설계단계에서의 품질향상 : Quality Function Deployment (QFD) #10 & #11

QFD 의 개관

IE, POSTECH Quality Engineering Lab. Missing Link

IE, POSTECH Quality Engineering Lab. Historical Evolution of Quality Practices 1980's 1940's 1920's Product Design Process Design Manufacturing Inspection Process Control Quality by Design Product Development Stages

IE, POSTECH Quality Engineering Lab. Quality Lever Product Design Process Design Production Improve Product 100:1 10:1 1:1 PAYOFFS

IE, POSTECH Quality Engineering Lab. Tools for Quality Improvement

IE, POSTECH Quality Engineering Lab. QFD: Concept...We may think of Quality Function Deployment as representing a shift from Traditional Manufacturing Quality Control upstream to Product Design Quality Control.

IE, POSTECH Quality Engineering Lab. QFD: Definition Translate customer requirements into the technical requirements for product development and production: – Planning – Product design and engineering – Prototype development – Production – Sales Customer Driven Product Development

IE, POSTECH Quality Engineering Lab. Japanese / U.S. Engineering Change Comparison

IE, POSTECH Quality Engineering Lab. Comparison of Old and New Design System

IE, POSTECH Quality Engineering Lab. QFD: Goals / Advantages Product-Related Improvements – Improved design reliability – Fewer startup problems – Warranty claim reduction Process-Related Improvements – Shorter product development cycle / lead time – Lower cost to commercialization – Intangible benefits Increase in the Market Share

IE, POSTECH Quality Engineering Lab. QFD: History Created in the late 1960's Mitsubishi's Kobe Shipyard Site (1972) Toyota (since mid 1970's) Ford (since 1985) US-based Companies (since mid 1980's) – More than 100 firms including: General Motors, Budd, Kelsey Hayes, Motorola, DEC, Hewlett-Packard, Xerox, AT&T, ITT, NASA, Goodyear, Kodak Eastman, NCR, Procter & Gamble,... – Annual QFD symposium since 1989

QFD: Applications in 1990’s QFD Applications Presented at Annual QFD Symposium

IE, POSTECH Quality Engineering Lab. QFD: Applications in 1990’s (continued) Manufacturing Automotive, Electronics, Computer, Aerospace, etc. Service Healthcare, Education, Hotel, Telecommunications, Energy, etc. Administration Strategic planning, Organization/Process Reengineering, Human resource management, Marketing, Auditing, etc. Others Software design, Information systems, Military, Construction industry, Environment, etc.

IE, POSTECH Quality Engineering Lab. QFD: Basic Idea Translation Rust Study Customer Attributes Rust Resistant Engineering Characteristics No Visible Exterior Rust in 3 Years Parts' Characteristics Paint Wt: gm/m2 Crystal Size: 3 max Process Planning Dip Tank 3 coats Production Requirements Time: 2.0 minutes min. Acidity: Temp: C

IE, POSTECH Quality Engineering Lab. Translation of Customer Requirements

House of Quality 의 작성

IE, POSTECH Quality Engineering Lab. House of Quality Conceptual Map that Provides the Means for Interfunctional Planning and Communication. Used as a Tool for Communication and Decision Making. Contains Information on –Customer Attributes (CA’s) and Their Relative Importance. –Current Perceptions of Customer Attributes (Company’s and Competitor’s Products). –Engineering Characteristics (EC’s), How They Affect Customer Attribute Levels as Well as Each Other. –Current Measures of Engineering Characteristic Levels (Company’s and Competitors’ Products).

IE, POSTECH Quality Engineering Lab. House of Quality: Examples of CA’s and EC’s Customer Attributes (CA’s) –Ease of Service, Ease of Repair, Amount of “Rattle”, Amount of Water Leakage. –Are Typically Qualitative in Nature. –Can Typically be Arranged in a Hierarchy. Engineering Characteristics (EC’s) –Force Required to Close Door, Gap Between Body and Door, Width of Window Strip. –Are Typically Quantitative in Nature. –Can Typically Be Arranged in a Hierarchy.

IE, POSTECH Quality Engineering Lab. House of Quality: Schematic

House of Quality: Video Game

IE, POSTECH Quality Engineering Lab. HOQ 작성 Guideline (1)

IE, POSTECH Quality Engineering Lab. HOQ 작성 Guideline (2)

IE, POSTECH Quality Engineering Lab. House of Quality: MOFA FUSE Example

IE, POSTECH Quality Engineering Lab. House of Quality: Air Conditioning Control Device (Eaton)

IE, POSTECH Quality Engineering Lab. House of Quality: Car Door Example

QFD 사례 실습

IE, POSTECH Quality Engineering Lab. QFD 사례 실습 사례 실습 목표 대상 주제에 대해 HOQ 를 구성하고 이를 분석하는 과정을 통하여, QFD 의 개념과 진행 과정에 대한 이해를 심화한다. 팀 구성 전공 분야가 같지 않은 3 명 내외가 한 팀을 이룬다. 사례 주제 선정 팀원의 토의를 거쳐 팀별로 하나의 주제를 선정한다. 편의상 9 개의 주제 후보가 아래에 예시되어 있다. - 제품 : 안경, 휴대전화, diary/ 전자수첩, 면도기, 라이터, 시계 - 서비스 : 은행, 병원, 전자상거래

IE, POSTECH Quality Engineering Lab. QFD 사례 실습 ( 계속 ) HOQ 크기 요구 조건 - CA 는 다단계의 계층구조로 이루어졌을 때 최하위 단계의 요구사항이 8~10 개 정도, EC 는 10 ~ 15 개 정도로 한다. (HOQ 크기에 대한 요구조건은 사례 연구의 일정과 인원 등을 고려하여 너무 복잡해지지 않도록 설정한 것이므로, 필요에 따라 조정할 수 있다.) - Benchmarking 을 위해 적어도 3 개의 제품 / 서비스를 비교하되, 그 중 임의로 선택한 1 개를 자사의 제품 / 서비스로, 그리고 나머지를 타사의 제품 / 서비스로 간주한다. CA 및 EC 항목의 설정 - CA : 소비자 입장 - EC : 설계자 / 개발자 입장

IE, POSTECH Quality Engineering Lab. QFD 사례 실습 ( 계속 ) Relationship & Correlation Matrix 의 작성 - Cross-Functional Team 의 역할 분담 ( 예 : 기획, 마케팅, 설계, 생산 등 ) Teamwork - Brainstorming - 팀원 간의 의견 차이 확인 및 상호존중 - 합의 (Consensus) 도출 시도 Software 의 활용 - VOC 의 평가 과정에서는 Expert Choice, HOQ 의 작성 과정에서는 QFD Designer 등의 Software 를 활용할 수 있다.

House of Quality: Worksheet

QFD 관련 참고문헌

IE, POSTECH Quality Engineering Lab. QFD 관련 참고문헌 Hauser, J. R. and Clausing, D. “The House of Quality,” Harvard Business Review, Vol. 66, 1988, pp 김광재, "QFD 를 통한 설계단계에서의 품질 향상," IE 매거진, 2 권 1 호, 1995 년 3 월, pp Kim, K. and Moskowitz, H., "Quality Function Deployment: Optimizing Product/Process Design,” Integrated Product, Process and Enterprise Design (Ed. Ben Wang), Chapman & Hall, London, 1997, pp Kim, K., “Quality Function Deployment: Basic Mechanism,” IE671 Class Notes, POSTECH. 포항공과대학교 산업공학과 품질공학연구실 홈페이지 (