Stick-slip behavior of reversing the tubular woven bag covering a rigid tube-theoretical and numerical studies

Abstract

A tubular woven bag covering a rigid tube, known as a crucial component in flexible tube coring system adopted for future lunar soil coring missions, which dynamic performance, especially the stick-slip behavior, might largely affect the reliability and quality of the lunar soil coring, should be explored in depth. In this study, we have developed analytical formulation and high fidelity finite element (FE) model to investigate the stick-slip behavior of the tubular woven bag covering a rigid tube in the turning inward process. The theoretical model is established via dividing the whole process into the unfolding and the detaching periods. The FE model is efficiently established and solved by using nonlinear finite element code LS-DYNA. Results demonstrate that good agreement can be realized between the numerical results and the theoretical ones. Moreover, based on the developed theoretical model, parametric analysis of the stick-slip process is performed to quantify the effects of the key parameters, including the mass, damping and stiffness of the woven bag, the driving velocity, the pressure on the bag, and the initial wrinkle ratio, on the stick-slip behavior. The findings from this study can provide practical and important guidance for designing the deep lunar soil coring system with high stability and reliability. Keywords: Stick-slip behavior, Flexible tube coring system, Parametric analysis, Numerical simulation, Theoretical study