Licensing
Snapshot of this document in the GEMs repository. The repository itself is the current version. Bản chụp tài liệu này trong repo GEMs. Bản đang chạy nằm ở chính repo.
Copyright © 2026 Plone Mraz.
This repository holds three different kinds of work, and each is licensed under the instrument built for it. Pick the row that matches the file you are looking at.
| What | Where | License | SPDX |
|---|---|---|---|
| Hardware designs — mechanical and electrical CAD, schematics, PCB layouts, bills of materials, fabrication files | mechanical/, electrical/, sim-model/ |
CERN Open Hardware Licence v2 — Strongly Reciprocal | CERN-OHL-S-2.0 |
| Software — firmware and software source, build scripts, tooling | firmware/, software/, scripts/ |
Apache License 2.0 | Apache-2.0 |
| Documents — specifications, protocols, documentation, this README | spec/, protocol/, docs/, root-level Markdown |
Creative Commons Attribution 4.0 International | CC-BY-4.0 |
Where a file's kind is not obvious from its path, the kind decides, not the path. A schematic that happens to live next to source code is still a hardware design.
What each choice means in practice
Hardware is strongly reciprocal. If you build a product from these designs and distribute it, you must make your modified designs available under the same licence. You may sell what you build; you may not close the designs. This is the deliberate part of the choice: a body meant to be externally verifiable does not stay verifiable if its derivatives can be shut. It is also the restrictive part — an integrator who needs to keep design changes proprietary cannot use this repository's hardware.
Software is permissive. Apache-2.0 lets anyone use, modify and ship the firmware and software, including in closed products, and it carries an explicit patent grant from contributors. The reason for not matching the hardware's reciprocity here is practical: this code has to sit alongside the existing robotics ecosystem, most of which is Apache-2.0 or BSD, and a copyleft licence would cut it off from exactly the projects most likely to use it.
Documents are attribution-only. The specifications are meant to be cited, quoted and implemented freely, including by people building something that competes with this. CC-BY-4.0 asks only for credit. A conformance protocol that nobody can implement without a licence negotiation is a dead protocol.
The audit guarantee does not come from the licence. Nothing here forces an implementer to be honest, and no licence could. What a body must do to be called conforming is set by the conformance protocol, not by copyright — a body either emits the verifiable trace the protocol requires or it does not conform. Copyright keeps derivative designs open; the protocol is what makes a running body checkable.
Contributing
Contributions are accepted under the licence that already governs the file being changed — inbound matches outbound. By opening a pull request you agree your contribution is licensed that way.
Attribution
All three licences require attribution, and all three are satisfied by keeping the notices intact. Attribute as:
Huỳnh Mai Phúc (Plone Mraz) — GEMs (GYNOID ENTITY MODELS), https://github.com/PloneMraz/GEMs ORCID 0009-0009-0571-7151
Machine-readable citation metadata is in CITATION.cff; GitHub renders it as a Cite this repository button. The DOI, 10.57967/hf/11442, is the Hugging Face dataset plonemraz/GEMs.
New files should carry an SPDX header naming the author and the licence that governs them, in whatever comment syntax the file uses:
SPDX-FileCopyrightText: 2026 Plone Mraz
SPDX-License-Identifier: Apache-2.0
Notes
Directories listed above may not exist yet. The mapping is stated in advance so that the licence of a file is never in question at the moment it is added.
LICENSES/ holds the unmodified text of each licence. NOTICE carries the attribution notice Apache-2.0 asks distributors to preserve.