JP7182885B2 - Operation start condition conversion device and operation start condition conversion method - Google Patents

Description

The present invention relates to an operation start condition conversion device for creating an operation plan in a production system.

In a production system in which a plurality of manufacturing apparatuses and works (products) produced by each manufacturing apparatus are transported by an automatic guided vehicle (AGV), for example, as disclosed in Patent Document 1, the manufacturing apparatus A method is known in which the production order of works to be produced is planned in advance, and the operation of the AGVs is controlled so that the arrival order of the AGVs requiring the works is the same as the production order of the works in the manufacturing equipment. . Here, a product number is assigned to each product conveyed by the AGV, and the information on the work necessary for the product number is determined in advance.

In addition, in Patent Document 2, the margin until the completion delivery date of the product being manufactured is calculated, the priority of manufacturing is determined based on the margin, and the manufacturing equipment and the AGV are operated based on the priority. A method for determining an indication is disclosed.

JP 2009-143716 A JP 2008-250826 A

The operation management method disclosed in Patent Document 1 is based on the premise that the production order of products and the order of the manufacturing apparatuses that the AGV circulates are fixed. Therefore, when the production order of the products is not fixed, there is a problem that the order of AGV tours becomes unknown. In other words, even if the order of AGVs arriving at each manufacturing equipment is fixed, if the order of AGVs to the manufacturing equipment is not fixed, the waiting time of the manufacturing equipment depends on the cyclic order of each AGV. increase, etc., and the operation plan may collapse.

In the operation management method disclosed in Patent Document 2, the priority is calculated and the next work is determined online. There is a problem that computational resources increase. In addition, since the decision is made based only on the current priority, it is impossible to make a global decision, and there is a possibility that the operation plan as a whole will be wasteful.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and provides an operation start condition conversion apparatus that creates an operation plan that suppresses the computational load required to determine whether to start operation of each piece of equipment in a production system. With the goal.

The operation start condition conversion device according to the present invention converts a plurality of works included in an operation schedule in which timings of a plurality of works to be performed by each facility of a production system for producing a product are designated by time to works with different priorities. a work resource classification unit that classifies the work into resources; and a work type classification unit that classifies the plurality of works into direct work on the product and indirect work on the product including setup change including change of supplied parts or replacement of tools; a product assembly sequence condition setting unit that sets completion of work with low priority among the direct work on the product as a first operation start condition; a parts supply condition setting unit that sets the completion of the work to be received as a second operation start condition, wherein the operation schedule is specified by an event including the completion of the work according to the first and second operation start conditions. The operation plan is converted into an operation plan, and input to the control system that operates the production system so as to execute the operations with the highest priority among the operations for which the operation start conditions have been satisfied.

According to the present invention, the operation schedule specified by the time is converted into the operation plan specified by the event according to the first and second operation start conditions. , it is possible to generate an operation plan capable of operating the production system according to the operation schedule.

It is a figure which shows an example of a driving schedule typically. BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the structure of the production system provided with the driving|operation start condition conversion apparatus of Embodiment 1 which concerns on this invention. It is a schematic diagram showing an example of a job shop. It is a figure which shows an example of a driving schedule typically. FIG. 4 is a diagram schematically showing a software architecture when giving operation instructions to each piece of equipment based on the operation plan output from the operation start condition conversion apparatus of Embodiment 1 according to the present invention; BRIEF DESCRIPTION OF THE DRAWINGS It is a functional block diagram which shows the structure of the driving|operation start condition conversion apparatus of Embodiment 1 which concerns on this invention. FIG. 10 is a diagram showing the result of classifying the work of each piece of equipment in the operation schedule into work resources; It is a figure which shows an example of the restrictions added by the product assembly order condition setting part. It is a figure which shows an example of the restrictions added by the components supply condition setting part. 4 is a flow chart showing a method for converting a driving start condition according to Embodiment 1 of the present invention; It is a figure which shows an example of the interlock contained in the control program of equipment. FIG. 4 is a block diagram showing the configuration of a production system provided with an operation start condition conversion device according to Embodiment 2 of the present invention; FIG. 7 is a functional block diagram showing the configuration of a driving start condition conversion device according to Embodiment 2 of the present invention;

<Embodiment 1>
The object of application of the present invention is a job shop production system using an AGV (Automatic Guided Vehicle). AGVs are vehicles that automatically transport products and parts within a factory. Recently, AGVs that can move to any location within a factory have been developed using self-localization and map creation technologies such as Slam (Simultaneous Localization and Mapping). being developed.

A job shop is a production facility that has a plurality of fixed functions, such as a product or part input function, processing or assembly work, and product delivery, and performs some work independently. A job shop production system using AGVs is a production system in which AGVs transport products between job shops and the products are completed via a plurality of job shops. Hereinafter, production equipment and AGV are collectively referred to as equipment. There are a plurality of job shops that have equivalent functions, and there is a degree of freedom in selecting which job shop will carry out the work on the product.

In order to operate the job shop production system efficiently, the operation schedule of AGV and production equipment is important. A production system schedule is generally created based on operating capacity information such as the production capacity of the manufacturing equipment, the work time of the production equipment in each operation instruction, and the travel time of the AGV. Based on the driving ability information, an optimal driving schedule is created for order data including the types and numbers of products to be manufactured.

Here, the objective function judged to be optimal includes a short production time in the entire production system, a short total operating time of each production equipment, and a short time during which work-in-progress products are in progress. In addition, if the order includes delivery date information, priority information, or both, constraints such as compliance with delivery date and priority may be included.

The delivery date information may be expressed by the production completion time in the factory instead of the delivery date to the customer. By appropriately setting the operation schedule, it is possible to increase the operation rate of the equipment, shorten the operation time, and reduce the production cost.

Since the creation of an operation schedule in a job shop production system is a large-scale optimization problem, it is common practice to handle operation capacity information such as the working time of production equipment and the travel time of AGVs as fixed values. Therefore, the operation schedule can be uniquely described by when the production equipment and the AGV will perform what kind of work. If the objective function does not include the work-in-progress time of the work-in-progress, it can be described only by the order of operation instructions. FIG. 1 schematically shows an example of a driving schedule.

FIG. 1 shows a schedule of operations in manufacturing apparatuses 1-3 and movements of AGVs 1-3. After that, AGV1 moves with movement 1-2. Also, the AGV 2 performs work 3-2 on the work carried by movement 2-1. In addition, the AGV 3 moves the work for which the work 1-1 has been completed by the movement 3-2.

Such an operation schedule is created based on the operation time of the production equipment and the operation capability information such as the travel time of the AGV, but such an operation schedule cannot actually operate the production system. This is because the operating time information of the actual production equipment and the travel time of the AGV contain errors. In addition, events that cannot be predicted at the time the schedule is created, such as work errors in production equipment due to errors in input parts, avoidance of other vehicles and traffic jams during movement of the AGV, etc., also occur. For these reasons, it is not possible to strictly operate an operation schedule specified by time. Therefore, it is necessary to convert a time-specified operation schedule into an operation plan conditional on the completion of work, such as executing an operation instruction based on the completion of the work.

Moreover, in actual operation, it is desirable to combine local optimization and global optimization. As an example of local optimization, assume a situation where both transfer work between the AGV and the job shop and processing or assembly of parts within the job shop are executable.

For example, in consideration of increasing the operating efficiency of other equipment, it may be better to give priority to the transfer work with the AGV over the work in the job shop. Specifically, if a certain job shop prioritizes work on a product to be delivered to a job shop that is different from the next destination of the AGV, the transfer work to the AGV will not be completed, and the start of AGV movement will be postponed. As a result, the operating efficiency at the job shop, which is the next destination of the AGV, is lowered. In this way, simple optimization can be achieved with only local situation information such as the current state in the job shop. Such optimization performed using only spatially or temporally local information such as information within the job shop or the current state within the job shop is referred to as local optimization.

Local optimization has the advantage that it requires less computational resources for decision making and can be implemented in the controller of the manufacturing equipment. It is often realized by setting the priority of the work in advance, and executing the work with the highest priority among the works for which the operation start conditions are satisfied.

Global optimization is optimization performed on the basis of the entire factory or the entire operating schedule, or both. For example, in order to give priority to the production of products whose delivery date is near, there is a method of suspending the production of other products and vacating production facilities. Another method is to create an operation schedule so that the same work can be performed continuously so as to reduce setup changes of manufacturing equipment.

Global optimization requires a wide range of information and judgment criteria for optimization, so it is often processed by equipment that has a dedicated function such as a scheduler and is separate from the operation of the production system. In the process, for time-defined driving schedules, conventional and widely studied solutions to the scheduling problem can be applied.

In actual operation, delays in work will occur due to the operation schedule. It is preferable to apply local optimizations, such as by not waiting for unfinished work to complete.

<Configuration of production system>
FIG. 2 is a block diagram showing the configuration of a production system 100 equipped with an operation start condition conversion device 20 according to Embodiment 1 of the present invention. As shown in FIG. 2, the production system 100 includes a scheduler 10, an operation start condition conversion device 20, an MES (Manufacturing Execution System) 30, a plurality of manufacturing devices 41, 42 to 4n, and a plurality of AGVs 51 to 5m. I have it.

The scheduler 10 creates and outputs an operation schedule for the production equipment and the AGV based on the order data and the operation capability information of the production system input from a data input device (not shown). For example, as shown in FIG. 1, this operation schedule is expressed in the form of what kind of work each piece of equipment does at what time.

The operation start condition conversion device 20 converts the operation start condition from the designation by time to the designation by an event such as the completion of work for the operation schedule input from the scheduler 10, and outputs it as an operation plan that can be used in an actual system. do. The operation start condition conversion device 20 is configured by, for example, an arithmetic processing device including a storage unit 21, a processing unit 22, and the like.

The MES 30 is a control system that transmits operation instructions to each facility such as the manufacturing apparatuses 41 to 4n and the AGVs 51 to 5m based on the operation plan input from the operation start condition conversion device 20. FIG.

Manufacturing apparatuses 41 to 4n and AGVs 51 to 5m that have received operation instructions from the MES carry out operations based on preset operation programs. Although the MES 30 and each facility are directly connected in FIG. 2, a computing device for relay or integrated management and a dedicated controller may be arranged between the MES 30 and each facility.

<Configuration of job shop>
FIG. 3 is a schematic diagram showing an example of a job shop. The job shop shown in FIG. 3 is equipped with two sets of robots, workbenches, parts feeders, and one processing machine. Robots RB1 and RB2 transfer products between AGVs 1 and 2 and workbenches WS1 and WS2, respectively, assemble parts supplied from parts feeders PS1 and PS2 into products, and process machines. Perform the input work of the product to the MC.

Two sets of workbench and parts feeder are provided, and the AGV standby location differs depending on the robot, so work on the workbench and transfer work to the AGV can be performed independently by each robot. On the other hand, since there is only one processing machine in the job shop, it is shared by two robots.

Robots RB1 and RB2 are well-known vertically articulated industrial robots. The workbenches WS1 and WS2 are places where the robots RB1 and RB2 work, respectively, and are equipped with jigs and the like for fixing the product, but illustration thereof is omitted.

The component suppliers PS1 and PS2 supply components to the robots RB1 and RB2, respectively, and have functions such as pallet changers that can change the types of components to be supplied. In addition, the processing machine MC has a function of automatically changing tools.

AGV1 carries products PD1 and PD2, and AGV2 carries products PD3 and PD4. Note that FIG. 3 is an example of a job shop, and is not limited to this form.

<Operation schedule and operation plan>
FIG. 4 is a diagram schematically showing an example of an operation schedule output by the scheduler 10 (FIG. 2). The horizontal axis represents time, blocks in each work resource represent that work is being done in a period corresponding to its length, and what kind of work is performed at what time for each manufacturing device. or is expressed by the type of block. The data includes the work type and work start time of each work. Further, it may include additional information specifying work parameters and the like, work time, and the like.

The operation schedule shown in FIG. 4 is an operation schedule corresponding to the job shop shown in FIG. represents time.

It should be noted that the work in each manufacturing apparatus is assigned a serial number to the block in order of work, and for example, 1 to 6 are assigned to the processing machine MC. Also, in each block, different types of work are indicated by different hatching. , with different hatching. This serial number is also attached to FIGS. 7 and 8 to 10 in order to represent a series of operations in each manufacturing apparatus.

The processing machine MC includes tool changing work and processing work, the parts feeders PS1 and PS2 only work to change the supplied parts, and the robots RB1 and RB2 respectively transfer work to the AGV, This includes loading into the processing machine and assembly on the workbench.

In any manufacturing apparatus, the work is arranged in chronological order, and the operation schedule is such that the start of operation of each work is designated by time. By inputting such an operation schedule specified by time into the operation start condition conversion device 20 and converting the operation start condition specified by time into an operation start condition specified by an event such as completion of work , convert it into an operation plan that can be operated in an actual system.

FIG. 5 shows the software architecture of the MES 30, which inputs the operation schedule shown in FIG. It is a figure represented typically.

The operation plan output from the operation start condition conversion device 20 is represented by the work content, task number, and work task. Work on each piece of equipment is classified as a work resource based on priority, type, and the like. A task number is a number uniquely determined within each work resource. The operation start condition is a condition when the MES 30 transmits the work instruction included in the work task to each piece of equipment.

As shown in FIG. 5, a task queue is held for each work resource, and work tasks included in the operation plan are taken out in order of task numbers. For example, when the executed final task number is 1 and the work task being executed is empty (NULL), the work task at the head of the task queue, such as the work resource for changing the supplied parts in the parts feeder PS1, That is, the work task No. 2 is taken out, but if the operation start condition of the work task is not met, the work task is set as a guarded work task, and the guarded work task number is set to 2. On the other hand, when the operation start condition of the work task taken out from the task queue is satisfied, the work task is set as the running task, and the running task number is set to 2.

A work task that has become an in-progress task is an in-progress task until it sends its work content to the corresponding equipment and receives a work completion from the equipment. Discarded and empty. Then, the executed final task number is updated to 2.

The operation start condition is specified by the work resource and task number, and the condition is assumed to be satisfied when the executed final task number of the specified work resource is greater than or equal to the specified task number. do. For example, in FIG. 5, in the work resource of the AGV1 transfer work of the robot RB1, the operation start condition of the work task No. 3 taken out from the task queue is the work task No. 3 in the work resource of the processing machine loading work of the robot RB1. If the executed final task number of the work resource for the processing machine input work of the robot RB1 is 3, the work task number 3 of the work resource for the AGV1 transfer work of the robot RB1 is , the working task No. 3 is determined to be the task being executed, and the task number being executed is changed from NULL to 3.

Further, when the operation start condition of the work task taken out from the task queue is not met, it means that the executed final task number of the designated work resource is greater than the designated task number. Even if the operation start condition is not satisfied and the work task is guarded, if the work of the designated work resource progresses and the operation start condition is satisfied, the guarded work task becomes an active task. . Also, if there is a guarded work task, no work task is taken from the task queue even if the task being executed is empty.

Note that the processing method described above is only an example, and the application of the operation start condition conversion device 20 of the present embodiment is not limited to this. It would be nice if it could be set properly. Here, "appropriate" means that in a production system that executes an operation plan according to a predetermined rule, global optimization can be performed with few restrictions, and the required work order can be maintained.

As described above, the software architecture shown in FIG. 5 inputs the operation schedule output from the scheduler 10 (FIG. 2) to the operation start condition conversion device 20, and converts the operation start condition specified by time into the operation start condition. Work instructions are given based on the operation plan obtained by converting the operation start conditions specified by events such as completion. The operation start condition conversion device 20 will be described below.

<Structure of operation start condition conversion device>
FIG. 6 is a functional block diagram showing the configuration of the operation start condition conversion device 20. As shown in FIG. As shown in FIG. 6, the operation start condition conversion device 20 receives data output from the scheduler 10 (FIG. 2) via a data input unit 23, which is a functional unit responsible for inputting data to the operation start condition conversion device 20. In addition to the operation schedule D1, product data D2 and work data D3 are input and stored in the storage unit 21. FIG. Note that the data input unit 23 may be included in the storage unit 21 .

The product data D2 is data relating to the manufacturing method of the product, such as the assembly order of the product to be manufactured and the part type. The work data D3 is data related to the work performed by each manufacturing apparatus, and is used to distinguish whether each work performed by each manufacturing apparatus is a direct work related to product manufacturing or an indirect work related to parts supply or setup change. contains information on These data are basically input to the storage unit 21 when constructing the production system 100, and updated and added when the production system 100 is changed.

<Operation of operation start condition conversion device>
<Classification in the work resource classification part>
The work resource classification unit 221 included in the processing unit 22 reads the operation schedule D1, the product data D2, and the work data D3 from the storage unit 21, and cancels the operation start condition specified by the time in the operation schedule D1. Then, the work of each facility included in the operation schedule D1 is classified as work resources by priority. Since a job shop can perform multiple different jobs, prioritizing job types can provide local optimization.

In order to set a priority for work in each facility in the operation schedule, the work resource classification unit 221 classifies the work in each facility in the operation schedule into work according to priority. For example, transfer work between the production equipment and the AGV is given the highest priority, and other work is given lower priority. Classify. However, even if the work is included in one piece of production equipment, it is classified as a separate work resource if the work can be done independently of each other.

FIG. 7 shows the result of classifying the work of each piece of equipment in the operation schedule shown in FIG. It shows that you are working in the period corresponding to the length.

Also, in FIG. 7, the work described at the top of each production facility is represented as having a higher priority. That is, in the processing machine MC, tool replacement has a higher priority than processing, and in the robots RB1 and RB2, the transfer work to the AGV, the loading work to the processing machine, and the assembly work on the workbench are given priority in this order. set high.

Among the work resources in each production facility classified in this way, for example, for the processing machine MC, the work Nos. 1, 4, and 6 correspond to tool change, and the work Nos. 2, 3, and 5 correspond to tool change. It corresponds to processing. Also, regarding the robot RB1, the operations Nos. 1 and 12 correspond to the operations of transferring to the AGV1, and the operations Nos. 2, 6, 7 and 11 correspond to the operations of loading into the processing machine MC. Work Nos. 3, 4, 5, 8, 9 and 10 correspond to assembly work on the workbench WS1. In addition, regarding robot RB2, operations 1 and 10 correspond to transfer operations to AGV2, operations 8 and 9 correspond to input operations to processing machine MC, and operations 2 to 7 The work corresponds to assembly work on the workbench WS2.

Note that applying all local optimizations based on priority may affect global optimization. Therefore, in the processing after the work type classification unit 222, the operation start condition is set so as not to affect the global optimization.

<Classification by the work type classification section>
The work type classification unit 222 classifies the work resources classified by the work resource classification unit 221 into work types based on the work data D3. This classification is divided into "(a) direct work on the product" and "(b) indirect work on the product such as setup change". "(a) Work directly on the product" is work in contact with the product, such as processing or assembly of the product, or transfer of the product. "(b) Indirect work on products such as setup change" refers to so-called setup change work such as changing supply parts or replacing tools, which is related to the manufacture of multiple products, but is directly related to the product. It is work that does not touch. In the example of FIG. 7, "(a) work directly on the product" is the "processing" work by the processing machine MC and all the work by the robots RB1 and RB2. The "(b) indirect work for products such as setup change" is a "tool change" work in the processing machine MC and a "supplied part change" work in the parts feeders PS1 and PS2.

<Addition of restrictions in the product assembly order condition setting part>
The product assembly order condition setting unit 223 adds restrictions on the work order of manufacturing each product to the “(a) direct work on products” classified by the work type classification unit 222 . That is, restrictions on starting operation are added to the work that satisfies the following conditions in the operation schedule. Specifically, the work to which the restriction is added is the work classified as "(a) work directly on the product", and the work with lower priority is performed in the same equipment for the same product first. It is the work being done. The additional constraint is that the preceding work must be completed, and if the preceding work is work for multiple products, even one product , to add constraints. The restrictions on the operation start added by the product assembly sequence condition setting unit 223 are called first operation start conditions.

FIG. 8 is a diagram showing an example of the constraints added by the product assembly order condition setting unit 223 applied to the work resources classified in FIG. An additional constraint is the completion of assembly operations on robots RB1 and RB2.

In order to explain the added constraints, in FIG. 8, for the robot RB1, for the work Nos. 3, 4, 5, 8, 9 and 10 corresponding to the assembly work on the workbench WS1, , a, b, c, d, e, and f, respectively, which are the IDs of the products targeted in the respective operations. In addition, work Nos. 2 and 6, which correspond to work to be loaded into the processing machine MC, are given a product ID of d, and work Nos. 7 and 11 are given a product ID of b. In addition, since the work No. 12 corresponding to the transfer work to the AGV 1 targets the products with IDs a to f, the IDs a to f are attached.

Similarly, for the robot RB2, g, h, i, j, k, and l are assigned as product IDs to operations Nos. 2 to 7, which correspond to assembly operations on the workbench WS2. The work Nos. 8 and 9, which correspond to the input work to the MC, are given h as the product ID. Also, since the work No. 10 corresponding to the transfer work to the AGV 2 targets the products with IDs g to l, g to l are added as IDs.

In FIG. 8, arrows are used to represent constraints. In other words, it indicates that completion of the work indicated by the arrow is a condition for starting the operation of the work to which the arrow reaches.

Specifically, in the loading operation of the robot RB1 to the processing machine MC, when loading the product with the ID b, which is the target of the work No. 7, into the processing machine MC, the work table WS1 with the lower priority is used. In the assembly work of No. 5, it is added as a constraint that the work for the product with ID c, which is the object of work No. 5, has been completed.

In addition, in the transfer work of the robot RB1 to the AGV1, when transferring the products with IDs a to f that are the target of the 12th work, in the input work to the processing machine MC with a lower priority, The processing of the product with ID b, which is the target of work No. 11, has been completed, and the work on the product with ID f, which is the target of work No. 10, in the assembly work on workbench WS1 has been completed. As a constraint, we have added that

Similarly, in the input work of the robot RB2 to the processing machine MC, when the product with the ID h, which is the target of the work No. 8, is input to the processing machine MC, the assembly on the workbench WS2 with the lower priority is performed. In the work, the fact that the work for the product with the ID of l, which is the object of work No. 7, has been completed is added as a constraint.

<Addition of constraints in the part supply condition setting section>
The parts supply condition setting unit 224 adds a constraint such as waiting for the start of the changeover to the “(b) indirect work to the product such as changeover” classified by the work type classification unit 222 . That is, a constraint on starting operation (second condition for starting operation) is added to the work that satisfies the following conditions in the operation schedule. The work to which the constraint is added is the work classified as "(b) indirect work to the product such as setup change", and the work that is performed in advance using the things that will be changed in the setup work, In other words, it is the work performed in advance that is affected by the setup change. An additional constraint is that the preceding work is completed.

FIG. 9 is a diagram showing an example of the constraints added by the parts supply condition setting unit 224 applied to the work resources classified in FIG. Completion of assembly work in robots RB1 and RB2 and completion of machining work in machine MC are added as constraints.

In FIG. 9, arrows are used to represent constraints. In other words, it indicates that completion of the work indicated by the arrow is a condition for starting the operation of the work to which the arrow reaches.

Specifically, when changing the parts to be supplied by the parts feeders PS1 and PS2, the parts used in the assembly work of the robots RB1 and RB2 are changed, respectively. It is added as a constraint that the work No. 5 and the work No. 5, which is the assembly work on the workbench WS2, have been completed. However, in each of the component feeders PS1 and PS2, there is no previously completed work for the first work for changing supplied parts, so no restriction is added.

In addition, in the tool exchange of the processing machine MC, the fact that work No. 3 and work No. 5, which are lower priority machining works, have been completed is added as a constraint.

As described above, through processing in each functional block in the operation start condition conversion device 20, work resources are classified and work types are classified, and the classified "(a) direct work on products" and An operation start condition can be added to "(b) indirect work on the product such as setup change".

<Operation start condition conversion method>
A method for converting the operation start condition in the operation start condition conversion device 20 of Embodiment 1 according to the present invention described above will be described with reference to the flowchart shown in FIG. 10 .

First, the work resource classification unit 221 cancels the operation start condition specified by the time in the operation schedule D1 read from the storage unit 21 (step S1), and classifies the work included in the operation schedule into work resources with different priorities. (step S2).

Next, in the work type classification unit 222, "(a) direct work on the product" and "(b) indirect work on the product such as setup change" are classified based on the work data D3 for the classified work resource. (step S3).

Next, in the product assembly sequence condition setting unit 223, among the works classified as "(a) direct work on the product", the completion of the preceding work with low priority is restricted to the start of operation (first 1 operation start condition) (step S4).

Next, in the parts supply condition setting unit 224, in the work classified as "(b) indirect work to the product such as setup change", the completion of the preceding work affected by the setup change is operated. It is added as a start restriction (second operation start condition) (step S5).

<Addition of interlock>
In order to avoid interference between the equipment that constitutes the production system with respect to the operation start condition added by the operation start condition conversion device 20, an interlock is included as a constraint incorporated in the equipment control program.

FIG. 11 is a diagram showing an example of interlocks included in the equipment control program applied to the work resources classified in FIG. For example, the robots RB1 and RB2 can perform the work of loading the product into the processing machine MC only when the processing machine MC is in a stopped state, i.e., when the processing machine MC is not performing tool changing or processing work. In other words, the tool change and machining operations in the processing machine MC can be executed only when the robots RB1 and RB2 are not in the process of loading products into the processing machine MC. For example, in FIG. 10, work No. 2, which is the work of loading a product into the processing machine MC by the robot RB1, cannot be performed until work No. 1, which is the work of changing tools in the processing machine MC, is completed. The work No. 2, which is the processing work in the processing machine MC, cannot be performed until after the work No. 2, which is the work of loading the product into the processing machine MC by the robot RB1, is completed.

In addition, the product assembly work by the robots RB1 and RB2 can be executed only when the part supply change work is not being executed by the parts supply machines PS1 and PS2 in order to confirm that the parts for the assembly work are supplied. be. For example, in FIG. 10, work No. 8, which is product assembly work in robot RB1, cannot be performed until work No. 2, which is part supply change work in parts feeder PS1, is completed.

By combining the interlock included in the equipment control program and the operation plan in which the constraints are set by the product assembly order condition setting unit 223 and the parts supply condition setting unit 224 of the operation start condition conversion device 20, the job The shop production system can realize operation according to the operation schedule output by the scheduler 10 .

It should be noted that the work start time may differ from the operation schedule output by the scheduler due to the release of the time-specified operation start condition and the addition of interlocks and restrictions as described above. Also, depending on the situation, there is a possibility that the work order within each device will also be changed. However, constraints for maintaining global optimization, such as manufacturing order such as which product to manufacture from, timing of setup change, etc., are observed.

In addition, in the present embodiment, an example of adding restrictions within one job shop has been described, but the addition of restrictions may be implemented in the entire factory, or the assembly of the product may be carried out across a plurality of job shops. An additional constraint may be the completion of work at another job shop, as it may be enforced.

As described above, the operation start condition conversion device 20 according to the first embodiment of the present invention includes the work resource classification unit 221 that classifies the work included in the driving schedule into work resources with different priorities, and A work type classification unit 222 that classifies whether it is direct work to the product or indirect work to the product such as setup change, and the completion of the work with low priority among the direct work to the product is set as a constraint on the start of operation of the product An assembly sequence condition setting unit 223 and a parts supply condition setting unit 224 that sets the completion of work affected by setup change among indirect works for products as a constraint on the start of operation, and the operation schedule is set by events. Convert to the specified operation plan and output. As a result, it is possible to generate an operation plan that allows operation of the production system in accordance with the operation schedule while suppressing the calculation load necessary for determining the operation start condition.

<Embodiment 2>
In an actual production system, disturbances such as work failures and work delays occur, so the system cannot be operated according to the operation schedule. Therefore, if it is determined that there is a high possibility that the created operation schedule and the actual operation result, which is the operating state of the production system, will not be able to comply with the deadline constraint, it is desirable to correct the operation schedule.

Moreover, in the operation of the production system, it is sufficient that the operation plan is input to the MES by the time the operation instructions are transmitted to each piece of equipment.

Therefore, the scheduler only needs to create and output the driving schedule that is required at that time, and there is a possibility that this driving schedule will not be able to meet the delivery date due to a large discrepancy between the driving schedule output in the past and the actual operation results. If it is determined to be high, it is possible to increase the possibility of meeting the constraint by setting an operation schedule with a high possibility of meeting the constraint on the delivery date.

<Configuration of production system>
FIG. 12 is a block diagram showing the configuration of a production system 200 equipped with an operation start condition conversion device 20A according to Embodiment 2 of the present invention. As shown in FIG. 12, the production system 200 includes a scheduler 10A, an operation start condition conversion device 20A, an MES 30, a plurality of manufacturing devices 41, 42 to 4n, a plurality of AGVs 51 to 5m, a schedule division instruction device 60, and an operating state transmission device. It has 70.

Similar to the scheduler 10 of the production system 100 of the first embodiment, the scheduler 10A schedules the operation of the production equipment and the AGV based on order data and operation capability information of the production system input from a data input device (not shown). In addition to creating and outputting, the operating status of each facility such as the manufacturing equipment 41 to 4n and the AGV 51 to 5m detected by the MES 30 is received via the operating status transmitter 70, and the operation information of each facility is also referred to. create a schedule;

As described above, in the operation of the production system, it is sufficient that the operation plan has been input to the MES by the time the operation instructions are sent to each piece of equipment. is not required to be created all at once, and if there is a large discrepancy between the expected operation schedule and the actual operation results, the operation schedule can be divided and created so that the operation schedule can be corrected.

Therefore, the schedule division instruction device 60 instructs the scheduler 10A on how to divide the driving schedule to be created. The division method includes division by time such as 15-minute units. A driving schedule including driving instructions that the MES 30 is supposed to transmit in units of 15 minutes may be output. However, since processing time in the operation start condition conversion device 20A, processing time in the MES 30, and the like also occur, an operation schedule that includes these processing times as extra time is output. For example, if the leeway time is 15 minutes, it is sufficient to output a driving schedule that includes driving instructions that the MES 30 is expected to transmit within 15 to 30 minutes from the current time.

Based on the operation plan input from the operation start condition conversion device 20A, the MES 30 not only transmits operation instructions to each facility such as the manufacturing apparatuses 41 to 4n and AGVs 51 to 5m, but also monitors the operation status of each facility. , and the result is transmitted to the operating state transmitter 70 . The operating state transmitting device 70 receives the operating state of each facility transmitted from the MES 30 and transmits it to the scheduler 10A and the operation start condition converting device 20A.

The scheduler 10A, based on the information on the operating state of each facility transmitted from the operating state transmitting device 70, determines the discrepancy between the operating schedule created in the past and the actual operation results, which is the operating state of the production system based on the operating schedule. It has a deviation detection unit 11 for detection.

Similar to the operation schedule created by the scheduler 10 described above with reference to FIG. 4, the operation schedule created by the scheduler 10A is also a time-specified operation schedule in which the work in each manufacturing apparatus is arranged in chronological order. Therefore, the deviation detection unit 11 creates operation results specified by time based on the information on the operating state of each facility, and compares them with the operation schedule to detect the deviation between the two, for example, the time lag of each work. should be detected. Alternatively, it may be detected whether or not the constraint on the delivery date can be observed. Then, if it is determined that the constraint on the delivery date is unlikely to be met or the constraint cannot be met, the operation schedule to be output next is corrected so that the delivery date can be met.

The scheduler 10A inputs the corrected driving schedule to the driving start condition converter 20A.

FIG. 13 is a functional block diagram showing the configuration of the operation start condition conversion device 20A. In the operation start condition conversion device 20A shown in FIG. 13, the same components as those of the operation start condition conversion device 20 are denoted by the same reference numerals, and overlapping descriptions are omitted.

As shown in FIG. 13, the driving schedule D1, the product data D2 and the work data D3 output from the scheduler 10A (FIG. 12) are input to the driving start condition conversion device 20A via the data input unit 23. It is saved in the storage unit 21 . The storage unit 21 also stores an output operation plan D4 output by the operation start condition conversion device 20A in the past. The output operation plan D4 may be all past operation plans, or may be an operation plan including work related to a certain period of time or an unfinished product.

Information on the operating state of each piece of equipment transmitted from the operating state transmitting device 70 is input to the operating state conversion device 20A via the operating state input unit 225 . The operating state D5 of each facility is input to the product assembly sequence condition setting unit 223 via the operating state input unit 225, and the output operation plan D4 is also input from the storage unit 21. The output operation plan D4 may be input to the product assembly sequence condition setting unit 223 via the operation state input unit 225. FIG.

Then, the product assembly order condition setting unit 223 extracts, for example, the work related to the unfinished product based on the operating state and the output operation plan, and performs the first operation start for the newly input operation schedule. Add conditions.

Similarly, the parts supply condition setting unit 224 extracts, for example, work related to unfinished products and setup change work related thereto based on the operating state and the output operation plan, and adapts it to the newly input operation schedule. In contrast, a second operation start condition is added.

As described above, according to the operation start condition conversion device 20A of the second embodiment, when the operation schedule is divided and created, the operation start condition can be added in consideration of the operation state of each piece of equipment. .

Such a method is effective in order to meet the delivery date when there is a delay in production, for example, in the case of processing high-priority products first, even if there is an increase in setup changes. This is effective when top priority is given to meeting the delivery date even if the number of setup changes increases and the total work time increases.

<Modification>
In the above description, the method of dividing the operation schedule by time has been shown, but it is also possible to divide by product instead of time. For example, regarding the work for one product, the driving schedule is not divided, but is output as a driving schedule including all the work required until the product is completed. With this method, if the manufacturing of the product in question is unlikely to be on time, it is possible to take measures such as creating an operation schedule that prioritizes the manufacturing of the product in question over other low-priority products. can.

Note that division by time and division by product may be combined, or division by time or division by product may be combined with division by another element.

<Acknowledgments>
This research was conducted as part of the Disruptive Research and Development Promotion Program (ImPACT) led by the Council for Science, Technology and Innovation. "This work was funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan)."

In addition, within the scope of the invention, each embodiment can be freely combined, and each embodiment can be appropriately modified or omitted.

20 operation start condition conversion device, 221 work resource classification unit, 222 work type classification unit, 223 product assembly sequence condition setting unit, 224 parts supply condition setting unit.

Claims (6)

a work resource classifying unit that classifies, into work resources with different priorities, a plurality of works included in an operation schedule in which the timing of a plurality of works performed by each piece of equipment of a production system that produces a product is specified by time;
a work type classification unit that classifies the plurality of works into direct work on the product and indirect work on the product including setup change including change of supplied parts or replacement of tools;
a product assembly order condition setting unit that sets, as a first operation start condition, the completion of a low-priority work among the direct work on the product;
a parts supply condition setting unit that sets, as a second operation start condition, the completion of the work affected by the setup change among the indirect works for the product,
The operation schedule is converted into an operation plan specified by an event including the completion of work according to the first and second operation start conditions, and the work for which the operation start condition has been satisfied is executed in order of priority. input to a control system that operates the production system, an operation start condition conversion device. The driving schedule is divided into specific units and input,
The operation start condition conversion device further includes an operation state input unit that receives from the outside the operation state of the production system according to the output operation plan created based on the previously dividedly input operation schedule,
The product assembly order condition setting unit
setting the first operation start condition in the newly divided input operation schedule based on the operation state and the output operation plan;
The component supply condition setting unit
2. The operation start condition conversion device according to claim 1, wherein said second operation start condition is set in said newly divided input operation schedule based on said operation state and said output operation plan. The newly divided input operation schedule is
3. The operation start condition conversion device according to claim 2, wherein the operation schedule is modified so as to reduce a deviation between the previously dividedly input operation schedule and the operation state of the production system based on the operation schedule. The operation plan including the first and second operation start conditions,
2. The operation start condition conversion device according to claim 1, which is input to said control system together with a constraint between said facilities for avoiding interference between said facilities constituting said production system. Constraints between the facilities are:
5. The operation start condition conversion device according to claim 4, which is an interlock including at least a condition that said indirect work on said product cannot be started during execution of said indirect work on said product including said setup change. A step in which the work resource classification unit classifies the plurality of works included in the operation schedule in which the timing of the plurality of works performed by each facility of the production system for producing the product is specified by time into work resources with different priorities. When,
a step in which the work type classification unit classifies the plurality of works into direct work on the product and indirect work on the product including setup change including change of supply parts or replacement of tools;
a step in which a product assembly order condition setting unit sets completion of a low-priority work among the direct works on the product as a first operation start condition;
a part supply condition setting unit setting, as a second operation start condition, the completion of the work affected by the setup change among the indirect works for the product;
The operation start condition conversion device converts the operation schedule into an operation plan specified by an event including the completion of work according to the first and second operation start conditions, and for a control system that operates the production system, A method for converting operation start conditions, in which, among works for which operation start conditions have already been established, operations with higher priority are executed first.

Images