An Introduction to Design for Six Sigma concepts

Transcription

1 An Introduction to Design for Six Sigma concepts Dr Jane Marshall Product Excellence using 6 Sigma Module PEUSS 2012/2013 Design for Six Sigma Page 1 Objectives of the session History of Six Sigma Describe the Six Sigma Philosophy Introduce DFSS Key points in DFSS DFSS background DFSS process Differences between DFSS and Six Sigma PEUSS 2012/2013 Design for Six Sigma Page 2 1

2 Introduction to Six Sigma Six Sigma is: A business process Proactive approach to designing and monitoring key activities Philosophy Methodology A process that is customer focussed and profit driven PEUSS 2012/2013 Design for Six Sigma Page 3 Introduction to Six Sigma It works by: Being adopted by the whole company; Creating an internal infrastructure within the company; Using metrics to measure processes and changes to processes Using scientific methods, changing the working culture and introducing business process management PEUSS 2012/2013 Design for Six Sigma Page 4 2

3 Six Sigma Background Motorola employee investigating variation in various processes Acted on results using tools to reduce variation Improved the effectiveness and efficiency of the processes Engaged CEO GE is the company that made SIX Sigma a management philosophy PEUSS 2012/2013 Design for Six Sigma Page 5 What is six sigma performance? Sigma ( s ) is a statistical metric that corresponds to dpm (defectives per million) 2 s 308,537 dpm 3 s 66,807 dpm 4 s 6,210 dpm 5 s 233 dpm 6 s 3.4 dpm PEUSS 2012/2013 Design for Six Sigma Page 6 3

4 DMAIC Define Measure Analyse Improve Control Define business objectives Set Up project team, establish the charter and develop project plan Review customer requirements Map process Data collection plan Confirm starting and targets Validate measurement system Data analysis Root cause analysis Process analysis Solution generation, selection and implementation Launch new improvements Monitor controls and track defect reduction Design and implement audit plan PEUSS 2012/2013 Design for Six Sigma Page 7 Product life cycle Disposal Concept and definition Operation and maintenance Installation Continuous assessment Design and development Manufacturing PEUSS 2012/2013 Design for Six Sigma Page 8 4

5 Introduction to DFSS Systematic methodology for designing or redesigning products or services according to customer requirements and expectations. Optimises design process to achieve six sigma performance Get it right first time PEUSS 2012/2013 Design for Six Sigma Page 9 What is Design For Six Sigma? Companies who had seen the success of Six Sigma for problem solving using DMAIC wanted to apply data driven tools and techniques to the design of new products, processes & services Typically, after 2 years of DMAIC, Design For Six Sigma programmes were launched Applied in both Manufacturing and Service industries in technical and non-technical environments Used to define and/or supplement the design process PEUSS 2012/2013 Design for Six Sigma Page 10 5

6 When to Use DFSS Creating a new product, process, or service Incremental improvement cannot close the gap between the current process capability and customer requirements Should spend time understanding the faults of existing systems before you embark on a a redesign methodology PEUSS 2012/2013 Design for Six Sigma Page 11 Generic Design Process Requirements Flow down Define Project Identify Requirements Select Concept Develop Design Implement Design CTQ Flow up PEUSS 2012/2013 Design for Six Sigma Page 12 6

7 The DFSS Opportunity 1000 Classic Six Sigma focuses here Relative Cost to Impact Change DFSS focuses here 1 Research Design Development Production Product Stage Design in quality when costs are lowest PEUSS 2012/2013 Design for Six Sigma Page 13 Effect of design phases on life cycle Cost vs impact cost Potential is positive Impact>cost Potential is negative Impact<cost impact Design Produce/build deliver Service support time PEUSS 2012/2013 Design for Six Sigma Page 14 7

8 The Vision of DFSS Reactive Design Quality DFSS Predictive Design Quality From Evolving design requirements Extensive design rework Product performance assessed by build and test Performance and producibility problems fixed after product in use Quality tested in To Disciplined CTQ flow-down through requirements management Controlled design parameters Confidence in product performance Designed for robust performance and manufacture Quality designed in PEUSS 2012/2013 Design for Six Sigma Page 15 DFSS Methodology DMADV Define, Measure, Analyse, Design and Verify PIDOV Plan, Identify, Design, Optimise and Validate. PEUSS 2012/2013 Design for Six Sigma Page 16 8

9 DFSS Process Plan Identify Design Optimise Verify Develop project plans VOC CTQ Prioritise CTQ Generate, evaluate, select and review concepts Detailed design and optimise performance Demonstrate satisfies requirements Define Measure Analyze Design Verify PEUSS 2012/2013 Design for Six Sigma Page 17 Process for DFSS - DMADV Define Initiate, scope and plan the project Measure Understand customer requirements and generate specification Analyse Develop design concepts and high level design Design Develop detailed design and verification plan Verify Demonstrate compliance and launch product PEUSS 2012/2013 Design for Six Sigma Page 18 9

10 Tollgates and phases Stopping point within the flow of phases A thorough assessment of deliverables A thorough review of the project management plans for the next phase Checklists Summary statements of tools and best practices required to fulfil gate deliverable Scorecards Summary statements from specific application of tools and best practice PEUSS 2012/2013 Design for Six Sigma Page 19 DMADV Define PEUSS 2012/2013 Design for Six Sigma Page 20 10

11 DMADV - Define Develop the Charter Develop Project Plans Develop Organizational Change Plan Identify Risks Review Tollgate Requirements PEUSS 2012/2013 Design for Six Sigma Page 21 Elements of a Charter Problem Statement Opportunity Statement Importance Expectations/Deliverables Scope Schedule Team Resources PEUSS 2012/2013 Design for Six Sigma Page 22 11

12 Develop Project Plans Project schedule and milestones Organizational change plan Risk management plan Review schedule PEUSS 2012/2013 Design for Six Sigma Page 23 Risk Management Plan Design projects face a number of risks The team s job is to anticipate where the key risks of failure are and to develop a plan to address those risks In Define, the team should: Identify known and potential risks for the project Indicate when and how the risks will be addressed PEUSS 2012/2013 Design for Six Sigma Page 24 12

13 Sources of risk External legislation outwith the control of the project team Internal within control of project design, human factors and technology etc. Handle risk by taking action to avoid (mitigation) Build up reserves (contingency) PEUSS 2012/2013 Design for Six Sigma Page 25 Spheres of Risk Risks cannot be transferred between disciplines Risks must be translated between disciplines PEUSS 2012/2013 Design for Six Sigma Page 26 13

14 Project plan vs Risk plan Project Plan Outlines what the project team intend to do Supports the Project Management process Risk Plan Covers how the project team might have to change the plan Supports the Risk Management Process PEUSS 2012/2013 Design for Six Sigma Page 27 Risk Management Process Identify Quantify/Classify Analyse Get OWNERSHIP Provision Monitor Manage / Control PEUSS 2012/2013 Design for Six Sigma Page 28 14

15 Systematic Risk Identification A structured approach that allows an organised critical analysis of risks of the system under consideration. All risks are reviewed systematically. Risks are addressed from the system level to the component level. Risks arising due to system functional, environmental profiles, implicit & explicit requirements, interaction of components/subassemblies, manufacturing/assembly processes & supply chain are considered. PEUSS 2012/2013 Design for Six Sigma Page 29 Risk Categorisation Probability of occurrence high 5 Uncertainties Remain medium 3 Some uncertainties remain low 1 Few uncertainties remain Impact high 5 Major redesign and program delay medium 3 Minor redesign and schedule readjustment low 1 Requirements met within schedule Risk element scores = probability X impact PEUSS 2012/2013 Design for Six Sigma Page 30 15

16 Categorizing Risks Risks are categorized by their probability of occurrence and their impact on the project Probability of Occurrence Low Medium High Yellow Light: Proceed with caution Yellow Light: Proceed with caution Green Light: Proceed! Red Light: Address before proceeding Yellow Light: Proceed with caution Yellow Light: Proceed with caution Red Light: Do not proceed Red Light: Reassess project Red Light: Address before proceeding Low Medium High Impact on Project PEUSS 2012/2013 Design for Six Sigma Page 31 Mitigation versus Contingency Mitigation involves buying off a problem in advance Contingency means being ready to manage crises pro-actively PEUSS 2012/2013 Design for Six Sigma Page 32 16

17 Effect of mitigation and contingency on project plans Project Plan Implemented contingency becomes part of the project plan Mitigation activity is entered directly into the project plan Contingency plans and contingent mitigation plans are held in the Risk Plan Contingency Plan when an impact occurs contingency plans are moved PEUSS 2012/2013 Design for Six Sigma Page 33 Responsibility The Technical Manager or the Lead Engineer of the project He/She acts as, or alternatively, nominates a team leader. Responsible for organising Technical Risk Assessment sessions & maintaining the information and selecting a team. The team consists of at least one representative from: Project Management; Stress/Integrity; Design Engineering; Development Testing; ILS; Quality; Manufacturing; Sourcing; Systems/Requirements PEUSS 2012/2013 Design for Six Sigma Page 34 17

18 Example: Risk assessment/management process 2 RISK IDENTIFICATION Identify risk 3 RISK PRIORITISATION Assess magnitude of the risk 4 RISK MANAGEMENT Develop plans to manage the risk PEUSS 2012/2013 Design for Six Sigma Page 35 Example In order to ensure that all possible risks are identified, the risk identification for a component/sub-assembly is carried out in three stages: Brainstorm all risks associated with the FUNCTION of the component (or subassembly) Brainstorm all risks associated with the REQUIREMENT of the component (or subassembly) Brainstorm all risks associated with the MANUFACTURE/ ASSEMBLY/ SUPPLY of the component (or subassembly) PEUSS 2012/2013 Design for Six Sigma Page 36 18

19 Risk Identification Example : Brainstorming risks Subassembly Clamp Plate : The function of the clamp plate is to axially clamp the rotor windings Remember all risks brainstormed must be considered & recorded! Part Type of risk Description of risk Who Who identified the risk Rotor Wound Main Assembly PROMPTS FOR BRAINSTORMING RISKS!! Clam p Plate Function - What does it do? (eg. Insulating, protecting) Requirement - What does it have to cope with? ( eg. CF loading, vibration, temp., oil) Manufacture - How do you make this or where did you buy it (supply chain)? Clamp plate is too weak to clamp the rotor windings axially could cause windings to short against rotor framework. Cannot withstand the high CF loads could cause clamp plate to break & thus, windings to short against rotor framework New manufacturing process to be used. This may cause porosity of the material. Paul Harris Paul Harris Steve Robb PEUSS 2012/2013 Design for Six Sigma Page 37 Magnitude of risk After a risk has been identified, the next step is to assess the magnitude of the risk. This enables the prioritisation of all the risks identified & ensures that a concerted effort is made to mitigate the high scoring risks. The following factors are used to assess the magnitude of & prioritise technical risks :» Pedigree» Testing» Analysis» Severity» Probability PEUSS 2012/2013 Design for Six Sigma Page 38 19

20 No : Date: Issu e: Risk Prioritisation FACTORS USED FOR PRIORITISING RISKS PEDIGREE TESTING ANALYSIS SEVERITY PROBABILITY Do we have any past experience (product /process) that can help us assess the magnitude of the risk? Do we have any evidence from testing that can help us assess the magnitude of the risk? Do we have any evidence from theoretical analysis that can help us assess the magnitude of the risk? What impact can this risk have on the project or product? What is the likelihood of the risk being realised? Based on evidence Based on expert judgement PEUSS 2012/2013 Design for Six Sigma Page 39 Risk Prioritisation Function/Requirement Risks Pedigree 1 Identical design in Long Field Service 3 Identical design in Development Units/ Similar design in long term service 9 New Design If pedigree = 1, stop scoring, move onto next risk. Testing 1 Full representative test 3 Read across tests with good sample size/ limited tests/ Verification 9 Zero testing/ small sample size Analysis 1 Full Capable Analysis 3 Preliminary Analysis 9 No Analysis/not capable of analysis Example : Scoring Function/Requirements Risks Clamp Plate This is a new design. Therefore, Pedigree = 9 Preliminary analysis suggests design meets requirements. Therefore, Analysis = 3 Engineering Report Preliminary Analysis Report Subassembly Rotor Wound Main Assembly Part Type of risk Description of risk P T A Evidence Clamp Plate Function - What does it do? (eg. Insulating, protecting) Clamp plate is too weak to clamp the rotor windings axially Stress Report 1234 Remember to record evidence used for scoring. This can be updated as No development testing has been done using the new design of PEUSS 2012/2013 the clamp plate. Therefore, Design Testing = for 9 Six Sigma Managements actionsare completed. Page 40 20

21 Risk prioritisation severity and probability Severity 1 Low impact on product/project 3 Medium impact of product/project 9 High impact on product/project Probability 1 Low 3 Medium 9 High Example : Scoring Severity & Probability Subassembly Part Type of risk Descriptio n of risk P T A RP N1 S P R The likelihood of the risk being realised is medium. Therefore, Probability = 3 Rotor Wound Main Assembly Clam p Plate Function - What does it do? (eg. Insulating, protecting) Clamp plate is too weak to clamp If the clamp plate fails to clamp windings axially, windings centrifuge outwards & short on rotor framework, leading to catastrophic failure. Therefore, Severity = 9 Windingsshort on rotor frame work PEUSS 2012/2013 Design for Six Sigma Page 41 Risk prioritisation project risk score The Project Risk Score is calculated using the formula : Project Risk Score = S X PR The Project Risk Score is used by the project managers for the prioritisation of technical risks in the overall project risk management process. Example : Calculating the Project Risk Score Subassembl y Part Type of risk Description of risk P T A RP N1 S P R RP N2 Project Risk Score Rotor Clam Function - What Clamp plate is too Wound p does it do? (eg. weak to clamp the Main Plate Insulating, rotor windings axially. Assembl protecting) PEUSS 2012/2013 y Design for Six Sigma Page 42 21

22 Risk prioritisation managing actions Example : Managing Risk Management Actions At early stages, more risks identified, total RPN2 rises The project manager is responsible for managing the risk management actions and maintaining the risk curve. Management Action Carry out full stress analysis of clamp plate PEUSS 2012/2013 Who David Bonniema n Monitor Peter performance Dunkz of clamp Fieldsplate filled in by project when manager next five development units are tested Planne d Closure Date Actual Closure Date Status 15/01/02 Open 15/01/02 Open Expected Trend RPN2 A380 VFG Risk Curve Effective management of risks RPN 2 falls. Time Design for Six Sigma Page 43 Risk Management Identify some risks for projects Estimate the probability of occurrence Estimate the effect/impact Identify mitigating actions for highest scoring risks. PEUSS 2012/2013 Design for Six Sigma Page 44 22

23 Project Reviews Regular reviews are key for successful projects and should be included in the project schedule There are several levels of review: Milestone or tollgate reviews; weekly reviews; daily reviews In addition, design projects have three unique reviews: Concept review; High-level design review; Detailed design review PEUSS 2012/2013 Design for Six Sigma Page 45 Key Outputs of DEFINE Phase Project team Project business case Project objective Project plan (GANNT chart) Document control systems Risk reduction plan PEUSS 2012/2013 Design for Six Sigma Page 46 23

24 DMADV Measure PEUSS 2012/2013 Design for Six Sigma Page 47 DMADV - Measure Goals: Collect Voice of the Customer data Translate VOC into design requirements (CTQs) Identify the most important CTQs Develop the measurement system for each CTQ Develop a design scorecard Revise project objective if necessary Output: Prioritized CTQs PEUSS 2012/2013 Design for Six Sigma Page 48 24

25 Measure: Tools Data collection plan Customer segmentation Customer research Voice of Customer table Kano model Affinity diagram Benchmarking QFD (Quality Function Deployment) PEUSS 2012/2013 Design for Six Sigma Page 49 Measure: Key Activities Understand Voice of the Customer Translate VOC Needs Into Requirements (CTQs) Prioritize CTQs Reassess Risk PEUSS 2012/2013 Design for Six Sigma Page 50 25

26 What is the Voice of the Customer? The term Voice of the Customer (VOC) is used to describe customers needs and their perceptions of your product or service It includes all forms of interaction between customers and your organization Use of Kano analysis PEUSS 2012/2013 Design for Six Sigma Page 51 Critical to Quality Characteristics A quality characteristic that specifies how the customer need will be met by the product/service to be designed A quantitative measure for the performance of the quality characteristic A target value that represents the desired level of performance that the characteristic should meet Specification limits that define the performance limits that will be tolerated by customers Several CTQs will exist for each need. Use QFD to transfer VOC data into CTQs PEUSS 2012/2013 Design for Six Sigma Page 52 26

27 Develop and Validate a measurement system Review data requirements Review how to capture data Review applicable analysis methods e.g. compare voice of the process with voice of the customer SPC and capability analysis Decision criteria to determine acceptance Establish validity of the measurement system PEUSS 2012/2013 Design for Six Sigma Page 53 Develop a design scorecard Used to help the team to: Establish nominal values and specification limits for each CTQ Predict output of the voice of the process with respect to stability (SPC) Highlight problems and risks of CTQs Track CTQs throughout the entire life of the product PEUSS 2012/2013 Design for Six Sigma Page 54 27

28 Generic design scorecard Scorecard Part A (Voice of the customer) CTQ Target LSL USL Sigma target Scorecard Part B (Predicted Voice of the process) Stable (Y/N) Shape Mean Standard Deviation DPU Predicted Process Sigma PEUSS 2012/2013 Design for Six Sigma Page 55 Reassess Scope and Risk How difficult do we predict it will be to meet all the target values of the most important CTQs? Is it necessary to adopt a phased approach to meet the target? What are the risks associated with not meeting the CTQs now? What are the risks associated with dropping some of the less important CTQs from consideration? PEUSS 2012/2013 Design for Six Sigma Page 56 28

29 Measure: Tollgate Review This tollgate review focuses on Customer segmentation strategy Top customer needs Top 8-10 CTQs and targets Summarized benchmark information Platform management matrix CTQ achievement matrix The review can lead to the following steps: Proceed to Analyse Redo parts Measure Stop the project PEUSS 2012/2013 Design for Six Sigma Page 57 DMADV Analyse PEUSS 2012/2013 Design for Six Sigma Page 58 29

30 DMADV - Analyse: Key questions Important processes/functions that must be designed to meet the design requirements? Key inputs and outputs of each process? Processes for which innovative new designs are required to maintain a competitive advantage? Different solutions available for designing each process? What criteria do we use to evaluate these design alternatives? Collect information on these criteria for evaluation? PEUSS 2012/2013 Design for Six Sigma Page 59 DMADV - Analyse Identify Key Functions Prioritize Functions Generate Concepts Evaluate and Analyze Concept Review PEUSS 2012/2013 Design for Six Sigma Page 60 30

31 Identify Key Functions PEUSS 2012/2013 Design for Six Sigma Page 61 Identify Key Functions PEUSS 2012/2013 Design for Six Sigma Page 62 31

32 Generate Concepts Concepts are generated using two approaches: Creative idea-generation techniques that focus on analogy, connections, extrapolations and creative visualization to develop new ideas Benchmarking techniques that study similar designs in competing and non-competing businesses PEUSS 2012/2013 Design for Six Sigma Page 63 Design Review Process for objectively evaluating the quality of a design at various stages of the design process Opportunity for voices external to the design team to provide feedback on the design, as the product and service is being developed Helps to ensure that the design will satisfy customers, and that the design process will function effectively to produce a high quality product or service PEUSS 2012/2013 Design for Six Sigma Page 64 32

33 When to conduct a design review Concept Review: Conducted after two to three key concepts have been identified and their feasibility has been determined. High Level Design Review: Conducted after a selected concept has been designed to some level of detail and tested, and before detailed design begins. Pre-pilot Design Review: Conducted when the detailed design is complete and the product/service is ready to be piloted. PEUSS 2012/2013 Design for Six Sigma Page 65 Design for X Design for manufacture Design for assembly Design for reliability Design for testability Design for service Design for quality Design for reusability Design for environment PEUSS 2012/2013 Design for Six Sigma Page 66 33

34 Analyse: Tollgate Review This tollgate review focuses on: List of key functions List of top concepts Pugh Matrix Concept review outputs Risk analysis update This review can lead to the following steps: Proceed to High Level Design Redo work on concepts, concept review and tollgate review Stop the project PEUSS 2012/2013 Design for Six Sigma Page 67 DMADV Design PEUSS 2012/2013 Design for Six Sigma Page 68 34

35 DMADV - Design High Level Design Detailed Design PEUSS 2012/2013 Design for Six Sigma Page 69 From Concept to Design Less Detail /Many Alternatives CONCEPT DESIGN More Detail/Few Alternatives HIGH LEVEL DESIGN Redesign Most Detail/Single Alternative DETAILED DESIGN PEUSS 2012/2013 Design for Six Sigma Page 70 35

36 Design: Goals and Outputs Goals: Develop high level and detailed design Test design components Prepare for pilot and full scale deployment Outputs: Tested high level design Tested detailed design Plans for process control Completed design reviews PEUSS 2012/2013 Design for Six Sigma Page 71 Design: Tools QFD Simulation Rapid prototyping Weibull analysis SPC and process capability Detailed design scorecards FMEA Reliability testing and qualification testing Design reviews PEUSS 2012/2013 Design for Six Sigma Page 72 36

37 Tollgate review The pre-pilot detailed design tollgate review focuses on: Developed design Completed FMEA/simulation analysis Design solutions for vulnerable elements Organizational Change Plan updates Process management system variables Process management system details PEUSS 2012/2013 Design for Six Sigma Page 73 DMADV Verify PEUSS 2012/2013 Design for Six Sigma Page 74 37

38 DMADV - Verify Plan the Pilot Conduct and Evaluate the Pilot Implement Close Project PEUSS 2012/2013 Design for Six Sigma Page 75 Steps in the Verify phase Build a prototype Pilot test the prototype conduct design reviews using design scorecards Decide if the process is meeting business objectives Close DMADV project Transfer lessons learned from the project PEUSS 2012/2013 Design for Six Sigma Page 76 38

39 Verify: Goals and Outputs Goals: Stress-testing and de-bugging of prototype Implementation and team closure Outputs: Working prototype with documentation Plans for full implementation Process owners using control plans to measure, monitor and maintain process capability Project closure and documentation completed Ownership transition from sponsor to operations management, and from design team to process management team(s) Lessons learned PEUSS 2012/2013 Design for Six Sigma Page 77 Completion Checklist Completed project documentation that summarizes results and learnings Recommendations (supported by updated information, if possible) for the next generation of this design Plans for (or results from) communicating your achievements to the rest of the organization Plans for celebrating your success PEUSS 2012/2013 Design for Six Sigma Page 78 39

40 Advantages of DFSS Provide structure to development process Anticipate problems and avoid them Reduce life cycle cost Improve product quality, reliability and durability Cultural change Minimise design changes Improve communication between functions PEUSS 2012/2013 Design for Six Sigma Page 79 Difference between SS and DFSS DMAIC reactionary detecting and resolving problems Existing products or services Financial benefits quantified quickly Mainly manufacturing processes DFSS proactive preventing problems Design of new products, services or processes; Financial benefits long-term Marketing R&D and design DFSS team cross-functional PEUSS 2012/2013 Design for Six Sigma Page 80 40

41 DFSS Summary Rigorous approach to design Primarily used for new product design Structured approach DMADV and PIDOV Tailored for each company In conjunction with product introduction Pushes key issues up front design for reliability and design for manufacture PEUSS 2012/2013 Design for Six Sigma Page 81 41