Method for production planning

Abstract

In a method for production planning by means of a plurality of manufacturing devices (INTMA), tasks (TD) of a work plan (BOP) are compared (MA) with manufacturing capacities (SD) of the manufacturing devices (INTMA) and one or more results (MAQ) of the comparison (MA) are used in the case of the method to respectively commission at least one or more manufacturing devices (INTMA) to match one / more manufacturing capacities (SD) of themselves to the one / more tasks (TD).

Description

Technical Field

[0001] This invention relates to a method for production planning. Background Technology

[0002] In new production design, product models, such as CAD models and parts lists, are regularly determined, and the sequence of manufacturing steps is determined, for example, in the design of work plans.

[0003] In subsequent production planning, specific manufacturing processes are defined based on existing equipment and facility specifications, for example, using a description or mapping structure mBOP. Because production planning is related to available equipment, this method must be repeated for each manufacturing facility.

[0004] Today, manufacturing processes are planned manually for each manufacturing facility. This results in long market entry times for new products and makes manufacturing inflexible due to the high time commitment required. However, these very goals—short market entry times and high flexibility—are relevant to many current market trends, such as contract manufacturing or manufacturing services.

[0005] In the context of Industry 4.0, the "Plug-and-Produce" approach is known, which allows for more flexible production planning. These approaches are based on two fundamental methodologies.

[0006] On the one hand, arrangements are made according to a central plan: the logic of the central plan is based on task or objective descriptions and matches them with the capability descriptions of the entire set of equipment and machines at the manufacturing level. However, the capabilities of machines often cannot be fully described as descriptive. This is especially true for more complex machines.

[0007] On the other hand, there is a decentralized approach: such an approach requires the use of only intelligent machines, which must themselves have planning capabilities.

[0008] However, the need for coordination functions remains, which often lead to suboptimal solutions and incur additional communication overhead. Summary of the Invention

[0009] Therefore, the objective of this invention is to develop a method that allows for improved production planning, particularly flexible production planning, and that is suitably capable of handling capacity descriptions of varying granularity and machines of varying complexity. This objective is achieved by utilizing a method for production planning performed using multiple manufacturing apparatuses and by employing a computer program product for production planning.

[0010] The method according to the invention is a production planning method using multiple manufacturing devices. In the method according to the invention, the tasks of work planning are compared with the manufacturing capabilities of the manufacturing devices, and based on one or more results of the comparison, at least one or more manufacturing devices are respectively assigned to match their own manufacturing capabilities with the one or more tasks. Preferably, in the method according to the invention, the production plan is recorded based on the results of the comparison and matching. Advantageously, the method is implemented by a computer, supported by a computer, or based on a computer.

[0011] According to the present invention, it is therefore possible to associate central production planning based on capacity description with decentralized production planning at the level of individual manufacturing units within a manufacturing facility, depending on the circumstances. This hierarchical approach avoids the drawbacks of associating production planning with either a central or decentralized system.

[0012] This invention thus allows for situational production planning within a Manufacturing Execution System (MES). This production planning is related to one or more results of a comparison between the description of the tasks in the work plan (i.e., in a product-centric manner) and the description of manufacturing capabilities (i.e., in a facility-centric manner), as well as to the corresponding planning algorithm. Preferably, in the case of the method according to the invention, the comparison is not made, or at least not merely syntactically, but rather, particularly semantically, i.e., by means of a semantic comparison between the corresponding descriptions of one or more tasks and the corresponding descriptions of one or more manufacturing capabilities. The main idea of ​​the invention is to determine, situationally, whether centralized planning based on task descriptions is sufficient or whether decentralized production planning is necessary at the manufacturing unit, such as the machine level. With the method according to the invention, a core problem in flexible production planning situations can be solved: bridging the gap between highly abstract task descriptions at the level of the production management system and capability descriptions at the machine level, where the machine-level capability descriptions often cannot be described at the required granularity because, for example, parameters are unavailable.

[0013] Preferably, if none of these manufacturing devices possesses at least one assignable manufacturing capability for at least one task of the work plan, that is, in particular, if no description of the manufacturing capability of any manufacturing device can be assigned to the description of at least one task of the work plan, then in the case of the method according to the invention, it is preferable to entrust one or more manufacturing devices for matching. This situation may occur, for example, when the manufacturing description of the manufacturing device is not present in a sufficiently granular or comprehensive manner, or when the capability description cannot be fully described without depending on the specific product to be manufactured or the specific manufacturing process required.

[0014] In advantageous extensions of the method according to the invention, comparisons and / or matching are performed semantically and / or by means of logical expressions, especially by means of first-order predicate logic and / or descriptive logic and / or multi-attribute comparisons and / or by means of constraint-based comparisons, especially by means of solving the constraint-satisfaction problem (CSP).

[0015] Semantic comparison is suitably performed, particularly with the aid of "Complex Semantic Matching" (preferably refer to S. Grimm, B. Motik, C. Preist: "Matching Semantic Service Descriptions with Local Closed-World Reasoning", ESWC 2006, pp. 575-589; and / or Noia, Tommaso Di et al.: "A System for principalized matchmaking in an electronic marketplace", International Journal of Electronic Commerce 8.4 (2004), pp. 9-37). Preferably, in the case of the method according to the invention, for such semantic comparison, capability descriptions and / or task descriptions and / or context descriptions are employed, wherein the capability descriptions and / or task descriptions and / or context descriptions include logical expressions, especially descriptive logic and / or predicate logic, which are preferably at least first-order.

[0016] Alternatively or additionally, semantic comparison can be performed using multi-attributive matching (especially refer to Veit, Daniel: "Matchmaking in electronic markets: An agent-based approach towards matchmaking in electronic negotiations", Vol. 2882, Springer Science & Business Media, 2003), where one or more task descriptions and / or one or more capability descriptions and / or at least one or more preferred context descriptions include a list of attributes, and where a comparison function is suitably set for one, more, or each type of attribute, the comparison function including, in particular, a semantic comparison function and / or string manipulation and / or mathematical equations.

[0017] Preferably, for matching according to the method of the invention, a description of one or more tasks and preferably at least one possible context description are transmitted to the corresponding manufacturing device. During matching, at least one local matching function, i.e., particularly one related to the corresponding manufacturing device, is suitably evaluated, the matching function being capable of adopting logical values, preferably in a manner representing "true" and / or "false" and / or "unknown". Preferably, at least one internal simulation and / or at least one motion planning and / or at least one other planning algorithm is employed for matching. Advantageously, whenever the corresponding manufacturing device can supplement the missing capability description, that supplement is output as a result of the method.

[0018] In the case of the method according to the invention, manual matching is suitably performed in cases of at least one non-definite match with at least one manufacturing capability. In an extension of the invention, it is therefore not necessary to arrange the matching solely based on automated matching, but rather, in this extension, individual control over the automated method is maintained.

[0019] In the method according to the invention, if the comparison concludes that the manufacturing capacity of the manufacturing apparatus can be allocated to all tasks of the work plan in the allocation, then preferably the result of the comparison and / or the allocation is recorded as a result of the method.

[0020] In an advantageous extension of the method according to the invention, the work plan for the product is refined if more manufacturing capacity is available than the manufacturing capacity required by the work plan. In this extension of the invention, the allocation of manufacturing capacity to the work plan can thus be optimized by adapting the manufacturing capacity to the refined work plan.

[0021] The comparison can be suitably performed using a production management system in accordance with the method of the present invention.

[0022] In the case of the method according to the invention, the matching result is preferably transmitted to the production management system.

[0023] The computer program product according to the present invention, used for production planning, is constructed to implement the method as described above.

[0024] In contrast, known solutions to date are based either on centralized or decentralized production planning, but not on a combination of these two approaches depending on the circumstances, such as in terms of the level of detail described based on the capabilities of the manufacturing equipment. Attached Figure Description

[0025] The invention will now be further described with reference to embodiments shown in the accompanying drawings. Wherein: Figure 1 A flowchart illustrating a first embodiment of the method according to the present invention is shown in the schematic diagram; and Figure 2 The system architecture is schematically illustrated in a principle sketch, and the system architecture includes, according to... Figure 1 Examples of implementations. Detailed Implementation

[0026] According to the method of the present invention Figure 1 The illustrated embodiment shows a flowchart of a Production Management System (MES) for a manufacturing facility, which is not exhaustive in the figure. The manufacturing facility includes multiple manufacturing units. Each manufacturing unit has the capability to manufacture products. The manufacturing capabilities of these units are recorded in a capability description (SD). The MES includes a work plan comprising task descriptions (TDs) that the manufacturing facility must execute to manufacture a given product. Additionally, the work plan also includes context descriptions (Cs) for these task descriptions (TDs). These context descriptions (Cs) include the technical context of the corresponding task, such as its temporal relationship to previous or subsequent tasks in the work plan. In other embodiments, not specifically shown but otherwise corresponding to the illustrated embodiment, these context descriptions (Cs) may be omitted without substitution.

[0027] In order to plan the manufacturing process, the Production Management System (MES) must compare the Task Description (TD) and Capacity Description (SD).

[0028] This comparison of MA can, in principle, be performed in different ways: In the illustrated embodiment, the comparison of MAs is carried out with the aid of "Complex Semantic Matching" (e.g., see S. Grimm, B. Motik, C. Preist: "Matching Semantic Service Descriptions with Local Closed-World Reasoning", ESWC 2006, pp. 575-589; and Noia, Tommaso Di et al.: "A System for principled matchmaking in an electronic marketplace", International Journal of Electronic Commerce 8.4 (2004), pp. 9-37), in which there are capability descriptions, task descriptions and context descriptions carried out with the aid of logical expressions, such as first-order predicate logic or descriptive logic.

[0029] In other embodiments, the comparison of MAs may be alternatively or additionally performed using multi-attributive matching (e.g., see Veit, Daniel: "Matchmaking in electronic markets: An agent-based approach towards matchmaking in electronic negotiation", Vol. 2882, Springer Science & Business Media, 2003), where the task descriptions, capability descriptions, and context descriptions are lists of attributes, and a comparison function is defined for each type of attribute, which may be designed, for example, as a semantic comparison function and / or string manipulation and / or mathematical equation.

[0030] The capability description of the robotic arm constitutes an example of a type of pseudocode for a multi-attribute capability description SD, where the robotic arm constitutes a manufacturing apparatus: {Skill: "Pick & Place";} Degrees of freedom: 6 (number) Effective load: 0 to 3 kg.

[0031] In addition, the multi-attribute description can also include other information about the robotic arm, such as serial number, manufacturer, type name, etc.

[0032] The task description TD, as illustrated here as pseudocode, is as follows: Piece length: 200 mm Part weight: 0.5 kg Task: Transportation.

[0033] Multi-attribute comparison (MA) assigns a semantic representation to each relevant pair of attributes. Semantic comparison is performed on each pair of tasks and manufacturing capabilities. Background knowledge is considered, which formally records the relationships between representations. For example, for a processing function, the following knowledge base is considered, which defines two functions and the relationships between them: Knowledge base = {Transportation, Pickup and Release, Pickup and Release} transportation}.

[0034] Based on the knowledge provided by this foundation, it can be inferred that the functions of "taking and putting" are specific manifestations of the more generalized function of "transportation." In this way, the consistency between tasks and manufacturing capabilities can be determined.

[0035] Instead of one or all of the previously mentioned types of comparison MAs, or in addition to one or both of the previously mentioned types of comparison MAs, comparison MAs can also be performed using constraint-based matching, where the comparison is performed by solving a constraint-satisfaction problem (CSP).

[0036] This comparison MA can be derived from different results MAQ: If for all task descriptions TD of the work plan there is a suitable capability description SD for the manufacturing equipment of the manufacturing facility, then the result MAQ of the comparison MA is "true".

[0037] If the task description TD and the manufacturing facility's manufacturing equipment capability description SD are matched, the result MAQ of the comparison MA will therefore be "false".

[0038] If for each task description TD there exists a suitable capability description SD, but there are additional capability description SDs that are not assigned to task description TDs beyond the number of task description TDs, the result MAQ of the comparison MA is "overdetermined (überbestimmt)"ovd.

[0039] If, although there exists a suitable task description TD for each capability description SD, there are additional task description TDs that have not been assigned to a capability description SD beyond the number of capability description SDs, then the result MAQ of the comparison MA is correspondingly "undetermined".

[0040] If the result MAQ of the comparison MA is "true" or "false", then the result MAQ of the comparison MA is output as the result RES using the output tof.

[0041] If the result MAQ of the comparison MA is "overdetermined" (ovd), an incompletely consistent IM is determined. In this case, either the work plan needs to be refined by updating the UAL to obtain a result MAQ as "true" or "false" based on the adapted task description TD, or it needs to be stipulated that the assigned capability description SD is always compatible with the corresponding task description TD, so that in the case of an incompletely consistent IM, the result MAQ "true" or "false" can always be derived from the existing incompletely consistent IM. In this case, the result MAQ is also communicated to the production planning engineer as the result RES via the output tof, as described above.

[0042] If the result MAQ of the comparison MA is "underdetermined", that is, if there is a task description TD that cannot be assigned a capability description SD based on the current data, then the capability description SD of the manufacturing device may not be known in a sufficiently granular manner or specified sufficiently comprehensively so that the result MAQ of the comparison MA can ultimately be determined as "true" or "false".

[0043] Therefore, these manufacturing facilities are commissioned to perform NEG matching in order to match their own applicability to the task description TD with that task description TD. This is typically especially true for complex and flexible manufacturing facilities, such as robots or machine tools, in which the capability description cannot be fully described without depending on the specific product to be manufactured or the specific manufacturing process required.

[0044] To match NEG, the task description TD and any possible context description C are transmitted to the corresponding manufacturing device. For matching, a local matching function LM associated with the corresponding manufacturing device is evaluated, which can accept the value "true," "false," or "unknown" unk. The matching function LM may employ, for example, internal simulation, motion planning, or other planning algorithms. Whenever the manufacturing device supplements the missing capability description and thus can determine whether the result of the matching function LM is "true" or "false," the result is output as the result RES of the method using the output tof. However, if the matching function LM ultimately yields an "unknown" unk despite the matching, a manual resolution MAR is initiated.

[0045] Given the imperfect consistency of the IM aspect, it can be assumed by standard that the Task Description (TD) is comprehensive and ignores any additional Capability Descriptions (SDs) that cannot be agreed upon with the Task Description TD. Therefore, the result MAQ "True" can be directly obtained and communicated to the Production Planning Engineer via the output "yes". To transparently record the ignored capability attributes, these are entered into a prerequisite list, which is regularly updated with the Update UAL. This prerequisite list can be used later to refine product specifications and work planning.

[0046] exist Figure 2 The global system architecture is shown below: The Production Management System (MES) obtains Task Descriptions (TDs) from the Work Plan (BOP) and the Parts List (BOM). The Work Plan (BOP) and the Parts List (BOM) are derived in part from the Production Plan (PPD) / Product Specification (PPD).

[0047] At the Manufacturing Execution System (MES) level, the Comparison Unit (PPM) is used to compare the Task Description (TD) with the Capacity Description (SD). In the case of incomplete consistency (IM), the match between the Capacity Description (SD) and the Task Description (TD) is transmitted to each Manufacturing Unit (INTMA), which performs the match using its matching unit (PP). The Manufacturing Unit (INTMA) then sends the match result, performed using the Matching Function (LM), back to the MES.

[0048] The production management system (MES) adapts the production planning / product specification (PPD) to the comparison results (MAQ) performed by the comparison unit (PPM) when necessary.

Claims

1. A method for production planning using multiple manufacturing units (INTMAs), wherein, in the case of the method, a task (TD) of a work plan (BOP) is compared (MA) with the manufacturing capacity (SD) of the manufacturing units (INTMAs), and in the case of the method, at least one or more manufacturing units (INTMAs) are respectively assigned, based on one or more results (MAQ) of the comparison (MA), to match one or more of their own manufacturing capacities (SD) with one or more tasks (TDs), wherein if, for at least one task (TD) of the work plan, none of the manufacturing units (INTMAs) has at least one task that can be assigned to the work plan. The manufacturing capability (SD) of a task is then assigned to one or more manufacturing facilities (INTMA) for matching (NEG). Matching (NEG) in cases where none of the manufacturing facilities (INTMA) for at least one task (TD) in the work plan has at least one manufacturing capability (SD) includes matching using internal simulation, motion planning, or other planning algorithms, such that the one or more manufacturing facilities (INTMA) can supplement the missing capability description. The comparison (MA) is performed using a production management system (MES) and is performed semantically. The result of the matching (NEG) is transmitted to the production management system (MES).

2. The method according to claim 1, wherein, The comparison is made by semantic comparison of the description of one or more tasks with one of the descriptions of one or more manufacturing capabilities.

3. The method according to claim 1 or 2, wherein, The comparisons and / or the matching (NEG) are performed using logical expressions and / or constraint-based comparisons.

4. The method according to claim 3, wherein, The comparisons and / or the matching (NEG) are performed using first-order predicate logic and / or descriptive logic and / or multi-attribute comparisons.

5. The method according to claim 3, wherein, The comparison and / or the matching (NEG) are performed by solving a condition satisfaction problem.

6. The method according to claim 2, wherein, In the case of the match, the description of the one or more tasks and / or the possible context description is transmitted to the corresponding manufacturing device, and / or at least one internal simulation and / or at least one motion planning and / or at least one planning algorithm is employed.

7. The method according to claim 1 or 2, wherein, Manual matching is performed in cases of at least one non-positive match (NEG) with at least one manufacturing capability (SD).

8. The method according to claim 1 or 2, wherein, If the comparison (MA) concludes that the manufacturing capacity (SD) of the manufacturing apparatus (INTMA) can be allocated to all tasks (TD) of the work plan (BOP) in the allocation, then the result (MAQ) of the comparison (MA) and / or the allocation is recorded as a result of the method.

9. The method according to claim 1 or 2, wherein, If there is more manufacturing capacity (SD) available compared to the manufacturing capacity required by the said work plan (BOP), then the product's work plan (BOP) is refined.

10. A computer program product for production planning, said computer program product being configured to implement the method according to any one of claims 1 to 9.

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