I am trying to build a robotic arm that needs to lift a very low amount of weight (between 0.01-0.05kg) at a time, but it needs to be very precise (+/- 1mm accuracy ideally). The robot really only needs to have 3 DOF and the arc is roughly 0.5 meters. Additionally, the robot doesn't need to be very fast, only around 0.2-0.5 m/s is necessary.
What type of actuator would be the best suited for this kind of task, and what other factors would I have to consider? Do I need to spend more money for high quality servos, or can the task be done with hobby/RC servos with some modifications?