IntermediateTopic 44 of 102Manufacturing, Robotics & Systems
Fault tree analysis
Top-down logic to find combinations of events causing failure.
In depth
FTA is a top-down deductive method: start with an undesired top event and decompose with AND/OR gates down to basic events; compute probability and find minimal cut sets. Reveals single points of failure and common causes; used in aviation, nuclear and process safety.
Key points
- Boolean logic
- Importance measures
- Common-cause failures
ExampleA fault tree for loss of braking combines hydraulic, electrical and operator-related events.
What is Fault tree analysis?
Top-down logic to find combinations of events causing failure.
Why is it important to understand fault tree analysis?
Fault tree analysis works backward from an undesired top event to find the combinations of failures that could cause it, which is standard in safety-critical systems.
What are AND and OR gates in a fault tree?
An AND gate represents failure only when all inputs fail, and an OR gate represents failure when any input fails.
What are minimal cut sets?
The smallest combinations of basic events that cause the top event, which show the most important weaknesses.
How is Fault tree analysis used in practice?
Typical applications include analysing how a loss of cooling could lead to a reactor overheating, finding the combinations of valve and sensor failures that cause a train to start unexpectedly and assessing the probability of a system failure from component probabilities.
What should I learn before Fault tree analysis?
Study "Failure modes and effects analysis" first (topic 43 of 102 in Manufacturing, Robotics & Systems). It covers the groundwork this topic builds on.
What are the key points of Fault tree analysis?
Boolean logic. Importance measures. Common-cause failures.
Can you give an example of Fault tree analysis?
A fault tree for loss of braking combines hydraulic, electrical and operator-related events.
What comes after Fault tree analysis?
The next topic is "Ergonomics and human factors", which builds directly on this one.
How difficult is Fault tree analysis?
It is classed as Intermediate in Manufacturing, Robotics & Systems (topic 44 of 102). It is an intermediate topic. Work through the beginner topics in Manufacturing, Robotics & Systems first.