AMAZING HAND: A FULLY 3D-PRINTED ROBOTIC HAND
A tendon-free, fully printable four-finger robot hand — 8 degrees of freedom, light in the hand, and open-sourced by the team now inside HuggingFace.
by Pollen Robotics (HuggingFace)
Robotics3D-printing
- difficulty
- ●●●○○
- time
- a weekend or two
- license
- Apache-2.0
- repo
- repo ACTIVE2,259 stars
●●●○○ · a weekend or two · Apache-2.0 · 2,259 stars · repo ACTIVE
WHAT YOU’LL NEED
- 3D printer + filament — printable parts — files are in the repo
- Dev board / microcontroller — runs the project firmware
- Soldering kit + basic tools — one-time buy, serves every future build
Partner
COMPAREE VERDICT
This is the printable robot hand we'd actually recommend building. Pollen Robotics — now part of HuggingFace — open-sourced a four-finger, two-phalanx hand with eight degrees of freedom that's genuinely light in the hand. The clever part is the mechanism: no cables or tendons to route and tension, just two small servos per finger driving a ball-joint linkage, with rigid bones and flexible TPU pads. Everything's there: STL and editable STEP, a Python/Arduino control stack, even webcam hand-tracking. The one gap to know about is the BOM, which lives in an external Google Sheet rather than the repo. For a dexterous, satisfying, non-marathon build, it's a standout.
IN THE REPO
NOT IN THE REPO
- —cad/ folder has STL and editable STEP; control code in Python + Arduino
- —No cable/tendon routing — two servos per finger via a ball-joint linkage
- —BOM is an external Google Sheet, not a file in the repo
- —Hardware is CC BY 4.0; code is Apache-2.0
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Partner · KickstarterHeyGears G1: 10M+ colors and transparent parts in one print, plus UV printing on flat objects. Figures, parts and labels — no painting.
Videos
AH! (Amazing Hand!) demo0:28
The creator's demo, linked from the README.
Gallery
Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Read the blog post (the official writeup)
- 2.Watch the demo (see it move)
- 3.Open the CAD (STL + STEP in cad/)
- 4.Get the BOM sheet (external Google Sheet, linked in the README)
- 5.Flash the control code (Python + Arduino)
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
- The BOM is an external Google Sheet, not a file in the repo — find it via the README
- Print the bones rigid and the pads in TPU — mixing that up ruins the grip
- Hardware is CC BY 4.0 and code is Apache-2.0 — mind the split if you remix
Does it use tendons?
No — that's the clever bit. Two servos per finger drive a ball-joint linkage, so there are no cables to route and tension. Eight degrees of freedom total.
Is it heavy?
No — it's designed to be light in the hand, which is why it suits humanoid platforms like Reachy.
Can I buy the servos as a kit?
Not from the repo, but kits are sold via Seeed Studio and WowRobo. The BOM sheet lists the parts.
What does it cost?
Band $$ — the servos are the main line item. The BOM sheet has current prices.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
Pollen ditched tendons entirely — two servos per finger through a ball-joint linkage. Do tendon-free hands trade away too much dexterity, or is the simplicity worth it?
SO-ARM100: The Low-Cost Robot Arm Behind HuggingFace LeRobot
●●●○○ · an arm to mount your hand on
OpenArm: A Research-Grade Force-Feedback Robot Arm
●●●●● · a research-grade arm for the same pairing
ALOHA: The Stanford Robot That Learns From You
●●●●○ · if you want grippers-plus-learning instead of a hand
Pollen Robotics (HuggingFace)
The team behind the Reachy robot — now part of HuggingFace — open-sourced a light, tendon-free printable hand that simplifies a research-grade design for everyone.
DISCLAIMER
- Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
- 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.


CompareeTEAM1mo ago
While reading the fine print we noticed the licensing is split: the hardware is CC BY 4.0 while the code is Apache-2.0, which matters if you plan to remix it. There's also a practical print trap — the bones need to be rigid and the pads TPU, and mixing that up ruins the grip. Has anyone mounted one of these on a robot arm yet?