Your Reliability Engineering Professional Development Site
A common assumption when comparing three or more normal population means is they have similar (the same) population variances.
ANOVA and some DOE analysis results rely on the underlying data having similar variances. If this assumption is not true, the conclusions suggested by the ANOVA or DOE may be misleading.
It doesn’t take long to check. [Read more…]
Did you shake a wrapped gift as a child?
Sometimes the rattling sound may indicate the hidden contents. A sweater from Grandma would make a muffled sound, while a new Lego set would rustle the many parts.
Your customers may not shake the package to guess its contents, yet your product will experience vibration and shock.
The environments of assembly, transpiration, use, maintenance, etc all include shock and vibration inputs to your product. The operation of your product may include producing vibration and shock loading across the product.
Understanding the basics of vibration and shock will assist you to design your product to operate as expected in the noisy, shaky world.
The rattling about your product experiences is just one of the many environmental and use factors. [Read more…]
The definition of reliability includes four elements.
One of them is the intended environment where the device or system will experience a range of stresses.
The knowledge of where and how an item will operate enables: