Sensitivity analysis of spacecraft in micrometeoroids and orbital debris environment based on panel method

To reduce the risk of mission failure caused by the MM/OD impact of the spacecraft, it is necessary to optimize the design of the spacecraft. Spacecraft survivability assessment is the key technology in the optimal design of spacecraft. Spacecraft survivability assessment includes spacecraft impact sensitivity analysis and spacecraft component vulnerability analysis under MM/OD environment. The impact sensitivity refers to the probability of a spacecraft encountering an MM/OD impact while in orbit. Vulnerability refers to the probability that each component of a spacecraft may fail or malfunction when impacted by space debris. Yet this paper mainly analyzes the impact sensitivity and proposes a spacecraft sensitivity assessment method under the MM/OD environment based on a panel method. Under this panel method, a spacecraft geometric model is discretized into small panels, and whether they are impacted by MM/OD or not is determined through the analysis of the shielding or shadowing relationships between panels. The number of impacts on each panel is obtained through calculation, and accordingly the probability of each spacecraft component encountering MM/OD impact can be acquired, thus generating the impact sensibility. This paper extracts data from the NASA's ORDEM2000, the ESA's MASTER8 as well as the SDEEM2015 (Space Debris Environmental Engineering Model developed by HIT), and uses the PCHIP (Piecewise Cubic Hermite Interpolating Polynomial) method to interpolate and fit the size-flux relationship of space debris. Compared with linear interpolation and cubic spline interpolation, the fitting results through the method are relatively more accurate. The feasibility of this method is also demonstrated through two actual examples shown in this paper, whose results are close to those from ESABASE, although there are some minor errors mainly due to different debris data input. Through the cross-check by three risk assessment software - BUMPER, MDPANTO and MODAOST - under standard operating conditions, the feasibility of this method is again verified.