The Reef AUV
A free-swimming underwater vehicle: near-neutral buoyancy, six degrees of freedom, and a floaty momentum you learn to anticipate. Pilot the twin through a reef before you waterproof a thing.
Drive it in real physics.
The four-part build starts with this: the design as a real MuJoCo twin you can pilot right now on Play. Take the controls, then build the body that runs it.
Dive the twin
A free 6-DOF submarine in real physics. Near-neutral buoyancy gives it a heavy, gliding feel; thrust, yaw, pitch, and dive on any controller through a nose or chase view.
Thrust, yaw, pitch, and dive on any controller — collect the glowing markers.
▶ Drive the twin on Play ↗Four parts, one loop.
Body, brain, driver, policy. The design forces no single board — only that whatever you pick can take the commands and run the policy.
A printed, floodable hull
A printed frame with thruster mounts and a sealed electronics pod. Print in ASA or PETG for the water; foam and ballast tune it to near-neutral buoyancy.
Dry, in the pod
Thruster control plus a policy, sealed from the water — on the board or on a surface tether. Pick from the options below.
Browser → thrusters
Six thruster commands per tick stream to the ESCs over the driver registry. Waterproofing changes where the brain sits; the twin's commands map straight across.
Setpoints → thrust mix
Pilot by hand to gather data in the current, then hand a policy the same thrust vector it drove in the sim.
Ways to power the same body.
Cheapest to heaviest. Every one drives the identical printed body and runs the same policy.
Espressif ESP32-S3
~$8Thruster control in the pod, with the policy on a surface tether or the board itself.
Raspberry Pi 5 (sealed)
$80+On-board policy and camera, sealed in the pod.
NVIDIA Jetson Orin Nano
$249Vision in murky water — the heavy, capable option.
Full specs and roles for every board: Digital Brains →
Open robots like this one.
The Maker Atlas maps real, open Physical-AI robots to each of our builds. These are kin to this one — open a profile to trace its boards, sensors, and source.
BlueROV2
The category-defining open-software ROV — a Navigator FC on a Pi 4, a 1080p low-light camera, sonar, and 6–8 T200 thrusters on ArduSub. Open software, machined hull.
In the wildBlueBoat
The open-software autonomous surface vehicle (ArduRover + BlueOS) — a Navigator + GPS catamaran for survey; the surface sibling to BlueROV2.
In the wildAruna ROV
An open, modular ROV built from off-the-shelf + 3D-printed parts with a camera module — one of the few genuinely printable open underwater robots.
In the wildOpenFish
ETH SRL's open, CC-licensed, FDM-printable soft robotic fish — full STL/CAD on OSF; a locomotion platform you add perception to.
See how they all connect: the Maker Atlas →
Live now: the twin. In progress: the physical unit.
The sim twin on this page is real and live today. The printable body and the driver are specced against the sim-to-real registry; the first physical unit is being assembled, and the STL pack and step-by-step land here the moment it's verified on real hardware — not before.
Design its body, program its brain.
Take this build into the Studio: model and export its printed parts on the CAD kernel, and write the MicroPython that runs on its board. Both open as full-screen workspaces.