【摘要】：本文在分析國內(nèi)外機床誤差控制及誤差建模研究現(xiàn)狀的基礎(chǔ)上,系統(tǒng)研究了運動條件下的機床誤差建模與分析方法,并建立了機床的通用誤差模型。依托該模型對機床誤差進行動態(tài)分析,包括誤差的動態(tài)敏感度分析和作用規(guī)律分析;在分析的基礎(chǔ)上,提出了面向加工精度的機床誤差控制方法,開發(fā)了機床誤差分析與控制的軟件模塊。本文主要研究內(nèi)容如下:第一章介紹了進行課題研究的主要背景,以及國內(nèi)外研究學(xué)者關(guān)于機床誤差控制及誤差建模兩個方面的研究情況,系統(tǒng)地分析了現(xiàn)階段研究存在的不足,闡明了本課題研究的意義及主要內(nèi)容。第二章簡要介紹了數(shù)字化機床誤差建模所需的基本理論與方法,闡釋了建模所依賴的基本理論“多體系統(tǒng)理論”及“齊次坐標(biāo)變換理論”,歸納了機床通用誤差模型的建立方法;提出了機床運動條件下誤差敏感性分析的步驟及方法。以某目標(biāo)機床為例,完成了z軸、x軸運動條件下組成該機床9個部件間的54項單元誤差的誤差敏感度分析。結(jié)果表明,在運動條件下,部分單元誤差的敏感度發(fā)生變化,體現(xiàn)在敏感度的數(shù)值變化和敏感方向變化兩個方面,該分析結(jié)果為機床誤差的動態(tài)定量控制提供依據(jù)。第三章以機床運動誤差模型為基礎(chǔ),給出了運動條件下機床誤差作用規(guī)律分析的方法及一般步驟。機床誤差作用規(guī)律的分析包含單個誤差單元作用規(guī)律分析和多個誤差單元作用規(guī)律分析兩部分。前者是在運動條件下,分析區(qū)間內(nèi)的單個誤差單元所引起的機床x、y、z三個方向上綜合誤差的變化規(guī)律;而通過多個單元誤差作用規(guī)律分析,可以掌握各誤差源在傳遞過程中相互疊加或抵消的規(guī)律。第四章以控制工件加工誤差為目的,提出了機床誤差控制的方案。以車床上加工典型表面—圓柱面和端面為對象,分別對理想條件和誤差存在條件下的工件表面加工進行可視化仿真,并通過編程,實現(xiàn)其圓柱度和平面度的數(shù)字化評定。根據(jù)模型需要,確定了基本公差項目的約束條件,用部件公差對機床整體誤差模型中的參數(shù)進行約束。與機床誤差的基本模型結(jié)合,探討了公差約束下的工件加工精度控制方法。計算了部件公差約束下六自由度誤差的變化范圍,在假定這些誤差服從均勻分布的條件下,輸入模型獲得了機床x、y、z三個方向上輸出誤差的統(tǒng)計規(guī)律。以工件x、y、z三個方向上的誤差變動量和圓柱面工件徑向全跳動為目標(biāo),根據(jù)誤差敏感性分析和公差作用規(guī)律分析,反求出符合條件的部件間的公差。第五章借助MATLAB GUI平臺,完成了“機床運動誤差建模模塊”、“誤差敏感性分析模塊”和“工件數(shù)字化成形模塊”的編制。第六章總結(jié)了全文的工作;對機床誤差控制和誤差建模的后續(xù)研究進行展望。
[Abstract]:On the basis of analyzing the research status of machine tool error control and error modeling at home and abroad, this paper systematically studies the method of machine tool error modeling and analysis under moving conditions, and establishes the general error model of machine tool. Based on the model, the dynamic analysis of machine tool error is carried out, including the dynamic sensitivity analysis and action law analysis of the error, and based on the analysis, the error control method of machine tool oriented to machining accuracy is put forward. A software module for error analysis and control of machine tools is developed. The main contents of this paper are as follows: the first chapter introduces the main background of the research, and the domestic and foreign scholars' research on error control and error modeling of machine tools. The deficiency of the present research is systematically analyzed, and the significance and main contents of this research are expounded. In the second chapter, the basic theories and methods for error modeling of digital machine tools are briefly introduced, and the basic theory of multi-body system theory and homogeneous coordinate transformation theory, which the modeling depends on, is explained. The method of establishing the general error model of machine tool is summarized, and the steps and methods of error sensitivity analysis under the condition of machine tool motion are put forward. Taking a target machine tool as an example, the error sensitivity analysis of 54 unit errors between 9 parts of the machine tool is completed under the condition of z axis x axis motion. The results show that the sensitivity of some unit errors changes in two aspects: the numerical change of sensitivity and the change of sensitivity direction. The results provide the basis for the dynamic quantitative control of machine tool errors. In chapter 3, based on the kinematic error model of machine tool, the method and general steps of analyzing the law of machine tool error under moving condition are given. The analysis of machine tool error action law includes two parts: single error unit action law analysis and multiple error unit action law analysis. The former is to analyze the variation law of synthetic error in three directions of machine tool xyz. caused by a single error unit in the interval under the condition of motion, but through the analysis of the law of action of multiple unit errors, The law of superposition or cancellation of each error source in the transmission process can be grasped. In chapter 4, the scheme of machine tool error control is put forward to control the machining error of workpiece. Taking the typical workpiece surface and the end surface of lathe as the object, the machining of workpiece surface under ideal condition and error condition is simulated, and through programming, the digitized evaluation of cylindrical degree and flatness is realized. According to the requirements of the model, the constraint conditions of the basic tolerance items are determined, and the parameters of the overall error model of the machine tool are constrained by the component tolerance. Combined with the basic model of machine tool error, the control method of workpiece machining precision under tolerance constraint is discussed. The variation range of six degrees of freedom errors under component tolerance constraints is calculated. Under the assumption that these errors are uniformly distributed, the statistical law of output errors in three directions of machine tool xyyz is obtained by the input model. Aiming at the error variation in the three directions of the workpiece xyyniz and the radial full runout of the cylindrical workpiece, the tolerance between the parts that accord with the conditions is obtained according to the error sensitivity analysis and the tolerance law analysis. In the fifth chapter, with the help of MATLAB GUI platform, the modules of "modeling of machine tool motion error", "error sensitivity analysis module" and "digitized forming module of workpiece" are completed. Chapter 6 summarizes the work of this paper, and looks forward to the following research on machine tool error control and error modeling.
【學(xué)位授予單位】：重慶理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TG502

【參考文獻】

相關(guān)期刊論文 前1條

1 盛伯浩;數(shù)控機床的現(xiàn)狀與發(fā)展[J];制造技術(shù)與機床;2004年01期

，

本文編號：2167961