Taproot

A friendly control library and framework for RoboMaster robots.

Taproot provides a comprehensive, convenient and well-tested set of APIs designed specifically for the RoboMaster robotics competition. Key functionality and features include:

• Drivers for common RoboMaster/DJI hardware:
  • RoboMaster motors connected via CAN: C620, GM3508, GM3510 and others
  • DR16 Receiver
  • RoboMaster referee system via UART
• An organizational framework and round-robin scheduler taking inspiration from FIRST's wpilib
• Common building blocks such as:
  • Setpoint-based subsystems with jam detection logic and calibration
  • Closed-loop power limiting
  • Filtering, smoothing and ramping primitives
  • Computational helpers for wrapping measurements such as angles
• Built-in error aggregation and reporting via optional UART terminal or OLED display
• Monitoring of key subsystems and status information via optional UART terminal or OLED display
• First-class support for unit and integration testing (no hardware required)

Taproot is a C++ library targeting modern C++ (C++20).

We use:

• modm, a C++-native HAL
• the gcc compiler
• openocd to deploy and debug
• VSCode, an editor

This library was originally designed for use in Advanced Robotics at the University of Washington ("ARUW")'s robot controls code, which remains the largest consumer. You can find the project here.

In addition to this readme, check out our GitLab wiki, generated documentation and the other resources linked below!

Getting started

Check out the template project to help you set up a new project. Refer to the resources below for other project information.

See "Development guide" below for information on contributing to this project.

Resources

• The generated API documentation for Taproot
• aruw-mcb, ARUW's full robot code project
• aruw-edu, a hands-on tutorial for building robot code with Taproot
• taproot-examples, small self-contained code examples
• The template project to kick-start your own development
• The Taproot wiki
• The modm website and associated documentation

Requirements for use

• A robot operated by a RoboMaster Development Board Type A or Type C.
• A Linux, macOS or Windows computer
• An ST-Link- or J-Link-compatible probe for flashing and debugging

Contacting

If you have any questions please file an Issue on GitLab or join our Discord server (linked above). We can also be reached privately at [email protected].

Licensing

Taproot is covered under the GPL-3.0-or-later with the following exceptions:

• The /modm submodule is licensed under MPL 2.0 by the modm project. We are not the license holder for these files. See /modm/LICENSE for license information.
• src/taproot/algorithms/MahonyAHRS.h and src/taproot/algorithms/MahonyAHRS.cpp are licensed under the GPL by SOH Madgwick. The repo containing this code can be found here.

Other RoboMaster teams are invited, and encouraged, to utilize this library. We have licensed Taproot and the template project under the GPL to encourage collaboration and open publishing of RoboMaster controls codebases. We politely request that other teams choosing to utilize this library, or parts of it (including its design), open-source their own code in turn.

Contributing

We welcome Merge Requests and Issues! Feel free to take on an open Issue if you see one valuable to you. We recommend posting to let us know what you're working on so we don't duplicate effort.

All development happens on GitLab (not GitHub).

Issues and our Discord server are both great ways to get in touch.

When you create a new branch, always branch off of develop.

To learn about contributing to upstream repositories via forks, see here: https://docs.gitlab.com/ee/user/project/repository/forking_workflow.html.

Development guide

If you are looking to develop your own Taproot-based project, refer to the README there for setup instructions. The below is for developing Taproot itself. The instructions are very similar but may be customized per project.

System setup

Follow the guide appropriate for your operating system.

• Linux
  • Debian: https://gitlab.com/aruw/controls/taproot/-/wikis/Debian-Linux-Setup
  • Fedora: https://gitlab.com/aruw/controls/taproot/-/wikis/Fedora-Linux-Setup
  • Other: follow one of the above guides, substituting your distribution's package names in place of Debian or Fedora packages.
• macOS: https://gitlab.com/aruw/controls/taproot/-/wikis/macOS-Setup
• Windows: https://gitlab.com/aruw/controls/taproot/-/wikis/Windows-Setup

Then install pipenv and set up the build tools:

pip3 install pipenv
cd test-project/
pipenv install

Alternately, you want the easiest setup experience and do not require deploying code to hardware, consider developing within the provided Docker container. If you have Docker and vscode installed, you can access this environment in one click using the badge at the top of this repo. We do not recommend this approach for robot development.

Sometimes setting up your machine can be tricky. If you are having trouble setting up your environment, feel free to ask for help on our Discord server.

Working on Taproot

Most of the time, you want to interact with Taproot from within a project that uses it. Taproot itself is just a library of code templates; it becomes a fully-fledged buildable entity only when you configure it and generate an instance of it for your usage.

See here for more details on this flow.

For these reasons, the typical way to work with Taproot is from within the project you use it in. You can edit the top-level taproot submodule and re-run lbuild build to update your in-project copy of Taproot according to the modifications you made to the templates.

If you make changes to your taproot submodule and want to keep them, you'll need to commit it to a branch. Unless you have "push" access to the main Taproot repo, you'll need to:

• Fork Taproot under your own name on GitLab
• Push your changes to that fork
• Either open an MR for those changes against our repo, or change your own project to use your fork's version

This is not a trivial process, but please do let us know on Discord if you'd like some help!

If you aren't using Taproot within your own project, or would like to avoid the workflow above, this repo includes a dummy project in the test-project folder. You can run lbuild build within that directory to get a copy of Taproot generated locally. This copy supports building and running tests like any other.

Branch naming conventions in the Taproot repository

Names should follow the format FirstL/#{Issue Number}/short-description. For example: RyanT/#0/linter-integration.

Building and testing via the terminal

This library is configurable via lbuild parameters, and consumers use this tool to generate a full copy of the files in Taproot in their own projects. As such, there is no "one true configuration" for consumers using Taproot. See here for more details on this flow.

To facilitate testing, this repo has a project defined in test-project/ which consumes Taproot. It can be used for basic testing and as a generation/build smoke-test. Note that changes made by ARUW members should typically be tested in the context of aruw-mcb before being merged here.

To use the test project, cd into taproot/test-project (where the project.xml file is). Run pipenv shell to enter the environment with appropriate Python build tools. Then, run lbuild build as described below to generate an Taproot distribution. Then use scons to perform the desired builds.

The test-project is a normal Taproot user project, except it configures Taproot to generate its own unit tests into the project. This means that running test-project's tests runs the tests for Taproot itself against the version of Taproot generated for the test-project.

Likely commands are as follows (all from within a pipenv shell or prefixed with pipenv run <command>):

• lbuild build: Re-generates our copy of modm according to the modules specified in project.xml.
• scons build: Builds the firmware image for the hardware target. Creates a "release" folder located in build/hardware/ which contains the final .elf file as well as the intermediate object files (.o).
• scons build-tests: Builds a program which hosts our unit tests. This executable can be run on your host computer and prints results for each unit test run.
• scons run: Builds as with scons build and then programs the board.
• scons run-tests: Builds and runs the unit test program. In test-project, this includes all of the unit tests for Taproot itself. Same as build-tests but also runs the built file.
• scons size: Prints statistics on program size and (statically-)allocated memory. Note that the reported available heap space is an upper bound, and this tool has no way of knowing about the real size of dynamic allocations.

Working with modm

What is modm?

We use an embedded library generator called modm in our codebase. It will eventually be important that you understand what how modm works. For now you can just think about it as handling lower level IO on our MCB. You should read modm's homepage so you have a general idea of what it does.

Modm examples

The modm website provides a great number of examples that can be very useful when interacting with modm's hardware architecture layer for the first time. The examples are located on modm's website here.

Adding new dependencies on modm modules (advanced)

Look up the fully-qualified name of the module from the modm website or select one from the output of lbuild discover. The name will look like :platform:gpio. Open taproot/build_tools/project.xml.in and add an entry to the dependencies section like the following:

<module>modm:platform:gpio</module>

Now open the terminal, cd into test-project, and run lbuild build.