Research On Knowledge-driven Conceptual Design Method Of Mechanical Products Under Cognitive Difference

Modern product design is the result of the synergy between users and designers' subjective cognition and objective knowledge.Its essence is innovation,and its core lies in the conceptual design stage.Conceptual design is a knowledge-intensive work,and knowledge resources must be used as strategic resources to drive product design innovation.For the design of mechanical products,the function of the product is the most basic requirement of the user,and the appearance form is the design upgrade of the mechanical product.Therefore,the core problem of this paper is to realize the conceptual design of mechanical products that better meet the functions and user needs,so as to improve the efficiency and innovation of mechanical product design.To achieve the design innovation of mechanical products,designers must first ensure the user's cognitive psychology of product demand,use the "Internet +" environmental advantages,and adopt an efficient method to reduce the impact of perceptual factors and rational factors on the design process.In view of this,it is necessary to take the user's demand for product manufacturing as the starting point,and in-depth study of knowledge-driven mechanical product concept design related theories and methods from the inside and outside of the product in a dual-drive design form to solve the following problems:1.Knowledge acquisition and knowledge management issues for mechanical product customization under the “Internet +” environment.How to accurately meet the needs of product design according to the different perceptions of users and designers on mechanical products,combined with individual needs and design features,and build a knowledge base of "Internet +" mechanical product custom design,which is to solve "Internet +" basic innovation issues in custom design.2.Intelligent design problem of "Internet +" mechanical product personalized requirements customization.How to transform the uncertain and implicit demand intelligence in the "Internet +" environment into the product design elements needed for design,so as to realize the intelligent design of mechanical products,which is the key issue to improve product design efficiency and design success or failure.3.The problem of constructing the mechanical product evaluation system and the solution convergence problem of the user's deep participation.How to construct a scientific and comprehensive evaluation system for mechanical product design according to the different design positions of users and designers,and form a conceptual design pattern of deep participation of users for different mechanical products,so as to accurately recommend innovative design solutions for mechanical products that meet user needs.This is an effective way to improve the satisfaction of design requirements.Based on the research of related product conceptual design at home and abroad,this paper takes advantage of the environmental advantages of “Internet +”,focuses on the cognitive differences between users and designers,and uses knowledge as the driving source to incorporate intelligent methods of knowledge transfer.In the process model of conceptual design of mechanical products,which is deeply involved in the user,combined with the research work and results of this paper,a mechanical product concept design knowledge assisted prototype system is constructed.Based on the system,a fast research approach is explored for the conceptual design of mechanical products to improve the reliability of design requirements and ensure that the designed mechanical products meet the diverse needs of users.The main research results of this paper are as follows:1.A method of constructing PFBS knowledge base for knowledge flow in product concept design is proposed.From the perspective of user and designer's cognition in conceptual design,design knowledge is divided into two categories: designer's design experience and user's image cognition.The concept of knowledge flow is introduced to construct PFBS knowledge base of product structure design module and PFBS knowledge base of product form design module.The knowledge flow is used to explain the design type of the product in the product structure design(user-driven product design,retrofit design and creative design).Finally,the conceptual design process model is constructed.2.An inference mapping method for multi-factor knowledge solving in structural concept design is proposed.Guided by user needs,the two innovative design types,namely,transformative design and creative design,are proposed in the process of function solving,and the inference mapping strategy of structural conceptual design knowledge solving is proposed.Researching the fuzzy level Kano model and QFD integration method to obtain the product function requirements that users expect innovation;according to the three representations of functions in the knowledge base,different methods are used to solve the product structure to realize the direct mapping of function-structure;the functional heuristic reasoning method for researching behavior solving is to implement the functionstructure indirect mapping with behavior as a bridge,and intelligently infer the carrier structure of product function to expand the designer's design thinking.3.The design element identification method of image-driven design in morphological concept design is proposed.In order to reduce the cognitive difference between users and designers,and to ensure the practicality of user design knowledge,a method of destructuring the morphological elements of products using cognitive multi-dimensional is proposed.In addition,a combination of factor analysis and cluster analysis is used to extract the user's representative image lexical pairs.Based on the idea of perceptual engineering and the improved BP neural network,a user image prediction model oriented to multi-dimensional perception is established to explore the mapping relationship between key product design elements and user image to guide the designer's product design.4.Design scheme convergence method of TOPSIS based on grey correlation rough number is proposed.Combined with the participation psychology of modern users,this paper proposes a TOPSIS comprehensive evaluation method based on grey correlation rough number to evaluate the adaptability of design schemes,so as to reduce the collection of product design schemes,and quickly recommend the product design scheme of the user's perceptual needs.