结合贴片机智能化发展需求,针对当下数字孪生研究缺乏对孪生模型逼近程度及实时性的关注的问题,提出了一种将半物理仿真系统作为实现孪生端模型的技术框架的思路.同时考虑成本,提出以Windows系统近似模拟实时系统的方案并对此低成本方案进行实时性测试,结果表明此孪生端模型方案有效.通过WPF框架完成对数字孪生平台上位机软件的开发,实现对实物贴片机、孪生端模型、上位机软件三位一体的通讯连接、数据传输,其中通过嵌入Webview2控件完成对实物贴片机的模型仿真驱动.

针对目前电子行业中许多中小型企业、高校或个人有对电路板进行小批量贴片的需求,以及市场上缺少工业化实用性设备的问题,该文提出了一种小型化低成本的桌面型贴片机.首先为桌面型贴片机设计了一种紧凑型结构,完成了视觉系统的选型;然后提出一种上视相机的专用标定方案;最后提出并完成了基于几何外形特征的芯片校准方案,为后续紧凑型桌面贴片机的工业化和成熟化奠定基础.

针对四节伸缩臂的高空作业平台,以变幅油缸受力、伸缩臂受力最小为优化目标,引入7个设计变量来表示变幅三铰点的几何位置参数,建立了对高空作业平台变幅三铰点优化的数学模型,并利用遗传算法来寻找最佳的设计变量值.优化结果显示,优化后的油缸受力和伸缩臂受力得到了一定的改善,对高空作业平台的计算机辅助设计提供了一定的参考价值.

In order to increase the accuracy of tool edge tooth profile,a new method named envelope method for calculating tool edge tooth profile is used.According to forming principle of the double-enveloping hourglass worm,a mathematical model of worm gear tooth surface is established by using the envelope method and the tooth profile equation of the worm gear in the middle plane is derived,which is the tool edge tooth profile equation.The tool edge tooth profile is drawn with MATLAB software.Based on the idea of reverse engineering,a 3D model of worm is established with Pro/E software.The result shows that the worm cogging in the axial section is the same as tool edge tooth profile.

In modern construction engineering,the construction scale and speed is increasing,andthe demand for concrete is also in-creasing,However,the productivity of a single concrete mixing station is limited and can not meet the needs of modern construction.Espe-cially when multiple construction sites in the same area are constructed at the same time.Supply of a single concrete mixing station be-comes stretched.In order to meet the needs of modern construction engineering for concrete,because of the importance of reducing trans-portation costs,it presents a new mode of concrete supply based on cooperative supply and the reasonable choice of the cooperative part-ners.According to the mathematical description of the problem,cooperative distribution model is established for designing the optimal dis-tribution scheme of cooperative supply.By building the table of co-ordination of supply and demand,and usingthe table dispatching method,the problem is solved.Finally,in an example,the optimal distribution scheme of cooperative supply is obtained.

为了研究施工升降机齿轮齿条传动的接触强度，对其进行非线性状态下接触问题的有限元分析。在分析过程中，借助Pro/E建立精确的参数化三维实体模型，保证了有限元分析模型的精确性，同时引入了牛顿—拉普森算法求解非线性问题理论求解齿轮齿条啮合位置的接触应力。将仿真结果与理论计算结果相比，显示误差在允许范围内，可以作为齿轮齿条接触强度计算依据。

为了解决复杂的优化问题,提出了使用MATLAB优化工具箱处理优化问题的方法.主要介绍了基于优化工具箱求解非线性问题的步骤和方法,最后给出车床主轴优化实例,验证MATLAB优化工具箱在求解复杂优化约束中的方便、简单、有效性,对使用优化工具箱解决复杂优化问题具有重要的参考价值.

为实现振动压路机的快速设计,通过Visual C#集成开发环境开发出一套基于SolidWorks平台的振动压路机CAD系统.实现了利用SolidWorks API函数参数化创建振动压路机零部件模型和自动装配的功能.最后以振动压路机的激振器设计为应用实例详细介绍了振动压路机CAD系统的应用.

选取三个存储温度(90℃,120℃,150℃)对3种SBS改性沥青(E+ S-YS,E+S-YY,S+S-YY)进行加工存储,应用沥青常规试验与重复蠕变试验,进行了感温性、高温性能、低温性能的试验研究,通过分析研究结果,提出了相应的存储改性沥青的温度推荐值.

基于物理的流体动画技术一直是计算机图形学领域研究的重点,但是之前大多数研究一直针对的是如何对流体模拟进行加速,而文章对于如何更加精细的模拟流体做了全面的综述,重点从模拟方法、界面重构、边界控制及算法优化方面做了介绍与分析。

圆形的特征易于提取,摄像机标定通常会选择圆形做为靶标.要准确找到靶标圆圆心像点的位置对标定是至关重要的.传统的做法是对圆形的像椭圆进行拟合,用椭圆的形心代替像点,这种做法不可避免地引入了模型误差.文中提出了一种基于包围盒的计算模型,理论上消除了这种模型误差.最后,通过实验验证,此计算模型有较高的精度.

我国日益增长的交通量和严峻的气候变化等因素使得目前沥青混凝土路面很难满足行车安全、舒适、养护费用小等要求。在沥青混合料中添加纤维材料,可提高路面功能强度,为此本文通过对比掺加与不掺加玻璃纤维的沥青混合料各项技术性能如高温稳定性、低温抗裂性和水稳定性能,分析了沥青混合料中添加玻璃纤维的优越性。

This paper makes use of 3D finite element analysis to calculate the structure of perpetual semi-rigid base asphalt concrete pavements,and gets the conclusion that,to meet the requirements of perpetual pavements,perpetual semi-rigid base asphalt concrete pavements must have thicker asphalt overlay.

Based on experiment of per actual project of maintaining a certain highway with micro-surfacing construction technology in the northern areas of China,this paper analyses the factors such as material testing,mixture quality,construction quality and final quality inspection.The research proves that micro-surfacing construction technology is of superiority in road-maintaining.