Page 166 - Design for Six Sigma a Roadmap for Product Development

140 Chapter Five

Relationships between technical CTS and WHATs arrays are often
used to prioritize customer wants and needs by filling the relationship
matrix of QFD. For each customer want, the DFSS team has to assign
a value that reflects the extent to which the defined CTS contributes
to meeting the WHATs. This value, along with the importance index of
the customer attribute, establishes the contribution of the CTSs to the
overall customer satisfaction and can be used for prioritization.
The analysis of the relationships of customer wants and CTSs allows
a comparison to other indirect information, which should be under-
stood before prioritization can be finalized. The new information from
the planning matrix in the QFD must be contrasted with the available
design information (if any) to ensure that reasons for modification are
understood. External customers on the DFSS team should be consulted
to validate such changes and modifications. When customers interact
with the team, delights often surfaced which neither would have inde-
pendently conceived. Another source of delighters may emerge from
team creativity as some features have the unintended result of becom-
ing delights in the eyes of customers. Any design feature that fills a
latent or hidden need is a delight, and with time, becomes a want.
There are many means to create innovative delights by tools such as
brainstorming, axiomatic design (Chap. 8), and TRIZ (Chap. 9).
Delighters can be sought in areas of weakness, competition bench-
marking, and technical, social, and strategic innovation.

5.3.6 Translating CTSs to functional
requirements (FRs) (DFSS algorithm step 2)
The purpose of this step is to define a Six Sigma design in terms of cus-
tomer expectations, benchmark projections, institutional knowledge,
and interface management with other systems, and to translate this
information into CTSs and later into technical functional require-
ments targets and specifications. This will facilitate the physical
structure generation as proposed by the axiomatic design (Chap. 8)
method. In addition, this step will provide a starting basis for the
logical questions employed to define the physical structures of design.
A major reason for customer dissatisfaction is that the design spec-
ifications do not adequately link to customer use of the product or ser-
vice. Often the specification is written after the design is completed. It
may also be a copy of outdated specifications. This reality may be
attributed to the current planned design practices that do not allocate
activities and resources in areas of importance to customers and that
waste resources by spending too much time in activities that provide
marginal value, a gap that is nicely filled by the DFSS project algo-
rithm. The approach is to spend time upfront understanding customer