title: Documentation of Open Hardware
description: In this lesson, we want to get you familiarized with good open hardware documentation. This includes considerations about what to put in the documentation, different types of documentation, formats, as well as tools, and platforms to publish documentation. We will cover basic and introductory aspects of documentation and more advanced considerations, practices, and setups.
authors: Jerry de Vos, Jose Urra
# Documentation of Open Hardware
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**Date of release:** 15-08-2022
In this lesson, we want to get you familiarized with good open hardware documentation. This includes considerations about what to put in the documentation, different types of documentation, formats, as well as tools, and platforms to publish documentation. We will cover basic and introductory aspects of documentation and more advanced considerations, practices, and setups.
**By the end of this lesson you will**
- Learn key principles for good documentation
- Get started with documenting your project
- With this understanding we hope you feel more prepared when working on an open hardware project
**Considerations and prerequisites**
- This lesson is for absolute starters with no previous experience with hardware documentation
- It also contains more advanced contents for those learners that already have experience with hardware documentation
- Identify what makes your hardware project documentation complete
- Match your level of development with the documentation tools you need
### :rocket: Before you start with the lesson
For the sake of simplicity, we will touch upon the fundamentals of documentation that can help you get started right away. For advanced learners looking into more detailed knowledge and tools, we have created a set of Appendixes touching upon advanced documentation, standards, more complex documentation examples, platforms, and some tools to generate hardware documentation.
In a nutshell "**Open source hardware** is hardware whose design is made publicly available so that anyone can study, modify, distribute, make, and sell the design or hardware based on that design." [Read more on OSHWA declaration of principles as well as definitions](https://www.oshwa.org/definition/#:~:text=Open%20source%20hardware%20is%20hardware,for%20making%20modifications%20to%20it).
Before we start providing tips, recommendations and considerations for good documentation we want to go through some concepts to break down the subject a bit.
## Ideal documentation model
**How can we facilitate the implementation of the rights with good documentation?**
The following model(topology) proposed by Jérémy Bonvoisin and Robert Mies published in ["Measuring Openness in Open Source Hardware with the Open-o-Meter"](https://www.sciencedirect.com/science/article/pii/S2212827118312095) is a great documentation model to formalize how principles and guidelines in openhardware map to the actual documentation.
:warning: We would like to add that the process of achieving this can be progressive and iterative and may include best practices, selection of tools and software, engineering craft, and daily documentation.
Normally the design and prototyping phases are messy and experimental and during these phases you don't need to have perfect documentation all the time. **Nevertheless when releasing and sharing with others this mindmap can serve as a checklist to spot things you might be missing for your next release.**
## Different kinds of documentation
In general, we can say there are two main groups of documentation:
1. There is **documentation about the hardware design to be released**, including how to replicate it, get started with it, and so on.
2. And then there is **project documentation**, which includes what the current status of development is, what issues are being addressed in development, how to contribute, submit an improvement, mailing lists, and bug trackers among other examples.
If you are looking for advanced documentation concepts and practices we recommend you to go to the [appendix on advanced documentation](#Appendix-1-Advanced-documentation).
### Minimum hardware design documentation:
* Bill Of Material
* Written build instructions
* Images of build instructions
* Instructions to verify correct functionality
* Example uses of the product
* Optional: Video of build instructions.
### Project documentation
* Current state of the project
* Future plan of the project
* How to contribute
* Where to find what or ask for help
## Getting started
**The first best practice is to ask yourself:**
* What do I want to document about this project that is relevant given the current status of development?
* Who am I documenting for?
* Do the documents, files, resources, and images I provide fulfill my goals and audience considerations?
* What are things that I can forget that are worth writing about to save me time in the future?
:warning: **Only after thinking through these questions do we encourage you to look at examples and best practices.**
Don't simply apply or copy styles of documentation, as you might end up overdoing documentation. Be pragmatic and always question how much is good enough to keep progressing to the next stage in your project.
## Basic example
Let's say you want to make a whistle and you want to make it into an open source project because the world cannot have enough whistles! **Let's look at different types of documents that can go along with different hardware design activities**.
| Hardware Design activities | Type of Documents | Whistle example |
| Starting and scoping your project | Readme with motivation and status | **Goal**: Easy 3D printable whistle |
| Research about other designs | Simple overview of models in a hackmd to get feedback | Research different whistle models online |
| Prototyping and experimenting | Share this process with dates on a hackmd where people can follow up and give feedback | Sharing progress of designs and models |
| Releasing and distributing the design | Upload, and presentation on the printables platform. | Uploaded documentation and source files |
[Check the 3D printable whistle project example](https://www.printables.com/model/65397-kazoo)
:warning: This is a quite simple and straightforward project to illustrate the principles of open source documentation, and thus the documentation is easily quite complete.
But you can imagine that if the project itself gets more complicated, also the documentation gets more complicated. And you often see people making a product and putting the source files online, without any explaination.
**For more complex projects we encourage you to go through the references and appendixes.**
## Hardware project structure and documentation
If you are just getting started with documentation, this section recommends a simple approach to keep things moving forward. This setup will allow you later to add more levels of complexity.
Overall keep your project organized and portable. A folder for small and medium sized projects with a set of subfolders and files can be effective, and eventually zipped ;)
**A folder containing:**
- A readme with instructions (The readme can be formatted in markdown already)
- Source files (CAD, Technical drawings, schematics)
- A folder with source code if applicable to your project
- A sheet with the bill of materials and
- the tools needed to build the project
**A basic project folder could look like this:**
- project folder
| | |_CAD
| | |_CAM
| | |_schematics
| |_ |_...# Same as above
| |_ |_src # You can have a dedicated structure for code with conventions
| |_ Getting_started.md
| |_ Tutorial.md
| |_... # other complementary documents
|_Contribution_guidelines.md # When releasing
|_Metadata_file.yaml # if applicable
::: spoiler **Why we recommend Markdown**
**What can you do with markdown**
If you write your documentation in markdown you can easily publish it on many platforms, you can generate documentation websites and even pdfs out of them. [pandoc.org](https://pandoc.org/) for example has a cli that allows you to generate presentations and pdfs from markdown source files.
**What is Markdown**
Markdown is a style and format for writing not connected to a certain program. This page is written in markdown, github/gitlab documents are written in markdown, as well as many open source documentation websites.
## Good vs not so good documentation
| example of good documentation | example of not so well documented hardware |
| -------- | -------- |
|https://github.com/pikvm/pikvm | https://github.com/j-ferretti/open-aed-hardware |
|!(https://i.imgur.com/7TNDZpc.png) | !(https://i.imgur.com/GJcn4JW.png)
| this documentation is good because there are docs, instructions, frequent updates, and a community|this documentation is not so good because it only has hardware files and no explanation.
## Excercise 1: Start sharing your documentation
- Write a simple introduction to your project assuming that the audience is new to the topic and not familiarized with it.
- Make it in a format that can be easily edited, presented, and shared online.
- If you are just getting started, we recommend starting with Markdown and hackmd as a platform to present, share and get feedback.
- This will make it easy for the mentors to comment and help you out)
- Alternatively, if you have already a git repository or documentation published in a platform of your preference feel free to reuse that and avoid repeating yourself.
:::spoiler **Answer from last year**
## Excercise 2: See how others do it
- Find an open source project, this can be one that you found last week, and see how they did their documentation, it can be handy to make an overview or to write down what you liked and what you did not like.
- You can do the following:
- Reflect on how open it is and how easy it is to get started with it.
- Reflect back on your documentation to see if you can improve it based on looking at other projects.
:::spoiler **Answer from last year**
**Nanami:** Elektronika-1 A replacement module for a USSR made vintage LED watch
I decided to pick the [ELEKTRONIKA-1 - A replacement module for a USSR made vintage LED watch anno 1978](https://github.com/BenjaminSoelberg/elektronika-1) project by Benjamin Soelberg.
>Why? It seems to have some decent documentation, and it revitalises old hardware, which is a good challenge.
* Pictures of the actual device
* Some background about the original hardware
* Good high level overview
* Lists practical performance and limitations
* Hardware motivation
👎 Could be improved:
* Repository images could be in a subdirectory (it's messy now)
* Software setup / microcontroller programming could be explained
* `docs` directory seems to contain mostly background research material, should perhaps be somewhere else
* Add a little video in action
* In general not set up fully for reproduction (but given the niche nature of the project, that's understandable)
But all in all, the project is all available if you are willing to take the time to sort through the files. Given how niche it is, it is a commendable effort. I have seen much much worse.
## Excercise 3: Make a plan for the future
- Make a checklist of what your documentation should look like by the end of the program.
- Assess if it is too much for your current status or is a good match.
:::spoiler **Answer from last year**
**Nemo:** LED driver board documentation targets
*This pertains to my LED driver PCB sculpture project. When the hardware is tested and finalised the documentation should contain*
* landing page, little demo webp video preview, project at a glance
* Component lists, and where to source them
* Assembly instructions
* Instructions on setting up the ESP-32
* Instructions on running a hardware check + the code to run that check
* Warnings on power supply choices and usage
* Explaination on the artwork/biology behind the item
* Comments on hardware choices (why this component, not another)
* PCB walkthrough
* Extendability guide (Rust code - e.g. flash lights upon email)
 The Art of Documentation for Open Source Projects - Ben Hall, Katacoda, (Dec. 16, 2018). Accessed: Aug. 10, 2022. [Online Video]. Available: https://www.youtube.com/watch?v=Yjxupg-NKnA
 J. Bonvoisin, J. Molloy, M. Häuer, and T. Wenzel, “Standardisation of Practices in Open Source Hardware,” Journal of Open Hardware, vol. 4, no. 1, Art. no. 1, Aug. 2020, doi: 10.5334/joh.22.
 “The How and Why of Organizing Your Hardware Design Project’s Digital Files,” Awkward Engineer. https://www.awkwardengineer.com/blogs/awkward-engineer-blog/the-how-and-why-of-organizing-your-hardware-design-project (accessed Aug. 10, 2022).
 “Your future self will thank you: Building your personal documentation,” GitHub. https://github.com/readme/guides/private-documentation (accessed Aug. 09, 2022).
 “DIN SPEC 3105 - Open Source Ecology.” https://wiki.opensourceecology.org/wiki/DIN_SPEC_3105 (accessed Aug. 03, 2022).
## Appendix 1: Advanced documentation
The [divio documentation system](https://documentation.divio.com/introduction/#making-documentation-work) for software has some nice insights on software documentation which we think can be applied also to hardware design documentation.
:+1: Divio documentation is used by [Django](https://www.djangoproject.com/)
[Divio documentation system](https://documentation.divio.com/introduction/#making-documentation-work)
> There is a secret that needs to be understood in order to write good software documentation: there isn’t one thing called documentation, there are four.
> They are tutorials, how-to guides, technical references, and explanations. They represent four different purposes or functions and require four different approaches to their creation. Understanding the implications of this will help improve most documentation - often immensely.
In the context of open hardware [precious plastics](https://preciousplastic.com/solutions/machines/overview.html) is a good example of rich documentation that includes tutorials, explanations, videos, and a variety of rich materials that makes its documentation and project rich, participative. You can think of this as an ecosystem of interactive documentation and content.
## Appendix 2: Open Hardware documentation standards
The standardization of open hardware documentation is still at its very beginning, due to the complex nature of hardware projects compared to software. Hardware projects use different types of technologies, tooling, and file formats. Different types of components use different files for example and open source tools for CAD design are not as competitive as open source tools in the software domain.
Nevertheless, there are very interesting developments that we will list here for you to review and consider, especially when your project reaches more mature stages of development and toward more ambitious releases.
[Open Hardware Observatory](https://en.oho.wiki/wiki/Home)
[DIN Spec 3105](https://en.oho.wiki/wiki/DIN_Spec_3105)
[DIN SPEC 3105-1](https://www.researchgate.net/publication/342564027_DIN_SPEC_3105-1_Open_Source_Hardware)
[Open Hardware Observatory standards for technical documentation](https://en.oho.wiki/wiki/Technical_documentation)
[Open know how specification](https://standards.internetofproduction.org/pub/okh/release/1)
# Appendix 3: Platforms for publishing
We often get the question of what the best place is to host open hardware projects, and we don't have an exact answer. This depends heavily on what technologies are being adopted, and which platforms your target audience normally visits, among many others. **This is why we highly recommend documenting projects as platform agnostic as possible.**
We provide a list of services that we find are regularly being used when publishing open hardware.
### Platforms dedicated hardware and open hardware
- [Open Hardware repository](https://ohwr.org/explore/projects/starred)
- [Open Hardware Observatory Search Engine](https://en.oho.wiki/wiki/Special:RunQuery/projectSearch)
### Widely used platforms
Find the platform that works the best for you!
By now there are quite a lot of different options, for example:
- [Google drive](https://www.google.com/drive/)
The open hardware repository is an instance or clone of gitlab solely dedicated to open hardware.
## Appendix 4: Documentation generation tools
:construction: This topic is so rich and broad that we are keeping it really simple for now. A better version of this lesson should explain what is interesting about this particular list.
### Specific to open hardware and open source
### Generic and open source
[Hackmd powered by CodiMd](https://github.com/hackmdio/codimd)
Wikis have been widely popular in the context of open hardware, the reprap project, open source ecology, or appropedia are all using wikis
Static website generators are used in general, there are so many wonderful static website generators and many of them are open source. We recommend you to simply surf the web and find out about them. For the sake of simplicity, we only added JupyterBook
## Appendix 5: Example of complex projects
[Opulo Pick And Place](https://docs.opulo.io/)
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