ABSTRACT
Deep drilling systems in extra-terrestrial environments are crucial in scientific discoveries. It is planned to collect a sample core from lunar surface, and designing appropriate drilling systems requires knowledge of forces and moments encountered. A comprehensive analytical model for estimating drilling forces is desired, and in this paper, existing literature on soil failure theories as well as transport theories are consulted to arrive at such a model. The practice of drilling in batches to obtain multiple cores is also evaluated from a drill design perspective.
