The Cross-section Simulant Of Lunar Regolith And Research On Drilling Load Feature

The main task of China's Lunar Exploration Project Phase ?(Chang'e 5 detector)is to achieve lunar samples and send back to the earth.The automatic collection of the lunar samples and exploration in the original location is one of the most important methods to deepen the understanding about lunar science.On macro-scale,the lunar soil is composed of rocks,mineral detritus,glass particles,breccias and agglutinating rocks,it is the material accumulated by natural particles matters which develops under the comprehensive actions of meteorite impact,cosmic radiation,striking of solar wind particles,huge diurnal temperature difference without air and water.There are obvious differences between the lunar soil and earth soil on chemical composition,particle morphology,size distribution,relative compaction and comprehensive soil mechanical parameters.Under the engineering background of lunar drilling and coring task,this paper carried out a research work systematically,targeting at simulating the lunar profile sample and figuring out the scope of drilling load.Through investigating the scientific analysis data of lunar samples achieved by American Apollo Project and Russian Luna Project,the control quota of simulated lunar soil materials and particle morphology are obtained,meanwhile,the equivalence between simulated lunar soil and the real lunar soil on soil mechanical parameters is realized which provide the technical basis to the preparation of the raw material of simulated lunar soil.The design basis and control methods of size grading,particles hardness and the relative compaction of lunar soil profile are obtained targeting at the coverage property of the drilling load in lunar soil profile.Through completing the design work on the simulated profile of lunar soil,the design criterion of three kinds of simulated profile of lunar soil including small-scale,critical-scale and large-scale soil is put forward.The devices used on the raw material mixing,size grading and relative compaction preparation are developed in this paper.The simulated lunar soil samples used to satisfy the need of earth verify tests of drilling and coring load is developed,which is equipped with the equivalence in mechanical parameters and the coverage property in severity.After scientifically designing the matrix of the drilling load tests,quantities of tests are carried out and the drilling and coring load scopes are obtained which provide the direct basis to the design of the drive part of the lunar drilling and coring devices and the parameters optimization of drilling rules.Comparing with lunar drilling and coring devices of the American Apollo Project and the Russian Luna Project,the design criterion on the equivalence and coverage properties of the simulated lunar soil profile obtained by this paper is a scientific method and possesses the practicability in engineering.The preparation techniques,preparation facilities and the obtained methods of the drilling load scope developed in this paper are applied roundly to the drilling subsystem of China's Lunar Exploration Project Phase ?.