High temperature & humidity is a common test condition. For specific failure mechanisms there are models available (or you can create a model) to determine the translation from test to use conditions.
These acceleration models generally only apply to one specific failure mechanisms and do not apply to a system level estimate of life. If the failure mechanism is the dominate failure mechanism for the product, then an ALT exploring just that mechanisms would provide a life estimate. Continue reading
The easiest ALT is one that you operate an item more often then operated by the customer. Removing spans of time the item is not being bent, moved, heated, etc allows you to use time compression.
For example, a home kitchen toaster may be used for a few cycles during breakfast time in your home. In the lab, we can avoid having to wait the day of idle time and just make toast more often than just at breakfast to accelerate the operation of a toaster. Continue reading
Have you ever worked on a project with no deadlines, unlimited resources, and boundless scope? Probably not.
You may have worked under the guidelines of a quality triangle, also known as a project management triangle, iron triangle, or project triangle.
Why is that? Why the limits to our ability to create a product or improve a system? Continue reading
Leadership is not a position or title within an organization. It is an attitude.
You’ve seen the internet meme’s about the difference between leadership and management. There is a difference and while not everyone is going to be in top management, everyone can (and should) be a leader.
As a reliability professional, you are conveniently looked to for leadership. You are expected to use your knowledge and skill to solve problems. To help teams solve problems. To improve the reliability performance of your system and across your industry. Continue reading
Little Compromises and Future Costs
In a recent Seth Godin blog, Counting beans he talks about the eventual costs of little compromises. The immediate benefit may be celebration worthy, yet
But overlooked are the unknown costs over time, the erosion in brand, the loss in quality, the subtraction from something that took years to add up.
This certainly applies to reliability as well. Deferring maintenance just one more month, addressing one more software bug can be done after shipping, and similar small shifts erode reliability of your system. Continue reading
In a customer’s mind, the product works or it doesn’t. If it doesn’t work as expected it has failed. This may or may not be a reliability problem.
A customer or someone using your product brings a set of expectations to the experience. The range of expectations may range from very little to very high functional, value production, and durability.
Failures are defined by customers. Continue reading
Use / Environmental profiles
Did you know that hot air doesn’t rise when there is no or very little gravity?
The electronics used to steer an oil exploration drill head 5 miles deep in the earth experiences 200°C sulfuric acid immersion along with continuous 50,000G shocks.
I used to think the environment under the hood a car was difficult. Continue reading
The term variance is a statistical concept related to the spread or dispersion of a set of data. Second to the mean, it a common value we may calculate.
We find standard deviation easier to understand and use (it uses the same units as the data) whereas variance uses the units squared.
We use variance in quite a few different ways. Let’s review just a few. Continue reading
A Bloomberg articles details the Takata airbag recall series of events. The line that caught my attention is:
…company documents suggesting that Takata executives discounted concerns from their own employees and hid the potential danger… Continue reading
The data analysis course professor tended to focus on the practical application of statistics.
Avoiding statistical theory was fine with me. Learning statistics for me was on how to solve problems, optimize designs, and understanding data. Continue reading
Sigma, σ, is the Greek character we use to represent standard deviation. 6 σ represents the spread of data about the mean. For data with a normal distribution 6 σ includes 99.7% of the data.
The 6 σ design approach incorporates knowledge of the variation that will occur within the design such that the design has is unlikely to fail. Continue reading