球头铣刀柔性铣削力建模与仿真

本文建立了球头铣刀柔性铣削力模型,研究了任意进给方向的球头铣刀铣削力模型,在模型建立过程中考虑了刀具偏心、刀具变形和刀具振动物理影响因素,推导出了综合物理因素影响下的瞬时切屑厚度表达式.在此基础上对球头铣刀瞬时铣削力进行仿真对比分析,验证了建立模型的正确性.     

基于CATIA的高速铣削用数控编程方法

阐述了高速数控切削的加工机理,分析与普通数控加工的区别,对高速加工机床和刀具进行分析、选择,针对被加工材料的零件特点,合理制定工艺方案,探究最佳切削参数,应用三维CAM系统进行数控编程,探讨出数控加工CAM高速铣程序,编制高速加工的最佳工艺方案,确定切削参数、切削效率等的最优化的关键技术。     

基于电子表格铣削参数计算模板的创建与应用

钻削、铣削和车削等机械加工中的切削用量均需根据不同的加工刀具、材料、表面质量以及加工工艺系统刚性进行选择、计算。本文充分利用电子表格的单元格引用与计算功能,创建了铣削加工中的基本切削用量、曲面精密加工行距、倒角加工增量角度计算模板创建,使零件加工切削参数的选择、计算更加合理、规范和方便。     

薄壁零件铣削加工的振动测试模拟分析

针对薄壁零件铣削加工过程中振动对精度的影响,进行薄壁零件铣削加工的振动模拟测试.结合响应面法建立薄壁零件铣削加工的振动信号输出模型,结合加工振动时间序列的特征重构结果,进行薄壁零件铣削加工的振动信号的小波尺度分解,通过多尺度小波融合方法,实现对薄壁零件铣削加工的振动模拟和输出型响应特征分析,通过振动频谱参数分析,实现薄...     

SolidCAM iMachining在车铣复合加工中的应用

X/Z/C这类车铣复合机床是价廉物美的实用机床,如何让这类机床发挥更大作用一直是很多企业经营者和企业管理者常思考的问题。本文就是给还在思考的企业经营者、管理者介绍一款操作方便、加工策略高效的加工软件——SolidCAM iMachining。iMachining不只是可以在铣床上发挥作用,就是在X/Z/C的车铣复合也表现出色。     

正交型车铣复合机床的构建及NC刀具路径的仿真模拟

正一、引言面对曲面加工的复杂性,多轴加工已经成为目前精密切削的趋势,为了实现复杂形状工件的加工,使工件在一部机床上就能完成多工序的加工,这样的机床称之为复合加工机床。复合加工机床的特性为结合多部传统机床的加工工序于一部机床上,由素材到成品,所有的加工流程只需一部机床来进行切削加工,如此将有利于少量多样的加工方式,更可进而搭配双主轴双刀塔,使工件双边都可进行加工,减少工件的装卸及移动次数,达到缩短加工周期、提升产品优良率以及降低生产成本等优点。     

VERICUT软件在五轴高速铣加工中的应用

一、VERICUT软件简介 VERICUT软件是美国CGTECH公司开发的数控加工仿真系统,由NC程序验证模块、机床运动仿真模块、优化路径模块、多轴模块、高级机床特征模块、实体比较模块和CAD/CAM接口等模块组成,可仿真数控车床、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、改进表面质量,检查过切、欠切,防止机床碰撞、超行程等错误;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;具有CAD/CAM接口,能实现与UG、CATIA及MasterCAM等软件的嵌套运行.     

Cimatron在高速铣削中的两个特殊策略

最近几年,随着航空航天、模具制造及精密微细加工等领域需求的日益广泛,高速切削技术已经得到了很大的发展和应用.高速切削不仅对机床、控制系统、夹具、刀具有特殊要求,而且也要求CAM软件优化刀具路径策略,螺旋或圆弧进刀、切削速度的连续和无突变以及无尖角刀具轨迹等是在各种刀具路径中都应尽量采用的,以保证切削过程的平稳和快速.     

参数化编程在曲轴偏心圆弧铣削加工中的应用

传统的曲轴曲柄圆、连杆颈圆弧加工是采用偏心夹具把工件调整到机床回转中心,以加工曲柄圆中心或连杆颈圆弧中心作为机床回转中心,通过车削加工的方式来完成加工,此加工方式加工效率低,偏心夹具调整时间长,工人找正工件误差大且工件找正时对操作者操作技能要求较高。为实现曲轴产业的高效加工,引入了新的加工方式,目前我们引入大型卧式车铣加工中心,可实现三轴以上联动铣削加工,该方式利用车铣加工中心三轴联动的方式,以曲轴主轴颈中心作为回转中心,加工刀具跟随曲轴曲柄圆和连杆颈做空间圆弧插补运动,以铣削的方式完成加工。当机床C轴（或A轴）做旋转运动,刀具在X轴和Y轴平面内以圆弧运动跟随机床旋转轴C轴运动时,编制程序时不容易找到编程所需的坐标点。要实现三轴以上加工程序的编制,目前主流的编程方法是采用编程软件编程,而编程软件编出来的程序会相当长,缺乏可读性,且不容易修改;如果手工编程,编程时间长,且需要每次作图才能确定其复杂的坐标点,如果绘制的图形不准确或坐标点精度不够,在程序运行时则容易出错及出现报警而导致程序的调试时间增长,影响加工效率及产品开发周期。     

PowerMILL在石油钻头体加工中的应用

石油钻头体如图1所示:该钻头体有五个空间方位的切削刃,每个切削刃上的工作部分有很多镶嵌金刚石刀片的盲孔,钻头体工作时就是依靠这些金刚石刀片进行切削。     

Neural control strategy of constant cutting force system in end milling

This paper discusses the application of neural adaptive control strategy to the problem of cutting force control in high speed end milling operations. The research is concerned with integrating adaptive control and a standard computer numerical controller (CNC) for optimizing a metal-cutting process. It is designed to adaptively maximize the feed rate subject to allowable cutting force on the tool, which is very beneficial for a time consuming complex shape machining. The purpose is to present a reliable, robust neural controller aimed at adaptively adjusting feed rate to prevent excessive tool wear, tool breakage and maintain a high chip removal rate. Numerous simulations and experiments are conducted to confirm the efficiency of this architecture.     

Optimization of process parameters for pulsed laser milling of micro-channels on AISI H13 tool steel

This paper focuses on understanding the influence of laser milling process parameters on the final geometrical and surface quality of micro-channel features fabricated on AISI H13 steel. Optimal selection of process parameters is highly critical for successful material removal and high dimensional and surface quality for micro-sized die/mold applications. A set of designed experiments is carried out in a pulsed Nd:YAG laser milling system using AISI H13 hardened tool steel as work material. Arrays of micro-channels have been fabricated using a range of process parameters such as scanning speed (SS), pulse intensity (PI), and pulse frequency (PF). The relation between process parameters and quality characteristics has been studied with experimental modeling. Multi-criteria decision making for material and process parameter selection for desired surface quality and dimensional accuracy is investigated using an evolutionary computation method based on particle swarm optimization (PSO).     

球头铣刀铣削表面形貌建模与仿真

为了研究铣削加工的表面形貌,文章给出了考虑刀杆柔性的螺旋刃球头铣刀的动态铣削过程模型,并基于广义加工表面创成理论、球头铣刀丸线模型和铣削运动模型,对球头刀动态铣削表面形貌进行了建模和仿真。     

A new approach for predicting and collaborative evaluating the cutting force in face milling based on gene expression programming

Cutting force is one of the fundamental elements that can provide valuable insight in the investigation of cutter breakage, tool wear, machine tool chatter, and surface finish in face milling. Analyzing the relationship between process factors and cutting force is helpful to set the process parameters of the future cutting operation and further improve production quality and efficiency. Since cutting force is impacted by the inherent uncertainties in the machining process, how to predict the cutting force presents a significant challenge. In the meantime, face milling is a complex process involving multiple experts with different domain knowledge, collaborative evaluation of the cutting force model should be conducted to effectively evaluate the constructed predictive model. Gene Expression Programming (GEP) combines the advantages of the Genetic Algorithm (GA) and Genetic Programming (GP), and has been successfully applied in function mining and formula finding. In this paper, a new approach to predict the face milling cutting force based on GEP is proposed. At the basis of defining a GEP environment for the cutting force prediction, an explicit predictive model has been constructed. To verify the effectiveness of the proposed approach, a case study has been conducted. The comparisons between the proposed approach and some previous works show that the constructed model fits very well with the experimental data and can predict the cutting force with a high accuracy. Moreover, in order to better apply the constructed predictive models in actual face milling process, a collaborative model evaluation method is proposed to provide a distributed environment for geographical distributed experts to evaluate the constructed predictive model collaboratively, and four kinds of collaboration mode are discussed.     

Position-oriented process monitoring in milling of thin-walled parts

Improving machining performance of thin-walled parts is of great significance in aviation industry, since most aviation parts are characterized by large size, complex shape, and thin-walled structure. Machining process monitoring is the essential premise to improve the machining performance. In order to improve the machining quality and efficiency, this paper presents a position-oriented process monitoring model based on multiple data during milling process, and corresponding solution is provided. Through obtaining the internal data set of the numerical control (NC) system during machining, it is possible to correlate the cutting position with monitoring signals including cutting force, acceleration, and spindle power. Then, process optimization is realized to improve the machining quality and efficiency based on the monitoring results. Machining tests are conducted on aircraft structural part as well as blade part, and the experimental results show this method provides a significant insight into the machining process of thin-walled part and contributes to the process optimization. By using feedrate optimization, time consumption for the rough milling process of one titanium alloy part reduced from 19.1 h to 14.4 h and the number of cutter consumption dropped from 5 to 3. And according to the result of position-oriented process monitoring, the machining strategies were optimized to reduce vibration and avoid chatter, thereby improving the machining quality.     

面向性能分析和优化的多业务过程仿真方法研究

针对业务过程性能分析和优化多侧重于对已部署的业务过程进行事后的性能监控、管理和数据分析等问题,详细分析了业务过程性能和仿真优化的研究进展,提出了一种与企业模型和工作流模型相兼容的集成化业务过程仿真建模方法（IBPSM）,并设计了支持IBPSM的多业务过程仿真工具（MBPST）原型系统。最后给出了一个具体的应用案例。实践表明这种事前的基于多业务过程仿真方法提供了业务过程性能的仿真分析与优化;同时可对优化后的业务过程进行快速部署,有利于业务过程的信息化实现。     

过程改进中评审活动的模拟分析

为定量研究评审效用,改进软件过程,通过模拟定量计算评审在过程改进中的效用。基于系统动力学方法分析评审活动和软件过程,建立软件过程模型。结合实例,证明了模型的正确性,通过模拟定量分析评审对项目工作量和工期的作用。模拟结果证明在一定范围内增加评审投入可以有效地增加工作效率,提高进度。以成本为优化目标,设置生命周期各阶段评审比例,通过自动模拟,得到最优评审工作投入,为实施软件过程改进提供量化支持。     

基于改进混沌粒子群算法的薄壁件铣削参数优化

为提高薄壁框体结构件铣削加工精度及加工效率,提出一种薄壁框体结构件铣削加工工艺参数优化方法.针对标准粒子群算法存在易陷入局部最优解,且不能自适应调整权重系数等问题,将混沌算法与多目标粒子群算法结合,建立了以铣削力和单位时间材料去除率为优化目标,以铣削4因素为优化变量,以机床主轴转速、进给量、铣削深度和表面粗糙度为约束条...     

基于Extend的舰船装备维修流程建模与仿真研究

通过分析一般舰船装备的维修流程,应用现有流程仿真软件Extend平台对舰船装备的维修流程进行建模和仿真。设置模型参数,根据模型运行结果分析模型设置的合理性,对维修的决策进行优化。     

基于FPGA的AFDX协议处理芯片设计

航空电子全双工交换式以太网（AFDX）是下一代航空数字网络的首选。AFDX的端系统可以保证数据在航电系统网络之间交换的安全性和可靠性,基于ARINC664规范的第7部分,提出了符合该规范的AFDX协议处理芯片的设计方案,对AFDX协议处理芯片中的关键模块进行了设计和仿真。