Damage Assessment for Electrodynamic Tape Tether against Space Debris Impact

Abstract

Space debris has become a great concern within the field of space development. In particular, one active debris removal method involves the use of an electrodynamic tether system that exploits the interaction between the geomagnetic flux and plasma electrons. Among the various tethers, tape-shaped tethers show superior survivability during debris removal missions. However, a concentration of stress may be generated at the edge of a damage hole caused by debris collision, resulting in crack advancement and severance of the tethers. Here, we propose an aluminum glass cloth tape (ALGC) tether, in which stress is uniformly distributed. To simulate space debris collisions with tethers, hypervelocity-impact experiments are conducted using a two-stage light-gas gun at ISAS/JAXA. First, lengths of circular or elliptical damage holes are measured and compared between two types of tethers, ALGC tethers and standard aluminum tape tethers. Next, their severance characteristics are defined in terms of tensile force. Additionally, collision simulations are conducted for aluminum tape tethers to allow a detailed comprehension of debris collisions. It is confirmed that, even in the case of two tethers with nearly equal damage dimensions, ALGC tethers outperform aluminum tape tethers in terms of tolerance to tensile force. These versatile ALGC tethers overcome the disadvantages of aluminum tape tethers and should thus exhibit high survivability against debris collisions during removal missions.