PiCNiC

PiCNiC is an open source program which allows you to turn your raspberry pi into a 3D CNC controller.

General information

Your raspberry pi is not able to directly drive stepper motors, it can only be used to control the motor drivers. Per default, PiCNiC is developed to drive a 3-axis CNC machine, with one motor for x and z direction each and two motors in y-direction using DRV8825 stepper motor drivers. Furthermore, a MCP23017-E/SP port expander is used (using the I2C protocol) since the raspberry pi does not provide sufficient GPIO ports for endswitches, relays, microstepping controls etc.

Features:

• control of 4 motors (two motors for y-axis)
• endswitches
• automated start/stop of millig motor
• fan control
• parsing of svg and stl files
• multiple toolpath strategies (e.g. contour, constant z, scan)
• manual controls of all axes

Requirements and dependencies

PiCNiC requires the following modules to be installed on your raspberry pi:

• pigpio
• PyQt5
• matplotlib
• scipy
• trimesh
• numpy-stl
• shapely
• pyyaml

In order to install the dependencies, you can run the setup.sh files.

PiCNiC was tested on raspberry pi 3 and 4.

Usage

First, start the pigpio daemon by executing the command

sudo pigpiod

in your console, then run the python file PiCNiC.py by executing

python3 PiCNiC.py

SVG import

PiCNiC has a built in SVG module interpreter, which allows SVG files to be parsed in two 2D strategies, namely Contour and Constant Z.

Contour

Constant Z

STL import

PiCNiC has a built in STL interpreter, which allows STL files to be parsed in both a 2D and a 3D strategy, namely Scan and Contour.

Scan

Contour

Credits

• The icons included in this repository are designed by freepik from Flaticon
• PiCNiC uses third party libraries for the communication with the MCP23017 provided by https://bitbucket.org/dewoodruff/mcp23017-python-3-library-with-interrupts/src/master/

License

MIT