Fault Isolation and Identification of a Four-Single-Gimbal Control Moment Gyro On-board a 3-axis Stabilized Satellite

Control moment gyros are known for their applications in attitude stabilization. These actuators are susceptible to malfunction, which results in faults and failures. Therefore, diagnosing the faults can improve the reliability of completing a mission while reducing maintenance costs. Thus, a model-based fault diagnosis method is proposed here. The intended algorithm is an enhanced version of previous work by the author. The enhancement employs a condensed approach to alleviate the delay caused by the filter’s confidence in its estimations. A case-study on a closed-loop controlled satellite is provided along with an extensive Monte Carlo simulation to evaluate the proposed method’s performance. The results show that the enhanced method can achieve superior performance while requiring less computational resources by eliminating extra grid search loops.

Design of control moment gyro electric drive with strict requirements on ensuring desired rotational velocities

The paper discusses the issues of designing a control moment gyroscope electric drive with strict requirements in terms of the accuracy of ensuring a given rotation rate of the gyro motor suspension. A brief description of the control moment gyroscope electric drive applied currently is presented and the issues of improving the electric drive characteristics are discussed. As a solution, an electric drive is proposed which operates in the mode of feedback loop using angle sensors located on the axes of the gyroscope suspension and the engine rotor. The paper describes the arrangement of the control moment gyroscopes on advanced spacecraft for Earth remote sensing and presents the analytic expressions needed to calculate the control moments that affect the spacecraft. The moments are in the projection to the coordinate system brought into coincidence with the spacecraft. The paper compares spacecraft angular velocity stabilization errors for the cases of using the conventional scheme of control moment gyroscope electric drive and the newly developed one. The presented results can be used for developing control moment gyroscope electric drives to be mounted on spacecraft of different purpose with strict requirements on ensuring operation at specified rotational velocities.