WO2019112379A1

WO2019112379A1 - Method and system for designing layout of smart factory

Info

Publication number: WO2019112379A1
Application number: PCT/KR2018/015547
Authority: WO
Inventors: 반재만; 임정우; 김두만; 이영훈; 박성현; 김예은; 배찬우
Original assignee: 에스케이 주식회사; 연세대학교 산학협력단
Priority date: 2017-12-08
Filing date: 2018-12-07
Publication date: 2019-06-13
Also published as: KR20190068193A; KR102042318B1

Abstract

A method and a system for designing a layout of a smart factory are provided. A method for designing a layout of a smart factory, according to an embodiment of the present invention, comprises: selecting a layout type of a smart factory; creating blocks and arranging the same in the selected type of layout; and creating lines and arranging the same in the blocks. Accordingly, it is possible to automatically design the layout of a smart factory through systematic standards and algorithms that are not subject to human supervision, thereby ensuring the appropriateness of the design.

Description

Smart Factory Layout Design Method and System

TECHNICAL FIELD The present invention relates to a Smart Factory related technology, and more particularly, to a method and system for automatically designing a Layout of a Smart Factory.

Smart Factory is a factory with high rate of automation that automatically senses the environment and makes intelligent decision-making automatically, thus enhancing the productivity and flexibility of the factory.

Because Smart Factory's intelligent decision making is based on environmental data that includes pre-defined form of production line layout, the first decision in the smart factory construction phase, the basic production system determination and assembly line layout optimization It has a fundamental impact on the performance of the plant.

In other words, optimization of the cell layout design that can improve productivity and flexibility considering automation and logistics is a stepping stone for smart factory to achieve optimum performance.

However, at present, the layout design of the Smart Factory depends on the intuition of the relevant industry experts, and there is a problem that the design based on such a person can not guarantee the adequacy.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and system for automatically designing a layout of a smart factory through systematic standards and algorithms that are not subject to human supervision have.

According to another aspect of the present invention, there is provided a smart factory layout design method comprising: selecting a layout type of a smart factory; A block design step of generating blocks and arranging them in a layout of a predetermined type; And a line design step of creating lines and arranging them in the blocks.

The selection step may be to select one of a plurality of layout types based on the relationship between the number of product types and the amount of production.

The block design step may be to generate blocks using a block generation technique matched to a layout type selected in the selection step among a plurality of block generation techniques.

The block design step may be to divide the layout into a plurality of areas, and allocate areas according to the needs of the blocks to arrange the blocks.

The block design step may be to arrange the blocks so that the cost of transporting the material between the blocks is low.

The block design step may be to arrange the blocks so that the difference between the horizontal and vertical lengths of the blocks is small.

The block design step may be to arrange the blocks so that the total area of the blocks is larger.

The line design stage is to limit the maximum cycle time of the workloads in the workplaces that make up the line, to limit all processes to be allocated to the workplaces, and to calculate the minimum number of workplaces that satisfy the conditions that limit the process' .

The line design phase is to limit the processes that should be assigned to the same workplace, to limit the processes that should not be assigned to the same workplace, and to calculate the minimum number of workplaces that satisfy the conditions that limit the number of devices available at each workplace .

The line design phase may be to change the minimum number of workplaces to equally distribute the work time for the workplaces assigned to the line.

The line design step may be to determine the means of transport to be used in the line, based on at least one of pallet unit transportability, standard of transport, transport speed, transport direction, transport distance, volume of traffic and frequency of transport.

The line design step may be to determine the flow type of the lines according to the determined means of transport.

The smart factory layout designing method according to the present embodiment may further include changing the size of the block based on a result of arranging the lines according to the flow type.

The smart factory layout designing method according to the present embodiment may further include evaluating a designed layout.

According to another aspect of the present invention, there is provided a smart factory layout design system comprising: a collecting unit for collecting information necessary for layout design of a smart factory; And a processor for referring to the collected information to select a layout type of the smart factory, generate blocks and arrange them in a layout of a predetermined type, and generate lines and place the blocks in the blocks.

As described above, according to the embodiments of the present invention, it is possible to automatically design the layout of the smart factory through systematic standards and algorithms that are not subject to human supervision, thereby ensuring the appropriateness of the design.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart provided in the description of a smart factory layout design method according to an embodiment of the present invention;

2 is a diagram illustrating a method of selecting a layout type from information on a product,

FIG. 3 is a block diagram of a block design process,

4 is a diagram illustrating information on inter-block material flow,

5 is a diagram illustrating a result of arranging blocks using an MLA repair model,

FIG. 6 is a view showing a detailed design process,

FIG. 7 is a diagram illustrating a pre-process relationship diagram,

8 is a diagram illustrating a method of assigning work-to-work spaces,

9 is a diagram illustrating a transportation means determination table having a DT structure,

10 is a diagram illustrating a line arrangement table having a DT structure,

11 is a diagram illustrating flow types,

12 is a diagram illustrating buffer size adjustment,

13 is a diagram illustrating batch size adjustment,

14 is a flowchart provided in the explanation of the layout evaluation process,

15 is a block diagram of a layout design system according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a flow chart provided in the description of a smart factory layout designing method according to an embodiment of the present invention.

The smart factory layout designing method according to the embodiment of the present invention is performed by a 'smart factory layout designing system' (hereinafter abbreviated as 'layout designing system') which is a computing system.

Specifically, as shown in FIG. 1, the layout design system analyzes 1) production activities to select an appropriate layout type (S110), 2) design blocks by grouping similar resources (S120) The detailed lines are designed (S130), and evaluated (S140).

Each process will be described in detail below.

1. Selection of layout type (S110)

In order to design a smart factory layout, the layout design system first collects information on the product, and selects the layout type that is optimal for product production through production activity analysis.

Layout types include LL (Linear Layout), FL (Functional Layout), CL (Cellular Layout), and the like.

The information on the product includes the number of part types (Variety) and the amount of production (Parts per hour (Volume)). The layout designing system determines the information &Lt; / RTI >

FIG. 2 shows a method of selecting a layout type from information on a product. As shown in FIG. 2, the layout designing system selects LL when the production amount is higher than the production product number, 2) selects FL when the production product type number is higher than the production amount, and 3) If none of them is dominant, select CL.

2. Block design (S120)

It is possible to design an efficient layout by grouping similar resources and arranging them into blocks rather than arranging the resources used for smart factories individually. Thus, the layout design system generates blocks according to various criteria and effectively arranges them in the layout.

3, the layout design system generates the blocks by performing resource grouping in different ways according to the layout types selected in step S110 (S121), and generates the generated blocks using Mathematical Location (MLA) Allocation) is placed on the layout through the repair model (S122).

2.1 Block creation (S121)

Since the block generation is performed in different ways for each layout type selected in step S110, it will be described below by layout type.

2.1.1 Linear Layout (LL) type block generation

If the layout type selected in step S110 is the LL type, the layout design system classifies the resources into the performance task groups to generate the blocks. The generated blocks can be classified into a preexisting block, a material assembly line block, a main assembly line block, a test line block, a packaging line block, and the like.

2.1.2 Cellular Layout (CL) type block generation

If the layout type selected in step S110 is the CL type, the layout design system generates blocks using a single pass heuristic (SPH) algorithm.

2.1.3 FL (Functional Layout) type block generation

If the layout type selected in step S110 is the FL type, the layout design system generates blocks using a K-means clustering algorithm.

Specifically, the layout design system receives 1) the number K of blocks to be generated and arbitrarily generates K center points of the groups, 2) allocates the resources to groups close to the center point, 3) Is shifted to the average value of the allocated resources, and the process of "2)" and "3)" is repeated until the convergence of the center points is achieved. Thus, resources of similar nature are classified into the same group.

2.2 Block layout (S122)

In order to arrange the blocks generated in step S121, the layout design system collects information to be referred to in the block layout and arranges the blocks using the MLA mathematical model.

2.2.1 Collecting Information for Block Placement

The layout design system collects the information necessary for block layout or receives input from the user.

The information needed for block layout includes block-to-block material flow, unit transportation cost per block distance, required area of blocks, length and length of the plant. The inter-block material flow, as illustrated in FIG. 4, refers to the volume of inter-block material flow.

2.2.2 Mathematical Location and Allocation (MLA) mathematical model

The layout design system fixes the position of a block (such as a scanner line block, a shipping block, etc.), which must be located in a predetermined area, and sets the collected information and the MLA repair model To arrange the blocks.

The MLA repair model is a model that divides a factory into multiple areas and allocates them according to the required area of the blocks. The concrete contents are as follows.

The MLA repair model places the blocks so that the TLC (Total Layout Cost) is minimized. TLC is a formula including MFFC, SRF _whole , and AUF _whole , and the details of each are as follows.

- Material Flow Factor Cost (MFFC) = C _ij × f _ij × d _ij

C _ij : unit transportation cost per distance from block i to block j

f _ij : Material flow from block i to block j

d _ij : diagonal distance from block i to block j

a _ijk : the value of 1 if block k is located in the jth column of the ith row

L: Length of the plant

W: The length of the factory

The conditions for a _ijk are as follows: 1) a maximum of one block can be allocated to the factory area (ie, two or more blocks can not be allocated in one area); 2) And 3) the total sum of the block areas does not exceed the area of the factory.

The MFFC corresponds to the cost of transporting materials, with smaller values being preferred.

- Shape Ratio Factor (SRF) _whole =

SR _i : Shape Ratio (SR) of block i

P _i : the perimeter of block i

A _i : Required area of block i

The SRF has a value of 1 as the block is closer to a square, and the larger the length difference between the horizontal and the vertical, the larger the value becomes. A value close to 1 is preferred.

- Area Utiliization Factor (AUF) _whole =

ΣA _i : total required area of all blocks

Total Blank Area of layout (TBA): Area without block allocation

The AUF represents the utilization rate for the total area of the plant, with a value close to 1 being preferred.

FIG. 5 illustrates the result of arranging the blocks using the MLA repair model.

3. Detailed design (S130)

When the block design of step S120 is completed, the layout design system performs detailed design for each of the blocks.

Specifically, the layout design system generates lines for the blocks designed in step S120 (S131), determines transportation means for transportation between the generated lines (S132), generates (S133), and adjusts the details (S134)

3.1 Line Generation (S131): Line Balancing

A line is a set of connected workspaces with the same cycle time. In other words, workplaces are grouped in a line and placed in a block.

The most important consideration in line generation is line balancing. To do this, the layout design system must determine the number of lines and the minimum number of workplaces per line, and evenly allocate work between the workplaces.

3.1.1 Collecting Information for Line Balancing

Line balancing is designed to maximize line efficiency while minimizing idle time for each workplace, maximizing per-person productivity and maximizing production within a given number of people, under conditions that achieve target production.

The layout design system determines the number of lines and collects information for line balancing.

Information for line balancing should be made in the workplace, such as information on required processes, post-process relationships, information on work time per process, information on equipment used per process, Information about processes that should not be done in the same workplace, and information about processes that should not be done in the same workplace.

The process posterior relationship diagram is a diagram showing a posterior relationship between the processes as illustrated in FIG.

3.1.2 Calculate the minimum number of workplaces per line

The layout design system calculates the minimum number of workplaces per line using the following algorithm.

c _ik : cost constant, Nc _ik? c _{(i, k + 1)} ; k = 1, ... , K-1

X _ik : 1 if process i is assigned to workplace k, 0 if not,

t _i : work time per process

IP = {(u, v): task u must precede v}

ZS: set of processes to be assigned to the same workplace

ZD: set of processes that should not be assigned to the same workplace

ZM _im : 1 if equipment m is used in process i, otherwise 0

Y _km : 1 if machine m is used in workstation k, 0 if not,

MaxM: Maximum number of devices available for each workshop

This algorithm limits the maximum cycle time of the workload in each workplace, constrains all processes to be allocated to the workplaces, constrains the process's posterior relations, constrains the processes that should be assigned to the same workplace, Limit the processes that should not be done, limit all equipment to workplaces, limit the number of equipment available in each workplace, and calculate the minimum number of workplaces per line where the minimum cost is estimated.

3.1.3 Equal assignment of work between workshops

The layout design system equally distributes work time for the workplaces assigned to the line. In other words, the layout design system can be said to distribute the idle time equally among the workplaces. FIG. 8 illustrates a process of equalizing the workload among the workplaces.

In order to equalize the workloads, the layout design system uses the following algorithm after changing the minimum number of workload calculation algorithms per line described above.

The Index k in the algorithm for calculating the minimum number of workplaces per line described above is calculated by Index k = 1, ... , K ^* . K ^* is the minimum number of workpieces per line.

3.1.4 Detailed adjustments reflecting other issues

The layout design system can adjust the work assignment among the work sites in consideration of the change of the work time according to the skill level of the worker, the change of the work time due to the process merge / separation, and the like.

3.2 Determination of transportation (S132)

Transportation methods include Conveyor, AGV, Cart, Overhead Hoist Transfer (OHT) Vehicle, Overhead Crane, and Robot. Generally, because they produce a product that undergoes a similar manufacturing process, it often uses only one type of transportation.

The layout design system determines a transportation means by using a transportation determination table having a DT (Decision Tree) structure as shown in Fig.

In addition to the maximum horizontal / vertical / height and maximum weight of the object to be transported, the maximum transport speed, the transport direction, the maximum transport distance, and the transport amount and frequency , Rotation angle, transport accuracy and flexibility, temperature, vibration, noise, stability, energy used, purchase and maintenance costs, and other equipment constraints.

3.3 Line arrangement (S133)

The line arrangement is a step of positioning the generated lines in the block. The layout design system determines the flow type of the lines according to the transportation means determined in step S132. The line arrangement table of the DT structure for determining the flow type according to the transportation means is illustrated in Fig. 10, and several flow types that can be determined are illustrated in Fig.

If the size of the block is not proper as a result of arranging the lines according to the flow type, the layout design system can return to the block generation (S121) and regenerate the block to a proper size.

3.4 Details adjustment (S134)

After the line arrangement in step S133, the layout design system determines the buffer size between jobs, the batch size of the materials transported by the transportation means determined in step S132, ergonomic work site design, The details of the lines can be adjusted based on balancing adjustments and flexibility in product changes.

Specifically, in the case of adjusting the buffer size, the layout design system adds a buffer of a bottleneck process (BN) or a non-bottleneck process (NBN) close to the bottleneck process, as shown in FIG. As a result, the effect of increasing the production amount can be shown.

Further, as shown in Fig. 13, the layout design system can appropriately adjust the batch size, thereby improving the work speed and equipment efficiency.

4. Evaluation

When the design for the smart factory layout is completed in steps S110 to S130, the layout design system evaluates the designed layout (S140). 14 is a flowchart provided for explanation of the layout evaluation process.

As shown in FIG. 14, when creating alternative candidate layouts for the current smart factory layout through steps S110 to S130, the layout design system performs a drawing-based evaluation on the designed alternative candidate layouts (S141).

Next, the layout design system selects some (2 to 3) alternative candidate layouts as good candidate layouts based on the evaluation result in step S141 (S142).

In step S143, the layout design system performs evaluation based on the computer simulation on the best candidate layouts selected in step S142, and selects one candidate layout as the final alternative layout based on the evaluation result in step S144.

Thereafter, if the smart factory layout is changed according to the final alternative layout selected in step S144 (S145), the layout design system performs on-site evaluation of the changed layout (S146).

If the on-scene evaluation score is equal to or greater than the reference value (S147-Y), the layout design system maintains the layout. On the other hand, if the on-scene score is less than the threshold (S147-N), the layout design system regenerates alternative candidate layouts for the current smart factory layout and performs subsequent procedures.

5. Layout design system

15 is a block diagram of a layout design system according to another embodiment of the present invention. A layout design system according to an embodiment of the present invention includes a communication unit 210, a display 220, a processor 230, an input unit 240, and a storage unit 250, as shown in FIG. to be.

The communication unit 210 receives information necessary for layout design / evaluation from an external device or an external network, and the input unit 240 receives information necessary for layout design / evaluation from the user.

The processor 230 designs the layout according to the smart factory layout designing method shown in Fig. 1, and evaluates the layout according to the smart factory layout evaluation method shown in Fig.

The storage unit 250 stores information necessary for layout design / evaluation, and provides a storage space necessary for the processor 230 to perform layout design / evaluation.

Therefore, the communication unit 210, the input unit 240, and the storage unit 250 function as information collection means for collecting information necessary for layout design / evaluation.

It goes without saying that the technical idea of the present invention can also be applied to a computer-readable recording medium having a computer program for performing the functions of the apparatus and method according to the present embodiment. In addition, the technical idea according to various embodiments of the present invention may be embodied in computer-readable code form recorded on a computer-readable recording medium. The computer-readable recording medium is any data storage device that can be read by a computer and can store data. For example, the computer-readable recording medium may be a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical disk, a hard disk drive, or the like. In addition, the computer readable code or program stored in the computer readable recording medium may be transmitted through a network connected between the computers.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present invention.

Claims

Selecting a layout type of the smart factory;

A block design step of generating blocks and arranging them in a layout of a predetermined type; And

A line design step of creating lines and arranging them in blocks.
The method according to claim 1,

In the selection step,

Wherein one of a plurality of layout types is selected based on a relationship between the number of product types and a production amount.
The method of claim 2,

In the block design step,

Wherein the blocks are generated by using a block generation technique matched to a layout type selected in a selection step among a plurality of block generation techniques.
The method according to claim 1,

In the block design step,

Wherein the layout is divided into a plurality of areas, and the blocks are arranged by allocating areas according to the necessity of the blocks.
The method of claim 4,

In the block design step,

Wherein the blocks are arranged such that the cost of material transportation between the blocks is reduced.
The method of claim 4,

In the block design step,

Wherein the blocks are arranged such that the difference between the horizontal and vertical lengths of the blocks is smaller.
The method of claim 4,

In the block design step,

Wherein the blocks are arranged such that the total area of the blocks is larger.
The method according to claim 1,

In the line design stage,

Wherein the minimum number of workplaces satisfying the condition that limits the maximum cycle time of the workload in the workplaces constituting the line, restricting all the processes to be allocated to the workplaces, and constraining the sequential relation of the processes is calculated, Layout design method.
The method of claim 8,

In the line design stage,

Constraining processes that should be assigned to the same workplace, constraining processes that should not be assigned to the same workplace, and calculating a minimum number of workplaces satisfying a condition that constrains the number of devices available in each workplace. Layout design method.
The method of claim 8,

In the line design stage,

Wherein the minimum number of workplaces is changed so as to distribute the working time equally to the workplaces assigned to the line.
The method according to claim 1,

In the line design stage,

Wherein said determining means determines the transportation means to be used in the line based on at least one of pallet unit transferability, standard of transportation, transportation speed, transportation direction, transportation distance, transportation amount and transportation frequency.
The method of claim 11,

In the line design stage,

And determine a flow type of the lines according to the determined transportation means.
The method of claim 12,

And changing the size of the block based on a result of arranging the lines according to the flow type.
The method according to claim 1,

And evaluating the designed layout. &Lt; Desc / Clms Page number 19 >
A collection unit for collecting information necessary for layout design of the smart factory; And

And a processor for referring to the collected information to select a layout type of the smart factory, to generate blocks and to arrange the blocks in a layout of a predetermined type, and to create lines and to arrange the blocks in the blocks. Design system.