Simplified technique for reconstructing spacecraft attitude motion by processing onboard measurements of the angular rate and the strength of Earth magnetic field

Reconstruction of the attitude motion of the spacecraft Bion M-1 and Foton M-4 was made by sufficiently detail and exact mathematical model (KIAM preprints No. 2, 2014 and No. 8, 2015). The model used for processing onboard measurements of the strength of the Earth magnetic field and the spacecraft angular rate. If we will slightly reduce accuracy requirements, we can greatly simplify the processing technique. The simplification consists in refusal of specification of the shifts in angular rate measurements. This reduces the calculations at minimization of the functional of the least squares method, the most complicated part of them being fulfilled by the standard procedure of computational linear algebra. We describe the simplified technique by the example of reconstruction attitude motion of the spacecraft Foton M-4. The noticeable difference between results obtained by the new technique and the more exact old one becomes apparent at processing measurements in time interval more than 4 hours.