The Stabilization of a North-Seeking Platform Using a Dynamically Tuned Hooke’s Joint Gyroscope

Abstract

The paper shows that the ideally tuned Hooke’s joint gyroscope is capable of operating as a gyrocompass. The dynamic response of the compass is examined in detail and its accuracy as a north-seeking device is assessed. It it shown that small amounts of mistuning will result in gross errors. The need for precision tuning is eliminated by supporting the gyroscope on a single-degree-of-freedom platform. It is shown that if the platform is driven via feedback of the gyrorotor displacement in azimuth then the response of the combined system is essentially that of the ideal gyroscope. The overall system is insensitive to misturning errors and will automatically align the gyrospin axis with true north irrespective of any initial offset. The effects of damping, mass unbalance, and platform misalignment are assessed.