The fish
A 350–450 mm soft-bodied biomimetic swimmer, mass 600–900 g wet, with a swappable microbial fuel cell stack as its body cavity. The pollutant is the fuel.
Form factor
| Spec | Value |
|---|---|
| Length | 350–450 mm (carangiform / thunniform) |
| Mass | 600–900 g wet |
| Body cavity | ~250 mL total |
| Gut cartridge | ~80 mL |
| Battery + supercap | ~40 mL (5–10 Wh Li-ion buffer) |
| Electronics + sensors | ~30 mL |
| Actuator + propulsion | ~50 mL |
| Hull skin | Silicone elastomer (Ecoflex / Dragon Skin) |
| Internal frame | PETG or PLA-PHA (biodegradable in marine env) |
Two chassis variants
shoal-chassis-A — thunniform. Cable-driven brushed DC tail. Top speed ~0.5–0.8 m/s, average draw 1–2 W at cruise. Use for fast deployment and large-area survey. Forked from OpenFish and the FISHR expansion.
shoal-chassis-B — bistable. Carbon-fiber hair-clip mechanism (CarbonFish derivative). 5–10 Hz undulation from a single low-power actuator. Top speed ~0.3–0.5 m/s, average draw 0.05–0.2 W. Use for slow forage and energy-positive cruising. The default for foraging missions.
Power profile
| Mode | Draw | Notes |
|---|---|---|
| Sleep | < 100 µW | IMU + MFC monitor wake-on-event |
| Cruise | ~10 mW | CGRA running CPG, sensors low rate |
| Forage | ~30 mW | PIM running plume policy, all sensors |
| Comm burst | 200–500 mW for 1–30 s | Acoustic transmit / optical at dock |
The fish is primarily MFC-powered. The Li-ion is a buffer; the supercap absorbs actuator surges. See Architecture §2.6 for the full power tree.
Sensor suite
Always-on (~5 mW total): 9-DoF IMU, pressure, temperature, MFC monitor, bilateral lateral-line MEMS pressure array.
Event-triggered (~50–200 mW when active): bilateral electrochemistry pair (DO, ORP, pH, conductivity), optical absorbance / fluorescence, CMOS camera with blue-green LED, hydrophone.
Cartridge-specific sensors are added by the active gut cartridge — see the cartridges page.