双层预紧式六维力传感器及其静态标定

针对基于传统Stewart结构六维力传感器在解耦、刚度等方面性能的不足,设计并研制一种双层预紧式六维力传感器,并对其进行静态标定试验研究.所设计的六维力传感器采用球窝锥头式球面副代替传统球副,有效地减小了球副的摩擦力矩,另外测量分支只承受压力,消除了力在换向时对接触球面的冲击,提高了整体刚度.基于螺旋理论推导出传感器所施加外力与测量分支轴向力之间的映射关系,进而说明预紧式六维力传感器的测量原理.采用最小二乘线性化标定方法对传感器进行静态解耦和测量误差分析,推导出传感器的标定矩阵和误差矩阵.研制出双层预紧式六维力传感器样机,并进行静态标定试验.经过标定试验,该传感器各方向最大非线性度误差低于满量程的1.17％,最大耦合误差低于满量程的1.82％.试验结果表明双层预紧式六维力传感器具有很高的测量精度,可用于工业生产中对六维力测量要求较高的场合.     

基于神经网络的多维力传感器静态解耦的研究

提出了基于人工神经网络进行多维力传感器静态解耦的方法。维间耦合是制约多维力传感器测量精度的主要因素，为克服传统线性解耦方法的局限性，利用BP神经网络的强非线性逼近能力研究了多维力传感器的非线性静态解耦。以研制的微型5维指尖力／力矩传感器为对象进行了解耦实验，结果表明，与基于最小二乘的线性解耦方法相比，提高了解耦精度。     

多维车轮力传感器静态解耦的研究

传感器的静态耦合是制约多维车轮力传感器（WFT）测量精度的一个主要因素，WFT的耦合主要为线性耦合。针对标定WFT时不能施加单维力的情况，用迭代法实现了线性解耦。时WFT的耦合率矩阵进行了计算，并进行了耦合分析。对汽车道路试验数据进行了解耦，并与不解耦的结果进行了对比。结果表明：经线性解耦后，WFT的耦合误差基本被消除，测量精度得到了提高。     

基于曲线拟合的正交并联六维力传感器静态标定

针对六维力传感器在本身制造、安装和工作条件等因素的影响下造成输入与输出之间并非处于理想线性关系的问题,提出一种新的基于最小二乘的曲线拟合静态标定算法,该算法得到的六维力传感器静态标定结果与以往算法相比精度更高。首先,推导正交并联六维力传感器的数学模型。然后,介绍最小二乘法以及对最小二乘拟合进行理论分析。其次,提出基于高次曲线拟合的静态标定算法,建立六维外力/力矩与分支输出电压之间映射关系的拟合多项式,并求得曲线拟合系数矩阵。最后对正交并联六维力传感器进行静态标定试验,来验证该标定算法的正确性和优越性。     

机械解耦自标定并联六维力传感器设计及仿真

针对传统多维力传感器研制后均需繁冗的加载标定这一现状,提出了多维力传感器“自标定”设计理念,通过钢球滚动机械解耦,设计了一种弱耦合全压向力自标定正交并联六维力传感器结构。论证了该六维力传感器的滚动解耦原理,分析了其自标定原理。基于螺旋理论建立了该六维力传感器理想数学模型,计算得到其一阶静力影响系数矩阵。考虑分支弹性变形,基于高次超静定结构力学求解原理,对该六维力传感器进行了受力分析与仿真计算,结合数值算例论证了其自标定特性,从而为该新型六维力传感器的研制奠定基础。     

新型过约束正交并联六维力传感器测量模型与静态标定试验

面向航空航天领域对重载大吨位多维测力传感器的急需,通过引入冗余测力分支,提出一种适用于重载测力场合的新型过约束正交并联六维力传感器结构,在提高传感器结构刚度和承载能力的同时有效抑制了关节摩擦对多维力传感器测量精度的影响。基于螺旋理论,推导得到了该并联传感器一阶静力影响系数矩阵,建立理想状态下该新型过约束正交并联六维力传感器测量数学模型。考虑各测量分支的初始预紧力与刚度,基于传感器静力平衡方程与补充建立的位移协调方程,推导建立考虑初始预紧力与分支刚度因素下该新型过约束正交并联六维力传感器测量数学模型。在此基础上,设计并研制该新型过约束正交并联六维力传感器样机,搭建传感器加载标定与信号采集及处理试验系统,对新型过约束正交并联六维力传感器进行了加载标定试验。根据试验结果计算了传感器测量误差矩阵,分析得到了传感器测量精度,从而为重载过约束并联六维力传感器的开发与应用提供了参考。     

一种三梁结构六维力传感器设计与研究

设计了一种三梁结构六维力传感器,详述了传感器弹性体在各载荷分量作用下应变梁的应变情况,并通过合理的应变片组桥电路将各载荷分量信号转换成电压信号输出。提出了一种简化计算解耦矩阵的方法,最后通过有限元仿真技术施加10组载荷,求解并验证解耦矩阵,结果表明该六维力传感器设计方案和解耦方法完全可行。     

Stewart型六维力传感器的静态解耦实验

本文研究了一种Stewart型机器人六维力传感器的静态解耦实验问题，为该种六维力传感器的实用及其产业化奠定基础，并且介绍了传感器测试原理、标定装置，进行静态标定与解耦实验。实验结果分析表明，该六维力传感器解耦性良好，满程测量精度能达到2％。     

大量程柔性铰六维力传感器静态解耦的研究

为提高大量程六维力传感器的测量精度,提出了一种新型的六维力传感器非线性静态解耦方法,该方法结合混合递阶遗传算法和小波神经网络的优点,采用递阶遗传算法与最小二乘法分别对小波神经网络隐层结构参数以及输出层权值进行优化,再将优化后的小波神经网络模型用于六维力传感器非线性解耦.建立了基于混合递阶遗传算法和优化小波神经网络的六维力传感器非线性解耦模型,设计了基于混合递阶遗传算法的小波神经网络结构及参数优化算法,给出了六维力传感器非线性解耦的具体实现流程.以最新研制的6-UPUR大量程柔性铰六维力传感器为对象进行实验,结果表明,采用该方法六维力传感器的Ⅰ类误差和Ⅱ类误差分别为1.25％和2.59％,比采用BP和RBF神经网络方法的测量精度高.     

基于BP神经网络的三维力传感器静态标定方法研究

三维力传感器作为测力平台的核心元件,其测量精度直接影响测力平台的使用效果,而维间耦合问题是影响精度的主要方面。文章首先讨论了三维力传感器传统的静态标定方法在消除耦合误差方面的应用,并在方法缺陷分析的基础上,提出了新的三维力解耦方法——基于BP神经网络的解耦方法,继而对两种方法进行误差分析,验证了神经网络方法在多维力传感器解耦中的可行性和优越性。     

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....