模拟火壤结壳及其力学性能试验

Experimental on mechanical properties of simulated Mars soil crust and its crusting

火星表面除松散火壤外,还有一类特别的火壤类型——硬壳类火星地面,该火壤表层为脆性,底层为松软沙粒,对巡视器移动具有迷惑性。研究以Mars-1和Mars-3模拟火壤为对象,通过喷洒蒸馏水、MgSO_(4)和NaCl溶液,自然风干形成硬质土壳结构。对所得土壳进行承压、贯入阻力和火星车通过性试验研究,结果表明:细颗粒Mars-1采用饱和NaCl溶液时结壳效果最好,面积最大且整体性强;粗颗粒的Mars-3采用10%MgSO_(4)溶液时结壳效果最好,面积较小,土壳厚度较厚但易碎。Mars-1结壳速度较Mars-3快。承压特性分析中,Mars-1土壳破坏点峰值载荷随NaCl浓度的提高而降低,随MgSO_(4)浓度的提高而升高。两种土样均采用10%NaCl溶液结壳时,贯入阻力最大。对于Mars-1,贯入阻力随NaCl浓度的增加而增加,随着MgSO_(4)浓度的增加而降低。所制备薄壳地形,满足火星车通过性试验需求。以上研究可为星球车行走机构优化设计和通过性能评估提供参考和依据。

Except the loose soil on the surface of Mars,there is a kind of special type of soil names Crustycloddy,where the ground surface is brittleness and the underlying is loose sand.That is deceptive for Mars Rover.This article take theMars-1and Mars-3 simulant Mars soil as the raw material,to formed hardshell structures under the nature dry,then studied on the mechanics of these crust,the results showed that the crust of fine particles Mars-1 soil is best when the liquor is saturated NaCl,which has the biggest area,strongly integrity and small thickness;while the Mars-3 crusted the best when liquor is 10%MgSO_(4),which has a small area,large thickness but weak integrity.The crusting velocity of Mars-1 is faster than that of Mars-3.Concerning about loading properties,the peak broken force for crust of Mars-1 decreased with the increasing of the concentration of NaCl but increased with the increasing of the concentration of MgSO_(4).Two kinds of crust have the biggest penetration resistance under the liquor of 10%NaCl.For Mars-1,the penetration resistance increases with the increasing of the concentration of NaCl but decreases with the increasing of the concentration of MgSO_(4).The above research can provide the reference and basis for the planet ramp mechanism optimization design and performance evaluation.