一种电动腰颈部锻炼装置的设计与分析

针对腰颈部疾患高发问题,提出了一种同时对腰背部和肩颈部的新型腰颈部锻炼装置。确定了工作原理并进行了详细的机构设计,通过建立运动学方程求出其运动学反解。在分析其三维运动功能的同时给出了腰背部锻炼效果的初步评估方法。制作了电动腰颈部锻炼装置的样机,并对其运动功能、腰背部和肩颈部锻炼进行了验证实验。结果表明,所设计的新型电动腰颈部锻炼装置具备办公椅、腰背部和肩颈部锻炼功能,其锻炼效果良好。     

一种新型的多足仿生机器人的机构设计与研究

提出一种新型的多足仿生机器人的运动机构,该机构具有运动灵活,自由度少的特点.利用D-H矩阵对该机构基本运动单元的运动学进行了理论分析,给出了运动学方程.基于虚拟样机技术对该运动学方程进行了仿真验证,结果表明运动学方程是正确的.建立了这种新型的多足仿生机器人的虚拟样机,并对其进行了虚拟样机的仿真研究.制作出了简易的一对足的实物试验机构.     

新型RR-RURU踝关节康复机器人机构的设计与分析

基于无耦合RR-RURU转动并联机构设计出一种新型踝关节康复机器人。利用螺旋理论对机构进行了运动输出特性分析和自由度计算;推导出机构动平台的姿态方程和角速度方程,讨论了机构满足运动学完全各向同性的结构条件;根据机构分支运动链的运动螺旋系的线性相关性,分析了机构的运动学奇异性并给出其奇异位形;研究了机构的工作空间,得到其可达工作空间的三维图形。绘制出新型踝关节康复机器人的CAD模型,利用临床医学步态分析数据（CGA）得到其输出角位移曲线,并对其动力学进行了虚拟样机仿真。研究结果为该新型踝关节康复机器人的样机试制提供了理论基础。     

携行式外骨骼下肢运动学分析与仿真

携行式外骨骼作为一种有效的人机耦合方式,能够为人体负重运动提供必要的支撑和辅助。下肢结构作为整个系统的核心组成,其运动轨迹的实现情况将会直接影响外骨骼穿戴舒适性和运动协调性。从运动学角度出发,对外骨骼下肢结构及自由度和动态稳定性进行了分析,利用坐标变换和D-H方法建立外骨骼下肢运动模型并实现下肢运动轨迹规划。利用Solidworks建立了外骨骼三维模型,将其导入Adams中构建虚拟样机模型进行运动学仿真。仿真结果验证了运动学模型及推导公式的正确性,为进一步研究携行式外骨骼打下了理论基础。     

一种四自由度并联机构运动学及传动性能分析

以2-RPU2-SPS并联机构为研究对象,首先借助螺旋理论对机构的自由度的数目和属性进行了分析,该机构可实现空间两转动和两平动运动(2R2T)。在此基础上对机构的位置正反解进行了研究,对于机构位置反解,给定机构独立运动参数可获得其显式表达;对于机构正解,可通过求解非线性方程组获得其数值解。另外,通过建立机构的雅克比矩阵,并利用机构支链输出传动效率指标对机构的运动学传动性能进行研究,为后续机构样机开发与实际应用奠定理论基础。     

一种复杂曲面打磨机器人自适应贴合柔性机构研究

针对工程中复杂曲面打磨困难的问题,提出一种能迅速贴合工件表面的柔顺混联式自适应机构,对其工作空间、运动学和动力学工作特性进行了分析研究。利用基于方位特征集的拓扑结构理论求解自适应机构的自由度、耦合度。利用数学应用软件对机构的参数进行数值计算,获得了自适应机构在抛光打磨过程中的工作特性曲线和工作空间模拟图。建立自适应机构的样机模型并进行样机实验,分析了在对模拟的复杂工件曲表面加工时的运动学和动力学特性,实验得出本设计相对传统机型的优势。     

一种新型的空间仿生机械腿的机构设计与研究

调查目前仿生机器人的研究现状,提出一种空间仿生机构和可变形腿运动机构。该机构具有运动灵活、自由度少、适应性强的特点。利用D-H矩阵分析法和直角坐标分析法对该机构的基本运动单元的运动学进行了理论分析,并给出了运动方程。利用SolidWorks三维造型软件进行了机构的三维建模与干涉检查,利用ADAMS软件建立了这种新型的仿生机器人的虚拟样机,进行了基本运动单元的运动学仿真。根据机构的位移矩阵变换原理,进行了轨迹的对比分析,提出可变形腿机构。     

球面5R并联机器人运动规划方法及实验

针对空间矢量定位、球面加工的任务需求,优化并加工了一台球面5R并联机构样机,结合样机的"PC+PMAC卡"的主从分布式控制系统,利用C#语言开发了上位机的控制软件。基于运动学反解,利用球面机器人工作空间球对称的特点,采用坐标变换的方法将组合型轨迹规划曲线应用于机构末端的路径规划,在样机的有效工作空间内对球面上任意两点间的圆弧运动路径进行规划;最后通过ADAMS软件运动仿真及样机实验研究,验证运动学分析和路径规划方法的正确性。     

足式机器人腿部零动力元机构设计及运动学分析

为降低足式机器人腿部质量,提高机器人动力学特性,同时避免电机的频繁往复运转,基于4杆机构的运动传递原理,设计了一种足式机器人腿部机构,将大腿小腿的驱动电机布置于机器人腹部,实现了腿部零动力单元化。基于D-H法,推导了腿部机构的运动学模型,利用Matlab进行了运动学数值求解,通过与ADAMS虚拟样机仿真结果的对比,验证了理论推导的正确性。基于运动学模型,通过计算对比分析4杆机构各构件不同杆长条件下,腿部关节的运动学响应关系,并对足端轨迹进行了对比分析,确定了腿部机构杆长的最佳尺寸。研究表明：将曲柄摇杆机构应用于足式机器人腿部机构的驱动,可充分发挥4杆机构的运动优势,同时避免急回特性对构件运动产生的不利影响,从而提高机器人的行走效率,为后续实验样机的设计与搭建提供了参考。     

一种三自由度并联踝关节康复机构

在分析现有踝关节康复机构的基础上,提出一种基于3-UPU并联机构的新型踝关节康复机构,该机构具有3个自由度,能够实现踝关节的旋前/旋后、内翻/外翻运动,并且该机构的转动轴线可实现高度和角度方向的调节,从而使机构转动轴线与人体踝关节运动轴线更好的吻合,给患者带来更好的康复效果。求解了机构的自由度,运动学反解,并根据踝关节康复要求对机构尺寸进行确定,进一步求解了机构的工作空间,对机构的运动学进行了仿真验证和样机运动试验。     

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...     

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.     

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....     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.