Abstract: Suspension stiffness about the input axis of a gyro is increased by selectively disabling suspension legs when the gyro float exceeds a predetermined deviation away from the equilibrium position. Float position may be measured directly or inferred from monitoring currents in the electromagnetic suspension system. Suspension legs are re-energized when the float returns to within the predetermined deviation from the equilibrium position.

Abstract: Disclosed is apparatus and method for accurately determining the direction of true north or the change in drift of other gyroscopes. The apparatus comprises a single degree of freedom gyroscope driven by a permanent magnet electric motor. The gyroscope rotor is spun by the motor at varying speeds and the torque required to maintain the rotor at a null orientation is measured and recorded. The measured torques are processed to produce an accurate indication of true heading or to indicate the change in the level of drift of other gyroscopic instruments.

Abstract: An eliminator of vaporized contaminants from gas in a closed system in which high pressure gas is subjected to a substantially adiabatic expansion with accompanying temperature drop at a point where the contaminants cannot cause problems. In the specific case of a gas bearing, contaminants which normally condense in the gap between bearing surfaces are caused to condense at points well removed from the bearing gap where they cannot cause failure of the gas bearing. A remotely located expansion chamber or zone is created and it may include a restricting orifice at the inlet to which gas pressure is relatively high and at the outlet of which pressure is significantly lower. The pressure drop is accompanied by a comparably large decrease in temperature to a point at which the vaporized contaminants condense. A filter may be included at or adjacent to the outlet to trap the condensed contaminants.

Abstract: A method and apparatus for reducing the friction in a ball-bearing pivot axis assembly. Within the bearing assembly, the balls are floated in a fluid lubricant and, especially in fully-floated units, the weight of the balls is an overriding consideration in the generation of sliding frictional torques. In the present invention these gravitational effects are counteracted by matching as nearly as possible the ball density and the flotation fluid density, the floated weight decrease serving to bring down the friction proportionally with an ultimate theoretical complete reduction of frictional uncertainty from that of known systems.