Driving Gyroscopes: Systems for Keeping Disks Spinning

[SmashtheVan]

So I understand the applications of gyroscopes for measuring changes in orientation and the like. However, I always have struggled with the fact that the rotating disk in the gyroscope will eventually have to come to rest thanks to friction forces. This brings me to the assumption that there must be some restorative force(my guess is magnetic/electric/both) applied to keep the disk at a high rate of speed in real-world application.

can anyone help me out with a general description of the types of systems used to keep the gyroscope spinning, or can link me to resources that can help me out on this?

 

[russ_watters]

They are powered by electric motors.

 

[SmashtheVan]

I'd read that motors were used but was confused on how they were implemented. Since posting have been able to track down my answers