Quality Function Deployment

Quality Function Deployment

•Introduction Quality Function Deployment•Definition & Characters of QFD•Tools of QFD•House of Quality & Quality Charts•Case Study • Applications & Advantages

QFD – Basic Definition & Need

Integrating customer requirements into product designQuality: Meeting the specifications & satisfying customersFunction: Action that forms quality & satisfies the needsDeployment: Step-by-step incorporation of that Action

Users and customers of products or services usually have fairly good ideas as to what they expect:

A car should not rust, should start in all weather conditions, should be economically on petrol, be versatile in the arrangements of seats, etc. – Until the QFD principles were developed, it was fairly normal that new products would be developed after the likes, dislikes and technical ideas of the developers, with not enough attention paid to the production process, servicing and last but not least to the real expectations of the customers. – A famous example is the Ford “Edsel” model of the 1950s, of which only a few 100 were sold, contrary to the millions which had been anticipated.

Introduction to QFD QFD is a comprehensive quality system that

systematically links the needs of the customer with various business functions and organizational processes, such as marketing, design, quality, production, manufacturing, sales, etc., aligning the entire company toward achieving a common goal.

A method to transform user demands into design quality, 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.

Dr. Yoji Akao originally developed QFD in Japan in 1966, when the he combined his work in quality assurance and quality control with function deployment used in value engineering.

QFD provides a system of comprehensive development process for: Understanding 'true' customer needs from the

customer's perspective What 'value' means to the customer, from the

customer's perspective Understanding how customers or end users become

interested, choose, and are satisfied Analyzing how do we know the needs of the customer Deciding what features to include Determining what level of performance to deliver Intelligently linking the needs of the customer with

design, development, engineering, manufacturing, and service functions

Intelligently linking Design for Six Sigma (DFSS) with the front end Voice of Customer analysis and the entire design system

WHAT DOES QFD DO? Better Designs in Half the Time

QFD is a Productivity Enhancer

Why Does QFD Work?

PROCESSDESIGN PRODUCTION

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LOW VISIBILITYLOW REWARD

The Quality LeverThe Quality Lever

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Tools of QFD•Affinity Diagrams•Relation Diagrams•Matrices and Tables – House of QualityI. Prioritization, Relationship, Responsibility Matrices•Analytical Hierarchy Process•Hierarchy Trees•Production Design Program Diagrams•Blueprinting

QFD

STATISTICALPROCESS CONTROL

DESIGN QUALITY

VALUEENGINEERING

The Houseof Quality

Quality Function Deployment’sHouse of Quality

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Customer Wants

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Building the House of Quality1. Identify Customer Attributes – What’s2. Identify Design Attributes / Requirements –

How’s3. Relate the customer attributes to the design

attributes.4. Conduct an Evaluation of Competing Products.5. Evaluate Design Attributes and Develop

Targets.6. Determine which Design Attributes to Deploy in

the Remainder of the Process.

1. Identify Customer Attributes• These are product or service requirements IN THE

CUSTOMER’S TERMS. • Market Research• Surveys• Focus Groups.

• “What does the customer expect from the product?”

• “Why does the customer buy the product?”• Salespeople and Technicians can be important

sources of information – both in terms of these two questions and in terms of product failure and repair.

• OFTEN THESE ARE EXPANDED INTO Secondary and Tertiary Needs / Requirements.

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Customer Ranking of their Needs

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2. Identify Design Attributes.

• Design Attributes are Expressed in the Language of the Designer / Engineer and Represent the TECHNICAL Characteristics (Attributes) that must be Deployed throughout the DESIGN, MANUFACTURING, and SERVICE PROCESSES.

• These must be MEASURABLE since the Output will be Controlled and Compared to Objective Targets.

• The ROOF of the HOUSE OF QUALITY shows, symbolically, the Interrelationships between Design Attributes.

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Product Requirements Translation For Action X’s

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WHAT'S HOW'S

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Impact Of The How’s On Each Other

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Correlation MatrixCorrelation Matrix

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3.Relating Customer & Design Attributes Symbolically we determine whether there is NO

relationship, a WEAK one, MODERATE one, or STRONG relationship between each Customer Attribute and each Design Attribute.

The PURPOSE it to determine whether the final Design Attributes adequately cover Customer Attributes.

LACK of a strong relationship between A customer attribute and any design attribute shows that the attribute is not adequately addressed or that the final product will have difficulty in meeting the expressed customer need.

Similarly, if a design attribute DOES NOT affect any customer attribute, then it may be redundant or the designers may have missed some important customer attribute.

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Untangling The WebUntangling The Web

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5. Evaluate Design Attributes of Competitive Products & Set Targets.

This is USUALLY accomplished through in-house testing and then translated into MEASURABLE TERMS.

The evaluations are compared with the competitive evaluation of customer attributes to determine inconsistency between customer evaluations and technical evaluations.

For example, if a competing product is found to best satisfy a customer attribute, but the evaluation of the related design attribute indicates otherwise, then EITHER the measures used are faulty, OR else the product has an image difference that is affecting customer perceptions.

On the basis of customer importance ratings and existing product strengths and weaknesses, TARGETS and DIRECTIONS for each design attribute are set.

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Target Values for the How’s

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Ranking The HOW'SRanking The HOW'S

Which How’s are Key Where Should The Focus Lie “CI” = “Customer Importance” “Strength” is measured on a 9, 3, 1,

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Using the House of Quality

The voice of the customer MUST be carried THROUGHOUT the production process.

Three other “houses of quality” are used to do this and, together with the first, these carry the customer’s voice from its initial expression, through design attributes, on to component attributes, to process operations, and eventually to a quality control and improvement plans.

In Japan, all four are used.

The tendency in the West is to use only the first one or two.

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The How’s at One Level Become the What’s at the Next Level

The How’s at One Level Become the What’s at the Next Level

Deployment Through the Levels of Product Development

Weighing importance of each Customer Requirement

QFD relationship and rank of attributes

Advantages During the last 2 decades, in large parts of the manufacturing industry (automotive, electronics etc) the quality function deployment (QFD) technique has been applied to the development, manufacturing and servicing of products. Quantum leap improvements of more than a factor of 2 have been achieved with respect to:• reduction of development times• “painless” transition from development to production (in terms of necessary changesto make the product fit for production)• time for production ramp up• service and user friendliness (measured for instance by the number of customer complaints and emergency actions like call back of cars from the consumers)

Kano Customer Need Model

Dissatisfiers Those needs that are EXPECTED in a product or service. These are generally not stated by customers but are assumed as given. If they are not present, the customer is dissatisfied.

Satisfiers Needs that customers SAY THEY WANT. Fulfilling these needs creates satisfaction.

Exciters /Delighters

New or Innovative features that customers do not expect. The presence of such unexpected features leads to high perceptions of quality.

Kano Model

GARVIN’S EIGHT DIMENSIONS OF PRODUCT QUALITY

Performance FeaturesConformanceAesthetics

ReliabilityDurabilityServiceabilityPerceived

Quality

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