On-Line Mass-Property Identification Algorithm Research for Satellite

The purpose of this paper is to identify the mass property of satellite under thrusters control on-line. Spacecraft control, state estimation, and fault-detection-and-isolation systems are affected by unknown variations in the vehicle mass properties. It is often difficult to accurately measure inertia terms on the ground, while mass properties can change on-orbit as fuel is expended, the configuration changes, or payloads are added or removed. Mass property identification is achieved through recursive least squares algorithms here, only based on gyro signals and thruster outputs. The approach addresses the issue by segmenting the problem into two sub-problems which both allow closed form solution. Implementing both recursively, and with each solution using the results of the other one to minimize the bias due to coupling. Simulation results indicate that this approach is simple and effective. The proposed solution is suitable in on-board real-time computation.