Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G61/00—Use of pick-up or transfer devices or of manipulators for stacking or de-stacking articles not otherwise provided for
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G2201/00—Indexing codes relating to handling devices, e.g. conveyors, characterised by the type of product or load being conveyed or handled
  • B65G2201/02—Articles
  • B65G2201/0235—Containers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G2203/00—Indexing code relating to control or detection of the articles or the load carriers during conveying
  • B65G2203/02—Control or detection
  • B65G2203/0208—Control or detection relating to the transported articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G2203/00—Indexing code relating to control or detection of the articles or the load carriers during conveying
  • B65G2203/04—Detection means
  • B65G2203/041—Camera

Definitions

• the invention relates to the field of large and medium-sized distribution logistics platforms and relates to a method and a system for palletizing items before delivery to a customer.
• Logistics platforms act as intermediaries between suppliers and different points of sale. Suppliers send their products to these platforms where they are received and processed for storage. Then, the outlets send their replenishment requests to these platforms. For each request, the requested products are taken out of stock to be sent to an order preparation area. In the preparation area, robots are used to place the products on shipping pallets which will then be transported to their destination.
• the first consists of a stack of interchangeable layers of the same Width/Length dimensions
• the second consists of a placement of layers with any dimensions placed without precise rules to follow. Due to the diversity of the articles to be placed, the first representation is too restrictive, because many objects cannot be found in a complete layer, for example of size 1200x800 mm, because of their small quantity. The quasi-optimal solutions obtained by the methods dedicated to this representation therefore place too few objects.
• the object of the invention is therefore to propose a system and a method of palletization making it possible to solve the problems of the methods described above, and making it possible to obtain arrangements of articles in layers on a container which are effective in terms of of placed items as well as stability.
• the invention relates, according to a first aspect, to a palletizing process in which:
• the articles are then loaded in several layers by a loading device onto a container arranged in the loading station, in which, the loading device being controlled by a computer control means, the method further comprises a step of generating a stable arrangement of said articles on the container upstream of their loading.
• said stable arrangement comprises a placement of articles having substantially close heights to form either complete layers occupying substantially the entire surface area of the container, or partial layers each occupying a part of the surface area of the container, and in which a first partial layer having a first layer height occupies a part of the container and at least one layer complementary partial having a second layer height occupies a second part not occupied by said first layer so as to occupy the entire surface of the container.
• the method according to the invention defines layers of articles to be placed which can be complete (able to occupy the entire surface of the container), or partial (able to occupy a part of the surface).
• the method according to the invention makes it possible to obtain efficient palletization in terms of the number of items placed and in terms of stability.
• the container can be any container used to palletize items for shipment, for example to a customer.
• this can be a pallet.
• a partial layer can occupy half the surface of a container (for example half the length and the entire width or vice versa), it can also occupy other proportions such as 1/3 or 1/4.
• this variant can be much more effective.
• This variant can be particularly interesting if there are many small objects with a very high diversity in height.
• two partial layers of substantially the same area can be superimposed. This makes it possible to fill a container, such as a pallet, by creating columns maximizing the volume occupied and stability.
• two partial layers are separated by a partial intermediate plate of substantially the same area as said partial layers.
• a partial intermediate plate of substantially the same area as said partial layers.
• the nature of the interlayer can make it possible to fill in the dispersions in height of the layer on which it is placed without while remaining rigid, which further increases stability.
• a partial layer and at least one complementary partial layer are placed on a complete layer.
• a complete intermediate plate can also separate the complete layer from the partial layers, said plate complete interlayer having substantially the same area as the container. This further increases stability.
• the method may comprise a step of generating a catalog of layers likely to be placed on the container, said catalog comprising at least one partial layer.
• the advantage of a catalog is that it defines the possible layers upstream of any layer construction and the process is restricted to using them in the most efficient way.
• the fact that the layer catalog also includes partial layers makes it easy to obtain article arrangements on a container (for example a pallet) that maximize the volume occupied as well as stability.
• the catalog can be gradually enriched by the addition of new possible layers having a strictly negative reduced cost, said reduced cost being deduced from the resolution of the following linear problem, the resolution being able to be made by known methods of the person skilled in the art (for example the simplex method):
• - z(C) is a value corresponding to the greatest profit of layers that it is possible to have by using a real number of layers of the catalog C.
• - p c is the profit of layer c, evaluated as the volume of objects in layer c plus a penalty proportional to the volume occupied by layer c in the container.
• This dynamic generation method uses the calculation formula above allowing, for a given set of layers, to assign to each object a value of interest. This value, positive or negative, is used to evaluate a layer that does not yet belong to the catalog. If said layer has a strictly negative reduced cost, then it is added to the set of layers contained in the catalog to improve the layered article arrangement that is obtained before palletization.
• Another advantage is that if there are no more layers that satisfy the above condition, then the set of layers allows to express an optimal solution. This property then makes it possible to know when to stop, but also using other formulas to determine a limit on the quality of an optimal solution.
• the reduced cost can be expressed by the formula:
• v c is the volume of the layer and has a real small enough that the profit of two layers is first evaluated according to the volume of the placed objects. For this same volume, the profit is compared on the volume that the occupied layer (We can also speak of "density" of the layer).
• the layers are chosen from the catalog which maximize the sum of the profits under the constraint that all the layers can be placed on the container without exceeding a limit height of the container fixed in upstream.
• a catalog C of layers c one can for example determine which ones to choose to constitute the solution by solving the following linear program (the methods of resolution being known for the specialists of operational research):
• the constraint h(A) ensures that it is possible to place the set of layers without any exceeding the fixed limit height, noted H.
• the method may include the use of a learning method to generate the layers given as parameters to the “integer linear program”. This allows an improvement when the objects to be palletized change little from one resolution to another.
• the computing means can comprise an internal memory, one thus safeguards the recurring layers which one transmits in parameter to the “linear program in whole numbers”.
• the method may include applying the method for a set of objects to be placed on more than one pallet.
• the distribution of objects must then be taken into consideration, their integration being facilitated by the notion of layers.
• the invention according to a second aspect also relates to a palletizing system implementing the method according to one of the combinations of characteristics described above.
• the palletizing system can include:
• a loading station that may include a reception area for a container and a loading device
• the loading device being controlled by computer control means configured to generate a stable arrangement of said articles on the container by putting implements the method as described above.
• Figure 1 shows an example of a palletizing system according to the invention
• Figure 2 is an illustration of a loaded pallet comprising full layers of items and half layers.
• Figure 1 shows an example of a palletizing system according to the invention.
• the system 1 comprises a conveying means 2 for transporting articles i to a loading station in order to load them onto an empty container 5 (pallet) arranged in the loading station.
• the conveying means 2 is a conveyor, but other conveying means can be used, in particular automatically guided robots (AMR/AGV).
• the palletization system 1 also comprises a loading means 4 for loading the articles i on the pallet 5.
• the loading means 4 is for example a multiaxial robot provided with a gripper 4a for grasping the articles i one by one and placing them on the pallet 5.
• the gripper 4a can have a grid as shown in the figure or have other known shapes, for example fitted with suction cups.
• the palletization system 1 can also comprise a means of detecting articles, for example a camera, arranged above the conveyor 2 in the vicinity of the loading station.
• the system 1 also comprises a control means, not shown, arranged to manage the loading of the articles by the loading means 4. It can also control the conveying means.
• the control means may comprise a means of calculation, such as software which can determine a storage order and spatial positions for the articles i to be stacked on the pallet 5.
• control means can also comprise a memory configured to host a database containing the characteristics of the packages to be stacked, for example, following an order from a customer.
• the database may include dimensions, weights or other characteristics of the items.
• Figure 2 shows an example of an arrangement of items on a pallet 5 being loaded using the method according to the invention.
• the method has made it possible to place two complete layers Ce superimposed, each comprising a set of articles having a similar height. Then, the articles i-1 to i-4 having close heights are arranged in a partial layers Ci occupying half the surface of the pallet 5. The articles i-5 to i-8 which have close heights are arranged in an additional partial layer Ci' occupying the other half of the surface of the pallet.
• Additional partial layers can be added on layers Ci and Ci′, for example one or more layers of the same dimensions can be superposed on Ci′. These two layers can also be separated by a spacer plate to reinforce the stability of the pallet. Spacers can also be added between full layers and between the upper complete layer Ce and the partial layers Ci, Ci' to increase the stability.
• the layer is added to the catalog.
• - z(C) is a value corresponding to the greatest profit of layers that it is possible to have by using a real number of layers of the catalog C.
• - 1 is a reference set of items i known to the system.
• - ni number of times the reference i can be used.
• Vc is the volume of the layer and has a real small enough that the profit of two layers is first evaluated according to the volume of the placed objects. For this same volume, the profit is compared on the volume that the layer occupies.
• the method is implemented by the software to choose from the catalog complete or partial layers to be placed on the container (pallet) by the robot 4.
• the layers of the catalog C chosen are those which maximize the sum of the profits ( p c ) subject to the constraint that all of the chosen layers can be arranged on the container and without exceeding a limiting height of the container, fixed upstream.
• the layers are selected by solving the following linear program (the resolution methods being known to operational research specialists):
• the constraint h(A) ensures that it is possible to place the set of layers without any exceeding the fixed limit height, noted H.
• the stress h(A) can be expressed as follows: where h c is the height of layer c.

Landscapes

• Stacking Of Articles And Auxiliary Devices (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=82693852

Family Applications (1)

Country Status (5)

Family Cites Families (4)

• 2022
  • 2022-02-24 FR FR2201644A patent/FR3132906B1/fr active Active
• 2023
  • 2023-02-23 US US18/840,176 patent/US20250162825A1/en active Pending
  • 2023-02-23 JP JP2024550560A patent/JP2025506834A/ja active Pending
  • 2023-02-23 EP EP23707701.1A patent/EP4482770A1/de active Pending
  • 2023-02-23 WO PCT/EP2023/054605 patent/WO2023161372A1/fr not_active Ceased

Also Published As

Similar Documents

Legal Events