Estimating the inertia tensor of the International Space Station on the base of the telemetry information

The paper presents the method and the results of estimating the inertia tensor of the International Space Station on the base of the telemetry information about its attitude motion and the total angular momentum of gyrodines. The information about an attitude motion contains values of the quaternion of the station attitude with respect to an inertial coordinate system at some instants. Basing on the information, we reconstruct the station motion using splines or Fourie series. Such an approximation is used in the linear differential equations, which describe the variation of the total angular momentum of gyrodines during the motion. Solutions of the equations depend linearly upon inertia tensor components and station aerodynamic parameters. We find estimations of these quantities from the condition of the best approximation of angular momentum measurement data by those solutions using the least squares method. The method was applied for processing real telemetry data. The errors of estimating the diagonal (the most large) inertia tensor components were in limits of 10–20 percents.