1. Systematic design method The main feature of the systematic design method is that the design is regarded as a system consisting of several design elements. Each design element has independence. There are organic connections among the elements, and they are hierarchical. All the design elements are combined. After that, you can accomplish the tasks required to design your system. Due to the different perspectives of each designer's research issues and the focus of the considerations, there are also differences in the specific research methods used in the design of the scheme. Here are some representative systematic design methods. 1.1 Design Element Method The "product solution" is described by five design elements (functions, effects, effect carriers, shape elements, and surface parameters). After the five design element values ​​of a product are determined, all the features and characteristic values ​​of the product are determined. There are also design scholars in China who have used a similar method to describe the original understanding of the product. 1.2 Graphical Modeling The functional structure of the product and its related abstract information are described by a well-defined graphic, which realizes the graphical modeling of the system structure and functional relationship, and the connection between the functional layers. The design is divided into two aspects: auxiliary method and information exchange. The information analysis method can adopt graphic symbols, rich semantic model structure, can describe integration conditions, can divide constraint types, and can realize any combination of relationships. The design method solution is integrated with information technology to realize the graphical modeling of the information relationship between different abstract layers in the design process. 1.3 “Concept†– “Design†Method The product design of the product is divided into two stages of “conception†and “designâ€. The task of the "concept" phase is to seek, select, and combine the original understanding that meets the design task requirements. The work in the “design†phase is the original understanding of the concrete realization of the concept phase. 1.4 Matrix Design Method In the scheme design process, the "requirement-function" logic tree ("AND" tree) is used to describe the relationship between requirements and functions, and the functional design solutions that meet the requirements are obtained to form different design schemes. Then, according to the "requirement-function" logic tree, a "requirement-function" association matrix is ​​established to describe the complex relationship between the functions required to meet the requirements, and to express a one-to-one correspondence between requirements and functions. 1.5 bond diagram method The functions that make up the system components are divided into various types such as generating energy, consuming energy, transforming energy forms, and transferring energy, and borrowing the functional solutions of the bonding graph expression components, and hoping to combine the function-based model with the bonding graph to realize the functional structure. The automatic generation and automatic conversion between the functional structure and the bond graph seeks a way to generate multiple designs from the bond graph. 2, structural modular design method From the perspective of planning products: when defining the design task, based on the functional product structure, refer to the existing product solution to describe the design task, that is, consider whether there is a corresponding product solution for each sub-task when decomposing the task, so that Eliminate possible contradictions in design tasks during the product planning phase, early forecast production capacity, cost, and plan adjustability during development design, thereby increasing design efficiency and design reliability while reducing the cost of new products . It is believed that most functions in special machinery can use existing product solutions, and the special functions with new solutions are only a few. Therefore, the use of functional product structure in special mechanical design is very beneficial for evaluating the design and manufacturing risks of special machinery. On the basis of product function analysis, the product is decomposed into one or several modular basic structures with certain functions, and different products are built by selecting and combining these modular basic structure groups. These basic structures can be parts, components, or even a system. The ideal modular basic structure should have standardized interfaces (joins and mates), and be serialized, generalized, integrated, hierarchical, flexible, economical, interchangeable, compatible, and relevant. Combining software component technology and CAD technology, China combines deformation design and combination design. According to the principle of hierarchical modularization, the machining center machine tools are divided into product level, component level, component level and component level from large to small, and utilize expert knowledge. And CAD technology combines them into functional modules of different varieties and different specifications, and then combines these functional modules into different processing center overall schemes. Designing as a tool for selecting the mechanical structure of the variation, it is proposed to carry out the complete and structured arrangement of the solution elements of the design to form a catalogue of the solution design. And listing additional information about each solution in the Solution Design Catalog is very useful for design engineers to choose solution elements. According to the coupling characteristics of mechanical components, they are classified into four types: 1) components with direct positioning between components and self-adjusting; 2) structurally common assemblies; 3) with nested structures and embedded The coupling of the sleeve element; 4) the connection of the modular structure and the modular element. 3. Design method based on product feature knowledge The main features of the product-based knowledge design method are: using the computer-recognizable language to describe the characteristics of the product and the knowledge and experience of the experts in the design field, establish the corresponding knowledge base and inference engine, and then use the stored domain knowledge and established The reasoning mechanism realizes the design of computer aided products. The design of the mechanical system is mainly based on the characteristics of the product, as well as the knowledge and experience of the experts in the design field to carry out the push and decision, and complete the type and number synthesis of the organization. To achieve this stage of computer-aided design, it is necessary to study the automatic acquisition, expression, integration, coordination, management and use of knowledge. To this end, domestic and foreign design scholars have done a lot of research work on the automated processing of mechanical system design knowledge, and the methods used can be summarized as follows. 3.1 Coding method According to the "sports conversion" function (referred to as function element), the organization is classified, and the code is used to describe the function element and the organization category, thereby establishing the "institutional system design expert system" knowledge base. On this basis, the combination of binary logic reasoning and fuzzy comprehensive evaluation principle is established, and the reasoning mechanism of the "expert system" is established and used in the design of four-station special machine tools. Mixed expression of knowledge For the design of complex mechanical systems, it is especially suitable to describe all kinds of knowledge in the design by using mixed knowledge representation. This has been the consensus of many design scholars in China. In the development of complex product design intelligent decision support system (DMDSS), knowledge representation methods such as rules, frameworks, processes and neural networks are organically combined to adapt to the description of different types of knowledge in the design. A variety of single knowledge expression methods (rules, frameworks, and procedures), according to object-oriented programming principles, use the slot of the frame to represent the attributes of the object, use rules to represent the dynamic characteristics of the object, and use the process to represent the processing of knowledge to form a Hybrid knowledge expression type, and successfully developed "object-oriented numerical control portal milling machine gearbox design intelligent system GBCDIS" and "gearbox structure design expert system GBSDES". 3.3 Leverage knowledge-based development tools In the CAD system of the coupling, using the knowledge-based development tool NEXPERT-OBJECT, the object-oriented design method database is created by means of the object-oriented method, which provides the designer with the scheme design and structural design of the coupling. A broad and reliable design methodology spectrum. NEXPERT is used to describe the content of linear guide design that needs to be designed based on knowledge, thus seeking a knowledge-based solution and developing an expert system for linear guide design. 3.4 Design Catalog Method Constructed a three-level progressive design catalogue of “functional modulesâ€, “functional meta-solutions†and “institutional groupsâ€, and used the three-stage progressive design catalog as the knowledge base and development design of the mechanical transmission principle scheme intelligent design system. Auxiliary tools. Instance-based approach In the knowledge base of developing design expert system, basic predicate is used to describe design requirements, design conditions and selected schemes, framework structure is used to describe "engineering examples" and various "concept entities", and case-based reasoning techniques are used to generate candidate solutions. Come to match the design requirements of the product. 4, intelligent design method The main features of the intelligent design method are: according to the design methodology theory, the development and design of products, the conception of products, and the description of products by means of 3D graphics software, intelligent design software and virtual reality technology, as well as multimedia and hypermedia tools. structure. While using the mathematical system theory, the system engineering theory, product design technology and system development methodology are considered, and the multimedia development system software suitable for the initial use of product design is developed. The entire development process of the product is summarized as "product planning", "development" and "production planning", and the existing CAD cutting-edge technology - virtual reality technology is fully utilized. 1) Product Planning - Conceiving products. Its mission is to determine the external characteristics of the product, such as color, shape, surface quality, ergonomics, etc., and to present the original idea in a CAD stereo model, to create a simple model that reflects the shape of the entire product, the model can be virtual Established in the environment and able to quickly generate different shapes and colors. 2) Development - design products. At this stage, according to the principle of “system synthesisâ€, the solution elements are configured and integrated on the three-dimensional model. The solution elements have different meanings according to different design goals: they can be basic elements such as bolts, shafts or hubs, etc. Elements, such as mechanical, electrical, electronic components, control technology or software consisting of transmission systems; can also be requirements, characteristics, shapes, and so on. After the key solution elements of the implementation function are configured on the stereo model, the configuration of the product (the relationship between the solution elements in the design model) can be analyzed. The product configuration analysis is important for the comprehensive "product planning" and "development" results. means. 3) Production planning - processing and assembly of products. In this stage, the application of CAD technology in the assembly process is mainly discussed. It is proposed to display the assembly process of the solution elements in the corresponding position by computer image, that is, to reveal the relationship between the shape and the assembly through the virtual assembly model, thus finding the difficulties and problems. And find out how to solve the problem, and believe that the application of CAD technology in the three stages of product development, the integration and analysis of the design process can be continuously alternated in "product planning", "development" and "production planning" get on. Therefore, the problems existing in each stage can be found earlier, and the products are continuously refined and improved in the development process. Shangqiu Jinda Tools Co.,Ltd , https://www.jindameasur.com