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Berkeley Humanoid Lite: where a USD 5,000 humanoid spends its money and your hours

A 3D-printed humanoid with every engineering file public. Alongside LeRobot Humanoid it represents the other route: buy finished joint motors, or print your own cycloidal gearboxes.

Total cost: About USD 5,000 (paper figure)
Structure: 3D-printed body; joints = printed cycloidal gearboxes + brushless motors
Engineering files: Structure, electronics, firmware and control stack all published
Power: Brushless motors + CAN (same family of thinking as LeRobot Humanoid)
Print time: Weeks (many parts, mostly load-bearing)
Project: berkeleyhumanoid.com

Files you actually get: The biggest difference from LeRobot Humanoid is editability: this release starts from engineering sources — structure, electronics, firmware and control stack. Lengthening a leg, swapping a motor or adding a mounting face happens in the original CAD, not by reverse-engineering a mesh. The price is guidance: the documentation is less scripted than LeRobot's, and more of the path means reading code and fighting environments yourself.
BOM and delivered cost: About USD 5,000. The premium over LeRobot Humanoid is not the motors — same-family brushless joint motors price similarly — it is the gearboxes and the hours: cycloidal gearboxes must be printed, assembled and run in, and there are more motors. What the money buys is a structure you control, not more capability; on performance the two machines are the same tier.
Printing and machining: Many parts, mostly load-bearing (gearbox housings, links), which makes this project more sensitive to orientation and material than typical printed robots: the eccentric shafts and bearing bores of a cycloidal gearbox set the backlash directly, and PLA creeps under sustained load — PETG or better for structural parts. Print time is counted in weeks; plan printer capacity accordingly.
The hard step: Assembling and running in the cycloidal gearboxes. Print tolerance stacked on eccentric assembly means the first gearbox set almost never runs smoothly — that is the price of making a humanoid 'affordable', and it is exactly the work you skip when buying finished joint motors. Second hardest: control-stack deployment — documented, but the environment combination is yours to break in.
What we checked: We verified: the project's positioning and cost figure (paper and release pages); the power architecture (printed cycloidal gearboxes + brushless motors); and the editability claims for the engineering files. We did not replicate it — measured backlash figures and whether the first gearbox set goes together come from community discussion, not our bench. The grade stays accordingly.

This site's call

For two kinds of builder: those whose goal is building the humanoid itself (the engineering content is a tier above LeRobot Humanoid), and those who want to modify the structure for research (editable sources). If you want the fastest route to training policies, buy the LeRobot Humanoid; if you want to take a humanoid apart mentally as well as physically, this is the one.

Two humanoids, two routes

	LeRobot Humanoid	Berkeley Humanoid Lite
Parts cost	About USD 2,500	About USD 5,000
Joints	Finished integrated joint motors (CAN FD)	Printed cycloidal gearboxes + brushless motors
Structure files	STL (no editable sources)	Full engineering files
Where your hours go	Assembly and bring-up	Printing, gearbox assembly and run-in
For	Getting to policy training fast	Modifying structure, learning engineering

The real difference between the routes

Not the USD 2,500 gap — your relationship to the machine. One is a platform you received, where all your hours go into what runs on it; the other is a machine you made, where half the hours go into the machine itself. Both roads reach a humanoid; the scenery does not transfer.

Sources

Berkeley Humanoid Lite paper and project page (cost, power architecture)
Open repository (engineering file scope and licence)

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Last checked 2026-09-28