PSim

This repository holds all GNC code for the PAN mission. It will be comprised of two main modules:

1. GNC algorithms and utility functions implemented in C++ that will be used by flight software and our internal simulation - PSim.
2. PSim models and simulation implementations.

MATLAB code listed in MATLAB/** is deprecated and will be phased out by the new C++ implementation of PSim.

See the full set of documentation here including installation instructions.

Getting Started

GNC Development

Setting up the PlatformIO build system for GNC development can be done with the following:

python3 -m venv venv
. venv/bin/activate
pip install --upgrade pip
pip install -r requirements.txt

You can ensure PlatformIO is behaving properly by running:

. venv/bin/activate
pio test -e native

Note: Using you're system's default Python 3 is recommended if you will also be developing/working with PSim. PSim will build Python extensions using the development headers associated with your system's default version of Python 3.

PSim development

For PSim development, there are the following additional requirements:

• The Bazel build system.
• Python 3 development headers installed on your system.
• Python 3 distutils package installed on your system.

All three of these should be available via your systems package manager. The last build dependency (Python's distutls) is most likely installed on your system already so it may be worth giving building a go and see if Bazel/Python complain.

On a Debian based system, the Python development headers can be installed with:

sudo apt-get install python3-dev

and Bazel install instructions (for other platforms too) can be found here.

To ensure everything is working as expected, you should be able to build and run the C++ unit tests for PSim with:

bazel test //test/psim:all

The PSim Python module can be compiled, installed, and run with:

python3 -m venv venv
. venv/bin/activate
pip install --upgrade pip
pip install -r requirements.txt
pip install -e .
python -m psim --help

Note the you can add the -vvv flags to the pip command to see compilation errors if the install fails. It's also recommended to use the -e flag to build PSim in place which avoids making Bazel track a new repository that pip would essentially create otherwise.

When making changes to PSim, simply run pip install -e . again to have Bazel recompile the needed C++ files and pip update the Python source files.

Bazel VSCode Extension and C/C++ Intellisense

It's also recommended to install the Bazel build tools along with the VSCode extensions 'Bazel' by the 'Bazel Build Team'. With this extension plus configuring C/C++ intellisense according to tools/bazel-compilation-database.sh the Bazel build system should integrate fairly well with VSCode.

To ensure everything is working as expected, you should be able to run the following successfully (make sure you're in your virtual environment when working with Bazel as well):

bazel test //test/psim:all

GNC

The GNC library is a set of flight software algorithms (mainly controllers and estimators) along with a myriad of utility functions.

The source code for the GNC library lives in include/gnc/** and src/gnc/**. The associated unit tests are located in test/gnc/** and can be built with PlatformIO using the following command:

source venv/bin/activate
pio test -e native

PSim

The actual infrastructure for PSim is slightly fluid at the moment; however, this PR have a good overview of the architecture: #231.

The code lives under include/psim/** and src/psim/** and leverages the GNC modules as a dependency. Unit test are implemented under test/psim/** and can be run with the following command:

bazel test //test/psim:all --test_output=all

If you're interested in running the standalone version of PSim, you should install a development version of the PSim module locally in you're virtual environment:

source venv/bin/activate
pip install -e .
python -m psim --help

From there, you should be able to run PSim standalone cases, start simulation off with difference configurations, and plot state fields over the course of the simulation. Note, that pip install -e . calls the setup.py file which calls Bazel. Therefore, if any C++ changes are made you must reinstall the PSim module with pip to update the PSim binaries. Note the -e flag ensures pip doesn't copy the entire respository and rebuild for each install.