I am working on my own version of the very popular "cat feeder" project. Except my device will feed my 60lb labrador. That being said, I will use your usual cereal dispenser but will modify it to hold a lot more food than just a small plastic cilinder. I have come to ask for help with my hardware selection.
I will use my photon to control a stepper to turn the dispenser knob. For the driver I looked into the Big Easy Driver by Sparkfun but I read that while operating at 2A you need to add a heatsink and I don't want to keep complicating this project so no decision so far.
For the motor I am looking into a NEMA 17 of at least 80+ oz.in like this one:
here the specs:
The reason for the torque requirements is because I read an "Arduino cat feeder" tutorial where the author stated his 70+in.oz sometimes didn't have enough torque to turn the knob of a medium-size cat food container. so maybe 80+oz.in will be enough for me, maybe not I don't know.
Bottom line is I still don't have a driver, would anyone recommend a driver that would work with my photon and this stepper motor? or another stepper motor of around 80 oz.in or more and a driver for it?. It's my first project so feel free to critique and or advise, anything helps.