skilled in the art will understand that the embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the embodiments described herein. Furthermore, this description should not be construed as in any way limiting the scope of the embodiments described herein, but merely as describing implementations of various exemplary embodiments described herein.

[0034] This description provides many exemplary embodiments of the inventive subject matter. While each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus, if one embodiment includes elements A, B, and C and a second embodiment includes elements B and D, the inventive subject matter is considered to include any other remaining combinations of A, B, C, or D, even if not explicitly disclosed.

[0035] As will be apparent to those skilled in the art in light of the above disclosure, many variations and modifications are possible to the methods and systems described herein. While numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain modifications, permutations, additions, and subcombinations thereof. Accordingly, the following appended claims and any claims introduced later are intended to be construed to include all modifications, permutations, additions, and subcombinations that could reasonably be inferred by one skilled in the art. The scope of the claims is not intended to be limited to the embodiments described in the examples, but rather is to be accorded the broadest interpretation consistent with the above disclosure.

[0036] The present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are considered in all respects to be illustrative and not restrictive.

Claims

1. 1. An apparatus for attaching a welding torch to a robotic arm, comprising: a mounting body having a torch connector for holding the welding torch and an arm connector for connecting the mounting body to the robot arm; one or more cameras integrated into the mounting body configured to capture images of the active welding area at the lower end of the welding torch from two or more angles to generate a three-dimensional view showing the size and shape of the weld pool and the position of the weld pool relative to the weld seam during the welding operation; An apparatus comprising:

2. 2. The apparatus of claim 1, wherein the mounting body comprises an elongated body having a first end and a second end, the torch connector being at the second end of the body, and the one or more cameras being mounted near the first end of the body.

3. 3. The apparatus of claim 2, wherein the one or more cameras are mounted within an enclosure within the body and configured to capture images of the active welding area through a window formed in the body near the first end.

4. The apparatus of claim 3 , wherein the one or more cameras comprise at least two cameras oriented to point directly through the window.

5. 4. The apparatus of claim 3, wherein the one or more cameras comprise at least two cameras positioned adjacent the window and oriented to point toward a mirror configured to reflect an image of the active welding area.

6. 4. The apparatus of claim 3, wherein the one or more cameras comprise a single camera positioned next to the window and oriented to point toward at least two mirrors configured to reflect images of the active welding area from different angles.

7. 7. The apparatus of claim 2, further comprising a weave actuator connected between the body and the torch connector, the weave actuator configured to rotate the torch connector relative to the body such that the welding torch is controllable to perform the weaving motion without the one or more cameras moving in the weaving motion.

8. The apparatus of any one of claims 2 to 7, wherein the torch connector is configured to hold the welding torch in an orientation generally perpendicular to an orientation of the elongated body.

9. The apparatus of any one of claims 2 to 7, wherein the torch connector is configured to hold the welding torch in an orientation generally parallel to an orientation of the elongated body.

10. The apparatus of any one of claims 1 to 9, wherein the torch connector comprises a torch bracket extending around the torch, and the apparatus further comprises a plurality of additional cameras mounted to the torch bracket.

11. The apparatus of claim 10 , wherein the torch bracket includes a plurality of protrusions extending therefrom, and the additional cameras are mounted to the protrusions.

12. 10. The apparatus of claim 1, wherein the mounting body comprises a flange extending radially outwardly around an upper end of the welding torch, and the one or more cameras comprise a plurality of cameras mounted to the flange.

13. 13. The apparatus of any one of claims 1 to 12, wherein the one or more cameras comprise at least three cameras positioned to collectively capture images 360 degrees around the welding torch to generate a bird's-eye view of the welding operation.

14. 14. Apparatus according to any one of the preceding claims, wherein the at least one camera comprises an integrated lighting system comprising one or more light emitting elements arranged around a lens of the at least one camera.

15. 1. A welding torch assembly comprising: A welding torch, a mounting body connected to the welding torch, the mounting body having an arm connector for coupling the mounting body to a robot arm; one or more cameras integrated into the mounting body configured to capture images of the active welding area at the lower end of the welding torch from two or more angles to generate a three-dimensional view showing the size and shape of the weld pool and the position of the weld pool relative to the weld seam during the welding operation; A welding torch assembly comprising:

16. The welding torch assembly of claim 15 , wherein the mounting body is removably connected to the welding torch.

17. The welding torch assembly of claim 15 , wherein the mounting body is integral with the welding torch.

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