pyGCodeDecode

What is this repository for?

For the analysis of GCode, slicers or dedicated analyzer tools, such as [Prusa Slicer][prusa_slicer] or [gCodeViewer][gcodeviewer], merely display target process parameters. The actual process velocity however is determined by the firmware of the printer. Velocities are expected to deviate significantly from the target velocity at times of acceleration and deceleration. pyGCodeDecode aims to model the machine's actual behavior and visualize its influence. A visual comparison between the simulated acceleration approach and the raw GCode target velocity is shown below.

This package reads the target trajectory firmware settings changes from a GCode file. Subsequently, it simulates a motion planner with acceleration and jerk or junction control respectively. The more accurate modeling is achieved by replicating [grbl][grbl]'s and its derivatives' firmware-specific movement planner solutions, such as "Classic Jerk" and "Junction Deviation", as an interpretation for Jerk. The simulation result is a description of the nozzle and extrusion axis position and velocity over time and is easily accessible for further analysis. For example it can be used to generate time dependent boundary conditions, needed in additive manufacturing simulations for the Fused Filament Fabrication (FFF) process. The package includes 3D plotting functions, so it can be used to visualize local velocities before printing to improve your process understanding.

Install pyGCodeDecode

It is recommended that you first create a virtual Python-environment, e.g. using the venv-module built into Python. You can clone the repository and run

pip install .

from inside the root directory. Alternatively you can simply install from PyPI:

pip install pyGCodeDecode

If you plan to contribute to the development, install in development mode and with the additional dependencies:

pip install -e .[DEVELOPER]

You may want to verify the installation and version. Inside your environment, just run:

python -c "import pyGCodeDecode
print(pyGCodeDecode.__version__)"

This should return the correct version.

Running the CLI

pyGCD comes with a simplistic CLI to quickly run the provided examples or plot some G-Code without writing a script first. If you want to see something quickly, activate the venv where pyGCD is installed and run:

pygcd run_example brace

You can also run and plot your own G-Code with:

pygcd plot --gcode