the Sub · system

Autonomy & safety

She runs herself within hard safety limits, with comms and health telemetry throughout, and layered recovery — drop-weights, a timer release and an acoustic pinger — to bring her home if anything goes wrong.

Decisions & notes

Autonomy & safety

Onboard mission FSM with deterministic validators (geofence, energy reserve, depth floor, deadline); a small local LLM picks among pre-approved options; Claude re-plans at each surfacing. AI advises, validators decide.
Comms: LTE near shore, Iridium offshore, GPS at the surface; passive hydrophone + AIS for vessel awareness.
Recovery (layered): drop-weights + burn wires, an independent potted timer release, a DIY acoustic pinger + commercial ULB, an AIS MOB beacon, hi-vis + strobe.
Health: dual-sourced telemetry; seal-integrity (predive vacuum + BME280) catches a leak hours early.

Parts (20)

LTE modem	Sixfab 4G/LTE kit, Quectel EG25-G	Arrived
Iridium	RockBLOCK 9603 (SMA antenna mode)	Arrived
Leak sensors ×2	SOS leak sensor	Arrived
Iridium antenna	Maxtena M1621HCT-P-SMA (passive Iridium helical, 1616-1626.5MHz, SMA-M, IP67)	Arrived
Water temp	Celsius sensor	Arrived
Burn wire ×2	Nichrome 80, 30 + 32 AWG spools	Arrived
Release hardware	316 springs/pins + 25lb lead shot	Planned
Tether	Fathom Slim 100m (ROV-ready)	Planned
Tether interface	Fathom-X board pair	Planned
Acoustic recovery beacon	Commercial 37.5kHz ULB — RJE ULB-362PL (power-loss auto-activate, ~90-day)	Planned
Hi-vis surface marker	Hi-vis flag/pennant on mast + retroreflective tape	Arrived
Tube sensors ×6	BME280 (temp/RH/baro) — seal integrity	Arrived
Power monitors ×6	INA228 high-side I2C	Arrived
Hydrophone	Aquarian H2a + USB audio interface	Planned
Internal mic	SPH0645 I2S MEMS	Arrived
Leak probes	Extra SOS probes + tips	Arrived
Burn-wire sense	Continuity sense resistors	Planned
I2C mux ×2	TCA9548A ×2 + Qwiic cables	Arrived
Engine room cam	160° USB board cam + pan servo + LED strip	Planned
AIS receiver	dAISy 2+ USB AIS receiver + small VHF whip on the mast	Planned