How Can TRIZ Apply to Six Sigma?
By Tom Kling
TRIZ is the Russian acronym for the “Theory of Inventive Problem Solving,” developed in the mid-1940s. Of the dozens of TRIZ tools and ideas, a few of the basic ones are particularly useful with Six Sigma: in DMAIC (Define, Measure, Analyze, Improve, Control) and DMADV (Define, Measure, Analyze, Design, Verify).
- The ideal final result (IFR) is a description of the best solution, neutral to how it is achieved. In Define, an IFR can help establish a multigenerational plan or define success for a project. It can also be used to establish criteria for a Pugh matrix in Improve or Design.
- In Analyze, function analysis identifies insufficient functions, contradictions and the source of harmful actions or by-products.
- Technical contradictions, often used in Analyze, are cases in which improving one characteristic of a system causes the worsening of another. For example, in a vehicle, improved crash worthiness could mean fuel economy gets worse.
- Inventive principles are a list, usually with examples, of idea-triggering counterparts to contradictions. They outline mechanisms of operation in Improve or Analyze. In the case above, the principle of composite materials might suggest plastic foam inside tubing to absorb the energy of a crash, instead of adding more heavy solid steel.
- Scientific effects can be used for resolving contradictions through the application of physical, chemical, biological and geometrical phenomena, such as resistance heating or centrifugal force. There are thousands of effects, most accessed via software, often in Improve or Design, once function analysis highlights a need.
- In the Measure and Analyze stages of DMADV, quality function development, also known as the house of quality (HOQ), is used to organize and prioritize customer needs, but does not fulfill them. TRIZ inventive principles can resolve conflicts from the roof of the HOQ, and the application of scientific phenomena can satisfy insufficient functions in a functions-to-design-measures matrix.
When it comes to tough problems, an investment in TRIZ can return manyfold in the simplicity, speed and efficiency of its solutions.
Tom Kling is a Master Black Belt and TRIZ expert with The Dow Chemical Co.