This present invention relates generally to systems and method for automated stud placement and welding, and in particular to robotically-controlled stud welders with the capability to identify one or more desired welding sites on a surface of a beam or girder and automatically weld studs at these sites, and related methods therefor.
Currently, each of the steps of grinding of desired weld location on an I-beam, placement of ceramic ferrules that are used to contain the weld pool during the welding process on the ground welding locations, placement of studs within the ferrules, welding of the studs to the I-beam, and then fracturing of the ferrules after the welding step is done manually by an individual walking along the length of the I-beam with or without an appropriate tool. Each of these steps is labor-intensive, time-consuming, and repetitive, and accordingly these steps drive up the costs of construction projects while leading to many worker injuries.
Accordingly, it is desirable to automate all or portions of the process noted above.
The invention is best understood from the following detailed description when read in connection with the accompanying figures. According to common practice, the various features of the invention shown in the figures may not be to scale. On the contrary, for purposes of clarity, the dimensions of the various features of the invention shown in the figures may be arbitrarily expanded or reduced. The systems and methods of the present application are further described with reference to the accompanying drawings, in which:
The ensuing detailed description provides preferred exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the herein disclosed inventions. Rather, the ensuing detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments in accordance with the herein disclosed invention. It is understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention, as set forth in the appended claims.
To aid in describing the invention, directional terms may be used in the specification and claims to describe portions of the present invention (e.g., upper, lower, left, right, etc.). These directional definitions are merely intended to assist in describing and claiming the invention and are not intended to limit the invention in any way. In addition, reference numerals that are introduced in the specification in association with a drawing figure may be repeated in one or more subsequent figures without additional description in the specification, in order to provide context for other features.
For purposes of the attached specification and claims, the terms “in data communication” and “in electrical communication” have the meaning that components are able to transmit signals, stimuli, or data either unidirectionally or bidirectionally between them.
For purposes of the attached specification and claims, the term “electronic command signal” has the meaning of a signal that is either transmitted or received by an electrical software or hardware component resulting in some resulting action, as would be appreciated by a person of ordinary skill in the fields of electronic engineering, electrical engineering, and software engineering.
In the embodiment shown in
The I-beam 2001 has a longitudinal axis 2002, a vertical height 2003, and a top surface 2005 having a width 2004. On the top surface 2005 of the I-beam 2001, a number of ground welding sites 2007 have been produced, and welded studs 2006 have already been welded to some of the ground welding sites 2007. As would be understood by a person having ordinary skill in the relevant art, ferrules will be used on top of the ground welding sites 2007 in order to encapsulate the molten weld pools during the arc welding process. For convenience, these ferrules are omitted from view in
As noted above, during operation the welding system 2010 of this embodiment moves alongside and parallel to the longitudinal axis 2002 of the I-beam 2001. In this embodiment, a positionable carriage 2022 comprising a Y-axis movement system 2033, an X-axis movement system 2069, and a Z-axis movement system 2081 is used to physically locate a stud placement and welding assembly 2170 above the top surface 2005 of the I-beam 2001 so that studs can be individually welded to respective ground welding sites 2007. In order to protect the components of the positionable carriage 2022 while on a job site and to reduce ambient light from interfering with the determination of the location of the ground welding sites 2007, an enclosure 2024 comprising a plurality of support beams (shown but not individually labeled in
In this embodiment, the welding system 2010 further comprises a control station assembly 2140 including movement controls (not labeled) for the positionable carriage 2022, welding controls (not labeled) for the stud placement and welding assembly 2170, and a display 2656 that provides a visual display of the field of view 2286 of the imager 2282a. As discussed below, the display 2656 can be used to display additional features of the invention. In this embodiment, the welding system 2010 further comprises a GPS antenna 2585 supported from the control station assembly 2140. With reference to the schematic diagram of
GPS receiver 2589 may be further adapted to use other positioning systems to accurately locate the position of GPS antenna 2585, such as a local based pseudo-GPS system, which may be further employed if satellite GPS signals are not available as might be experienced, for example, in an enclosed structure such as a building. GPS antenna 2585 may alternatively be mounted to the positionable carriage 2022. Any other position on welding system 2010, including the position of the stud placement and welding assembly 2170, may be determined by correcting for positional offsets from GPS antenna 2585 to the particular component position location. GPS receiver 2589 communicates with computer 2595 (discussed below) via communication channel (local bus cable) 2591. In an alternate embodiment, a second GPS antenna (not shown) and a second GPS receiver could be included as part of the welding system 2010 and used to determine the location of the stud placement and welding assembly 2170.
GPS antennas and cooperating receivers are offered by a number of manufactures including Trimble Navigation, Ltd. of Sunnyvale, Calif., Topcon Positioning Systems, Inc. of Livermore, Calif., and Leica Geosystems, Inc. of Norcross, Ga. Other GPS and non-GPS based systems are offered for determining the geographical position of objects and include for example LIDAR (light distance and ranging) systems (using triangulation), and are well known in the art of surveying. For example, a modern day “total solution” represents a complete electronic surveying tool incorporating one or more electronic theodolites along with accurate LIDAR systems to accurately determine the position of objects, and can precisely locate an object using for example known triangulation techniques. Any of these or other known location-determining devices could be employed, either in place of or in combination with GPS antenna 2585 and GPS receiver 2589, to permit the welding system 2010 to determine its location and the location of its various components with high accuracy.
As will be discussed below in detail, the welding system 2010 could be employed in a number of different methods of automating all or portions of the stud placement and welding process, including automated grinding of the top surface 2005 of the I-beam 2001 at desired weld site location(s) and automated ferrule placement and fracturing. In some of these methods, the GPS-enabled features are employed so that the welding system 2010 is aware of its position—and the position of each of its relevant components, e.g., the stud placement and welding assembly 2170—relative to the I-beam 2001.
Referring back to
Computer 2595 communicates with imager 2282a via local bus 2573, GPS receiver 2589 communicates with computer via local bus 2591, control station assembly 2140 communicates with computer 2595 via local bus 2632, the X-axis movement system 2069, Y-axis movement system 2033, and Z-axis movement system 2081 of the positionable carriage 2022 communicate with computer 2595 via local bus 2562, and the right hydrostatic drive 2320 and left hydrostatic drive 2325 are connected to the computer 2595 via local bus 2672. In this embodiment, all local busses 2573, 2591, 2632, 2562 and 2672 are grouped together and become part of main communication bus 2670, and all components connected to main communication bus 2670 are in bi-directional communication with each other. In
The hydrostatic drives 2320, 2325 are connected to the control station assembly 2140 via local bus 2633. Control station assembly 2140 is connected to the X-axis movement system 2069, Y-axis movement system 2033, and Z-axis movement system 2081 of the positionable carriage 2022 via local bus 2142 and to the stud placement and welding assembly 2170 via local bus 2172. In addition, the X-axis movement system 2069, Y-axis movement system 2033, and Z-axis movement system 2081 of the positionable carriage 2022 are connected to the stud placement and welding assembly 2170 via local bus 2174.
Referring now to
Program memory 2710 comprises machine vision acquisition and analysis program 2752 that controls the acquisition of images from imager 2282a. Control signals are sent to imager 2282a by program 2752 and include image trigger signal (i.e., when to acquire a raw image) and an electronic shutter signal (i.e., for how long should the image be acquired). Program 2752 also includes the camera calibration algorithm which corrects the raw image data input from imager 2282a for lens 2284a distortion and other non-ideal camera and image parameters. When an image is triggered, program 2752 then stores the calibrated image data to data memory 2720.
For some methods according to the present invention, program 2752 also analyzes the stored image captured by imager 2282a and identifies each ground welding site 2007 (or each grind/weld-location marking, as further discussed below) within the captured image using conventional image segmentation and other known image analysis algorithms. Such algorithms include image thresholding algorithms where ground welding sites 2007 are identified using the difference in grayscale values between the bright reflective welding site and the dull non-reflecting beam surface, as is well known in the art of image processing and analysis. Character recognition algorithms, which are well known in the art of image processing and analysis, may be used to determine weld locations where grind/weld-location marking(s)—e.g., “X”s—are provided on the top surface 2005 of the I-beam 2001 instead of ground welding sites 2007.
For some methods according to the present invention, program 2752 further identifies the center of each welding site (which may include the center of a manually placed ferrule), calculates the convention (u-v) pixel coordinates of the center of each non-repeated identified welding site, calculates the X-Y positions of the center of each non-repeated welding site, identifies the location of the beam edges of I-beam 2001, determines the respective u coordinates for the line images of beam edges, determines the number of pixels between the line images of the beam edges of I-beam 2001 using the line image u coordinates, and calculates the image pixel distance to object distance ratio from the beam edges of I-beam 2001 using beam width input data in addition to other image analysis and processing functions. Data including the (u,v) pixel coordinates of the center of every identified welding site and the X-Y coordinates for each welding site, along with the calculated pixel to object distance ratio is stored in data memory 2720, in addition to other data. Program 2752 also computes, using the camera calibration algorithm, the camera calibration parameters which are used to correct the raw image for lens distortion and stores these parameters in data memory 2720.
Program memory 2710 further comprises X-Y-Z systems positioning and control system program 2754. Program 2754 is used for controlling the position of the X-axis movement system 2069, Y-axis movement system 2033, and Z-axis movement system 2081 so that the stud placement and welding assembly 2170 can be brought into the correct locations for welding studs to the top surface 2005 of the I-beam 2001. Program memory 2710 further comprises welding control circuit program 2756, which interfaces with the welding controller circuit 2652 and controls the stud arc-welding process that is performed by the stud placement and welding assembly 2170. Program memory 2710 may also comprise other programs 2762, for example a program for performing location offset calculations to calculate weld site locations on an I-beam 2001 based on received location data from a location-identifying device (e.g., a GPS device), as discussed in further detail below with respect to the method shown in
Program memory 2710 further comprises GPS based control and positioning program 2758, which acts to input the welding site GPS location coordinates from a USB memory stick connected to computer 2595 or receives the welding site GPS location coordinates via other available communication ports previously disclosed (for example, through internet, Bluetooth, or WiFi connectivity), and stores these coordinates in data memory 2720. Additionally, the welding site coordinates could also be directly entered via a data-input means, such as a keyboard that is connected to the computer 2595. Thus, it should be understood that the welding site GPS coordinates may be used exclusively for forming the welding site coordinates contained in data memory 2720, or may be used in combination with the welding site coordinates determined using machine vision, either coordinate sets being transformed by program 2758 to be compatible with each other and other programs and systems. Program 2758 further compares the GPS position of the stud placement and welding assembly 2170 with previously-stored welding site GPS coordinates, and moves the stud placement and welding assembly 2170 to each set of desired welding site GPS coordinates via X-Y-Z systems positioning and control system program 2754 and the X-axis movement system 2069, Y-axis movement system 2033, and Z-axis movement system 2081 of the positionable carriage 2022.
Additionally, as further detailed below, the GPS coordinates of the location of I-beam 2001 (for example, the location of its side edges) and characteristics of the I-beam 2001 such as the length of its longitudinal axis 2002 and width 2004 may be inputted via a keyboard or by other means (such as USB or wireless connection) into computer 2595 and used by program 2758 to construct a welding path for welding system 2010 to follow. Other positional data may be entered into the computer 2595 to indicate “no welding” areas on the top surface 2005 of the I-beam 2001.
Program memory further includes GPS indexing program 2760, which may be used to automatically move the stud placement and welding assembly 2170 in a predefined pattern according to pre-programmed GPS positions and, in combination with other automated functionality of the welding system 2010, is able to weld studs at welding sites defined by an indexed position. Thus, as further detailed below, GPS indexing program 2760 allows for both the placement and welding of studs at pre-defined positions on the top surface 2005 of I-beam 2001.
In the present embodiment of the welding system 2010, once the imager 2282a has made a determination (if applicable) of where the ground welding sites 2007 are located on the top surface 2005 of the I-beam 2001, this information is used to communicate to the stud placement and welding assembly 2170 precisely where studs should be welded onto the top surface 2005 of the I-beam 2001. In this embodiment, a stud feeding assembly 2100 is used to feed studs to the stud placement and welding assembly 2170 so that the studs may be welded onto the I-beam 2001. Employing the principles discussed above in detail, the location of the stud placement and welding assembly 2170 within the positionable carriage 2022 with respect to the frame 2014 and the I-beam 2001 will be stored in computer 2595, and this information will be used to make the appropriate calculations and communicate how the stud placement and welding assembly 2170 is to be moved, via control of the X-axis movement system 2069, Y-axis movement system 2033, and Z-axis movement system 2081, in order to bring the stud placement and welding assembly 2170 and enclosed studs into the correct locations on the top surface 2005 of the I-beam 2001.
As noted above, the present invention comprises various methods of using the welding system 2010 to automate all or portions of the beam grinding, ferrule placement, and stud placement and welding operations that are currently performed manually.
In some methods according to the present invention, the operator may choose to pre-determine the GPS location of the welding sites 2008 without using the welding system 2010 discussed above. Referring now to
In this embodiment, also attached to pole 7010 is a visual level 7050 which gives an indication to the operator when pole 7010 is vertically placed over welding site 2008 on the surface 2005 of the I-beam 2001. Level 7050 may be, for example, model number 5198-054 manufactured by SECO. In this embodiment, also attached to pole 7010 is a manually-operated trigger switch 7060 and the computer 7070. The computer 7070 includes image acquisition software 7076. In this embodiment, computer 7070 is a fully functional computer having a RTOS or other commonly available operating system, for example Windows.
Additionally, in this embodiment the computer 7070 has communication ports (not shown) which allow for the attachment of computer peripherals. These communication ports may include for example USB, Wi-Fi, Bluetooth, and internet connectivity. For example, Wi-Fi signals—which are represented by radio waves 7082 and 7084—are being respectively received by and transmitted from an antenna 7090 that is in electrical communication with computer 7070 via electrical cable 7095. In this embodiment, antenna 7090 is operably configured to transmit and receive Wi-Fi signals.
A switch 7060 is in electrical communication with computer 7070 via wires 7061 and 7062. Further attached to pole 7010 is a calibrated imager 7105 having a lens 7110. Imager 7105 and lens 7110 are similar to imager 2282a and lens 2284a respectively, which are discussed above in detail. Lens 7110 focuses an area 7112 (in some embodiments, the field of view extends beyond the edges of the top surface 2005 of the I-beam 2001) onto the imaging element of imager 7105. Imager 7105 is in bidirectional communication with computer 7070 via a bus 7106. Electrical power is provided to all components by a power supply 7120, which may be attached to the pole 7010 or carried by the operator. For simplicity, the power supply 7120 is not shown in
In a first mode of operation of the weld site locating system 7000, an operator first places the pole end 7020 into physical contact with the welding site 2008, and then moves pole 7010 into a vertical position using the level 7050. The operator then depresses the trigger switch 7060 for a short period of time (e.g., approximately 1 second), which closes the switch 7060 and sends a signal to the computer 7070 via wires 7061 and 7062. In response to closure of the switch 7060, computer 7070 inputs the then-current RTK-corrected GPS location of the antenna 7011 (i.e., the phase center of antenna 7011) from the receiver 7013 via bus 7100 and performs a vertical offset calculation (based upon the length of pole 7010) to calculate the GPS/RTK position of the welding site 2008. This offset corrected welding site GPS/RTK positional data is stored into the data memory of computer 7070.
The operator then sequentially repeats the above process for each welding site located on the top surface 2005 of the I-beam 2001 so that the GPS/RTK-offset corrected positions of all welding sites have been determined and saved into the computer 7070. Having obtained all of the welding site locational data, the operator may then depress the switch 7060 for a longer period of time (e.g., approximately 5 seconds) than the period of time that was previously used to input welding site location data. The longer depression signal sent to switch 7060 communicates to the computer 7070 that the recording process has ended, and that all weld site location data is to be transmitted to welding system 2010. This data can then be used to construct a positional map of all of the recorded welding sites located on the top surface 2005 of the I-beam 2001.
As noted above, antenna 7090 is in electrical communication with computer 7070 via electrical cable 7095 and is operably configured to transmit to and receive Wi-Fi signals from, for example, the welding system 2010 via the Wi-Fi connection (or other suitable communication channel established between the computer 7070 and the computer 2595 of the welding system). Having received the GPS/RTK welding site location data, welding system 2010 may then proceed to weld studs at the appropriate sites, as discussed above in detail.
Alternately, the welding site location data which has been stored in data memory of computer 7070 can be loaded into a portable data storage device, such as a USB memory stick, which may then be inserted into a communication port of computer 2595. Welding site location data is then loaded from the USB memory stick into data memory 2720 of computer 2595.
In a second mode of operation of the weld site locating system 7000, an operator first places pole end 7020 onto the top surface 2005 of the I-beam 2001 in close proximity to at least one welding site 2008 and then moves pole 7010 into a vertical position using level 7050. The operator then depresses trigger switch 7060 for two short periods of time (e.g., each approximately 1 second), which closes the switch 7060 and signals the computer 7070 via lines 7061 and 7062. In response to the two closures of the switch 7060, computer 7070 inputs the current RTK-corrected GPS location of antenna 7011 (i.e., the phase center of antenna 7011) from the receiver 7013 via bus 7100 and performs a vertical offset calculation (based upon the length of pole 7010) to calculate the GPS/RTK location of the pole end 7020 (which is still in contact with beam surface 2005). This offset corrected welding site GPS/RTK positional data is stored into the data memory of computer 7070.
In further response to the double switch closure, computer 7070 triggers camera 7105 to image the at least one welding site 2008 (or multiple welding sites within the area 7112) via the image acquisition software 7076. Based upon this calibrated image, the computer 7070 computes the GPS/RTK locations of each welding site contained within the area 7112. This welding site location data is then stored in the data memory of computer 7070, which in a similar fashion as described above, may be transmitted to computer 2595 wirelessly via Wi-Fi or via a USB memory stick. Pole 7010 may also include a ferrule placement apparatus which is operably configured to place a ferrule at each welding site.
Although exemplary implementations of the herein described systems and methods have been described in detail above, those skilled in the art will readily appreciate that many additional modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of the herein described systems and methods. Accordingly, these and all such modifications are intended to be included within the scope of the herein described systems and methods. The herein described systems and methods may be better defined by the following exemplary claims.
Number | Date | Country | |
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62319978 | Apr 2016 | US |