Multi-scheme analysis and optimization of Lunar soil drilling load mechanism driving unit interface

One of the main tasks of China´s Phase III Lunar Exploration Project is to acquire lunar soil sample more than two meters deep under lunar surface and bring it back to the earth. For an essential part of drilling and sampling device, functioned as the drilling pressure providing apparatus, reasonable scheme design of the load mechanism driving unit interface guarantees the reliability of the drilling and sampling mission. Based on intensive analysis of its required function and special requirement, this paper shows the working principle of load mechanism and proposes two structure schemes according to connection mode and guidance mode between drum and wire rope respectively. Mechanical model is established in each scheme so as to analyze the interaction between structure parameters and load performance. Relevant model parameters are determined in certain scheme. Analytic hierarchy process is introduced, along with appropriate defined evaluation indices, to establish an evaluation model for optimization of above four load mechanism driving unit interface schemes.