Mass property estimation of gyroless spacecraft

This paper presents the design of algorithms to estimate the mass property, specially the moment of inertia, for the gyroless spacecraft. The gyro has several problems such as high price and frequent breakdown, but the other sensors could not replace gyro because of its update rate. However, CMOS-APS-based star tracker which is recently developed can give the vector observations in high update rate and gyro does not need to be installed on the spacecraft. Thus, this research builds algorithms to estimate the moment of inertia only using vector observations in real time. Kalman filter are mainly used and the least square method is applied to calculate the angular rate from the star vectors. The simulation results are also discussed to verify the validity of the designed filter.