The official parts are laser-cut acrylic, so builders without a cutter need a cutting service or a 3D-print remix.
MeArm is a pocket-sized 4-axis arm made from flat laser-cut 3 mm acrylic and four micro servos, designed in 2014 to be a cheap entry point into robotics. It has been copied widely, and controller code exists for Arduino, Raspberry Pi, micro:bit and other boards. The design is OSHWA-certified open hardware.
At a glance
| Parts cost | $40 kit · Price of MeArm's cut-your-own maker kit (32.99 GBP), which has the servos, circuit board and fixings but not the acrylic or a controller source ↗ |
|---|---|
| Difficulty | 1/5 Beginner · Flat-pack acrylic and four servos, built with a hex key in under two hours. |
| Build time | About 2 hours for v1, about 40 minutes for v3 source ↗ |
| Tools needed | Laser cutter for 3 mm acrylic (or a 3D-printed remix), hex key and small screwdriver |
| Motors | 4 MG90-size micro servos |
| Controller | Arduino, Raspberry Pi, micro:bit or ESP boards via MeArm controller PCBs |
| Sensors | None |
| Published | ✗ Parts list✓ CAD/STL✓ Assembly guide✗ Wiring✓ Software✓ Video GitHub (DXF cut files, KiCad PCB, assembly PDFs for v1 and v3) + YouTube build video + Thingiverse |
| Activity | Last update 2026-07-03 · 214 GitHub stars · 72 forks, very large number of clones and Thingiverse remixes |
| Kits | MeArm Ltd sells maker kits and controller boards |
Licenses
| Design files | CC BY-SA 4.0 (OSHWA UK000047; Thingiverse listing also CC BY-SA 4.0) source ↗ |
|---|---|
| Code | CC BY-SA 4.0 per OSHWA certification UK000047 (controller libraries live in separate MeArm repos) source ↗ |
| Documentation | CC BY-SA 4.0 (OSHWA UK000047) source ↗ |
Builder notes
Practical points from the project's issue tracker, forum and docs, each linked to its source.
- The repo has no parts list. The maintainer confirmed 3 mm acrylic, M3 fixings for v1, M2.5 for v2 and v3, and four MG90-size servos. source ↗
- SG90 servos fit but their plastic gears tend to strip, so metal-gear MG90s are the better choice. source ↗
- v1 needs no PCB, while v2 and v3 expect a MeArm controller board in the base, and v2 also needs elastic bands or O-rings. source ↗
- Servos must be calibrated to set positions before assembly, or parts of the arm have to come apart again later. source ↗
Other arms plans
- SO-101 arm · $230 · difficulty 2/5
- EEZYbotARM MK2 · $100 (2018) · difficulty 2/5
- GELLO teleoperation arms · $280 (2023) · difficulty 2/5
- Thor arm · $390 · difficulty 4/5
- reBot-DevArm (Seeed Studio) · $1,500 · difficulty 4/5
- OpenArm · $6,500 · difficulty 5/5
- Koch v1.1 arm · $480 (2024) · difficulty 2/5
- ROBOTIS OpenMANIPULATOR-X · $1,600 · difficulty 2/5
- BCN3D Moveo · $430 · difficulty 4/5
- PAROL6 · $970 · difficulty 4/5
- Faze4 robotic arm · $1,000–$1,500 (2020) · difficulty 4/5