Angular-Momentum Management of Electromagnetic Formation Flight Using Alternating Magnetic Fields

摘要

An electromagnetic formation flight uses electromagnetic force to control the relative position of satellites and enables formation flying without consuming fuel. When an electromagnetic field is used, an electromagnetic torque is created that acts on the satellites, resulting in the buildup of angular momentum via reaction wheels or control moment gyroscopes. This paper presents a new angular-momentum management algorithm to solve the angular-momentum buildup problem using the Earth's magnetic field. The proposed method is characterized by combining an alternating electromagnetic field with a constant electromagnetic field. The alternating component is applied to regulate the relative positions of the satellites in the formation, whereas the constant component interacts with the geomagnetic field to reduce excessive angular momentum. With this method, angular-momentum management is decoupled from position control, and several restrictions are removed. A feedback-filter method is proposed to address the high uncertainty caused by the alternating electromagnetic field, and a sliding-mode controller is used to track the trajectory of both translational and attitude movements. The simulation results presented in this study demonstrate the validity and performance of the proposed strategy.