研磨表面微观形貌的三维检测及Areal表征

介绍了三维表面微观形貌的检测方法,分析了采用高斯滤波提取基准中面的原理,针对研磨表面形貌的表征选取了一组Areal表征参数。运用原子力显微镜(AFM)扫描研磨工件的表面,采用高斯滤波提取基准中面进而分离出表面微观形貌的三维信息,在此基础上计算出表征参数值。试验表明研磨表面微观形貌呈现高斯分布规律,采用高斯滤波方法及所选的Areal表征参数能够有效地表征研磨表面的三维微观形貌。     

基于MEMS安保机构微弹簧测试方法的分析

介绍了S型微弹簧弹性系数的两种测量方法。在S型弹簧弹性系数计算公式的基础上,数字式显微镜试验方法通过对公式中主要影响因素的测量,计算出设计值与实际值的相对误差,并能够提出设计和加工的改善方法。用数字式显微镜方法进行大量的数据收集、数据整理、数据计算,是弹性系数研究的基础。为满足大批量弹性系数测试,在这基础上提出转台试验的测量方法。通过对转台试验原理的分析和验证,确定该测试方法能满足测试目的。     

基于 LSTM 的矩形纳米光栅 AFM 图像复原方法

原子力显微镜(AFM)利用探针与待测物之间的交互作用力进行成像,通过获取矩形纳米光栅计量标准器具的高分辨率成像得到相关的几何量参数并进行标定,实现从标准计量器具到工作计量器具的量值传递。在AFM扫描过程中,由于针尖的影响作用,使得扫描所获图像是探针和样品共同作用的结果,而不是样品形貌的真实描述。针对这一现象,本文提出了一种基于长短期记忆网络(LSTM)的AFM图像复原方法,该方法对通过膨胀法获得的仿真图像各扫描行进行训练,进而获得适用于矩形纳米光栅AFM图像复原模型。实验结果表明,针对线宽20 nm,高40 nm的矩形纳米光栅,经过该方法复原后光栅线宽的相对误差为7.40%,相较于传统的复原方法进一步提高了测量准确度。     

一种汽车LED前照灯散热器的性能分析及优化

为解决汽车用发光二极管的散热问题,将散热器的结构进行优化,对某LED车灯散热器进行参数化建模,利用仿真软件对每一组散热器进行热力学仿真分析,并结合汽车静止和行驶两种工况,通过改变不同参数的参数值研究该参数对散热器散热效能的影响。根据参数值—温度曲线选定最合适的参数值,以此对散热器进行优化设计。通过实物加工并设计实验平台对仿真计算结果进行实验,验证了优化参数的正确性。     

双成象单元扫描探针显微镜在纳米计量中的应用

研制了用于纳米计量的双成象单元扫描隧道显微镜一原子力显微镜，由扫描隧道显微镜参考单元和原子力显微镜被测单元组合而成。两者共用同一XY扫描器，同时对参考样品石墨和被测样品扫描成象。得到的石墨原子晶格参考图象与被测样品图象横向尺度相同，计数前者的原子晶格个数，即可精确测定被测样品图象的尺寸。利用本方法可对任何样品表面的超微观结构进行严格的纳米计量。     

椭圆型面联接原理分析

提出了一种新的型面联接曲线——标准椭圆曲线。首次定义了切力臂和法力臂两个概念 ,并推导了标准椭圆上该参数的计算公式 ,进行了椭圆联接的几何特性分析 ,并采用数值方法分析计算了接触应力的分布情况。     

基于Matlab的Hertz接触参数和主曲率差函数关系的拟合

借助Matllab分别对椭圆积分、椭圆率与主曲率差函数的关系进行拟合。通过实例计算,对由拟合法得到的Hertz接触参数值与对应的Hertz接触参数理论值及由线性回归法求得的值进行比较。结果表明,拟合法所得Hertz接触参数值与Hertz接触理论值更为接近,相对误差较小。     

双测头复合型微纳米测量仪的研制

针对当前微纳米测量中存在的大范围高精度测量及复杂微结构几何参数表征难题,基于多测头传感和精密定位平台复用技术,开发了一台具有多种测量尺度和测量模式的复合型微纳米测量仪。为使其具备大范围快速扫描测量和小范围精细测量功能,仪器集成了白光干涉和原子力显微镜两种测头,通过设计适用于两种测头集成的桥架结构及宏/微两级驱动定位平台,实现整机的开发。为保证仪器测量结果的准确性和溯源性,利用标准样板对开发完成的仪器进行了校准。仪器搭载的白光干涉测头可以达到横向500 nm,纵向1 nm的分辨力;原子力显微镜测头横向和纵向分辨力均可达到1 nm。最后,利用目标仪器对微球样品进行了测量,通过大范围成像和小范围精细扫描,获得了微球的表面特征,验证了仪器对复杂微结构的测量能力。     

基于激光多普勒技术的微悬臂梁机械特性的测量

介绍了一种微悬臂梁离面运动测试系统。结合显微激光多普勒技术,分析了用于间接测量微悬臂梁机械特性的方法,采用虚拟仪器技术建立控制系统,编辑器件激励和数据采集、处理软件,实现了对微悬臂梁的动态特性和杨氏模量、弹性系数等机械特性的测量。最后利用该测试系统对矩形、三角形微悬臂梁杨氏模量进行了实验研究,并计算了两种微悬臂梁的弹性系数。经实验证明,用该方法测量悬臂梁机械特性得到的弹性系数和杨氏模量误差小于7．5％。     

脉冲激光沉积薄膜的残余应力测量

为了测量脉冲激光沉积法制备的小面积薄膜的残余应力,并解决Stoney公式在特定情况下误差较大的问题,本文提出了一种基于悬臂梁结构和数值计算的薄膜残余应力测量方法。该方法以初始曲率为零的原子力显微镜探针作为衬底梁,在衬底梁上使用脉冲激光沉积方法沉积被测薄膜,并记录衬底梁在薄膜沉积前后的翘曲形貌变化,再结合薄膜厚度、衬底梁几何尺寸、所涉及材料的杨氏模量与泊松比等其他参数,借助数值计算对实验数据进行分析,得出被测薄膜的残余应力。使用该方法测出:基于脉冲激光沉积法在高温环境下制备的二氧化钒薄膜的残余应力为-340 MPa,与文献报道的结果相符。本文提出的基于悬臂梁结构和数值计算的薄膜残余应力测量方法具有适用范围广、准确度好、实验成本低的优点。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...