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Indexed by:期刊论文

Date of Publication:2018-08-01

Journal:PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE

Included Journals:SCIE

Volume:232

Issue:16

Page Number:2850-2860

ISSN No.:0954-4062

Key Words:Platform inertial navigation; three-floated gyroscope; gas lubrication; conical bearing; static error model

Abstract:Three-floated gyroscope with the advantages of high accuracy has been widely used in platform inertial navigation system. To investigate the influence of specific force on the measured angular velocity of a gyroscope with a rotor supported on gas-lubricated bearings, a static error model considering three-degrees-of-freedom displacement of the rotor is proposed through numerical computation. Firstly, the conical Reynolds equation incorporated with the Fukui and Kaneko's slip model is adopted and solved by the finite difference method, and the bearing force, caused by specific force, are obtained for each rotor displacement. Secondly, the error of gyroscope measured angular velocity is calculated from bearing force and rotor displacement. Finally, the relationship between the error and specific force is obtained by regression analysis, and the static error model of the gyroscope is proposed. To simplify the ternary regression analysis to binary, two intermediate parameters, radial interference torque and circumferential angle between interference torque and specific force, are introduced. Numerical results show that interference torque is approximately /2 ahead of specific force in circumferential direction with f(z)>0, and /2 behind specific force with f(z)<0, and that a large interference torque is produced when the specific force in radial and axial direction are both large. The error model provides a rapid prediction of the error caused by rotor displacement by three-degrees-of-freedom specific force.