Page 334 - Design for Six Sigma a Roadmap for Product Development

304 Chapter Nine

Solution. The situation clearly calls for the solution providing separation
of contradictory properties in time. The pile is sharp during the driving
process, and then its base is expanded, which could be realized by a small
explosive charge.

During driving After driving

Explosives

Approach 3: Separation between the components. Separation between
the components means that one component has property P, while
another component is given an opposite property P.
Sometimes we can limit the number of properties of the component
involved in the conflict to one, and we introduce another component to
have another property.

Example 9.10
Problem. A conventional bench vise is designed to hold objects of regular
shapes. To hold objects of irregular shapes, special jaws have to be installed.
Fabrication of such jaws requires a time consuming and laborious process.
Contradiction. The jaw must be rigid to clamp the part, and they must be
flexible to accommodate themselves to the part’s profile.
Solution. It is proposed to use the principle of separation of opposite prop-
erties between the system and its components to make a jaw. Two flexible
shells filled with a loose material are fixed to upper and lower vise jaws. The
workpiece (parts) is placed between the shells and pressed. Once the shells
envelope the workpiece, a vacuum pump is used to set the final shape,
fastening the workpiece reliably. This design increases productivity and
reduces the need for building a specialized fixture.