FMEA

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Failure Mode and Effect Analysis or FMEA is a structured method to analyze component and system reliability. It is a framework to look at how something fails (failure mode) and what happens when it does (failure effect).

An FMEA is required in FSAE for certain parts of an EV car. The competition puts together a somewhat comprehensive presentation on completing the competition's required document submission here:


Basics

Analytical Lens

At a lay level, a FMEA should be a list of different ways things can go wrong, as in: "what if this part broke?". Each "what-if" being looked at in multiple ways:

  • How could this part break? (Failure Mode)
  • What will happen to the car if this thing goes wrong? (Failure Effect(s))
  • How likely is this thing to go wrong?
  • What can we do to stop this from happening?

Additional detail can be included at whatever level of depth is deemed appropriate. Some further questions to ask include:

  • What could cause this failure?
  • How could we detect a failure has occurred?
  • How could we detect a failure will occur?
  • What physically happens to the parts that are directly connected?
  • What happens to the functionality of the system that this is a part of?
  • To what extent is the functionality of the car effected?
  • If this failed, would the car continue to be rules compliant?
  • If this failed, could the driver be in danger?
  • If this failed, could a bystander or track volunteer be in danger?
  • How quickly can this be repaired if it failed?
  • Would a new component have to be bought/machined or is this meant to be repairable?
  • How long is the lead time for a replacement component?

Analytical Techniques

FMEA is a fundamentally qualitative effort to manage risk. There are many ways to put numbers to different facets of the process, but frequently "fuzzy" approaches are used where there is no way to quantify unknowns.

When to use FMEA

Design Phase

The strength of FMEA is greatest when utilized during the design phase of a build. Early in the design, it is possible to determine critical failure outcomes, risk levels, and experience or research can aid in determining failure points. As the design matures, component specs, features and integration requirements should be carefully investigated to pre-empt possible failure modes. This includes but is not limited to stress concentrators, build tolerance and tolerance stack-ups, material fatigue, wear-in, wear-out, driver error, competition volunteer error, load paths, road load, team-members being lazy or ignorant, poke-yoke, torque specs, fretting, dirt and grime, contamination, corrosion, water ingress, extreme cold or extreme heat etc.

Manufacturing Phase

Testing Phase

Planning Phase

Types of FMEA

System/Functional FMEA

Process FMEA

Design FMEA

Manufacturing FMEA

Software FMEA

How to Make an FMEA