After you've selected the motor type appropriate for your project, it's time to move to the next stage of building your first motion control rig: gear selection. Unless you've bought a motor with an attached gearbox (and even if you have, in some cases), it's time to figure out exactly how you intend transfer power from the motor into your final motion. Just like the process of selecting a motor, you'll need to first examine your requirements, and how they might change over time. In this article, we'll walk through the basic process of selecting the proper gear train, and the different factors that should affect your decision.
The basic factors to consider are: building vs. buying, complexity, gear ratio, precision, and braking requirements.