Your Reliability Engineering Professional Development Site
What role does ‘wishful thinking’ play in interpreting reliability test results? Hopefully, none. A well-designed test will likely provide meaningful results. You and your team may not like the results, yet the results will be clear. [Read more…]
A plan is a road map toward a destination. It provide guidance toward a goal. The idea of a plan is to consider the path forward, the knowledge necessary to acquire, and the decisions along the way.
No plan is perfect other than those that successfully accommodate the successes and setbacks along the way. No plan can anticipate all the information yet to be uncovered, yet it can set a course to deliberately uncover what is necessary to move forward.
Reliable products are also green. This is a relatively simple argument: If an item is designed and built well, it lasts a long time, thus avoiding landfills. Years ago, when living in northern Bavaria, the apartment had a full bedroom set. The entire set was both beautiful and functional. When asked about the furniture, I learned it was over 300 years old. [Read more…]
Reliability testing is expensive. For that expense, the testing results should provide timely, meaningful results. Results that provide actionable information and insights.
The idea of running a set of standard tests or tests that we ‘commonly run’ in many cases has little value. Each test (experiment) should be conducted for specific reasons related to the current project and current knowledge. [Read more…]
I often describe reliability work as we do everything quality does, and we do it over time. Quality folks may disagree. What is not in dispute is that in reliability engineering, we use a lot of different ‘quality’ tools. That is because many quality tools lend themselves to data analysis and problem-solving, [Read more…]
One of the very first plots to do with a string of data is a simple run plot. This plot provides information related to location, trends, patterns, and anomalies, The plot of the data over time is a rather informative chart.
You have most likely constructed many run charts; if not you really should. This short introduction to the run chart will cover creating and interpreting them. Plus we’ll mention a few cautions and tips, as well. [Read more…]
When a reliability engineer or manager does their job well, the product just works as expected. Maybe even a little better than expected. There isn’t any major problems that need a hero to resolve.
Work done well, may go unnoticed. To avoid that you need to master the art of promoting successes without coming across as bragging or boasting. For your career advancement, you need to be both successful and likable.
For your program and ability to influence outcomes, you also need to be seen as successful, valuable, and again likable. [Read more…]
Only some discussions about reliability go well. Some conversations make it obvious reliability is an afterthought or considered a barrier to creating and shipping products. Other conversations seem to support reliability work, yet really are little more than lip service. Then, there are meaningful conversations that improve the reliability culture within the organization. [Read more…]
Stratification implies layers or differences. A quick test for soil composition is to place a sample of soil with water in a clear jar and give it a shake. The sand, silt and loam will settle at different rates and create a layered appearance within the jar over time. The height of each layer provides information about the proportion of each type of soil within the sample.
Stratification as one of the seven basic quality tools (some lists use a run chart or flowchart instead) the idea of layers or differences still applies. The idea is to identify potentially meaning differences within a sample set. [Read more…]
While in the US Army many years ago, I took command of an artillery battery. My first day included sitting down with my boss, the battalion commander. I’ve used the advice he gave me every day since.
He said that I needed to make decisions. It’s great when they are good decisions, you can learn from decisions that don’t work out well. He also said the only thing not allowed is not making a decision.
I learned that decision-making is a process and that I could get better at it with practice and feedback, and I did. [Read more…]
A histogram is a graphical representation of a set of data. It is useful to visually inspect data for its range, distribution, location, scale, skewness, etc. There are many uses for histogram, there you should know how to create one.
Let’s explore a set of data and create default histograms using a variety of methods. If you have a way to create a histogram using some other method or software package please send it over and we’ll add it to the article. [Read more…]
DFR has been a term in and out of fashion for some time—one of the many DFX type programs. DFR, unlike some of the other Design for X programs, has to exist within the overall culture of the organization to be successful. The premise that design occurs at the point of decision implies that each design may have the appropriate information to consider the decision’s impact on reliability performance properly. [Read more…]
In the situation where you have a sample and would like to know if the population represented by the sample has a mean different than some specification, then this is the test for you. In this case, you do not know the actual variance of the population, you just have a sample.
This test is often the second one in a textbook that describes hypothesis testing. It is a useful hypothesis test and applies in many situations as we rarely know the population variance. [Read more…]
The essence of creating a reliable product involves making informed decisions. Informed related to the implications of the various options on reliability performance. Yet, these decisions, made nearly every day during the early stages of a product’s lifecycle are fraught with uncertainty.
There is an approach that instead of making perfect decisions every time, we instead focus on making decisions that allow us and others to learn the necessary information to then make better decisions. [Read more…]
The more you understand the failure mechanisms, the easier it is to design an accelerated life test (ALT). Yet, we often do not have all the information we would like to draft an ALT. So, what do we do then?
[Read more…]