基于微放电加工元件轮廓测量的探针制造

为了推动微加工和微机械技术的进步，微型零件轮廓和尺度测量方法的发展非常重要．可行方法之一就是使用带微探头的小型三维轮廓测量仪．这种仪器的探头必须针对某个零件的测量，按照最佳外形制造．微放电加工有着极小加工力，可用于各种探头的制造，本研究中用它进行探头加工．用这种方法制造了多种探头，将其装在基于扫瞄隧道显微技术(STM)的小型三维轮廓测量仪上．所制造的探头已被成功地用于各种微元件测量，结果表明此方法可行．     

汽车零部件制造技术的发展及应用

归纳了汽车零部件制造中的各种加工方法及工艺，对目前在现代汽车制造中所应用的最新的加工方法及工艺作出介绍和分析，为中国汽车零部件生产企业提供技术参考。     

Distributed machining control and monitoring using smart sensors/actuators

The study of smart sensors and actuators led, during the past few years, to the development of facilities which improve traditional sensors and actuators in a necessary way to automate production systems. In another context, many studies have been carried out aimed at defining a decisional structure for production activity control and the increasing need of reactivity leads to the autonomization of decisional levels close to the operational system. We study in this paper the natural convergence between these two approaches and we propose an integration architecture, dealing with machine tool and machining control, that enables the exploitation of distributed smart sensors and actuators in the decisional system.     

Neural networks for estimating the tool path length in concurrent engineering applications

This paper deals with the development of a neural computing system that can predict the cutting tool path length for milling an arbitrary pocket defined within the domain of a product design, in a computer numerically controlled (CNC) setting. Existing computer aided design and manufacturing systems (CAD/CAM) consume significant amounts of time in terms of data entry pertaining to the geometries and subsequent modifications to them. In the concurrent engineering environment, where even the designer needs information from the CAD/CAM systems, such time-consuming processes can be expensive. To alleviate this problem, a neural network system can be used to estimate machining time by predicting cost-dependent variables such as tool path length for the pocket milling operation. Pockets are characterized and classified into various groups. A randomized design is described so that the training samples that have been chosen represent the domain evenly. An appropriate network was built and trained with the sample pocket geometries. The analysis of the performance of the system in terms of tool path length prediction for new pocket geometries is presented.     

ANALYSIS OF THREE-DIMENSIONAL MACHINING USING AN EXTENDED OBLIQUE MACHINING THEORY

This paper presents an extended oblique machining theory applicable to the analysis of 3-D machining. Existing theories are evaluated to identify suitable formulations which are used with necessary modifications for predicting various quantities pertaining to cutting conditions of three dimensional machining. Actual chip flow angles extracted from measured forces, to account for the nose radius effect, are used, instead of available models, to predict important quantities such as shear plane angle, effective rake angle and shear flow angle. Experiments are conducted in the realms of conventional and high speed machining using AISI 4140 steel and aluminum 7075-T6 respectively with uncoated carbide inserts, and various process conditions pertaining to the cutting mechanics are calculated. The extended oblique machining theory is experimentally validated in predicting temperatures at the tool-chip interface and shear plane for conventional machining. Simulation results from the finite element modeling are used for verifying the shear stress and shear plane temperature predicted by the extended oblique machining theory.     

空间凸轮廓面侧铣加工及最小二乘优化刀位方法

通过对空间凸轮非等价加工方式下理论刀轴轨迹曲面微分几何特性的研究，表明加工空间凸轮工作廓面必然存在法矢异向误差。为寻求加工误差最小的最佳刀轴矢量，提出了数控侧铣加工空间凸轮廓面的方法。根据实际刀轴轨迹面是直纹面的性质，以NURBS直纹面重构理论刀轴轨迹面，采用最小二乘优化方法确定侧铣加工刀位，给出了理论加工误差模型，并通过实例的数值计算和加工实验结果证明了该方法的有效性。     

机械传动非线性因素对数控加工精度的影响

数控机床机械传动精度对零件的加工精度有较大影响。通过分析数控机床机械传动部件的非线性因素，得出影响数控机床定位精度和轮廓跟随精度的原因，并提出提高定位精度和轮廓跟随精度的措施。     

切削-挤压翅片管成形过程的研究

采用无屑切削-挤压成形技术加工翅片管。对翅片的成形过程和加工刀具的特点进行了研究,建立了翅片尺寸的理论模型;通过单因素试验,获得了主偏角、切削深度、进给量、切削速度等工艺参数对翅片尺寸的影响规律;以正交试验为基础,获得了翅片高度和厚度的经验公式。理论和试验研究表明,切削用量参数和刀具几何参数的精确匹配是翅片成形的关键。     

电化学机械光整加工表面形貌研究

提出了用于圆柱表面精密光整的夹心式电化学机械加工装置核心部件设计方案,探讨了主要工艺参数对表面质量影响规律。对采用这种新型加工方法所产生表面的轮廓高度特性、间距特性、形状特性、轮廓峰分布及表面波纹度进行了试验研究,结果表明电化学机械光整表面轮廓以高频小振幅波度为主要成分。     

Tool path generation for machining free-form pockets using Voronoi diagrams

Voronoi diagrams for closed shapes have many practical applications, ranging from numerical control machining to mesh generation. Curve offsetting based on Voronoi diagrams avoids the topological problems encountered in the traditional offsetting algorithms. In this paper, we propose a procedure using Voronoi diagram-based tool-path generation for machining pockets with free-form boundaries. A pocket can be bounded by 2D free-form curve elements that are differentiable twice. The procedure consists of three steps: