Sorry if this is answered elsewhere but google-fu failed me. Am trying to use Arduino to control a motor that will be hooked up a manual lab stage (this one http://www.zolix.com.cn/en/prodcon_371_385_536.html) controlling one of the micrometers. This is an effort to get a cheap alternative to the motorised stages (about $4000). I have a freetronics experimenter's kit and have gone through all the exercises, which includes a little servo. Theoretically what I want to do seems easy but I need a motor that turns relatively slowly but fairly precisely. Even with code that increments the servo small amounts at a time it doesn't seem to be predictable. I also bought a little Tamiya motor+gearbox (https://www.jaycar.com.au/2-shaft-universal-motor-gearbox-set/p/YG2742) which seems to output at the speeds I want but I can't figure out how to hook up a transistor to have Arduino control it (tried directly powering it from the board but that's too weak). I have made a circuit using a transistor controlling a LED brightness (via PWM) but that doesn't seem to work for the motor. Do I need a motor shield? TLDR: how best to control a slow speed motor with arduino (for a dummy).