The Dynamic Analysis And Experimental Research Of Lunar Sample Drilling Device

In Lunar drilling sampler, the motion of slender drill pipe includes rotation, axis shock and feed. Three mechanics models and dynamic equations were established in the thesis, which were dynamic equation of rotation system of drilling device with driving motor, gear transmission, and drilling pipe; dynamic equation of drilling pipe with coupling of axis pushing shock and torsion; and mechanics model and dynamic equation of feeding system of drilling device with driving motor and cylinder, winding cylinder and wire rope pulling drilling device, drilling device pushing drilling pipe feeding. The Runge-Kutta method and MatLab software were used for the numerical solutions of the dynamic equations, the analysis of the responds and the nonlinear characteristics of drill pipe under different complex dynamic loads, and the research of the dynamic characteristics of system and effectiveness of main parameters to the performance of drilling. The nonlinear bending vibration equation was established for the simply supported slender drill pipe under axis pressing force and light gravity of moon at a certain inclination angle with drill pipe. The progressive solution of main resonance vibration was got by using multi-scale perturbation method. The analysis was done for the responds of amplitude to frequency, stability of motion, variation of amplitude and the experiment of responds of amplitude to frequency. The nonlinear equation of complicated vibration model was also established for the slender drill pipe which one part was simply supported and other part was overhanging. The analysis was done for the vibration and stability of the slender drill pipe. The research results provided the theoretical foundations for the parameters design of the sampling and the stability and reliability of the drill pipe during the working process. The prototype of lunar soil drilling sampler was developed and the experiments and tests were done in the laboratory to simulate lunar soil drilling and sampling automatically. Finally, the success was achieved in key technology such as getting core soil, impact-rotary drilling, sample spiral shaping and recycling, which was the fundamental work for China lunar exploration sampling and future deep space exploration sampling technology.