Methodology Of Building Robust Product Platform For Complex Products

The mode of product development based on product platform can satisfy the ever-changing external demands with as little as possible internal diversity, and reduce cost and risk, by making full use of the existing system resources. Complex products show numerous complexities in the customer demands, structure, technique, manufacture, management and other aspects, which results in multifarious design parameters and constraints, uncertained design results, long lead time, high risk and cost. Then it is rather important for complex product design to use existing mature technique and components fully, so as to enhance the reliability of the design and achieve the anticipated design effect. In brief, the product platform building for complex product has more importance than that for simple product. At the same time the product platform built for complex product should be robust to adapt greatly uncertain application environment.By comparing the aim of product platform design with that of Robust Design, it indicates that the process of product platform design in nature is robust design. Traditional Robust Design fails to deal with the product family design, so the concept of Robust Design is extended here, on which the robust design model for product platform design is put forward. The model indicates that the process of robust product platform design is a process of performing sensitivity analysis to analyze the impact of the change of design variables on the structure variables of the target product family.Based on the model of robust design, a flowchart of robust product platform design for complex products is presented, which includes design variables drawing and analysis, series division, modularization, and robust parameter design of scaled module. According to the characteristic of complex products, by using block design in Experimental Design for reference, product platforms could be serialized for increasing commonality. Additionally, the demands of robustness are carefully considered in each step of product platform design.Two key issues in the process of robust product platform building for complex products are emphasized on: (1) the way of design variables identification and selection is researched on. First, fishbone diagram is introduced to identify and analyze the factors result in the changes of the product structure parameters, and to reject some artificial reason result in unnecessary modification of design. Second, the method of rough number is improved to perform importance evaluation for customer demands and reduce unimportant demands. Third, to obtain the key parameters as the reference index for series division, a method based on sensitivity analysis from customer requirements to technical parameters and further to product components is advised. (2) The approach of acquisition and description of the structure variable of product platform is studied on. The structure variables are defined as entity modules or structure parameters. The entity modules are divided into standard modules, flexible modules, scalable modules, virtual modules and decomposable modules through sensitivity analysis. And the initial modules are obtained by decomposing the product with reverse fishbone diagram in the interior of each series. Additionally, the parametric product platform is built for scaled modules, and the way of parameter identification is put forwards for single-valued, multi-valued and scaled value parametric platform.