Modeling and Testing

Abstract

Mojan and Fred discuss the benefits of using failure models with testing. They explore the delicate balance between theoretical analysis and physical testing. While robust design starts with analysis, they discuss how testing serves as the ultimate “insurance policy” for decision-makers and why understanding the “Confidence Stack-up” is essential for a product’s success.

Key Points

Join Mojan and Fred as they discuss the situation when given only one or very few samples for testing.

Topics include:

The Confidence Stack-up: View reliability as a layering process. Each level of analysis and testing adds a layer of certainty, but the final “stack-up” must be enough to satisfy the person ultimately responsible for the decision.
Designing for the Decision-Maker: A key strategy is asking the stakeholder: “How comfortable do you want to be?” This helps determine whether a quick coupon test is sufficient or if a full-system lifecycle test is required.
The Danger of Isolation: Testing components like bearings in isolation often misses the real-world failures found at the interfaces. If you aren’t testing how parts interact, you aren’t testing the true system reliability.
Testing with Purpose: Before a single test is run, it must have a clear audience and a defined purpose. If the test doesn’t produce information that can actually improve the product or aid a decision, it shouldn’t be run.
Validating the New: Any new or unproven model is just a theory until it is validated by data. The model provides the map, but the testing proves the terrain.

Enjoy an episode of Speaking of Reliability. Where you can join friends as they discuss reliability topics. Join us as we discuss topics ranging from design for reliability techniques to field data analysis approaches.