Bare Photovoltaic Tether characteristics for ISS reboost

This study focuses on designing a bare photovoltaic tether (BPT) for maintaining the International Space Station (ISS) orbit using a zig-zag strategy that was conceptually introduced in a recent previous work. This strategy involves alternating reboost maneuvers and natural decays due to atmospheric drag. The BPT characteristics, including total length, photovoltaic cell coverage of the tether/tape, and cell efficiency are crucial for an effective system operation. These characteristics are determined by an optimization process and the system effectiveness is evaluated by using FLEXSIM, a simulation software package capable of modelling ISS orbital dynamics during BPT operations. The simulations consider the semimajor axes for starting and ending BPT operations and incorporate the Lorentz Force generated by the tether/tape during reboost maneuvers. During the decay phases, the BPT is not operational, it is retrieved back and only gravity and neutral drag are acting on the system. The numerical simulations are used to validate the BPT system design for the ISS station-keeping maneuvers. Consequently, the goal of this paper is to showcase the feasibility of implementing this novel, sustainable, and environmentally friendly use of BPT technology to benefit the ISS station keeping, creating a fully autonomous system capable of independently generating the necessary input power to produce the Lorentz force necessary to carry out that task.