QUALITY FUNCTION DEPLOYMENT

QUALITY FUNCTION DEPLOYMENT (QFD)

Introduction

            Quality Function Deployment (QFD) is a structured approach to defining customer needs or requirements and translating them into specific plans to produce products to meet those requirements. The "voice of the customer" is the term to describe these stated and unstated customer needs or requirements. The voice of the customer is captured in a variety of ways: direct discussion, surveys, customer specifications, observation, warranty data, field reports, etc. This understanding of the customer requirements is then summarized in a product planning matrix or "house of quality". These matrices are used to translate higher level "what's" or requirements into lower level "how's" or means to satisfy the requirements.

            While the QFD matrices are a good communication tool at each step in the process, the matrices are the means and not the end. The real value is in the process of communicating and decision-making with QFD. QFD is oriented toward involving a team of people representing the various functional departments that have involvement in product development: Marketing, Design Engineering, Quality Assurance, Manufacturing/ Manufacturing Engineering, Test Engineering, Finance, Product Support, etc.

            The active involvement of these departments can lead to balanced consideration of the requirements or "what's" at each stage of this translation process and provide a mechanism to communicate hidden knowledge - knowledge that is known by one individual or department but may not otherwise be communicated through the organization. The structure of this methodology helps development personnel understand essential requirements, internal capabilities, and constraints and design the product so that everything is in place to achieve the desired outcome - a satisfied customer. QFD helps development personnel maintain a correct focus on true requirements and minimizes misinterpreting customer needs. As a result, QFD is an effective communications and a quality planning tool.

            Yoji Akao developed QFD during the late 1960s in Japan. It was first applied atMitsubishi Kobe Shipyards in 1972 to assure customer satisfaction. Masao Kogure andYoji Akao introduced QFD to the USA in the article "Quality function deployment and CWQC in Japan" which appeared in Quality Progress in October issue of 1983. QFD is a structured approach to seek out customers and understand their needs. It begins by matching customer requirement, which on turn match with necessary corresponding production requirement, and so on, to ensure that the needs of the customer met. If done right QFD is likely to be one contributing factor to product or service success [Griffinand Hauser, 19931. When products designed to meet or exceed customer needs, the sales goes up.

            In using the QFD, organizations will be able to achieve reduction on the number of design changes, lower startup cost, and shorter design cycles, fewer warranty claims, improved the internal communications and increased sales. Another key benefit of QFD is that engineering knowledge is retained in systematic manner so that it can be easily applied. to future similar designs. QFD also helps to identify specific, competitive advantages and create the opportunity to supply niche product. The whole QFD procedure uses a series of matrices called house to express the linkage between inputs and outputs of different phases of development. [Christian N, 2006]

The 3 main goals in implementing QFD are:

1. Prioritize spoken and unspoken customer wants and needs.

2. Translate these needs into technical characteristics and specifications.

3. Build and deliver a quality product or service by focusing everybody toward customer satisfaction.

Principle of QFD

            QFD uses some principles from Concurrent Engineering in that cross-functional teams are involved in all phases of product development. Each of the four phases in a QFD process uses a matrix to translate customer requirements from initial planning stages through production control (Becker Associates Inc, 2000). Each phase, or matrix, represents a more specific aspect of the product's requirements. Relationships between elements are evaluated for each phase. Only the most important aspects from each phase are deployed into the next matrix.

1) Phase 1, Product Planning: 
 Building the House of Quality. Led by the marketing department, Phase 1, or product planning, is also called The House of Quality. Many organizations only get through this phase of a QFD process. Phase 1 documents customer requirements, warranty data, competitive opportunities, product measurements, competing product measures, and the technical ability of the organization to meet each customer requirement. Getting good data from the customer in Phase 1 is critical to the success of the entire QFD process.

2) Phase 2, Product Design:  
This phase 2 is led by the engineering department.

Product design requires creativity and innovative team ideas. Product concepts are created during this phase and part specifications are documented. Parts that are determined to be most important to meeting customer needs are then deployed into process planning, or Phase 3.

3) Phase 3, Process Planning: 
 Process planning comes next and is led by manufacturing engineering. During process planning, manufacturing processes are flow-charted and process parameters (or target values) are documented.

4) Phase 4, Process Control:  
And finally, in production planning, performance indicators are created to monitor the production process, maintenance schedules, and skills training for operators. Also, in this phase decisions are made as to which process poses the most risk and controls are put in place to prevent failures. The quality assurance department in concert with manufacturing leads Phase 4.

House of Quality

House of Quality (Shaw & Ebrahimpour 2000)

Step To Do the House of Quality

Step 1: Customer Requirements - "Voice of the Customer"

The first step in a QFD project is to determine what market segments will be analyzed during the process and to identify who the customers are. The team then gathers information from customers on the requirements they have for the product or service. In order to organize and evaluate this data, the team uses simple quality tools like Affinity Diagrams or Tree Diagrams.

Step 2: Regulatory Requirements

Not all product or service requirements are known to the customer, so the team must document requirements that are dictated by management or regulatory standards that the product must adhere to.

Step 3: Customer Importance Ratings

On a scale from 1 - 5, customers then rate the importance of each requirement. This number will be used later in the relationship matrix.

 

Step 4: Customer Rating of the Competition

Understanding how customers rate the competition can be a tremendous competitive advantage. In this step of the QFD process, it is also a good idea to ask customers how your product or service rates in relation to the competition. There is remodeling that can take place in this part of the House of Quality. Additional rooms that identify sales opportunities, goals for continuous improvement, customer complaints, etc., can be added.

Step 5: Technical Descriptors - "Voice of the Engineer"

The technical descriptors are attributes about the product or service that can be measured and benchmarked against the competition. Technical descriptors may exist that your organization is already using to determine product specification, however new measurements can be created to ensure that your product is meeting customer needs.

Step 6: Direction of Improvement

As the team defines the technical descriptors, a determination must be made as to the direction of movement for each descriptor.

Step 7: Relationship Matrix

The relationship matrix is where the team determines the relationship between customers’ needs and the company's ability to meet those needs. The team asks the question, "What is the strength of the relationship between the technical descriptors and the customers’ needs?" Relationships can either be weak, moderate, or strong or carry a numeric value of 1, 3 or 9.

Step 8: Organizational Difficulty

Rate the design attributes in terms of organizational difficulty. It is very possible that some attributes are in direct conflict. Increasing the number of sizes may be in conflict with the company's stock holding policies, for example.

Step 9: Technical Analysis of Competitor Products

To better understand the competition, engineering then conducts a comparison of competitor technical descriptors. This process involves reverse engineering competitor products to determine specific values for competitor technical descriptors.

Step 10: Target Values for Technical Descriptors

At this stage in the process, the QFD team begins to establish target values for each technical descriptor. Target values represent "how much" for the technical descriptors, and can then act as a base-line to compare against.

Step 11: Correlation Matrix

This room in the matrix is where the term House of Quality comes from because it makes the matrix look like a house with a roof. The correlation matrix is probably the least used room in the House of Quality; however, this room is a big help to the design engineers in the next phase of a comprehensive QFD project. Team members must examine how each of the technical descriptors impacts each other. The team should document strong negative relationships between technical descriptors and work to eliminate physical contradictions.

Step 12: Absolute Importance

Finally, the team calculates the absolute importance for each technical descriptor. This numerical calculation is the product of the cell value and the customer importance rating.

Numbers are then added up in their respective columns to determine the importance for each technical descriptor. Now you know which technical aspects of your product matters the most to your customer!

Conclusion

            QFD is a systematic means of ensuring that customer requirements are accurately translated into relevant technical descriptors throughout each stage of product development. Therefore, meeting or exceeding customer demands means more than just maintaining or improving product performance. It means designing and manufacturing products that delight customers and fulfill their unarticulated desires. Companies growing into the 21st century will be enterprises that foster the needed innovation to create new markets.