Autonomous Stabilization of a Spacecraft Orbital Orientation at the Lack of Angular Velocity Measurements

We consider applying a full order dynamic observer to stabilization of spacecraft orbital orientation by means of flywheel engines with only infrared vertical measurements available (angles of roll and pitch). It is shown that linear observer defines the estimations of lacking parameters of angular motion (angle of yaw and three angular rates), and at certain features of a control algorithm these estimations may be used for stabilizing the full non-linear model. We introduce such features of linear algorithm of control that, despite the weak physical relation of the yaw channel with other control channels, allow adequate estimating the dynamic parameters (angle and angular rate) in this channel and keeping stability of the full non-linear model of spacecraft controlled motion. By the results of mathematic simulation for the typical artificial satellite of the Earth, the values of controller and observer poles are determined reducing the duration of transient to build the orbital orientation.