Damage State Estimation for Reusable Spacecraft under Complex Stress

Reusable spacecraft have become one of the hottest research focuses in recent years as a result of their economic benefits and application potentials. Differing from the conventional ones, reusable spacecraft faces damage state estimation before relaunch. This paper proposes a novel damage state estimation method for reusable spacecraft experiencing complex stress loading processes. Based on analysis of life distribution and residual strength distribution, the characteristic life of the critical spacecraft structure is related to the working stress. Then working time under different stress levels is converted into working time under normal stress conditions through equivalent time calculation. Damage state estimation is achieved using the total equivalent time, and residual life is predicted and reliability is assessed. An illustrative example demonstrates the validity of the proposed method. The results indicate that this method can be conveniently used for damage state estimation for critical structure of reusable spacecraft.