Methods, systems and devices for calibrating a robotic arm

Abstract

Methods and devices for calibrating a robotic arm with respect to a plurality of feeder positions are hereby provided. Such methods can calibrate the robotic arm with respect to a large number of positions while only needing to teach some. Such methods and devices can include a teaching tool with upper and lower parts, each with three pins which can align during a calibration process.

Description

[0001] Methods , Systems and devices for calibrating a robotic arm

[0002] BACKGROUND

[0003] This relates to methods , systems and devices for calibrating a robotic with respect to a plurality of feeder positions , for example , in a dispensing device for dispensing discrete medicaments such as pharmaceuticals , medicaments , pills , tablets or capsules for medical use .

[0004] US 2014 / 0366489 Al discloses a device for dispensing solid substances for medical use . The device is provided with a great number of feeder units , also known as 'canisters ' , distributed in a radial grid forming an array feeder positions about a rotation axis with a robotic manipulator with arm in a center of the radial grid . Each feeder unit holds an amount of solid substances specific to that respective feeder unit . Hence , together, the feeder units can dispense a wide variety of solid substances .

[0005] The device is further provided with a collection frame that is rotatable about the rotation axis below the array of feeder positions . The collection frame is provided with a series of collection trays for collecting solid substances dispensed from any of the feeder units in the array of feeder positions .

[0006] The device further comprises a packaging unit arranged in a stationary position below the collection frame for packaging the solid substances received from the collection trays . The collection frame is rotated about the rotation axis such that each collection tray passes along each of the feeder units in the array of feeder positions before arriving at the packaging unit .

[0007] Typically, the robotic manipulator or robotic arm must be taught all feeder positions manually before operations . This can take a lot of time when there are lots of feeder positions .

[0008] SUMMARY OF THE INVENTION The device of US 2014 / 0366489 Al is great at continuously dispensing, collecting and packaging solid substances as long as the feeder units are reliably dispensing said solid substances . However, due to the large number of feeder positions and the complex shape with a circular table and cylindrical walls which all hold feeder units , the calibration of the robotic arm to enable the robotic arm to precisely move to and grip a feeder unit takes a long time . This is especially true for such radially arranged tables and slanted feeder position in the cylindrical housing ( sometimes called stock positions ) . Typically the calibration is done manually, needing to manually move the robotic arm into to each specific position and record its position for accurate movement in future operations .

[0009] The methods and devices herein allow for more efficient calibration of the robotic arm, even with large numbers of feeder unit positions and / or challenging positions , such as a circular table and / or on a cylindrical housing wall and / or tilted positions not in a planar grid . Thus , the system and methods enable accurate determination and movement of the robotic arm to move to all positions , ensuring operational precision without needing the time and ef fort required to manually teach each position ( as in past systems ) .

[0010] According to a first aspect , a method for calibrating a robotic arm with respect to a plurality of feeder positions in three-dimensional space is disclosed . The method comprises : i . fixing, by mechanical means ( e . g . , bolts ) , an upper teach tool to the robotic arm; ii . positioning a lower teach tool in a first feeder position; iii . automatically moving the robotic arm to the vicinity of the first feeder position; iv . manually adj usting the robotic arm position such that the upper teach tool aligns with the lower teach tool at the first feeder position; v . recording the coordinates of the robotic arm for the first feeder position; vi . repeating steps ii - v for a small set number of further feeder positions ; and vii . determining coordinates for all feeder positions of the plurality of feeder positions based on the recorded coordinates of the first feeder position and the further feeder positions .

[0011] Such a method provides an accurate and ef ficient way of calibrating a robotic arm to work in three-dimensional space without having to individually teach each position . Such a method of using a combination of automatic and manual steps to ensure ef ficient and accurate teaching; and then using that set number of taught positions to determine the remaining positions allows for ef ficient and ef fective calibration . Only teaching a smaller number of positions , for example, 5-15 or 10- 12 ; and then being able to determine or calculate the remaining number, for example , 350-450 or 400- 415, allows for a much easier teaching method and helps to prevent mistakes that could happen in having to individually teach each position . Thus , not all positions need to be individually taught , saving time and man-power in calibrating devices with a large number of feeder positions .

[0012] The upper teach tool and lower teach tool are specific devices used for such methods of calibration, not for normal operations of the robotic arm. Using the upper and lower teach tools , and connecting them to the robotic arm and a feeder position, respectively, allows for precisely and accurately calibrating the arm . The specific teach tools are designed for precise calibration purposes and mechanically fixing the upper teach tool to the robotic arm helps to ensure strict calibration requirements are met .

[0013] According to an embodiment , the upper teach tool and the lower teach tool each comprise three pins . Having a teaching tool with upper and lower parts , each with three pins allows for accurate three-dimensional alignment and positioning, even in complex geometry such as tilted feeder units and / or in a cylindrically shaped housing around the robotic arm .

[0014] According to an embodiment , the set number of further feeder positions is 2-30% of the plurality of feeder positions , for example , 3-10% of the total number of feeder positions . Thus , being able to determine all positions while only teaching a limited number saves time in the overall calibration process , while still maintaining accuracy and avoiding errors .

[0015] According to an embodiment , the method further comprises , as part of step iv . , leveling a gripper on the robotic arm . Optionally, this can be done with a spirit level or other device . Such leveling can be especially useful for ensuring the proper orientation in systems with an array of substantially planar feeder positions .

[0016] According to an embodiment , step iii . comprises automatically moving the robotic arm to within 50 mm of the first feeder position . Such automatic movement can ensure the robotic arm moves close to the taught position for ef ficiency but stays far enough away to ensure proper teaching and ensure that the robotic arm does not unintentionally contact the teaching tool (or other parts ) when its initial movements have not yet been properly calibrated .

[0017] According to an embodiment , step v . further comprises , after recording the coordinates of the robotic arm for the feeder position, moving 10- 100 mm away from the feeder position . Optionally, the movement 10-100 mm away from the feeder position is in a perpendicular direction to the planar surface of the teach tool lower part . Such movement brings the robotic arm away in such a manner to ensure that it does not contact another feeder position when re-positioning for the next teaching .

[0018] According to an embodiment , the method further comprises viii . performing a check of one or more recorded positions . This can be an automatic check whereby the robotic arm is instructed to check a few positions , or a more detailed check . Optionally, such a check comprises : instructing the robotic arm to move to a particular position in a check mode ; automatically moving the robotic arm to near the particular position; requesting confirmation to proceed to the particular position; and if the confirmation to proceed is given, moving the robotic arm to the particular position; or if the confirmation to proceed is denied, optionally perform steps iv . - v . at the particular position . Such a method can be used to check if the taught positions are correct in a safe and controlled manner, thereby allowing for re-teaching if not . Thus , this method can provide an ef ficient way of checking positioning and correcting where needed .

[0019] According to an embodiment , the plurality of feeder positions extends around a central axis , preferably wherein the robotic arm is located at or near the central axis . Optionally, the plurality of feeder positions extends in a first plane around the central axis , preferably in a radial manner, and on an inner side of a housing surrounding the robotic arm . Further optionally, the housing is substantially cylindrical in shape . Such a configuration provides a large amount of feeder positions , with a plane of positions in circular table as well as positions around the cylindrical housing which the robotic arm can reach to place and / or remove feeder units , thereby allowing for use with a large number of feeder units . The methods disclosed allow for efficient and precise calibration to access such a large number of feeder units despite the complex positions .

[0020] According to an embodiment , the plurality of feeder positions are in a dispensing device for dispensing discrete medicaments . Optionally, the dispensing device comprises a dispensing section defining an array of feeder positions for holding a plurality of feeder units , a collection section for receiving the medicaments from the dispensing section, a robotic arm; and a control unit for controlling the robotic arm, the control unit configured to perform the method as described above . Optionally, the device further comprises a packaging section for packaging the medicaments received from the collection section . Further optionally, the device comprises a housing surrounding at least part of the dispensing device . Such a dispensing device can provide a large number of feeder positions , allowing for dispensing ( and in some cases packaging) a large number of discrete medicaments ef ficiently . The ability to ef ficiently calibrate the robotic arm of such a device to the large number of feeder positions allows for getting the device up and running more ef ficiently, while still ensuring precision in movements .

[0021] According to an embodiment , an inner side of the housing comprises one or more housing feeder positions extending along one or more walls of the housing as part of the plurality of feeder positions . Optionally, the dispensing device comprises one or more doors and / or drawers and / or posts with one or more feeder positions in the one or more doors and / or drawers and / or posts as part of the plurality of feeder positions . Such additional feeder positions along the walls , and / or in or connected to doors , drawers and / or posts provides additional positions for feeder units , either for use or for replacing empty units quickly in dispensing operations . The methods disclosed can also ef ficient calibrate the robotic arm to precisely be taught these complicated positions , which are typically angled and / or not planar around cylindrical or curved walls , in an efficient manner .

[0022] According to a further aspect, a teaching tool for calibrating a robotic arm with respect to a plurality of feeder positions in three-dimensional space comprises an upper teach tool comprising a gripper connection part for connecting to the robotic arm ( e . g . , to a gripper) and three pins extending substantially perpendicularly from the upper part ; and a lower teach tool comprising a feeder position connection part and three pins extending substantially perpendicularly from the feeder position connection part . The three pins of the upper teach tool are arranged on the gripper connection part to be able to be aligned with the three pins of the lower teach tool for teaching feeder positions . Such a teaching tool can provide for ef ficiently teaching movement , and particularly movement of a robotic arm in three- dimensional space . The three pins on each of the upper and lower teach tool parts allows for precise positioning with respect to each other in three dimensions , allowing for precisely calibrating the robotic arm even in complicated spatial situations ( e . g . , for calibrating with respect to obj ects not in a single plane ) .

[0023] According to an embodiment , the configuration of the three pins on the upper teach tool and the three pins on the lower teach tool are in a L or triangle shape . Such a shape can provide a simple configuration with which to align in all dimensions during a calibrating process .

[0024] According to an embodiment , the teach tool comprises one or more sensors . This could be, for example, a movement sensor, a touch sensor and / or a 3D touch probe . Such sensors could, for example , enable even more automation of the calibration process , allowing for immediate recording and retraction as soon as a sensor has sensed touching between the pins of the touch tool parts .

[0025] The various aspects and features described and shown in the speci fication can be applied, individually, wherever possible . These individual aspects , in particular the aspects and features described in the attached dependent claims , can be made subj ect of divisional patent applications .

[0026] BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The invention will be elucidated on the basis of an embodiment shown in the attached schematic drawings , in which : figure 1 shows an isometric view of the dispensing device with a dispensing section, a collection section and a packaging section according to a first embodiment ; figure 2A show a top view of the dispensing device according to figure 1 ; figure 2B shows a front view of a feeder unit ; figure 3 a diagram of the steps of a method for calibrating the robotic arm of the dispending device ; figure 4a shows a schematic side view of a calibration tool for use with the method; figure 4b shows a schematic end view of one part of the calibration tool of fig . 4a ; figure 4c shows a perspective view of the calibration tool in use with the dispensing device ; and figure 5 shows a method for checking the calibration of the robotic arm .

[0028] DETAILED DESCRIPTION OF THE INVENTION

[0029] Figure 1 shows a dispensing device 1 according to a first embodiment for dispensing discrete medicaments , discrete solid medicaments , pharmaceuticals or solid items , articles or substances 90 for medical use , e . g . pills , tablets , capsules or the like . The medicaments are 'discrete ' in the sense that they can be dispensed one-by-one , individually, separately or in dose units .

[0030] The dispensing device 1 comprises a dispensing section 2 for dispensing the medicaments 90 , a collection section 3 for collecting the medicaments 90 from the dispensing section 2 and a packaging section 6 for packaging the medicaments 90 . The collection section 3 is located below or vertically below the dispensing section 2 . The packaging section 6 is located below or vertically below the collection section 3 . The dispensing device 1 further comprises a housing 10 for shielding the aforementioned sections 2 , 3 , 6 from unauthorized access .

[0031] The dispensing section 2 defines an array of feeder positions 20 for receiving or holding a plurality of canisters , tablet cases or feeder units 40 . Each feeder position 20 comprises a docking member or protrusion 83 for mating with or receiving a respective one of the feeder units 40 , with an appropriate aperture or channel to allow passage of dispensed medicaments 90 through the feeder position 20 into the collection section 3 underneath . The array of feeder positions 20 is distributed along an endless collection path Zl . In this example , the endless collection path Z 1 is circular or substantially circular and the array of feeder positions 20 is distributed circumferentially about a rotation axis X . More in particular, the array of feeder positions 20 is distributed circumferentially or according to a radial grid, e . g . in a plurality of radially extending rows arranged side-by-side or adj acent in a circumferential direction about the rotation axis X forming a circular table . The housing 10 extends cylindrically around the array of feeder positions 20 , though in other embodiments the housing and / or collection path could have a di fferent shape ( e . g . , oval , rectangular) . In this example , the circumferential walls of the housing 10 are provided with a plurality of stock positions 12 for holding temporarily unused or auxiliary feeder units 40 around the inside walls of the housing .

[0032] The dispensing device 1 is further provided with a robotic manipulator, which includes a robot arm 11 with gripper 13 , for automatic, automated or autonomous handling, positioning, removing and / or repositioning the feeder units 40 with respect to the array of feeder positions 20 . In this embodiment, the robotic manipulator is located at the center of the array of feeder positions 20 , e . g . close to , at or near the rotation axis X . In said position, all feeder positions 20 and stock positions 12 are within reach of the robotic arm 11 .

[0033] Figure 2B show a feeder unit 40 of the plurality of feeder units 40 in more detail . The description of the feeder unit 40 hereafter is representative for all feeder units 40 of the plurality of feeder units 40 .

[0034] As shown in figure 2B, each feeder unit 40 comprises a container 50 for holding an amount of the medicaments 90 with a composition specific to said respective feeder unit 40 . The term 'composition' is to be interpreted as the chemical or pharmaceutical composition of the medicament 90 , e . g . the combination of active ingredients , that could include slight variations . Each feeder unit 40 typically only holds a medicaments 90 of a single composition . The container 50 has a volume that may hold several hundreds or more (or less ) of the medicaments 90 , depending on their si ze and shape .

[0035] Each feeder unit 40 further comprises an outlet 51 , e . g . a fall pipe, for dispensing the medicaments 90 towards the collection section 3 and a dispensing mechanism 52 between the container 50 and the outlet 51 for controlled feeding of the medicaments 90 from the container 50 into the outlet 51 . In this embodiment, the dispensing mechanism 52 comprises a wheel that acts as a revolving door to singulate and feed the medicaments 90 one by one towards the outlet 51 . It will be apparent to one skilled in the art that alternative dispensing mechanisms may be provided which can singulate the medicaments 90 .

[0036] Each feeder unit 40 may further be provided with one or more sensors 53 , 54 , e . g . a vision camera, a photosensor, a laser sensor, a level sensor, a weight sensor or the like , for verifying the type, composition and / or integrity of the medicaments 90 , and for counting the amount of medicaments 90 that have been dispensed .

[0037] Each feeder unit 40 may also comprise a lid 43 , which can open and close for filling or emptying the feeder unit . Additionally lid 43 can include a grip ( e . g . , a smaller diameter portion 45 with a shoulder ) for gripping by the robotic arm 11 , and particularly gripper 13 .

[0038] As best seen in figure 2A, the dispensing section 2 further comprises a feeder loading member 24 with a plurality of feeder loading positions 25 for receiving new feeder units 40 into the dispensing device 1 and / or for removing feeder units 40 from the dispensing device 1 . In this example, the feeder loading member 24 is formed as a drawer . Alternatively, a door, individual locks or the like may be used . The dispensing section 2 may optionally comprise a manual loading position 26 for receiving a manual loading member (not shown) , e . g . a medicine transport plate , that is manually loaded with medicaments 90 which are unsuitable to be dispensed automatically with the aforementioned feeder units 40 .

[0039] As further shown in figure 1 , the collection section 3 comprises a plurality of collection units , in particular collection hoppers 30 , which are open at a side facing the dispensing section 2 to receive selectively dispensed medicaments 90 from one or more of the feeder units 40 . In this example , each collection hopper 30 extends underneath a plurality of feeder units 40 at the same time to receive the medicaments 90 from any of those feeder units 40 . Each collection hopper 30 tapers towards the bottom and is provided, at said bottom, with a valve (not shown) that can be operated to drop the collected medicaments 90 into the packaging section 6.

[0040] In this embodiment , the plurality of collection hoppers 30 are distributed circumferentially about the rotation axis X . More in particular, the plurality of collection hoppers 30 are held in a collection frame 32 that is movable along the endless collection path Zl , e . g . by rotating about said rotation axis X to move the plurality of collection hoppers 30 relative to the array of feeder positions 20 in the dispensing section 2 . The rotation may be a stepped rotation, wherein each step aligns the plurality of collection hoppers 30 with a next group of feeder units 40 in the array of feeder positions 20 . Each collection hopper 30 extends radially along a row of radially arranged feeder positions 20 .

[0041] In normal operation, the collection frame 32 is rotated one-way in a collection direction C along the endless collection path Zl so that each collection hopper 30 can make a full revolution of three-hundred-and-sixty degrees , about the rotation axis X and visit all feeder positions 20 of the array of feeder positions 20 , though in some embodiments the rotational movement could be more limited .

[0042] The packaging section 6 comprises a first packaging unit 61 at a first packing position or a first angular packing position Pl about the rotation axis X . Optionally, the packaging section 6 may comprise a second packaging unit 62 at a second packing position or a second angular packing position to increase the packing ef ficiency of the dispensing device 1 . The valves of the collection hoppers 30 are operated when a respective one of the collection hoppers 30 is in a position overhead or directly above a selected one of the packaging units 61 , 62 to drop the collected medicaments 90 into the respective packaging unit 61 , 62 . Each packaging unit 61 , 62 comprises a stock member for holding the packaging material , in this example a foil , a printer for printing information about the medicaments 90 on the foil , a filling member for positioning the foil to receive the medicaments 90 , a seal member for forming a pouch around the received medicaments 90 , a perforation member for providing the foil with perforations between subsequently formed pouches P and an output member for outputting the packaged medicaments from the dispensing device 10 .

[0043] Alternatively, one of the packaging units 61 , 62 or both may be arranged for packaging the medicaments 90 in a storage material other than a foil , e . g . in vials , bottles or cards .

[0044] The first packing position and / or the second packing position can be fixed relative to the rotation axis X, at least during the dispensing operation .

[0045] As shown in figure 1 , the dispensing device 10 is further provided with a control unit 7 that is operationally and / or electronically connected with the robotic arm 11 , the feeder units 40 , the packaging units 61 , 62 and other electronic equipment such as drives , sensors and the like, to control the operation of the dispensing device 10 . The control unit 7 comprises a special purpose processor 71 and a computer-readable medium 73 holding computer-readable code or instructions that , when executed by the processor 71 , cause the dispensing device 10 to operate according to the methods described in more detail hereafter . The computer-readable medium 73 is non-transitory or tangible , e . g . a physical data carrier such as a hard-drive , a USB-drive, a RAM memory or the like .

[0046] The dispensing device 10 may further be provided with a graphical user interface 8 , for example a screen, to provide a human operator with useful information about the dispensing, collection and packing operation, and for the human operator to enter or control the dispensing device 10 and / or parts of the dispensing device .

[0047] During operations , the dispensing device dispenses medicaments from feeder units 40 into collection hopper 30 , and after that to a packaging section where the medicaments are packaged . When a feeder unit 40 runs out of medicaments , robotic arm 11 must remove the empty feeder unit and either place it in a stock position 12 along housing 10 for storage or in drawer 25 for removal and refilling . Robotic arm 11 must then retrieve another feeder unit 40 to place in the now empty feeder position 20 .

[0048] Before normal operations ( as described above ) , the robotic arm 11 must be trained or calibrated to be able to precisely place and remove feeder units from all feeder positions 20 in the array of feeder positions , all stock positions 12 around housing 10 , as well as feeder loading positions 24 in drawer . These include complex movements in three-dimensional space , and in the embodiment shown, due to the cylindrical shape of housing 10 and particularly stock positions 12 , this will include subtle tilting which cannot be easily calculated or trained as would be in a fully planar grid .

[0049] Method 60 allows for a simple yet ef ficient process of calibrating robotic arm 11 with gripper 13 with respect to feeder positions 20 ( including stock positions 12 and loading positions 24 ) . Method 60 allows for such calibration in an ef ficient manner despite requiring precise movements with respect a large amount ( e . g . , 1000+ ) of feeder positions which may be angled and / or not ( all ) be in a planar or gridformation .

[0050] Method 60 starts with connecting a teach tool 70 to the dispensing device 10 , and particularly fixing an upper teach tool 72 to the robotic arm 11 , e . g . , to gripper 13 ( step 61 ) . This can be through a gripper connection part of the upper teach tool 72 , generally shaped like an upper part of a feeder unit which the robotic arm 11 will be carrying to and from feeder positions 20 . The connections of upper and lower teach tool parts 72 , 74 are shown in Fig . 4C . Upper teach tool 72 can be fixed to the robot arm mechanically, for example , by bolts and / or fixed by dowel pins , though other components or types of mechanical connections could be used .

[0051] Step 62 involves positioning a lower teach tool 74 in a first feeder position, arranging holes 81 to align with protrusions 83 of a feeder position 20 . This first feeder position is the first position to be taught and typically is a specific position which would be indicated by the controller, for example , on a user interface . This could be, for example , a corner position or other set position for the robotic arm 11 to begin recording set positions . The connections or mounting of lower teach tool 74 can be done simply by gravity and the alignment of protrusions through holes 81 . Using only gravity and not otherwise fixing lower teach tool 74 can help in ef ficiency of the method as the lower teach tool 74 can be more quickly moved to a further position once one position has been taught .

[0052] Teach tool 70 can be seen in Figs . 4A-4C, showing schematic views in Figs . 4A-4B, and a perspective view of teach tool 70 with upper teach tool 72 and lower teach tool 74 aligned and in use in Fig . 4C .

[0053] Upper teach tool 72 comprises gripper connection part 76 ( for connecting to gripper 13 of robotic arm 11 ) and three pins 77a, 77b, 77c extending substantially perpendicularly from gripper connection part 76 . Gripper connection part 76 can be substantially similar to that of a top of a feeder unit 40 , which robotic arm 11 will be moving during operations .

[0054] Lower teach tool 74 comprises a feeder unit connection part 78 and three pins 79a, 79b, 79c extending substantially perpendicularly from planar upper surface 75 of gripper connection part 76 , and holes 81 for connection to feeder unit docks ( see Fig . 4C, showing the feeder unit dock protrusions 83 extending through holes 81 ) . The three pins 77a, 77b, 77c of upper teach tool 72 are arranged on gripper connection part 76 to be able to be aligned with the three pins 79a, 79b, 79c of lower teach tool 74 during a calibration process. In the embodiment shown, each set of pins are arranged in a L or triangle shape, though other embodiments could have a different arrangement. Teach tool parts 72, 74 are typically metallic, for example, steel, though could be formed of other materials in other embodiments (e.g., other metals, plastic, composites) . In some embodiments, teach tool 70 could include one or more sensors (e.g., position sensor, a 3D touch probe) . Embodiments that include a sensor or probe could facilitate more automation of the teaching process, relying on sensing the correct positioning of teach tool parts 72, 72.

[0055] Coming back to method 60, once upper and lower teach tools 72, 74 are secured in place; calibration to the position in which lower teach tool 74 has been placed (here, first feeder position) can begin. This starts with step 63, automatically moving robotic arm 11 to the vicinity of the first feeder position (where lower teach tool 74 is positioned) . This could be, for example, 5 mm -50 mm away from the position, 5 mm - 25 mm away, or 10 mm from the first position .

[0056] Next, in step 64, the robotic arm is manually adjusted such that the three pins 77a, 77b, 77c of upper teach tool 72 are aligned with the three pins 79a, 79b, 79c of lower teach tool 74. This can be done by an operator, for example, prompted by an instruction by the controller which is displayed on user interface 8. This can in some embodiments also include leveling the gripper 13 on the robotic arm 11, and in some cases could involve the use of a spirit level or other leveling device. Leveling can be especially important for the (substantially planar) array of feeder positions 20.

[0057] Next, in step 65, the coordinates of the robotic arm 11 are recorded once it is confirmed that pins 77a, 77b, 77c and 79a, 79b, 79c are aligned. This could be automatic, for example, through one or more sensors (e.g., a 3D touch probe) confirming alignment, or through an operator manually confirming alignment, e.g., through a command or confirmation by the operator on a user interface.

[0058] In step 66, after coordinates have been recorded, robotic arm 11 moves away or retracts from the first feeder position, for example, 10-100 mm, or about 25-75 mm away, for example, 50 mm. The movement direction is generally perpendicular to the planar surface 75 of lower teach tool part 74. Thus, when teaching positions around the array of feeder positions 20 (which are generally in a planar orientation around robot (11) , the movement will be upwards. However, when teaching positions which are not oriented vertically, for example, a stock position 12, the movement would be at an angle.

[0059] Next, steps 62-66 are repeated for X number of further feeder unit positions. The specific number of times these steps need to be repeated depend on a number of factors, including but not limited to the configuration of feeder unit positions 20, stock positions 12, loading position 24, the housing 10 configuration, any other obstacles in the dispensing unit, etc. Typically, and in the example embodiment shown, this would require teaching around 2% - 75% of the total possible feeder positions, for example, 3%-50%, 4% to 30% or about 5% to 10% of the total feeder positions. In an example, 12 positions are taught and then 410 can be calculated with the taught positions. Thus, tremendous amounts of teaching time can be saved with respect to past systems where each individual position needed to be taught .

[0060] After the teaching of a sufficient number of positions, the coordinates for the remaining or non-taught positions can be determined in step 67. This can be through calculating the geometrical positions, enabled by the three- pin teaching tool 70. For example, using known absolute positions from the specifications of device 10 (including feeder positions 20 and stock positions 12) , and the recorded actual positions from robot arm movement to the selected teaching positions ; a comparison can be made to account for any variances in absolute versus actual positioning . These would also take into account any inclinations . Thus , the variances of recorded / actual versus known positions , the known locations of all positions , and the select taught positions can all be used to determine the rest of the (untaught ) feeder positions 20 and stock positions 12 for proper robot arm 11 movement .

[0061] In the example shown, typically, the planar table of radial feeder positions 20 would be first taught , and then the stock positions 12 on the inside of the housing 10 . For example, a first position closest to the robotic arm in the center of the table , and a distal position radially aligned with the first position could be taught on the table . In some embodiments , one position on the radial line between the two would be taught as well . Similar positions could be taught at 90 , 180 and 270 degrees from the first position . All feeder positions 20 could then be calculated from teaching those 8 (or 12 ) positions . For the stock positions 12 , upper and lower positions could be taught in a number of radial sections around the housing 10 . For example , the housing could be split into 8 radial sections , and the corners as well as any obstacles ( e . g . , doors , drawers ) could be taught, with the rest of the positions calculated .

[0062] In past systems , each feeder position had to be individually taught to the robotic arm to ensure that the dispensing device worked properly and the robotic arm was able to access each individual feeder position for moving a feeder unit to or from that position when needed . This required large amounts of time and man-power for teaching systems with large amounts of feeder positions , such as the system shown in Fig . 1 , which has more than 1000 feeder positions . Other past systems also worked with calibrating the robot without a teach tool , and instead with the robotic parts to be used in operations . Such calibration methods can risk damaging robotic parts during the process , and typically require teaching many more positions than the teach tool shown and described herein.

[0063] Method 60 allows for larger and more complex dispensing systems (which can hold larger amounts of feeder units 40 and therefore continuously dispense more amounts and types of medicaments) by providing calibration methods and devices to enable robotic arm 11 to accurately and efficiently learn complex coordinates of all possible feeder unit positions 20, 12 without needing to be taught each position. The use of teach tool 70, with upper teach tool 72 to be mechanically fixed to the robotic arm and lower teach tool 74 to be connected to a feeder position also help to ensure that many fewer positions need to be specifically taught than in past systems. Thus, method 60 offers high precision and simplifies the calibration process by teaching a limited number of positions with a combination of automatic and manual movements using teach tool 70, and using these recorded (i.e., taught) positions to determine the remaining positions in an accurate and efficient manner. Such methods also do not require complex laser sensors or cameras for visual recognition that past systems required.

[0064] Fig. 5 shows a method 80 for performing a check of the calibration method 60 shown in Fig. 3, and specifically performing a check of one or more of the positions taught and recorded in steps 62-66. Method 80 also uses teach tool 70, connected and used in the same manner as discussed with respect to method 60. Such a method can be used, for example, when a regular test of the workings of dispensing device 10 (and particularly robot arm 11 movement) does not go smoothly and / or when operations are not going smoothly (e.g., the robotic arm 11 does not place a feeder unit 40 properly) . In such a situation, method 80 can be used for checking the calibration of one or more positions.

[0065] In step 82, the robotic arm 11 is instructed to move to a particular position, for example, one of the positions taught in method 60. The instructions can be given, for example, on user interface 8 or on a separate user interface (e.g., connected directly to the robot) , and in some embodiments , the system could be set to a check mode for this process . Next , in step 84 , the robotic arm 11 is automatically moved to near the particular position . This could be , for example , within 10 mm -100 mm from the recorded position, for example , 50 mm from the recorded position .

[0066] In step 86 , permission to proceed to the particular position is requested . This is typically done while the robotic arm 11 is stopped at the position near the particular position after the automatic movement in step 84 . The permission can be requested through, for example, user interface 8 , and the operator is requested to visually inspect whether the robotic arm 11 is near the particular position and whether it should proceed to the particular position . This means that the operator visually inspects whether the robotic arm 11 is in the expected position and has to confirm with a yes or a no . This confirmation can be on user interface 8 or a separate user interface connected directly to the robot .

[0067] I f the operator confirms with a yes , step 88 is performed, and robotic arm 11 automatically moves to the particular position . In some embodiments , the operator could also manually fine-tune the position at this point and update the recorded position ( that was originally recorded in step 66 ) . I f the operator sees that the robotic arm 11 is not in the expected location after step 84 , the operator tells the system no , or not to proceed . In that case , step 90 is performed to re-teach the intended position - performing steps 62- 66 of method 60 with respect to the particular position .

[0068] Method 80 for performing a check of the calibration method 60 could be done after teaching a certain number of positions in steps 62- 66 of method 60 , could be performed after teaching each intended position, or only after a normal test or actual operations indicate that calibration may be of f ( e . g . , feeder units 40 are not being placed or picked up properly) . In some cases , method 80 would or could be performed after step 67 of determining all positions , and in other cases at least some amount of taught ( and recorded positions ) would be checked with the method before determining all other positions in step 67 . That can ensure an ef ficient calibration system whereby non-taught positions don' t need to be re-determined when it is found that one or more taught positions need to be re-taught .

[0069] In summary, the methods 60 , 80 and teaching tool 70 provide an ef ficient and accurate way of calibrating a robotic arm to work in three-dimensional space without having to individually teach each position . By having teaching tool 70 with upper and lower parts 72 , 74 , each with three pins , accurate three-dimensional alignment can be made and recorded, even in complex geometry such as tilted feeder units and / or in a cylindrically shaped housing around the robotic arm 11 . Teach tool 70 therefore allows for ef ficient and ef fective calibration while protecting robotic parts during the calibration process . Method 60 for calibration allows for precisely teaching a set number of positions , using a combination of automatic and manual steps to ensure ef ficient and accurate teaching; and then using that set number of positions to determine the remaining . Thus , not all positions need to be individually taught , saving time in calibrating devices with a large number of feeder positions . Method 80 helps to easily and ef ficiently check the accuracy of the initial teaching and re-teach if necessary .

[0070] While the description refers to medicaments , tablets , etc . , the devices and methods could be used for dispensing other types of solid discrete items for separation and packaging .

[0071] It is to be understood that the above description is included to illustrate the operation of the embodiments and is not meant to limit the scope of the invention . From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the spirit and scope of the present invention .

Claims

C L A I M S1. A method for calibrating a robotic arm (11) with respect to a plurality of feeder positions in three- dimensional space, the method comprising: i. fixing, by mechanical means, an upper teach tool (72) to the robotic arm; ii. positioning a lower teach tool in a first feeder position; iii. automatically moving the robotic arm to the vicinity of the first feeder position; iv. manually adjusting the robotic arm position such that the upper teach tool aligns with the lower teach tool at the first feeder position; v. recording the coordinates of the robotic arm for the first feeder position; vi . repeating steps ii - v for a set number of further feeder positions; and vii. determining coordinates for all feeder positions of the plurality of feeder positions based on the recorded coordinates of the first feeder position and the further feeder positions.

2. The method of claim 1, wherein the upper teach tool and the lower teach tool each comprise three pins.

3. The method of any of the preceding claims, wherein the set number of further feeder positions is 2-30% of the plurality of feeder positions.

4. The method of any of the preceding claims, and further comprising, as part of step iv., leveling a gripper on the robotic arm.

5. The method of any of the preceding claims, wherein step iii. comprises automatically moving the robotic arm to within 50 mm of the first feeder position.

6. The method of any of the preceding claims , wherein step v . further comprises , after recording the coordinates of the robotic arm for the feeder position, moving 10-100 mm away from the feeder position .7 . The method of claim 6, wherein the movement 10- 100 mm away from the feeder position is in a perpendicular direction to the planar surface ( 75 ) of the teach tool lower part ( 74 ) .8 . The method of any of the preceding claims , and further comprising : viii . perform a check of one or more recorded positions .

9. The method of claim 8 , wherein step viii . comprises : instructing the robotic arm to move to a particular position in a check mode ; automatically moving the robotic arm to near the particular position; requesting confirmation to proceed to the particular position; and if the confirmation to proceed is given, moving the robotic arm to the particular position; or if the confirmation to proceed is denied, optionally perform steps iv . - v . at the particular position .10 . The method of any of the preceding claims , wherein the plurality of feeder positions extends around a central axis , preferably wherein the robotic arm is located at or near the central axis .11 . The method of claim 10 , wherein the plurality of feeder positions extends in a first plane around the central axis and on an inner side of a housing surrounding the robotic arm.

12. The method of claim 11, wherein the housing is substantially cylindrical in shape.

13. The method of any of the preceding claims, wherein the plurality of feeder positions are in a dispensing device for dispensing discrete medicaments.

14. A dispensing device for dispensing discrete medicaments, the dispensing device (10) comprising: a dispensing section (2) defining an array of feeder positions for holding a plurality of feeder units (40) , a collection section for receiving the medicaments from the dispensing section, a robotic arm (11) ; and a control unit (7) for controlling the robotic arm, the control unit configured to perform the method of any of claims 1-13.

15. The dispensing device of claim 14, and further comprising a packaging section (6) for packaging the medicaments (90) received from the collection section.

16. The dispensing device of any of claims 14-15, and further comprising a housing surrounding at least part of the dispensing device.

17. The dispensing device of claim 16, wherein an inner side of the housing comprises one or more housing feeder positions extending along one or more walls of the housing as part of the plurality of feeder positions.

18. The dispensing device of any of claims 15-17, and further comprising one or more doors and / or drawers with one or more feeder positions in the one or more doors and / or drawers as part of the plurality of feeder positions.19 . The dispensing device of any of claims 15-18 , and further comprising one or more posts with one or more feeder positions on the one or more posts as part of the plurality of feeder positions .20 . A teaching tool for calibrating a robotic arm with respect to a plurality of feeder positions in three- dimensional space , the teaching tool comprising : an upper teach tool comprising a gripper connection part for connecting to the robotic arm and three pins extending substantially perpendicularly from the upper part ; and a lower teach tool comprising a feeder position connection part and three pins extending substantially perpendicularly from the feeder position connection part ; wherein the three pins of the upper teach tool are arranged on the gripper connection part to be able to be aligned with the three pins of the lower teach tool for teaching feeder positions .21 . The teaching tool of claim 20 , wherein the configuration of the three pins on the upper teach tool and the three pins on the lower teach tool are in a L or triangle shape .22 . The teach tool of any of claims 20-21 , wherein the teach tool comprises sensors .

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