µC control of a force testing machine
You could use a microcontroller, but as mentioned, a PLC would be a better way to automate this, or perhaps a motion-control gizmo such as are made by Galil.

You don't want a current DAC so much as a motor driver that'll take whatever signal is produced by your PLC (probably a voltage) and command a current to the motor.

Galil motion control or National Instruments* should be able to recommend a path forward, by buying stuff from them at what would be a staggeringly high price if you were developing a product, but which should (if you use the stuff right) save you way more money in engineering time than you spend on them.

* Whom I recommend as I cringe, because I don't like they way they think - but if you ever hire a manufacturing engineer, they'll be very happy with the setup.