Elegoo Centauri CANVAS Filament Hub & Sensor Relocation

This is a work-in-progress prototype, print and use at your own risk.

So the Elegoo Centauri Carbon is a decent printer, but when combined with the CANVAS unit it has some trouble with abrasive filaments. The CANVAS unit itself isn't abrasive-proof, and neither is the toolhead filament detector. This model is part of a larger project aimed at fixing that. 

This model allows you to relocate the 4-to-1 filament matrix and the PCB from the CANVAS extruder while (hopefully, I haven't worked out the software yet) retaining the functionality of both the tangle detector and the filament detector. This mod is meant to be paired with a microswitch sensor at the toolhead. 

At the time of writing, the plan is to wire the filament detector to the unused runout sensor port on the mainboard, while the tangle detector will get wired to the unused fan tachometer pin. I'm not sure what things look like for the Centauri 2, but I hear they aren't as I/O constrained. Naturally you'll need to be running OpenCentauri Cosmos to have software support for this. I haven't really figured out what needs to be changed in the software yet though. 

I'm reusing the following non-printed hardware scavenged from the Centauri's runout sensor for this:

• 1x 603zz bearing

• 1x 624zz bearing (modified with a v-groove)

• 1x 3mm OD dowel pin

• 1x spring with 6-7ish mm OD

The pivot arm mechanism concept is entirely stolen from the original runout sensor.

In case it wasn't clear, this model is a prototype. I'm mostly posting it at this time so people smarter than me (or at least people who have more time to tinker with their printers) can give feedback.