OPEN-SOURCE LEG: A BIONIC LEG FOR RESEARCH LABS
A shared open platform for powered prosthetic legs — one common design plus a Python SDK, so labs stop rebuilding a bionic leg from scratch.
by Neurobionics Lab, University of Michigan
RoboticsMedical
Built withRaspberry Pi3D printing
- difficulty
- ●●●●●
- time
- a serious project
- license
- LGPL-2.1
- repo
- repo ACTIVE119 stars
●●●●● · a serious project · LGPL-2.1 · 119 stars · repo ACTIVE
WHAT YOU’LL NEED
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COMPAREE VERDICT
The Open-Source Leg is a quietly important project: instead of every lab building a powered prosthetic leg from scratch, the University of Michigan's Neurobionics group created one shared open design plus a clean Python SDK, so researchers can standardize and compare results. It's modular — knee-only, ankle-only, or full knee-ankle — and it's backed by a Nature Biomedical Engineering paper. Two things to understand: the GitHub repo you find is the control library (pip-installable), while the physical hardware (CAD, electronics) lives on opensourceleg.org and uses commercial actuators; and this is a research-grade, load-bearing wearable, not a certified medical device. For a robotics or biomechanics lab, it's an excellent standardized platform; for a hobbyist, it's more study-and-admire than weekend-build.
IN THE REPO
GOOD TO KNOW
- —The GitHub repo is a Python control library / SDK — not the hardware CAD/BOM
- —The physical knee-ankle hardware lives on opensourceleg.org (OnShape CAD, U-M electronics)
- —It targets commercial actuators (Dephy, Moteus, T-Motor) and runs on a Raspberry Pi
- —It's a research-grade load-bearing device, not a certified clinical prosthesis
Parts to buy
3 itemsFrom our check of the build. Exact quantities and part numbers are in the creator’s BOM.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Videos
Open-source bionic leg aims to rapidly advance prosthetics1:29
Michigan Engineering's overview of the platform.
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Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Read the docs (the SDK docs)
- 2.Watch the overview (what it's for)
- 3.See the hardware (CAD, electronics, community)
- 4.Install the SDK (pip install opensourceleg)
- 5.Read the paper (Nature Biomedical Engineering 2020)
Resources
Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.
KNOWN ISSUES
- The GitHub repo is the Python SDK — the hardware CAD/BOM/electronics live on opensourceleg.org, not the repo
- It relies on commercial actuators (Dephy, Moteus, T-Motor) — it isn't a from-scratch build
- It's a research-grade load-bearing device, not a certified clinical prosthesis — wearing it needs trained supervision
Is this a prosthesis I can wear?
It's a research platform, not a certified clinical device. Labs use it to study powered prosthetics; wearing it requires trained supervision and a safe rig.
What's actually open?
A shared hardware design (CAD on OnShape via opensourceleg.org) and a clean Python control SDK (pip-installable), so labs can standardize instead of rebuilding from scratch.
Do I need special motors?
Yes — it targets commercial actuators (Dephy ActPack, Moteus, T-Motor) and runs the control on a Raspberry Pi.
What does it cost?
High budget — research-grade, built around commercial actuators; the project calls the hardware relatively inexpensive, and the BOM is with the CAD on Onshape.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
The pitch is that prosthetics labs stop rebuilding bespoke legs and standardize on one shared design. Does converging on a single platform speed up research, or narrow it?
Neurobionics Lab, University of Michigan
Created a shared open-source powered prosthetic leg and a Python SDK so research labs could standardize on one platform, published in Nature Biomedical Engineering.
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CompareeTEAM2mo agoedited
Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.