Roll Angular Momentum Enhancement of a Tethered Satellite System for Transfer in Different Orbit Plane

This paper discusses the in-planar and out-of-planar dynamics of a Tethered Satellite System (TSS), which aims to inject a satellite into a different orbit plane. The orbital transfer is achieved by only varying the tether length in a gravity gradient field. A previous work treating in-plane orbital transfer induces the system's pitch motion, and proposes a control procedure. For a transfer in a different orbit plane, the system's roll motion must be controlled as well as its pitch motion. First, this paper shows the system's governing equations of motion, and compares the features of the roll motion with its pitch motion. Then, a control method is proposed to increase the angular momentum of the roll motion. Finally, the effectiveness of the proposed method is demonstrated by numerical simulations.