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Martian rocks contain crucial information about the genesis of Mars and the historical evolution of Martian climate change. Consequently, extracting and examining Martian rocks are pivotal in advancing our comprehensive understanding of the red planet. However, the current core drill string is prone to wear and tear, and the samples are susceptible to thermal denaturation. To address these challenges, we introduce two novel types of drill bits, the conical straight junk slot and the conical spiral junk slot, both employing impregnated diamond as the primary material. Comparative experiments were meticulously conducted to evaluate the influence of different junk configurations on drilling parameters, including speed, abrasion resistance, drilling force loading, and sample temperature rise. The findings unequivocally demonstrate the superior performance of the spiral junk slot. Furthermore, simulations were performed to examine the drilling process on basalt using a fixed configuration drill bit, validating the occurrence of the sample temperature rise. The research presented in this paper offers valuable programmatic references and essential data support for future Martian rock coring drilling missions. [ABSTRACT FROM AUTHOR]

The nitrogen isotopic compositions of lunar soil have important implications for the sources of lunar volatiles and even the evolution of the moon. At present, the research on the lunar nitrogen isotopic compositions is mainly based on the lunar meteorites and the samples brought back by the Apollo and Luna missions. However, volatiles adsorbed on the surface of the lunar soil may be lost due to changes in temperature and pressure, as well as vibration and shock effects when the sample is returned. At the same time, in the case of low N content in the sample, since N is the main component of the earth's atmosphere, it is easily affected by the atmosphere during the analysis process. Therefore, in situ nitrogen isotopic analysis of lunar soil on orbit is necessary to avoid the problems mentioned above and is one of the primary science goals for the Lunar Soil Volatile Measuring instrument on Chang'e-7 spacecraft. After the nitrogen purification procedure, the volatiles in lunar soil that are released through single-step or stepped heating techniques diffuse to the quadrupole mass spectrometer to obtain the N contents and isotopic compositions of the lunar soil. This paper introduces the ground test for N isotopic analysis of lunar soil in orbit according to the Lunar Soil Volatile Measuring Instrument. After long-term repeated measurements, the background and CO-corrected Air-STD 14N/15N ratio is 268.986 ± 4.310 (1SD, n = 35), and the overall reproducibility of measurements is 1.6%. The accuracy of N isotopic compositions is calculated to be better than 5%, which can distinguish different sources of N components in lunar soil. [ABSTRACT FROM AUTHOR]

According to the big impact hypothesis, the moon should be very dry. However, more and more evidence from the remote sensing of the moon in recent years indicates that there is a lot of water in the moon's polar regions. Researching the source and distribution of volatiles such as water can provide a key constraint on the formation and evolution of the moon. If there is a large amount of a volatile such as water ice in the polar area of the moon, it can be used as a further resource. Regrettably, there are no detectors in place to detect the amount and presence of water to date. In the new wave of lunar exploration, polar water has become one of the main tasks of NASA, ESA and RKA. The Chang'e-7 spacecraft of China's fourth lunar exploration phase has also used the Water Molecular Analyzer and the Lunar Soil Volatile Measuring Instrument to detect water content in the lunar polar region. This paper introduces a set of methods and principles for analyzing water content via the heat flux method according to the characteristics of the Lunar Soil Volatile Measuring Instrument that was deployed on the lunar surface. According to the current design, the water content of 0.008~0.17% can be analyzed. [ABSTRACT FROM AUTHOR]

To provide reliable input information for the load design and extraction of lunar soil water ice samples, it is necessary to study the water content distribution and water migration of simulated lunar soil water ice samples. On this basis, the temperature field model and the hydrothermal coupling relationship are proposed. The temperature field model was constructed by combining energy conservation and Fourier's heat transfer law. The coupling relationship was established, and the hydrothermal coupling model was obtained by testing the unfrozen water content using the nuclear magnetic resonance method. Finite element software was used to solve the model numerically, and the water migration rule of the soil water ice samples at different ambient temperatures were analyzed. Thin-wall drilling tests were carried out on the simulated lunar soil water ice samples to obtain water content data for different locations, and the simulation results were verified. Due to the migration effect of the cold end of the water, the closer we tested to the edge of the sample, the higher the water content was. The higher the ambient temperature was, the more pronounced the water migration phenomenon of the whole sample was. These research results provide a basis for sampling scheme design. [ABSTRACT FROM AUTHOR]

During drilling into the soil, the rotating mechanical structure will be affected by soil particles and external disturbances, affecting the health of the rotating mechanical structure. Therefore, real-time monitoring of the operational status of rotating mechanical structures is of great significance. This paper proposes a working state recognition method based on Mel-spectrum and transfer learning, which uses the mechanical vibration signal's time domain and frequency domain information to identify the mechanical structure's working state. Firstly, we cut the signal at window length, and then the Mel-spectrum of the truncated signal is obtained through the Fourier transform and Mel-scale filter bank. Finally, we adopted the method of transfer learning. The pre-trained model VGG16 is adjusted to extract and classify the features of the Mel-spectrum. Experimental results show that the framework maintains an accuracy of more than 90% for vibration signals under minor window conditions, which verifies the real-time reliability of the method. [ABSTRACT FROM AUTHOR]

A new screw conveyor with flexible discrete spiral blades is proposed to solve the problem of particle material gathering between the screw and the tube wall in the traditional screw conveyor. With a theoretical analysis, the power consumption model of the screw conveyor with flexible discrete spiral blades is built. Then, its practicability is verified by simulation and experimental testing. The simulation results show that the increase of the spiral angle will raise the transportation speed of the particles. The diameter of the flexible blades raises with the increase of the power consumption of the screw conveyor. The experimental testing verified the analysis and simulation results. [ABSTRACT FROM AUTHOR]