CN113335809A

CN113335809A - Cargo sorting method, control terminal and automatic cargo sorting system

Info

Publication number: CN113335809A
Application number: CN202110529390.1A
Authority: CN
Inventors: 朱开磊; 周红霞
Original assignee: Shenzhen Hairou Innovation Technology Co Ltd; Shenzhen Kubo Software Co Ltd
Current assignee: Hai Robotics Co Ltd; Shenzhen Kubo Software Co Ltd
Priority date: 2021-05-14
Filing date: 2021-05-14
Publication date: 2021-09-03

Abstract

The embodiment of the invention relates to the technical field of warehousing management, in particular to a goods sorting method, a control terminal and an automatic goods sorting system. The method comprises the following steps: inputting a plurality of order boxes, wherein each order box corresponds to at least one order and each order records at least one kind of goods; taking the goods recorded by the order form out of the received container and putting the goods into a corresponding order form box; when all goods recorded in the order are put into the corresponding order box; and outputting the order box. Through the mode of presetting the order case, the step of order operation has obtained effectual simplification, fine promotion order operation's efficiency to make goods automatic sorting system have higher operating efficiency.

Description

Cargo sorting method, control terminal and automatic cargo sorting system

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of warehousing management, in particular to a goods sorting method, a control terminal and an automatic goods sorting system.

[ background of the invention ]

With the increasing enhancement and development of social business trade, the importance and concern of logistics and warehousing management is also increasing. How to provide fast and efficient logistics and warehouse management services is a current hot issue.

By means of the development of electronic information technology, for example, industrial robots and other automation industries, when warehouse management is performed on a plurality of existing goods warehouses, a mode that robots, conveying lines or other automation equipment are matched with one another is adopted, so that efficient goods or warehouse management is achieved. The picking operation of taking the goods out of the cargo box and performing corresponding packing operation to form the final order package has a plurality of complicated steps, and the conventional mode of low efficiency, such as manual operation, is also a main node for limiting the overall efficiency of the automatic warehouse management system.

Therefore, how to effectively carry out reasonable planning and simplification to the operation of choosing goods to promote the efficiency of choosing goods operation as far as possible, thereby promote whole system efficiency, with better satisfying the actual use needs be the problem that current automated warehouse management system urgently needs to solve.

[ summary of the invention ]

In order to solve the technical problem, embodiments of the present invention provide a cargo sorting method with high cargo picking efficiency, a control terminal and an automatic cargo sorting system thereof.

In order to solve the above technical problems, embodiments of the present invention provide the following technical solutions: a goods sorting method. The goods sorting method comprises the following steps:

inputting a plurality of order boxes, wherein each order box corresponds to at least one order and each order records at least one kind of goods;

taking the goods recorded by the order form out of the received container and putting the goods into a corresponding order form box;

and when all goods recorded in the order are put into the corresponding order box, outputting the order box.

Optionally, the "taking out the goods recorded in the order from the received container and placing the goods into the corresponding order box" specifically includes:

determining at least one order to be sorted;

enabling the order box corresponding to the order to be sorted to enter a sorting station;

receiving a container loaded with the target goods of the order record to be sorted;

in the sorting station, the target goods are taken out of the totes and placed into the order boxes.

Optionally, the "entering at least one order box into a sorting station" specifically includes:

determining a degree of duplication of the recorded categories of goods between different ones of the orders;

and simultaneously enabling at least two order boxes to enter the sorting station so as to enable the at least two orders to be sorted to have the highest repetition degree.

Optionally, the "receiving a container loaded with the target goods of the order record to be sorted" specifically includes:

preferably receiving a container loaded with a repeat good, the repeat good being a good recorded simultaneously by at least two of the orders to be sorted.

Optionally, the degree of repetition comprises: the quantity of the same kind of goods recorded between different orders and the ratio of the quantity of the same kind of goods recorded between different orders to the total quantity of goods.

determining a plurality of target containers required for completing the order to be sorted, wherein all goods loaded by the plurality of target containers are consistent with all target goods recorded by the order to be sorted;

inputting the plurality of target containers;

receiving the plurality of target containers sequentially at the sortation station.

Optionally, after the "taking out and putting the target cargo into the order box", the method further comprises:

outputting the currently received target container from the sorting station.

Optionally, the method further comprises:

when the incoming target container cannot be received by the sorting station, it is transferred to a container buffer for temporary storage and

when the input order box can not enter the sorting station, transferring to an order box buffer area for temporary storage; wherein the container buffer and order box buffer are both connected to the sorting station.

Optionally, after all the goods recorded in the order are placed in the corresponding order box, the method further includes:

packing the order box to form an order package;

and outputting the order package.

Optionally, the order box corresponds to two or more orders; after outputting the order box, the method further comprises:

and carrying out secondary sorting on the output order box according to the order corresponding to the order box to form a plurality of order packages.

In order to solve the above technical problems, embodiments of the present invention further provide the following technical solutions: a control terminal. The control terminal includes: a processor, a communication interface, a memory, and a communication bus.

The processor, the communication interface and the memory complete mutual communication through a communication bus; the memory stores computer operating instructions to cause the computer operating instructions, when invoked by the processor, to perform the cargo sorting method as described above.

In order to solve the above technical problems, embodiments of the present invention further provide the following technical solutions: an automatic cargo sorting system. This goods automatic sorting system includes:

the order box conveying line is provided with an order box inlet for inputting the order box and an order box outlet for outputting the order package;

a container conveyor line provided with a container inlet for a container to enter and a container outlet for a container to exit;

a plurality of sortation stations connected to the order box conveyor line and the container conveyor line;

a control terminal for controlling the order box conveyor line and the container conveyor line, at which sorting station the goods sorting method as described above is performed.

Optionally, at least a portion of the order box conveyor line and the container conveyor line are endless conveyor lines for forming an order box buffer area and a container buffer area, respectively.

Optionally, the order box conveyor line and the container conveyor line are arranged in a stack, and a projection of the order box conveyor line in the vertical direction overlaps at least a part of a projection of the container conveyor line in the vertical direction.

According to the goods sorting method, the control terminal and the automatic goods sorting system, the order boxes corresponding to the orders are arranged, and only goods placing and packaging operations need to be executed, so that the steps of goods sorting operation are effectively simplified, and automatic goods sorting operation is easier to realize. From this, fine promotion pick the efficiency of goods operation to make goods automatic sorting system have higher operating efficiency.

[ description of the drawings ]

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Fig. 1 is a schematic view of an application scenario of an automatic cargo sorting system according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an order box conveying line according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a robot according to an embodiment of the present invention;

fig. 4 is a flowchart of a method of sorting goods according to an embodiment of the present invention;

FIG. 5 is a flowchart of a method for forming an order package according to an embodiment of the present invention;

FIG. 6 is a flow chart of a method of entering order boxes and containers into a sorting station optimization method according to an embodiment of the present invention;

fig. 7 is a flowchart of a method for sorting goods according to another embodiment of the present invention;

fig. 8 is a functional block diagram of a cargo sorting apparatus according to an embodiment of the present invention;

fig. 9 is a functional block diagram of a cargo sorting apparatus according to another embodiment of the present invention;

fig. 10 is a schematic structural diagram of a control terminal according to an embodiment of the present invention.

[ detailed description ] embodiments

In order to facilitate an understanding of the invention, the invention is described in more detail below with reference to the accompanying drawings and specific examples. It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. As used in this specification, the terms "upper," "lower," "inner," "outer," "bottom," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the invention and simplicity in description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

The goods sorting refers to a process of taking out goods corresponding to an order from a warehouse or other similar goods storage area for storing one or more kinds of goods, and forming a corresponding order package for delivery to the warehouse. The automatic goods sorting system is an integrated system which depends on automatic equipment such as robots and conveying lines and realizes a goods sorting process comprising a series of operations such as goods transportation, package packaging and the like.

The 'picking operation' is one of the operation links of the goods sorting process. Which may generally include one or more of retrieving goods corresponding to the contents of the order from a device or apparatus (e.g., a container) for storing the goods, placing the goods in a container such as a particular box, and sealing and packaging the goods to form a package corresponding to the particular order. In the present application, only a part of operations related to the goods sorting process is named as "picking operation" for the sake of simplicity of description, and does not constitute any limitation or hint to the "picking operation", and a person skilled in the art can adjust the content included in the picking operation according to the needs of the actual situation.

Fig. 1 is an application scenario of an automatic cargo sorting system according to an embodiment of the present invention. As shown in fig. 1, the application scenario can be roughly divided into a goods storage area 10 and a picking work area 30. Between these two areas, the transfer of goods between the goods storage area 10 and the picking work area 30 can be achieved by means of the conveyor line structure 20, several robots 40 and a control terminal 50.

The cargo storage area 10 is an area for storing cargo therein. In the goods storage area, the goods may in particular be stored or stored in any suitable form. For convenience of description, the square container and shelf storage mode is described as an example in the application scenario, but those skilled in the art can apply the square container and shelf storage mode to other storage modes of goods, not limited to the square container and shelf storage mode.

Typically, a plurality of identical or different containers are placed on each pallet 11 according to a particular storage rule. Each container may contain one or more types of goods, and each type of goods may contain multiple pieces. In addition, the cargo box can mark the cargo stored in the cargo box by a feature (such as a two-dimensional code or a bar code and the like, a special color of the cargo box) arranged outside the cargo box.

With continued reference to fig. 1, a plurality of pallets 11 in the cargo storage area 10 are partitioned at intervals to form a plurality of lanes or similar travel paths having a width such that a robot or the like can move to a specific position to take a container from the pallet or return the container to the pallet.

In some embodiments, in a storage mode in which each container is filled with a plurality of goods, the transfer of the goods generally comprises two first conveying paths a and two second conveying paths B which are opposite in conveying direction.

Specifically, the first conveyance path a is: the containers taken out of the goods storage area 10 are transported to the picking work area 30 through the conveyor line structure 20, and the goods transportation path for picking operation is completed in the picking work area 30 (i.e., from the goods storage area 10 to the conveyor line structure 20 to the picking work area 30). And the second input path B means: after a specific quantity and type of goods are retrieved from the pick work area 30, the containers are again transported by the conveyor line structure 20 back to the goods transport path of the goods storage area 10 for storage (i.e., from the pick work area 30 to the conveyor line structure 20 to the goods storage area 10).

The pick work area 30 is named according to the "pick operation" process it is to perform, and is another external area different from the goods storage area 10. Which may generally consist of one or more identical or different sorting stations 31 (e.g. 2 as shown in fig. 1).

The "sorting station 31" is a work area where the order picking operation of one or more orders can be performed independently. The specific manner of executing or implementing the picking operation can be set by a technician according to the needs of actual conditions, such as an automatic manner, a semi-automatic manner or even a full-worker operation manner.

In some embodiments, the sorting station 31 may be a station that performs picking with order boxes. By "order box" is meant a carton of suitable dimensions or similar container for holding goods contained in the contents of an order. Each order box has a corresponding relationship with the order, typically pre-set or provided according to the contents of the order, and is sized to receive a box or similar packaging (e.g., a bag) containing all of the goods contained in the contents of the corresponding order.

Specifically, the preset order box may be an empty box in which goods are not placed. In other embodiments, the pre-set order box may be a box that has one or more items placed therein, but is not yet full.

Through this order case that provides in advance, the operation of getting of realization goods that can be convenient to when the goods that the order case need be put into had been prepared, can be very fast with its packing encapsulation, form corresponding order parcel, thereby simple and fast's completion is picked the goods operation.

The conveyor line structure 20 is a device for establishing a transport path between a plurality of nodes, and realizing input and output of various materials between the nodes. It can be realized in particular by any type of conveyor line, having dimensions adapted to the material to be conveyed, for example a roller conveyor line having a specific width, or a belt conveyor line.

In some embodiments, the conveyor line structure 20 may include, divided by the material being conveyed: a container transfer line 21 and an order box transfer line 22.

Wherein the container conveyor line 21 is a conveyor line for transporting containers between the sorting station 31 and the goods storage area 10, provided with a container entrance for entering containers and a container exit for exiting containers, to realize the first and second conveying paths a and B described in the above embodiments.

The order box conveying line 22 is a conveying device for inputting order boxes to the picking station 31 and outputting the order boxes after the picking operation is completed at the picking station 31 to the subsequent processes. It can adopt the similar transfer chain structure with packing box transfer chain 21, also can select to adopt the structure different with the packing box transfer chain according to actual conditions's needs (if order case size, box material type etc.), only need can satisfy actual transmission needs can.

During the actual operation of the conveyor line structure 20, on the one hand, order boxes are fed into the picking station 31 via the order box conveyor line 22 for picking operation for sorting and packaging goods. On the other hand, the control terminal 50 controls the robot to transfer the container loaded with the goods required to be placed in the order box from the rack to the container transfer line 21. The container conveyor line 21 transports the containers to the picking station 31.

Finally, the containers are received at the picking station 31 and the desired goods are removed therefrom and placed in a predetermined order box and/or packaged (e.g., with adhesive tape) and then delivered via the order box delivery line 22. In addition, the removed containers are also output from the sorting station and returned to the cargo storage area 10 by container conveyor lines.

Specifically, with continued reference to fig. 1, the container conveyor line 21 may be comprised of a connecting conveyor line 211 and a common conveyor line 212.

Wherein the connecting transfer line 211 is a cargo box input/output channel extending to the cargo storage area 10. It may be provided in a plurality of strips, possibly with different transport directions, for use as the container inlet and container outlet as described above. In this embodiment, to distinguish the conveying lines having different conveying directions, the "first connecting conveying line" is used to indicate the connecting conveying line for realizing the first conveying path, and the "second connecting conveying line" is used to indicate the connecting conveying line for realizing the second conveying path.

It should be noted that the above-mentioned "first connecting conveyance line" and "second connecting conveyance line" are used only for distinguishing the conveyance direction, and do not limit the concrete implementation of the connecting conveyance lines or imply the interrelation between the connecting conveyance lines. For example, a specific first connecting transport line 211a may be changed to a second connecting transport line 211b by changing the transport direction according to the actual situation.

The common transport line 212 is a transport trunk line connected to the sorting station 31 and each of the connecting transport lines 211, respectively. A certain number of nodes are provided on the common transport line 212, of which a part (also called picking node) extends to the sorting station 31 and another part is connected to the connecting transport line 211 (i.e. the position where the connecting transport line 211 is connected to the common transport line 212).

In one aspect, containers may exit the common conveyor line 212 from a particular picking node into the sorting station 31 and return to the common conveyor line 212 via the picking node after the picking operation is complete.

On the other hand, the containers can also enter the common transport line 212 from the first connecting transport line 211a and, after leaving the common transport line 212, be returned to the goods storage area 10 via the second connecting line 211 b.

In a preferred embodiment, at least a portion of the order box conveyor lines 22 may be in the form of a loop that serves as a buffer for temporarily storing order boxes to accommodate the need for a balanced order box and container arrangement. Fig. 2 is a schematic structural diagram of the order box conveying line 22 according to the embodiment of the present invention. As shown in fig. 2, the order box delivery line 22 may include: a first transfer line 221, a second transfer line 222, and an endless transfer line 223.

The first conveying line 221 is an infeed channel for feeding or receiving order boxes, so that the order boxes that have been set in advance can be conveyed into the sorting station 31. Of course, a two-dimensional code scanning device or similar order scanning device S may be added to the first conveying line 221 to help determine the specific order corresponding to the order box and the specific goods to be loaded in the order.

Specifically, the order data information obtained by scanning by the scanning device S can be provided to the control terminal 50, so as to help the control terminal 50 coordinate and optimize the condition of the input containers, thereby achieving the effect of further improving the picking operation efficiency. For example, the control terminal 50 may determine the target goods to be loaded into the order box according to the order scanned by the scanning device 23. The control terminal 50 may then adjust the container conveyor lines and robots accordingly to allow containers loaded with the target items to arrive at the sorting station 31 in synchronism with the order boxes for rapid picking operations.

The second transfer line 222 is an output passage that transfers in the opposite direction to the first transfer line 221. Which is used to receive the order boxes output from the sorting station 31 and output or transfer them to subsequent operations (e.g., loading, shipping, etc.).

The endless conveyor line 223 connects the first conveyor line 221 and the sorting station 31 and is a buffer area before the order boxes enter the sorting station 31. Which has an endless configuration, the first conveyor line 221 and the sorting station 31 are each coupled into the endless conveyor line 223 at a different location of the endless conveyor line 223.

In actual use, the order boxes entering the endless conveyor line 223 through the first conveyor line 221 can normally move a distance on the endless conveyor line 223, and after reaching the access position of the sorting station 31, leave the endless conveyor line 223 and enter the sorting station 31. When the sorting station 31 is busy and cannot accommodate the entry of a new order box, the order box can be moved in a loop conveyor 223 until it reaches the access position of the sorting station 31 next time. Thus, the effect of temporarily storing the order box is achieved.

In particular, the common conveyor line 212 of the container conveyor line 21 may also be of a similar endless configuration to the endless conveyor line 223, to achieve a similar effect of temporarily storing containers.

The container buffer area and the order box buffer area formed by the annular conveying lines can temporarily store a certain number of containers and order boxes. Thus, in the event of a delay or an obstacle to the picking operation performed by the sorting station 31, without affecting the operation of the goods storage area 10 on the other side of the conveyor line structure 20, the first connecting conveyor line 211a or the first conveyor line 221 can still continue to receive containers and order boxes, which are superfluous and can be taken up by the container buffer and the order box buffer described above.

Of course, in the case of using the common conveying line as the annular conveying line, the common conveying line may further serve to release the binding relationship between the connecting conveying line and each sorting station (that is, each container transported by the first connecting conveying line 211a may be selected to perform the cargo sorting operation at any sorting station according to the idle condition of the sorting station, and a container after the cargo sorting operation is completed at each sorting station may also be selected to return to the cargo storage area 10 at any second connecting conveying line 211b through the common conveying line according to the idle condition of each second connecting conveying line 211 b), which is favorable for achieving the balance between the connecting conveying line and the sorting station.

In a preferred embodiment, as shown in fig. 1, the order box conveyor line 22 and the container conveyor line 21 may also be stacked to have a larger proportion of overlap in the vertical direction (the dotted line of the order box conveyor line 21 indicates that it is vertically shielded by the container conveyor line 21 above), so as to maximize the utilization of the site space and reduce the site area occupied by the conveyor line structure 20.

For example, the common line 212 of the container line 21 and the endless line 223 of the order box line 22 may form one endless line of a double structure. The upper endless conveyor line is used as the common conveyor line 212, and the lower endless conveyor line is an endless conveyor line 223 corresponding to the order box conveyor line 22.

Correspondingly, the sorting station 31 may also have an arrangement adapted to the double-deck structure described above, as well as a container pick-up station adapted to the taller container conveyor line 21 and a goods deposit station adapted to the shorter order box conveyor line 22, for transferring goods picked up from containers into order boxes.

The robot 40 refers to an automated cargo handling device (e.g., an AGV cart, etc.) deployed in the cargo storage area 10. Which has one or more functional components, such as a traveling mechanism and a cargo storage mechanism, and can place a cargo container on the first connecting conveyor line 211a or take the cargo container away from the second connecting conveyor line 211b under the control of the control terminal 50.

Typically, the robot 40 needs to enter or park in a particular area near or near the connecting conveyor line 211 to be able to complete the placement or retrieval of containers. In the present application, the term "work station" is used to indicate an area close to the goods conveying line where the robot can perform the operation of placing the containers. In other words, after the robot 40 moves into the placing station, the operation of transferring the container on the goods conveying line can be performed by the goods pick and place mechanism.

In some embodiments, as shown in fig. 3, the robot 40 includes: a moving chassis 41, a rack main body 42, a cargo storage bin 43, a carrying device 44, and a driving device 45.

The moving chassis 41 is a main body moving mechanism of the robot 40. Rollers or similar running mechanisms are provided at the base of the mobile chassis 41.

The support body 42 is a robot body structure formed by extending upward based on the moving chassis 41. The bracket body 42 may be provided with corresponding mounting structures to provide a fixed position for one or more structural members.

The cargo storage container 43 is provided on the stand body 42, has a size adapted to a cargo box, and can be used as a storage space for separately storing the cargo box. Which may be embodied as a shelf, tray or other drawer-like structure carrying a container.

The plurality of cargo storage bins 43 provided in the robot may be arranged in any type of arrangement or arrangement, for example, as shown in fig. 3, a vertical arrangement may be adopted, and the plurality of cargo storage bins 43 may be stacked in the height direction, as required by one or more other practical situations, such as the main structure design of the robot 40.

The handling device 44 is a structural assembly for handling and transferring containers. The container can be a clamp type carrying device, a push-pull type carrying device or a mechanical arm and the like, and can be taken out from a cargo storage bin or put into the cargo storage bin.

The driving device 45 is a member for driving and guiding the above-described carrying device 44 to move between the respective cargo storages 43. Which may determine the particular drive type used depending on the arrangement of the plurality of cargo storage bins 43 in the robot 40 and the particular handling device 44 used.

For example, as shown in fig. 3, in the case where a plurality of cargo storage bins 43 are stacked in the height direction, the driving device 45 may be a lifting unit provided on the rack main body 42. It is possible to lift the carrying device 44 in the height direction or to lower the carrying device 44 so that the carrying device 44 is moved to any one of the cargo storage bins 43.

In other embodiments, the robot 40 may also be a robot driven by electricity, and includes functional components such as a battery and an electric driving mechanism. In order to meet the requirement that the robot driven by electric power keeps running continuously for a long time, a charging area for charging the robot 40 can be additionally arranged in the application scene. The robot 40 performs a work task from the charging zone after the charging is completed, and may return to the charging zone for charging in the case of a shortage of power.

The control terminal 50 is a control core of the entire article sorting system. It may be embodied in any type of electronic computing platform or server device having storage space and computing power to meet the needs of the actual situation to provide one or more application services or functions. The present invention is not limited to the specific implementation of the control terminal 50.

The robot 40 and the conveyor line structure 20 are both in communication with the control terminal 50. The control terminal 50 performs operations such as path planning of the robot according to information such as the position and the function index of the robot 40, controls the robot to complete carrying work of the containers, and transfers appropriate order boxes and containers to a sorting station to perform sorting operation.

Of course, those skilled in the art may adjust, replace or change one or more devices in the above application scenarios according to the needs of the actual situation, and are not limited to the one shown in fig. 1. For example, different sized containers may be placed in the cargo storage area 10 and robots adapted to the different sized containers may be deployed accordingly.

In the conventional picking operation, all the goods recorded in the order are taken out from the containers respectively arriving at the sorting station 31 according to the contents of the order and are packed to form a final order package. It will be appreciated that such picking operations require relatively cumbersome steps to accommodate different orders and containers received by the sorting station 31. When a plurality of continuous orders and containers are input, errors and queue waiting phenomena are easily caused.

Fig. 4 is a flowchart of a method for sorting goods according to an embodiment of the present invention. The goods sorting method can be realized based on the conveying line structure 20 and the control terminal 50 shown in fig. 1, so that the steps of goods sorting operation are simplified well, and the problem of queuing can be effectively solved. As shown in fig. 4, the robot control method includes:

s100, inputting a plurality of order boxes. Wherein, each order case corresponds to at least one order, and each order record has at least one goods.

In the present embodiment, the "order box" is a container prepared in advance for housing one or more pieces of goods. The size, material or shape of the box can be determined according to the needs of actual conditions (such as packaging habits, cargo properties of stored goods and the like), and for example, a square carton with a specific size can be adopted.

An "order" is a complete instruction provided to the automated cargo sorting system for execution. Which typically contains or records a variety of data information, such as a particular cargo or cargoes. Of course, the order may also contain or record other data information besides goods, based on different usage scenarios, such as: a consignee address, a consignee or delivery time limit, etc.

The order box and the order box have a corresponding relation, and data information such as goods required to be loaded into the order box, destinations required to be sent after order packages are formed and the like is recorded. Each order box may correspond to one order or several different orders.

The order may be bound to the order boxes in any suitable manner, so that the control terminal 50 can obtain the order corresponding to each order box and determine the goods to be placed in the order box. For example, the corresponding relationship between the order box and the order can be bound by arranging a unique order identifier (such as a two-dimensional code) on the outer surface of the order box. The control terminal 50 may scan and read the codes on the order boxes to determine the order corresponding to the order box by a code scanning device or the like provided on the conveyor line structure 20.

S200, taking the goods recorded in the order form out of the received packing box and placing the goods into the corresponding order box.

Wherein "receiving" refers to the condition where a container has been diverted through the conveyor line structure 20 to the sorting station 31 from which the order-recorded goods can be retrieved. Specifically, the container may adopt the cargo storage manner shown in fig. 1, and a plurality of same kinds of cargo may be stored in one container at the same time.

The goods removed from the container are then further transferred to an order box for placement under the direction or control of the control terminal 50 to complete the complete picking operation.

The above-mentioned operation of taking out the goods and putting into the order box can be realized by manpower, and also can be realized by a similar automatic mode such as manipulator grabbing. In the case of manual implementation, the control terminal 50 may help prompt the operator to place a particular item into an appropriate order box by text, voice, etc. In the case of implementation of an automation device, the control terminal 50 may directly complete the operation by issuing a control instruction.

And S300, outputting the order box after all the goods recorded in the order are put into the corresponding order box.

In some embodiments, where an order box corresponds to an order, each order box forms an order package directly. In the case of an order box corresponding to two or more orders, the order box may also be temporarily not fully enclosed in the picking station, but may continue to be sorted in subsequent stations to form different small order packages on the basis of large order packages.

An "order package" is a package of goods that is packaged in a package of adhesive tape or the like after all the required goods of the order record have been placed in an order box or other similar container, and that can be used for further subsequent transfer.

Based on different specific implementation structures or application scenarios, step S300 may be implemented by using corresponding specific steps. Fig. 5 is a flowchart of a method for completely implementing step S300 based on the conveyor line structure 20 shown in fig. 1. As shown in fig. 5, the step S300 may include:

s310, determining at least one order to be sorted.

The "order to be sorted" refers to an order that the control terminal 50 needs to process currently or perform a goods sorting operation. The control terminal 50 may select the order to be sorted by any suitable means, for example, the scanning device S shown in fig. 2 may scan the passing order boxes, and use the obtained order information of the order boxes as the order to be sorted.

In addition, the orders to be sorted that can be processed simultaneously by the control terminal 50 have an upper limit value, which may be set specifically based on one or more practical situations of the processing capacity of the control terminal 50, the number of sorting stations, and the like.

And S320, enabling the order box corresponding to the order to be sorted to enter a sorting station.

The control terminal 50 can control the order box conveying line 21 to selectively control one or more specific order boxes to enter the sorting station 31, so as to perform the picking operation for the order to be sorted.

The order boxes may be controlled in order in any suitable manner, for example, by arranging a scanning device to scan and read a barcode located on one side of each order box, so as to determine the order corresponding to the order box, and further determine whether to output the order from the endless conveyor line 22 and enter the corresponding sorting station.

S330, receiving a container loaded with target goods to be sorted and recorded by an order.

The term "target goods" refers to goods that have not been sorted or placed in an order box, and are recorded by an order to be sorted. It should be noted that it is not a specific cargo, but may vary according to the actual situation.

In this embodiment, the control terminal 50 may control the container conveying line 21 in a similar manner to step S320, so as to sequentially select the containers received by the sorting station 31, and enable the target goods to be picked out and placed into the order boxes in time.

Specifically, based on the cargo conveyor line 21 shown in fig. 1, step S330 may include the following steps, so that all the containers required to be used can be received by the sorting station.

And S331, determining a plurality of target containers required for completing the order to be sorted.

Wherein "target containers" refer to those containers loaded with target cargo. The control terminal 50 may determine a number of target containers specifically required according to all the target goods recorded by the order to be sorted.

"all target items" is the sum of the items recorded for all orders to be sorted currently being processed. It is understood that the set of all target cargo components should be a subset of the set of cargo components loaded by the target cargo containers determined in step S331.

And S332, inputting a plurality of target containers.

In this embodiment, the "input" refers to a process that the control terminal 50 can control the robot 40 to transfer all target containers to be used from the cargo storage area 10 to the container entrance of the cargo conveying line 21 after determining all the target containers. In other words, "input" means that the target container enters the cargo conveyor line 21.

And S333, sequentially receiving a plurality of target containers at the sorting station.

The number of containers that can be simultaneously accommodated by each sorting station is a preset upper limit value. The specific upper number may be determined or set by the skilled person as required by the actual situation, e.g. two or other different numbers.

Typically, the number of target containers determined in step 331 is significantly higher than the upper limit. Therefore, a plurality of target containers entering the goods conveying line 21 need to be sequentially received by the sorting station according to a certain arrangement order to complete the goods sorting operation.

Of course, after the target goods in the target container are removed, the target container is withdrawn from the sorting station, transported by the conveyor line structure 20 and the robot 40, and returned to the goods storage area 10 for storage.

And S340, taking out the target goods from the goods box and placing the target goods into the order box in the sorting station.

In this embodiment, the removal of goods from the container and placement of the goods into the order box may be accomplished manually, by automated equipment (e.g., a robotic arm), or by a combination thereof. Automated equipment may have higher efficiency and lower error rates, but are more costly to implement. Manual operation has features that are easy to implement, but there may be a high error rate.

In the process of performing the goods sorting operation at the actual sorting station, the above steps S330 and S340 need to be repeatedly performed until all the goods recorded in the order to be sorted have been placed in the corresponding order box.

With continued reference to fig. 5, after step S340, the following steps may be further included to ensure that the goods recorded in each order to be sorted are placed:

and S350, determining whether the target goods recorded in the order to be sorted are all put into the corresponding order box. If yes, go to step S360. If not, the currently received target container can be output from the sorting station, and after a space for accommodating the container is reserved, the process returns to step S330, and another target container is received.

And S360, packaging and packaging all goods in the order box to form an order package.

In particular, the order box may be packaged in any suitable manner, such as by adhesive tape or the like, to form a sealed or enclosed package.

In some embodiments, the order boxes may also be temporarily not fully enclosed in the picking station, but continue to be sorted in subsequent stations to form different small order packages on the basis of order boxes that have completed the picking operation.

For example, one order box may correspond to two orders having the same ship-to address, but different ship-to recipients. In this way, after the order boxes containing all the goods contained in the two orders are output from the order box conveyor line, the two small order packages for different consignees are further sorted into form.

After sorting, packaging to form order packages or completing picking operations, the order packages or order boxes may be output from the sorting station 31 and transported to other process stations via the conveyor line structure 20 for subsequent further processing (e.g., shipment, dispatch, etc.). The empty positions formed after the output of the sorting station 31 can be re-entered into new order boxes.

According to the goods sorting method provided by the embodiment of the invention, the preset order boxes which correspond to the orders one by one are provided, so that the operation of goods sorting work can be effectively simplified, the efficiency of sorting stations is improved, the automatic sorting stations are easier to realize, and the overall efficiency of the system is effectively improved.

In some embodiments, the efficiency of the goods sorting operation may be further enhanced by optimizing the manner in which the order boxes enter the sorting station (i.e., step 320). As shown in fig. 6, step S320 may specifically include the following steps:

s321, determining the repetition degree of the recorded goods types among different orders.

Here, "degree of repetition" refers to an index for measuring the degree of similarity of the kinds of goods recorded between orders. Any suitable standard can be selected and used according to the needs of the actual situation.

For example, in the case where the order records a small number of goods or the number is not very different, the degree of repetition may be the number of the same kind of goods recorded between different orders. Thus, the more items of the same type are recorded between orders, indicating a higher degree of duplication between orders.

The degree of repetition may be a ratio of the number of the same kind of goods recorded between different orders to the total number of goods when the difference between the number of goods recorded between different orders is large or the number of goods recorded for a part of orders deviates significantly from the average value.

Wherein, the total goods quantity refers to the sum of the goods quantities recorded by two or more orders for comparing the repetition degree. Thus, the real repetition degree of the order can be reflected exactly by the mode expressed by the ratio index.

And S322, enabling at least two order boxes to enter the sorting station at the same time so that the at least two orders to be sorted have the highest repetition degree.

In this embodiment, the order box with higher overlapping degree of the corresponding order has higher priority. In other words, order cases with higher overlap may be preferentially selected for simultaneous entry into the sorting station for performing the goods sorting operation.

By the above-described manner of determining the order boxes that preferentially enter the sorting station based on the degree of repetition, it can be ensured that there are always more items that are repeated between order boxes that are simultaneously performing the item sorting operation in the sorting station. Since the same cargo is loaded in one cargo box. Therefore, the optimization mode can be combined to carry out repeated goods taking and putting operations, so that the number of containers required to be received for completing the goods sorting operation of one order box each time is reduced as much as possible, and the efficiency of the system is improved.

Preferably, in addition to optimizing the manner in which order boxes enter the sorting station, the manner in which the sorting station receives the containers may be further optimized to expect greater system efficiency.

Referring to fig. 6, step S330 may specifically include: a container loaded with duplicated goods is preferentially received (S331). Wherein "duplicate goods" refers to goods that are simultaneously recorded by at least two orders to be sorted. That is, the goods are required to be placed in each of two or more order boxes entering the sorting station.

By "priority" is meant that such containers have a higher priority relative to containers that are not loaded with repeat cargo. In the case of different priorities, the control terminal 50 may cause the containers with higher priority to be received by the sorting station 31 earlier by controlling the conveyor line 20 and the robot 40. Of course, a more detailed prioritization mode can be further set, and the priorities of the containers loaded with the repeated goods are further subdivided, so that the containers can be controlled more accurately.

In addition, those skilled in the art can further combine one or more optimization manners of the container priority setting manner and the priority setting manner of the order box disclosed in the above different embodiments to obtain other more preferred embodiments.

In other embodiments, in the case where the space available at the sorting station is limited (i.e., there is an upper limit for the number of order cases and containers that can be simultaneously received), the efficiency of the system may be further improved by optimizing the circulation of containers and order cases. As shown in fig. 7, after inputting the plurality of containers and the plurality of order boxes to the conveyor line structure 20, the method may further include the steps of:

and S710, judging whether the sorting station can receive the target container. If not, step S720 is executed, and if yes, step S340 is executed to take out the target cargo loaded in the target cargo box in the sorting station.

And S720, transferring the target container to a container buffer area for temporary storage.

Wherein the container buffer is an area formed in the conveyor line structure 20 where one or more containers may be temporarily stored. Which is connected to the sorting station and to the goods conveyor line, can receive a number of containers and supply them to the sorting station when required.

And S730, judging whether the input order box can enter a sorting station or not. If not, go to step S740. If yes, step S320 is executed, and the order box enters a sorting station to perform a cargo sorting operation, so as to complete the processing of the corresponding order.

S740, transferring the order box to the order box buffer area for temporary storage.

Wherein the order box buffer is also formed in the conveyor line structure 20, similar to the above-described container buffer, for an area for temporarily storing a specified number of order boxes. Which is connected to the sorting station and is capable of receiving order cases and re-transferring them into the sorting station when required.

In particular, the container buffer and order box buffer described in the above embodiments may be implemented in any suitable manner. For example, as shown in fig. 1 and 2, the container buffer may be formed by an endless common conveyor line, and the order box buffer may be formed by an endless conveyor line.

The containers or order boxes can be transported cyclically on the two conveyor lines with endless loop structure, respectively, in order to temporarily store the containers and order boxes. When needed, the goods leave from the annular common conveying line or the sorting node of the annular conveying line and enter a sorting station to be sorted.

The goods sorting method provided by the embodiment of the invention, which is provided with the buffer areas for temporarily storing the order boxes and the goods boxes, can not only remove the mutual influence relationship between the goods picking stations 31 at the two ends of the conveying line structure 20 and the goods storage area 10 to a certain extent, but also reduce the mutual influence between the order boxes and the goods boxes, so that the whole system can reach a balanced and stable state more easily, and the overall efficiency is improved.

For example, when the rate at which the sorting station 31 performs a picking operation is temporarily affected to be less than the rate at which the robot 40 moves the containers to the conveyor line structure 20, the container buffer area may provide a buffer capacity such that the robot 40 does not have to wait for a pause. When the speed of the robot 40 for carrying the containers is not enough for the sorting station 31 to pick the containers, the containers temporarily stored in the container buffer area can be used as a supplement, so that the sorting station 31 does not need to pause waiting for the adjustment of the robot 40.

In addition, in the event that too many or unsuitable containers are provided, these containers may be temporarily stored in the container buffer area without waiting on the conveyor line, which would hinder the other containers from entering the sorting station.

Conversely, when too many order boxes are provided to be received by the sorting station 31, the excess order boxes may be temporarily stored in the order box buffer, and when the sorting station 31 is in the idle position, the excess order boxes may be moved away from the endless conveyor line and enter the sorting station 31.

It should be noted that, based on the characteristics of the cargo sorting method disclosed in the embodiment of the present invention (for example, the preset order box corresponding to the sorting order, the priority setting mode for the order box entering the sorting station and the container), those skilled in the art may also adjust, change or alternatively apply the task balancing method disclosed in the foregoing embodiment to other application scenarios with similar characteristics according to the actual application scenario.

Based on the cargo sorting method provided by the embodiment, the embodiment of the invention further provides a cargo sorting device. The goods sorting apparatus may be implemented by the control terminal 50 shown in fig. 1 to perform one or more steps of the goods sorting method described above. Fig. 8 is a cargo sorting apparatus according to an embodiment of the present invention. As shown in fig. 8, the goods sorting apparatus 800 includes: an order acquisition module 810, a goods pick-and-place module 820 and a package output module 830.

The order obtaining module 810 is configured to obtain orders corresponding to a plurality of input order boxes. Each order box corresponds to at least one order, and each order records at least one kind of goods. The goods taking and placing module 820 is used for taking the goods recorded by the order from the received packing boxes and placing the goods into the corresponding order boxes. The package output module 830 is configured to perform a packing operation after all the goods recorded in the order are placed in the corresponding order box, so as to form an order package and output the order package.

In the actual operation process, firstly, the order corresponding to the input order box is obtained through the order obtaining module 810, and then the goods to be sorted are determined. Then, the goods taking and placing module 820 sends out a control command to control an automated device such as a robot arm, etc., to take out the goods recorded in the order from the received container and place the goods into the corresponding order box. Finally, after all the goods recorded in the order are placed in the corresponding order boxes, the package output module 830 sends out corresponding operation instructions or prompt information, and performs packaging operation on the order boxes in which the goods are placed, so as to form order packages and output the order packages.

In some embodiments, such as where there are multiple orders for an order box, the package output module 830 may be omitted, and the order box after the picking operation is completed may be output for further sorting at a subsequent station.

In some embodiments, as shown in fig. 9, the cargo handling module 820 for performing the cargo handling function may include: an order processing unit 821, an order box control unit 822, a container receiving unit 823, and a goods processing unit 824.

The order processing unit 821 is configured to select and determine at least one order to be sorted among a plurality of orders. The order box control unit 822 is configured to control an order box conveying line to enable the order box corresponding to the order to be sorted to enter a sorting station according to the selected order to be sorted. The container receiving unit 823 is configured to control the container conveying line to receive a container loaded with the target goods to be sorted according to the order record. The goods handling unit 824 is configured to take the target goods out of the goods box and put the target goods into the order box at the sorting station.

Preferably, the cargo taking and placing module 820 can adopt an optimization strategy of preferentially performing cargo sorting operation on repeated cargos when selecting and receiving order boxes and cargo boxes, so that the number of cargo boxes required to be received by a sorting station in performing cargo sorting operation on one order box is minimum, thereby achieving the effect of improving the system efficiency.

Specifically, the goods pick-and-place module 820 may first determine the degree of repetition of the recorded goods categories between different orders. Then, at least two order boxes enter the sorting station at the same time so as to enable the highest repetition degree between at least two orders to be sorted. The cargo access module 820 may preferentially receive cargo containers loaded with duplicate cargo for the cargo container access sequence.

The repeated goods are the goods recorded by at least two orders to be sorted simultaneously. The repetition degree of the goods types can be the quantity of the same goods recorded among different orders, or the ratio of the quantity of the same goods recorded among different orders to the total quantity of the goods, or other measurement standards determined according to the needs of actual conditions.

In some embodiments, the container receiving unit 823 may be specifically configured to: first, a plurality of target containers required to complete the order to be sorted is determined. And then controlling the goods conveying line and the robot to enable the plurality of target containers to be input into the goods conveying line. Finally, the target containers are received at the sorting station in sequence according to their priority using one or more of the optimization strategies provided in the above embodiments.

In other embodiments, with continued reference to fig. 8, the goods sorting apparatus may further include a determining module 840 for determining whether the goods in the order box are ready.

In an actual operation process, after the goods taking and placing module 820 finishes taking and placing the goods once, the determining module 840 is configured to determine whether all the target goods recorded in the order to be sorted have been placed in the corresponding order box.

On one hand, after the determining module 840 determines that all the target goods recorded in the order to be sorted have been put into the corresponding order box, the package outputting module 830 controls the completion of the packing operation to form the order package and output the order package. On the other hand, when the determining module 840 determines that the target goods recorded in the order to be sorted are not all placed in the corresponding order box, the goods taking and placing module 820 continues to perform the next goods taking and placing operation.

In applications where a buffer is provided for temporarily storing a number of containers and order boxes, as shown in fig. 1, the load sorting apparatus may further include an equalization module 850.

The equalization module 850 is operable to transfer to a container buffer for temporary storage when the incoming target containers cannot be received by the sorting station and to an order box buffer for temporary storage when the incoming order boxes cannot enter the sorting station. The order boxes and containers temporarily stored in the sorting station can exit from the buffer area at any time under the condition that the sorting station is idle, and enter the sorting station again to perform sorting operation.

Through the balancing module 850, the balance between the order box and the container can be realized, the situation that the order box and the container are queued to wait in the process of picking and placing the goods is avoided, and the overall efficiency of the system can be effectively improved.

It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the apparatuses and modules described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention. The computer software may be stored in a computer readable storage medium, and when executed, may include the processes of the embodiments of the methods described above. The storage medium may be a magnetic disk, an optical disk, a read-only memory or a random access memory.

Fig. 10 shows a schematic structural diagram of the control terminal 50 according to the embodiment of the present invention. As shown in fig. 10, the control terminal 50 may include: a processor (processor)502, a Communications Interface 504, a memory 506, and a communication bus 508.

Wherein: the processor 502, communication interface 504, and memory 506 communicate with one another via a communication bus 508. A communication interface 504 for communicating with network elements of other devices, such as clients or other servers. The processor 502 is configured to execute the program 510, and may specifically execute the relevant steps in the above-described cargo sorting method embodiment.

In particular, program 510 may include program code that includes computer operating instructions.

In the embodiment of the present invention, the Processor 502 may be a Central Processing Unit (CPU), and the Processor 502 may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate arrays (FPGAs) or other Programmable logic devices, discrete Gate or transistor logic devices, discrete hardware components, etc. according to the type of hardware used.

The memory 506 is used to store a program 510. The memory 506 may comprise high-speed RAM memory, and may also include non-volatile memory (non-volatile memory), such as at least one disk memory. The program 510 may specifically be configured to cause the processor 502 to execute the goods sorting method in any of the above-described method embodiments.

The embodiment of the invention also provides a computer readable storage medium. The computer readable storage medium may be a non-volatile computer readable storage medium. The computer-readable storage medium stores a computer program.

Wherein, the computer program is executed by a processor to realize one or more steps of the data automatic association method disclosed by the embodiment of the invention. The complete computer program product is embodied on one or more computer readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing the computer program disclosed by the embodiments of the invention.

In summary, the goods sorting method provided by the embodiment of the invention has the advantages that the operation steps required for forming order packages are simplified well by providing the preset order boxes, the goods sorting efficiency is improved, and the overall operation efficiency of the system is further improved.

Based on the goods sorting method, the goods automatic sorting system further realizes the arrangement of the order box buffer area and the goods box buffer area through simple structural design, and can temporarily store a certain number of order boxes and goods boxes, so that the balance between the order boxes and the goods boxes is ensured in the process of sorting goods at sorting stations, and the phenomenon of queuing each other is avoided.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; within the idea of the invention, also technical features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of sorting goods, comprising:

2. The method for sorting goods according to claim 1, wherein the step of taking out the goods recorded in the order from the received container and placing the goods in the corresponding order box comprises:

determining at least one order to be sorted;

3. The method for sorting goods according to claim 2, wherein said "letting at least one of said order boxes enter a sorting station" comprises:

4. The method for sorting goods according to claim 3, wherein the "receiving a container loaded with the target goods of the order record to be sorted" comprises:

5. The method of sorting goods as in claim 3, wherein the degree of repetition comprises: the quantity of the same kind of goods recorded between different orders and the ratio of the quantity of the same kind of goods recorded between different orders to the total quantity of goods.

6. The method for sorting goods according to any one of claims 2 to 5, wherein the "receiving a container loaded with the target goods of the order record to be sorted" specifically comprises:

determining a plurality of target containers required for completing the order to be sorted;

inputting the plurality of target containers;

7. The cargo sorting method according to claim 6, wherein after the "taking out and putting in the order box the target cargo from the cargo box", the method further comprises:

outputting the currently received target container from the sorting station.

8. The method of sorting goods as in claim 6, further comprising:

9. The cargo sorting method according to any one of claims 1 to 5, wherein after all of the cargos recorded in the order are placed in the corresponding order box, the method further comprises:

packing the order box to form an order package;

and outputting the order package.

10. The cargo sorting method according to any one of claims 1 to 5, wherein the order box corresponds to two or more orders;

after outputting the order box, the method further comprises:

11. A control terminal, characterized in that the control terminal comprises: a processor, a communication interface, a memory, and a communication bus;

the processor, the communication interface and the memory complete mutual communication through a communication bus; the memory has stored therein computer operating instructions for causing the computer operating instructions, when invoked by the processor, to perform a method of sorting goods according to any of claims 1-10.

12. An automatic cargo sorting system, comprising:

the order box conveying line is provided with an order box inlet for inputting the order box and an order box outlet for outputting the order box which finishes the order picking operation;

a plurality of sortation stations connected to the order box conveyor line and the container conveyor line for performing a sort operation;

a control terminal for controlling the order box conveyor line and the container conveyor line, at which sorting station the goods sorting method according to any one of claims 1-10 is performed.

13. The automated cargo sorting system of claim 12, wherein at least a portion of the order box conveyor line and the container conveyor line are endless conveyor lines for forming an order box buffer area and a container buffer area, respectively.

14. The automated cargo sorting system of claim 12, wherein the order box conveyor line and the cargo box conveyor line are stacked, a projection of the order box conveyor line in a vertical direction overlapping at least a portion of a projection of the cargo box conveyor line in a vertical direction.