MTBF and MTTR: The Numbers That Predict Robot Cell Uptime
Definitions that matter
| Metric | Meaning | How it is used |
|---|---|---|
| MTBF | Mean time between failures | Predicts how often you will stop |
| MTTR | Mean time to repair | Predicts how long you will be down |
| Availability | MTBF / (MTBF + MTTR) | The number production cares about |
| OEE | Availability x performance x quality | The number management cares about |
Improving the ratio
- Raise MTBF with preventive maintenance, better part presentation and correct duty margin.
- Lower MTTR with spare parts on site, clear fault codes and trained first-line staff.
- Do both by keeping a fault log and reviewing the top three causes each quarter.
Be careful with vendor numbers
MTBF quoted from component data is not the same as observed cell uptime. Ask for field data from comparable installations, and validate with your own log during the first 90 days.