Analysis on quantifiable and controllable assembly technology for aeronautical thin-walled structures

Assembly affects the product's performance and reliability directly. The current assembly method based on geometric deviation quantity controlling, cannot guarantee the physical performance for complex aeronautical thin-walled structures effectively, such as assembly geometry accuracy and internal interactive stress. And assembly performance controlling is taken as the bottleneck problem that restricting the new aviation requirement of sub-millimeter assembly. In this paper, by proposing the accurate prediction and process-oriented adjustment&controlling strategies on assembly quality, construction on working mode with “quantifiable and controllable” characteristic was proposed, whose aim was to reduce the phenomenon of out-of-tolerance and deformation rebound error, and the ultimate goal is to reduce the uncertainty of assembly performance parameters. At the technical level, the academic development context and existing problems for assembling thin-walled structures were reviewed and analyzed, such as assembly process parameters optimization, assembly error transfer and accumulation, comprehensive adjustment on assembly quality, and virtual assembly simulation validation. Then the key future research trends for aeronautical structure assembly were also put forward, i.e. the force/deformation coordination among multi-type finite units for non-ideal assemblies, the dynamic construction of stiffness matrix for intermediate assemblies considering geometric nonlinearity, the adaptive balance on assembly performance driven by physical modeling and measured data, and the inverse optimization on assembly quality and parameters with intelligent data processing. This paper would lay a solid foundation for achieving the accurate assembly mode with the characteristics of “intelligent/scientific, and active/collaborative controlling on geometric shape and physical performance”, and higher assembly quality and efficiency could also be gained.     

Assembly language design and development for reconfigurable flexible assembly line

To improve the efficiency and controllability of our previous proposed cross-category product assembly line, we design an assembly language (A-code) to express a product's assembly process. We further develop an IDE to describe assembly processes as statements, which are organized according to predefined syntax as an A-code file. The interpreter translates statements into executable low-level commands. In addition, a four-layer architecture of the A-code assembly system (ACAS) is proposed to implement this language, thus an A-code files can be run on the assembly line physically. The proposed ACAS can reconfigure each unit for specific products, and control their assembly processes. The expressivity of this language is validated in two assembly cases, a simple shuttle valve and a complex relief valve. The functionality and feasibility of this system are tested by assembling 50 relief valves. The results demonstrate our ACAS can perform complex assembly tasks in a more efficient way.     

The state of the art of testing standards for integrated robotic systems

Technology standards facilitate the transparency in market and the supplies of products with good quality. For manufacturers, standards make it possible to reduce the costs by mass production, and enhance system adaptabilities through integrating system modules with the standardized interfaces. However, International standards on industrial robots such as ISO-9283 were developed in 1998, and they have not updated since then. Due to every-increasing applications of robots in complex systems, there is an emerging need to advance existing standards on robots for a broader scope of system components and system integration. This paper gives an introduction of the endeavors by National Institute of Standards and Technology (NIST); especially, it overviews the recent progresses on the standardized tests of robotic systems and components. The presented work aims to identify the limitations of existing industrial standards and clarify the trend of technology standardizations for industrial robotic systems.     

传统文化在现代设计中的基因裂变

我国对传统文化的探索和研究一直处于稳步攀升的阶段,随着社会的发展及科学水平的提高,越来越多优秀的传统文化出现在大众的视线中。看似遥远的传统文化也开始逐渐渗透到人们的工作生活当中,而传统文化的发展维度并不局限于此。文明的进步,信息的高速互通打开了人们认知的新世界,提高了精神层次的追求。为此,现代设计当中不乏具有传统文化元素的设计作品。但是,这类设计中的部分作品仅有其表,不具其里,往往无法将传统文化的精髓表现出来,生搬硬套的应用方式,使人们出现了审美疲态。基于此,笔者试图以传统文化为切入点,以现代设计为载体,追本溯源,分析传统文化的传承基因,并建立起两者之间的联系。探寻传统文化基因在现代设计中的裂变新范式,明确其设计趋势。     

改进TS算法的助航灯光站人员管理优化方法

为了解决助航灯光站在人员管理方面存在的对灯光设备损伤情况的确认与修复能力低下以及修复情况反馈不及时等问题,提出了一种改进禁忌搜索方法。此方法以禁忌搜索为基础,并且引入了惩罚权重以及多领域分析组合的方法进行优化提高,其中权重可根据具体情况进行动态调整。通过已知资料进行建模,并且设置了多种可能存在的排班情况,以扩大样本空间。通过实例分析,得到在最符合实际的情况下,本文研究方法的加权有效效率值为82.23%,相比于整体规划法的74.69%以及变领域禁忌算法的77.27%分别提高了7.54%和4.96%。本文的研究对提高助航灯光站人员管理有一定的借鉴意义。     

基于PLC控制的自动化生产线的产能自调节系统研究

自动生产线上输送带的速度与生产计划以及系统废品率之间无法互相调节,导致了生产效率低、废品率高等现象。为了提高自动分拣生产线的产能,本文设计了产能自调节系统;叙述了构建系统的研究思路;搭建了系统的模型;分析了系统控制方案的工作原理以及影响产能的主要因素;确定了系统的主要技术指标;构建了特定的控制算法模型;运用PLC、步进电机、变频器以及工业APP软件对产能自调节系统进行了生产计划管理、系统状态实时监控、系统运行控制等功能的实现;搭建了工业以太网和PROFIBUS-DP复合型通信网络,并在工业网络实训台上完成了系统的试验研究,根据试验结果对整个系统做了优化调整。     

基于设计思维的矫正产品设计与创新

文章对现代青少年使用矫正产品的用户体验进行设计与创新,提出青少年使用矫正产品时拥有的心理负担,将审美与实用相结合的设计,满足用户的需求,为其带来良好的身心体验。提升青少年产品用户体验的需求十分迫切,文章从用户心理需求出发,探讨青少年近视矫正产品的设计策略,设计符合其生理及心理特征的近视矫正产品。     

时效温度对GH2132合金组织与力学性能的影响

采用光学显微镜、扫描电镜、微机控制电子万能试验机等仪器研究了620、650、680、720、750、780 ℃单级时效和720 ℃+650 ℃双级时效对GH2132合金显微组织及力学性能的影响。结果表明:双级时效的抗拉强度和剪切强度高于单级时效的抗拉强度和剪切强度,抗拉强度达到1130 MPa,剪切强度达到720 MPa。且在620~780 ℃的温度范围内进行单级时效时,随着时效温度的提高,合金的抗拉强度和剪切强度呈现先升高后降低的趋势,在720 ℃时抗拉强度达到最大值1065 MPa,剪切强度达到最大值685 MPa。     

基于平稳小波与BP神经网络的换相失败检测算法

针对高压直流输电系统中换相失败检测问题,提出了一种采用平稳小波分析和BP神经网络的换相失败检测算法.通过平稳小波提取换相失败信号不同尺度的小波能量,作为特征向量输入神经网络中进行训练,并得到能够进行自动化识别的分类模型.在实际采集得到的200组数据集上进行了算法验证,结果表明,文中算法可以有效地区分直流输电系统中的换相失败和正常信号,其平均检测精确度达到95%以上,为进一步系统准确无功补偿提供保障.     

Analysis and research on the processing threshold of femtosecond laser

1.194 2×1014 W/m2. This work is helpful to further analyze the applications of fs laser processing. It provides guidance and reference for different kinds of fs laser processing methods.