本仓库采用双许可证 / This repository is dual-licensed
=====================================================

1. Apache License 2.0 —— 本项目原创的代码与工具
   Apache License 2.0 — original code and tooling by this project

     scripts/              渲染、导出、孔位分析脚本 / rendering, export, hole-analysis scripts
     tools/                零依赖 STL 查看器 / zero-dependency STL viewer

   Apache-2.0 全文 / full text: https://www.apache.org/licenses/LICENSE-2.0


2. CC BY-NC-SA 4.0 —— 上游 3D 模型的衍生作品，以及本项目的文档
   CC BY-NC-SA 4.0 — derivative works of the upstream 3D models, and this
   project's documentation

     assembly-drawings/    渲染图与爆炸图（由上游 MJCF + STL 生成）
                           renders and exploded views, generated from upstream MJCF + STL
     cad/                  已应用世界变换的装配体 STL（由上游 STL 合并）
                           "assembled" STLs with world transforms applied
     print/                46 个单件 STL —— 上游 STL 的再分发（重命名与分类）
                           46 individual STLs — redistribution of upstream STLs
                           (renamed and sorted)
     docs/hole_analysis.json
                           由上游 STL 计算得出的孔位数据
                           hole geometry computed from upstream STLs
     *.md, docs/*.md       全部文档与逆向分析文本
                           all documentation and reverse-engineering text
     build-log/, assets/   实物照片与图片素材，由本项目参与者拍摄并授权
                           build photos and image assets, shot by and licensed
                           from project participants

   这些内容中，几何部分是 Pollen Robotics 的 Microduck 3D 模型（CC BY-NC-SA）
   的衍生作品，依据 ShareAlike 条款必须沿用相同许可证；文档部分由本项目主动
   采用同一许可证，以保持整体一致。

   The geometry here is derivative of Pollen Robotics' Microduck 3D models
   (CC BY-NC-SA) and must carry the same licence under ShareAlike. The
   documentation adopts the same licence by choice, for consistency.

   CC BY-NC-SA 4.0 全文 / full text:
   https://creativecommons.org/licenses/by-nc-sa/4.0/


说明 / Notes
------------

- software/training/ 保留训练工程自己的许可证边界：代码、配置、参数、上游文档与
  本目录新增文档采用 Apache-2.0（全文见 software/training/LICENSE），3D 模型和
  网格保留上游 CC BY-NC-SA 声明。上面的文档 CC 许可不覆盖此目录的 Apache 文档。
  software/training/ retains its own licensing: code, configuration, parameters,
  upstream documentation and new documentation in that directory are Apache-2.0
  (full text in software/training/LICENSE); 3D models and meshes retain the
  upstream CC BY-NC-SA statement. The documentation licence above does not
  override Apache-licensed documentation in that directory.
  Fixed sources and attribution: software/training/UPSTREAM.md.

- 规范名称是 CC BY-NC-SA 4.0。上游 README 写作「BY-SA-NC」，指的是同一个许可证。
  The canonical name is CC BY-NC-SA 4.0; upstream writes it "BY-SA-NC" — same licence.

- 文档中引用的上游源码片段（注释、常量、寄存器定义）来自
  pollen-robotics/microduck，遵循其 Apache-2.0 许可证，引用处均标注了文件路径。
  Source excerpts quoted in the documentation come from pollen-robotics/microduck
  under Apache-2.0, with file paths cited at each quotation.

- 非商业性使用：CC BY-NC-SA 禁止商业用途。本仓库仅供学习、研究与个人复刻。
  Non-commercial: CC BY-NC-SA forbids commercial use. This repository is for
  study, research and personal replication only.

完整署名与合规声明详见 NOTICE.md
Full attribution and compliance statement: see NOTICE.md
