SO-101 arm
The Robot StudioSO-101 is a low-cost, 3D-printable six-degree-of-freedom robot arm designed by The Robot Studio with Hugging Face, sold as a leader and follower pair for teleoperated data collection with the LeRobot library. The repository publishes STEP and STL files for every part, and a two-arm kit costs about $230 in parts or ships ready-made from several vendors.
The same repository also carries the previous generation, SO-100, which is not a separate entry.
Openness
5 high confidence- form_factor
- board(a complete robot arm, sold as a kit or printed from the design)
- schematics
- open(STEP and STL for every part under Apache-2.0)
- toolchain
- open(driven by the Apache-2.0 LeRobot library)
- retail
- open_market(kits from several vendors)
Every printed part is published as STEP and STL under Apache-2.0, the arm is set up and driven through the open LeRobot library, and kits are on open sale. The Feetech servos inside are off-the-shelf parts with their own closed firmware.
- https://huggingface.co/docs/lerobot/main/en/assemble_so101 recorded 2026-09-27
LeRobot assembly guide: "our flagship robot, the SO-101"; "The follower arm uses 6x STS3215 motors with 1/345 gearing"; joints Base / Shoulder Yaw, Shoulder Pitch, Elbow, Wrist Roll, Wrist Pitch, Gripper.
- https://raw.githubusercontent.com/TheRobotStudio/SO-ARM100/main/LICENSE recorded 2026-09-26
LICENSE: the Apache License, Version 2.0 text, covering the repository.
- https://raw.githubusercontent.com/TheRobotStudio/SO-ARM100/main/README.md recorded 2026-09-26
README: "designed to work seamlessly with the open-source LeRobot library"; kits from Seeed Studio, Taobao, Akizuki Denshi and AliExpress; Feetech's own software is for debugging and "not necessary as motors can be configured using the LeRobot Library".
- https://ungh.cc/repos/TheRobotStudio/SO-ARM100/files/main recorded 2026-09-26
Repository tree: STEP/SO101/SO101 Assembly.step, STEP/SO101/Base_SO101.step, STL/SO101/Individual/*.stl, Simulation/SO101 assets.
Adoption
2 low confidenceGitHub stars on the design repository. Kits are sold by several independent vendors, none of which publishes volumes.
- https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/TheRobotStudio%2FSO-ARM100 recorded 2026-09-26
Repository record for TheRobotStudio/SO-ARM100: 7,401 stargazers.
Capability
2 high confidenceSO-101 is a single small arm with six joints, and its leader arm is only a teleoperation controller, so on its own it does single-arm tabletop tasks. Pairing two, or mounting one on a mobile base, is a separate build.
- https://huggingface.co/docs/lerobot/main/en/assemble_so101 recorded 2026-09-27
LeRobot assembly guide: "our flagship robot, the SO-101"; "The follower arm uses 6x STS3215 motors with 1/345 gearing"; joints Base / Shoulder Yaw, Shoulder Pitch, Elbow, Wrist Roll, Wrist Pitch, Gripper.
- https://raw.githubusercontent.com/TheRobotStudio/SO-ARM100/main/README.md recorded 2026-09-26
README: two-arm (leader and follower) kit bill of materials.
Verified 2026-09-26