Attitude Control of a 2U Cubesat by Magnetic and Air Drag Torques

Abstract

This paper describes the development of a magnetic attitude control subsystem for a 2U cubesat. Due to the presence of gravity gradient torques, the satellite dynamics are open-loop unstable near the desired pointing configuration. Nevertheless the linearized timevarying system is completely controllable, under easily verifiable conditions, and the system's disturbance rejection capabilities can be enhanced by adding air drag panels exemplifying a beneficial interplay between hardware design and control. In the paper, conditions for the complete controllability for the case of a magnetically controlled satellite with passive air drag panels are developed, and simulation case studies with the LQR and MPC control designs applied in combination with a nonlinear timevarying input transformation are presented to demonstrate the ability of the closed-loop system to satisfy mission objectives despite disturbance torques.

Servi̇s Küp Uydusunun Bulanik Denetleyi̇ci̇ Kulanilarak Hedef Küp Uyduya Yönlendi̇ri̇lmesi̇

“…Ülkemizde de üniversiteler ve özel kuruluşlar başta olmak üzere birçok kurum tarafından da küp uydu çalışması yapmış, tasarımı yapılmış ve uzaya gönderilmiştir. [1], [2].…”

A review of balancing methods for satellite simulators

“…When simulating 3D rotational movements, a simulator may present pendulum-like motion, as a consequence of the unbalance produced by the distance between the Center of Rotation (CR) and the Center of Mass (CM) of the platform. In order to properly repro-30 duce attitude maneuvers in the Low Earth Orbit (LEO), for example, this torque should be reduced to values as low as 10 −6 N m [11,12,13].…”

Tube-Based Model Predictive Control Of Small Satellite Systems With Uncertainty Dynamics

“…In addition, control for small spacecraft, like smallsats or CubeSats, is a developing research area due to hardware limitations, actuation constraints, and susceptibility to disturbances [12,13]. Current MPC applications on satellite systems have considered momentum management, satellite docking, and attitude maneuvering with respect to large angles and constrained attitude [14,15,16,17,18]. However, research using tube-based MPC has been limited to orbital maneuvering [19,20,21].…”