Quality Function Deployment

Quality Function Deployment (QFD) is a formal technique for deriving a product specification. As with many of the other tools and techniques used during the product introduction process, it is a team-based approach that focuses on reducing time to market and making sure that the product is produced "right first time". In the case of QFD this is achieved by ensuring that the product which is designed is the product that the customer wants. We do this by finding out from the customer what is wanted, and then translating the voice of the customer into prioritised requirements at every stage of the product introduction process.

QFD is generally applied in four phases. Within each phase, output features are derived from the input, and the relationships between output and input plotted in a matrix. Numerical values are then allocated to the relationships, so that the output can be prioritised. The most significant outputs from each phase, in terms of features or processes which are important to the customer, difficult to achieve, or are in some way novel, are passed as input to the following phase. This ensures that points that need to be addressed are kept in focus, and all decisions can be traced back to an identified customer need.

QFD is a detailed planning technique aimed at translating the voice of the customer into specifications at each major stage of the product development process.

• QFD1 - Product Planning
• QFD2 - Part Planning
• QFD3 - Process Planning
• QFD4 - Production Planning

Manufacturing industry

The four phase model was developed for manufacturing industry, where the same organisation is responsible for both design and manufacture of a product. This is the situation to which it is best suited.

Process industries

For continuous process industries, such as food or chemical manufacturing, the four phase model requires refining to make it more appropriate. In many cases in these industries both the product design and the process are directly related to the satisfaction of the design requirements. It is therefore more logical to combine these on a single QFD 2/3 chart, instead of treating them sequentially.

Service industry

Service industries such as banking or retail can use the early stages of QFD in the same way as manufacturing. These industries still have "products" which have to fulfil customer requirements. Delivering the service requires processes, which can be defined using QFD.

QFD in the development of software

A later development in the QFD methodology is its application to the development of software. As with its use in process industries, the four phase model may not be the most appropriate, and alternatives have been suggested. One approach is to use QFD 1 in the normal way to map design requirements against customer requirements. This is followed by a number of parallel QFD 2 charts for documentation, testing, customer support, etc. Each QFD 2 chart can have corresponding QFD 3 and 4 charts as appropriate.

QFD is integrated with a full set of other tools to produce TeamSET, the most powerful suite of concurrent engineering software. It encourages the design of products that can be produced at minimum cost and maximum quality and reliability to give maximum customer satsfaction.

Benefits of using QFD

• Products meet customer expectations better
• Improved design traceability
• Reduced lead times
• Reduced product cost
• Improved communication within organisation and with customer

Problems & pitfalls

• When applying QFD do not underestimate the amount of work involved.
• Extra time and resources early in the project. Management must be prepared for this, and not press for visible results too early.
• The scope and objectives of the project must be agreed at the beginning
• Avoid trying to include too much detail. Too large a matrix results in too much data to analyse
• Best results are usually obtained by using an independent QFD facilitator to control the QFD process, leaving the rest of the team free to concentrate on the product.

Follow this link for more information on TeamSET's QFD software.