The present invention relates to a layout design of component shelves in warehouse in a production/distribution facility.
A typical example of an operation for delivering a desired component from warehouse is a picking operation. A form of the picking operation is a method in which an operator collects a specified component while moving around component shelves. For performing the picking operation efficiently in this method, it is important to optimize the arrangement of the component shelves in a picking area. Determination of the component-shelf arrangement described above is called component-shelf-layout design.
An example of a conventional method of the component-shelf-layout design that aims to improve the efficiency of the picking operation is a method described in Patent Literature 1 in which the arrangement of the component shelves is determined in accordance with a delivery frequency of each component. According to Patent Literature 1, an instruction to change a layout is issued in such a manner that a component having a high delivery frequency is arranged at a closer position to a reference position and a component having a low delivery frequency is arranged at a farther position from the reference position. Changing the component-shelf layout in accordance with the above-described method enables a picking operator to perform the picking operation in a shorter movement distance, so that the efficiency of the picking operation can be improved.
Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2011-215715
The conventional component-shelf-layout design method, such as Patent Literature 1, focuses only on the traveling movement distance in picking to improve the efficiency of the picking operation. Meanwhile, when component stock on a component shelf has decreased in an actual delivery facility, it is necessary to replenish components to the component shelf in the picking area from a backward storage shelf where components are stored. When the component stock on the component shelf has run out (stockout has occurred), the picking operation is interrupted. Therefore, for improving the efficiency of the picking operation, it is important to perform replenishment to prevent stockout.
In a component replenishment operation, a method is usually used in which when the component stock on the component shelf is below a threshold value (a replenishment point), the components are replenished until the stock amount reaches a preset number of components (a replenishment amount). An occurrence frequency of the replenishment operation is determined by the size of a component shelf to which each component is allocated. For example, as the component shelf for the component is larger, the replenishment amount can be set to be larger. Therefore, more components can be replenished in one replenishment operation, so that the occurrence frequency of the replenishment operation can be lowered. When the occurrence frequency of the replenishment operation is lowered, an occurrence of the stockout caused by delay of the replenishment operation can be suppressed. However, the larger component shelf increases an occupation area of the component shelf in the picking area and therefore the traveling movement distance in the picking is increased. As described above, it is necessary to consider both reduction of the traveling movement distance in the picking and suppression of the occurrence of the replenishment operation in the component-shelf-layout design.
In order to solve the above problem, the present invention is configured to include a storage unit and a control unit, for example. The storage unit stores picking-operation-results information including information on a delivery amount of each component, component-shelf-distance information including information on a distance between component shelves, and component-shelf-layout information indicating a component shelf, a component allocated to the component shelf, and the capacity of the component shelf. The control unit includes a picking-movement distance calculation unit calculating a picking-movement distance in each component-shelf layout using the information in the storage unit, a replenishment-occurrence frequency calculation unit calculating an occurrence frequency of a replenishment operation using the information in the storage unit, and a new component-shelf layout creation unit creating a plurality of new component-shelf layout proposals and adding them to the component-shelf-layout information. The picking-movement distance calculation unit and the replenishment-occurrence frequency calculation unit calculate the picking-movement distances and the occurrence frequencies of the replenishment operation for a current component-shelf layout and the component-shelf layout proposals created by the new component-shelf layout creation unit. An optimal component-shelf layout extraction unit is further provided that extracts a component-shelf layout proposal satisfying a predetermined condition from the component-shelf layout proposals created by the new component-shelf layout creation unit.
According to the present invention, a user of this device can determine a component-shelf layout that can improve the efficiency of a picking operation and suppress an occurrence of a replenishment operation simultaneously.
Details of an embodiment of the present invention are described below.
The storage unit 110 includes a picking-operation-results information storage area 111, a component/shelf allocation-availability information storage area 112, a component-shelf-distance information storage area 113, a component-shelf-layout information storage area 114, a component-shelf-layout change information storage area 115, a picking-operation information storage area 116, a replenishment-operation information storage area 117, and a parameter information storage area 118.
The picking-operation-results information storage area 111 stores information specifying a result of a past picking operation therein. In the present embodiment, for example, a picking-operation-results information table shown in
The component/shelf allocation-availability information storage area 112 stores therein information specifying availability of allocation of each component to each component shelf. In the present embodiment, for example, a component/shelf allocation-availability information table shown in
The component-shelf-distance information storage area 113 stores information specifying a distance between a component shelf and another component shelf. In the present embodiment, a component-shelf-distance information table shown in
The component-shelf-layout information storage area 114 stores information specifying a component-shelf layout. In the present invention, the component-shelf layout does not describe arranged locations or an arrangement form of the component shelves, but means specifying which component is allocated to each component shelf. For example, a component-shelf-layout information table shown in
The component-shelf-layout change information storage area 115 stores information specifying a change of component allocation when a layout is changed to another layout, which is a processing result of a component-shelf-layout change extraction unit described later. For example, a component-shelf-layout change information table shown in
The picking-operation information storage area 116 stores information specifying the movement distance of each round in the picking operation, which is a processing result of a picking-movement distance calculation unit described later. For example, a picking-operation information table shown in
The replenishment-operation information storage area 117 stores information specifying the number of occurrences of a replenishment operation of each component in each day, which is a processing result of a replenishment-occurrence frequency calculation unit described later. For example, a replenishment-operation information table shown in
The parameter information storage area 118 stores information specifying an item and a value of each parameter for which input is received in a display unit described later. For example, a parameter information table shown in
Returning to
The new component-shelf layout creation unit 121 performs a process that uses the component-shelf-layout information, the component/shelf allocation-availability information, and the component-shelf-distance information in the storage unit 110 to create a new component-shelf layout proposal. In the present embodiment, for example, the new component-shelf layout proposal is created by using current or new component-shelf-layout information and replacing component shelves of any of the two components. Information on the created component-shelf layout proposal is stored in new component-shelf-layout information.
The picking-movement distance calculation unit 122 performs a process that uses the picking-operation-results information, the component-shelf-distance information, and the component-shelf-layout information in the storage unit 110 to calculate a picking-movement distance in each component-shelf layout. The details of this process will be described later.
The replenishment-occurrence frequency calculation unit 123 performs a process that uses the picking-operation-results information and the component-shelf-layout information in the storage unit 110 to calculate an occurrence frequency of the replenishment operation in each component-shelf layout. The details of this processing will be described later.
The optimal component-shelf layout extraction unit 124 performs a process that uses the picking operation information and the replenishment operation information in the storage unit 110 to extract an optical component-shelf layout from the component-shelf layout proposals created by the new component-shelf layout creation unit. The details of this process will be described later.
The component-shelf layout change extraction unit 125 performs a process that uses the component-shelf layout extracted by the optimal component-shelf layout extraction unit 124 to extract a layout change when the current component-shelf layout is changed to an optimal component-shelf layout. The details of this process will be described later.
Returning to
The picking-operation-results management device 220 receives input from an information terminal used in a picking operation and manages information on the result of the picking operation. Also, the picking-operation-results management device 220 transmits picking-operation-results information to the component-shelf-layout design device 210 at a predetermined time or in response to a request from the component-shelf-layout design device 210. The component-shelf-layout design device 210 stores this information in the picking-operation-results information storage area 111.
The component-shelf-layout change instruction device 230 manages information on an allocation change instruction for each component to each component shelf. The component-shelf-layout change instruction device 230 receives the information in the component-shelf-layout change information storage area 115 from the component-shelf-layout design device 210 at a predetermined time or in response to a request from the component-shelf-layout design device 210.
In Step S100, results information of each round, used for evaluation of a component-shelf layout, is extracted from the picking-operation-results information table in
In Step S200, a current component-shelf layout L0 is acquired from the component-shelf-layout information table in
In Step S300, the picking-movement distance and the replenishment-occurrence frequency are calculated in the component-shelf layout L0. The process of calculating the picking-movement distance is a process by the picking-movement distance calculation unit 122 of the control unit 120. In calculation of the picking-movement distance, for each round extracted in Step S100, a group of component shelves to be traveled is extracted based on components to be picked in that round and the component-shelf layout L0 first. Then, the order of traveling the group of component shelves is determined, and the movement distance is calculated from the order of traveling and the component-shelf-distance information. Finally, a calculated value is stored in the picking-operation information table in
Calculation of the replenishment-occurrence frequency is a process by the replenishment-occurrence frequency calculation unit 123 of the control unit 120. In the calculation of the replenishment-occurrence frequency, transition of component stock on a component shelf with time is simulated using the delivery amount of each component at each date and time extracted in Step S100. During the simulation, it is assumed that when the component stock is below the replenishment point, the replenishment operation occurs, and the component stock is increased to the replenishment amount. By the above process, the number of occurrences of the replenishment operation is counted. The result of the process is stored in the replenishment-operation information table in
The processes in Step S400 and S500 are repeated from a value 1 of a counter n to a value N. Step S400 is a process by the new component-shelf layout creation unit 121 of the control unit 120 and creates a new component-shelf layout. More specifically, a component-shelf layout Ln is created by changing a portion of the component-shelf layouts L0 to Ln-1. The following two methods may be used as a changing method, for example. Either one of them may be used, or both may be applied alternately.
(1) For two components X and Y, component shelves to which they are allocated are replaced with each other, wherein a daily delivery amount is larger for the component X than for the component Y and the replenishment amount is larger for the component Y than for the component X.
(2) For two components X and Y, the component shelves to which they are allocated are replaced with each other, wherein the daily delivery amount is larger for the component X than for the component Y and a distance from the picking start point is smaller for the component Y than for the component X.
Note that the component/shelf allocation-availability information is referred to in the above process, and a restriction is provided to exclude a combination of a component and a component shelf for which allocation is not available. The number of created new component-shelf layouts is determined by predetermining the value for N or predetermining an upper limit of a calculation time. A condition other than the above can be added, for example, in which components simultaneously ordered are arranged at close positions to each other.
In Step S500, the picking-movement distance and the number of occurrences of replenishment are calculated for the component-shelf layout Ln created in Step S104. The details of this process are the same as those in Step S300, and therefore the description thereof is omitted.
In Step S600, an optimal component-shelf layout LOpt is extracted from the component-shelf layouts L0 to LN. Examples of an extraction method are a method that extracts a component-shelf layout minimizing the weighted sum of the picking-movement distance and the number of occurrences of replenishment, a method that extracts a component-shelf layout providing the picking-movement distance equal to or smaller than a threshold value and minimizing the number of occurrences of replenishment, and a method that extracts a component-shelf layout providing the number of occurrences of replenishment equal to or smaller than a threshold value and minimizing the picking-movement distance. A user can set each extracting condition and each threshold value.
In Step S700, a layout change is extracted when the current component-shelf layout L0 is changed to the optimal component-shelf layout LOpt. This process is a process by the component-shelf-layout change extraction unit 125 of the control unit 120. In this process, a group of components for which allocated component shelves are different between the layouts L0 and LOpt is extracted, and information on the component-shelf names before and after the layout change for that group of components is stored in the component-shelf-layout change information table.
In the present embodiment, evaluation values of the movement distance and the number of occurrences of replenishment in each component-shelf layout proposal are calculated using past picking operation results. However, instead of the past picking operation results, a delivery amount of each product in each future round is predicted and the above evaluation values can be calculated using the prediction result.
In the present embodiment, the picking-movement distance is described as the evaluation value. However, the picking-movement distance calculation unit 122 can convert the picking-movement distance to a picking-operation time by using information on a movement rate of an operator, information on an operation time when the operator picks up each product from each component shelf, and the like. Similarly, as for the number of occurrences of replenishment, the replenishment-occurrence frequency calculation unit 123 can convert the number of occurrences of replenishment to a replenishment-operation time by using information on an operation time required for replenishment of each product onto each product shelf. Then, the optimal component-shelf layout extraction unit 124 can extract the component-shelf layout proposal that can reduce the picking-operation time and the replenishment-operation time as compared with the current component-shelf layout or a component-shelf layout proposal that can minimize the total time.
In addition, each of the configuration, the functions, the control unit, the storage unit described above, for example, can be partly or entirely implemented by hardware by being designed with an integrated circuit, for example. Furthermore, a processor can interpret and execute a program achieving each of the functions, so that the configuration and the functions described above, for example, can be implemented by software. Information such as a program for achieving each function, a table, and a file can be placed in a storage device, such as a memory, a hard disk drive, or an SSD (Solid State Drive), or a storage medium, such as an IC card, an SD card, or a DVD.
Number | Date | Country | Kind |
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2013-215163 | Oct 2013 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2014/076490 | 10/3/2014 | WO | 00 |