Quality Function Development (QFD) In 1966 Dr.Yoji Akao developed QFD in Japan and defined it as "method wily to transform qualitative user demands into quantitative parameters, to deploy the functions forming quality, and to deploy methods for achieving the design quality into subsystems and component parts, and ultimately to specific elements of the manufacturing process." Akao, Yoji (1994). QFD is developed to help planners to concentrate on characteristics of a new or existing product or service from the viewpoints of market segments, company, or technology development needs. The technique yields charts and matrices. QFD aims at translating customer needs (the voice of the customer) into engineering characteristics for a product or service, prioritizing each product or service characteristic while simultaneously setting development targets for product or service. So we can say that QFD is a customer- oriented approach to product innovation and provides product managers and design teams with road map to develop products on a structured way that relates customer needs by engineering specifications to parts specifications and to production process variables and thus to production operations planning. QFD is derived from the Japanese concept of "Company Wide Quality Control" (CWQC) which is customer oriented and is characterized by cross functional management and process rather than product orientation and translating customer needs for all stages of product development and production (i.e. marketing strategies, design, planning, process development, production control). So as in project management rules, project should be defended, team should be selected and it should not be restricted to a single action within just one department. Teams should be cross-functional, expertise oriented and consisting of six to eight members of comparable peer levels. QFD can be summarized by a step by step approach marking the points at which the requirements for intermediate results are established and go-or-no go decisions can be made. Usually we can discern four phases: In the strategy phase, product policy and target customers will be determined and the customer needs are translated into a product concept. The design requirements (WHAT's) act as input to establish the component characteristics (HOW's) of the product design which define the process plans and next the manufacturing process operations. Due to the complex relationships between the inputs and outputs, these relationships are mapped into matrices. The basic structure can be described in the relationship matrix of Fig. 2. For the What's How's relationships: Each How is appraised to set target goals or values, the How-Much's we want to achieve. These How-Much's should be measurable as much as possible. This method is flexible so any other information can be added to help the decision making. The product development process can be outlined using QFD charts and described as four charts (Fig. 3) and during all steps the main target is to define the right product for the right customer. The most critical part of the process is this first step and it usually is the most difficult one because it requires determining and expressing what the customer wants and not what we think he expects. The greatest goals of QFD will be understood when the "voice of the customer" is deployed to the most detailed level of manufacturing operations. This means applying all phases although it is possible to achieve substantial benefits by implementing QFD only in the first phase. QFD methodology: "The House of Quality" Before starting commitment should be done on issues like: The product or product characteristics that we are going to focus on The targeted customers The competing products that can be used as a reference for our product evaluation How does the QFD approach fit into product and process planning? Step 2 focuses on the kind of customer to be targeted. For consumer products a well defined customer profile is needed that includes the end-users and it also includes profiles of persons or interest-groups who affect the purchase decisions, e.g., retailers, consumers' associations or public authorities (environmental regulations!). Customer requirements (step 3) are collected through various data collection methods. Discrimination should be made between expressed requirements and implicit requirements while asking consumers about their requirements. The Kano model relates customer satisfaction to the degree to which product features (or requirements) are achieved (see Fig. 5). Akao, Y., 1990. The straight line represents performance features. Customers will be more satisfied if the performance exceeds their expectations and dissatisfied if they fall short. Generally, only these (mostly one-dimensional) requirements will be expressed by customers when they asked for. The implicit features are fallen into two groups: basic and excitement features. The basic features are expected and include the fundamental functions that must be present along with safety and reliability considerations. Even if all of the basic features are satisfied perfectly we would not achieve real customer satisfaction - we would only eliminate dissatisfaction. The top curve represents the excitement features which the customers perceive as superior value. Focus on the excitement features as sales points can result in a major competitive opportunity. The "voice of the customer" needs to be respected and to be considered in order to gain a collective understanding. Using a function tree the main requirement can be detailed into two or more levels (Fig. 6) to describe the "WHAT's" for the first QFD - chart. The list of "WHAT's" should be detailed enough to project the importance of each item to the targeted customers on whom we focus. The relative importance of the various requirements can be rated depending on the target group. This can be done using a scale from 1 (not very important) to 5 (very important) (step 4 see Fig. 7). It is necessary to consider developing tailored product types in the case of obvious rating differences between the target groups. (in Fig. 7, for example, a device for "sound freaks" or for "entertainment". It is of a very strategic importance to know how the competing products match up to the customer requirements compared with our own product because customers choose between products of different brands. Competitive benchmarking (step 5) answers the question "WHY" we should concentrate and focus on which requirements and will allow a plan to be derived for improvement. This comparison is shown in Fig. 8. The generation of the design parameters: the "'HOW's'" list is the core of the QFD methodology in the first phase. The design requirements result from the translation of customer dreams and wishes into technical specifications (step 6). This list must be depending on the available expertise and the given time and cost frames of the project. Symbols and/or an importance rating can be used to describe the strength of the relationship between the What's and How's and to prioritize efforts and making tradeoff- decisions. Some commonly used symbols and weighing factors are shown in Fig. 9. The 9-3-1 weighing often achieves a good spread between important and less important items,(any other weighing system which makes sense, can be used) From an organizational point of view, the design parameters refer to concrete observable characteristics and methods of measurement (see Fig. 10). It may be helpful to arrange the characteristics under headings like: mechanical, electrical, software, etc. The design parameters have to reflect and represent a valid measurement of customer requirements. There is no one-to-one relationship and the interactions vary in intensity. The weighing and completion of the relation matrix (step 7) translate the project objectives into a technical priority list. This also gives us the chance to cross-check our thinking. Blank rows or blank columns highlight places where our translation of What's into How's has been insufficient! The operationalisations of How's are the HOW MUCH's. The How Much's should be descriptive and should be measurable as much as possible. If How Much's are non descriptive or not measurable, so the definition of the How's is not detailed enough (another cross check of our thinking!) HOW MUCH's are needed for the following reasons: To provide opportunities, priorities and directions for improvements of the How's (an extra row can indicate this and is added to the How-Much mapping. To provide an objective tools for assuring that requirements have been satisfied. To provide targets for the next future development(step 8) For setting the targets, a competitor's analysis on technical data should be performed. The benchmarking on technical performance (step 9) sets our technical position with respect to the other competitors. This type of benchmarking provides a test for consistency of the relation matrix (step7) and the competitive benchmarking data (step 5). For example, the higher the score for customer requirement X the higher the scores for design parameters which are strongly related with that requirement. Mostly interdependency will be found between the design parameters. In the top of the house supporting and conflicting design parameters are identified by a correlation matrix (step 10). Different degrees of interaction will be represented again by symbols. (See Fig. 11). The sign of correlations (positive or negative) are based on the effect of How's on achieving other How's regardless of the direction in which the How Much values move. Positive correlations result from one How supports another. On the other hand, negative correlations result from one How reverses the achievement of another Flow. These conflicts are very important as they represent conditions to direct trade-offs. There are many useful extensions to the basic QFD charts that strongly enhance their usefulness [Akao, Y., 1990 & King, R., 1989.]. These give some additional methodology to help in the decision process. For example, in the figures we made use of symbols. Importance rating method is a widely used method. For each cell, a relative weight can be calculated by multiplying the ratings of the What's and the assigned weights to each relationship matrix symbol. Summing the weights for each column provides a relative importance of each How in achieving the collective What's (see Fig. 12). Care must be taken that we are not blindly driven by these numbers. These values have no direct meaning but rather must be interpreted and translated by comparing the magnitudes to each other. The relative values of the numbers in light of our judgment. The How valued at 90 is about ten times as important as the How valued at 9 and the Howls with similar ratings are nearly equal in importance. If this judgment is violated, the chart should be reviewed for possible errors. According to the importance rating, a trade-off decision is necessary between the How's with the 90 and 9 ratings; greater focus should be placed on the How with the 90 rating. When the first phase has been completed, the following goals have been achieved: Customer needs and their importance. A competitive assessment of our product. The relationships between customer needs and design parameters. Priorities for development and improvement based on a cross functional approach. Ways to facilitate communication and to ensure that the objective values and trade-off decisions are not "lost" and support the company's learning process. As already mentioned, in the next phase, the design requirements (HOW's) are carried on as WHAT's to the next chart to establish product or part characteristics. This is continued to define the process characteristics and subsequently manufacturing operations. References: provide targets for further detailed development Akao, Y., 1990. Quality Function Deployment, Integrating Customer Requirements into Product Design. Productivity Press. Cambridge, MA. Akao, Yoji (1994). "Development History of Quality Function Deployment". The Customer Driven Approach to Quality Planning and Deployment. Minato, Tokyo 107 Japan: Asian Productivity Organization. p. 339. ISBN 9283311213. King, R., 1989. Better Designs in Half the Time. Implementing Quality Function in America. 3rd ed. Goal QPC, Methuen. MA.