Drill Thermal Characteristics Test System Development And Experiment Research Of The Lunar Surface Drilling Sampling Process

The main task of Chinese Lunar Exploration project (third section) is toachieve lunar samples returned to Earth, as the lunar surface environment is highvacuum and low thermal conductivity of lunar regolith, and drill in the drillsampling process used is dry drilling mode without using water and other coolingmeasures, the drill in the drilling process will generate a lot of heat and heat buildupresulting drill temperature rising, high temperature will course drill occurs failureand lead to drill task failure. Therefore, based on a certain configuration of samplingtool, this article carried out experimental study the thermal characteristics of drilldrilling process.Analyzed the structure of varus soft bags coring drill and works, from twoaspects of sampling object properties of drilling tools and work environment,analyzes the factors affecting thermal characteristics of sampling drill drillingprocess. For prediction of extreme working condition of drilling simulant lunarrocks, through the estimated parameters such as heat flux, conducted a steady-statethermal analysis based on ANSYS, won the drill temperature distribution, andpredicts the range of temperature measurement system.According to the prediction of temperature measurement system range,developed temperature online measuring system based on fiber optical fiber gratingsensor and wireless type K thermocouple sensor，the system has a larger range, goodmeasuring precision and dynamic responsive characteristics, and integrate the testsystem in sampling drill test platform developed by satellite factory in Beijing andfull monitoring sampling drill test platform developed by Harbin Institute ofTechnology, respectively.Carried out the drill thermal characteristics test and research of drillingsampling process based on the simulant moon rocks and soil. In the thermalcharacteristics of simulated lunar drilling test research, carried out research oftemperature drill drilling laws based on vacuum environmental conditions, loadobjects, dynamic parameters of drilling and research on temperature distributionbased on drill multi-point temperature monitoring. In the study of simulant regolithtest, carried out research on temperature rising law of drill drilling process at roomtemperature based on all drilling dynamic parameters, designed the drilling processthermal characteristic comparison tests, which between simulated lunar surface lowtemperature environment and normal temperature and pressure. After obtained thedifferences law between low temperature and under normal temperature conditionsof drill drilling temperature rise, obtained the thermal characteristics laws of drill drilling process at lunar surface low temperature environment and predicted thesafety drilling dynamic parameters on drilling lunar soil.This paper obtained the risks of drilling thermal characteristics and therelationship between drill drilling procedure parameters and drill heating, which willfor the subsequent deepening of drill materials, configuration design, and drillingdrill sampling strategies provide the basis for determining.