Build log

Everything we built. Including what broke.

Every part of D.R.E.A.M.S, from the first sketch to the V3 boards, with an honest status on each entry.

01 · The full log

32 entries, three generations.

Filter by version or by status. Every entry is something we designed, built, tested or tried and abandoned.

Hand-drawn concept sketch of the catamaran with a requirements list
V1 · Spring 2026Designed

The first concept sketch

Requirements and the twin-hull layout, on paper.

SolidWorks model of the catamaran bridge with the winch
V1 · SolidWorksDesigned

Bridge and winch in CAD

The deck that ties the hulls together and carries the winch.

CAD model of the V1 sensor pod
V1 · SolidWorksDesigned

Sensor pod in CAD

A sealed pod for the sensors, lowered on a tether.

The 3D-printed V1 sensor pod with electronics inside
V1 · Sensor podBuilt

Printing the sensor pod

3D-printed and wired.

Assembling and wiring V1 outdoors
V1 · AssemblyBuilt

Wiring and assembly

Putting the boat together outside.

A white 3D-printed figure of Grace from Project Hail Mary sitting on V1's clear acrylic deck
V1 · DeckBuilt

Grace on deck

Our 3D print of the Grace figure that Rocky makes in Project Hail Mary. Printed for fun.

Brushing marine epoxy onto a printed hull
V1 · HullBuilt

Epoxy-sealing the printed hull

PLA hulls sealed with marine epoxy.

A printed V1 hull section held up after its epoxy coat, black at the bow and red behind
V1 · HullBuilt

The sealed hull

Glossy after its epoxy coat, black at the bow and red behind.

Our room in London set up as a workshop, with a hull section hanging over a taped-down drop sheet
V1 · LondonBuilt

A workshop in our room

A hull section cures over a drop sheet while the build takes over the desk.

The V1 winch that lowers the sensor pod
V1 · WinchBuilt

The sensor-deployment winch

Lowers the pod to the bottom to sample.

V1 · WinchTested

Weight-testing the winch

A load on the line, with the winch run from the RC transmitter.

Line drawing of an early jet-propulsion unit
V1 · PropulsionFailed

Jet drive

An early jet-propulsion experiment. A dead end, but a useful one.

V1 at the edge of St Katharine Docks
V1 · LondonTested

Water test at St Katharine Docks

Navigated to GPS waypoints on its own, with a radio link of about 1 km.

Sketch of the display stand for V1: a base with a curved cradle and two triangular supports
V1 · StandDesigned

Sketching the display stand

A stand to show V1 at the Creators' Showcase and in our class presentation.

Visitors gathered around V1 at the Creators' Showcase
V1 · NU LondonShown

Creators' Showcase

Shown at the inaugural Creators' Showcase, Northeastern University London.

Talking visitors through V1 at the showcase, with a laptop and the RC transmitter on the table
V1 · NU LondonShown

Demoing V1

Talking visitors through the boat and its radio controls.

CAD model of the V2 twin hulls
V2 · Summer 2026Designed

Hull CAD

Hull geometry refined for stability and flow.

A printed section of the V2 hull
V2 · HullBuilt

First printed hull section

The V2 hull, printed in sections.

Fiberglass cloth wetted out with epoxy over a printed hull
V2 · HullBuilt

Fiberglass over the print

Wetted out with epoxy for stiffness and water resistance.

KiCad layout of the first custom PCB
V2 · ElectronicsDesigned

Custom PCB, REV 01

Our first custom board, laid out in KiCad.

KiCad layout of the second PCB revision
V2 · ElectronicsDesigned

PCB REV 02

Consolidated power, radio and sensor headers.

Bringing up the custom PCB on the bench
V2 · ElectronicsBuilt

Board bring-up

Powering up and testing the board on the bench.

Stereo camera rig on the test bench
V2 · VisionTested

Stereo tracking on the bench

Per-object depth from a stereo pair, with YOLOv8 detection.

The V2 command-center dashboard
V2 · SoftwareBuilt

Command-center dashboard

Ran on the Pi 5. Now a live demo you can try.

V2 · BenchFailed

Bench testing

Exposed flaws in motor control, power and safety. We redesigned the whole system.

3D render of the V3 carrier board
V3 · Fall 2026Designed

Carrier board, rev F

130.6 × 101.5 mm, 4 layers, 141 parts, fully routed.

3D render of the V3 sensor-pod board
V3 · Fall 2026Designed

Sensor-pod board, rev B

48 × 63 mm. Talks to the boat over an RS-485 tether.

V3 · HullIn CAD

Modular hull

The new V3 hull, in CAD now.

V3 · SoftwarePlanned

Firmware

Autonomous waypoint navigation, surface sampling and depth logging.

V3 · FieldPlanned

Field trials

Autonomous surveys of small bodies of water.

CAD model of a cycloidal gearbox joint for the arm
LaterIn development

Sample-collection arm

A deck arm that works with the winch. Its cycloidal joints are in CAD.

LaterPlanned

Sediment sampling

Bring sediment back from the bottom without sending a diver down.

02 · Three generations

V1 · V2 · V3

Each version fixes what the last one taught us.

V1CompleteSpring 2026

Proof of concept

Built in one semester in London: three RP2040 microcontrollers on the boat, shore station and pod, a 3D-printed PLA hull, and a 433 MHz radio link that reached about 1 km to shore.

In its water test at St Katharine Docks it navigated to GPS waypoints on its own, and its pod sampled temperature, conductivity and light at the bottom.

Open the V1 planner ↗

Visitors at the Creators' Showcase looking at V1
V2PrototypeSummer 2026

The prototype that taught us

V2 moved the brain to a Raspberry Pi 5 and prototyped stereo depth with YOLOv8 obstacle detection, a live web dashboard and our first custom PCB.

It was never fully built. Bench testing exposed flaws in its motor control, power and safety design, and those lessons led us to redesign the whole system.

Try the V2 command center ↗

Fiberglass over a printed V2 hull KiCad layout of the V2 PCB, REV 02
V3In buildFall 2026

Built for the field

A ground-up redesign that fixes what V2 got wrong: two Raspberry Pi Pico 2 real-time controllers, CAN-bus motor control, a fused and monitored 10S power system and a new RS-485 sensor pod, with a fish-finder sonar for depth. The carrier and pod boards are laid out and checked.

The goal: autonomous surface surveys of small bodies of water. Right now we're talking with the Charles River Watershed Association (CRWA) about data collection.

See the V3 system →

V3 carrier board render V3 pod board render
03 · What broke

The dead ends that shaped V3.

We'd rather show you what didn't work than pretend everything did.

Failed · V1

Jet drive

An early jet-propulsion experiment on V1 that didn't work out. A dead end, but a useful one: it taught us early what to keep simple.

Failed · V2 bench

V2's control, power and safety design

Bench testing showed that V2's motor control, power and safety design weren't reliable enough to put on the water.

Fix in V3Real-time control moved to two Raspberry Pi Pico 2s, each VESC became its own CAN node, every power feed got its own fuse and current monitor, and the winch driver got a fail-safe hardware kill, ready for the later sample-collection stage.

04 · Roadmap

Where it's going.

V3's goal is deliberately focused: drive itself around small bodies of water and collect data at the surface. Collecting physical samples comes later.

  1. V1 · Spring 2026V1

    Proof of concept

    Autonomous waypoint navigation, a 1 km radio link and bottom sampling, on a 3D-printed hull.

    Complete
  2. V2 · Summer 2026V2

    The prototype that taught us

    Pi 5, stereo vision and our first PCB. Never fully built; its flaws drove V3.

    Prototype
  3. V3 · Fall 2026 · NowV3

    Autonomous surface surveys

    V3 will drive itself around small bodies of water, sample at the surface with the pod and measure depth with a fish-finder sonar.

    In build
  4. LaterNext

    Sample collection

    A robotic arm on deck that works with the winch to collect water samples and sediment from the bottom.

    Arm in development

V3 milestones

  1. Done

    Electronics designed

    Carrier board (rev F), V3.1 starter board and sensor-pod board (rev B) laid out and checked.

  2. In progress

    New hull

    A modular hull in CAD, built around the V3 electronics.

  3. Next

    Build

    Fabricate the boards and assemble the electronics, pod and fish finder into the hull.

  4. Planned

    Firmware

    Autonomous waypoint navigation, surface sampling and depth logging, streamed to the dashboard.

  5. Planned

    Field trials

    Surveys of small bodies of water, shaped by our conversations with the CRWA.

Why sediment

In our conversations with the Port of Oakland and the Charles River Watershed Association, we learned that their teams still collect sediment samples by sending divers down. An arm on an autonomous boat could do that job without anyone going in the water.