Research On Model Of Control And Grey Evaluation Of Quality Cost Based On Qality Function Deployment

Quality has become one of the core factors for almost all manufacturing and service companies that aim to win sufficient orders. Therefore, improving quality is considered to be one of the important strategies to attain customer loyalty in today’s complex global competitive environment. Studies concluded that any serious endeavour to improve quality will lead to an increase of cost of the product or service since improving quality has its own costs. Therefore, how to control the costs while improving the quality to meet the customer demand has become the urgent and significant practical problems faced by government, business and academia.Quality Function Deployment is a product design method that driven by customer demand. It can turn the unsure customer need into determined technical characteristics. Kano theory can identify the multidimensional needs of the customers. Integration of Kano model and QFD will help to develop the products that meet customer needs depending on the different quality characteristics. Failure Mode and Effects Analysis, as a forward-looking approach to take reliability analysis and safety evaluation can better complementary with QFD to improve the product design and development. Grey system theory as the research method of uncertain systems can help to study the relationship between quality level and costs.This study established the quality costs control and grey evaluation model based on QFD. It utilizes the method of QFD and Kano to turn the customer needs contained quality cost factors into product technical features and components technology. For related parts that analyze the failure mode and effect with the method of FMEA theory to control the quality stability of the product. At the same time, take advantage of the gray system theory to construct linear regression model of the quality level and costs, and use it to predict and control the cost of quality. Also, the study applies the model to a motor company’s product design improvements and achieves significant improvement effect.Achievements of this paper are as follows: First, proposed the quality costs control and grey evaluation model based on QFD.Second, proposed the concept of loss cost importance based on Kano model, which expand the study of QFD.Third, proposed the RPN gray evaluation method based on QFD and entropy method, improving the FMEA theory.Fourth, build the gray linear regression model of quality level and costs using gray system theory.Fifth, applied the model into process of a motor company’s product design and development.