I know that the PID feedback controller has been done via arduino. I'm not that well knowledgeable in controls and I am wondering if there are other good alternatives to the PID controller. I want to see if I can program those too.
under Miscellaneous you see the following which may be helpful.
Controller Upgrade Options
Various upgrades are presented including absolute and SSI encoder interfaces, backlash and leadscrew compensation, antifriction bias, two sets of PID and more.