Im sorry I missed this questions and didnt reply sooner. The software I wrote for the AR2 is currently setup for stepper motors, the reason is cost. The entire goal of the AR2 is to make a 6 axis robot affordable and I have not yet found affordable servo options that also support the needed gearboxes. I will continue to work on updates for the AR2, I am looking at options to add encoders to the AR2 stepper motors to make the robot closed loop but my goal is to keep cost to a bare minimum and make sure everything is backward compatible as that is very important to the project.