Thermal Vacuum and Swivel Table Tests of a CMG and Fault Mechanism Analysis

Abstract

Thermal vacuum and swivel table tests of a control moment gyroscope (CMG) are designed and the start-up hesitation and rotation break of the CMG are analyzed. In order to study the fault mechanism, a thermo-structural coupling simulation was performed on the CMG under the temperature conditions of 6°C and approximately 2°C, as well as the static and dynamic working conditions of the swivel table and gimbal. The simulation results show that the main reason for the start-up hesitation and rotation break of the gimbal is an elliptical deformation in different circumferential positions of the gimbal shell and the gimbal bearing. Under certain combinations of temperature and dynamic conditions, the shrinkage of the radial and axial clearances of the gimbal bearing causes the faults, which is consistent with the test results. The test and simulation results are also helpful in determining the temperature limits of the CMG under different conditions and can help improve their thermal design.