Interactions, Optimization, and Measurement Strategies

Many people are under the misconception that interactions are not considered in Taguchi Methods; however, the opposite is true.

In fact,Dr. Taguchi considers interactions one of the most important issues in his approach.

The S/N Ratio is an index for the robustness of quality, and it shows the magnitude of the interaction between "control factors" and "noise factors." Control and noise factors must be assigned to different groups for the study of robustness, which is significantly different from the traditional DOE approach, where there are no distinctions between control and noise factors.

A key difference of Taguchi Methods is the emphasis on measuring the right things for data collection. Instead of measuring symptoms caused by variability of the function, such as defects or failure rate, we measure an energy-related response.

Any system uses energy transformations to accomplish the intended function. Reducing variability of the energy transformations will minimize or eliminate the symptoms.