The present application relates generally to robotic part processing, and more particularly to robotic part transfer systems and methods for presenting parts or workpieces to a processing machine and receiving processed workpieces from the processing machine.
Robotic part transfer systems or machine tending systems for use with processing machines such as CNC machines are known. A variety of different approaches for presenting workpieces to the robot and receiving processed workpieces from the robot exist. For example, fixed table systems may present workpieces to a robot. The workpieces are arranged in a known configuration on the table top for removal by the robot and placement into a workspace of a processing machine. The capacity of the table is limited by the size of the table, although in some applications the workpieces may be stacked onto one another. The stacks, however, can only be so high before they become unstable.
Alternatively, drawer systems exist which provide an enclosure with a plurality of drawers, each holding a plurality of workpieces. This may increase the number of parts presented to the robot relative to a fixed table system, but such drawer systems are extremely expensive, due primarily to the industrial slides and bearings needed for each drawer to meet the load capacity of the workpieces in the drawer. Additionally, in certain applications an independent device is needed to open the drawers for the robot, which adds complexity and cost to the system. Otherwise, the robot must have sufficient payload capacity to pull the drawer full of workpieces, which may add cost to the robot. In any case, the programming complexity and calibration necessary for use of such drawer systems is substantially greater than a fixed table system, and the drawer systems are inevitably less reliable.
In still further alternative approaches, conveyor systems, hoppers, vibration bowls, part chutes, vision systems, stacking systems, or chute systems are used for machine tending. However, each of these approaches is deficient or limited in terms of capacity, complexity, cost, ease of programming, capability of handling high-mix manufacturing, or some combination of these.
Stackable trays of workpieces may be used to present parts to the robot, but the existing systems typically require a very large, high payload robot because the robot must lift entire trays of processed workpieces. More specifically, in some such systems the robot loads workpieces into a processing machine individually from a top tray in a stack of trays. The robot then places the processed workpieces back on the top tray when the processing is complete. Eventually, the top tray is full of processed workpieces, and the robot lifts the entire tray of processed workpieces and moves the tray to completed stack. This requires a high payload, which increases the cost of the robot. While a dedicated system designed to move trays of workpieces to the robot and return trays of processed workpieces may be provided, such a system also greatly increases cost and complexity.
Accordingly, it is desirable to provide a tray system for robotic part processing that is low cost, simple, configurable, and capable of accommodating a large capacity of parts of various dimensions with a small footprint.
In one embodiment of the present disclosure, a tray system for robotic part processing is provided, comprising: a plurality of substantially identical trays, each tray including a base having an upper surface and a lower surface, a frame connected to the upper surface of the base and defining a plurality of pockets for receiving workpieces, and a plurality of spacers, each spacer including an alignment feature on one of the upper surface or the lower surface of the base, and at least one stacking post on another of the upper surface or the lower surface of the base of each of the plurality of trays, each stacking post including one end having a centering tip and another end configured to mate with another stacking post: wherein the trays are configured to be stacked in alignment with one another by placing the plurality of alignment features of one tray into engagement with the plurality of spacers of another tray. In one aspect of this embodiment, the other end of each stacking post is an alignment end having an interior surface shaped to receive a centering tip of another stacking post. In a variant of this aspect, each stacking post includes a threaded opening that extends between the one end and the alignment end. In a further variant, each of the plurality of spacers further includes a bolt including a head, the bolt being configured to extend through an alignment feature and the base of a tray, and to be threaded into the threaded opening of the at least one stacking post, thereby causing the head of the bolt to seat within a recess of the alignment feature and connecting the alignment feature and the at least one stacking post to the base. A still further variant, further comprises a plurality of solid spacers positioned between the base and the frame, the bolt of each of the plurality of spacers extending though one of the plurality of solid spacers. In another aspect of this embodiment, each alignment feature includes a beveled surface and a central opening and each centering tip includes a tapered end and a tip, the tapered end being configured to cooperate with the beveled surface to position the tip within the central opening of the alignment feature. In another aspect, each alignment feature is connected to the lower surface of the base and each of the at least one stacking posts is connected to the upper surface of the base of each of the plurality of trays; and wherein the trays are configured to be stacked in alignment with one another by placing the alignment features of an upper tray onto the centering tips of the at least one stacking post connected to a lower tray. In yet another aspect, the tray system further comprises a plurality of substantially identical supports for carrying any one or more of the plurality of trays, each support including a base having an upper surface and a plurality of alignment members on the upper surface, the plurality of alignment members of each support being configured to mate with a corresponding plurality of alignment features connected to the lower surface of the base of any one of the plurality of trays to position the tray in a predetermined location and orientation on the support. In a variant of this aspect, each support is a cart including a plurality of wheels connected to a lower surface of the base of the support. Another variant further comprises a docking station including at least one dock, each of the at least one dock being configured to position any support of the plurality of supports in a predetermined location and orientation. In another variant, the docking station is mounted on a processing machine. In yet another variant, each of the supports includes a docking member and each of the at least one dock includes a mating component configured to mate with the docking member of any support of the plurality of supports to position the support. In another variant, a first dock of the at least one dock of the docking station is configured to position a first support functioning as an infeed support, a second dock is configured to position a second support functioning as an outfeed support, and a third dock is configured to position a third support functioning as a robot support. In a further variant, the robot support includes a robot for moving workpieces from at least one tray on the infeed support to a workspace of a processing machine and from the workspace to at least one tray on the outfeed support, and for removing empty trays from the infeed support and stacking the empty trays on the outfeed support. In yet another aspect of this embodiment, the tray system further comprises a first dock configured to mate with a mating component on a first support functioning as a robot support, and a second dock mounted on the robot support and configured to mate with a mating component on a second support functioning as an infeed support. A variant of this aspect further comprises a third dock mounted on the robot support and configured to mate with a mating component on a third support functioning as an outfeed support. In another variant, the first dock is mounted on a processing machine. In another aspect, each of the supports includes a height adjustor operably coupled to the base and configured to position the upper surface of the base at any of a plurality of vertical positions. In another aspect of this embodiment, the other end of each stacking post is a threaded end configured to thread into a threaded opening formed in the upper surface of the base of each of the plurality of trays and the one end of each stacking post is a threaded opening configured to receive a threaded end of another stacking post. In a variant of this aspect, the threaded opening of each stacking post is also configured to receive a threaded end of a centering tip of the spacer. In still another aspect, each tray of the plurality of trays includes a first mating structure configured to mate with a second mating structure of an arm of a robot to facilitate lifting the tray and moving the tray from one location to another location. In a variant of this aspect, the first mating structure is on the frame of the tray. In a further variant, the first mating structure is one of attached to or integral with at least one of the plurality of spacers of the tray. In yet another variant, the first mating structure is an engagement block mounted to the tray and the second mating structure is a mating block mounted to an arm of the robot, the engagement block including a plurality of non-parallel bores and the mating block including a fixed pin configured to be received by a first bore of the plurality of non-parallel bores and a movable pin configured to be received by a second bore of the plurality of non-parallel bores. In a further variant, the movable pin is biased by a biasing member toward an extended position and is retracted by an actuator toward a retracted position. In another aspect, each tray of the plurality of trays includes a hook attached to the tray at a position offset from a center line of the tray, the hook being configured to mate with an interlock hook coupled to an arm of a robot to facilitate lifting the tray and moving it from one location to another location. In a variant of this aspect, each hook is attached to the frame of the tray.
In another embodiment, the present disclosure provides a tray for use in robotic part processing, comprising: a base including an upper surface and a lower surface: a frame connected to the upper surface and including a plurality of segments defining a plurality of pockets: a plurality of alignment features on one of the upper surface or the lower surface of the base; and a plurality of spacers integrally formed on another of the upper surface or the lower surface of the base, each spacer being configured to engage with an alignment feature on one of an upper surface or a lower surface of a base of a different tray.
In yet another embodiment, the present disclosure provides a tray for use in robotic part processing, comprising: a base including an upper surface and a lower surface: a frame connected to the upper surface and including a plurality of segments defining a plurality of pockets; and a plurality of spacers coupled to the base, the plurality of spacers including a plurality of alignment features positioned adjacent one of the upper surface or the lower surface of the base, a plurality of stackable posts positioned adjacent another of the upper surface or the lower surface of the base, each stackable post having a centering end and an alignment end, and a plurality of bolts configured to couple the plurality of alignment features and the plurality of stackable posts to the base: wherein the centering end of each of the stackable posts is configured to mate with any of the plurality of alignment features and any of the alignments ends of other stackable posts to increase the length of the spacer. In one aspect of this embodiment, the tray further comprises a pad attached to the upper surface of the base. In another aspect, each of the alignment ends of the stackable posts includes an interior surface shaped to receive a centering end of another stackable post. In another aspect, each of the plurality of bolts includes a head, the bolt being configured to extend through an alignment feature and the base of a tray, and to be threaded into a central threaded opening of a stackable post, thereby causing the head of the bolt to seat within a recess of the alignment feature and connecting the alignment feature and the stackable post to the base. In a variant of this aspect, the central threaded opening extends from the centering end of the stackable post to the alignment end of the stackable post.
In still another embodiment, the present disclosure provides a method of robotic workpiece transfer, comprising: positioning a robot relative to a workspace of a processing machine: positioning an infeed support relative to the robot: determining a coordinate system of the infeed support relative to a base of the robot from fixed features on the infeed support: positioning an outfeed support relative to the robot: determining a coordinate system of the outfeed support relative to the base of the robot from fixed features on the outfeed support: calibrating a 3D space to establish a location and orientation, relative to the base of the robot, of a plurality trays positioned on the infeed support: performing a workpiece transfer sequence to transfer workpieces from a tray of the plurality of trays positioned on the infeed support, to the workspace, and to a tray on the outfeed support: repeating the workpiece transfer sequence until an uppermost tray of the plurality of trays on the infeed support is empty: determining, in response to the uppermost tray being empty, whether the empty uppermost tray is a bottom tray of the plurality of trays; and responding to the empty uppermost tray not being the bottom tray by controlling the robot to move the empty uppermost tray onto an uppermost tray on the outfeed support and repeating the workpiece transfer sequence, the repeating step and the determining step. In one aspect of this embodiment, performing a workpiece transfer sequence includes controlling the robot to remove a workpiece from an uppermost tray of a stack of trays on the infeed support: controlling the robot to place the removed workpiece in the workspace to be processed into a processed workpiece: controlling the robot to remove the processed workpiece from the workspace; and controlling the robot to place the processed workpiece into an uppermost tray on the outfeed support. In another aspect, calibrating the 3D space includes teaching the robot positions of three points on each tray. In another aspect, calibrating the 3D space includes receiving a stacking height between adjacent trays. In a variant of this aspect, the stacking height between all adjacent trays of the plurality of trays is the same. Another aspect of this embodiment further comprises receiving a definition of spacing of pockets of the plurality of trays. In another aspect, determining a coordinate system of the infeed support includes the robot gripping at least three alignment members on the infeed support and contacting an upper surface of the infeed support. In another aspect, calibrating a 3D space further includes the robot gripping at least three spacers attached to a tray of the plurality of trays and determining a stacking height between the tray and another tray of the plurality of trays stacked on the tray. Another aspect further comprises receiving definitions of trays positioned on the infeed support and holding workpieces, the definitions including a stacking height between trays and the location and orientation of pockets for workpieces on the trays. In a variant of this aspect, receiving definitions of trays includes reading one of an RFID or a QR code associated with each tray. Another aspect of this embodiment further comprises responding to the empty uppermost tray of the plurality of trays on the infeed support being the bottom tray of the plurality of trays by determining whether an additional infeed support with a plurality of trays is available; and responding to an additional infeed support being available by using the infeed support as an outfeed support and using the additional infeed support as the infeed support, and repeating the workpiece transfer sequence, the repeating step, the determining step, and the step of responding to the empty uppermost tray of the plurality of trays on the infeed support not being the bottom tray.
The above mentioned and other features of this disclosure, and the manner of attaining them, will become more apparent and the disclosure itself will be better understood by reference to the following description of embodiments of the disclosure taken in conjunction with the accompanying drawings, wherein:
Corresponding reference characters may indicate corresponding parts throughout the several views.
It is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including.” “comprising.” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.
While the structures and components disclosed herein may be embodied in many different forms, several specific embodiments are discussed herein with the understanding that the embodiments described in the present disclosure are to be considered only exemplifications of the principles described herein, and the disclosure is not intended to be limited to the embodiments illustrated.
Referring now to
The docking station 18 generally includes a base 22 that is substantially flat and low-profile. The base 22 may be attached to the floor using any of a variety of attachment devices such as fasteners, etc. The base 22 includes a plurality of docks 24A-C that are spaced apart from one another along the length of the base 22. The docks 24A-C are configured with a forward edge 26 that is sufficiently low that a forward edge 34 of a support 20A-C can move into the docks 24A-C. The docks 24A-C include a mating component (not shown) that is configured to mate with a corresponding docking member 40 of a support 20A-C. The mating component and docking member 40 can take any of a variety of different forms, such as mechanical connectors, electro-mechanical connectors, spring-loaded ball and detent components, magnetic components, and/or simply a protrusion and recess connection between the mating component and the docking member 40. In any event, the docking member 40) is positioned within the dock 24A-C in a precise location by the mating component to orient the support 20A-C and the contents of the support 20A-C for part processing as is further described below. It should be understood that while three docks 24A-C are shown on the example docking station 18, more or fewer docks may be used.
In one embodiment, the supports 20A-C are substantially identical and interchangeable. Accordingly, only one support 20A is described in detail herein. The support 20A generally includes a base 28 having an upper surface 30, a lower surface 32, a forward edge 34, a rearward edge 36, a plurality of wheels 38 connected to the lower surface 32 of the base 28, a docking member 40 connected to the lower surface 32 of the base 28 adjacent the forward edge 34, alignment members 42 mounted to the upper surface of the base 28, and a handle 44 for moving the support 20A from location to location. The alignment members 42 are configured to precisely position a tray on the support 20A as is further described below. In the embodiment shown, four alignment members 42 are used, one adjacent each corner of the base 28 of the support 20A. It should be understood, however, that more or fewer alignment members 42 may be used as is further described below: Also, the handle 44 may be permanently attached to the support 20A or removably attached to the support 20A. In other embodiments, the support 20A does not include a handle 44 at all.
Referring now to
Referring back to
As shown, in the depicted embodiment the infeed support 20A is moved to dock with dock 24A, the robot support 20B is moved to dock with dock 24B, and the outfeed support 20C is moved to dock with dock 24C. When all of the supports 20A-C are docked in the docking station 18, the locations and orientations of the supports 20A-C will correspond to locations and orientations programmed into the controller 14 of the processing machine 12 or a separate controller. In other words, the controller 14 (or an additional robot controller) is programmed to know the location and geometry of the workspace 16, the robot 46, the docking station 18, the supports 20A-C, the trays 56 (described below) on the supports 20A-C, and the workpieces in the trays 56 so that when the components of the tray system 10 are in place the robot 46 will be controllable to move to precise locations on the infeed support 20A, the outfeed support 20C and the workspace 16. In other embodiments and as is further described below; when the components of the tray system 10 are in place, the robot 46 may be taught the locations and geometries of the supports 20A-C and the workspace 16 by manually jogging or teaching the robot 46, using force sensors (not shown) on the robot 46 to detect objects, using a vision system (not shown) in conjunction with the robot 46, etc. or some combination of these methods as are known in the art.
Referring now to
Referring now to
The pad 60 is also generally planar and rectangular in shape and includes an upper surface 61 and a lower surface 63. The pad 60 is made of a somewhat resilient material such as rubber and is attached at its lower surface 63 to the upper surface 70 of the base 58. The pad 60 functions as the contact surface for the workpieces that are loaded onto the tray 56.
The frame 62 of the tray 56 may be any of a variety of sizes and shapes for accommodating workpieces having different geometries as is further described herein. In one embodiment, the frame 62 may be formed in the manner described in co-pending U.S. Patent application Ser. No. 17,844,895 (Attorney Docket No. HUR-0229-01-US), filed on Jun. 21, 2022 and entitled “CONFIGURABLE CAPACITY GRID TRAY FOR ROBOT PART HANDLING” (hereinafter, “the '895 Application”), the entire contents of which being expressly incorporated herein by reference. In the depicted embodiment, the frame 62 generally includes end segments 86, width segments 88, and length segments 90, which together form a plurality of pockets 92 for receiving workpieces and processed parts as is further described herein. As shown, the segments 86, 88, 90 of the frame 62 generally form a grid of pockets 92 which, in this example, are substantially the same size and shape. It should be understood, however, that the segments 86, 88, 90 of the frame 62 may be modified to form larger or smaller pockets 92, more or fewer pockets 92, and/or pockets 92 of different sizes within the frame 62. The frame 62 further includes a plurality of apertures 94 configured to receive fasteners (not shown) to connect the frame 62 to the stand-offs 64. In the depicted embodiment, four apertures 94 are shown disposed adjacent ends of the end segments 86. It should be understood, however, that more or fewer apertures 94 may be used and they may be located at different locations on the frame 62.
It should also be understood that the frame 62 may be integral with the base 58. In this embodiment, the tray 56 may be substantially one-piece (aside from the spacers 100 described below) wherein pockets are machined into a plate (e.g., an aluminum sheet) to hold parts. The pockets may be useful for irregularly sized workpieces 109 that may not sit in a stable position on a flat surface.
In one embodiment, the frame 62 also includes a hook 96 mounted adjacent an intersection between a width segment 88 and a length segment 90. The hook 96 is configured to provide a pickup location for the tray 56 as is further described below. As shown, the hook 96 is located at a position offset from a center line 98 of the tray 56. As is described below, this location facilitates the use of gravity to maintain the tray 56 is a stable position as it is moved from one location to another by the robot 46. The hook 96 is shown and described in more detail with reference to
Each stand-off 64 includes a body 65 having a threaded opening 67 at one end for receiving a fastener extending though an aperture 94 of the frame 62 to connect the frame 62 to the stand-off 64, and a threaded end 66 for threading the stand-off 64 into one of the threaded openings 69 of the based 58. In certain embodiments, the stand-offs 64 and accompanying openings may be omitted and the frame 62 may be mounted directly to the base 58 of the tray 56, or the frame 62 may be supported above the base 58 and the pad 60 by the spacers 100, 100′, 100″ and/or 600 described below.
As is further described below, the trays 56 according to the present disclosure are stacked to increase the holding capacity of the supports 20. To facilitate such stacking, configurable spacers 100 are connected to each tray 56. Referring to
Each stacking post 104 includes a body 120 having a plurality of flat portions 122 on its outer surface (e.g., a hex-shaped body), a threaded opening 124 and a threaded end 126. The threaded end 112 of the centering tip 102 may be threaded into the threaded opening 124 of the stacking post 104. The body of the centering tip 102 may be oval or include flats to permit use of a wrench to tightly thread the centering tip 102 into the stacking post 104. It should be understood that the threaded opening 124 of the stacking post 104 may also receive the threaded end 126 of another stacking post 104, thereby permitting multiple stacking posts 104 to be used to adjust the vertical distance between adjacent stacked trays 56. It should also be understood that the stacking posts 104 may be different lengths to provide even further adjustability to the vertical distance between adjacent trays 56. In alternative embodiments, the spacers 100 may include an alignment feature and the lower surface 72 of the tray 56 may include a centering feature such as the centering tip 102.
Referring now to
The second tray 56B is configured to receive taller workpieces 111. Specifically, three stacking posts 104 are used for each spacer 100 attached to the second tray 56B to provide sufficient vertical distance between the second tray 56B and the third tray 56C to accommodate the height of the workpieces 111. Additionally, the frame 62 of the second tray 56B is an alternative embodiment frame which extends between the spacers 100 instead of being attached to the second tray using stand-offs 64 as described above with reference to the tray 56 of
The alignment features 84 of the third tray 56C are positioned onto the centering tips 102 of the spacers 100 of the second tray 56B, thereby positioning the third tray 56C precisely above the second tray 56B. The third tray 56C is configured such that the frame 62 is mounted directly onto the pad 60) using fasteners (not shown) that extend through the apertures 94 of the frame 62 and into the second set of threaded openings 69 of the base 58 of the third tray 56C. This creates shallow pockets 92 in the third tray 56C which position the bases of the frustoconical third workpieces 113.
As should be apparent from the foregoing, the spacers 100 may be customized and configured to accommodate workpieces of different height. Additionally, the frames 62 may be supported at different distances above the bases 58 of the trays 56. Moreover, the frames 62 may be configured to provide different sized pockets 92, spaced apart with different spacings, using a configurable frame such as that disclosed in the '895 Application mentioned above or otherwise. In this manner, substantially identical trays 56 may be easily configured using common components to accommodate different numbers and sizes of workpieces, while still stacking in a consistent arrangement as depicted in
Referring now to
Yet another embodiment of a spacer according to the present disclosure is depicted in
A threaded, headless bolt (not shown) may be partially threaded into the threaded opening 124 of one post 104 and the alignment end 121 of another post 104 may be threaded onto the headless bolt, thereby permitting the posts 104 to be stacked and secured to one another as shown with the tray 56 in the middle of
Referring now to the sequence of actions depicted in
While the example depicted in
It should further be understood that in other applications an outfeed cart may not be used at all. Instead, an alternative device is used for outfeed of processed parts. For example, in some applications a conveyor may move parts out from the processing machine 12, or a transfer robot may move parts to a palletizer or transfer them to another processing machine 12 for subsequent processing. All of these applications are contemplated by the present disclosure.
Returning to the example depicted in
Again, the robot 46 then lifts the empty tray A2 from the infeed support 20A and stacks it on top of the tray A1 on the outfeed support 20C as shown in
At this point, the support 20A may now function as an outfeed support. Another support 20D with trays D1-D8 full of workpieces 109 may be present or moved into position adjacent the support 20A. This is shown in
Referring now to
As shown in
The interlock hook 166 according to one embodiment includes an upper wall 170 having a having a first segment 172 and a second segment 174 extending perpendicularly relative to the first segment 172, a vertical wall 176 having a first segment 178 extending perpendicularly relative to a plane including the upper wall 170 and a second segment 180 extending perpendicularly relative to the first segment 178 and relative to the plane including the upper wall 170. The interlock hook 166 also includes a mounting wall 182 having a first segment 184 extending perpendicularly relative to the first segment 178 of the vertical wall 176 and parallel to the plane including the upper wall 170 and a second segment 186 (
The first segment 184 and the second segment 186 of the mounting wall 182 are attached to the outer surface 152 of the side plate 148 of the wrist attachment 146 using any suitable attachment method such as fasteners, welding, etc. The mounting wall 182 is attached to the outer surface 152 of the side plate 148 at a location adjacent to the intersection between the first side edge 156 of the side plate 148 and the inner edge 162 of the side plate 148. In this manner, the first segment 172 of the upper wall 170 of the interlock hook 166 extends away from the first segment 178 of the vertical wall 176 toward the first side edge 156 of the side plate 148 in substantially parallel relationship to the outer surface 152 of the side plate 148 and the second segment 174 of the upper wall 170 extends away from the second segment 180 of the vertical wall 176 toward the inner edge 162 of the side plate 148 in substantially parallel relationship to the outer surface 152 of the side plate 148. As such, the vertical wall 176 supports the upper wall 170 at a spaced apart distance from the outer surface 152 of the side plate 148 to provide for engagement with the hook 96 attached to the frame 62 of the tray 56 as described below for lifting and moving the tray 56.
The engagement pad 168 depicted in
Referring now to
As shown, the connecting plate 150 of the wrist attachment 146 is attached to an end surface 192 of the robot arm segment 50. In one embodiment, the wrist attachment 146 is sandwiched between the wrist 53 of the robot 46 and the end surface 192 of the arm segment 50. The wrist 53 may be attached to the connecting plate 150 and the robot arm segment 50) using bolts or other fasteners that extend through the apertures 164 (
In other embodiments of the present disclosure, alternative mechanisms may be used for engaging and moving the tray 56 (i.e., instead of the hook 96 and the interlock hook 166). For example, one of the robot 46 or the tray 56 may include a key structure, and the other may include a keyhole structure. Alternatively, a spring-loaded latch may be used that is mechanically (e.g., pneumatically) unlatched by an actuator or force applied by the robot 46. In yet another alternative, a mechanically actuated latch may be used for locking and unlocking to a pin or hook (e.g., a pneumatic piston lock). Alternatively, the robot 46 may magnetically engage and disengage the tray 56. These mating structures may be part of the tray 56 or part of the spacer 100. Rather than being part of the spacer 100, the mating structure (e.g., the pin/hook example mentioned above) could be bolted between stacking posts 104. Any and all of these alternatives are contemplated by the present disclosure.
One example alternative for engaging and moving a tray 56 is the engagement mechanism 398 depicted in
The engagement mechanism 398 also includes mating block 424 as shown in
The mating block 424 also includes a latch assembly 452 disposed on the second portion 442 of the mating block 424. The latch assembly 452 includes a movable pin 454 including a shaft 456 and a tapered end 458, a rod 460) connected to the shaft 456, and a biasing member 462. The latch assembly 452 is positioned in a bore 464 formed into the second inner surface 438 of the second portion 442 of the mating block 424. More specifically, the bore 464 includes an opening 466 in the second inner surface 438, a side wall 468, a shoulder 470) and an rod opening 472. The biasing member 462 in this embodiment is a coil spring. The rod 460 extends through the central portion of the biasing member 462. One end of the biasing member 462 engages an end 474 of the shaft 456 of the movable pin 454, and another end of the biasing member 462 engages the shoulder 470 of the bore 464. The rod 460 is retractable by an actuator (not shown) along its longitudinal axis to move the movable pin 454 to a retracted position wherein the pin 454 is substantially entirely disposed within the bore 464, thereby compressing the biasing member 462. The actuator may be mechanical, pneumatic, electrical or magnetic. When the actuator is deactivated, the biasing member 462 expands causing the pin 454 to move to an extended position as shown in
In operation, the robot 42 is programmed or learns the mounting location of the engagement block 400 on the tray 56. When a tray 56 is to be picked up and moved to another location, the robot 42 activates the actuator to cause the movable pin 454 to move to the retracted position and moves the mating block 424 into engagement with the engagement block 400 such that the fixed pin 444 is inserted into the bore 412. In this position, the movable pin 454, retracted in the bore 464, is aligned with the bore 416 on the second outer surface 404 of the engagement block 400. The robot 42 then deactivates the actuator, which permits the biasing member 464 to move the movable pin 454 into the extended position, which inserts the moveable pin 454 into the bore 416. The mating block 424 is thus fixed to the engagement block 400 by the fixed pin 444 and the movable pin 454. The robot 42 then moves the tray 56 to desired location, activates the actuator to move the movable pin 454 into the retracted position, and moves the mating block 424 to withdraw the fixed pin 444 from the bore 412, thereby disengaging the mating block 424 from the engagement block 400.
Referring now to
In other embodiments, the docking station 18 is omitted and other methods for orienting the supports 20 relative to the processing machine 12 and the robot 46 are used. For example, a support 20 may be moved manually to a position near the robot 46 and the wheels 38 on the support 20 may be locked to prevent it from moving. The robot 46 and the controller 14 may then be used to locate the position and orientation of the support 20. The robot program may then automatically adjust itself accordingly to remove the workpieces from the trays 56 on the support 20 and move the trays 56 in the manner described below. The location and orientation of the support 20 may be determined either by teaching positions with the robot 46 or by running an automatic cycle using robot force sensors to find the location of the support 20, or a combination of the two, where an operator moves the gripper 52 of the robot 46, for example, close to the support 20 and the robot 46 then executes an automatic cycle to find the support 20 using force sensing capabilities of the robot 46. In a further alternative, sensors or cameras may be used to detect and/or determine the location and orientation of the support 20 relative to the robot 46.
At step 208 the robot 46 begins moving workpieces from the infeed support 20 to the workspace 16, and moving processed workpieces from the workspace 16 to the outfeed support 20. Specifically, at step 208 the robot 46 is controlled to remove a workpiece from an uppermost tray 56 of a stack of trays 56 stacked on the infeed support 20. An example of this is depicted in
It should be understood that while a robot 46 including a single gripper 52 is shown and described herein, the present disclosure contemplates use of a robot 46 having two or more grippers 52 mounted on corresponding arm segments 50. For example, the robot 46 may include two grippers 52 and the steps 208, 210, 212 and 214 of
At step 216 the controller 14 determines whether the uppermost tray 56 of the stack of trays 56 on the infeed support 20 is empty. If not, then the process returns to step 208 and repeats steps 210, 212 and 214. If the uppermost tray 56 of the stack of trays 56 on the infeed support 20 is empty (as depicted in the example of
It should be understood that according to embodiments of the disclosure, the trays 56 need not be stacked onto moveable objects such as supports 20. Instead, stacks of trays 56 may be presented to the robot 46 on a pallet or other supporting surface and empty trays 56 may be stacked onto another pallet or other supporting surface. Also, as should be apparent from the foregoing, the spacing and size of the pockets 92 of the frame 62 of a tray 56 containing workpieces 109 at the top of a stack of trays 56 on an infeed support 20 should be capable of accommodating the size of processed workpieces 109′ from the next lower tray 56 in the stack. In other embodiments, an additional support 20 may be provided with a stack of empty trays 56 that matches the trays 56 on the infeed support 20. Those empty trays 20 may be loaded onto the outfeed support 20. In this embodiment, an additional support 20 would be needed to receive the empty trays 56 from the infeed support 20 since they will not be used to receive processed workpieces 109″.
As should be further understood from the foregoing, the controller 14 of the processing machine 12 or a separate controller knows, through user input or by means of detection and learning, the locations of the infeed support(s) 20 and the outfeed support 20, the spacing of the pockets 92 in each tray 56 on the supports 20, the dimensions of the workpieces 109 in each tray 56, and the vertical distance or height between adjacent stacked trays 56. This information may be saved and recalled for subsequent processing. Alternatively, the data may be stored on the supports 20 and transmitted to the controller 14 using RFID, QR code or other similar technology.
Referring now to
The operator can also update or define the actual length and width of pockets 92 of the tray 56 by filling in fields 534 and 536 and clicking on icon 538. Boxes 540 and 542 permit the operator to input the grid dimensions in millimeters or inches, respectively. Finally, the operator may save the tray configuration by clicking on icon 544 and proceed to define the next tray 56. Icon 546 permits the operator to load a previously defined tray configuration stored on memory accessible by controller 14.
It should be understood that while in the above examples, the infeed trays 56 and their associated jobs are defined using the job manager software upfront before running the system, the definitions of the infeed trays 56, their associated jobs and even the number of trays 56 to process can be defined remotely, outside of the job manager software, on a network, or be encoded or linked to in an RFID or QR code on the trays 56. When the job manager software is started, the system may search for and detect the RFID or QR code of upper most available tray 56 in the infeed stack and begin processing the job(s) in that tray 56. The system would then repeat until no further unprocessed trays 56 are detected in the infeed stack. The feature also allows for the possibility to use autonomous vehicles for the infeed and outfeed supports 20 for continual autonomous production of parts. The system would then simply wait until the infeed support 20 and the outfeed support 20 are present to begin processing jobs.
It should be further understood that the base location of the infeed support(s) 20 and the outfeed support(s) 20 is fixed and can be taught using the robot 46. This can be done by teaching the robot 46 the relative spatial location of fixed features on the supports 20, storing those locations to determine a fixed relative coordinate system on the support 20, then interpolating the relative locations of the stacked trays 56 based on the definitions of the trays 56 (i.e., dimensions and spacing between trays 56 in the stack). When locked in position, the infeed support 20 and the outfeed support 20 locations and orientations (of all supports 20 presently available in the system) are defined by coordinate systems relative to the robot base 48 which allows the system to compute the necessary joint positions of the robot 46 to pick and place the workpieces 109. This is shown in
Alternatively, each tray 56 location and orientation can be taught using the robot 46 in a similar way. For example,
While calibrating the 3D space can be done by guiding the robot 46 to fixed points on the grid of each tray 56 in the stack, this process may be tedious and time-consuming. Alternatively, the design of the stacked trays 56 may have predetermined dimensions in the plane of the frame 62 and in the stacking height between trays 56. Referring to
The auto calibration cycle will rely on the fact that there is a fixed height 600 for all the stacked parts and fixed dimension of the trays 56 that will allow the system to establish a coordinate system and fixed points across the tray 56 to map and interpolate the robot positions to the calibrated 3D space. The spacing of the pockets 92 in the tray 56 can be programmed in the job manager software and will not affect the calibration cycle.
In certain embodiments, the base location of the docked support 20 is first taught to the robot 46. In the embodiment depicted in
Using the coordinate system and mapping with the three alignment members 42A-C, the automatic cycle runs to position the robot 46 around the remaining alignment members 42, followed by commanding the robot into free-drive mode and clamping the gripper fingers 54 onto the alignment members 42. The robot will self-center on the alignment members 42 and the robot position is then stored. There is sufficient accuracy to find each of the alignment members 42 using the baseline coordinate system established first with the three alignment members 42A-C.
Following the base support calibration, a first tray 56 can be stacked on the alignment members 42 of the support 20 and the spacers 100′ of the tray 56 can be similarly measured and stored. A next tray 56 can then be stacked and automatically measured. This process continues until the full stack of trays 56 have been measured. The trays 56 should ideally be of the same spacing to map the full 3D array of trays 56. If the stack spacing between trays is changed for shorter or taller parts, the system will simply interpolate the tray location accordingly. Thus, the system can compute the locations for any tray 56 within the mapped 3D volume. Note that both the infeed support 20 and the outfeed support 20 would need to be calibrated using this method to map their respective 3D volumes accordingly.
As discussed above, each tray 56 can have different size pockets 92 defined in the job manager software. With the mapping of the six spacers 100′ of the tray 56 and their fixed relationship geometrically with the tray 56, the robot 46 can be commanded to accurately pick and place workpieces 109 in the infeed trays 56 and outfeed trays 56 provided the mounted location and pocket dimensions of the grid tray 56 are specified in the job manager software. Each workpiece 109 location in the tray 56 can be geometrically computed and then the actual required robot position is interpolated to move the robot 46 to the correct position using the calibrated spacer 100′ locations. Hence, the calibration of the grid tray 56 using three alignment members 42A-C as discussed above would not be needed as the job manager software would now compute the grid and workpiece 109 locations and then interpolate to the mapped robot space.
As should be apparent from the foregoing, the calibration process only needs to be performed once. If the support 20 docking is not accurate or its docking location changes, the only thing that needs to be measured again will be the first three alignment members 42A-C on the support 20 to establish its new location. All other calibrated locations can be transformed to the new support 20 location, provided the new location of the support 20 is not materially different from the original calibration location. However, it is of course expected that the docking locations of the supports 20 and the robot 46 will be accurate and repeatable sufficiently so that calibration of the entire system is only needed once.
The above-described system and methods have several benefits. First, the trays 56 are only lifted by the robot 46 when they are empty. Thus, a robot 46 with lower payload capacity may be used, which reduces the cost of the overall system. Second, the supports 20, whether functioning as infeed supports or outfeed supports, are identical, which reduces the complexity of the system and lowers the cost. Third, the trays 56 are substantially identical, but can be configured using the spacers 100, 100′, 100″ to accommodate workpieces of different height. The uniformity of the trays 56 provides benefits for programming the controller 14 and the configurability provides flexibility for handling a variety of different workpieces in high-mix manufacturing.
While this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.