一种多功能小行星采样器的设计

Design of a Multi-function Minor Planet Soil Sampler

对距离地球较远的小行星表面进行松散土壤和岩石的采样任务时,需要采集不同深度的土壤样品并就地进行分析,并将有价值的数据传回地球。为此研究一种多功能采样器,进行钻进机构、取样机构和密封加热机构等关键组成部分的设计,能实现土壤和岩石样品的采样、体积测量和加热任务。由于钻进过程中,钻杆的约束条件发生变化,为分析钻杆的稳定性,建立动态压杆稳定模型,计算钻杆稳定的临界载荷;考虑钻孔深度变化、钻杆导向约束等不断变化的条件,分析钻杆振动频率的变化规律,利用ANSYS软件仿真,得到了钻杆随钻进深度变化的一阶固有频率区间。对耦合的密封力和加热开关接触力进行计算,得到了满足要求的可靠驱动扭矩。通过原理样机的制作与试验,验证了多功能采样器的设计合理性,达到了质量轻、功耗小、功能多、采样量大的效果。

The soil and rock sampling mission of planetoids far from the earth is a special topic.The soil samples in different depths should be analyzed in place and the data should be transmitted back to us.A multi-function sampler is presented to fulfill the requirements with carefully design,including the design of the drilling system,the sampling system and the heating system,and the soil and rock sampling,volume measuring and heating functions.The constraints of the drill string are changing during the drilling process,so a dynamic buckling model for the drill string is established.The frequency of the drill string is discussed as it is also affected by the changing constraints.By using the ANSYS model,the frequency band is obtained.The coupled sealing force and switch contact force are calculated to determine the reliable driving torque of the actuator.A prototype is established and the functions of the sampler are verified.The sampler is demonstrated as a light weight,low power consumption,multiple functions and large sampling capacity system.