Design for reliability
How do we define reliability?
Reliability can be defined as the probability that a product will keep working beyond its specified interval of time, in the specified working conditions. It implies that if a keyboard has a 99% reliability over 1000 hours, it can still be faulty for 1% of the time within that 1000 hours.
The procedure of designing:
Even slight changes in the system can heavily impact the reliability of the component. Therefore, it is very important to mention the reliability and maintainability targets before any design is undertaken.
For us to know this, it is important to determine the goals, requirements, and specifications of the components.
After we have gone through the requirements, expectations, and specifications of the component, we then need to draft a solution. This step involves selecting the material, and the component, sketching out the industrial design, selecting the user interface, and interactions, electrical and mechanical drawings, and lastly the software development.
Making the right decisions are necessary as it will impact future reliability performance.
As this stage is the foundation stage, there may still be many errors and questions to solve and address, so in the next step, many more tools are implemented in order to refine our understanding regarding the design concerning the reliability.
If the prototypes are available we can begin with the evaluation and experimentation. Our main goal in this step is to find out about the weaknesses of the design. It is also done to increase our understanding of the user environment.
After this step, we can certainly tell the potential failures of the system, and work on it accordingly. The end results from our analysis of the initial design are then checked against specifications we made in the first step. It is done to check if our design is still relevant to the goals and meets the expectations.
We then need to check the solutions with our customers and validate them.
Customers may expect a reliability growth, or may also require a demonstration of the procedure. In any way, our intent is to validate the design, check its reliability, and make sure it meets the end goals.
After we have received feedback from the customer, we may want to monitor our design and improve it accordingly. The team starts with the supply and production part of the design and makes it more refined as now we have collected much more data than what we started working with.
Sometimes only a small amount of variation goes a long way, while we must also keep in mind to not go too astray from the initial design.
So, to summarize the process, we need to keep in mind the reliability expectations and start the design process accordingly.
As we move further and further, we collect more errors and faults that can decrease the reliability of a component and work on it accordingly.
After we have made a well enough design, we sought a third-party validation to understand the design better and make variations accordingly.
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