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PEOPLE CONTROL ROBOT ARMS WITH THEIR BRAINWAVES USING THIS 3D-PRINTED HEADSET

A 3D-printed headset that reads your brainwaves and turns them into commands that move robotic hands, drones, or cursors — no surgery, no implant.

by OpenBCI (Conor Russomanno, Joel Murphy, and community)

FULL CAD BOM FIRMWARE DOCS

Open-hardwareScience

Built with3D printing

difficulty
●●●●○
time
several weekends
license
MIT
repo
repo ACTIVE961 stars

WHAT YOU’LL NEED

1
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COMPAREE VERDICT

OpenBCI is the real thing: a non-invasive brain-computer interface you can build at home. The Ultracortex headset is 3D-printed, the electrodes sit on your scalp, and the biosensing board (Cyton or Ganglion, bought from OpenBCI) reads the tiny electrical signals your brain and muscles produce. The open-source GUI turns those signals into commands, and people have used it to move robotic arms, fly drones, and control cursors. The wow is that it works and it is fully open. The hard part is getting reliable control — EEG signals are noisy, electrode placement matters, and you will spend real time on signal processing and calibration before you get a clean command. This is not plug-and-play; it is a research-grade tool that happens to be open source. If you want to explore BCIs without waiting for a consumer product or a lab, this is the project. If you want a weekend demo that just works, you will be disappointed. The single thing most likely to go wrong: expecting consistent control on day one. Budget time for learning the signal chain, not just printing the headset.

GOOD TO KNOW

  • —The Ultracortex frame is open hardware (STL/STEP files on GitHub, guide on docs.openbci.com); the Mark IV electrodes and electrode holders are bought, not printed.
  • —The Cyton or Ganglion biosensing board is bought from OpenBCI — you do not solder it from scratch.
  • —GUI software is MIT-licensed and cross-platform (Windows/Mac/Linux).
  • —Getting reliable control takes real work — signal processing, electrode placement, and a lot of calibration.
  • —Not a medical device; community-supported, not a polished consumer product.
  • —Licence is MIT for the GUI software and GPL-3.0 for the Ultracortex headset files — commercial use is allowed under those terms.

Parts to buy

4 items

From our check of the build. Exact quantities and part numbers are in the creator’s BOM.

  • Cyton or Ganglion biosensing board from OpenBCIFind
  • Non-printed Mark IV parts: dry spiky electrode unitsFind
  • Comfort unitsFind
  • Ribbon cables and screwsFind

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Can I build this?

PrintUltracortex Mark IV headset frame and electrode mounts (several prints, PLA or PETG)
BuyCyton (8 channels) or Ganglion (4 channels) biosensing board from OpenBCI, plus the non-printed Mark IV parts: dry spiky electrode units, comfort units, ribbon cables and screws (sold by OpenBCI as the Print-it-Yourself kit)
Tools3D printer, soldering iron for board headers, computer running Windows/Mac/Linux for the GUI, optional oscope or multimeter for signal debugging
SkillsIntermediate 3D printing, basic soldering, comfort with signal processing concepts — the GUI is approachable but getting clean signals requires patience and iteration
TimeA weekend to print and assemble the headset, then several sessions to calibrate and get reliable control — real BCI work, not a quick demo
Cost$$$ — the biosensing board is the bulk (Cyton about 1,250 dollars, Ganglion about 625 dollars from OpenBCI); printing the headset and buying electrodes adds more on top
SafetyNone beyond ordinary electronics care — non-invasive, low voltage signals only. Not a medical device, do not use for diagnosis or treatment.

Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.

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Gallery

Start here

Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.

  1. 1.Decide which biosensing board to buy — Cyton (8 channels, more expensive, more research-grade) or Ganglion (4 channels, cheaper, still capable).(The board is not built from scratch; you buy it assembled from OpenBCI (Cyton about 1,250 dollars, Ganglion about 625 dollars).)
  2. 2.Print the Ultracortex Mark IV frame halves, board mount, board cover and wire clips (files in the GitHub repo and the Mark IV guide). (The repo holds the STL and STEP files; the parts list and step-by-step assembly are in the Mark IV guide on docs.openbci.com. Print each frame half flat side down, with support and a brim or raft, and pick the frame size that fits your head.)
  3. 3.Order the dry electrode units (spiky electrodes and comfort nodes) and ribbon cables listed in the Mark IV guide.(Cheap electrodes give noisy signals; the BOM specifies tested parts.)
  4. 4.Download and install the OpenBCI GUI on your computer. (Cross-platform, well-documented, and actively maintained.)
  5. 5.Assemble the headset, connect the board, and start with the GUI's impedance check to verify electrode contact.(Good contact is everything; expect to iterate on electrode placement and how far each electrode is screwed in.)

Resources

Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.

KNOWN ISSUES

  • Buying the wrong board for your use case — Ganglion is cheaper but has fewer channels; if you want to explore motor imagery or serious signal work, Cyton is the better start.
  • Expecting clean control on day one — EEG signals are tiny (microvolts) and noisy, and getting a reliable command takes real calibration time.
  • Expecting dry electrodes to work through hair without adjustment. The Mark IV uses dry spiky electrodes; each one has to be screwed in until it touches the scalp firmly, and contact quality varies with hair. Use the GUI's impedance check before trusting a signal.
  • Printing the headset without checking fit — the frame needs to hold electrodes snugly against your scalp, and head sizes vary; test fit early.
  • Not budgeting time to learn the signal chain — the GUI is approachable, but understanding FFT, bandpass filters, and artefact rejection is part of the work if you want robust control.
  • Treating it like a consumer product — this is a research tool with community support, not a polished kit; expect to read docs and ask questions.

Do I build the biosensing board from scratch?

Usually not — most people buy the Cyton or Ganglion as a finished board from OpenBCI. The board designs are open (schematics and PCB files are published), so building your own is possible, but it is a fine-pitch SMD job.

Can I actually control things reliably, or is this a demo?

Both — people have used it for real control (moving robotic hands, flying drones, cursor control), but getting there takes work. Signal quality depends on electrode placement, your environment, and calibration. It is not plug-and-play.

What is the difference between Cyton and Ganglion?

Cyton has 8 channels and better specs (higher sample rate, more research-grade); Ganglion has 4 channels and costs less. Ganglion is enough for basic BCI experiments; Cyton is better if you want to go deep.

Is this safe to use?

Yes — it is non-invasive, reads signals from your scalp, and operates at low voltages. It is not a medical device and should not be used for diagnosis or treatment.

What can I control with it?

Anything that accepts serial or OSC commands — robotic arms, drones, games, cursors. The GUI has examples and integrations, but you will likely need to write or adapt code for your specific use case.

Community builds

No community builds yet — be the first, we feature the best ones.

Discussion1

FROM THE COMPAREE TEAM

The hardest part is not printing the headset or buying the board — it is getting clean, consistent signals through the noise. What would you try to control first, and how much calibration time would you budget before expecting it to work reliably?

CompareeTEAM2mo agoedited

Practical notes from our verification: the Ultracortex repository has STL files for every headset generation, with Mark IV (2017) as the current one, and is licensed GPL-3.0; the OpenBCI GUI is MIT-licensed, actively maintained and runs on Windows, macOS and Linux. Most people buy the Cyton or Ganglion biosensing board from OpenBCI rather than building it, but the boards are open hardware too, with schematics, PCB files and BOMs published. The Mark IV headset uses dry spiky electrodes and comfort nodes in the printed frame, so print quality and fit on your head matter. The single biggest thing to know before starting: this is not a weekend demo kit. It is a research-grade tool, and getting reliable control from EEG takes real time on signal processing and electrode placement. If you are comfortable with that, it is one of the most accessible open BCI platforms available. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.

OpenBCI (Conor Russomanno, Joel Murphy, and community)

OpenBCI started as a Kickstarter in 2013 to make brain-computer interfaces accessible outside labs. The project grew into a full platform — biosensing boards, open-source software, and a printed headset — all designed to let people explore BCIs without waiting for consumer products or research budgets.

GitHub

Star the project on GitHub

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  • Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
  • Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
GitHub repo