On Modeling Drilling Load in Lunar Regolith Simulant

Abstract

Drilling and coring, as effective ways to obtain lunar regolith along the longitudinal direction, are widely applied in the lunar sampling field. Conventionally, modeling of drill-soil interaction was divided into soil cutting and screw conveyance processes, ignoring the differences in soil mechanical properties between them. To improve the modeling accuracy, a hypothesis that divides the drill-soil interaction into four parts: cuttings screw conveyance, cuttings extruding, cuttings bulldozing, and in situ simulant cutting, is proposed to establish a novel model based on the passive earth pressure theory. An iterative numerical calculation method is developed to predict the drilling loads. A drilling and coring testbed is developed to conduct experimental tests. Drilling experiments indicate that the drilling loads calculated by the proposed model match well the experimental results. The proposed research provides the instructions to adopt a suitable drilling strategy to match the rotary and penetrating motions, to increase the safety and reliability of drilling control in lunar sampling missions.

A critical review of modelling methods for flexible and rigid link manipulators

“…The large deflection and post-failure issues cannot be handled by the FEM. Moreover, the FEM may suffer from mesh distortion and results in an inaccurate solution [46].…”

Laboratory construction and curation scheme for returned samples of the chang’e-5 mission

“…For investigations on Earth, a single Earth sample should be large enough to acquire an averaged representative composition through grinding processes without any other interference. Nevertheless, due to the scarcity of lunar samples, only a small quantity of pieces or repeatable usable slices, even lunar regolith simulant, such as CUMT-1 (McKay et al 1994;Quan et al 2018;Li et al 2022), are permitted to be investigated. If the demands for such investigations cannot be fulfilled, petitioners can submit an application with detailed descriptions of special scientific demands, and a slightly larger slice of samples could be prepared for the investigator after acceptance by scientific peer review (Zeigler et al 2007;Zhang et al 2020).…”

Drilling study of bit in gravel environment based on DEM–MBD

“…Isaka et al 10 studied the rake-type earth auger and the cone-tip-type earth auger, and found that the cone-tip-type earth auger can reduce the conveying torque better than the rake-type earth auger. Quan et al 11 proposed an iterative numerical calculation method for predicting drilling loads based on drilling experiments.…”