惯性约束聚变束靶耦合的监测及精度分析

为了提高惯性约束聚变实验中高功率激光驱动装置束靶耦合的精度,介绍了几种束靶耦合监测方法,包括靶室外直接监测,靶室内直接监测,靶室内基于共轭原理的传感器监测等.分析了各种方法的优缺点,并重点对基于光学共轭原理的传感器的耦合精度进行了研究,分析了图像测量误差,C保护玻璃引入的误差,调焦导轨运动时引入的误差及传感器标定装校时引入的误差.实验测试及精度分析表明,共轭式传感器引入的束靶耦合误差为±10 μm.采用这种基于光学共轭原理的传感器,可以实现大型激光驱动装置的快速、高精度束靶耦合.     

惯性约束聚变靶丸高精度X射线数字成像

为了实现惯性约束聚变(ICF)靶丸几何尺寸的高精度、高效率检测,开展了靶丸X射线数字化成像系统的设计与研制。首先,分析了X射线直接投影成像和X射线透镜耦合显微成像的适用范围,根据ICF靶丸尺寸小、吸收衬度弱的特点,确定了基于X射线透镜耦合显微成像的技术路线。然后,分析了影响系统成像分辨率、图像衬度和测量效率的关键因素,确定了低几何放大成像,低电压、小焦点、高功率X射线源及高分辨CCD探测的总体技术方案,该方案能够有效抑制相衬效应和半影误差,解决了现有X射线数字成像设备测量靶丸时边缘扩展严重、尺寸测量误差大的问题。最后,对系统的性能进行了分析测试,实验结果表明,系统成像衬度良好,成像效率较高,分辨率优于0.5μm。靶丸几何尺寸的测量不确定度可达0.9μm(k=2),满足ICF靶丸几何尺寸高精度、高效率的检测需求。     

惯性约束聚变激光驱动装置用光学元器件的研究进展

介绍了为提高惯性约束聚变(ICF)激光驱动装置的光束质量和输出功率,我国在神光系列激光装置的建设、运行和性能提升方面开展的工作。综述了我国近年来ICF激光装置用光学元器件的重要研究进展。文中涉及了高纯金属铪和磷酸二氢钾(KDP)等原材料的制备和四大主材(钕玻璃、高纯度KDP、熔石英和KDP/高掺氘KDP(KDP/DKDP晶体)的熔炼、加工和生长。描述了元器件的冷加工(针对钕玻璃、白玻璃、KDP晶体)技术和镀膜技术(针对介质膜和化学膜)。最后,给出了针对大口径光学元件工序检及终检开展的多项关键检测技术。文中介绍的关键技术与工艺满足了绝大部分光学元器件的需求,显著提升了光学元器件的研发和生产能力。     

基于图像拼接的惯性约束聚变终端光学元件在线检测

针对惯性约束聚变(ICF)终端光学元件的高精度在线检测,提出了一种基于图像拼接的检测方法。该方法主要包含图像配准及图像融合两个部分。在图像配准部分,采用基于局部损伤点特征匹配的方法来解决在线检测图像中信息过少,以及子图像间存在曝光差异的问题,并将检测系统的运动信息应用到配准过程中,提高了检测精度及效率。在图像融合部分,采用泊松融合的方法来消除曝光不均匀所产生的"拼接线",实现了检测图像的"无缝拼接"。用本文算法与尺度不变特征变换(SIFT)算法对ICF终端光学元件在线检测(Final Optics Online Inspection,FOOI)图像进行了实验对比,结果表明,本文提出的图像配准方法优于SIFT算法。通过4×4方式得到的拼接图像显示,本文方法可以大幅度提高ICF系统中FOOI装置的检测分辨率。     

用于惯性约束聚变靶丸测量的激光差动共焦传感器

针对目前原子力显微镜等方法只能测量激光惯性约束核聚变(ICF)靶丸外表面等难题,研制了高精度、非接触、小型化的激光差动共焦传感器(LDCS).该传感器基于差动共焦原理,利用激光差动共焦轴向响应曲线的零点对靶丸内外表面和球心分别进行定位,并结合物镜微位移驱动技术,实现靶丸内外表面和壳层厚度的高精度测量.该方法减少了靶丸表面的反射率、倾斜等因素对测量瞄准特性的影响,显著提高了系统的抗干扰能力.将传统的显微成像与差动共焦测量光路进行有机融合,实现了对被测样品的精确瞄准.初步实验与理论分析表明:当测量物镜的数值孔径NA为0.65时,LDCS的轴向分辨力优于5 nm,信噪比优于1 160,过零点的标准偏差为10 nm.该传感器为激光惯性约束核聚变靶丸测量提供了一种新的技术途径.     

激光原型装置X光针孔相机总体结构设计与分析

针孔相机是惯性约束核聚变(简称惯性约束聚变)中用于激光加热靶成像的重要光机器件。根据激光原型装置对针孔相机的要求,采用CCD(Charge Coupled Device)作为成像系统,对针孔相机进行结构设计,并根据针孔相机真空度的时间要求,对放气孔的开口面积进行分析计算,采用拓扑优化技术对开口的分布进行优化分析,设计的针孔相机复位精度达到29μm,超过了30μm的设计要求,实际应用表明设计的针孔相机满足惯性约束聚变要求。     

惯性约束聚变装置真空靶室组件结构稳定性优化设计

真空靶室组件的结构稳定性对惯性约束聚变(ICF)装置的束靶耦合精度有重要影响,本文对真空靶室组件的结构稳定性进行优化设计。首先研究真空靶室组件的动态特性,求解其固有频率和振型;其次,分析支墩不同结构参数对真空靶室组件前三阶固有频率的影响,并由此建立结构参数影响固有频率的数学模型;最后,进行真空靶室组件的结构稳定性设计优化,求解真空靶室组件的最优结构。结果表明,优化后真空靶室组件的一阶固有频率为14.44Hz,满足ICF装置的设计要求。     

新型压电惯性哗啦结构设计与数学模型的建立

研究了一种压电惯性敏感器件的结构特点和工作机理,建立了该敏感器件的动力学模型。     

惯性释放在升降平台结构设计中的应用

基于惯性释放理论,对某型舰载升降机升降平台的强度和刚度进行有限元计算。与传统计算方法相比,惯性释放法能有效避免边界条件对结构力传递路径的影响,更加精确地反映结构的真实应力情况。根据钢丝绳升降平台的结构和载荷特点,结合有限元理论,对升降平台的刚度、强度进行分析计算。计算结果表明,采用惯性释放法对升降平台进行计算可以消除约束点反力造成的应力集中,使结构的变形状况更加直观、真实。对升降平台的结构设计与改进提供更加合理的分析与评估。     

A comprehensive approach to facility layout design and cell formation

Group technology (GT) and a facility layout problem share a common factor to optimize, which is the “Intercell Flow or Material Handling Flow”. Most group technology-based approaches use binary part-machine incidence matrix for cell formation. Impacts of flow volume analysis between machine pairs have not been analyzed in the design of cellular manufacturing systems. It is important to analyze the placement of machine cells for reduced material handling costs at the grouping stage itself. This paper develops a method to integrate GT philosophy with a facility layout problem using “From–Between” relationship chart as a tool. A new optimization technique with a “from–to chart” as the primary input, is used to determine the cell formation. A modified grouping efficiency measure is used to determine the efficiency of grouping. A genetic algorithm-based approach is used for machine cell placement within a layout matrix. Cells formed using the proposed approach show reduced intercell flows, high grouping efficiencies and reduced material handling costs when cells are placed in a layout grid compared to existing cell formation approaches.     

Multiple-attribute decision-making approach for an energy-efficient facility layout design

Due to the trends of energy shortage and energy price rise, energy efficiency, which was always ignored over the past decades, becomes a worldwide hot issue and also a significant challenge for most factories. Therefore, it is necessary to incorporate energy-relevant criterion as a key criterion with traditional criteria in the layout planning phase. As a multiattribute decision-making (MADM) problem, the evaluation and selection of facility layout alternatives are often difficult and time consuming since the criteria generally have different units and conflicting features. In this article, a MADM approach which incorporates the advantages of rough set theory, analytic hierarchy process (AHP), and technique for order preference by similarity to ideal solution (TOPSIS) is proposed to solve the facility layout design problem with considering both traditional layout criteria and energy relevant criteria. At first, rough set theory is integrated with AHP to determine the weights for each criterion of alternatives. Then, TOPSIS is applied to get the final alternative ranking. Besides, sensitivity analysis for both decision weights and production rates is performed, and a comparison among different decision-making approaches for the same problem is also studied to demonstrate the rationality of the final decision. Finally, a practical expanding case is studied to validate the proposed approach.     

采用遗传算法的RMS设备布局设计及仿真

根据可重构制造系统车间设备布局的最小物流费用原则,建立车间的单行和多行设备布局的数学模型,针对设备布局属于NP完全问题,提出利用MATLAB遗传算法工具箱实现一个基本的设备布局模型的求解,降低了遗传算法对设备布局问题的求解难度。最后,给出一个六台设备的车间布局实例,采用Delmia/QUEST三维可视化仿真软件对求解的布局结果建立仿真模型,并进行仿真结果分析,为设备布局的改进提供决策依据。通过重建仿真模型,能够很好地解决设备布局问题。     

A population-based hybrid ant system for quadratic assignment formulations in facility layout design

The facility layout design problem is an extensively studied research problem and belongs to nonpolynomial hard (NP-hard) combinatorial optimization problem. Quadratic assignment problem (QAP) is one of the formulations that is investigated for facility layout design because of its wide applicability. Ant colony optimization (ACO), a biologically inspired heuristic has centered on solving the QAP by achieving approximation as good as possible. This paper presents a population-based hybrid ant system (PHAS), which is an extension of the hybrid ant system (HAS) in which the size of the ant colony has been fixed. The performance of the proposed ant algorithm for QAP is compared with the existing metaheuristic implementations such as tabu search, reactive tabu search, simulated annealing, genetic hybrid method, HAS, and max–min ant system. The experimental results show that the proposed PHAS perform significantly better than the other existing algorithms of QAP.     

Dynamic facility layout problem based on flexible bay structure and solving by genetic algorithm

Finding positions of departments on the plant floor for multiple periods while minimizing the sum of material handling and rearrangement costs is the base consideration of dynamic facility layout problems (DFLP). In this paper, a new kind of DFLP using flexible bay structure is studied. In a plant layout, based on flexible bay structure, departments are assigned to parallel bays in a plant floor. Departments could be free oriented and may have unequal areas as well as a mixed integer programming formulated to find optimal solutions. Due to complexity, only small-size problems could be solved in logical time while using exact methods. Therefore, a genetic algorithm (GA) was proposed to solve this optimization problem. This method was tested on some test problems of the DFLP literature. The results show the effectiveness of the proposed algorithm.     

基于模糊理论的混合布局设备单元划分

针对设备混合布局方案设计过程中忽略了设备单元划分的不足,运用模糊理论以设备间在某种特性上的模糊关系为依据进行设备单元划分,并通过置信水平λ的变化率找出最优的模糊聚类.以某日化企业面膜生产车间为例,详细阐述了如何利用模糊理论进行设备单元划分,对解决类似问题具有一定的借鉴作用.     

设施布局形式的拓扑结构研究

借鉴计算机网络的拓扑结构和制造系统的物料流动形式,确定制造系统的设施布局形式,并利用拓扑学中图形的拓扑性质,对设施布局形式进行修正,建立制造系统设施布局的创新拓扑结构形式:单行与双行总线型、网型、环型、星型与树型.     

复杂结构产品虚拟布局与装配设计系统研究

为了在设计阶段发现并解决复杂结构产品的布局和装配问题,针对复杂结构产品的特点,分析了复杂结构产品虚拟布局与装配设计系统的需求。以算法设计为基础进行布局方案设计,以虚拟装配设计为检验手段对布局结果的可装配性进行检验和评价。建立了系统设计过程的功能模型,阐述了复杂布局问题的求解算法、面向虚拟装配的产品建模技术和虚拟装配仿真技术等主要关键技术。在这些原理方法研究的基础上,以飞行器仪器舱为应用背景,进行了原型系统的开发,给出了部分运行实例。运行结果验证了系统原理及其实现技术的可行性和实用性。     

Augmented reality assisted facility layout digitization and planning

Journal of Mechanical Science and Technology - Facility layout planning (FLP) has an important role in manufacturing industries. There are few approaches to solve FLP such as procedural,...