Spin-axis stabilization of an underactuated accompanying satellite around the space station

Paper number

IAC-06-C1.2.04

Author

Dr. Fang Wang, China Academy of Space Technology (CAST), China

Coauthor

Dr. Honghua Zhang, Beijing Institute of Control Engineering, China

Year

2006

Abstract

This paper deals with the spin-axis stabilization of an underactuated accompanying satellite around the space station in the presence of sinusoidal disturbances. The concept of accompanying satellites(AS) around the space station(SS) is introduced. Both the AS and the SS are modeled as rigid bodies, with the reference coordinate frames described for the AS pointing to the SS. When actuators in one dimension are failed, the AS has only two independent control torques and becomes an underactuated spacecraft whose attitudes can’t be controlled conventionally.
  There are many studies on the underactuated rigid spacecraft, however, all of them are focused on the attitude stabilization of the underactuated system without considering some external disturbances. The novelty of the problem posed here is that the disturbance torque induced by the flexible components of the AS and the aerodynamic drag is included in the attitude dynamics. Without loss of generality, the disturbance is assumed to be periodic in time described by sinusoidal function with the initial conditions unknown. The problem of the attitude stabilization of the underactuated AS in the presence of sinusoidal disturbances is complex, so the paper only deals with the case of the spin-axis stabilization of the underactuated AS.
  The purpose of this paper can be stated as finding a globally asymptotic stable control law so that in the presence of sinusoidal disturbance, the spin-axis of the underactuated AS is stable, where it can achieve suitable attitude in accordance with the expected thrust direction before orbit maneuvering and then attain reorientation towards the desired direction (e.g., the SS) after the orbit maneuvering. 
Based on the above purpose, the paper first introduces the control model of the underactuated AS using the (w,z) parameterization, then investigates the controllability of the model. Since the underactuated rigid spacecraft can’t be controlled through a continuous time-invariant state feedback, the paper investigates a time-varing periodic controller. The analytical and simulation results show that the proposed control law is effective in the presence of sinusoidal disturbance. 
  Spin-axis stabilization of an underactuated AS is useful in practice such as obtaining reorientation or inspecting the SS and its surroundings equipped with cameras; also, from a theoretical point of view, it is a valuable attempt towards the researches on the underactuated spacecraft in the presence of unknown disturbances.

Abstract document

IAC-06-C1.2.04.pdf

Manuscript document

IAC-06-C1.2.04.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.