仿真系统中的通用NC代码处理

一、前言在实际加工生产中，参与数控加工的主体是数控机床，而数控机床主要由四个主要部分构成，如图1所示。图 1 数控机床的组成其中伺服机构和机床本体是数控机床的硬件基础，决定了该类型的数控机床的功能。而数控装置作为数控机床的“指挥系统”，是数控机床最重要的组成部分。数控系统严格按照从外部输入的程序（NC代码）来指挥数控机床的硬件自动地对工件进行加工。在实际CNC加工生产中，由于机床的类型和生产厂家不同，其配备的CNC系统也是各不相同，因此虽然NC代码格式有国际标准，但各CNC系统的生产商各有一套标准，不同型…     

FANUC 0i数控系统常见P/S程序报警处理

在数控编程操作过程中,常因NC程序的编辑、输入、存储等环节有错误,导致数控系统不执行或中断执行NC程序。针对这个问题,本文通过使用FANUC 0i数控系统,以具体的数控加工实例,解读、分析在加工过程中经常出现的P/S程序报警代码信息,并作出相应正确处理,从而避免盲目查找报警故障信息原因的繁琐过程。     

FANUCOi数控系统常见P／S程序报警处理

在数控编程操作过程中,常因NC程序的编辑、输入、存储等环节有错误,导致数控系统不执行或中断执行NC程序。针对这个问题,本文通过使用FANUC0i数控系统,以具体的数控加工实例,解读、分析在加工过程中经常出现的P／S程序报警代码信息,并作出相应正确处理,从而避免盲目查找报警故障信息原因的繁琐过程。     

一种开放式数控系统刀具运动轨迹验证方法

为了更准确的仿真五轴数控机床各运动轴的运动情况,提出一种开放式数控系统刀具运动轨迹验证方法.本方法从运动控制组件中采集运动控制数据,利用五轴机床机构运动学模型,将运动控制数据转换为工件坐标系下刀具的运动轨迹,并以三维线框方式显示.通过CNC系统与CAD系统STL模型数据的交换,实现了刀具运动轨迹与CAD设计模型的分析比较,并设计了轨迹误差计算模型,可以定量分析仿真的刀具运动轨迹.最后通过实验验证了方法的正确性.     

数控车基于宏程序加工大螺距螺纹的仿真

Vericut软件是美国CGTECH公司开发的数控加工仿真系统,当前最新版Vericut 7.0可以仿真数控车床、铣床、加工中心、线切割机床和多轴机床等多种加工设备的数控加工过程,也能进行NC程序优化,缩短加工时间、延长刀具寿命、改善表面质量,检查过切、欠切,防止机床碰撞或超行程等错误。且具有真实的三维实体显示效果,可以对切削模型进行尺寸测量,并能保存切削模型供检验、后续工序切削加工。     

复杂零件数控加工的仿真与优化研究

复杂零件数控代码繁多,采用人工检测、试切和机床运行的代码检测方法将造成极大的资源浪费。为了减小这方面的浪费及提高复杂零件加工的质量,本文以减速器中的典型零件产品为例,在Vericut里面建立三轴加工环境及方针模型,对数控代码进行仿真。通过仿真,优化了数控代码,精确模拟出实际的加工过程,直观地观察到刀具的轨迹和工艺的可加工性,为复杂零件的高效数控加工提供了借鉴。     

数控专用加工代码O代码的功能实现

为了实现开放式机床控制数控系统NC代码解析运行的灵活性功能要求,提出了加工代码的控制流语句O代码的实现.通过对数控系统中的解析器模块进行分析,运用在linux平台下面的c 面向对象语言设计方法,本人将原有的解析器模块用类封装重新进行设计,对部分需要增强功能或是改变实现方式的子函数予以重新编写,提出了使用特有的数据结构封装代码状态数据,添加了统一的控制流语句、跳转功能,改良了代码解析的过程,提高了数控加工运行的灵活性.     

基于经济型控制系统（HNC-21T）的车床数控化改造

机床数控化已成为衡量一个国家机械制造工业水平的重要标志,世界上工业发达国家都把发展数控技术作为机械工业发展的战略重点。在比照分析目前国内在机床数控化改造中常用数控系统的特点、控制功能、价格后,研究了一种利用经济型数控系统对普通车床进行数控化改造的工程实践方法。在完成数控系统的选型、配置、参数设置及控制电路设计,机械部分（包括进给系统、主轴系统、刀架等）的改造设计之后,进行机电联调,测试改造后机床的功能和性能,并进行切削精度检验。     

数控龙门铣床数据采集系统综述

龙门铣床是机床族的重要机型,其应用广泛,尤其是数控龙门铣床在航空制造领域的地位举足轻重。数据采集系统是机床监控系统的前端子系统和关键组成部分,数据采集系统设计的成功与否,决定了机床监控系统的数据有效性。对应用于龙门铣床的数据采集系统进行研究,具较大的现实意义。在介绍数控龙门铣床的结构及功能的基础上,分析了数控龙门铣床的数据采集的核心需求,针对性地分析和总结了数据采集的手段和方法,并概述了数控龙门铣床数据采集系统的发展方向。为数控龙门铣床数据采集系统的设计提供了技术支撑。     

3V75立式加工中心

BV75是由北京机电院股份公司生产的立式加工中心，机床采用专业化厂家提供的数控系统，各直线运动轴、主轴及追加旋转轴均采用伺服电机驱动，三轴或四轴联动，可进行各种铣削、镗孔、钻铰孔、刚性攻丝等一般机械加工，并实现数字化精确定位，通过运动轴插补联动可实现旋切大螺纹、多种曲面加工，且同一台机床上可实现工件一次装夹过程中多种工序的粗、精加工。同时，数控系统中配备了多种典型循环程序供加工过程中编程选用。     

A novel approach to CNC machining center processing parameters optimization considering energy-saving and low-cost

NC machining is currently a machining method widely used in mechanical manufacturing systems. Reasonable selection of process parameters can significantly reduce the processing cost and energy consumption. In order to realize the energy-saving and low-cost of CNC machining, the cutting parameters are optimized from the aspects of energy-saving and low-cost, and a process parameter optimization method of CNC machining center that takes into account both energy-saving and low -cost is proposed. The energy flow characteristics of the machining center processing system are analyzed, considering the actual constraints of machine tool performance and tool life in the machining process, a multi-objective optimization model with milling speed, feed per tooth and spindle speed as optimization variables is established, and a weight coefficient is introduced to facilitate the solution to convert it into a single objective optimization model. In order to ensure the accuracy of the model solution, a combinatorial optimization algorithm based on particle swarm optimization and NSGA-II is proposed to solve the model. Finally, take plane milling as an example to verify the feasibility of this method. The experimental results show that the multi-objective optimization model is feasible and effective, and it can effectively help operators to balance the energy consumption and processing cost at the same time, so as to achieve the goal of energy conservation and low-cost. In addition, the combinatorial optimization algorithm is compared with the NSGA-II, the results show that the combinatorial optimization algorithm has better performance in solving speed and optimization accuracy.     

A novel methodology for cross-technology interoperability in CNC machining

In CNC part programmes, the lack of standardisation for representing part geometry and semantics of manufacturing operations leads to the necessity for existence of a unique part programme for each machine. Generating multiple programmes for producing the same part is not a value adding activity and is very time consuming. This wasteful activity can be eliminated if users are given the ability to write an NC program for a specific machine and robustly convert the program to syntax suitable for another CNC machine with a different structure. This, cross-technology interoperability, would enable for parts manufactured on old CNC machines using legacy code to be manufactured on new CNC machines by automatically converting the programmes. Every NC programme is written based on various categories of information such as: cutting tool specifications, process planning knowledge and machine tool information. This paper presents an approach for cross-technology interoperability by refining high-level process information (i.e., geometric features on the part and embedded manufacturing resource data) from NC programmes. These refined items of information stored in compliance with the ISO14649 (STEP-NC) standard may then be combined with new manufacturing resource information to generate NC code in a format that is compatible with machines based on different technologies. The authors provide a framework for this process of identification, semantic interpretation and re-integration of information. The focus of this paper is on asymmetric rotational components as the initial application area. To demonstrate the proposed cross-technology interoperability approach, a C-axis CNC turn–mill machine and a 4 axis CNC machining centre have been used with a simple test component.     

“Digi-code” - A micro computer program to digitize two dimensional figures and convert the data to CNC (Computer Numerical Control) Program

Engraving or machining free-form non mathematically defined shapes can be a complex task. “Digi-code” is a program to read and interpret coordinate location data describing parts or shape outlines. The coordinate data is converted directly to NC (Numerical Control) code to control a CNC (Computer Numerical Control) machine tool. This paper describes a technique to digitize contoured shapes and process the data directly to machine control code.     

STEP-NC based high-level machining simulations integrated with CAD/CAPP/CAM

With the development of manufacturing,numerical control(NC) machining simulation has become a modern tool to obtain safe and reliable machining operations.Although some research and commercial software about NC machining simulations is available,most of them is oriented for G&M code.It is a low-level data model for computer numerical control(CNC),which has inherent drawbacks such as incomplete data and lack of accuracy.These limitations hinder the development of a real simulation system.Whereas,standard for the exchange of product data-compliant numerical control(STEP-NC) is a new and high-level data model for CNC.It provides rich information for CNC machine tools,which creates the condition for an informative and real simulation.Therefore,this paper proposes STEP-NC based high-level NC machining simulations solution integrated with computer-aided design/computeraided process planning/computer-aided manufacturing(CAD/CAPP/CAM).It turned out that the research provides a better informed simulation environment and promotes the development of modern manufacturing.     

数控车削零件的仿真加工

本文介绍了数控车削零件的仿真加工技术。它采用CAXA软件生成NC代码,利用CAXA软件的CAM功能进行数控仿真,加载到VNUC仿真软件的计算机模拟机床里,模拟真实机床运动,最后通过数据线将G代码传输到实际机床,形成＂虚拟＋现实＂的仿真模式。这种模式弥补了CAD/CAM软件数控仿真的不足,将虚拟的机床运动与实际的数控操作融为一体,可使用户既掌握数控铣削加工的基本原理,又掌握数控系统操作的基本技能。     

A PNN self-learning tool breakage detection system in end milling operations

With the advance of technology over the years, computer numerical control (CNC) has been utilized in end milling operations in many industries such as the automotive and aerospace industry. As a result, the need for end milling operations has increased, and the enhancement of CNC end milling technology has also become an issue for automation industry. There have been a considerable number of researches on the capability of CNC machines to detect the tool condition. A traditional tool detection system lacks the ability of self-learning. Once the decision-making system has been built, it cannot be modified. If error detection occurs during the detection process, the system cannot be adjusted.To overcome these shortcomings, a probabilistic neural network (PNN) approach for decision-making analysis of a tool breakage detection system is proposed in this study. The fast learning characteristic of a PNN is utilized to develop a real-time high accurate self-learning tool breakage detection system. Once an error occurs during the machining process, the new error data set is sent back to the PNN decision-making model to re-train the network structure, and a new self-learning tool breakage detection system is reconstructed. Through a self-learning process, the result shows the system can 100% monitor the tool condition. The detection capability of this adjustable tool detection system is enhanced as sampling data increases and eventually the goal of a smart CNC machine is achieved.     

基于轮廓最优圆逼近方法的轮廓误差控制

设计并实现了基于轮廓最优圆逼近方法的轮廓误差估计模型,该模型克服了常规方法对于任意加工曲线,廓误差计算过程复杂、计算量大、难以应用到实时任务的缺点,通过实时读取数控机床的位置反馈值和插补器的指令数据估算出轮廓误差值,结合双模糊变论域自适应控制算法,应用于两轴数控系统并实时补偿各单轴控制器,实现对复杂加工过程轮廓误差实时估算并补偿。在实验数控机床上加工两种典型轮廓,对比实验表明,所提出的基于轮廓最优圆逼近方法的双模糊变论域轮廓误差控制方法能有效减小加工轮廓误差,有更高的轮廓精度。     

复杂曲面笔式加工的直接插补算法

复杂曲面笔式加工时的工具轨迹是位于曲面上的自由曲线轨迹．针对此类形式的轨迹，给出一种复杂曲面笔式加工时的自由曲线型刀轨的直接插补算法，即对位于曲面上以投影方式形成的任意自由曲线形式的刀轨进行插补计算，生成控制机床运动的指令．该方法的实现扩充了CNC系统的轨迹控制功能，提高了复杂曲面的加工效率．仿真和试切的结果证明算法可行而且有效．该算法也可以应用到整体曲面加工中．     

斜面矢量汉字CAD/CAM 研究与应用

提出了一种斜面矢量汉字的雕刻方法。根据相关文献总结出水平面上汉字雕刻流 程,再结合空间坐标旋转矩阵与C3 连续的空间七次Bezier 拟合曲线得出斜面上汉字雕刻的流 程。引入OpenGL,实现图形的任意旋转、缩放、平移,增强人机交互。实验结果表明,该方 法编写的软件界面友好,具有很好的健壮性,生成的数控代码在数控机床上运行稳定,达到了 预期的效果,提高了斜面汉字的加工效率,降低了加工误差。