Modeling and Analysis of Drift Error from Stator of A MSSG with Double Spherical Envelope Surfaces

Abstract

-For the newly developing magnetically suspended sensitive gyroscope (MSSG) with double spherical envelope surfaces, it is necessary to analyze the causes of drift error to improve sensing accuracy. This paper builds the models of disturbing torques generated by stator assembly and process errors based on the geometric construction and running regularity of the MSSG, and further reveals the generation mechanism of the drift error. Then the drift error from a single stator magnetic pole is calculated quantitatively with the established model, and the key factors producing the drift error are further discussed. It is proposed that the main approaches in reducing the drift error from stator are guaranteeing the rotor envelope surface to be an ideal spherical and improving the controlling precision of rotor displacement. The common problems associated in a gyroscope with a spherical rotor can be effectively resolved by the proposed method. This analysis provides a reference for the structure optimization and error compensation of a MSSG.

Adaptive robust sliding mode simultaneous control of spacecraft attitude and micro-vibration based on magnetically suspended control and sensitive gyro

“…Since the MSR deflection of MSCSG is generated by Lorentz Force-type magnetic bearings (LFMB) which avoids the drive delay and mechanical friction, the micro-gimbal torque output by MSCSG has higher accuracy and bandwidth than that of MSCMG. Besides, since the rotor of MSCSG has a double spherical structure, 19 the rotor deflection range is larger than that of MSCMG and the translational and rotational modes of the rotor are completely decoupled, which means MSCSG has the ability to suppress vibration of larger amplitude and has higher vibration suppression accuracy. Further, the measurement precision of spacecraft attitude can be improved by making full use of the dynamic information of the MSCSG configuration.…”

“…18 However, the complicated situations such as difficult measurement of micro-vibration, unknown moment of inertial of spacecraft and parameter changes have not been considered in the earlier study. 14–19…”

“…18 However, the complicated situations such as difficult measurement of micro-vibration, unknown moment of inertial of spacecraft and parameter changes have not been considered in the earlier study. [14][15][16][17][18][19] This paper proposes a synchronous control method of spacecraft attitude and micro-vibration based on MSCSG. The attitude control and vibration suppression of spacecraft are realized simultaneously by the gimbal rotation and rotor deflection of MSCSG.…”

Stability analysis for a rotor system in a magnetically suspended control and sensitive gyroscope with the Lorentz force magnetic bearing rotation

“…A spacecraft attitude control system consists of attitude sensors, attitude controllers and actuators. 1,2 A rotor-type rate gyroscope plays the role of the attitude sensor, and a control moment gyroscope or flywheel plays the role of the actuator; both of these instruments are inertia devices. 3,4 If these devices are integrated into a single device, then the volume weight, power consumption and cost of the attitude control system will be significantly reduced.…”