CN114997132A

CN114997132A - Complex product design system

Info

Publication number: CN114997132A
Application number: CN202210652986.5A
Authority: CN
Inventors: 王儒; 黄禹; 王国新; 魏竹琴
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2022-06-09
Filing date: 2022-06-09
Publication date: 2022-09-02

Abstract

The invention discloses a complex product design system, which relates to the technical field of complex product design, wherein a decision process template retrieval module is used for retrieving a decision template according to an input design problem; the decision process template modification module is used for modifying the retrieved decision template according to the design index when the retrieved decision template is reusable, so as to obtain a modified decision template; the decision process instance creating module is used for recreating a decision template matched with the design problem in the decision process template module when the retrieved decision template cannot be reused; the decision process template modification module is also used for carrying out consistency check on the decision template matched with the design problem or the modified decision template to obtain a decision template in accordance with the consistency; the decision process instance creating module is also used for solving the decision template which accords with the consistency by utilizing the knowledge tool module to generate a design scheme of the design object. The invention can describe the process behavior of the designer in the design decision process.

Description

Complex product design system

Technical Field

The invention relates to the technical field of complex product design, in particular to a complex product design system.

Background

The complex product is a complex integrating multiple discipline knowledge, and is characterized in that: multiple systems, namely, a plurality of subsystems can be decomposed during product design; multi-scale, i.e., the size of a complex product, up to an aircraft carrier, down to an engine, etc.; multi-domain, i.e., product knowledge involved in designing complex products, is multi-domain. In engineering background, products involving multiple fields and multiple subjects, namely complex products such as heat exchangers, need to be designed by considering two parts of thermodynamic design and mechanical design, and the overall design also needs to consider cost and construction design.

In the design process of a complex product, designers often make the complex product meet new design requirements by modifying an existing design scheme so as to shorten the design time and ensure the design quality. In the innovative design of most complex products, the prior design has more references, a large number of design rules need to be followed in the design, and the decision is made by depending on the experience of designers, so that the design process needs to consume a large amount of time, the design efficiency is low, and meanwhile, the domain knowledge is lack of scientific and effective inheritance. Therefore, the traditional design mode and method for complex products cannot meet the requirement of modern product development, and an automatic and intelligent complex product design method is particularly needed to replace the traditional design mode and method.

Currently, for modeling a design model and a design process of a complex product, some focus is on analysis and synthesis of certain specific problems, and some focus is on planning of a business process design activity in design. However, few studies have considered the design of decision processes, i.e., the partitioning of design problems and the planning of decision activities, which describe the process behavior of designers in a decision workflow. Therefore, it is necessary to construct a complex product design system capable of describing the process behavior of the designer in the design decision process according to the "meta-design" requirements and characteristics of the decision workflow in the complex product design.

Disclosure of Invention

The invention aims to provide a complex product design system for describing process behaviors of designers in a design decision process.

In order to achieve the purpose, the invention provides the following scheme:

a complex product design system comprises a design problem input module, a decision process template retrieval module, a judgment module, a decision process template modification module, a decision process instance creation module, a decision process template module and a knowledge tool module;

the design problem input module is used for acquiring a design problem input by a user; the design problem comprises a design object, a plurality of design indexes, the weight of each design index and the threshold value of each design index;

the decision process template retrieval module is used for retrieving a decision template according to the design problem; the decision template comprises a design process template, a stage process template, an event process template, a decision process template and a task process template;

the judging module is used for judging whether the retrieved decision-making template can be reused;

the decision process template modification module is used for modifying the retrieved decision template according to the design index when the output result of the judgment module is yes, so that the retrieved decision template is matched and applied to the design problem to obtain a modified decision template;

the decision process instance creating module is used for recreating a decision template matched with the design problem in the decision process template module when the output result of the judging module is negative, acquiring the decision template matched with the design problem from the decision process template module, and storing the decision template matched with the design problem;

the decision process template modification module is also used for carrying out consistency check on the decision template matched with the design problem or the modified decision template to obtain a decision template in accordance with consistency;

the decision process instance creating module is further configured to obtain the decision template meeting consistency from the decision process template modifying module, and solve the decision template meeting consistency by using the knowledge tool module to generate a design scheme of the design object.

Optionally, the decision process template retrieval module specifically includes a semantic retrieval unit, an ontology library and a feature retrieval unit;

the ontology library is used for accessing the decision template;

the semantic retrieval unit is used for retrieving the decision template from the ontology base based on semantic similarity according to the design problem;

the characteristic retrieval unit is used for retrieving the decision template from the ontology library based on the characteristics of the design object according to the design problem.

Optionally, the decision process template modification module specifically includes a decision process template modification unit, a decision process template consistency check unit and a rule base;

the decision process template modifying unit is used for modifying the retrieved decision template according to the design index when the output result of the judging module is yes, so that the retrieved decision template is matched and applied to the design problem to obtain a modified decision template;

the decision process template consistency checking unit is used for carrying out consistency checking on the decision template matched with the design problem or the modified decision template to obtain a decision template in accordance with consistency;

the rule base is used for accessing the decision template modification rule; and the decision process template consistency checking unit checks whether the decision template is matched with the design problem according to the decision template modification rule.

Optionally, the decision process instance creating module specifically includes a process modeling panel unit, a process modeling tool unit, a process modeling element unit, an executable knowledge component unit, a decision solving unit, a visualization unit, a decision process management unit, and a decision process instance library;

the process modeling panel unit is used for creating a panel of a decision template;

the process modeling tool unit is used for recreating a decision-making template matched with the design problem in the decision-making process template module when the output result of the judging module is negative;

the process modeling element unit is used for providing elements required for creating a decision template;

the executable knowledge component unit is used for acquiring the knowledge of the decision template from the decision process knowledge module and storing the knowledge of the decision template;

the decision solving unit is used for acquiring the decision template which accords with the consistency from the decision process template modification module, and solving the decision template which accords with the consistency by using the knowledge tool module to generate a design scheme of the design object;

the visualization unit is used for performing visualization expression on the design scheme by using the knowledge tool module to obtain a visualization result;

the decision process management unit is used for adding, deleting, editing and inquiring a decision template;

and the decision process example base is used for acquiring the decision template matched with the design problem from the decision process template module and then storing the decision template matched with the design problem.

Optionally, the system further comprises a decision process element module;

the decision process element module is used for storing elements required for creating a decision template and providing the elements required for creating the decision template for the process modeling element unit.

Optionally, the system further comprises a design scheme judging module, a design scheme outputting module and a returning module;

the design scheme judging module is used for judging whether the design scheme achieves a satisfactory result or not according to the visual result;

the design scheme output module is used for outputting the design scheme when the output result of the design scheme judging module is yes;

and the returning module is used for returning to the decision process template modifying module to modify the decision template again when the output result of the design scheme judging module is negative.

Optionally, the decision process template module specifically includes a design process template library, a stage process template library, an event process template library, a decision process template library and a task process template library;

the design process template library is used for storing design process templates; the stage process template library is used for storing stage process templates; the event process template library is used for storing event process templates; the decision process template library is used for storing decision process templates; the task process template library is used for storing task process templates.

Optionally, the knowledge tool module specifically includes a decision model solver, a specialized software tool library and a visualization tool library;

the decision model solver is used for solving the decision template which accords with the consistency to generate a design scheme of the design object;

the professional software tool library and the visual tool library are used for carrying out visual expression on the design scheme to obtain a visual result.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

the invention discloses a complex product design system.A decision process template retrieval module is arranged to retrieve decision modules (comprising a design process template, a stage process template, an event process template, a decision process template and a task process template) according to design problems, when the retrieved decision templates can be reused, the retrieved decision templates are properly modified to be matched and applied to the design problems, when the retrieved decision templates can not be reused, the decision templates matched with the design problems are re-created, solution is carried out based on the decision templates to generate a design scheme of a design object, and the design process template, the stage process template, the event process template, the decision process template and the task process template matched with the design problems are used to describe the process behaviors of designers in the design decision process, thereby realizing the acquisition of reusable information and knowledge in the design of decision workflow, the acquisition of reusable information and knowledge in the design of the decision workflow, the implementation of the design of the complex product, the design of the design, And the representation and the storage increase the efficiency and the effectiveness of the decision workflow design.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a block diagram of a complex product design system embodiment of the present invention;

FIG. 2 is a schematic diagram of a basic architecture of a complex product design decision process modeling system according to the present invention;

FIG. 3 is a schematic diagram of a workflow of a complex product design decision process modeling method of the present invention;

FIG. 4 is a schematic diagram of information interaction between a process model and a product model according to the present invention;

FIG. 5 is a schematic diagram of a full cycle process modeling of the system design of the present invention;

FIG. 6 is a schematic diagram of the relationship of five templates according to the present invention;

FIG. 7 is a diagram illustrating the relationship between events and tasks/decisions according to the present invention;

fig. 8 is a schematic view of a shell and tube heat exchanger according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Fig. 1 is a block diagram of an embodiment of a complex product design system according to the present invention. Referring to FIG. 1, the complex product design system includes a design issue input module 101, a decision process template retrieval module 110, a decision module 102, a decision process template modification module 120, a decision process instance creation module 130, a decision process template module 210, and a knowledge tool module 320.

The design problem input module 101 is used for acquiring a design problem input by a user; the design problem includes a design object, a plurality of design indices, a weight of each design index, and a threshold value of each design index.

The decision process template retrieval module 110 is used for retrieving a decision template according to a design problem; the decision templates include a design process template, a stage process template, an event process template, a decision process template, and a task process template.

The determining module 102 is configured to determine whether the retrieved decision template can be reused.

The decision process template modifying module 120 is configured to modify the retrieved decision template according to the design index when the output result of the determining module 102 is yes, so that the retrieved decision template is matched and applied to the design problem to obtain a modified decision template.

The decision process instance creating module 130 is configured to, when the output result of the determining module 102 is negative, re-create a decision template matching the design problem in the decision process template module 210, obtain a decision template matching the design problem from the decision process template module 210, and store the decision template matching the design problem.

The decision process template modification module 120 is further configured to perform consistency check on the decision template matched with the design problem or the modified decision template, so as to obtain a decision template meeting the consistency.

The decision-making process instance creating module 130 is further configured to obtain the consistent decision-making template from the decision-making process template modifying module 120, and solve the consistent decision-making template by using the knowledge tool module 320 to generate a design solution of the design object.

FIG. 2 is a schematic diagram of the basic architecture of the complex product design decision process modeling system, which explains the composition and functions of the system from the architecture level. FIG. 2 shows a human-computer interaction interface of the complex product design decision process modeling system (complex product design system) of the present invention. Referring to fig. 2, the decision process template retrieving module 110 specifically includes a semantic retrieving unit 111, an ontology library 112, and a feature retrieving unit 113.

The ontology library 112 is used to access decision templates.

The semantic retrieval unit 111 is used for retrieving the decision template from the ontology base based on semantic similarity according to the design problem.

The feature retrieving unit 113 is configured to retrieve a decision template from the ontology library based on features of the design object according to the design problem.

The decision process template modification module 120 specifically includes a decision process template modification unit 121, a decision process template consistency checking unit 122, and a rule base 123.

The decision process template modifying unit 121 is configured to modify the retrieved decision template according to the design index when the output result of the determining module 102 is yes, so that the retrieved decision template is matched and applied to the design problem, and a modified decision template is obtained.

The decision process template consistency checking unit 122 is configured to perform consistency checking on the decision template matched with the design problem or the modified decision template to obtain a decision template meeting consistency.

The rule base 123 is used for accessing decision template modification rules; the decision process template consistency checking unit 122 checks whether the decision template is matched with the design problem according to the decision template modification rule to realize consistency checking, so as to obtain a decision template which accords with consistency.

The decision process instance creation module 130 specifically includes a process modeling panel unit 131, a process modeling tool unit 132, a process modeling element unit 133, an executable knowledge component unit 136, a decision solving unit 137, a visualization unit 138, a decision process management unit 135, and a decision process instance library 134.

The process modeling panel unit 131 is used to create a panel of decision templates.

The process modeling tool unit 132 is used to recreate the decision template matching the design issue in the decision process template module 210 when the output of the decision module 102 is negative.

The process modeling element unit 133 is used to provide elements required to create a decision template.

The executable knowledge component unit 136 is operable to obtain knowledge of the decision template from the decision process knowledge module 310 and store the knowledge of the decision template.

The decision solving unit 137 is configured to obtain the consistent decision template from the decision process template modifying module 120, and solve the consistent decision template by using the knowledge tool module 320, so as to generate a design solution of the design object.

The visualization unit 138 is configured to perform visualization expression on the design scheme by using the knowledge tool module 320 to obtain a visualization result;

the decision process management unit 135 is used to add, delete, edit and query decision templates.

The decision process instance base 134 is used for obtaining the decision template matching the design problem from the decision process template module 210, and then storing the decision template matching the design problem.

The complex product design system also includes a decision process element module 220. The decision process element module 220 is used to store elements required for creating a decision template and provide the elements required for creating a decision template to the process modeling element unit 133.

The complex product design system also comprises a design scheme judging module, a design scheme outputting module and a returning module.

And the design scheme judging module is used for judging whether the design scheme achieves a satisfactory result or not according to the visual result.

And the design scheme output module is used for outputting the design scheme when the output result of the design scheme judging module is yes.

The returning module is configured to return to the decision process template modifying module 120 to modify the decision template again when the output result of the design solution determining module is negative.

The decision process template module 210 specifically includes a design process template library 212, a phase process template library 213, an event process template library 214, a decision process template library 215, and a task process template library 216.

The design process template library 212 is used for storing design process templates; the stage process template library 213 is used for storing stage process templates; the event process template library 214 is used for storing event process templates; the decision process template library 215 is used for storing decision process templates; the task process template library 216 is used to store task process templates.

The knowledge tool module 320 specifically includes a decision model solver 322, a specialized software tool library 323, and a visualization tool library 324.

The decision model solver 322 is used for solving the consistent decision template to generate a design scheme of the design object.

The professional software tool library 323 and the visualization tool library 324 are used for performing visualization expression on the design scheme to obtain a visualization result.

As can be seen from fig. 2, the present invention provides a complex product design decision process modeling system (complex product design system) comprising a decision process modeling management subsystem 100, a decision process knowledge management subsystem (decision knowledge management subsystem) 200, and a general knowledge management subsystem 300.

The decision process modeling management subsystem 100 is used to implement three functions of satisfying the retrieval of the first decision process template, the modification of the first decision process template, and the creation of a decision process (first decision process template) instance. According to the implementation of these three functions, the decision process modeling management subsystem 100 includes a decision process module retrieval module (decision process template retrieval module) 110 for retrieving (via similarity calculation) available decision modules, a decision process module modification module (decision process template modification module) 120 for modifying existing decision modules, and a decision process instance creation module 130 for creating new decision modules. Wherein the decision module is a decision template, and the decision template is a first decision process template (decision process module).

The retrieval mode of the decision process template retrieval module 110 is divided into semantic retrieval and feature retrieval. Before the example matching retrieval is carried out, a designer needs to set the number of the obtained similar examples and a similarity threshold value. After the technical indexes and the weights corresponding to the indexes are obtained, an example library is indexed, the similarity of each example is calculated and obtained, and finally, an example with the similarity larger than a set threshold value is selected to form a similar actual set. Interaction with a design example library is required in the example retrieval process, the design example library provides reference for the existing design problem and absorbs mature design schemes at the same time, and new design knowledge is continuously accumulated.

The decision process template retrieval module 110 comprises a semantic retrieval unit 111 for packaging semantic retrieval similarity, an ontology library 112 for accessing a first decision process template, and a feature retrieval unit 113 for packaging an example similarity calculation engine; the search mechanism of the decision process template search module 110 is of two types: and searching from the ontology library based on the semantic similarity and searching based on the characteristics of the complex product.

The decision process template modification module 120 is modified as follows:

the auxiliary modification is divided into 3 levels: (1) and shallow layer assistance, namely in the parameter modification process, based on the semantic modeling of the design knowledge, automatically acquiring related business field knowledge in the design scheme by means of a semantic retrieval technology and actively providing the business field knowledge to designers, so that the designers can check and refer in time. (2) And (4) middle-layer assistance, namely, in the selection of the optimal scheme, associating the evaluation index with the example scheme based on the prior knowledge to realize multi-target decision. (3) And deep assistance, namely, in the parameter modification process, the automatic modification and suggestion recommendation of the parameters are realized through the constraint of knowledge such as a principle formula, rule experience and the like on the design parameters.

The decision process template modification module 120 includes a decision process module modification unit (decision process template modification unit) 121 for modifying an existing decision process module, a decision process module consistency check unit (decision process template consistency check unit) 122 for checking whether or not the modification of the decision process module satisfies a rule, and a rule base 123 for accessing the decision process module modification rule (decision template modification rule).

The decision process instance creation module 130 comprises a process modeling panel unit 131 for creating a decision process panel (a panel of decision templates), a process modeling tool unit 132 for performing decision process modeling, a process modeling element unit 133 for providing elements required for modeling, an executable knowledge component unit 136 for storing knowledge about the decision process (knowledge of decision templates), a decision solution unit 137 for solving decision problems (decision templates) to generate a design solution, a visualization unit 138 for visualizing expression of decision results (design solutions), a decision process instance library 134 for storing created decision processes, and a decision process management unit 135 for adding, deleting, editing, and querying decision processes. Wherein modeling creates a decision template.

The decision process knowledge management subsystem 200 is configured to implement two functions, namely, a decision process module management function and a decision process element management function, and according to the implementation of the two functions, the decision process knowledge management subsystem 200 includes a decision process template module 210 for storing the decision process module and a decision process element module 220 for storing the decision process element; the knowledge base of the decision process knowledge management subsystem 200 is a configurable knowledge base, i.e., the corresponding knowledge base information attributes are configured according to different knowledge types.

The decision process template module 210 is used for ontology-based meta-design modeling, and comprises a design process template library 212, a stage process template library 213, an event process template library 214, a decision process template library 215 and a task process template library 216; the system decision process template module 210 is a graphical design decision process modeling representation, and includes a design process template, a stage process template, an event process template, a decision process template (second decision process template), and a task process template, for implementing determination of execution order of respective involved decision activities involved in the initial design requirement to the final design specification; the decision process element module 220 is used for storing elements in the decision process, including a process entity library 222, an information knowledge entity library 223 and a system entity library 224.

The decision process template module 210 stores five standard templates of a design process, a phase process, an event process, a decision process (second decision process template), and a task process, a "process template" being a generalized representation of a design activity that enables the transition of product information from one state to another in a computer environment. Each process template comprises one or more conversion networks, and the product system information is perfected by solving design problems related to decisions.

When in use, a user creates a corresponding template, fills the corresponding attribute slot, adds necessary design knowledge and examples, and creates the next template. The method comprises the following specific steps:

designing a process template:

(1) creating a process template example of the type and filling an attribute slot of the process template example; (2) adding a product object instance; (3) adding necessary design knowledge examples and information examples related to a design stage; (4) filling attribute slots of specific system instances based on existing knowledge and information instances; (5) the creation phase supports problem entities and associates them using interface instances.

Stage process template:

(1) creating a process template example of the type and filling an attribute slot of the process template example; (2) creating an event support problem entity under a specific design stage; (3) adding necessary design knowledge examples and information examples related to a design stage; (4) enriching the template examples of the design process of the previous layer based on the results of the design stage; (5) the creation phase supports problem entities and associates them using interface instances.

Event process template:

(1) creating a process template example of the type and filling an attribute slot of the process template example; (2) creating a decision support problem entity and a related task support problem entity under a specific design event; (3) adding necessary design knowledge examples and information examples related to design events; (4) enriching template examples of a previous layer of design stage based on the result of the design event; (5) event support problem entities are created and associated using interface instances.

A decision process template:

(1) creating a process template example of the type and filling an attribute slot of the process template example; (2) creating a decision solving template under a specific design decision, and filling the decision solving template with an example based on the existing information example; (3) creating a task support problem entity under a specific design decision; (4) adding necessary design knowledge examples and information examples related to design decisions; (5) enriching the previous layer of design event template examples based on the design decision result; (6) decision support problem entities are created and associated using interface instances.

Task process template:

(1) creating a process template example of the type and filling an attribute slot of the process template example; (2) adding necessary design knowledge examples and information examples related to design tasks; (3) adding necessary design knowledge examples and information examples related to design tasks; (4) enriching the previous layer of design decision/event template examples based on the design task result; (5) task support problem entities are created and associated using interface instances.

The decision process element module (process element template) 220 classifies process elements into three categories: process entities, information knowledge entities, and system entities.

Process entities represent the major design activity elements for solving a design problem, including "stages," events, "" tasks, "" decisions.

The system entities represent the main input elements for the execution of the design activities, including "system variables", "auxiliary parameters", "analytical relationships", "conditional relationships", and "constraint relationships".

The information knowledge entity represents a relationship between two design activities that provides input and output for the design activity entity.

The generic knowledge management subsystem 300 is used to manage the generic knowledge used in the decision-making process, and includes a decision-making process knowledge module 310 for decision-making modeling and a knowledge tool module 320 for solution and visualization of the decision-making model.

The decision process knowledge module 310 includes a parameter/model base 312 for storing basic information of decisions, a concept solution base 313 for storing concepts related to the decisions, a domain knowledge base 314 for storing knowledge of related disciplines, a decision model base 315 for assisting decision modeling, and an executable operator program (executable computation routine base) 316 for querying and solving the problem of the created decision model.

The knowledge tool module 320 includes a decision model solver 322 for solving the created decision model (consistent decision template), a specialized software tool library 323 for assisting decision optimization, and a visualization tool library 324 for implementing decision result visualization.

Fig. 3 is a flow chart illustrating specific steps in modeling a complex product design, that is, a workflow diagram illustrating a complex product design decision process modeling method, which is a step for explaining the use of a complex product design system from the perspective of a user. Referring to fig. 3, the invention provides a modeling method for a complex product design decision process, comprising the following steps:

step S100: according to the requirements of the design problem, the design problem is defined, including the input and output of the design problem, and the corresponding weight and threshold of each index, which are used for retrieving the first decision process template in step S110 for instance retrieval.

Step S110: the retrieval decision process template (decision process template retrieval module) 110 performs retrieval matching of instance knowledge according to the type and features of information in the input design index, and the retrieval matching process includes a semantic retrieval unit and a feature retrieval unit.

Wherein, step S110 performs matching through semantic retrieval and feature retrieval.

The semantic retrieval unit 111 performs semantic similarity matching calculation with the keywords in the knowledge items stored in the ontology base 112 and labeled by the semantic labeling unit through the word segmentation processing of the concepts and paragraphs in the design index.

Specifically, the word segmentation process is introduced as follows:

the method is characterized in that if the frequency TF of a word in a word sequence is high and the word in other word sequences rarely appears, the word or phrase is considered to have good category distinguishing capability and is suitable for word segmentation.

The IDF formula for calculating a word x is:

where N represents the total number of texts in the corpus, and N (x) represents the total number of texts in the corpus containing the word x.

And counting the word frequency of each word through a TF-IDF formula, giving a weight to each word according to the word frequency, and finally selecting partial candidate words according to the weight to form an expression vector of the knowledge resource.

The semantic similarity matching calculation is introduced as follows:

the design indexes are divided into character type indexes, numerical type indexes, interval type indexes, fuzzy type indexes and inclusion type indexes, and various similarity calculation methods are respectively given.

(1) A character type indicator; the character type index represents performance expectation of a certain aspect of product design, and is usually in a text description form, such as product material performance, use comfort requirement and the like.

Character type index x ═ a ₀ ，a ₁ ...a _n ) And y ═ b ₀ ，b ₁ ...b _n ) Similarity SIM (subscriber identity module) _T The calculation method of (a, b) is as follows:

in the formula: a is a resource instance feature concept vector, and b is a target scheme feature concept vector, and the values of the vector space vector are obtained through a vector space model.

(2) A numerical index; generally refers to a quantitative description of a certain design index, such as reliability requirements, service life requirements, and the like. For the numerical indexes such as x, y and b, the similarity SIM _N The calculation method of (a, b) is as follows:

in the formula: a is the attribute value of the resource instance characteristic x, b is the attribute value of the target scheme characteristic y, and alpha and beta are the lower bound and the upper bound of the partition respectively.

(3) A compartment type index; generally, a size range of a certain index is described, and upper and lower limits are given, such as weight requirements and size requirements of products. For x ∈ [ a, a']，y＝[b，b′]SIM of similarity thereof _I ([a，a′]，[b，b′]) The calculation method of (c) is as follows:

in the formula: a. a 'is the interval attribute value of the resource instance feature x, and b' are the interval attribute values of the target scheme feature y.

(4) A fuzzy index; usually, only the lower limit or the upper limit of a certain index is required, such as the cost of the product, and usually the upper limit is given. For a, max, and f, the similarity SIM _F (x) The calculation method of (c) is as follows:

in the formula: a is the target value of the fuzzy attribute feature, x is the true value of the fuzzy attribute feature, f is the feature attribute, min (f) and max (f) are the lowest and highest threshold values of the fuzzy attribute value, respectively.

(5) An inclusion type index; for restricting the product's compatibility to a particular object or function. For example, x ═ a ₀ ，a ₁ ...a _n Y ═ b ₀ ，b ₁ ...b _n } of object, similarity SIM _C (x, y) is calculated as follows:

in the formula: a is _i Is the attribute value of a resource instance feature x, b _j For the attribute value of the target solution feature y, Count (x → y) represents the sum of the number of times the element in x appears in y.

On the basis of obtaining the similarity calculation of a single technical index, evaluating each design index in an expert evaluation mode and giving a weighted value to obtain a comprehensive similarity value, wherein the calculation formula is as follows:

SIM(C ₁ ，C ₂ )＝ω _T SIM _T +ω _N SIM _N +ω _I SIM _I +ω _F SIM _F +ω _C SIM _C

in the formula: omega _T 、ω _N 、ω _I 、ω _F 、ω _C Respectively represent similarity weights of a character type, a numerical type, a region type, a fuzzy type and an inclusion type index, and the sum of the similarity weights is 1.

Ontology repository 112 stores and updates relevant domain knowledge from time to time. The domain knowledge refers to knowledge such as standard specifications, patent documents, design manuals and the like related to the business domain in product design. The function is as follows: the semantic retrieval technology automatically acquires the related business domain knowledge in the design scheme and actively provides the knowledge to designers, so that the designers can check the knowledge in time.

The feature retrieval unit 113 performs similarity matching with the example feature information stored in the related art index library according to the input index information and the corresponding weight and threshold.

The similarity matching method is introduced as follows:

the similarity calculation result has a threshold value, which is set by a designer. A specified number of instances that exceed the threshold will constitute a set of similar instances as the initial solution set for the current design problem.

For example, the comprehensive similarity threshold δ is set to 0.6, and the number of candidates is set to n is set to 3, that is, the first 3 instances with the comprehensive similarity greater than or equal to 0.6 are calculated to form a similar instance set, so as to perform matching.

Step S115: judging whether the template in the decision process template base (decision process example base) can be reused (the judgment standard is a set similarity threshold), and executing the step S120 when the existing template meets the reusability requirement; otherwise, step S130 is performed.

The judgment reuse is introduced as follows:

the system judges according to the set threshold and the similarity, and if the set threshold is exceeded, the system is judged to be reusable; otherwise it is not reusable.

Step S120: and modifying the first decision process template according to the actual situation of the design problem, so that the template can be matched and applied to the design problem.

The modification criteria and procedures are described below:

after the optimal similar example is obtained, in order to check whether the optimal similar example meets the design requirements, the system verifies the target scheme, namely, whether the optimal similar example meets the design requirements is compared through the mapping relation between the design requirement indexes and the design parameters. For parameters that do not meet the design requirements, further modifications are needed to make the final solution meet the actual design requirements. Through the inspection process of the previous step, parameters which do not meet the design requirements in the target scheme, namely parameter sets which need to be modified, can be obtained; and determining the modification sequence of the parameters to be modified by means of association rule knowledge existing among the design parameters, modifying the parameters according to the sequence, obtaining modification opinions of the parameters at the same time, and finally obtaining the final design scheme.

The first decision process template role is introduced as follows:

the first decision process template comprises five blocks of design, stage, event, decision and task, which are also core innovation points of the invention, and the reusable information and knowledge in the decision workflow design can be acquired, expressed and stored through different defined types of process templates, so that the efficiency and the efficiency of the decision workflow design are increased. The design of a process template involves the enrichment of product information, i.e., the determination of product design specifications that meet customer requirements and design requirements.

The logical association of the first decision process template with the design problem is introduced as follows:

as shown in FIG. 4, product design is a process that enables information interaction between process models and product models. The product model can be decomposed into product whole, parts and parts, and the corresponding information is stage, event and information respectively. The process model and the product model can be respectively abstracted into a meta-model composed of different object concepts such as rules, decisions, activities, constraints, relationships, entities and the like, and jointly form product design knowledge; from the knowledge level, a cognitive behavior belonging to a particular problem is designed, and cognition can be described or interpreted as problem goals, actions, knowledge, and rational behavior. Therefore, design is the rational behavior of three kinds of knowledge, namely design process, product system and design problem, on a given target through correct and ordered activities.

The design process is to realize the information conversion from the product design requirement to the design specification through various design activities. And realizing the mapping relation between the product model and the design process by establishing a first decision process template.

Step S130: creating a first instance of a decision process template, recreating a new decision template in the decision process template module 210, the template matching the design issue, the creation comprising:

step S212: a design process template is created, which is a collection of product design process activities that focus on and capture all relevant design specification information for a certain product or system, such as the composition form, behavior, geometry, functionality, etc. of the product system.

Step S213: a phase process template is created that pertains to a system level design activity that corresponds to the capture of organizational information such as the decomposition and planning of event activities.

Step S214: an event process template is created that focuses on and captures organizational information such as decision and task activity decomposition and planning under a certain event.

Step S215: a decision process template (second decision process template) is created that requires attention to and captures relevant design information such as specific alternatives, system variables, bias variables, objectives, constraints, boundaries, objective functions, etc. for a certain decision supporting mathematical model.

Step S216: a task process template is created that focuses on and captures the inputs and outputs of the basic design information and the execution relationships between the two, such as computing some function relationship value.

Among the 5 types of process templates, the design process template belongs to the top-level design, the information conversion from product design requirements to design specifications is realized through various design activities, the design key points of the stage and event process templates are the division and planning of design support problems, and the design of the task and decision process template is focused on the formulation and solution of a certain specific design problem.

Here, the design process can be divided into multiple stages, and the overall input and output of the design problem needs to be determined; a "phase" consists of a set of "event" instances, which are defined by a series of related instances of the "decision" and "task" subclasses. The designer models the full-cycle process of a particular system design by instantiating these subclasses, as shown in FIG. 5.

Through steps S212-S216, a decision-centric design template of the matching design problem is defined and generated, a new first decision process template is obtained (the process of specifically constructing five templates is as described above), and step S110 is executed again.

As shown in fig. 6, the relationship of five templates is explained by way of a heat exchanger example.

The design modeling of the complex product is carried out by firstly constructing a design process template from the customer requirements. The design is divided into three large phases (P): design concept, design manufacturing, and design maintenance. The three phases together complete the conversion from system level input information (customer requirements) to system level output information (full lifecycle design specification knowledge). Where I represents information describing the inputs and outputs of the design campaign entity. When the design concept is expanded, the design concept is divided into a plurality of design events (E), and each event transmits corresponding information. FIG. 7 represents the relationship of events and tasks/decisions; each event is broken down into multiple tasks and corresponding decisions.

Step S134: the updated first decision process template is stored in the decision process instance store 134.

Step S122: a first decision process template consistency check is performed to check whether the existing decision template matches the input design problem (obtained by similarity calculation) based on the rule knowledge in the rule base 123.

Step S136: a mathematical model of the decision (decision model, i.e. decision template) is constructed based on the relevant knowledge of the decision process knowledge module 310 and the information of the first decision process template.

The method for constructing the mathematical model comprises the following steps: and characterizing the decision workflow of the design process through the constructed stage, event and task template. A plurality of tasks are specified, including extracting targets and constraints from design requirements, determining influence factors, sorting parameter information and the like. Mathematically characterizing the design problem in a decision process template: and extracting decision targets, variables and constraint information, and solving by adopting a solver.

And (3) logically connecting: and converting the design problem into a corresponding mathematical model through the one-by-one decomposition of stages, events, tasks and decisions.

Step S317: the constructed decision model is solved using a decision model solver 322 in the knowledge tool module 320.

Step S318: according to the decision solution result of step S317, the result is visualized through the specialized software tool library 323 and the visualization tool library 324 in the knowledge tool module 320.

Step S140: judging whether the solution scheme is satisfied or not according to the visualization result, and if so, executing the step S150; if not satisfied, the process returns to step S120 to re-modify the first decision-making process template.

Step S150: and outputting a satisfactory design result.

The workflow of the complex product design decision process modeling method and system of the present invention is further described below using a shell and tube heat exchanger as an example.

A heat exchanger (or heat exchanger) is a heat transfer device used for internal thermal energy transfer between two or more liquids at different temperatures. A common heat exchanger is of the shell and tube type, shown in fig. 8 as a single pass straight tube type. Shell and tube systems are widely used in industrial process applications (e.g., power generation, chemical engineering, machining, etc.) for heat exchange, such as oil coolers, condensers, feedwater heaters, etc., due to their ease of manufacture. The shell-and-tube heat exchanger mainly comprises a tube body, a baffle, a shell, a tube plate and the like.

The shell and tube heat exchanger design process primarily considers the following design factors: 1. thermodynamic design-ensuring heat exchanger performance requirements and meeting pressure drop requirements for each tube bundle fluid; 2. mechanical design-providing the integrity of mechanical conditions such as design specifications and operating requirements; 3. cost and design of manufacturing and construction. The above factors are mostly interdependent and therefore need to be considered at the same time in the design to achieve the most satisfactory heat exchanger.

Step s 100: and (4) design problem definition. The design object of the scheme is a shell-and-tube heat exchanger, which comprises a tube body, a baffle, a shell, a tube plate and the like; three indexes are considered during design: pressure drop requirements, mechanical structure, and cost.

Step s 110: a first decision process template is retrieved. And searching in a decision process example library by taking the shell and tube heat exchanger as a core.

Step s 115: judging whether the template in the decision process example base can be reused, and executing the step s120 when the existing template meets the reuse requirement; otherwise step s130 is performed.

Step s 120: and modifying the first decision process template according to the actual index requirement of the design problem and the new technical requirement, so that the template can be matched and applied to the design of the shell type heat exchanger.

Step s 130: a first decision-making process template instance is created, and a new decision-making template is created in a decision-making process template module, the template matching the design problem.

Step s 212: a design process template is created, which is a set of product design process activities that focus on and capture all relevant design specification information for a certain product or system. The purpose of the design process template is to store information about the customer's needs and to record a description of the product object's knowledge of specific specifications on the design timeline. In this example, the customer needs to design a heat exchanger for a small power plant thermal system to achieve design goals of minimum heat transfer area, minimum pressure drop, maximum heat transfer efficiency, minimum size, and minimum cost.

Step s 213: a phase process template is created that divides the design of the shell and tube heat exchanger into three main design phases, namely a "design concept phase", a "design manufacturing phase", and a "design maintenance phase". The design concept stage mainly completes the design aim of converting the customer requirement into the engineering design requirement of the product and realizes the product design specification knowledge which can be used for design, manufacture and design maintenance; in the design and manufacturing stage, designers need to seek engineering design solutions facing the manufacturing and construction stage to ensure the cost and manufacturability of the product; during the design and maintenance phase, the designer takes into account the wear of the equipment and the effort and cost required for maintenance.

Step s 214: creating an event process template, opening a design concept stage, setting specific design events of the stage, and developing events from design requirements ₀ As a starting point, the customer requirements are converted into product design requirements, including determining system design target values or design intervals such as heat conversion efficiency and pressure drop. The generated design requirement specification document will be used as a concept design event E ₁ The input information of "is the basic concept"Provides system level design requirements; also "concept design event E ₁ "the generated related design information and knowledge will be the subsequent" preliminary design event E ₂ And detailing event E ₃ "provide design input.

Step s 215: creating a decision process template (second decision process template) which needs to pay attention to specific alternatives of the shell switch, system variables, deviation variables, targets, constraints, boundaries, objective functions and the like; at concept design event E ₁ "the designer can determine some suitable system attribute concepts (such as spiral pipe, casing, housing) by means of the" preliminary selection decision "activity; based on the identification of system objectives and constraints in the design requirements and the determination of design variables for system performance, the designer may then perform a "selection decision" activity, i.e., solve the "selection decision" by executing the associated decision template to obtain the most appropriate conceptual solution that satisfies the design requirements determined in the input information.

Step s 216: creating a task process template, wherein the task process template focuses on and captures input and output of basic design information and an execution relation between the input and the output, such as calculating a function relation value; as in the thermal analysis of the shell and tube heat exchanger system design, the designer needs to calculate the heat transfer coefficient to obtain the design target heat transfer area for the system.

Through steps s212-s216, a decision-centric design template of the shell heat exchanger design problem is defined and generated, a new first decision-making process template is obtained, and step s110 is re-executed.

Step s 134: the updated first decision-making process template is stored in the decision-making process instance store 134.

Step s 122: and (4) checking the consistency of the template in the first decision process, and checking whether the existing decision template is matched with the input design problem or not according to rule knowledge in a rule base.

Step s 136: and constructing a decision mathematical model according to the relevant knowledge of the decision process knowledge module and the information of the first decision process template.

Step s 317: the constructed decision model is solved using a decision model solver 322 in the knowledge tool module.

And step s318, according to the decision solving result of the step s317, visualizing the result through a professional software tool library and a visualization tool library in the knowledge tool module.

Step s 140: judging whether the solution scheme is satisfied or not according to the visualization result, and if so, executing the step s 150; if not, the process returns to step s120 to re-modify the first decision process template.

Step S150: and outputting a satisfactory design result.

Through design activities, interfaces, and information related to problems, products, and processes associated with the design of split shell and tube heat exchanger systems, designers can easily combine and reconfigure design processes with existing knowledge, as well as perform operational activities such as creation, update, and reuse of decision workflows.

The invention provides a complex product design decision method and a complex product design decision system which overcome the defects that the design of the current complex product is designed by taking human experts as the leading factor, the technical experience requirement on designers is higher, the design efficiency is low, and the design method in the prior art is lack of design mainly based on a decision process. The invention aims at the requirement and the characteristic of 'meta-design' of a decision workflow in the design of a complex product, constructs a modeling and representing method capable of describing the process behavior of a designer in the design decision process, and particularly relates to a decision problem modeling method in the design process.

The invention provides a method and a system for modeling a decision process of complex product design, which is a design modeling and representing method taking a decision as a center, the design process of the complex product is characterized by taking the decision as the center, a set of universal decision process templates are provided, the templates have reusability, the method and the system are suitable for complex products with more reference to the previous design, the reusable information and knowledge in the design of decision workflow can be acquired, represented and stored through different types of defined process templates, the efficiency and the efficiency of the design of the decision workflow are increased, and the research and development period is shortened. The complex product design decision process modeling system carries out first decision process template retrieval and judges whether the template can be reused according to the input design problem definition, then modifies or creates a corresponding first decision process template example, and embeds the example into a knowledge component after consistency check, so that the template can be repeatedly called in subsequent similar design. And finally, solving and visualizing the constructed decision workflow. The invention also provides a set of universal decision process templates, the design process of the complex product is represented by taking a decision as a center, and the templates realize the acquisition, representation and storage of reusable information and knowledge in the design of the decision workflow.

In the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims

1. A complex product design system is characterized in that the system comprises a design problem input module, a decision process template retrieval module, a judgment module, a decision process template modification module, a decision process instance creation module, a decision process template module and a knowledge tool module;

2. The complex product design system of claim 1, wherein the decision process template retrieval module specifically comprises a semantic retrieval unit, an ontology library and a feature retrieval unit;

the ontology library is used for accessing the decision template;

3. The complex product design system according to claim 1, wherein the decision process template modification module specifically comprises a decision process template modification unit, a decision process template consistency check unit and a rule base;

4. The complex product design system of claim 1, wherein the decision process instance creation module specifically comprises a process modeling panel unit, a process modeling tool unit, a process modeling element unit, an executable knowledge component unit, a decision solving unit, a visualization unit, a decision process management unit, and a decision process instance base;

5. The complex product design system of claim 4, further comprising a decision process element module;

6. The complex product design system of claim 4, further comprising a design decision module, a design output module, and a return module;

7. The complex product design system of claim 1, wherein the decision process template module specifically comprises a design process template library, a stage process template library, an event process template library, a decision process template library, and a task process template library;

8. The complex product design system of claim 1, wherein the knowledge tool module specifically comprises a decision model solver, a specialized software tool library, and a visualization tool library;