The present disclosure relates to method and apparatus for using design specifications and measurements on manufactured products in conceptual design models.
It is becoming increasingly difficult to execute and manage design and manufacturing processes of complicated products, like automobile vehicles, due to the tightly coupled various activities of various engineering disciplines such as machinery design, electronics design, and software design. Recently a trend has emerged, in which a system-level concept model is defined and used to manage these processes and artifacts in integrated fashion. An example of this concept is shown in OMG: SysML. Using such a concept model, it is possible to solve a number of problems caused as a result of complicated system components being tightly coupled with each other, and it is possible to enlarge communications among different disciplinary engineers. Consequently, high quality products can be released into the market place quickly.
However, there is no way to integrate various existing engineering master databases, such as product design database and bill of materials (BOMs), which are required for product design and manufacturing. There is also a lack of mechanism to collaborate on those components when a system engineer uses such a modeling language and tool, an example of which includes EmbeddedPlus: SysML Toolkit for RSDP. It is inefficient to transform the concept model in the upstream process into the design and manufacturing models in the downstream process. There is no systematic method of validating design changes and manufacturing changes on the concept model, and it is difficult to analyze faults identified in the production and market place by connecting real products to the system model.
In order to address the above problems, L. Balmelli: Generic Graphical Modeling Language Part I proposes that the system engineers who write the concept model access various design and manufacturing information in the BOM through Web services, but there has been no proposal as to how to access non-uniform distributed manufacturing data, which are not always mapped simply to system-level model elements one by one, and how to verify and trace various technical problems such as system-level requirements, satisfied design, and impacted portions due to faults and design changes.
The existing system engineering modeling tool such as a SysML tool, is effective only for development of the initial model and communication among a number of engineers of various disciplinary areas. But, such communication is just one way and there is no method of solving complicated problems related to various designs and manufacturing methods, which occur during detailed design, after finishing manufacturing preparation, and even after starting the production process.
When the system design concept model is created and/or modified, it is generally not easy to refer to or correlate other external data or reference values such as values obtained at manufacturing, production, or after sales stages. For instance, it is difficult to access system design and external values from each other because the system design computing environment is physically and technically different from those of detailed manufacturing design. For example, the system design workstation is located in the office area, but the computers in the production place are special machines that are not connected to each other.
It is also difficult to share design and manufacturing data because the system design organization may be separated from the production organization due to the organizational rules and corporate strategy. For example, as such data are confidential, they are strictly restricted to be accessed from the whole employee by a certain access control. The purchase order of parts in the production place cannot be accessed from system designers.
Furthermore, there is no explicit association between system design model elements and detailed manufacturing design data because the system design is automatically or manually transformed to detailed manufacturing design at many intermediate stages. In the system design phase, functionality may be focused as one model, but in the production place, it is transformed into many structured parts (bill of material), and the relationship between a function and a part is not always one-to-one.
Still yet, it is difficult to manage system level design data and detailed manufacturing data in the integrated way because they have quite different structure and reference method respectively according to each purpose: understanding and abstraction of the target system (system design) vs. various specific design and manufacturing purposes (detailed design and production). For example, model elements in the system-level design are described in order to understand the total product and also to abstract the target system. On the contrary, as detailed manufacturing design information has a different purpose, the information structure and the reference method are different from those of the system-based design. Accordingly, even if the association between the model elements in system-level design and the external reference values in the detailed manufacturing design is clarified, difficult still remains in finding inconsistency among the model, the information structure on the detailed manufacturing design, and the reference method.
A system and method for using design specification and measurements on manufactured products in conceptual design model are provided. The system in one aspect may comprise a conceptual model extender module operable to map one or more model elements to corresponding external reference values. The corresponding external reference values include at least design specification values and manufacturing properties associated with said one or more model elements. The system may also include a presenter module operable to present said one or more model elements mapped to corresponding external reference values and a importer module operable to import said external reference values from one or more external systems for mapping to said one or more model elements.
A method of using design specification and measurements on manufactured products in conceptual design model, in one aspect, may comprise extending a concept model to include mappings of one or more model elements to corresponding reference values, the corresponding external reference values including at least design specification values and manufacturing properties associated with said one or more model elements. The method may also comprise importing said corresponding external reference values from one or more external systems for mapping to said one or more model elements and presenting said mappings of one or more model elements to corresponding reference values to a user.
A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform above described method may also be provided.
Further features as well as the structure and operation of various embodiments are described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements.
The disclose method, system and/or apparatus enable efficient usage of external reference values in the downstream process from system-level concept model. The method and tool are described that relate to how to access the data, how to collaborate on them, and how to verify them in order to efficiently use the external reference values in the detailed-manufacturing process in the downstream process when the system-level concept model is created and modified.
In one aspect, the concept model refers to an abstracted description about the requirements, functions, and behavior of the manufacturing product instance as a total system. Its roles are to coordinate different disciplinary engineering processes of the system and to verify the simulated behavior. More concretely, it is created in the upstream process of the development by a modeling tool, and it is used to generate design and manufacturing directives in the downstream process. The external reference values refer to various engineering property values about technical feature values, quality related statistics, and so on, about the used parts and production method for the targeted manufacturing product. They are stored in the existing manufacturing database systems, for example.
The disclosed method, system and apparatus addresses the difficulties encountered with existing design concept models. For example, the method, system and apparatus of the present disclosure in one embodiment addresses importing data from the downstream process into the modeling tool, building associations between the data and the system model (a method of specifying the associations and representing the structure), presenting and/or or displaying the associations on the diagrams of the modeling tool, and modifying and verifying the system design using such data.
The disclosed method, system and apparatus in one embodiment extends the concept model to provide a tool that can import and map the data from various detailed design and manufacturing data.
A method is also provided for mapping and storing complicated many-to-many associations between the concept model and detailed manufacturing design data. Another procedural method is provided for importing the external data, such as BoM (bill of material) data, and of verifying the consistency. A useful application is also disclosed of the extended system model of the present disclosure with the mappings to various activities in the design and production process.
The tool of the present disclosure creates and modifies the concept model of the system design. For example, the tool imports external reference values, which are useful for improvement and verification of the concept model, for instance, by abstracting and federating heterogeneous data in different computer systems. The tool includes extended data representation to maintain associations between the model elements and BOM parts based on the original model structure (metamodel) in order to associate external reference values in the BOM with elements of the model. The tool may also include a user interface, which enables users to import the BoM structure and data from external databases and to select the corresponding model elements to them in order to specify the associations. Based on the data representation, for example, described above, a method of displaying external reference values and BoM parts on the model diagram other than the concept model elements may be implemented in the program code of the tool. The method enables users to easily create and improve the system design by simultaneously looking at the model elements and the external reference values.
Using the above-described associations, the system, method and apparatus of the present disclosure also presents a program code that traces the requirement associations (“satisfy” association) by extending the existing associations, and a program code that enables to find inconsistency between system design constraints and external reference values. The system, method and apparatus of the present disclosure enables to identify and improve a number of problems caused at the system design, detailed design in the downstream process, and manufacturing design in the further downstream process.
The tool may further implement a program code to identify a pattern of the mappings related to structure of the system design elements and BoM, and a program code that validates associations on the pattern by rues checking the inconsistency. These implemented functions contribute to increase reliability of the tool by validating user's data imported by hand.
Referring to
In one embodiment, such external reference values can be indicated by attaching special text strings, like “<design property>” and “<manufactured property>” (see
According to user's instruction, such new properties from external systems may be highlighted or hidden. As a result of the display, a user can refer to product life cycle data, such as design specification values related to the system concept model at once. A user can detect inconsistency of the data with the system concept model, can improve the product, and even can solve the several problems that may have occurred in the design and manufacturing processes, for instance, perform a root cause analysis about fault parts and quality control.
In general, the system concept model enables to trace requirements to the satisfied elements by defining an association between them. The method, system and/or apparatus of the present disclosure implements an extended requirement tracer 116 that extends the existing “Satisfy” association to trace requirements to external reference values, such as design specification, which satisfies the requirement. For instance, on a user interface such as the one shown in
Extender 118 extends the notation of the conceptual model. The design and manufactured values are represented differently from values not imported from the BoM. For example, the display of the manufacturing properties can be done separately from the other design values of the conceptual design element.
In an embodiment that uses SysML as a conceptual modeling language, the metaclass block 602 represents the conceptual design element, as illustrated in
In an embodiment that uses SysML, the method, system and apparatus of the present disclosure may extend the semantic of the satisfy relationship in the language. The satisfy relationship is used to connect requirement elements to other model elements that satisfy them. An example is shown in
The method, system and apparatus of the present disclosure in one embodiment refine the semantics of the relationship to distinguish between satisfaction by design specifications and satisfaction by manufactured properties. The distinction is useful because these properties emerge at very different stages of the lifecycle. Differentiating between them allows the stakeholders to have a better understanding of the product from a requirement satisfaction standpoint. It is common that a manufacturing product diverges from its specification. Hence even though a product design might fulfill the requirements, its manufactured counterpart might present unexpected issues. The metamodel extensions in one embodiment in SysML are presented in
Referring back to
Importer 120 can perform aggregation, which calculates average, variance, etc. as one of measured values. Importer 120 may include a function to display a histogram for each ranged data. Such analytical data are useful to find and solve various problems that occur during the product lifecycle. For example, importer 120 may have a GUI function to display a list of importable properties and values in order to let a user specify imported properties and values.
To import actual values, a concept model element is specified to be mapped from the imported properties, for instance, shown in
At this time it is possible to restrict the number of displayed properties at once by selecting blocks, objects, or categories, which contain the properties. A user may confirm and transfer the property values to Mapper (
Referring back to
For example, Satisfy association (which specifies a concept model element as a target and a requirement as a source, and which enables the trace of the requirement blocks to satisfied things) can be extended to realize new mappings between the imported properties and the concept model elements. More detailed method of extending the model and of specifying the mappings are described above with reference to CM Extender 118. The extended Satisfy association may be also used in the traceability function.
In one embodiment, the extended mappings among imported properties can be implemented by using the native association mechanism of the modeling tool because the imported properties are handled as the native properties. Such a mapping enables to manage consistency between two related external reference values. It is possible to check if such consistency is kept or not through satisfaction of the constraint expression, which is annotated at the mapping.
In one embodiment, Consistency Manager 122 requires at least two elements in different models to be synchronized using Mapping structure. This manager 122 is used when at least two elements in each model have been synchronized. In one embodiment of the present disclosure invention, CM (conceptual model) is described using SysML and the EM (engineering model) has an instance of a Bill of Material.
A simplified example of the data structure for the bill of material is shown in
To illustrate how contradictions can be reached,
In one embodiment, Change Manager (CM,
Compare 1504: This relationship compares the values between the properties in the two models. For example, a user can use this relationship to compare if the values of the properties are within a certain tolerance, specified in ToleranceModel metaclass 1510. A useful application of this relationship is between values of a specification (in the conceptual model) of the effective values obtained in the manufactured product.
Update 1506: This relationship is used to create dependencies between attributes and how values are dependent on each other. The relationship is used such that whenever the value in any of the properties is changed, the value in the dependent property is changed appropriately or marked as outdated. Update 1506 relationship may in turn depend on whether a change has been approved, for example, specified in DesignChangeApproval metaclass 1512.
Constraint 1508: This relationship is used to create constraints between properties. The nature and the implementation of the constraint 1514 may be left to the user.
The information in the engineering model can be subject to modifications. In one embodiment of the present disclosure, such modification may be propagated to the conceptual model, for example, in the form of change notice. The notice would inform the conceptual designer that a refined specification is available for the conceptual element mapped to the engineering element that has been modified.
The integrated tool described in this disclosure enables to perform root cause analysis, to validate the solution, to identify the impacted portion of the changes, and to manage the change process due to one or more problems. For example, design change of electronics causes impact to mechanical design and/or software design, or, a problem on manufacturing technology causes system-level design changes, etc. The integrated tool described in this disclosure synchronizes such impacts and changes.
The method, system and apparatus of the present disclosure can be useful in many different scenarios of concrete usage, some of which are enumerated below.
Verification of Properties' Tolerance
The comparison between the specified values and the measured values in the manufactured product allows the stakeholders to insure that the manufactured product meets the product requirements. The method, system and apparatus of the present disclosure allow a conceptual model to be used as a repository for both design and manufacturing values and hence for their direct comparison. In one aspect, the conceptual design model offers a unique framework for this usage because it represents the product at the level of its subsystems. Hence a similar approach based on engineering data models used at later stage (e.g., in the Bill of Materials) would not allow for such a discipline-agnostic, systems-oriented representation because BoM has only manufacturing values and does not have specified values in CM. Other discipline specific designs, such as mechanical design, electronics, and embedded software, are the same. Only CM can have various engineering values in a consistent manner.
Requirement Verification against Manufactured Properties' Measurements A conceptual design model allows the inclusion of the product requirements in the model and therefore their traceability to the system components. Using the method, system and/or apparatus of the present disclosure, designer can trace satisfaction throughout the later engineering stages by monitoring the design and manufactured properties. Furthermore, the refinement of the satisfy relationship allows designer to further improve this monitoring process.
A Posteriori Elicitation of Specification based on Manufactured Properties' Measurements
The access to manufactured properties at the conceptual stage creates a feedback loop that offers opportunities to refine the product specification. Using the method, system and/or apparatus of the present disclosure, designers can query the manufactured product for properties not included in the current specification.
Consider the following example. A new safety requirement that requires an engineering design change is added to a manufactured product composed of electrical and mechanical components. The new requirement constrains the operating temperature of the engine hood to remain below a certain value, while satisfying shape specification to keep aerodynamics properties. In this scenario, the designer can instruct the engineers to measure such a value on existing product such that it can be imported in the conceptual design model using the method, system and/or apparatus of the present disclosure. Once the value is available, the designer can use it to produce an updated design specification.
The disclose tool provides a method of detecting inconsistency between constraints in the system-level design and the external reference values in the detailed manufacturing design information by extending the requirement traceability (“satisfy” association) and tracing the associations, based on the requirements described in the model and the derived detailed manufacturing design information. The data structure of the concept model is extended to have mappings from the model elements (system blocks and associated properties) to the corresponding external reference values. The concept model is further extended to represent associations that enable to trace requirements and blocks in the concept model to the satisfied constraints/rules description, which is one of the concept model elements.
An interactive user interface enables building mappings from the system blocks to the corresponding BoM nodes (for instance, assembly parts). Similarly, properties associated to each block are mapped to individual external reference values.
The disclosed tool may also enable deriving constraints and rules based on the mapped concept model elements, and confirming that the constraints are satisfied and the rule is not violated by evaluating the constraint/rule expressions using the external reference values.
The disclosed tool also provides a method of detecting invalidation among the mappings by identifying a pattern about consistency of system-level design elements, BoM structure, and the relationship(s). The concept model is represented as a tree structure in one embodiment, for example, forming a tree by tracing specific associations (functional decomposition, inclusion, and so on) to descendent nodes of the model elements from the top level node mapped from the top level parts in BOM. Searches may be performed to determine whether or not any inversion structure exist in the whole, by investigating the relationship between the tree nodes of the concept model and the tree nodes of BoM.
The system and method of the present disclosure may be implemented and run on a general-purpose computer or computer system. The computer system may be any type of known or will be known systems and may typically include a processor, memory device, a storage device, input/output devices, internal buses, and/or a communications interface for communicating with other computer systems in conjunction with communication hardware and software, etc.
The terms “computer system” and “computer network” as may be used in the present application may include a variety of combinations of fixed and/or portable computer hardware, software, peripherals, and storage devices. The computer system may include a plurality of individual components that are networked or otherwise linked to perform collaboratively, or may include one or more stand-alone components. The hardware and software components of the computer system of the present application may include and may be included within fixed and portable devices such as desktop, laptop, server. A module may be a component of a device, software, program, or system that implements some “functionality”, which can be embodied as software, hardware, firmware, electronic circuitry, or etc.
The embodiments described above are illustrative examples and it should not be construed that the present invention is limited to these particular embodiments. Thus, various changes and modifications may be effected by one skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.