An improved inertia matrix identification method for nonlinear spacecraft model

The mass properties information is important for the control, state estimation and fault diagnosis of the spacecraft, however, it is often difficult to be accurately measured or calculated on ground and may also change in space due to the fuel consumption or structure changes. This paper proposes an improved inertia matrix identification method using the control torque input and attitude angular velocity output of the spacecraft attitude dynamic systems, which is independent of the controller form, and does not require specific command signals. Compared with the existing method, the proposed method can work well when the spacecraft rotates both slowly and fast. A numerical simulation example is presented to show the effectiveness of the method.