I think it would be cool to build a robot that can input a digital image and output a finished watercolor painting. The Liquid Lite Brite is my first step towards actualizing that idea. The robot mixes CMYK dyes in microplate wells to produce the proper color, and it will eventually be modified to produce watercolor paint trays.
I'm fortunate to have access to a number of different tools, and this machine was built using a combination of SLA, SLS, and FDM 3D printing, Waterjet Cutting, Laser Cutting, Manual Machining and CNC milling.
The robot is driven by three stepper motors for positioning and one stepper motor for running the peristaltic pump. It uses five servos to control valves that allow the machine to autonomously swap between different colors. I added a PCA9685 i2c servo expander to the Arduino Mega 2560 + Ramps 1.4 setup to add more servo pins.
The script is written in Python, and it starts by iterating through all of the pixels in the input image and assigning them an RGB value. The RGB value is then converted to CMYK and translated to the number of extruded steps needed to dispense the correct amount of dyed liquid.
There were a lot of small details to sort out for this project that I went into greater depth on in my portfolio. Thanks for checking my project out if you've gotten this far! I'd love to hear any suggestions for improvements or concepts that this could be used for.