Study and evaluation of tether-net parameters for space debris capture using modified capture quality index

Abstract

The increasing volume of space debris presents a significant threat to spacecraft safety and the long-term viability of space missions. Among the proposed methods for capturing and removing small space debris at low relative velocities, the tether-net method emerges as particularly promising. Identifying and evaluating the parameters influencing the capture process through simulations is imperative to ensure the effective capture of debris by the net and to assess its efficiency. Therefore this study investigates the influence and effectiveness of various parameter combinations through simulations. The study examines the effects of parameters such as net and space debris masses, shooting speed of the corner mass (CM), CM ejection angle, and activation or deactivation of the net mouth closure mechanism on the space debris-capturing capacity. The capture effectiveness evaluation was conducted utilizing the modified capture quality index ($MCQI$). During simulations where the closure mechanism was not activated, the net opened upon debris contact, resulting in expulsion and decreased $MCQI$. Conversely, activation of the closure mechanism enhanced the probability of capturing space debris. Within the “wrap” category, parameter combinations of medium CM ejection angles, extended initial distances, and high shooting speeds yielded the highest capture quality for debris capture, as confirmed by the $MCQI$. Conversely, a larger CM ejection angle and other parameters reduced the likelihood of debris capture, indicating an inverse relationship between the ejection angle and the initial distance between the net and the debris.