Print files are emailed only after a sign-up form, are licensed for non-commercial use, and the full build relies on about $1,650 of Dynamixel servos.
A 16-motor, four-finger anthropomorphic robot hand from Carnegie Mellon University built from Dynamixel servos, off-the-shelf brackets and a few 3D-printed parts. A special knuckle joint lets each finger swing side to side in any bend pose. It is widely used in robot learning research, with Python, C++ and ROS APIs plus glove and Vision Pro teleoperation code.
At a glance
| Parts cost | $1,800 (2023) project · Stated by the project in August 2023. Servo prices have risen since, so a build now lands near $2,000 source ↗ |
|---|---|
| Difficulty | 2/5 Easy · Mostly bolting Dynamixels and stock brackets together with few printed parts, though motor horns must be set to their home position during assembly. |
| Build time | Under 3 hours (project-stated), plus under 24 hours of printing source ↗ |
| Tools needed | 3D printer (under 24 h of PLA; direct-drive extruder needed for the optional NinjaFlex fingertips), hex keys and PH00 screwdriver, soldering iron (for the optional DIY power cable) |
| Motors | 16 Dynamixel XC330-M288-T (full) or XL330-M288-T (Lite) servos with FPX330 brackets |
| Controller | PC via Dynamixel U2D2 USB interface, 5 V 30 A supply |
| Sensors | Servo position, velocity and current feedback only |
| Published | ✓ Parts list✓ CAD/STL✓ Assembly guide✓ Wiring✓ Software✗ Video Project website (parts, CAD, assembly pages) + GitHub API repo |
| Activity | Last update 2025-10-20 · 175 GitHub stars · 52 forks; questions by email; new tendon-driven LEAP Hand v2 variants announced |
| Kits | Robotis sells LEAP Hand Dynamixel bundles, and the project offers full parts kits by email |
Licenses
The design license is non-commercial. Building one for personal, educational or research use is allowed, but selling builds, parts or kits is not.
| Design files | CC BY-NC-SA (agreed to on the CAD request form) source ↗ |
|---|---|
| Code | MIT per README, but the repo's only LICENSE file is CC BY-NC 4.0 source ↗ |
| Documentation | None found for the website source ↗ |
Builder notes
Practical points from the project's issue tracker, forum and docs, each linked to its source.
- The parts table prices XC330 servos at $89.99 as of Aug 2023, but Robotis US now lists them at $103.39, so 16 motors alone come to about $1,650 and a full build lands near $2,000. source ↗
- The cheaper Lite version uses XL330 motors that builders report as less reliable, with overload faults at the default current limit. The maintainer suggests keeping Lite motors near 300 mA. source ↗
- With the stronger XC330 motors the example's conservative current limit can be raised to roughly 600 mA. There is no gravity compensation, so position error under finger weight is handled by tuning PID gains. source ↗
- Joint read rates around 30 Hz instead of the expected 90 Hz have been traced to the U2D2 and USB drivers on some PCs. Using sync reads and combined position/velocity/current queries helped. source ↗
- The 3D-print files are not in the repo and are only sent after filling out a name, email and organization form. source ↗
Other hands plans
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- RUKA hand · $1,300 · difficulty 3/5
- Aero Hand Open · $320 · difficulty 3/5
- ORCA Hand · $2,000 · difficulty 4/5
- YUBI glove and gripper (Toyota) · $550–$750 · difficulty 4/5
- Yale OpenHand (Model T42 / Model O) · $1,400 · difficulty 3/5
- DexHand (The Robot Studio) · $300 (2023) · difficulty 4/5