Abstract: A gyro rotor is freely suspended in a housing for simultaneous rotation about a spin axis and a pair of precession axes in turn orthogonal to the spin axis, by a pair of magnetic suspensions spaced along the spin axis. Each magnetic suspension comprises a magnetically permeable stator member and a cooperative magnetically permeable rotor member relatively arranged so as to define axially spaced annular magnetically permeable gaps. Each magnetic suspension includes a permanent magnet for producing a fixed or passive magnetic flux in each gap and an electromagnet coil for producing a controllable or active magnetic flux in each gap. The passive flux provides passive stabilized suspension of the rotor parallel to two of said axes, while the active flux provides active stabilized suspension of the rotor parallel to the third of said axes using a closed servo loop.

Abstract: A magnetic bearing assembly for levitating a movable member in either rotation or linear translation comprises a three-loop magnetic circuit in which permanent magnets establish a quiescent or fixed flux across four magnetic gaps arranged to provide restoring forces transverse to the direction of gap flux; the resulting inherent instablity in the longitudinal direction is overcome by an electric feedback control system which supplies control currents in a pair of coils associated with the magnetic gaps for modulating the permanent magnetic flux therein and thereby provides stabilizing longitudinal magnetic forces. The magnetic core, permanent magnet, and coil configuration permits a modification to the electric feedback control system whereby the transverse restoring forces may be controlled to provide transverse stiffness augmentation.