孔系加工的宏指令编程与应用

以某型农用机变速箱壳体孔系为例,运用宏指令编写孔系的加工程序,并在加工中心上进行模拟仿真加工。运用宏指令编写孔系加工程序,不但减少了编程和计算工作量,而且简化了程序,提高了程序的通用性。     

数控车床程序编制中程序结构及指令应用分析

介绍了数控车床零件加工程序的编制思路,通过程序里换刀点、恒线速度、固定循环等相关指令的应用,根据加工工艺设定程序编写的先后顺序及主次结构,使得广大数控编程者能够高效合理的按照零件加工工艺设计来编写程序。     

宏指令G65在加工中的应用

宏指令编程像高级语言一样，可以使用变量进行算术运算、逻辑运算和函数混合运算的程序编写形式，能提供循环、判断、分支和子程序调用的方法。由于宏程序指令允许使用变量算术和逻辑运算及条件转移，可将相同加工操作编为通用程序，不仅使程序应用更加灵活，而且可大大精简程序量，使得编制相同加工操作的程序更方便、更容易，在一定意义上说，还提高了产品的制造能力和制造效率，增强机床的加工适应能力。     

基于宏指令的规则曲面数控加工程序的开发应用

阐述了数控加工规则曲面时的刀轨生成原理。基于FANUC-OMD系统的宏指令功能，运用该原理编写了一模具锥面的数控加工程序，实例应用表明这种编程方法不仅减轻了规则曲面手工编程的困难。而且使曲面加工质量更加容易保证。     

基于宏程序的非圆二次曲线数控车削编程与加工研究

非圆二次曲线是一种利用数学方程来描述轮廓形状的复杂曲线,在数控车削加工中,因数控车床系统没有二次曲线插补(编程)功能,致使在实际的生产过程中,非圆曲线零件的加工一直是个技术难题。为此,通过对数控车床系统插补原理和非圆二次曲线轮廓的近似数学模型进行分析研究,以非圆二次曲线中最具代表性的椭圆面的编程加工为例,提出了利用宏指令编写凹椭圆面加工程序的方法,实现了利用简单宏指令加工复杂曲线的目的,有效解决了实际生产中非圆二次曲线编程与加工困难的问题,拓宽了现有数控车床的车削范围。利用同样的原理,还可以推广至双曲线、抛物线、余弦曲线及正弦曲线等轮廓的生产加工。     

基于宏程序的曲线辊轴的数控加工

由正弦曲线和椭圆曲线回转而成的曲线辊轴,不能使用数控系统现成的循环指令直接编程加工。本例中采用宏编程和加工,首先解决了曲线平移后的坐标转换问题,并编写了完整的程序。该实例的坐标转换方法和程序编写方法同样适合其它非圆曲线轮廓的加工。     

SIEMENS 系统宏指令编程及应用

文章首先简要阐明了西门子系统宏指令程序的一些基础知识，然后通过在意大利MECOF公司制造的CS-1000加工中心（配SIEMENS-840C系统）上应用宏指令编程是简化加工程序，提高效率的有效手段。     

SIEMENS系统宏指令及变量R在数控编程中的应用

这里通过实例,介绍SIEMENS系统中的宏指令“@”及变量R在数控编程中的应用。采用宏指令及变量编程,使数控程序得到最大限度地简化,为解决一些特殊及复杂零件的数控编程问题提供了参考依据。     

SIEMENS系统宏指令及参数R在数控编程中的应用

通过实例,介绍SIEMENS系统中的宏指令"@"及变量R在数控编程中的应用.采用宏指令及变量编程,使数控程序得到最大限度的简化,为解决一些特殊及复杂零件的数控编程问题提供了参考依据.     

双二次关联曲面数控加工宏程序参数化编程研究

在数控铣削曲面加工中,经常会遇到由两条二次曲线所形成的关联曲面。如采用CAD/CAM软件对曲面进行数控编程,则程序冗长,调整不方便,故可采用宏程序的方式进行高级编程。以某零件曲面加工为例,介绍其宏程序的编写思路及相关说明,并将此曲面加工宏程序作为模板。在编写加工类似零件曲面程序时,均可以模板程序为基础,对其部分程序内容进行调整、修改,从而完成新零件的宏编程编写,实现编程的参数化。通过案例编程,总结出参数化编程时的注意事项。由于曲面加工宏程序采用参数化编程,提高了编程效率,在生产中可推广使用。     

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.     

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。     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

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...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....