新型护理床椅的背板机构设计及分析

针对现有护理床椅背部模块难以实现护理床及轮椅两种使用姿态一体互变的难题,提出了一种新型背板机构。通过串联多个功能单一的机构组合成一个串联式背板空间组合机构,并分析其空间自由度以满足运动需求。将目标尺寸参数化,利用最小包容面积法得出支撑连杆与背板及支撑架铰链的最佳位置。根据背板机构的几何关系和静力学分析结果,采用额定行程与工作行程分别为175 mm、230 mm,最大推力为1 000 N的JC35D型电动推杆作为驱动装置。根据优化参数和驱动装置型号设计护理床椅的背板机构,并运用SolidWorks装配整体虚拟样机。应用Simulation有限元分析插件,对护理床椅护理床姿态下的背板施加安全载荷进行应力分析,验证了结构强度的安全可靠性。在护理床姿态下利用Adams View软件对机构进行静态侧翻仿真试验,验证了背板承受侧翻试验载荷时满足稳定性要求。     

座面可调电动轮椅的机构运动仿真

通过运动仿真,对座面可调的多功能轮椅进行机构设计。基于人机工程学及位姿分析,设计各构件尺寸。在MATLAB中建立轮椅运动学模型,通过仿真分析得到了各刚体关键铰接点的位移、速度、加速度等参数。将得到的运动学参数与轮椅的功能要求进行比较,对轮椅整车机构进行修正。所设计的轮椅能辅助残障者实现坐立、站立、平躺等多种姿态间的转变,也便于轮椅与其它康复设备的安全对接。多刚体运动学仿真方法能更直观进行机构功能分析,从而缩短设计周期。     

多功能护理轮椅床结构设计及机构运动分析

研究设计了一种实现支背、左右侧翻身、曲抬腿、抬臀、自动扶手等多功能于一体的全自动多功能护理轮椅床。通过对各部分功能机构的拟人化设计,合理优化空间布局,使整体结构紧凑;对主要机构的运动过程进行了Solid Works建模与仿真计算,结果表明,该护理轮椅床各机构运动角度及角速度变化具有较好的稳定性;最后通过对所研发的护理轮椅床样机进行实验,验证了护理床各功能机构及运动的有效性。     

姿态可调型智能护理轮椅床的设计

根据老年人和残障人士的身体状况,设计了一种能够实现姿态调整、危险预警和短信求助的智能护理轮椅床。介绍了护理轮椅床的机械结构和电气控制两部分,设计了床体折曲机构和可变轴距机构实现床椅姿态切换,设计了紧急情况报警电路和障碍物检测提醒电路。与市场上普通电动轮椅相比应用前景很广,实用性强。     

重心自调式多功能医护车的设计

该重心自调式多功能医护车利用齿轮齿条机构,使用者可轻松实现医护车、医护床及轮椅三者之间的转换。其最大特点是重心自调,通过螺杆机构传动带动平行四杆机构运动,平行四杆机构与齿轮齿条机构通过连杆联结,带动后轮前后运动,调整前后两轮之间跨距,保证运行的安全性。样车经试验测试,性能良好,适用于多种场合。     

一种可升降省力便携式轮椅设计

文章在分析目前市场上轮椅存在的缺陷基础上,设计出一种可升降省力便携式轮椅。该轮椅利用摇杆、摩擦棘轮机构、四杆机构构建出新型的驱动机构,通过摇杆往复驱动地轮运动,改变了用力形式,达到了省力的目的;采用叉杆机构、滑块机构和丝杠螺母副组成的升降机构使轮椅座位具有可升降功能,提高了残疾人的自理能力。通过创新设计,可升降省力便携式轮椅在传统轮椅基础上进一步扩展了使用功能,具有较高的实用价值。     

一种联动式护理床抬背机构的设计与研究

为解决现有护理床器械背板牵扯患者背部衣物而造成其不适难题,设计了一款护联动式理床抬背结构。该机构主要采用联动连杆滑块结构,实现患者起背过程中靠背板跟随患者背部的位姿变化而改变。依据矢量方程建立联动机构运动理论模型,并通过MATLAB仿真模块对联动机构进行了运动仿真实验,实验结果表明：仿真实验数据与理论计算结果整体趋势性较好,验证了结构设计的正确性和可行性。     

智能爬楼轮椅的结构设计与仿真分析

针对我国目前生产的轮椅爬越能力不强的难题,研究并设计一种适用于行动能力有缺陷的老年人和残疾人等人群的新型智能爬楼轮椅。首先,对智能爬楼轮椅的运动过程进行分析,并确定了设计方案包括动力驱动机构、行驶机构、行驶机构伸展装置、座椅调平机构等。其次,阐述了整体机构及工作原理,并用SolidWorks软件对智能爬楼轮椅进行三维建模。再次,对动力驱动机构和行驶机构等关键部分进行了理论测算,并通过Simulation、Motion模块进行静力学应力、位移特性和运动特性的仿真分析。最后,对智能爬楼轮椅的控制系统进行设计和简单分析。本智能爬楼轮椅具有爬楼能力强、自动调平等特点,可以克服现实生活中爬楼难的问题,可在医疗器械、助老领域推广应用。     

多功能轮椅机器人的结构设计及其性能分析

轮椅机器人可以为肢体残疾人群和老龄人群提供帮助,从而改变他们的生活质量。针对现有轮椅存在结构、功能单一的缺点,设计了一种多功能轮椅机器人,着重分析了其转向和升降性能,为轮椅机器人设计和制造提供了一定的理论基础。     

基于视觉测量的智能轮椅床自动对接

为了提高智能轮椅床系统对接的自主性,提出了一种基于视觉测量的自动对接架构。轮椅床对接过程分为远程导引阶段和近程对接阶段。在远程导引阶段,室内天花板视觉系统采集并识别轮椅上的新型人工标志,利用卡尔曼滤波(KF)的跟踪检测路标特征,继而采用P3P的视觉定位方法确定路标与相机的相对位姿,根据轮椅坐标系与远程阶段的世界坐标系的变换关系确定轮椅的姿态。在近程对接阶段,车载单目视觉系统采集对接目标的引导标志,利用引导标志的角点估计轮椅与床的相对位姿,最后根据实时的视觉反馈实现床椅的自动对接。多次实验结果表明所提出的视觉对接方法具有可行性和有效性。     

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...     

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.