CORRECTING MISPLACEMENTS ON A SORTER ELEMENT

Description

[0001] The invention relates to the technical field of correcting a misplacement of a piece of goods on a sorting element.

[0002] Shipments or other piece goods are sorted automatically by sorting devices. Typically, one piece of goods at a time is placed by induction or manually onto the receiving area of ​​a carrier or segment of a sorter. The sorter is designed to receive one piece of goods at a time on one of a plurality of receiving areas and transport each of the piece goods to any one of several sorting destinations. Typically, the sorter is a conveyor line that transports the carriers and thus the receiving areas to the sorting destinations arranged along the conveyor line. The carriers usually include a discharge mechanism, for example a cross belt or a tilting tray, from which the respective piece of goods is discharged directly from the respective receiving area to an automatically determined sorting destination.

[0003] If goods are located between two segments or receiving areas of a conventional sorter, they cannot be ejected in an orderly manner. In such a case, the sorter control system locks the segments for further use. Sorter capacity and throughput thus continue to decrease until the goods are removed. Incorrectly positioned goods can also occasionally become dislodged and fall from the sorter, which can pose a hazard to personnel.

[0004] Other sorting systems, for example, are based on a plurality of Automated Guided Vehicles (AGVs), where each AGV comprises a carrier with a receiving area and a drop mechanism. The AGVs can thus pick up piece goods from the receiving area, transport them individually to the sorting targets, and then drop the piece goods into the respective sorting targets. If a piece of goods rests on the frame of the AGV or is not sufficiently securely positioned on the receiving area, a similar problem arises as with conventional sorters.

[0005] In The problem described above is generally addressed by periodically clearing backed shipments and performing cleaning at the end of each shift. While such maintenance is labor-intensive, it does not prevent full capacity from being restored until after a maintenance cycle.

[0006] A loading control unit can also be used to detect whether segments are empty or occupied.

[0007] Another possibility is to use a blower to clear the sorter, especially of misplaced, lightweight mail. EP3566982A1 discloses a blower-based solution.

[0008] Several AGVs can also be coupled mechanically or virtually in series and thus transported to the sorting destinations in a similar way to a train composition, and thus comparable to a classic sorter.

[0009] Furthermore, EP3041615B1 discloses a method for feeding objects to a sorter from a stream of objects arriving at a feed conveyor.

[0010] EP 3 566 982 A1 protects a sorting device for sorting objects, comprising a conveyor movable in a conveying direction along a conveying path. WO 2018 / 200503 A1 protects a processing system with a singulation system for providing a singulated stream of objects.

[0011] The invention is based on the object of optimizing the throughput of a sorting system and increasing its operational reliability.

[0012] This solution to this problem is achieved by the concepts described in the independent claims.

[0013] According to one aspect, the invention relates to a method for correcting the misplacement of a piece of goods on a sorter element. The sorter element comprises a receiving area and is designed to receive the piece of goods in a receiving area, transport them to any one of several sorting destinations, and deliver them from the receiving area to the desired sorting destination. According to the method, a piece of goods is placed on the sorter element. A data structure representing a placement of the piece of goods on the sorter element is automatically recorded. Misplacement of the piece of goods on the sorter element is automatically detected based on the data structure. A robot is controlled such that the misplacement of the piece of goods on the sorter element is corrected by the robot.

[0014] According to a further aspect, the invention relates to a system for correcting the misplacement of a piece of goods on a sorting element. The system comprises a robot and a detection device. The detection device comprises a sensor system and a control device and is configured to detect a data structure representing the placement of the piece of goods on the sorting element and to detect a misplacement of the piece of goods on the sorting element based on the data structure. The control device is configured to control the robot so that it corrects the misplacement of the piece of goods on the sorting element.

[0015] Advantages and embodiments of the invention, which can be used individually or in combination with one another, are the subject of the dependent claims.

[0016] The data structure can, for example, comprise a digital image of the piece goods and / or of at least parts of the sorting element.

[0017] The sorting element can, for example, comprise a sorter or part of a sorter. The sorting element can also be designed as an AGV or a combination of several AGVs.

[0018] The robot can be designed exclusively or primarily to correct misplacements. Alternatively, the robot can be assigned to correct misplacements on the sorter element as a secondary task, while performing another primary task, such as loading the sorter element with piece goods.

[0019] According to one embodiment, the robot corrects the misallocation by picking up the piece goods and transferring them to a subsequent free pick-up area of ​​the sorter element, for example to a subsequent free pick-up area of ​​a sorter or to the pick-up area of ​​a subsequent AGV.

[0020] According to one embodiment, the misplacement includes the item not being placed or not being completely placed in the receiving area. For example, the control device can be configured to determine, based on the data structure, whether the item was not placed or not being completely placed in the receiving area of ​​the sorting element.

[0021] This allows a cause that particularly frequently leads to a reduction in the throughput of sorting systems to be automatically identified.

[0022] According to one embodiment, the misplacement includes the item not being placed or not being placed completely in the receiving area. This can prevent the item from falling sideways off the sorting element or colliding with a person or device positioned along a conveyor path along which the sorting element conveys the item.

[0023] According to one embodiment, the misplacement involves the receiving area being intended to receive only a single piece of goods, but being occupied by two or more pieces of goods. This can further increase the reliability and throughput of the sorting process. For example, it can also prevent two pieces of goods from such a double occupancy with different destinations from being diverted to the same sorting destination, which would result in one of the pieces of goods being sorted incorrectly.

[0024] According to one embodiment, the incorrect placement of the piece goods causes the piece goods to interfere with the sorter element's regular discharge mechanism due to jamming or sticking. This allows the receiving area to be cleared for further shipments.

[0025] According to one embodiment, the misplacement involves the item projecting laterally beyond the sorting element in a conveying direction of the sorting element. This can increase operational reliability and throughput.

[0026] According to one embodiment, the misplacement involves the item exceeding a size intended for the sorting element. This can increase operational reliability and throughput.

[0027] According to one embodiment, the misplacement involves the piece goods being waste or fragments of the piece goods being transported. This can increase operational reliability and throughput.

[0028] According to one embodiment, the misplacement is corrected by moving the piece goods into the receiving area using the robot. For example, the control device can be configured to control the robot so that it corrects the misplacement of the piece goods on the sorting element by moving the piece goods into the receiving area. This has the advantage that the piece goods can then be processed by the sorting element without further infeed, which has a positive effect on throughput.

[0029] According to one embodiment, the control device checks the data structure for criteria, and based on the checked criteria, the control device selects a method by which the misplacement is corrected. This allows for a flexible correction of the misplacement, adapted to the respective type of misplacement and / or type of piece goods.

[0030] For example, the method can be selected from any selection of at least two of the following methods: a) Correcting the misplacement by means of the robot; b) Moving the piece goods into the receiving area by means of the robot; c) Ejecting the piece goods from the sorter element by means of the robot; d) Ejecting the piece goods by means of a discharge mechanism of the sorter element (e.g. discharge by means of a tilting tray or a crossbelt movement); e) Combining placement of the piece goods by means of the robot with discharge of the piece goods by means of a discharge mechanism of the sorter element; f) Signaling that the misplacement is to be corrected by human intervention.

[0031] According to one embodiment, the robot is stationary or movable independently of the sorting element. For example, the robot is not permanently mounted to the sorting element, or is not mounted in such a way that the robot would be transported together with piece goods by means of the sorting element. This allows for a simple robot design.

[0032] According to one embodiment, the robot is arranged above a conveying surface of the sorting element, so that the sorting element loaded with the piece goods can pass unhindered, at least if no misplacement of the piece goods on the sorting element has been detected. If misplacement of the piece goods on the sorting element has been detected, the robot can correct the misplacement of the piece goods on the sorting element. This enables a simple design and arrangement of a robot, so that it can be moved as effectively as possible into all positions necessary to correct the misplacement of the piece goods on the sorting element.

[0033] According to one embodiment, the data structure also includes at least one piece of topography information of the piece goods, and the topography information is taken into account by the control device in order to control the robot in order to correct the incorrect placement of the piece goods on the sorting element.

[0034] According to one embodiment, the sorting element comprises a plurality of receiving areas, each of which is designed to receive a piece of goods, transport it to any one of a plurality of sorting destinations, and deliver it from the receiving area to one of the sorting destinations. For example, the sorting element is a sorter and comprises a plurality of receiving areas that, similar to a train composition, move in a conveying direction and are arranged in at least one linear row in the conveying direction.

[0035] According to further embodiments, the system may comprise multiple robots controlled by the control device or by further control devices such that the robots correct the misplacement of piece goods on sorting elements. According to further embodiments, the robots may be equipped with various manipulation tools, such as any selection of the following tools, to correct misplacement of piece goods: Gripper or pliers; vacuum suction cups (single suction cup, multiple suction cups); pusher; broom; blower.

[0036] Further features, characteristics, and advantages of the present invention will become apparent from the following description with reference to the accompanying figures, which schematically show: Figure 1 a system for correcting a misplacement of a piece of goods on a sorter element according to an embodiment; Figure 2a variant of a system for correcting a misplacement of a piece of goods on a sorter element according to an embodiment; Figure 3 a further variant of a system for correcting an incorrect placement of a piece of goods on a sorter element according to an embodiment.

[0037] The Figures 1 to 3 each show a system 1 designed as a sorting system according to various embodiments, which can, however, also be combined with each other. Figures 1-3 In order to better address the systems 3 shown, they are indexed with the letters a, b, c, i.e. systems 1a, 1b, 1c.

[0038] Figure 1shows a system 1a designed as a sorting system for correcting an incorrect placement 9 of piece goods 3 on a sorter element 2 designed as a sorter. The piece goods 3 are indexed with letters in the figures for better understanding and identification, i.e. 3a, 3b, 3c, 3d. The system 1a comprises the sorter 2, a detection device 6 and a robot 10 mounted next to and above the sorter 2. The detection device 6 comprises a sensor system 14 designed as a camera system and a control device 8. The camera system 14 is configured to capture a data structure 7 designed as image data, which represents a placement of the piece goods 3 on the sorter element 2. The control device 8 is configured to detect an incorrect placement 9 of the piece goods 3 on the sorter element 2 based on the data structure 7.The control device 8 is also designed to control the robot 10 based on the data structure 7 in such a way that it corrects the incorrect placement 9 of the piece goods 3 on the sorting element 2.

[0039] The sorter 2 is or comprises a conveyor line 2, which comprises a plurality of receiving areas 4 defined by cross-belt conveyors, which are indexed with the letters a to f for better understanding, i.e. 4a, 4b, 4c, 4d, 4e, 4f. Each of these receiving areas 4a, 4b, 4c, 4d, 4e, 4f comprises a cross-belt conveyor and is intended to preferably receive exactly one piece of goods 3 to be sorted.

[0040] In Figure 1It is evident that the piece goods 3b, 3d are at least partially placed between two adjacent receiving areas 4, and are therefore not positioned in such a way that the cross-belt conveyors can reliably discharge these piece goods 3b, 3d at a desired sorting destination. The piece goods 3b, 3d are therefore not completely placed in a receiving area 4 of the sorting element 2 and thus represent misplacements.

[0041] The camera 14 captures image data from each of the piece goods 3a, 3b, 3c, 3d conveyed in the conveying direction 19 and sends these as captured data structures 7 to the control device 8. The control device 8 evaluates the data structures 7 for each piece of goods 3 and checks them for criteria. Based on the checked criteria, the control device 8 decides whether or not a misplacement has occurred. In the Figure 1In the embodiment shown, the control device 8 controls the robot 10 to drop misplaced piece goods 3b, 3d into a container 21 by means of a method 91, while correctly placed piece goods 3a, 3b are transported further in the conveying direction 19 by the sorter 2 (not shown) and are discharged by means of the cross belts when they reach a suitable sorting destination.

[0042] The criteria can even be designed so that the control device 8 selects a method by which the misplacement 9 is corrected. Possible methods can include, for example: a) Correcting the misplacement 9 by means of the robot 10; b) Moving the piece goods 3 by means of the robot 10 into the receiving area 4; c) Ejecting the piece goods 3 from the sorter element 2 by means of the robot 10; d) Ejecting the piece goods 3 by a discharge mechanism of the sorter element 2; e) Combining placement of the piece goods 3 by means of the robot 10 with discharge of the piece goods 3 by a discharge mechanism of the sorter element 2; f) Signaling that the misplacement 9 is to be corrected by human intervention; g) No correction of a misplacement.

[0043] Figure 2 shows a variant of the Figure 1 illustrated embodiments, wherein the system 1b of Figure 2differs from system 1 in that a misplacement 9 is remedied by moving the piece goods 3 into the receiving area 4 by means of the robot 10. The control device 9 can be set up so that each of the misplaced piece goods 3 is moved into a free receiving area 4. Alternatively, the control device 8 can also decide individually for each misplaced piece goods 3 based on criteria whether this method 92 or another method, for example method 91, is used.

[0044] Preferably, topographic information of the piece goods 3 is also determined from the image data of the data structure 7, which is taken into account by the control device 8 in order to control the robot 10. In this way, an incorrect placement of the piece goods 3 on the sorter element 2 can be corrected more precisely.

[0045] In Figure 3 are in contrast to Figure 1Misplaced piece goods 3b, 3d are thrown out of the sorter 2 laterally via a chute 22 by means of a method 93, which has the advantage of more gentle handling of the piece goods.

[0046] Further advantageous embodiments can be implemented as follows: According to one embodiment, the detection device is designed as an optical detection system and monitors the placement of all shipments on the sorter and measures their exact positions. The optical detection system can comprise sensors and / or cameras and generate two-dimensional or three-dimensional representations of the monitored area.

[0047] According to one embodiment, incorrect assignments are detected based on defined criteria. The criteria can also be learned using sample images. If necessary, the criteria can also include a targeted evaluation of segments blocked by the sorter control.

[0048] According to one embodiment, the control device 8 determines a decision as to which method is likely to correct the misallocation: Robot; Discharge using conventional method (tilt tray, crossbelt movement); combination of robot arm with conventional discharge mechanism; only possible through human interaction; no misallocation detectable.

[0049] According to one embodiment, the robot is notified of incorrect assignments by the detection system on the belt, which can include: Shipment type (material, size, shape); Exact position; Possible gripping or manipulation point as 3D coordinate with surface normal vector; Drop-off point (chute, container, correct position on sorter segment).

[0050] According to one embodiment, the robot 10 is mounted above the sorter 2 and the cross belts or tilting trays in such a way that it does not interfere with the normal operation of the sorter 2, but can reach all relevant positions.

[0051] According to further embodiments, various robot kinematics are conceivable (kick arm, swivel arm, delta arm) depending on the sorter and shipment range. For example, the robot can be designed as a gantry robot.

[0052] According to further embodiments, the robot arm can be equipped with various tools: Gripper or pliers; vacuum suction cups (single suction cup, multiple suction cups); pusher; broom; blower.

[0053] According to further embodiments, the system 1 is designed such that if the robot only has to move a piece of goods 3 slightly, the incorrect placement can be remedied with the usual regular discharge method by means of a cross belt or a tilting tray of the conveyor 2.

[0054] According to further embodiments, the robot is so fast that it can operate at 2.5 to 4.0 m / s during sorting operations.

[0055] According to further embodiments, a slower operating mode is necessary.

[0056] According to further embodiments, the detection device 6 can estimate from an estimated time for correcting the incorrect allocations when a maintenance run is worthwhile in order to restore the full capacity of the sorter.

[0057] According to further embodiments, the detection device 6 can check the success of a rectification attempt after exactly one sorter cycle and, if necessary, repeat the rectification of the misplacement using the same or a different method.

[0058] According to further embodiments, the system can support manual sorter maintenance if remaining misallocations that can only be corrected by human interaction are successively sent directly to the service personnel.

[0059] According to further embodiments, the robot can also be equipped with brushes or other manipulators for automatically cleaning the sorting element 2, or tilting trays or cross belts.

[0060] According to further embodiments, not only misplaced piece goods but also packaging fragments, package contents and other unwanted objects can be removed.

[0061] According to further embodiments, even correctly placed items that cannot be removed using the usual drop mechanism for other reasons (stuck, drop mechanism defective, shipment rolling or too slow for the mechanism) can be removed.

[0062] According to further embodiments, the detection device 8 comprises an intelligent detection system for identifying, measuring and evaluating incorrect assignments with a memory for repeated rectification attempts and / or an interface to the sorter control.

[0063] Further advantages and implementation examples result from any selection of the following concepts: Precise manipulation does not require the sorter to be completely empty and can be carried out at full / reduced speed during operation; Less / no personnel expenditure; Faster sorter maintenance, can be carried out several times a day if necessary; Reduction of sorter malfunctions and personal hazards; Increase in sorter throughput; Detection system replaces the previous load control camera; Existing load control function can be expanded to include additional features (exact location of shipments, statistics, contamination detection); Heavy shipments cannot be removed with the blowers used to date; Removing heavy shipments is very unergonomic and potentially dangerous work; By regularly and specifically removing misplaced shipments, they can be returned to the sorting process more quickly, which leads to an increase in delivery quality and a shortening of delivery times; Less noise than with a blower alone.

[0064] Although the invention has been illustrated and described in detail by means of preferred embodiments, the invention is not limited by the disclosed examples. Variations may be derived by those skilled in the art without departing from the scope of the invention as defined by the following claims.

Claims

1. Method for correcting a misplacement (9) of a piece good (3) on a sorter element (2), comprising the method steps: - Placing the piece good (3) on the sorter element (2), wherein the sorter element (2) comprises a receiving area (4) and is designed to receive the piece good (3) in the receiving area (4), to transport them to any one of a plurality of sorting destinations and to discharge them there from the receiving area (4) to any sorting destination; - Automatic acquisition of a data structure (7) which represents a placement of the piece good (3) on the sorter element (2); - Automatic detection of a misplacement (9) of the piece good on the sorter element (2) by means of the data structure (7); characterized in that the method comprises - Controlling a robot (10) so that the robot (10) corrects the misplacement of the piece good (3) on the sorter element (2).

2. Method according to claim 1, wherein the misplacement (9) is corrected by moving the piece good (3) into the receiving area (4) by means of the robot (10).

3. Method according to any of the preceding claims, wherein the misplacement (9) comprises that the piece good (3) was not or not completely placed in the receiving area (4) and / or that the receiving area (4) is only intended to receive a single piece good (3), but is occupied by two or more piece goods (3) and / or that the misplacement of the piece good (3) causes that the piece good (3) obstructs a regular ejection mechanism of the sorter element (2) due to jamming or sticking and / or that the piece good (3) protrudes laterally beyond the sorter element (2) with respect to a conveying direction (19) of the sorter element (2) and / or that the piece good (3) exceed a size intended for the sorter element (2) and / or that the piece good (3) is waste.

4. Method according to any of the preceding claims, wherein the data structure (7) is automatically checked for criteria, and a method is automatically selected on the basis of the checked criteria, by means of which the misplacement (9) is corrected; wherein the method is preferably selected automatically from any selection of the following methods comprising at least two methods: a) Correcting the misplacement (9) by means of the robot (10); b) Moving the piece good (3) into the receiving area (4) by means of the robot (10); c) Ejection of the piece good (3) from the sorter element (2) by means of the robot (10); d) Ejection of the piece good (3) by a discharge mechanism of the sorter element (2); e) Combination of placement of the piece good (3) by means of the robot (10) with discharge of the piece good (3) by a discharge mechanism of the sorter element (2); f) Signalizing that the misplacement (9) is to be corrected by human intervention; g) No misallocation recognizable.

5. Method according to any one of the preceding claims, wherein the robot (10) is stationary or movable independently of the sorter element (2).

6. Method according to any of the preceding claims, wherein the robot (10) is arranged above a conveying surface of the sorter element (2), so that the sorter element (2) loaded with the piece good (3) can pass the robot unhindered at least when no misplacement of the piece good on the sorter element (2) has been detected, and that the robot (10) can correct the misplacement (9) of the piece good (3) on the sorter element (2) if a misplacement (9) of the piece good (3) on the sorter element (2) has been detected.

7. Method according to any of the preceding claims, wherein the data structure (7) also comprises a topography information of the piece good (3), and the topography information is taken into account to control the robot to correct the misplacement of the piece good (3) on the sorter element (2).

8. System (1) for correcting a misplacement (9) of a piece good (3) on a sorter element (2), comprising a detection device (6); wherein the detection device (6) comprises a sensor system (14) and a control device (8) and is set up to detect a data structure (7) which represents a placement of the piece good (3) on the sorter element (2) and to recognize a misplacement (9) of the piece good (3) on the sorter element (2) on the basis of the data structure (7); characterized in that the system comprises a robot (10) and the control device (8) is designed to control the robot (10) in such a way that it corrects the misplacement (9) of the piece good (3) on the sorter element (2).

9. System (1) according to claim 8, wherein the control device (8) is set up to determine, on the basis of the data structure (7), whether the piece good (3) has not been placed or has not been placed completely in a receiving area (4) of the sorter element (2) and / or whether the receiving area (4) is intended only for receiving a single piece good (3) but is occupied by two or more piece goods (3) and / or whether the misplacement of the piece good (3) causes that the piece good (3) obstructs a regular ejection mechanism of the sorter element (2) due to jamming or sticking and / or whether the piece good protrudes laterally beyond the sorter element (2) with respect to a conveying direction (19) of the sorter element (2) and / or whether the piece good (3) exceeds a size intended for the sorter element (2) and / or whether the piece good (3) is waste.

10. System (1) according to claim 9, wherein the control device (8) is designed to control the robot (10) in such a way that it corrects the misplacement (9) of the piece good (3) on the sorter element (2) by moving the piece good (3) into the receiving area (4).

11. System (1) according to any one of claims 8 to 10, wherein the control device (8) is designed to check the data structure (7) for criteria, and to select a method by means of which the misplacement (9) is corrected, based on the checked criteria; wherein the control device (8) is preferably designed to select the method from any selection of the following methods comprising at least two methods: a) Correcting the misplacement (9) by means of the robot (10); b) Moving the piece good (3) into the receiving area (4) by means of the robot (10); c) Ejection of the piece good (3) from the sorter element (2) by means of the robot (10); d) Ejection of the piece good (3) by a discharge mechanism of the sorter element (2); e) Combination of placement of the piece good (3) by means of the robot (10) with discharge of the piece good (3) by a discharge mechanism of the sorter element (2); f) Signalizing that the misplacement (9) is to be corrected by human intervention; g) No misallocation recognizable.

12. System (1) according to any one of claims 8 to 11, wherein the robot (10) is stationary or movable independently of the sorter element (2).

13. System (1) according to any one of claims 8 to 12, wherein the robot (10) is arranged above a conveying surface of the sorter element (2) in such a way that the sorter element (2) loaded with the piece good (3) can pass the robot unhindered at least when no misplacement of the piece good (3) on the sorter element (2) has been detected, and the robot (10) can correct the misplacement (9) of the piece good (3) on the sorter element (2) when a misplacement (9) of the piece good (3) on the sorter element (2) has been detected.

14. System (1) according to any one of claims 8 to 13, wherein the detection device (6) is set up to detect at least one topography information of the piece good (3), wherein the control device (8) takes the at least one topography information into account in order to control the robot (10) in order to correct the misplacement of the piece good (3) on the sorter element (2).

15. System (1) according to any one of claims 8 to 14, wherein the sorter element (2) comprises a plurality of receiving areas (4), each of which is intended to receive a piece good (3) and to deliver it to one of the sorting destinations.