Design for Six Sigma by Peter Peterka
Design for Six Sigma (DFSS) is the application of Six Sigma
principles to the design of products and their manufacturing and
support processes. Whereas Six Sigma by definition focuses on
the production phase of a product, DFSS focuses on research,
design, and development phases. DFSS combines many of the tools
that are used to improve existing products or services and
integrates the voice of the customer and simulation methods to
predict new process and product performance.
DFSS can be compared to DMAIC (Design, Measure, Analyze,
Improve, Control) and often the acronym DMADV (Define, Measure,
Analyze, Design, Verify) is used to describe the strategy of
DFSS. The precise phases or steps of a DFSS methodology are not
universally defined. Most organizations will implement DFSS to
suit their business, industry, and culture. DFSS methodology,
instead of the DMAIC methodology, should be used when: * A
product or process is not in existence at your company and one
needs to be developed * The existing product or process exists
and has been optimized (using either DMAIC or not) and still
doesn't meet the level of customer specification or six sigma
level DFSS is a way to implement the Six Sigma methodology as
early in the product or service life cycle as possible. It is a
strategy toward extraordinary ROI by designing to meet customer
needs and process capability. DFSS can produce the same order of
magnitude in financial benefits as DMAIC. But it also greatly
helps an organization innovate, exceed customer expectations,
and become a market leader.
DFSS is the Six Sigma approach to product design--namely,
designing products that are resistant to variation in the
manufacturing process. Using DFSS means designing quality into
the product from the start. You are preventing wasteful
variation before it happens, thus being able to identify and
correct problems early when the solution costs are less. A
successful DFSS implementation requires the same ingredients as
any other Six Sigma project: a significant commitment and
leadership from the top, planning that identifies and
establishes measurable program goals and timeline, and the
training and involvement of everyone.
Planning for DFSS requires collecting the necessary information
that will allow for error free production of defect-free
products and processes that satisfy the customer profitably.
DFSS attempts to predict how the designs under consideration
will behave and to correct for variation prior to it occurring.
That means understanding the real needs of your customers and
translating those needs into vital technical characteristics of
the product and ultimately into critical to quality (CTQ)
characteristics of the product and process. You can then use
design of experiments (DOE) to develop a robust design that
optimizes efficiency and reduces defects.
Valid and reliable metrics to monitor the progress of the
project are established early in the project, during the Measure
phase if using DMADV. Key inputs are prioritized to establish a
short list to study in more detail. With a prioritized list of
inputs in hand, the DFSS team will determine the potential ways
the process could go wrong and take preemptive action to
mitigate or prevent those failures. Through analysis, the DFSS
team can determine the causes of the problem that needs
improvement and how to eliminate the gap between existing
performance and the desired level of performance. This involves
discovering why defects are generated by identifying the key
variables that are most likely to create process variation.
Failure Mode and Effect Analysis (FMEA) and Anticipatory Failure
Determination (AFD) can be used for both the design of the
product and the design of the process.
DFSS provides a structured way to constructively use the
information learned from these analyses. Armed with real data
produced by the DFSS process, you can develop competent
manufacturing processes and choose processes that are capable of
meeting the design requirements. Further analysis can verify and
validate that the product design will meet the quality targets.
This can be accomplished through peer reviews, design reviews,
simulation and analysis, qualification testing, or production
validation testing.
The benefits of DFSS are more difficult to quantify and are more
long-term. It can take over six months after the launch of the
new product before you will begin to see the true measure of the
project improvements. However, the eventual return on investment
can be profound. This is especially true when the organization
can use the DFSS project as a template for fundamental changes
in the way it develops new products and processes across the
organization.
Peter Peterka is a Master Six Sigma Black Belt for Six Sigma us and has
implemented Six Sigma in a variety of organizations. For
additional information for Six Sigma
Training and
Design for Six SIgma please contact Peter Peterka at http://www.6sigma.us