Frequently Asked Question

Decision-matrix method

Concept selection compares alternatives against requirements, risk, manufacturability, service, cost, schedule, sustainability, and evidence maturity. Define the criteria and scales before scoring. Review sensitivity to weights and uncertain scores; a close result means more evidence is needed.

Worked example

For weights 0.5, 0.3, and 0.2 and concept ratings 8, 6, and 7, the score is 0.5×8+0.3×6+0.2×7 = 7.2. Record the rationale, confidence, and disqualifying risks beside the arithmetic.

Engineering check

For Concept Selection with a Decision Matrix, maintain traceability from requirement to risk, design output, evidence, and approval. Record the configuration, acceptance criterion, test or analysis conditions, open actions, and residual risk. A method is not complete when the document is filled in; it is complete when the evidence supports the decision and affected controls are updated.

Engineering note

For Concept Selection with a Decision Matrix, state the intended use, input range, dominant mechanism, units, boundary conditions, acceptance criterion, and evidence owner. Use an independent balance, limiting case, repeat measurement, or sensitivity check to challenge the result. Document the configuration and uncertainty so another engineer can reproduce the reasoning and determine whether the result remains valid after a design, material, boundary, or process change.

Engineering note

For Concept Selection with a Decision Matrix, state the intended use, input range, dominant mechanism, units, boundary conditions, acceptance criterion, and evidence owner. Use an independent balance, limiting case, repeat measurement, or sensitivity check to challenge the result. Document the configuration and uncertainty so another engineer can reproduce the reasoning and determine whether the result remains valid after a design, material, boundary, or process change.