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3 Ways to do Reliability Allocation #2

3 Ways to do Reliability Allocation #2

This is our second article about the 3 ways to do reliability allocation. In the first article, we set the scene. We talked about the reliability design cycle that needs to be implemented to make sure what we do will actually work. Will actually matter. In this article, we go through the six steps of reliability allocation. You need to do the preparation work first. But … we are all about keeping it simple. Making it exhaustive and complicated means you are wasting your time.

If you want to learn more about a straightforward approach to reliability allocation – read this!

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3 Ways to do Reliability Allocation #1

3 Ways to do Reliability Allocation #1

If we have even a moderately complex product, we often need to break up our design team into smaller groups. Perhaps electronic, mechanical and hydraulic teams. Perhaps teams for specific functional components. And these teams need to work at least partially independently. So what do we do if we have a system reliability goal? What goals do we pass on to our smaller teams? This is where reliability allocation comes into play. Reliability allocation is often portrayed as a very complex, very involved and extremely exhaustive process. It should never be! In fact – the more exhaustive you make, the less likely it is to work.

If you want to learn more about a straightforward approach to reliability allocation – read this!

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MTBF of a Human

MTBF of a Human
“What’s the MTBF of a Human?” That’s a bit of a strange question? I ask this question in my Reliability 101 course. Why ask such a weird question? I’ll tell you why. Because MTBF is the worst, most confusing, crappy metric used in the reliability discipline. Ok maybe that is a smidge harsh, it does have good intentions. But the amount of damage that has been done by the misunderstanding it has caused is horrendous. MTBF stands for “Mean Time Between Failure.” It is the inverse of failure rate. An MTBF of 100,000 hrs/failure is a failure rate of 1/100,000 fails/hr = .00001 fails/hr. Those are numbers, what does that look like in operation? [Read more…]

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The Design for Risk Idea

The Design for Risk Idea

Yesterday had the chance to review the long list of Design for X topics. Assembly, environment, maintainability, and of course reliability, plus about a dozen other areas of focus. How is a design team to navigate all these different sets of constraints and objectives along with crafting a solution that works?

With a little creativity, you could relate every Design for X topic to reliability. Easier to assembly, fewer assembly errors leading to field failures, for example.

Another way to think about the Design for X space is to consider a superset instead. What are all these design considerations really about? What is common, including the design for reliability topic? With a little thought, it seems clear to me that we all are really considering how to identify and manage risk. [Read more…]

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Software Design and How it Influences Reliability

Software Design and How it Influences Reliability

My first system project was a new TV design by HP.   My first actions were to interview all project engineers and discuss their function in the program.  I wanted to know what they were thinking and the approach they would use.  From this interview process, I could start defining the Functional Architecture (Ref. REI book p 22-25) and start forming the reliability strategy. [Read more…]

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Tips on Presenting Reliability Data Well

Tips on Presenting Reliability Data Well

“Speak with Data!” commanded my former general manager. “Let the Data Sing” is an article I wrote long ago. We all have data, often too much data. We like to present based on what the data says. Yet, sometimes the speaking with data is not clear.

If you’ve done the data gathering, the analysis, the summary, all based on the data, how can you best reveal what the data says to enhance your results and recommendations?

Just because you can add a 3D pie chart doesn’t mean you should. Crafting meaningful charts is only one part of the puzzle. You also have to present the data in a clear and meaningful manner. Here is a set of suggestions to consider the next time you are preparing and presenting when data is involved. [Read more…]

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(Thermal) Accelerated testing – how do I do it?

(Thermal) Accelerated testing – how do I do it?

As we make things to be more and more reliable, it gets harder and harder to make them fail in reliability tests. On the one hand – that’s great. On the other hand – that sucks if we want to use testing to help measure reliability. So if we are focused on measuring reliability through testing, we need to make our product or system fail in test conditions (without making it less reliable) but make sure these test conditions can somehow be translated back to how customers are going to use it. This is where accelerated testing comes in. [Read more…]

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Reliability Testing on OEM Systems

Reliability Testing on OEM Systems

Introduction — OEM Systems with Limited Samples

I was assigned to a new project at HP as a reliability engineer was to develop a rear projection, large screen TV.   As the project was being defined, I was informed that an Asian Original Equipment Manufacturer (OEM) would be developing and manufacturing the HW while HP developed the SW.  HP would own the service center support of field issues.  My role was to represent the customer and evaluate the reliability of the final product. [Read more…]

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Prioritizing Urgent v Important Reliability Tasks

Prioritizing Urgent v Important Reliability Tasks

As reliability professionals, we have a lot to do. Risks to identify, failures to analyze. Plans to draft, numbers to crunch. Meetings, writing, research, and leading fill the day.

The list of tasks that you have before you each day is impressive and daunting. So, how do you focus on what actually requires your attention and not just the tasks that get your attention?

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Reliability Actions to be Taken in the Early Stages of an R&D Project

While working at HP as a failure analysis engineer, I was asked to join a new R&D project that needed a reliability engineer.   My background was in Physics with little experience in reliability other than knowing that failures occur because reliability goals were not met.  At HP, reliability engineers were integrated on each HP project by rotating many disciplines of engineering from various parts of the organization. [Read more…]

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Building on a Good Reliability Goal

Building on a Good Reliability Goal

If we set a product reliability goal of 99% reliable over two years in the requirements document, what are we supposed to do tomorrow? On the other hand, if our goal is to write 1,000 pages for the next great novel by the end of the year and we have no pages written so far, well, we should write a page or two tomorrow.

A good goal provides a vision, a measurable milestone, a target. What it lacks is what we do from now till achieving that goal. If the goal is 1,000 pages in 365 days, we may want to set up a process to write at least 3 pages per day.

So, given a reliability goal, what do we do tomorrow, next week, and each week between now and when the goal is due?

A Good Reliability Goal

In previous work, I’ve written about setting reliability goals, connecting the goal to customer expectations, technical capability, and business needs. Plus, have written about the four (five) parts of a complete goal, including Function(s), Environment, Duration, and Probability (and all four continue to get more difficult as customers expect more).

A well-stated reliability goal provides direction and a measurable target for the entire team. It provides a basis to compare progress and to help frame “is the design reliable enough yet” discussions.

This is all well and good, yet is it enough? [Read more…]

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3 Ways to Improve Your Reliability Thinking

3 Ways to Improve Your Reliability Thinking

I often joke that being a reliability engineer makes it difficult to get on an airplane. Yet air travel is by far the safest method of transportation. Maybe I just think about failure too much.

When a project manager views the day’s tasks, she sees timelines, connections, dependencies. When a marketing manager views a product idea, she sees benefits, sales channels, and profits. When a reliability engineer views a prototype, she sees the many ways it can fail.

Underlying how we view the world includes our assumptions, reasoning, and experience. We understand the world around us via the set of filters we use. We form conclusions and make decisions much the same way. Quickly and mostly automatically. [Read more…]