Printing the links saves little, since the five Dynamixel XM430 servos alone cost well over 1,000 USD.
OpenMANIPULATOR-X (RM-X52-TNM) is a small 4-DOF arm with a gripper from ROBOTIS, built from five Dynamixel XM430 smart servos and mostly 3D-printable links. It is aimed at ROS education and pairs with the TurtleBot3 platform, with ROS 2 packages and LeRobot-style leader/follower support. ROBOTIS sells it as a kit, and the plastic parts are published for printing.
At a glance
| Parts cost | $1,600 kit · ROBOTIS US kit price, covering the 5 servos, frames and cables but not the controller, U2D2 adapter or power supply source ↗ |
|---|---|
| Difficulty | 2/5 Easy · Bolt-together assembly of smart servos with a detailed manual. The hard part is the price, not the build. |
| Build time | Not stated |
| Tools needed | 3D printer (optional, small parts) or ROBOTIS frame set, small screwdrivers and hex wrenches (included with kit) |
| Motors | 5 Dynamixel XM430-W350-T servos |
| Controller | OpenCR board or a PC through a U2D2 interface, 12V supply |
| Sensors | Servo position feedback only |
| Published | ✓ Parts list✓ CAD/STL✓ Assembly guide✗ Wiring✓ Software✓ Video ROBOTIS e-Manual website + assembly PDF + Onshape/Thingiverse CAD + YouTube |
| Activity | Last update 2026-10-01 · 668 GitHub stars · 235 forks, ROBOTIS forum and GitHub issues |
| Kits | Sold by ROBOTIS and resellers (about 1,416 to 1,629 USD); RM-X52 frame set without servos is 273.70 USD |
Licenses
| Design files | CC BY 4.0 for the printable parts on Thingiverse; described as open source hardware on the e-Manual; metal FR12 frames and servos are proprietary ROBOTIS parts source ↗ |
|---|---|
| Code | Apache-2.0 source ↗ |
| Documentation | None found on the OpenMANIPULATOR-X pages (the e-Manual source repo is MIT) source ↗ |
Builder notes
Practical points from the project's issue tracker, forum and docs, each linked to its source.
- The printed parts are free, but the 5 XM430 servos make up most of the cost. ROBOTIS's frame-only set (no servos, controller or supply) is 273.70 USD. source ↗
- With only 4 arm joints, MoveIt's default IK cannot solve many poses. Users built an IKFast plugin or set position-only IK, and ROBOTIS did not ship a dedicated 4-DOF solver. source ↗
- After the 2025 ROS 2 rewrite, some users hit Dynamixel sync read failures when following the quick start, usually traced to communication settings. source ↗
- The repo now covers both OMX and the larger OMY arm and adds leader/follower teleoperation for imitation learning. source ↗
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