焊管轧辊设计新方法

采用KBE（基于知识的工程）技术,将轧辊设计的相关知识和设计人员在长期工作中积累的经验运用到轧辊设计中,建立了基于知识的轧辊设计系统的框架体系和轧辊设计的知识库,开发了基于知识的焊管轧辊设计系统。提高了轧辊设计的智能化程度以及设计的质量和效率,减少了设计对设计人员经验的依赖。     

支持并行设计的约束知识管理

设计约束知识是支持并行设计知识的重要组成部分,通过设计约束知识管理与并行设计的有效集成,可以提高并行设计的效率和效果。分析了并行设计约束知识的组成,以约束网建立了设计约束知识之间的关系,支持并行设计活动中设计约束知识的使用。对设计约束知识管理相关技术进行了总结,构建了支持并行设计的约束知识管理框架,讨论了知识管理系统的主要功能,为系统的开发提供了基础。     

基于模块化设计的柔性装配工装关键技术研究

在飞机柔性装配工装设计制造过程中引入模块化设计技术能够极大地促进飞机柔性装配工装的发展。对模块化设计的关键技术——模块化设计流程、专用模块设计、通用模块设计和模块接口设计进行了详细的阐述,并根据壁板组件柔性装配工装、襟翼柔性装配工装等的设计实例,介绍了模块化设计在飞机柔性装配工装设计中的具体应用,以期对基于模块化的柔性装配工装设计提供参考。     

基于SecoMAN的液压插装阀集成块的设计

介绍了利用三维设计软件SecoMAN设计插装阀集成块的优势。SecoMAN是在二维图中进行油路设计并通过三维透视图观看设计,因此可以得到快捷、合理的设计。缩短了设计时间,保证了设计准确性,提高了设计效率。     

再制造设计的创新理论与方法

再制造设计是提升再制造效益的重要方法途径,是对产品设计和工程设计的创新补充,属于新兴的设计内容。以再制造设计概念与特征分析为基础,提出了面向再制造创新设计的产品梯度寿命设计理论、再制造性设计与评价理论、产品再制造工程设计理论,研究分析了面向再制造的产品材料设计、产品结构设计、再制造产品生产设计等再制造设计的新内容,为再制造设计的理论研究和方法应用提供了借鉴。     

汽车管路胎具设计系统的开发与应用

在分析胎具设计的特点和要求的基础上,提出UG平台下进行胎具设计的一般方法,并以UGNX5.0作为平台,开发出基于胎具设计方法的汽车管路胎具智能化设计系统。利用该系统可实现管路胎具自动化设计,并可模拟设计过程,预测设计缺陷。     

汽车覆盖件拉伸模设计中注意事项

阐述了汽车覆盖件拉伸模设计过程的几个细节问题,如拉伸筋设计、导向方式设计、顶料方式设计、平衡块设计、定位元件设计、排气孔设计、到底印记设计、钢料拆分原则等,从而减少在汽车覆盖件拉伸过程中发生起皱和拉裂的可能性。     

虚拟设计与传统设计的定量化设计周期对比

机械产品设计决定了75％～80％的产品成本,并在很大程度上决定了生产产品的效率和产品的使用性能。定量化的评价虚拟设计周期一直是困扰产品设计者的难题。文章应用产品设计计划评审技术（PERT）对机械产品应用虚拟设计和传统设计的设计周期进行定量化对比。通过对比,机械产品分别采用虚拟设计与传统设计,虚拟设计周期明显缩短,缩短设计周期达40％以上,且同样设计周期的情况下,采用虚拟设计完成设计的概率比采用传统设计要高得多。     

基于公理化设计理论的供应链设计

阐述了企业实施供应链管理的重要性,介绍了供应链管理所面临的挑战.提出了基于公理化设计理论的供应链设计方法,降低了供应链设计的复杂性,给出并分析了供应链设计步骤.应用公理化设计方法,供应链设计目标和策略之间的"之"字映射与层次化分解过程保证在设计过程中以适当的顺序作出合理决策.公理化设计为供应链设计开发提供了基本原则和指导框架.     

浅析双线货运索道侧型设计理念

线路侧型设计是索道设计的关键,一条索道运行是否成功,与线路设计是密不可分的。传统设计理念对线路强调局部性设计,对整体性、全面性设计并不看重。本文从工程实例出发,提出整体性与局部设计结合,探索一条线路设计的新思路。     

A scanning tunneling microscopy tip with a stable atomic structure

A single stable adatom on a {110}-type plane of a tungsten tip is created via field-evaporation in a field-ion microscope (FIM) operating at room temperature. This single adatom has sufficient surface mobility at room temperature and migrates, in one-dimension, along a <111>-type direction toward an edge of a {110}-type plane, due to the existence of an electric field gradient. The plane edge has a higher local electric field than its center, since it has a higher local geometric curvature. This result implies that the stable position of a single adatom during a scan of a scanning tunneling microscope (STM) tip on a surface is at the edge and not at the center of a {110}-type plane at room temperature. Therefore, the electron wave function of a tip is not symmetric and this fact should be taken into account in a careful analysis of STM images. Also a tip with a dislocation emerging at a {110}-type plane is suggested as an improved STM tip configuration, as the step at the surface, created by the intersection of the dislocation with it, is a perpetual source of single adatoms.     

Identification of machine–tool–workpiece system dynamics

The aim of this paper is to present a method to identify the dynamics of a structure composed of a milling machine, a tool and a workpiece. The excitation is obtained as a result of the interrupted cutting of a narrow workpiece width and single tooth milling operations. This provides a pulse-like cutting force. The three components of the cutting force and the relative motion between the tool and the workpiece are measured simultaneously. A method was developed to determine the nine terms of the structural transfer matrix under a single cutting operation and without any assumption on the excitation direction. The proposed method is experimentally validated.     

捷联惯性制导系统的电路设计

通过对捷联惯性制导与平台惯性制导之间差异的分析，讨论了在进行捷联惯性制导系统的电路设计时所应注意的问题，在此基础上，用C32 DSP和可编程逻辑器件，设计了一个捷联惯性制导系统的电路。     

Influence of discharge current on machined surfaces by thermo-analysis in finish cut of WEDM

In finish machining of wire electrical discharge machining (WEDM), the discharge current has distinct influences on the machined surface. In order to study the differences in surface morphology under various pulse durations, thermo-analysis was carried out to investigate the mechanism of erosion of the workpiece material using the finite element method. Additionally, related single discharge experiments under different pulse energies were performed. Under the same discharge energy, the comparison of analytical and experimental results shows that a discharge current with a short-duration pulse and a high peak value removes the workpiece material mainly by gasifying, while a discharge current with a long-duration pulse and low peak value removes the workpiece material mainly by melting. It was also found that surfaces machined by a discharge current with a short- and long-duration pulses would have similar roughness values when the pulse energies were almost the same and were high enough; however, the surface morphologies would be totally different. A discharge current with a long pulse duration and a low peak value could not produce craters on the workpiece surface when the pulse energy was reduced to a certain value. However, a discharge current with a short pulse duration and a high peak value could produce clear craters on the workpiece surface. This indicates that a discharge current with a short pulse duration and a high peak value can generate better surface roughness, which cannot be achieved with a current with a long pulse duration and a low peak value.     

Stability analysis and motion planning strategies with fuzzy coordinator and learning for mobile base robotic part macro/micro-assembly tasks

This paper addresses problems of a mobile base robot’s part assembly. This process can be broken down into two phases. First, a macro-assembly, bringing a part to an assembly hole or a receptacle (target) for a purpose of a part mating. For the macro-manipulation task, a stability analysis of a mobile base robot subject to disturbances, such as an external impact force and torque as well as a tipping movement, is discussed. The mobile robotic system is stabilized by balancing the system moment through a fuzzy coordinator. Simulations are performed by applying external forces and torque to the system and adding disturbances to the mobile base’s tipping movement. Second, a micro-assembly, mating a part with a target. For the micro-manipulation task, two learning methodologies are presented. First, a learning strategy to minimize the entropy, uncertainty, and eliminate unneeded events in the plan related to avoiding jamming is described. An entropy function, which is a useful measure of the variability and the information in terms of uncertainty, is introduced to measure its overall performance of a task execution related to the part mating. Next, a fuzzy stochastic learning method, based on the probability of a fuzzy set and a modified distance metric, to update the probability of a plan composed of fuzzy events used for the part mating task is introduced. The degree of uncertainty associated with the fuzzy event of plan is used as an optimality criterion, or cost function, e.g. minimum Hamming distance, for a specific task execution. The above techniques are applicable to a wide range of mobile robotic tasks including pick and place operations, maneuvering around workspace, manufacturing, part mating, or complex assembly tasks.     

通过吉田-上森模型进行回弹预测和利用Jstamp进行回弹补偿的研究

考虑到由塑性应变导致弹性模量发生变化,作者为商业软件LS-DYNA专门编制了一个子程序吉田-上森模型,然后分别使用实体单元和壳单元对两个冲压件进行回弹模拟。为制造与设计的形状和尺寸相一致的冲压件,提出了回弹研究的新功能和回弹补偿算法并集成到钣金成形仿真软件JSTAMP中。最后,研究了回弹的原因和介绍了使用JSTAMP对车身底座横梁板执行回弹补偿的过程。     

Nondestructive evaluation of surface defects under dry/wet environment by the use of photoacoustic and photothermal electrochemical imaging

Nondestructive evaluation of surface defects fabricated on a metal plate has been performed by the use of a photoacoustic scheme and a photothermally-induced electrochemical detection scheme. An Ar laser beam is modulated with a mechanical chopper and is focused on a metal sample plate with a microscope objective lens. The laser beam is scanned with a pair of computer-controlled optical scanners. The principle of a photothermal electrochemical scheme is to detect an electrochemical current change caused by laser heating, instead of the sound wave detection in a photoacoustic scheme. A columnar hole fabricated on a metal sample surface was studied for each detection scheme under a dry/wet environment.     

Dynamics of boring processes: Part III-time domain modeling

This article presents a mathematical model and a computational algorithm for the time domain solution of boring process dynamics. The model is developed in a modular form; it includes a workpiece geometry and surface topography module, a kinamatics and tool position module, a dynamic chip load module, a dynamic cutting force prediction module and a structural dynamics module. The time domain model takes cutting process parameters, tool and workpiece geometries and modal parameters of the structure as inputs. It predicts instantanous cutting forces and vibrations along the machining time, and machined workpiece topography as outputs. Some of the simulated and experimental results for various cutting conditions are presented and compared for validation purposes.     

Superfinishing and grind-strengthening with elastic bonding system

This paper presents with a new grinding strategy for a surface superfinishing and a grind-strengthening of the surface layer of steels in a single grinding step. To grind-strengthen a surface layer both abrasive material removal and a plastic deformation are needed. This combination together with an appropriate grinding wheel design offers the possibility to ensure high precision surfaces with a consistent quality finish that meets the highest standards. This kind of grinding process could be applied to bearings, for example. During the run-in period, the initial contact surfaces change until they stabilize to a running-in condition and have a new surface topography. Grinding with the new process strategy leads to benefits because a grind-strengthened surface layer eliminates initial wear and abrasion within the system, reduces surface finish roughness, extends fatigue strength, and reduces risk of part failure during operation.     

Identification of Heat Transfer Coefficients by Use Conditions of Quenching Oil

Heat transfer coefficients of the quench medium are necessary for heat-treatment simulation. Cooling characteristics of quenching oil vary with kinds and usage greatly. Users are selecting oil solutions that come up to their desired hardness and quenching distortion requirements. In particular cooling performance rises by agitation and decompression. Therefore we identified a heat transfer coefficient by usage and kinds of quenching oil. Cooling characteristics are different greatly by a kind of quenching oil. A difference of a cooling characteristic by a kind of oil depends on a temperature range of a boiling stage and the maximum heat transfer coefficient mainly. On the other hand, in a convection stage, there are few changes in a boiling stage. Even if quenching oil temperature is changed, heat transfer coefficients do not change greatly. When quenching oil stirred, heat transfer coefficients of vapor blanket stage and a convection stage rise, but there are a few changes in a boiling stage. When quenching oil is decompressed a temperature range of a high heat transfer coefficient moves to the low temperature side. In addition, a heat transfer coefficient in a vapor blanket stage comes down. For precision improvement of heat-treatment simulation, it is important that the heat transfer coefficient is calculated in conformity to the on-site use reality.