Development And Simulation Of The Moon Sample Drilling Platform

In the context of the unmanned sample drilling on the moon surface,which is part of the work included in Phase 3,Stage 1 of the Chinese Moon Exploration Project,this paper is aimed at solving the sample drilling difficulties that traditional approaches cannot cope with due to the complicated environment of the moon surface. A conceptual drilling process applicable to the moon surface operating condition is proposed through review of foreign experience on the moon surface sample drilling and the present research situation of China.Two alternatives for the mechanical top drive head were presented through analysis of the environment of the moon surface,theoretical calculation of the drilling parameters based on the physical properties of the moon soil, and taking into account of the overall design requirement on the drilling core device.The basic structure of the top drive head for this research was determined by analyzing the benefits, and the feasibility of each alternative.Then, the detailed design of the top drive head was done as per the follow-up testing requirements.The hollow outer spiral drill pipe was selected as the basic structure of supporting drilling tools according to the drilling process.Also, a series of single and double helix drill pipes with various screw pitches were designed. The design and model selection for the test system and test bench was conducted according to the functional requirements on the test platform to meet the functional requirement for different drilling tests.The entire test platform was designed, produced, assembled and commissioned.The test platform was tested to check if it met the design requirement.Then, the mechanical properties of the top drive head,the specification of supporting drilling tools, and the relevant drilling parameters were tested. By analyzing the effect of single and double helix drill pipes on the drilling efficiency under the same condition,the type of spiral drilling tools suitable for the driller were selected. The simulating drilling test was conducted at different WOB, RPM and impacting frequency. Then, the range of the optimal WOB, RPM and impacting frequency suitable for the designed drill was determined. Finally, the structure of the top drive head was redesigned according to the theoretical and practical results, and the material of the drill was selected to meet the requirement for compactness, portability,high efficiency and low power consumption.