3D printer as base
Upgrade some parts to make our own setup: https://www.prusa3d.com/prusa-i3-printable-parts/
(Original Prusa i3 MK2S MK3S upgrade)
Or mod thingiverse file to support a gripper: https://www.thingiverse.com/thing:1883830
Octoprint
Rotating option to 3D printer: https://www.thingiverse.com/thing:1688026
Tool changer
Facebook group: Tool Changing 3D-Printers
Open source (jubilee): https://www.thingiverse.com/thing:3843001?fbclid=IwAR0-JL8VGYmNDqQPIiLWJnF6HYCU7tCSKUiu0L8ehfQqxnkZIT-Sy6MPVA0
Twitter: https://twitter.com/Poofjunior
Note about the firmware for toolchanges:
As for firmware, luckily, there are no firmware changes. Since the Duet controller lets you write Gcode scripts, you need only add these config files to your board's SD card, and then tool changes will work with "T0" "T1" commands.
https://github.com/Poofjunior/jubilee_configs
Note: these config files are somewhat behind my current machine, but they are functional. I will also update them shortly.
E3D open sourced the toolchanger!:
https://github.com/e3donline/ToolChanger?fbclid=IwAR3AfcNA40bzo25NnZedp5hemFyghGXdyUafsoJdctVVCyIsvcSYl17yStg
E3D also sells a version.
Grippers:
Pump driven with stepper: https://www.thingiverse.com/thing:398024
Redesign of 3D printer. What should move on the printer? Bed stationary or tool stationary?