Study On Self-balancing Sampler Sampling Of Lunar Soil With Water Ice

At present,lunar soil sampling is mainly divided into two ways: penetration sampling and rotary sampling.Rotary sampling in the face of different lunar soil environment which has a lot of its own difficult to solve the problem.When the rotary sampling of loose lunar soil acquisition,due to the need for rotary motion to collect samples,it is usually difficult to retain the original information of the lunar soil layer.Therefore,people can not estimate the true geological structure of the moon in scientific research.In addition,when rotary sampling is used to collect hard rock lunar soil containing water-ice mixture,due to insufficient rotary impact force,the interaction force between lunar soil particles cannot be broken,so the sampling purpose cannot be achieved.However,these problems can be solved by adopting penetration sampling.By studying the existing lunar soil sampling device at home and abroad as well as basing on the characteristics of single direction displacement mechanism of micro particles,a novel impact penetration sampling device with double vibration body was proposed.It has the advantages of no rotation motion,simple structure and direct transmission.Combined with the physical characteristics of the lunar soil layer,the traditional penetration sampling device was optimized and innovated.Based on the traditional particle migration mechanism,the double penetration sampling process was analyzed.Three driving schemes were designed and the final driving scheme was confirmed by analyzing the advantages and disadvantages of different schemes.The finite element simulation of the device was carried out by electromagnetic simulation software,and obtained the magnitude of the vibration penetration force under different input currents alone.Aiming at the complexity of lunar soil composition and the diversity of sampling objectives,according to the selected driving scheme,the remaining parts of the sampler were dsigned and the static strain simulation analysis of the roadheader which needs to be subjected to mechanical impact was carried out which verified the reliability of the penetration machine.The principle prototype was processed and the test platform was built.In the experimental verification of the sampler,the modal analysis equipments were used to analyze the modal of the sampler,and the natural frequency of the sampler was obtained.According to the physical properties of lunar soil and the selection materials of particle size,the lunar soil was simulated and prepared under different conditions.The effects of different current on the sampling rate and penetration rate of two kinds of lunar soil were obtained by simulation sampling test and tunneling test.For the samples taken,the lofting test was carried out to obtain the relationship between the lofting speed and the input excitation.The working objective of the sampler was to detect whether there is a mixture of water and ice in the lunar soil,and the variation curve of the surface temperature of the penetration machine was obtained through long-term penetration.The initial research of the double body vibration and penetration lunar soil water ice sampler is completed by the way of principle description,scheme analysis,structure design,simulation optimization and test verification.A new sampling structure is proposed and the influence of relevant parameters on the device is studied,which provides a new basis for further optimization of the structure parameters of the sampler,A new sampling device scheme is provided for the penetration sampling of lunar soil in China.