The Effect of Manufacturing Errors on the Performance of a Gas-Dynamic Bearing Gyroscope

Abstract

The purpose of this paper is to investigate the effect of manufacturing errors on the performance of a gas-dynamic bearing gyroscope. Five kinds of manufacturing errors including bearing taper error, oval error, trigone error, eccentricity of the axis, and angular deviation of the axis are studied. A mathematic model of these errors is established to describe the variation of gas film thickness. The Reynolds equation is solved, and the perturbation method is applied to analyze the performance of the gas-dynamic bearing with the manufacturing errors. Based on the analysis, the interference torque and overload limit are investigated to assess the effects of manufacturing errors. Results show that taper error will cause interference torque. Oval error or trigone error will cause interference torque with a radial specific force. The eccentricity or angular deviation of the axis will cause interference torque with any specific force. In general, the interference torque is small, which is 10–1000 times smaller than that under the condition of both radial and axial specific forces. The manufacturing errors also reduce the ultimate overload significantly. The taper error has the greatest influence on the gas-dynamic bearing gyroscope among the manufacturing errors studied in this paper.