Hi,
Using either I2C or (better) SPI (simple implementation, a few bits of discreet hardware and a few reuseable subroutines), you could build a system where the master commands eg.: "UID, turn steering 30° left".
The steering controller then starts turning and when the position is reached, sends a "UID, Acknowledge" and stays there until told differently.
(Where "UID" is the Unique ID for the steering, but each sub-module should have one of course, while sensors should do interrupts directly - polling would defy the entire principle of master/slaves processing).
I have been using that in a servosystem where the feedback was from a 1°/step Gray-coded disk (read via light fibers).
Now, I don't know what you view as precision, or the size of what you have in mind, so more precise advice is hard to give (the usual punishment for not giving the info needed
).
Master/slaves processing is not needed in the average robot, but it sure helps modularizing as well as trouble shooting