Attitude control of spin-type space membrane structures using electromagnetic force in earth orbit

Abstract

This research proposes a novel attitude control method for a membrane structure that uses electromagnetic torque while in Earth orbit. A spin-type membrane structure with a satellite’s body at its center is lightweight and highly compactible, enabling the realization of systems that require a large surface area. The attitude control of such a structure poses an issue because of a relatively large angular momentum of the membrane, requiring a large torque to shorten attitude control duration. Moreover, application of this torque to both the body and membrane is desired to prevent vibration on the membrane. A typical method using reaction wheels and thrusters applies a relatively large torque only to the body, which requires propellant consumption. Another method using solar radiation pressure applies torque only to the membrane, resulting in a weak torque. Thus, conventional methods cannot achieve a sufficiently large torque applied to both the body and membrane without extraneous propellant consumption. In the proposed magnetic attitude control method, the electric current flowing along the edge of the membrane and the magnetic torquers in the body interact with the Earth’s geomagnetic field and generate a large, controllable electromagnetic torque applied to both the body and membrane, which enables a large torque without consuming propellant. This research evaluates the performance of the proposed method in terms of the attitude maneuverability and vibration of the membrane using numerical simulations. Specifically, this research investigates the effects of the electric current, spin rate, and orbit inclination, which are related to the strength and direction of the electromagnetic torque. A dynamics model of the numerical simulations is derived from the multi-particle method. The numerical simulations reveal that the proposed method induces a larger torque compared with that by solar radiation pressure, improving maneuverability. This maneuverability is related to the electric current intensity and the orbit inclination. The vibration caused on the membrane during the attitude control is small; the maximum amplitude is only 3.1% of the membrane size. This amplitude decreases as spin rate increases because of geometric stiffness. Based on the results, this research concludes that the proposed method is technically feasible and contributes to the actualization of a large membrane structure.