Abstract: In an accelerometer in which a proof mass is disposed in a damping fluid and acts against said fluid through a flow path controlled by the groove length of a helix disposed on a bellows, a low resistance flow path is provided connecting the areas above and below the helix to prevent movement of the proof mass due to fluid displacement caused by rapid temperature changes.

Abstract: A gyro seeker which may be employed and housed in the nose section of a cannon launched missile. The gyro seeker functions in a dual mode in that it detects either laser designated targets or targets emitting infrared radiation. Structurally, the gyro seeker comprises a spherically shaped gyro element hydrostatically supported on a gas bearing surface within a spherical cavity of a spherically shaped platform. The gyro in turn supports optical and detector/cryostat assemblies for tracking and detecting desired targets. The platform is similarly hydrostatically supported on gas bearings within the housing. The platform is restrained on the base of the missile by a trapeze mechanism which limits the platform to two-degrees-of-freedom. Means are provided for torquing both the gyro and the platform. Additional means are provided to allow the gyro seeker to withstand the high induced acceleration forces of cannon launching.

Abstract: A force rebalanced accelerometer utilizing a spherical proof mass disposed in a fluid and in which fluid pressure pulses developed by positive displacement pump are used to balance inertial forces.