Summary of Tools for DFSS
A four-phase process
IDENTIFY(MEASURE) PHASE
The Identify phase begins the process with a formal tie of design
to Voice of the Customer. This phase involves developing a team and
team charter, gathering VOC, performing competitive analysis, and
developing CTQs.
Crucial Steps:
- Identify customer and product requirements
- Establish the business case
- Identify technical requirements (CTQ variables and spec.
limits)
- Roles and responsibilities
- Milestones
Key Tools:
- QFD (quality Function Deployment)
- FMEA (Failure Means and Effects Analysis)
- SIPOC (Supplier, Input, Product, Output, Customer product
map)
- IPDS (Integrated Product Delivery System)
- Target Costing
- Benchmarking
DESIGN (ANALYZE) PHASE
The Design phase emphasizes CTQs and consists of identifying
functional requirements, developing alternative concepts, evaluating
alternatives and selecting a best-fit concept, deploying CTQs and
predicting sigma capability.
Crucial Steps:
- Formulate concept design
- Identify potential risks using FMEA
- For each technical requirement, identify design parameters
(CTQs) using engineering analysis such as simulation
- Raw materials and procurement plan
- Manufacturing plan
- Use DOE (design of experiments) and other analysis tools to
determine CTQs and their influence on the technical requirements
(transfer functions)
Key Tools:
- Smart simple design
- Risk assessment
- FMEA
- Engineering analysis
- Materials selection software
- Simulation
- DOE
- Systems engineering
- Analysis tools
OPTIMIZE (IMPROVE) PHASE
The Optimize phase requires use of process capability information
and a statistical approach to tolerancing. Developing detailed design
elements, predicting performance, and optimizing design, take place
within this phase.
Crucial Steps:
- Assess process capabilities to achieve critical design
parameters and meet CTQ limits
- Optimize design to minimize sensitivity of CTQs to process
parameters
- Design for robust performance and reliability
- Error proofing
- Establish statistical tolerancing
- Optimize sigma and cost
- Commission and startup
Key Tools:
- Manufacturing database and flowback tools
- Design for manufacturability
- Process capability models
- Robust design
- Monte Carlo Methods
- Tolerancing
- Six Sigma tools
VALIDATE (CONTROL) PHASE
The Validate phase consists of testing and validating the design.
As increased testing using formal tools occurs, feedback of
requirements should be shared with manufacturing and sourcing, and
future manufacturing and design improvements should be noted.
Crucial Steps:
- Prototype test and validation
- Assess performance, failure modes, reliability, and risks
- Design iteration
- Final phase review
Key Tools:
- Accelerated testing
- Reliability engineering
- FMEA
- Disciplined New Product Introduction (NPI)