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OPENARM: A RESEARCH-GRADE FORCE-FEEDBACK ROBOT ARM

An open-hardware arm built for physical AI — backdrivable QDD actuators and true bilateral teleoperation, the kind of rig imitation-learning labs actually use.

by Enactic

FULL CAD BOM FIRMWARE DOCS

RoboticsAI

Built with3D printing

difficulty
●●●●●
time
a serious project
license
CERN-OHL-S-2.0 (hardware), Apache-2.0 (software)
repo
repo ACTIVE3,560 stars

WHAT YOU’LL NEED

Videos
1
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COMPAREE VERDICT

This is the serious one on our list — the arm you build when you've outgrown the cheap printed ones. Enactic open-sourced a research-grade platform for physical AI: backdrivable quasi-direct-drive actuators, true bilateral (leader-follower) teleoperation with force feedback, and a full stack — CAD, URDF, MuJoCo and Isaac Lab simulation, a CAN control library, ROS2, and teleop — spread across nine repos. The point is imitation learning where the robot can feel contact, not just replay positions. Two things to respect before you start: it's a big-ticket, expert-level build (band $$$), and the hardware is licensed CERN-OHL-S-2.0, not Apache — so read the license if you plan derivatives. For a lab, a serious hobbyist, or a research-minded team, it's outstanding.

GOOD TO KNOW

  • —CAD (STL/STEP/Fusion) plus URDF, MuJoCo and Isaac Lab sim, CAN control, ROS2, teleop across 9 repos
  • —Hardware license is CERN-OHL-S-2.0 (not Apache) — software repos are Apache-2.0; matters for derivatives
  • —BOM is on Google Drive alongside the CAD
  • —This is research-grade, not a weekend build

Parts to buy

4 items

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

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Can I build this?

Printstructural parts (STL); STEP/Fusion for editing
BuyDAMIAO QDD actuators (8 per arm), a CAN interface, compute, fasteners
Toolsprecision assembly, CAN debugging, ROS2 environment
Skillsexpert: robotics, ROS2, control, force-feedback tuning
Timea serious multi-week project
Costband $$$ — about 6,500 dollars for a complete bimanual system according to the project; assembled and DIY kits are sold through certified manufacturers
Safetypowerful actuators — respect the workspace; motors are backdrivable but can move fast

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

Videos

OpenArm 01 | Open-source humanoid arm for physical AI1:22

Short official intro from Enactic — the docs are the real reference.

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Gallery

OpenArm with its data-collection cellEnactic
Introducing OpenArm v2Enactic
CAD of the collection cellEnactic
Bilateral teleoperation in useEnactic

Start here

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

  1. 1.Read the docs (start here — the full reference)
  2. 2.Watch the intro (90 sec overview)
  3. 3.Explore the repos (hardware, description, can, ros2, teleop, sim)
  4. 4.Read the purchase/BOM guide (actuators + parts)
  5. 5.Join the Discord (the OpenArm community)

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

  • Hardware is CERN-OHL-S-2.0, not Apache — read it before building derivatives
  • It's spread across nine repos plus a Google Drive BOM — expect to piece the picture together
  • DAMIAO actuators dominate the cost and the difficulty — this is expert-level

What makes it different from a cheap printed arm?

Force feedback. The backdrivable QDD actuators and bilateral teleoperation let the arm feel contact, which is what serious imitation-learning setups need — not just position replay.

Can a hobbyist build it?

An experienced one, yes — but it's expert-level and expensive. If you're starting out, build SO-ARM100 first and come back to this.

What sim tools does it support?

MuJoCo and Isaac Lab, with URDF/xacro descriptions and a CAN control library plus ROS2.

What does it cost?

About 6,500 dollars for a complete bimanual system, according to the project. Assembled and DIY kits are sold through certified manufacturers listed on the docs' purchase page, and the BOM is in the project's Google Drive.

Community builds

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

Discussion1

FROM THE COMPAREE TEAM

OpenArm's whole argument is force feedback — backdrivable actuators that feel contact instead of blindly replaying positions. How much does that actually matter for imitation learning, in your experience?

CompareeTEAM2mo agoedited

Practical notes from our verification: OpenArm is a 7-DOF arm spread across nine repositories. The hardware CAD is CERN-OHL-S-2.0, a strongly reciprocal licence, while the software (description, CAN library for Damiao motors, ROS2, teleop, Isaac Lab, MuJoCo, dataset tools) is Apache-2.0. The hardware files and BOM live on Google Drive, which the project calls the source of truth; GitHub releases are only mirrors. The project quotes about 6,500 dollars for a complete bimanual system, and certified manufacturers sell assembled and DIY units. 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.

3D print this robot arm, show it a task, and it learns to repeat it

●●●○○ · start here — the cheap, printable arm before this one

ALOHA: The Stanford Robot That Learns From You

●●●●○ · another bimanual teleoperation platform, built on commercial arms

Amazing Hand: A Fully 3D-Printed Robotic Hand

●●●○○ · a dexterous printed hand to pair with an arm

Enactic

A robotics company open-sourcing a research-grade arm for physical AI — force-feedback teleoperation and a full sim-to-real stack — to make state-of-the-art results reproducible.

GitHub Web

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