~$230 DIY parts (pair); kits $199 – $419Official BOM totals ~$230 in the US for a leader + follower pair (~$122 for one follower). Assembled pairs from vendors such as WowRobo list at $299; Hiwonder sells assembled kits from $389.99.
AvailablePython from a laptopLeRobot nativeLeader–follower teleop3D printedApache-2.0
Possibly ≤ 1 weekShipping: ~1 week from China; US vendors faster. US vendors (PartaBot, ForgeMotion Labs, Amazon listings) sell kits and assembled pairs; WowRobo ships from China by UPS/DHL with duties prepaid (2–5 business days after 1–3 days prep). Kit vendors list ↗
Remote control: Plugs into a laptop over USB; the
lerobot Python library calibrates it, teleoperates it from the leader arm, records datasets and runs trained policies (training also works on Apple Silicon via mps).Overview
The default arm of the LeRobot imitation-learning ecosystem and the cheapest serious entry point into end-to-end robot learning. It is a 3D-printed follower plus a leader arm for teleoperation, built from 12 Feetech STS3215 servos. The 2025 revision of the SO-100 improved wiring, removed the need to strip gears for assembly and changed leader-arm motor gearing. Precision and payload are toy-grade, but thousands of community datasets and pretrained policies target exactly this arm.
The default choice for learning imitation learning on a budget.
Specifications
| Category | Robot arms · Desktop & hobby arms |
|---|---|
| Released | 2025 |
| Availability | Available |
| Programmability | Open source (hardware + software) |
| Best for | Ages 14+ (estimated) |
| Vision sensors | No vision sensors |
| Actuators | Smart servos (Dynamixel, Feetech…) |
| Audio | No audio |
| Compute type | Laptop / PC as the brain |
| Remote control | Python from a laptop |
| DOF | 6 (5 joints + gripper) |
| Reach | Not published |
| Payload | Not published (light objects only) |
| Repeatability | Not published |
| Weight | Not published |
| Controller | None on the arm; Waveshare serial bus-servo board to a host PC over USB |
| Sensors | Servo position/load feedback from Feetech STS3215 bus servos; USB cameras added by the user (wrist/overhead mounts in the repo) |
| SDK | Hugging Face lerobot (Python): calibration, teleop, dataset recording, policy training (ACT, diffusion, SmolVLA, etc.) |
Ratings & reviews
Ratings and reviews load on the live site.
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