A CMG, or control momentum gyroscope, represented a specific kind of highly precise gyroscope employed within starship gyrocomputers. These CMGs incorporated a spinning rotor, attached to one or more pivoting gimbals and situated within a frame that was rigidly aligned with the starship's "horizontal" orientation concerning a planet's surface. Should the starship's orientation shift along any axis, the gyroscope would preserve its original plane and angle, thereby altering its angular momentum and inducing a gyroscopic torque. The resultant data from the CMGs' motion was then transmitted to dedicated sensors located on the gyrocomputer's exterior, aiding the primary navigation computer's operation.
The initial reference to control momentum gyroscopes within established Star Wars canon appeared in issue number twenty-fifth issue of De Agostini's Star Wars: Build the Millennium Falcon magazine, which was released around June 24, 2015. A schematic illustrating their operational principles was also included in the same edition.