基于单刃切削模型的钻具与月壤相互作用特性研究

发布时间：2018-06-20 04:07

本文选题：月壤 + 钻取采样　；参考：《哈尔滨工业大学》2014年硕士论文

【摘要】：我国探月工程三期的目标是完成月面采样任务并返回地球。钻具与月壤相互作用特性包含钻进取芯时钻具与月壤间的力学特性和钻具的排粉特性。在月面钻取采样任务中，钻具与月壤相互作用的力学特性及钻具的排粉特性是钻取采样装置研制、钻具构型参数优化及钻进规程研究的基本依据之一。依据经典土力学中的极限平衡理论分析采样钻具对模拟月壤钻进取芯过程中钻具与月壤相互作用的力学模型。研究采样钻具取芯过程中钻具的排粉特性，并采用图像处理的方法实时监测钻具的排粉特性。面向钻取采样装置低功耗、高可靠性、高取芯率的设计要求，提出了“空心外螺旋钻杆+V型刃钻头”组合形式的取心钻具。空心外螺旋钻杆具有较好的排粉特性，是地外天体钻取采样探测任务中常用的一种钻杆形式。V型刃钻头的钻头体上镶嵌有四个V型切削刃，能够更好地侵入硬质月壤，并取得较高的取心率。钻进取芯过程中Ｖ型刃钻头的四个切削刃同时对模拟月壤进行切削，四个切削刃间相互影响，产生的切削阻力相互耦合在一起，难以准确建立钻头的切削阻力模型，因此需要简化钻头的切削阻力模型。将钻头切削模拟月壤时V型切削刃的回转运动简化为切削刃的直线切削运动。依据经典土力学极限平衡理论建立单个V型切削刃直线切削模拟月壤时的单刃切削模型，，并对该模型开展试验验证。考虑V型切削刃直线切削与回转切削的不同点，基于V型切削刃的单刃切削模型建立钻头对模拟月壤的回转切削力学模型。参照单刃切削模型中模拟月壤的失效模型，分析采样钻杆螺旋排屑槽内钻屑月壤的运动形式和受力情况，建立钻具排粉过程中的排粉阻力矩模型。采样钻具在钻进取心过程中，钻具与月壤相互作用的力载特性和钻具的排粉特性是一个相互耦合不可分割的整体，需要研究钻具的排粉特性。分析采样钻具钻进取心过程中产生的钻屑月壤的位置流向，建立不同位置流向的钻屑月壤与钻孔内原位月壤间的体积对应关系模型，以分析的钻具排粉特性。提出基于图像处理的堆积区月壤体积特性非接触式测量方法，实时监测采样钻具的排粉特性，并将测量结果作为变量参数引入到钻杆的排粉阻力矩模型和钻具的排粉模型中，分析钻具与月壤相互作用特性。
[Abstract]:The goal of the third phase of China's lunar exploration project is to complete the lunar surface sampling mission and return to Earth. The interaction between drilling tool and lunar soil includes the mechanical properties of drilling tool and lunar soil and the characteristics of drilling tool powder removal. In the lunar drilling sampling task, the mechanical characteristics of the interaction between drilling tool and lunar soil and the discharging characteristics of drilling tool are one of the basic basis for the development of drilling sampling device, the optimization of drilling tool configuration parameters and the study of drilling rules. Based on the limit equilibrium theory in classical soil mechanics, the mechanical model of the interaction between the drilling tool and the lunar soil during the drilling and coring simulation of lunar soil is analyzed. In this paper, the powder removal characteristics of drilling tools in the process of coring are studied, and the image processing method is used to monitor the characteristics of drilling tools in real time. In order to meet the design requirements of low power consumption, high reliability and high coring rate of drilling sampling device, a "V-shaped drill bit with hollow outer spiral drill pipe" is proposed. The hollow outer spiral drill pipe is a common type of drill pipe in the field of sampling and detecting by the ground object. The drill body of the V-shaped drill bit is embedded with four V-shaped cutting edges, which can better invade the hard lunar soil. A higher heart rate was obtained. In the process of core-drilling, the four cutting edges of V-shaped bit are simultaneously cutting the simulated lunar soil. The cutting resistance produced by the four cutting edges is coupled with each other, so it is difficult to establish the cutting resistance model of the bit accurately. Therefore, it is necessary to simplify the cutting resistance model of bit. The rotary motion of V-shaped cutting edge is simplified as the straight cutting motion of cutting edge when bit cutting simulates lunar soil. Based on the limit equilibrium theory of classical soil mechanics, a single-edge cutting model for simulating lunar soil with a single V-shaped cutting edge was established, and the model was tested and verified. Considering the difference between straight cutting and rotary cutting of V-shaped cutting edge, the rotary cutting force model of bit to simulate lunar soil is established based on the single-edge cutting model of V-shaped cutting edge. According to the failure model of simulating lunar soil in single-edge cutting model, the movement and force of lunar soil in the spiral chiphole of sampling drill pipe are analyzed, and the model of draining resistance moment of drilling tool is established. In the process of drilling for coring, the interaction between drilling tool and lunar soil and the characteristics of drilling tool discharging powder are an inseparable whole, so it is necessary to study the characteristics of drilling tool powder removal. This paper analyzes the position and direction of lunar soil produced by drilling with sampling drilling tool, and establishes the volume correspondence model between drilling cuttings lunar soil and in-situ lunar soil in drilling hole, so as to analyze the characteristics of drilling tool powder discharge. A non-contact measurement method based on image processing for the volume characteristics of lunar soil in the accumulation area is proposed to monitor the dust discharge characteristics of the drilling tools in real time, and the measured results are introduced as variable parameters into the draining resistance moment model of the drill pipe and the powder discharge model of the drilling tool. The interaction between drilling tool and lunar soil was analyzed.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P634;P184.5

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