Three dimensional finite element analysis of inertial gyros

An analytical approach to the prediction of gyro error torques due to structural and thermal effects has been developed based on the finite element method. The calculated strains and temperature distributions are employed to estimate drift coefficients. Example calculations are presented for a single-degree-of-freedom floated gyro. The structural loads considered include accelerations, torque-nut preloads and gas-bearing pressure. Deflections computed by the finite element program are used to calculate the major compliance coefficient, D(IS). Use of the results to minimize microcreep effects is also discussed. The same finite element mesh used for the structural analyses was employed in the heat-conduction calculations. The heat distribution to the float from the gas bearing wheel was varied to determine the sensitivity of float sleeve temperature to wheel-parameter variations.