AU2010235933A1 - Robotic Layer Picker System - Google Patents

Description

P/00/009 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Invention Title: ROBOTIC LAYER PICKER SYSTEM The invention is described in the following statement together with the best method of performing it known to us: Our Ref: 102022 - 2 ROBOTIC LAYER PICKER SYSTEM The present invention relates to product distribution centres and, more particularly, to at least the partial automation of such centres. 5 BACKGROUND Products for distribution to retail outlets are typically organised for transport at centralised distribution centres (DCs) . Palletised product is received 10 in these centres from manufacturers, importers and growers and must be broken into smaller quantities according to orders placed on the DC by the various retail outlets serviced by it. Typically, the breaking up of product stacked on 15 received pallets for re-stacking onto delivery pallets is done either manually, or may be done in a semi-automated process using suitably equipped forklift trucks which may lift layers from a supply pallet and place the layer on a delivery pallet, Either process is time consuming and 20 vulnerable to human error. It is an object of the present invention to address or at least ameliorate some of the above disadvantages. 25 -3 Notes 1. The term "comprising" (and grammatical variations thereof) is used in this specification in the inclusive sense of "having" or "including", and not in the 5 exclusive sense of "consisting only of". 2. The above discussion of the prior art in the Background of the invention, is not an admission that any information discussed therein is citable prior art or part of the common general knowledge of persons skilled 10 in the art in any country. BRIEF DESCRIPTION OF INVENTION Accordingly, in a first broad form of the invention, there is provided a robotic layer picker system for palletized product management in a product distribution centre; said 15 picker including a traveling robot along at least one line of pallet feeding conveyors; said traveling robot equipped with at least one pallet loading station coupled to said robot; said pallet feeding conveyors feeding received pallets of layered products to a picking position adjacent 20 to a line of travel of said robot; said robot picking an uppermost layer of product from selected ones of said received pallets of product at said picking position; layers picked from said received pallets of product placed by said robot on a delivery pallet on said at least one 25 pallet loading station; said at least one delivery pallet - 4 placed by said robot onto a discharge conveyor for transport. Preferably, said robot is under control of on-board layer picking software. 5 Preferably, layers of product are selected and picked from said received pallets according to orders for product received by controlling software of said system. Preferably, said traveling robot operates on a track between two rows of said feeding conveyors. 10 Preferably, each of said feeding conveyors moves received pallets of a product from an outer end of a said feeding conveyor to a picking position when said picking position is empty. Preferably, a fresh received pallet of product is placed on 15 an outer end of a said feeding conveyor when a said received pallet has been moved to said picking position. Preferably, said robot removes empty pallets from said picking position; said empty pallets placed on buffer stacks of empty pallets. 20 Preferably, pallets on said at least one pallet loading station of said robot which are full or which support a completed product order, are discharged from said loading stations onto discharge conveyors. In another broad form of the invention, there is provided a 25 method of assembling on a pallet a selection of layers of - 5 different product from pallets of homogeneous product arranged in layers; said method including the steps of: (a) arranging said pallets of homogeneous product in picking positions for accessing by a pick and place 5 robot, (b) driving said robot to a picking position of a pallet of homogeneous product required for said selection, (c) picking and placing one or more layers from said pallet of homogeneous product, 10 (d) placing said one or more layers on a pallet carried on a load station of said robot, (e) driving said robot sequentially to a picking position of each of said pallets of homogeneous product and adding layers for said selection. 15 BRIEF DESCRIPTION OF DRAWINGS Embodiments of the present invention will now be described with reference to the accompanying drawings wherein: 20 Figure 1 is a plan view of a preferred embodiment of a robotic layer picker system according to the invention, Figure 2 is an end view of a travelling robot and rows of palletized product feeding conveyors of the system of Figure 1. 25 DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS - 6 The present invention includes apparatus and process for the management of palletized product received in a central distribution centre (DC) . The invention provides for the removal of layers of product from selected ones of 5 a plurality of received pallets according to orders placed on the DC by retail outlets serviced by the centre. Central to the present system 10 shown in Figures 1 and 2, is a travelling pick and place robot 12 under the control of on-board layer picking software (LPS). The robot 10 12 is arranged for travel along a track 14, in this instance, between two rows 16 and 18 of feeding conveyors 20. In the exemplary layout of Figure 1 there are two rows of 10 feeding conveyors 20 each, but it will be understood that the number of feeding conveyors may be configured 15 according to the number of different products to be distributed. The travelling robot 12 is equipped with at least one, in this instance two, loading stations 22 and 24 running on the track 14 and coupled to the robot's platform 20 26. Each loading station includes a load platform of driven rollers (not visible in the drawings) . The robot arm 28 is equipped with suitable grippers and vacuum pads 30 as appropriate, to allow it to grasp and lift one complete layer 32 of product from a received pallet 34 stacked with 25 layers 32 of product. As well, the gripper assembly of the robot arm is adapted to lift pallets.

- 7 At one end of the rows 16 and 18 of feeding conveyors 20 are located one or two stacks 36 of empty pallets from which the robot 12 may place (and replace as required) two empty pallets, one on each of its loading stations 22 and 5 24. At the opposite end of the rows of feeding conveyors, are located a pair of mixed pallet discharge conveyors 38 and 40 extending from either side of the track 14 with the pair spaced apart equal to the spacing between the two 10 loading stations 22 and 24 of the robot 12. This allows for simultaneous discharge, by means of the load stations 22 and 24 driven rollers, of a pair of completed delivery pallets 42 from the load stations onto the discharge conveyors 38 and 40. Further buffer stacks 36 of empty 15 pallets may also be provided between the two discharge conveyors. Full received pallets 34 of various products arranged in layers 32, are placed at the outer ends of the feeding conveyors 20. This may be done by means of forklifts (not 20 shown), the driver's of which are under instruction via radio communication with the controlling software of the system. Each feeding conveyor 20 moves a full received pallet 34 placed at the outer end to a picking position 44 at the inner end of the feeding conveyor adjacent to the 25 line of travel of the robot 12 along track 14, if the picking position 44 is empty. After a received pallet 34 - 8 has been moved to the picking position 44 end of a feeding conveyor20, the controlling software orders an available forklift to replenish the feeding conveyor 20. The controlling software of the system receives orders 5 for product from retail- outlets or other mixed product destinations, Orders are accepted made up of layers of palletized product, so that an order may include a number of layers of selected different products, each of which is available at the distribution centre as pallets of 10 homogenous product. At the start of an operating cycle, the robot 12 ensures that its two loading stations 22 and 24 are prepared with fresh pallets, The layer pick software determines the location of the robot 12 and causes it to 15 drive to the nearest feeding conveyor 20 which has product required for the order to be processed. The robot 12 now picks and transfers to the pallet on the first of its loading stations 22, one or more layers 32 of the product required to satisfy that part of the order for that 20 product. The robot 12 is equipped to sense the weight of the layer 32 and the LPS can compare this with layer weight data received from the controlling software of the system to ensure that a complete layer 32 has been picked. Similar confirmation of correct lift may be provided by sensor 25 monitoring of the gripper mechanism and vacuum pads as appropriate.

- 9 The LPS now determines the location of the next nearest product required by the order and causes the robot 12 to travel to the appropriate pick up location 44, where it picks and places the required number of layers 32 onto 5 the layer/s of product already on the pallet on load station 22. This process is repeated until the pallet is full, or the order has been filled. If the order is larger than can be accommodated on a single pallet, the process continues with the picking and 10 placing of layers of product on the second loading station 24, but otherwise the robot's pick and place regime switches to a second order, layers of product for which are placed on the pallet of the second load station 24 of the robot, Each time the two load station pallets are either 15 full, or one or both support completed orders, the robot drives to a location between the two discharge conveyors 38 and 40 where the pallets are off-loaded. Continuously during the layer picking process, sensors monitor the status of the received pallets 34 on each of 20 the feeding conveyors 20, as well as the buffer stacks of pallets 36. Whenever a received pallet 34 at the picking position 44 end of a feeding conveyor 20 is empty of product and the robot is in the vicinity, it is ordered to remove the empty pallet and deliver it to the nearest of 25 the empty pallet stacks 36. Similarly, if there are no current orders in the controlling system for the product of - 10 a partially empty received pallet, that pallet is removed by the robot to special part pallet conveyors 46 at the end of the rows of feeding conveyors 16 and 18 opposite the discharge conveyors 38 and 40. 5 In at least one preferred arrangement, the system includes one, or a number of AGVs, (auto-guided vehicles) equipped with fork-lifting gear. These are also under the control of the controlling software of the system, so that when a received pallet is moved from the outer end of a 10 feeding conveyor to it picking position, an AVG is ordered to drive to a specified location in a nearby supply stack (not shown) of received pallets, retrieve the required replacement pallet and deliver it to the feeding conveyor. In Use 15 In use, it will be appreciated that the system of the present invention requires relatively little labour and substantially eliminates any manual labour required for assembling orders of product. With appropriate operating time data incorporated in the controlling system software, 20 the feeding conveyors can be kept resupplied in a timely manner, allowing the distribution centre to operate virtually around the clock, seven days a week. The above describes only some embodiments of the 25 present invention and modifications, obvious to those - 11 skilled in the art, can be made thereto without departing from the scope of the present invention.

Claims (9)

1. A robotic layer picker system for palletized product management in a product distribution centre; said picker including a traveling robot along at least one 5 line of pallet feeding conveyors; said traveling robot equipped with at least one pallet loading station coupled to said robot; said pallet feeding conveyors feeding received pallets of layered products to a picking position adjacent to a line of travel of said 10 robot; said robot picking an uppermost layer of product from selected ones of said received pallets of product at said picking position; layers picked from said received pallets of product placed by said robot on a delivery pallet on said at least one pallet 15 loading station; said at least one delivery pallet placed by said robot onto a discharge conveyor for transport.

2. The system of claim 1 wherein said robot is under control of on-board layer picking software. 20

3. The system of claim 1 or 2 wherein layers of product are selected and picked from said received pallets according to orders for product received by controlling software of said system.

4. The system of any one of claims 1 to 3 wherein said 25 traveling robot operates on a track between two rows of said feeding conveyors. - 13 s.

The system any one of claims 1 to 4 wherein each of said feeding conveyors moves received pallets of a product from an outer end of a said feeding conveyor to a picking position when said picking position is 5 empty.

6. The system of claim 5 wherein a fresh received pallet of product is placed on an outer end of a said feeding conveyor when a said received pallet has been moved to said picking position, 10

7, The system of claim 5 or 6 wherein said robot removes empty pallets from said picking position; said empty pallets placed on buffer stacks of empty pallets. o.

The system of any one of claims 1 to 7 wherein pallets on said at least one pallet loading station of said 15 robot which are full or which support a completed product order, are discharged from said loading stations onto discharge conveyors,

9. A method of assembling on a pallet a selection of layers of different product from pallets of 20 homogeneous product arranged in layers; said method including the steps of: (f) arranging said pallets of homogeneous product in picking positions for accessing by a pick and place robot, 25 (g) driving said robot to a picking position of a pallet of homogeneous product required for said selection, - 14 (h) picking and placing one or more layers from said pallet of homogeneous product, (i) placing said one or more layers on a pallet carried on a load station of said robot, 5 (j) driving said robot sequentially to a picking position of each of said pallets of homogeneous product and adding layers for said selection.