Abstract:  Due to the influence of factors such as fuel consumption and structural thermal deformation, the mass distribution of the space-based gravitational wave detection spacecraft will change, and the position of the center of mass will be offset, which will seriously affect the accuracy of gravitational wave detection. Aiming at the demand of high-precision measurement of center of mass for the space-based gravitational wave detection spacecraft, a spacecraft center of mass identification method based on periodical micro incentives is proposed. First, a spacecraft dynamics model that takes into account the effects of nonconservative forces in space, gravity gradient forces and thruster noise is constructed. Then, the research on inertia tensor identification method based on space inertial sensor and star sensor measurement data, and the input method of periodic micro incentives based on thrusters are conducted. A center of mass identification method based on periodical micro incentives and Kalman filter theory is proposed. Finally, simulations under different waves of incentives are carried out. The results show that under the moment of the triangular waveform, the present method is able to achieve high-precision centroid identification with a resolution of 2.14×10^-6m during an extremely small angular maneuver of 2.2×10^-5rad. This research can reduce the cost of interplanetary link reconstruction and provide a technical approach to maintain the accuracy of spacecraft detection.

Key words: identification of center-of-mass, gravitational wave detection spacecraft, periodical micro incentives, non-conservative force, Kalman filter