Torque problem in stepper motor Delta robot

Delta bot imageI have a three stepper motor for individual link and it connected via pulley driven by closed loop belt (not a linear rail type Delta )
Could you suggest a software and stepper motor driver for operating Delta pick and place.intially for the manual run i use the aurdino uno and three a3967 driver connections but it doesn't get enough torque sir while I test a manual run via cnc Sheid it runs perfect by individual motor , sir but I didn't know program .so could you suggest best solution for all the problems sir

Maybe a 'nautilus gear' system will help? It will change the torque from low at the beginning to high, when the levers raise. It also changes the kinematics from 'polar' to linear.

Edited 1 time(s). Last edit at 09/15/2018 04:00AM by o_lampe.