基于AMESim和Simulink联合仿真的轧机压下系统分析

为实现轧机液压压下系统的电液一体化虚拟样机设计,提出基于Simulink与AMESim联合仿真技术的建模与仿真方案,根据轧机各辊之间的作用关系,建立了基于AMESim的轧机液压压下系统的质量弹簧模型和液压位置伺服系统模型,用MATLAB/Simulink建立了基于积分分离的PI反馈控制系统模型,最终构建了轧机压下系统联合仿真模型。在Simulink平台设计了干扰观测器抑制噪声方法,通过联合仿真分析,有效抑制了外部干扰噪声造成的不稳定性,提高了控制精度。联合仿真研究表明,干扰观测器能够抑制干扰噪声影响,该虚拟样机可应用于轧机压下系统分析。     

基于未知输入观测器的板带轧机液压压下系统故障诊断

为解决板带轧机液压压下系统故障辨识和定位问题,通过建立系统精确数学模型,应用未知输入观测器方法进行故障诊断和隔离。在建立系统状态方程的基础上对系统故障进行分析,确定了不同故障的方向矢量;应用未知输入观测器和广义残差集理论将系统故障作为未知输入,通过设计未知输入观测器组获得对特定故障方向具有鲁棒性的广义残差集进行故障诊断;仿真及试验验证了诊断方法的正确性和可行性。     

基于ADAMS与EASY5的大型模锻液压机联合仿真

针对某大型模锻液压机,介绍了运用多体动力学仿真软件ADAMS和多学科动态系统仿真软件EASY5实现联合仿真的一般方法.首先在三维建模软件Solidworks中建立液压机的三雏模型,然后导入到ADAMS中建立液压机的虚拟样机模型,同时在EASY5中建立液压机的液压系统模型,并且通过设计软件接口实现二者模型之间的动态数据交换.仿真结果表明,虚拟样机模型与液压系统模型之间实验了无缝联接,验证了该建模方法的有效性和实用性,并为实现机电液联合仿真提供了基础.     

绞车型升沉补偿模拟试验台虚拟样机

为弥补物理样机参数修改和试验结果观察不便、运行成本高等不足,开展了绞车型升沉补偿模拟试验台虚拟样机的研究。在Simcenter 3D motion中完成多体动力学模块建模,用AMESim完成液压控制系统建模,在主仿真平台MATLAB/Simulink中完成主控制器的建模,最后基于联合仿真接口实现3个软件的联合仿真,搭建了试验台的虚拟样机。仿真与试验结果对比表明,所建立的试验台虚拟样机模型准确,能较真实反映原物理样机模型,为进一步优化绞车型升沉补偿系统的设计参数和控制策略、提高补偿精度提供了验证平台,同时该虚拟样机搭建方法也为其他复杂机电液系统的仿真提供有益参考。     

飞机起落架收放系统动力学分析与试验

采用虚拟仿真及物理试验相结合的方法对飞机起落架收放系统性能进行研究。基于收放系统工作原理,推导了动力学数学模型,建立了结合起落架动力学和液压系统的多学科协同仿真模型,通过试验结果对虚拟样机模型进行验证。基于虚拟模型和试验平台对液压系统阻尼特性进行了分析,结果表明,联合仿真模型的压力曲线与试验实测数据吻合良好,为起落架收放系统提供了准确的设计方法。仿真及试验表明,阻尼孔径的缩小使压力变化缓慢同时振荡较严重,液压缸作动滞后较为明显。     

基于ADAMS与EASY5的某履带车辆制动系统的联合仿真

针对某履带车辆的制动系统,介绍了连用多体动力学仿真软件ADAMS和多学科动态系统仿真软件EASY5实现联合仿真的一般方法.先在三维建模软件Pro/E中建立履带车辆制动器的三难模型,然后导入到ADAMS中建立履带车辆制动器的虚拟样机模型,同时在EASY5中建立履带车辆制动系统的液压模型,并设计软件接口实现两种模型之间的动态数据交换.仿真结果表明,虚拟样机模型与液压系统模型之间实现了无缝链接,验证了该建模方法的有效性和实用性,并为实现机电液联合仿真提供了基础.     

冷连轧机液压压下系统动态特性分析

建立了1676mm四机架冷连轧机液压压下（HGC）系统轧制力方式下的控制模型，使用Matlab软件对此方式下液压压下系统的动态特性进行了仿真，确定该系统是稳定的。通过对影响液压压下系统动态特性因素的分析，找出了提高系统稳定性及响应性能的途径，并寻得了最优的PI控制参数。     

基于AMESim的连轧管机液压压下系统仿真研究

压下系统是连轧管机的关键设备,提高压下系统的性能是提高成品钢管质量的途径之一。在分析先进连轧管机对压下性能要求的基础上结合板带轧机中已普遍采用的液压压下装置,设计出可用于连轧管机的液压伺服压下系统,并利用AMESim这一方便、直观、高效的系统建模仿真工具建立了该液压伺服压下系统的仿真模型,对其动态特性进行了仿真和深入分析,为连轧管机液压压下装置的设计制造和性能改善提供了参考。     

基于联合仿真技术的深海采矿升沉补偿装置控制系统的研究

该文联合虚拟样机技术和控制系统仿真技术对深海采矿升沉补偿系统进行了设计研究,建立了基于液压动力源的升沉补偿系统采矿船多刚体机械动力学模型,并针对该模型设计了模糊自整定PID控制器。联合仿真研究结果表明,模糊自整定PID控制策略能很好地对升沉补偿装置进行有效的位移补偿控制,补偿率可达到40%~45%,从而提高了深海采矿系统的稳定性。     

基于虚拟样机技术的3自由度数控实验平台设计及联合仿真

随着现代数控技术的飞速发展,虚拟样机技术在数控机床的设计制造中已得到广泛使用。在充分研究虚拟样机技术的原理和应用方法基础之上,运用Solidworks软件建立了3自由度数控实验平台的三维立体模型,将模型导入ADAMS虚拟样机软件进行相关属性设置,然后使用Adams及Matlab软件对该3自由度数控实验平台进行预定轨迹规划及联合控制仿真,仿真结果证明了所设计的三自由度数控实验平台是合理可靠的。     

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。     

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....     

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.