Utilisation of the Controllable Inertial Morphing for Providing Spacecraft with Acrobatic Attitude Capabilities.

Abstract

The paper is exploring a new method of controlling of the attitude dynamics of the spacecraft with non-zero angular momentum, using deliberately applied changes to the spacecraft inertial properties, called inertial morphing (IM). This method does not employ classical gyroscopic devices, nevertheless it enables the spacecraft to perform various acrobatics manoeuvres, allowing interchanges between stable and unstable states. In one case scenario, it enables transformation of the stable spin into unstable flipping motion and establishment of the desired periods of the flips at various stages of the procedure. Special consideration is given to the selection of the controllable morphed parameters to impose the desired periods and patterns of the acrobatics. This paper exploits use of the unstable flipping motions of the systems and due to established mini-max relationships for the flipping periods, enables selection of the system parameters, maximizing or minimizing the values of the periods for faster (more agile) maneuvers. In the other scenario, IM is used to transfer the regular spin about one body axis into the regular spin about another nominated body axis. Numerous illustration cases are presented and application of the new enhanced capabilities are discussed in detail. For example, paper presents a scenario of the reconfiguration of the articulated spacecraft with its segments being inverted during the acrobatic procedure in the desired way, which may open new possibilities during the spacecraft operation, including re-boost and landing.