Research On Optimization Of Product Design Process Based On Value Analysis

Manufacturing industry is an important field of "innovation-driven,transformation and upgrading" in China's economy.Improving the ability of complex product design is an important measure to narrow the gap between China and developed countries in manufacturing level,and to promote China from a big manufacturing country to a powerful manufacturing country.The optimization of design process is an important way to improve the ability of product design.With the continuous innovation of technology,modern products are becoming more and more complex both in function and structure.The design process of complex product is a complex system with multi-objective,multi-constraint and multi-influence factors with strong information coupling and relevance.So,it is a system engineering to analyze and optimize the design process of complex products.The traditional optimization and control methods were not flexible in the development and application in engineering practice,and the application effect is not ideal,due to the constraint of the scale of the product structure,the complexity of the technology composition and the dynamic uncertainty of the design environment.The "lean thinking" regards product design process as a process with value creation,and it emphasizes that the purpose of process optimization is to improve the ability to achieve maximum product function at the lowest cost.This ability reflects the value of the process.The research of the connotation,composition and quantitative method of "process value",and the application of it in research on optimization and control of product design process,can improve the quality and process efficiency of product design.It has important theoretical significance and application value to improve the innovation ability of the enterprise.Aiming at the problem that the concept of value in product design is not clear and is difficult to quantify,this paper deeply researches the conception of "process value".The scientific content of process value is revealed from two aspects:value adding and value transferring.The hierarchical mapping from customer requirements to design process is proposed,and the quantitative model of process value is established.Based on the system evaluation method,the quantitative model unifies the dimension of each element of process value.It reflect the overall performance of complex product design process,and supports process simulation,prediction and optimization.The feasibility of the model is verified by its application in an enterprise example.The traditional optimization methods of product design process are insufficient in the versatility and flexibility of the model.This paper discusses the quantitative expression of the overall performance of the design process using process value,proposes a general optimization model based on process value,and gives the selection of the variables,parameters and constraints of the model.The model can solve different design process optimization problems by combining constraints and optimization variables according to the environment of enterprises.This paper analyzes the influence of the design process structure on the performance of the process,and constructed the optimization model to obtain the optimal process structure.The genetic algorithm is proposed to solve the problem.Through an enterprise example,the application of the optimization model is expounded,and the validity of the model is verified.It is difficult to analyze and optimize the design iteration process due to incomplete information or information dependence between activities.The rework rate is used to describe the information dependence between activities.The evolution regularity of activity effectiveness under different conditions is studied,and the effectiveness-driven model of iteration process with coupling design activities is constructed.The model is suitable for all types of iterations in the design process,and can be used to predict and analyze the effect of the iteration process.The quantitative model of process value is revised according to the evolution regularity of activities.The overlapping optimization model is proposed to obtain the optimal overlapping rate.An improved genetic algorithm is proposed.The model takes overlap rate as optimization variable,and it is suitable for all execution modes of design processes.The model is applied to the enterprise example to verify its feasibility and application effect.In view of the problem that the traditional design process models are difficult to analyze the dynamic characteristics of the design process of complex product.and to support dynamic simulation and optimization of design process.this paper analyzes the system dynamics characteristics of the complex product design process.The dynamic model of complex product design process based on system dynamics is established.The boundary and the overall structure of the process system dynamics model with its subsystems are studied,and the dynamic equations are established.The SD model is tested from the structure adaptability and behavior adaptability,the change rules of the process value are analyzed,and the dynamic characteristics of the design process are researched.The model can realize the dynamic simulation of complex product design process,and support the dynamic optimization of the process with simple modeling process.Due to the large number of influencing factors in complex product design process,process planning and control are very difficult.The SD model of design process is used to analyze the influence of internal and external uncertainties on the dynamic characteristics of the complex product design process.Take a compressor design project as an example,the SD model is used to dynamic simulation of the design process.The simulation results can provide support for process optimization.Dynamic optimization of complex product design process based on dynamic simulation is studied.