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Survivability under spin
Electrical interface
5.3
- Max Operating Temperatures of Components (C):
- Tank Servos: max coil temp → 130, continuous (preferable) operating temp → 90
- On Board Computer (OBC): -40 to 85 (assuming power supply 1.62V to 3.6V)
- Pressure Sensor: -40 to 125
- Watchdog timer circuit: -40 to 125
- Thermocouple to digital converter: -55 to 125
- RS-422 Transceiver Bus/Data: -65 to 150 (storage temperature), 150 max junction temperature, **highly recommended: -40 to 85
- Thermal strap details: STCH_Thermal Straps_Submitted_Q2 2024.pdf
7.1 -
| Failure Mode | Detection | Isolation / Safe Mode | Recovery |
|---|---|---|---|
| Sensor bias / dropout | Redundancy, out-of-range checks, rate checks, residuals | Flag sensor invalidity, use backup, and reduce authoriuty | Sensor reset → offset compensation where valid |
| Unexpected torque | Model vs measured residuals | Switch to damping mode, inhibit impulses | Let residuals decay and re-estimate states |
| Spin-axis misalignment | Orientation vs expected dynamics | Reduce authority, re-acquisition | Re-estimate axis and update control parameters |
| Partial power loss | Voltage / Current thresholds | Disable non-essential processes and maintain survival | Gradually restore functions as power stabilizes |
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FDIR = Continuously:
Observe system state
Compare to model/expectations
Flag anomalies
Enter a safe mode
Attempt recovery
Only return to nominal when consistent
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