Our automatic feeders are the biggest differentiator between us and other projects like ours. We laser cut the parts for our feeders locally. We have a demo video of our previous prototype of the feeders here.
Each feeder bus has a master feeder that talks back to the control computer with a USB cable. Each master feeder can be connected to multiple "daughter" feeders through a CAN (Controller Area Network) bus. The CAN bus is what is used in automobiles for reliable communication among all of the electronics in vehicles. The feeders are daisy chained together to establish communication from a feeder, to the master feeder, back to the control computer.
Various parameters stored on the feeder control the actions of the feeders, such as how many steps the stepper motor should take to advance the tape reel, how long the tape retraction motor should run, and so on.
We will release the details for all of this communication in case someone wants to use our feeders with a different machine.