Monitoring of Accelerations Onboard an Oriented Spacecraft

Monitoring of accelerations onboard previous spacecraft of the Foton series was realized in the following ay. First we reconstructed a real spacecraft attitude motion in a time interval of interest by measurements of onboard sensors. Then we calculated an acceleration at a given point of the spacecraft body along the found motion by the well-known formula. The attitude motion was represented by a solution of spacecraft motion equations. The equations were rather simple and accurate because the motion of Fotons was uncontrolled. The motion of new Fotons will be controlled by CMG or flywheels. Much more complicated mathematical model should be used for a detailed reconstruction of such a motion. The models have to include the equations of the proper spacecraft motion and the equations describing the operation of the control system. We propose in this paper to use the reduced models for reconstructing the oriented motion. The models are intended for reconstruction of the motion in the low-frequency range by smoothing Kalman's filter and for calculation of quasi-steady accelerations. The adequacy of the proposed approach is tested by reconstructing the oriented motion of Foton M-3 and by processing the model information calculated for the worked out spacecraft.