Generating Ideas and Concepts - Medical Device Design: Innovation from Concept to Market - page 108

because someone doesn't know the right word does not make it a bad idea. Be very aware of
intellectual snobbery.

6.4.2 Inversion (or Word Association)
This is a very simple technique used to promote lateral thinking. The process is simple; write
down a word or phrase associated with the concept, e.g., white, then write down the opposite
(or its antithesis), i.e., black.

If I may I will give you an example from the diesel engine industry. All cars, lorries, and
trucks have a fuel line to the engine. One particular fuel line was vibrating in use at a
particular frequency F and failing ( Figure 6.2 ). The obvious answer was to add more clips to
stiffen it. However, inverting the solution meant taking away a clip to make it more flexible.
Both solutions worked, but the removal of a clip was the cheaper solution as they were
making thousands of engines per year.

Hence inversion simply examines the opposite. If someone says it should be “stiff,” also write
down “flexible.” If someone says it should be “fast,” also put down “slow.” Some examples
are shown in Table 6.1 .

Original fuel line

Deflected shape when vibrating at frequency F

Deflected shape with additional clip, frequency is
higher than F

Deflected shape when clip is moved, frequency is
higher than F

Deflected shape when clip removed, frequency is
lower than F

Figure 6.2
Example of the inversion technique used to a solve vibration problem with a fuel line.

Table 6.1: Example of Inversion Technique

Specification Slow Stiff Dark Smooth Shiny

Inversion Fast Flexible Light Rough Dull