On-line identification of spacecraft moment of inertia

In order to fulfill the reliable and efficient high precision attitude control, it is necessary to know the change of the mass property accurately, which makes the online identification of the moment of inertia become very important. With flying wheel as the execution unit, an open-loop and closed-loop moment of inertia identification method based on least recursive squares, an algorithm was proposed respectively. When the output control torque of the flying wheel is suitable, the open-loop spacecraft moment of inertia can be identified quickly, while the change of the spacecraft attitude is accepted. A closed-loop identification method was discussed based on variable structure controller. The spacecraft moment of inertia can be obtained rapidly while it completes the attitude motivation task, and the precision of the closed-loop identification can be within 2%.