Hey there, I see this was from 2014. I pulled one of these arms out of the skip and have got to work on it. Im doing a full rewire as the driver is missing and the logic circuitry outdated. Plus a few crap repairs and intermittent faults on cables. I intend to make a pcb with multiple barebone arduino unos to map the position via encoder and speed control the motion (plus end stops). I only started yesterday but im absolutely flying though it. If you would like some information on my findings drop me a message. Im more likely to reply on instagram @eds.hacks