Simulation analyses on ballistic limit of interior equipment behind spacecraft structure wall

Themeteoroid and increasing manned orbital debris have been a serious threat to spacecraft in Earth orbit because it can collide with spacecraft at extremely high velocities and consequently damage mission-critical systems. Many work has been done to assess the protection capability of spacecraft structure walls and shields, but generally, the protection capability of interior equipment (i. e. tanks, heat pipes, high pressure vessels, electronic boxes, batteries, harness) behind spacecraft structure wall was not considered. Hypervelocity impact simulations for equipment casing are implemented in this paper to acquire the ballistic limit curve (BLC) of interior equipment and calibrated by hypervelocity impact tests of ATV samples. The results prove that hypervelocity impact simulation is valid for studying the orbital debris protection capability of spacecraft structures and, if the inherent protection capability of spacecraft equipment against hypervelocity impacts is explicitly considered, the critical projectile diameters for failure of such equipment are raised considerably compared to the case where equipment is assumed to fail as soon as the structure wall that protects it is perforated.