the Sub · system

Hull & structure

A 4-inch torpedo hull of four sealed, locking tubes — one for electronics, three for batteries — with a camera nose dome and a finned tail. ~2 m, ~37 kg, sized to carry to the water yourself.

Decisions & notes

Hull & structure

  • Ø4″ torpedo, four 4″-series aluminum locking tubes (electronics 300 mm; the 3 battery tubes 400 mm - sized by 21700 packing in the 103 mm bore) (1000 m-rated): 1 electronics + 3 battery, plus nose dome, finned tail, and the VBS.
  • ~2.0–2.2 m, ~37 kg — sized to launch solo from shore.
  • Modular: diameter stays 4″ so all 4″-class parts stay valid; a 4th bank / longer 400 mm tubes are a planned endurance upgrade.
  • Free-flooding 3D-printed fairings, landing skids, and a sample caddy round out the structure.

Parts (14)

End caps ×6WTE 4" alu end caps (mixed hole patterns)Arrived
Dome4" polycarbonate dome BR-107201 (1000m)Arrived
O-ring flanges ×8WTE 4" O-ring flangeArrived
Clamps ×8Enclosure clamp 4"Arrived
Penetrators ×20WetLink M10 (assorted seal sizes)Arrived
Penetrator blanks ×6WLP blank M10Arrived
Vent/vacuum/PRVVents ×3 + vacuum plug + PRV ×3 + backfillArrived
Flotation foam ×3R-3318 large blockArrived
BR sundriesMolykote 111, picks, desiccant, WLP wrenches, O-ringsArrived
Sacrificial anodeUS Marine Products MAGNESIUM anode (freshwater) — bolt-on, bonded to hullArrived
Mast antenna feedthroughsSMA bulkheads + potting for GPS / LTE / AIS-VHF mast antennas (design TBD with mast)Planned
Manipulator — gripperBlueRobotics Newton Subsea Gripper (300m, 62mm jaw, 97-124N)Planned
Landing skids/feetLanding gear — HDPE + 3D-printed feet, wide footprintPlanned
Sample caddyFree-flooding sample basket — 3D-printed, multi-compartment + mesh + latchPlanned