Research On Micro-quantitative Sampling Technology With Sieving Constant Volume For Profile Of Lunar Soil

Because of its great scientific research value,the geological exploration of the lunar polar region is becoming a hot spot in the deep space exploration competition.my country will also carry out the in situ comprehensive detection of the lunar south pole sunshine area with the scientific payload carried by Chang'e 7,and conduct pyrolysis mass spectrometry detection of the lunar soil volatile matter and its isotopic content.This will be the first in situ determination of the surface age of the lunar landing area in the world,and will be the first to realize the measurement of volatile distribution in the lunar polar region.For the measurement method of pyrolysis mass spectrometry,it is required that the sample to be measured should be collected at multiple points in a wide area from the lunar surface to the 300 mm depth profile.Since more than 90%of the volatile matter is adsorbed on the surface of the lunar soil,the target lunar soil particle size is required to be fine soil with a larger specific surface area less than 1 mm,and the high precision of the pyrolysis mass spectrometer determines that the total amount of a single sample does not exceed 100 mg.According to the error analysis of lunar soil dating method,the sampling accuracy error of the measured samples should be controlled within±6.25%.The lunar soil is obviously angular in shape,and the particles are easily interlocked.The lunar soil in the polar region is about 40%larger than the equatorial lunar soil in particle size.Due to the low gravity of the moon and the low incidence angle of the polar region,the Sampling equipment must have low power consumption and low load.Therefore,this paper will carry out the research on the quantitative trace sampling method under multiple working conditions based on the target requirements of the Chang'e 7 scientific payload.The main work is as follows:Define the target object of micro quantitative sampling according to the target requirements.The overall scheme design is carried out for the sampling target object,the physical and mechanical properties of lunar soil are studied,and the influence of lunar soil characteristics on sampling is analyzed.The profile drilling test is carried out according to the actual technical state.Profile drilling into the lunar soil and the lunar soil in the debris storage area to analyze the particle size,in order to evaluate the preparation principle of the lunar soil drilling and the particle size replacement process of the lunar soil in the debris storage area in the drilling chip removal.The sample characteristics are used as the basis for the formulation of multiple working conditions of the sampling test.Decompose the functional and performance requirements of the sampling system according to the sampling requirements.According to this,it is required to clarify the design input of the a Sampling piece iterate the plan of the Sampling piece with different sampling principles and conduct sampling tests on them.The test results were evaluated based on the sampling amount of simulated lunar soil samples,sampling accuracy,whether the samples were saturated and filled,and whether they could be heated by electromagnetic induction.The functional requirements of the temporary storage cup are clarified,the principle scheme of the temporary storage cup is designed,and the test pieces are processed and manufactured,so as to provide the configuration basis for the optimization of the Sampling piece.Analyze the quantitative sampling principle and sampling process of the Sampling piece.The design goal of the injection hole of the Sampling piece was decomposed,and the sampling principles of the injection holes of different configurations of the Sampling piece were analyzed.Carry out sampling tests of Sampling piece with different configurations of injection holes.The test results were evaluated with sampling quantity and sampling efficiency as evaluation indicators.Clarify the design goals of the exclude sample fins,analyze the force of the exclude sample fins under different torsion angles.Combined with the configuration of the injection hole and the exclude sample fins and the restrictions on the configuration of the Sampling piece by the system,the overall configuration of the Sampling piece is preferred.This provides a entity structure of the Sampling piece for the sampling test.Design a micro-quantitative sampling test plan and plan the sampling test process,so as to build a micro-quantitative sampling performance test platform,According to the characteristics of the sample in the chip storage area,three lunar soil conditions for micro-quantitative sampling were formulated and prepared.The particle size distribution of the three lunar soil conditions was analyzed by laser particle size analysis to evaluate the matching of the conditions.Based on the test platform and different lunar soil conditions,the micro-quantitative sampling characteristic test was carried out to obtain the force load during the sampling process and analyze the characteristics of the collected samples,so as to verify the sampling performance of the micro-quantitative sampling method.