WO2020117221A1

WO2020117221A1 - Improved factory scheduling system and method

Info

Publication number: WO2020117221A1
Application number: PCT/US2018/063987
Authority: WO
Inventors: Lingyun Wang; Kun Ji
Original assignee: Siemens Aktiengesellschaft; Siemens Corporation
Priority date: 2018-12-05
Filing date: 2018-12-05
Publication date: 2020-06-11

Abstract

A system for scheduling operations of a factory includes an online portion that is continuously updated, the online portion having a plurality of machine simulations for each of a plurality of machines within the factory, a plurality of process simulations for each of a plurality of processes within the factory, a plurality of manufacturing plans, each manufacturing plan including the steps to manufacture one of a plurality of items, and a planner coupled to each of the plurality of machine simulations, the plurality of process simulations, and the plurality of manufacturing plans to form a schedule of operations to complete a predefined number of each of a plurality of items. An offline portion periodically updates the online portion and includes a historical data collector operable to collect historical operational data from the plurality of machines and the plurality of processes, and an analytics module operable to analyze the historical operational data and to periodically adjust the plurality of machine simulations and the plurality of process simulations.

Description

IMPROVED FACTORY SCHEDULING SYSTEM AND METHOD

TECHNICAL FIELD

[0001] The present disclosure is directed, in general, to a system and method of scheduling operations within a factory, and more specifically to a system and method that includes continuous and periodic adjustments.

BACKGROUND

[0002] Large factories or manufacturing facilities often include numerous machines or processes that cooperate to manufacture a number of different parts, components, or products. Scheduling the activity factory-wide can be very challenging.

SUMMARY

[0003] A system for scheduling operations of a factory includes an online portion that is continuously updated, the online portion having a plurality of machine simulations for each of a plurality of machines within the factory, a plurality of process simulations for each of a plurality of processes within the factory, a plurality of manufacturing plans, each manufacturing plan including the steps to manufacture one of a plurality of items, and a planner coupled to each of the plurality of machine simulations, the plurality of process simulations, and the plurality of manufacturing plans to form a schedule of operations to complete a predefined number of each of a plurality of items. An offline portion periodically updates the online portion and includes a historical data collector operable to collect historical operational data from the plurality of machines and the plurality of processes, and an analytics module operable to analyze the historical operational data and to periodically adjust the plurality of machine simulations and the plurality of process simulations.

[0004] In another construction, a method of scheduling operations of a factory includes providing a digital simulation of a plurality of machines and processes within the factory, entering a first manufacturing plan for a first item, entering a second manufacturing plan for a second item, selecting a first quantity of first items and a second quantity of second items to be manufactured, and generating a schedule of operations to manufacture the first quantity and the second quantity using a planner coupled to each of the digital simulations, the first

manufacturing plan, and the second manufacturing plan. The method also includes continuously updating the schedule of operations using actual production data provided to the planner by the plurality of machines and processes within the factory, providing the actual production data to a historical data collector to compile historical operating data for each of the plurality of machines and processes within the factory, analyzing the historical operating data to determine if changes to the digital simulations of the plurality of machines and processes within the factory are required, and periodically updating the digital simulations of the plurality of machines and processes within the factory based on the analysis of the historical operating data.

[0005] The foregoing has outlined rather broadly the technical features of the present disclosure so that those skilled in the art may better understand the detailed description that follows.

Additional features and advantages of the disclosure will be described hereinafter that form the subject of the claims. Those skilled in the art will appreciate that they may readily use the conception and the specific embodiments disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Those skilled in the art will also realize that such equivalent constructions do not depart from the spirit and scope of the disclosure in its broadest form.

[0006] Also, before undertaking the Detailed Description below, it should be understood that various definitions for certain words and phrases are provided throughout this specification and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases. While some terms may include a wide variety of embodiments, the appended claims may expressly limit these terms to specific embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a schematic illustration of a scheduling system. [0008] Fig. 2 is a flowchart illustrating a method of maintaining a schedule.

[0009] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

DETAILED DESCRIPTION

[0010] Various technologies that pertain to systems and methods will now be described with reference to the drawings, where like reference numerals represent like elements throughout.

The drawings discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged apparatus. It is to be understood that functionality that is described as being carried out by certain system elements may be performed by multiple elements. Similarly, for instance, an element may be configured to perform functionality that is described as being carried out by multiple elements. The numerous innovative teachings of the present application will be described with reference to exemplary non-limiting embodiments.

[0011] Also, it should be understood that the words or phrases used herein should be construed broadly, unless expressly limited in some examples. For example, the terms“including,” “having,” and“comprising,” as well as derivatives thereof, mean inclusion without limitation.

The singular forms“a”,“an” and“the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, the term“and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. The term“or” is inclusive, meaning and/or, unless the context clearly indicates otherwise. The phrases“associated with” and“associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like.

[0012] Also, although the terms "first", "second", "third" and so forth may be used herein to refer to various elements, information, functions, or acts, these elements, information, functions, or acts should not be limited by these terms. Rather these numeral adjectives are used to distinguish different elements, information, functions or acts from each other. For example, a first element, information, function, or act could be termed a second element, information, function, or act, and, similarly, a second element, information, function, or act could be termed a first element, information, function, or act, without departing from the scope of the present disclosure.

[0013] In addition, the term "adjacent to" may mean: that an element is relatively near to but not in contact with a further element; or that the element is in contact with the further portion, unless the context clearly indicates otherwise. Further, the phrase“based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Terms“about” or“substantially” or like terms are intended to cover variations in a value that are within normal industry manufacturing tolerances for that dimension. If no industry standard as available a variation of 20 percent would fall within the meaning of these terms unless otherwise stated.

[0014] Fig. 1 illustrates the arrangement and operation of a scheduling system 10 that includes aspects that are stored and run within a computer. As is well understood, the software aspects of the present invention could be stored on virtually any computer readable medium including a local disk drive system, a remote server, internet, or cloud-based storage location. In addition, aspects could be stored on portable devices or memory devices as may be required. The computer generally includes an input/output device that allows for access to the software regardless of where it is stored, one or more processors, memory devices, user input devices, and output devices such as monitors, printers, and the like.

[0015] The processor could include a standard micro-processor or could include artificial intelligence accelerators or processors that are specifically designed to perform artificial intelligence applications such as artificial neural networks, machine vision, and machine learning. Typical applications include algorithms for robotics, internet of things, and other data- intensive or sensor-driven tasks. Often AI accelerators are multi-core designs and generally focus on low-precision arithmetic, novel dataflow architectures, or in-memory computing capability. In still other applications, the processor may include a graphics processing unit (GPU) designed for the manipulation of images and the calculation of local image properties.

The mathematical basis of neural networks and image manipulation are similar, leading GPUs to become increasingly used for machine learning tasks. Of course, other processors or arrangements could be employed if desired. Other options include but are not limited to field- programmable gate arrays (FPGA), application-specific integrated circuits (ASIC), and the like.

[0016] The computer also includes communication devices that may allow for communication between other computers or computer networks, as well as for communication with factory devices such as machine tools, work stations and the like.

[0017] Before proceeding, it should be noted that the term“factory” as used herein is meant to be a generic term for many different types of operations. For example, a shop that includes machine tools arranged to simply manufacture parts would be a factory. Similarly, a facility that assembles parts into finished products or services products that have been in use would be considered a factory. Even non-manufacturing-based facilities (e.g., engineering departments, accounting firms, law firms, etc.) could be considered a factory in some applications. Thus, while the following discussion will focus on an example factory that manufactures parts or components, assembles those parts and components into products, and repairs and services products, the term“factory” should not be limited to those types of facilities.

[0018] Returning to Fig. 1, the scheduling system 10 includes an online portion 15 and an offline portion 20. The online portion 15 includes processes and data transfers that happen on a continuous basis. In other words, the data or processes occur as required and do not wait for access to the remainder of the system 10 to transfer data. As used herein“continuous” means that data can be moved, or processes can occur at any time without requiring a connection to another system or any undue delay. The offline portion 20 includes data transfers and processes that may occur on a continuous basis or may occur periodically. In addition, the offline portion 20 updates the online portion 15 periodically as will be discussed further. As used herein, “periodically” means that the process, data transfer, or other activity occurs on a schedule rather than on a continuous basis. Thus, the process, data transfer, or other activity could occur once per hour, once per day, once per week, and the like. In addition, different processes, data transfers, or other activities could occur at different periodic intervals as will be discussed further.

[0019] The online portion 15 of the scheduling system 10 includes the factory 25, a simulation module 30, and a planner module 35. The simulation module 30 include simulations 40 or “digital twins” of each machine 42 and process 44 within the factory 25. The simulations 40 include information that allow for the accurate prediction of durations for certain tasks, thereby making scheduling more accurate. For example, one factory 25 may include three different types of lathes with each lathe having different operating characteristics and capabilities. A particular part may require one hour of time on one of the lathes but three hours on another of the lathes. The simulations 40 provide that information to the planner module 35. Similarly, the simulations 40 may include simulations of processes 44, such as grit blasting, painting, coating application or removal, non-destructive examination, quality control inspections, and the like. While these activities are not necessarily tied to a machine 42, they are predictable in duration and can be simulated.

[0020] The planner module 35 receives inputs such as objectives 45 (e.g., number of parts to make, schedule for completion of different products, etc.), constraints 50 (e.g., deadlines, importance rankings for different tasks, etc.) and work plans 55 (e.g., manufacturing plan for parts, work plan for servicing a product, etc.). The planner module 35 also receives feedback 60 from the factory 25 which may include machine status information, actual completion dates and times for tasks, and the like. The simulations 40 provide information to the planner module 35 such as machine capabilities, process speeds, and the like. The planner module 35 operates in the computer to balance all the inputs and generate a schedule of activities, including a listing of tasks for the factory 25 as well as each machine 42 or process 44 that best meets the objectives 45 and constraints 50 provided to the planner module 35. For example, two different parts may need to use lathes. In the factory 25 with three types of lathes, one of those parts may be particularly suited to manufacture on one type of lathe while the other part may be agnostic. In this case, the planner module 35 would assign the first part to the correct lathe while the second part is assigned to whatever lathes remain open, thereby optimizing the lathe usage. [0021] As noted, the planner module 35 outputs data to the factory 25 to guide the operation of the machines 42 and processes 44 Schedules can be delivered to personnel responsible for many of the processes 44 such that the personnel then control the activities and document the completion times for various tasks. These documented times are then sent to the planner module 35 to update the schedule. The planner module 35 can send schedule data directly to particular machines 42 or to personnel that then coordinate operation of the various machines 42 When a machine 42 completes a task or at other desired intervals, updates can be sent directly from the machine 42 to the planner module 35 to update the schedule.

[0022] The offline portion 20 includes a historian module 65 and an analytics module 70 The historian module 65 communicates with the factory 25 to gather performance and historical data 75 for the various machines 42 and processes 44 For example, each time a lathe completes a part, it stores the duration. Periodically, the lathe sends the duration and part information to the historian module 65 In general, much of the information transferred from the factory 25 to the planner module 35 is also transferred to the historian module 65 As discussed above, the information could transfer continuously from the factory 25 to the historian module 65 or could be transferred periodically (e.g., once per hour, once per day) as desired. The historian module 65 can organize and sort the data for periodic or continuous transfer to the analytics module 70 or the data can simply transfer as it is received.

[0023] The analytics module 70 receives both historical data 80 from the historian module 65 and model data 85 from the simulation module 30 The analytics module 70 analyzes the historical data 80 to determine if the data provided by the simulation module 30 matches the actual factory performance. For example, the simulation module 30 may predict that a certain machine 42 can complete a step on a particular part in one hour. However, the historian module 65 may report that the step is actually taking 1.5 hours. The analytics module 70 collects these inaccuracies and uses them to determine what, if any changes need to be made to the simulations 40 In the proceeding case, the analytics module 70 may determine that the machine 42 in question cannot actually operate at the speed predicted by the simulation 40 of that machine 42 The analytics module 70 would determine that the speed of the machine 42 in the simulation 40 should be reduced. Periodically, the analytics module 70 sends these changes to the simulation module 30 to update the simulations 40 to better match the reality within the factory 25 and to enhance the accuracy of the schedule. In one construction, the analytics module 70 updates the simulation module 30 once per day.

[0024] Fig. 2 includes a flow chart illustrating a portion of the process of operating the scheduling system 10 of Fig. 1. To start, digital simulations of the machines and processes within the factory 25 must be created and provided 90 or made available to the scheduling system 10. The more detailed the simulations 40, the more accurate the scheduling and estimations provided by the system 10. As an input to the planner module 35, certain

manufacturing schedules or plans 55 are provided 95. For example, a particular part may need several operations in a turning center followed by several milling operations. These steps need to be defined and provided to the planner module 35. Similarly, for a service project, the actual work required needs to be defined. For example, a component may need to be grit blasted, followed by a non-destructive examination before the complete work schedule for the component can be determined. All the constraints 50 and objectives 45 must also be provided to the planner module 35 as shown in step 100. The planner module 35 then uses this information to generate a schedule 105 for each machine 42 and process 44 in the factory 25. Production within the factory follows the schedule in step 110 while actual duration or task data is collected 115 and continuously provided to the planner module 35 as shown in step 120 to update the schedule 125. In parallel, the actual duration and task data is provided 130 to the historian module 65, either continuously or periodically. The analytics module 70 reviews the data provided by the historian module 65 in step 135 and periodically updates 140 the simulation module 30 to improve the accuracy of the schedules generated by the planner module 35.

[0025] It should be noted that the factory 25 is not necessarily part of the scheduling system 10. However, it must communicate with the planner module 35 in order to provide real-time or continuous updates, and with the historian module 65 to provide continuous or periodic data related to actual production rates and activities.

[0026] Although an exemplary embodiment of the present disclosure has been described in detail, those skilled in the art will understand that various changes, substitutions, variations, and improvements disclosed herein may be made without departing from the spirit and scope of the disclosure in its broadest form. [0027] None of the description in the present application should be read as implying that any particular element, step, act, or function is an essential element, which must be included in the claim scope: the scope of patented subject matter is defined only by the allowed claims.

Moreover, none of these claims are intended to invoke a means plus function claim construction unless the exact words "means for" are followed by a participle.

Claims

CLAIMS What is claimed is:

1. A system for scheduling operations of a factory, the system comprising:

an online portion that is continuously updated, the online portion including:

a plurality of machine simulations for each of a plurality of machines within the factory;

a plurality of process simulations for each of a plurality of processes within the factory;

a plurality of manufacturing plans, each manufacturing plan including the steps to manufacture one of a plurality of items;

a planner coupled to each of the plurality of machine simulations, the plurality of process simulations, and the plurality of manufacturing plans to form a schedule of operations to complete a predefined number of each of a plurality of items; and an offline portion that periodically updates the online portion, the offline portion including:

a historical data collector operable to collect historical operational data from the plurality of machines and the plurality of processes;

an analytics module operable to analyze the historical operational data and to periodically adjust the plurality of machine simulations and the plurality of process simulations.

2. The system of claim 1, wherein each of the machine simulations includes operating characteristics of the machine.

3. The system of claim 1, wherein each of the process simulations includes a plurality of steps and wherein a time duration for each step is included in the simulation.

4. The system of claim 1, wherein the planner selects the appropriate machine or process for each step of each of the manufacturing plans.

5. The system of claim 4, wherein the planner selects the operating characteristics for a selected machine for a selected step in one of the manufacturing plans and estimates a duration for that step.

6. The system of claim 5, wherein the selected machine sends data to the planner indicative of the actual completion time for the selected step, and wherein the planner updates the schedule of operations in view of the actual completion time.

7. The system of claim 5, wherein the selected machine periodically sends data to the historical data collector, the data including the actual completion time for the selected step.

8. The system of claim 1, wherein each of the plurality of machines and the plurality of processes continuously provides data to the planner related to the completion of steps in the schedule of operations and the planner updates the schedule of operations in view of the data provided.

9. A method of scheduling operations of a factory, the method comprising:

providing a digital simulation of a plurality of machines and processes within the factory; entering a first manufacturing plan for a first item;

entering a second manufacturing plan for a second item;

selecting a first quantity of first items and a second quantity of second items to be manufactured;

generating a schedule of operations to manufacture the first quantity and the second quantity using a planner coupled to each of the digital simulations, the first manufacturing plan, and the second manufacturing plan;

continuously updating the schedule of operations using actual production data provided to the planner by the plurality of machines and processes within the factory;

providing the actual production data to a historical data collector to compile historical operating data for each of the plurality of machines and processes within the factory;

analyzing the historical operating data to determine if changes to the digital simulations of the plurality of machines and processes within the factory are required; and

periodically updating the digital simulations of the plurality of machines and processes within the factory based on the analysis of the historical operating data.

10. The method of claim 9, wherein each of the machine simulations includes operating characteristics of the machine.

11. The method of claim 9, wherein each of the process simulations includes a plurality of steps and wherein a time duration for each step is included in the simulation.

12. The method of claim 9, further comprising selecting with a planner the appropriate machine or process for each step of each of the manufacturing plans.

13. The method of claim 12, further comprising selecting with the planner the the operating characteristics for a selected machine for a selected step in the first manufacturing plan and estimates a duration for that step.

14. The method of claim 13, further comprising sending data from the selected machine to the planner, the data indicative of the actual completion time for the selected step, and updating with the planner the schedule of operations in view of the actual completion time.

15. The method of claim 13, further comprising periodically sending data from the selected machine to the historical data collector, the data including the actual completion time for the selected step.

16. The method of claim 9, further comprising continuously providing data from each of the plurality of machines and processes to the planner, the data related to the completion of steps in the schedule of operations and updating the schedule of operations in view of the data provided.