Open source Humanoids
Berkeley Humanoid Lite
An open-source, mid-size humanoid from UC Berkeley’s Hybrid Robotics lab: 22 DoF, 3D-printed cycloidal actuators and off-the-shelf parts, for about US$4,350 in materials.
- Type
- Humanoid
- DoF
- 22
- Height
- 0.8 m
- Weight
- 16 kg
- BOM cost
- ≈ US$4,350.59
- Structure
- PLA prints + aluminium extrusion
- Open hardware and open code
- Full bill of materials with supplier links
- Direct links to the original CAD, code and papers
01 — Project details
Overview, BOM and resources
Overview
Berkeley Humanoid Lite (BHL) comes from Koushil Sreenath’s group with one goal: a mid-size humanoid that people can actually afford and build. Its heart is a modular 3D-printed cycloidal actuator — motors, drivers and bearings are commodity parts, and housings and gearboxes print on a desktop printer.
Walking policies are trained with reinforcement learning in simulation and transfer zero-shot to the real robot. Hardware, embedded code, training and deployment frameworks are all open, plus VR teleoperation.
Key specifications
| Actuators | 10 × 6512 (MAD M6C12 150KV) + 12 × 5010 (MAD 5010 110KV), 3D-printed cycloidal reduction |
|---|---|
| Motor drivers | ST B-G431B-ESC1 per joint, AS5600 magnetic encoder |
| Bus | CAN 2.0 at 1 Mbps via 4 USB-CAN adapters |
| Computer / IMU | Intel N95 mini PC, BNO085 |
| Battery | 6S 4000 mAh LiPo |
| Actuator cost | 6512 ≈ $188, 5010 ≈ $136 (paper) |
Bill of materials
Total US$4,350.59 (official sheet; China sourcing ¥23,244.19). Actuator prices already include their parts; the per-actuator breakdown is in the collapsible table below and is not double-counted.
Download the BOM (.xlsx) · Official BOM ↗
| Part | Model / spec | Qty | Unit | Subtotal | Supplier |
|---|---|---|---|---|---|
| Humanoid | |||||
| Mini PC | 1 | $129.00 | $129.00 | amazon.com ↗ | |
| LiPo battery 6S | 1 | $70.20 | $70.20 | amazon.com ↗ | |
| USB-CAN adapter | 4 | $16.99 | $67.96 | amazon.com ↗ | |
| USB hub | 2 | $17.99 | $35.98 | amazon.com ↗ | |
| BNO085 | IMU sensor | 1 | $12.76 | $12.76 | amazon.com ↗ |
| Aluminum extrusion 250 mm | 2 | $4.25 | $8.50 | amazon.com ↗ | |
| Aluminum extrusion 200 mm | 4 | $3.75 | $15.00 | amazon.com ↗ | |
| Aluminum extrusion 150 mm | 2 | $3.00 | $6.00 | amazon.com ↗ | |
| Aluminum extrusion 100 mm | 3 | $3.25 | $9.75 | amazon.com ↗ | |
| Aluminum inner bracket | 24 | $0.65 | $15.60 | amazon.com ↗ | |
| 24V to 12V regulator | 1 | $16.99 | $16.99 | amazon.com ↗ | |
| 12V to 5V regulator | 1 | $4.49 | $4.49 | amazon.com ↗ | |
| Voltage monitor | 1 | $14.99 | $14.99 | amazon.com ↗ | |
| Current monitor | 1 | $20.98 | $20.98 | amazon.com ↗ | |
| Circuit breaker | 1 | $19.99 | $19.99 | amazon.com ↗ | |
| Misc | Fasteners | 1 | $40.00 | $40.00 | |
| Misc | Cables & connectors | 1 | $50.00 | $50.00 | |
| M6C12 actuators | 8 | $188.69 | $1,509.51 | ||
| 5010 actuators | 4 | $136.36 | $545.44 | ||
| 3D print filament | 1 | $100.00 | $100.00 | ||
| 6803-2RS | Bearing between the linkage on the pitch actuators on legs | 6 | $2.87 | $17.22 | amazon.com ↗ |
| M6C12 actuators | 2 | $188.69 | $377.38 | ||
| 5010 actuators | 8 | $136.36 | $1,090.87 | ||
| Servo motor claw | 2 | $35.99 | $71.98 | amazon.com ↗ | |
| 3D print filament | 1 | $100.00 | $100.00 | ||
| Total | $4,350.59 | ||||
Per-actuator breakdown and alternatives (not double-counted)
| Part | Model / spec | Qty | Unit | Subtotal | Supplier |
|---|---|---|---|---|---|
| M6C12 Actuator | |||||
| MR106-2RS | Bearing between input shaft and cycloidal disk, and between input shaft and output shaft | 13 | $0.87 | $11.31 | amazon.com ↗ |
| 6701-2RS | Bearing between cycloidal disk and output shaft | 2 | $0.94 | $1.88 | amazon.com ↗ |
| 6811ZZ | Bearing between output shaft and housing | 2 | $5.00 | $10.00 | amazon.com ↗ |
| M3 x 55 mm | Mounting housing | 8 | $0.26 | $2.08 | amazon.com ↗ |
| M3 x 30 mm | Mounting output shaft | 6 | $0.19 | $1.14 | amazon.com ↗ |
| M2 x 3 x 3.5 mm | M2 threaded insert for mounting encoder | 4 | $0.07 | $0.28 | amazon.com ↗ |
| M3 x 4 x 5 mm insert | M3 threaded insert | 24 | $0.08 | $1.92 | amazon.com ↗ |
| M4 x 15 mm hex stand | input shaft stiffener | 1 | $0.69 | $0.69 | amazon.com ↗ |
| MAD Components M6C12 150KV | 1 | $129.00 | $129.00 | amazon.com ↗ | |
| PLA | 3D print filament, in kg | 0.12 | $25.99 | $3.12 | amazon.com ↗ |
| B-G431B-ESC1 | Motor controller | 1 | $18.97 | $18.97 | digikey.com ↗ |
| AS5600 | I2C position encoder | 1 | $3.30 | $3.30 | amazon.com ↗ |
| Misc | Cables & connectors | 1 | $5.00 | $5.00 | |
| 5010 Actuator | |||||
| MR106-2RS | Bearing between input shaft and cycloidal disk, and between input shaft and output shaft | 13 | $0.87 | $11.31 | amazon.com ↗ |
| 6701-2RS | Bearing between cycloidal disk and output shaft | 2 | $0.94 | $1.88 | amazon.com ↗ |
| 6809ZZ | Bearing between output shaft and housing | 2 | $2.26 | $4.52 | amazon.com ↗ |
| M3 x 55 mm | Mounting housing | 4 | $0.26 | $1.04 | amazon.com ↗ |
| M3 x 25 mm | Mounting output shaft | 6 | $0.19 | $1.14 | amazon.com ↗ |
| M2 x 3 x 3.5 mm | M2 threaded insert for mounting encoder | 4 | $0.07 | $0.28 | amazon.com ↗ |
| M3 x 4 x 5 mm insert | M3 threaded insert | 24 | $0.08 | $1.92 | amazon.com ↗ |
| M4 x 12 mm hex stand | input shaft stiffener | 1 | $0.40 | $0.40 | amazon.com ↗ |
| MAD Components 5010 110KV | 1 | $84.00 | $84.00 | amazon.com ↗ | |
| PLA | 3D print filament, in kg | 0.1 | $25.99 | $2.60 | amazon.com ↗ |
| B-G431B-ESC1 | Motor controller | 1 | $18.97 | $18.97 | digikey.com ↗ |
| AS5600 | I2C position encoder | 1 | $3.30 | $3.30 | amazon.com ↗ |
| Misc | Cables & connectors | 1 | $5.00 | $5.00 | |
| Humanoid | |||||
| IM10A | Alternative IMU sensor, easier to wire | 1 | $89.99 | $89.99 | hiwonder.com ↗ |
| Total | $4,350.59 | ||||
3D printing & fabrication
- Standard PLA (e.g. Bambu PLA Basic); about 0.12 kg per 6512 actuator and 0.10 kg per 5010.
- Settings are tuned for a Bambu Lab X1C with two profiles — actuator housing and actuator shaft; other structural parts can print faster, mirrored along X for left/right.
- Brass hex standoffs stiffen the input shaft and M3×55 through-bolts prevent layer splitting; the torso uses aluminium extrusion.
- Sliced .3mf projects are on Bambu MakerWorld (sign-in required).
CAD, code & papers
Get the large files — CAD, STL, STEP and code — straight from the original project:
- Project website ↗lite.berkeley-humanoid.org
- GitHub (main) ↗github.com
- Robot description (URDF / MJCF / USD) ↗github.com
- Low-level control code ↗github.com
- Motor controller firmware ↗github.com
- Full-robot CAD (Onshape) ↗cad.onshape.com
- 3D print files (MakerWorld) ↗makerworld.com
- Documentation (GitBook) ↗berkeley-humanoid-lite.gitbook.io
- Paper arXiv:2504.17249 ↗arxiv.org
- Official BOM (Google Sheets) ↗docs.google.com
- Demo video ↗youtube.com
License
Code MIT; CAD, docs and other assets CC BY-SA 4.0.
Image credits
- Image 1: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · CC BY-SA 4.0 — source ↗
- Image 2: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · © paper authors — source ↗
- Image 3: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · CC BY-SA 4.0 — source ↗
- Image 4: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · CC BY-SA 4.0 — source ↗
- Image 5: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · © paper authors — source ↗
- Image 6: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · © paper authors — source ↗
- Image 7: Berkeley Humanoid Lite Project (UC Berkeley Hybrid Robotics) · © paper authors — source ↗
Source: Images and data: UC Berkeley Hybrid Robotics (Berkeley Humanoid Lite website, GitHub and RSS 2025 paper). Code MIT, other assets CC BY-SA 4.0. This site is not affiliated with the original project.
Get the parts
Where to get the parts
Every line in the BOM links to the supplier the original team used. Need help sourcing parts or 3D-printing the structure? Tell us which robot you are building.
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