汽车操纵稳定性研究的发展与展望

详细阐述了汽车操纵稳定性研究的发展历史,介绍了汽车操纵稳定性研究发展过程中诸如汽车数学模型的建立、轮胎模型的建立、驾驶员模型的建立、评价指标的提出等问题的研究历史与现状,以及操纵逆动力学在操纵稳定性研究中的发展历史,综述了虚拟仿真在汽车操纵稳定性研究中的应用历史,最后提出了操纵稳定性研究要解决的一些问题。     

液压式离合器操纵机构在AMT车辆中的控制研究

离合器的操纵机构是机械式自动变速器(AMT)的重要组成部分,其特点直接决定了离合器的控制策略。按照分离离合器所需的操纵能源,离合器操纵机构有人力式和气压式,其中液压操纵机构是人力式中的一种。与气压助力式离合器操纵机构相比,液压操纵机构具有摩擦阻力小、质量小、接合柔和等优点。该文研究了液压式操纵机构在AMT车辆上的控制特点,并基于试验结果,分析了其对AMT车辆性能的影响。     

基于重卡变速操纵机构综合性能的试验系统研究

根据重卡变速操纵机构性能要求,研制变速操纵机构综合性能试验系统,将机电技术、电液伺服技术相结合,模拟换挡操纵机构拉索实际负载,实现了拉索在运动过程中换挡操纵机构的选换挡间隙、机械效率、工作可靠性等的自动精准测量,本系统测试精度高,具有完善的人机对话功能、数据查询等优点,可为变速操纵机构测试提供可靠的试验方法,并对变速操纵机构的改进设计提供科学的参考依据。     

变速装置中的一种新型操纵机构

传统的端面凸轮预选操纵机构、孔盘越级变速操纵机构和液压预选操纵机构,都采用拔叉类结构滑移齿轮在花键轴上滑动来达到变速目的,这样使操纵机构繁杂,故障环节较多。现介绍变速装置中的一种新型操纵机构:     

玉米收获机安全操作要领

1启动（1）启动前准备。启动前应认真检查,确认发动机连接正常、油门操纵灵活,并按规定加足冷却液,检查机油是否在正常范围内、各部分接头是否旋紧及有无渗漏现象。将换挡操纵手柄、手制动手柄、五路阀操纵的发动机动力输出操纵手柄及茎秆还田机操纵手柄等均置于空挡位置,扳动熄火拉线,使喷油泵处于供油状态,最后将油门操纵手柄放在中间位置,插入钥匙点火启动。     

汽车最速操纵的客观评价指标研究

为了对最速操纵的汽车进行操纵稳定性评价,在考虑驾驶员忙碌程度、侧翻、侧滑评价指标的基础上,增加行驶速度单项评价指标、附着性能单项评价指标,提出了汽车最速操纵的综合评价指标;基于ADAMS/Car,对汽车进行双移线仿真试验,获得了汽车最速操纵的综合评价指标和单项评价指标仿真结果,比较了不同初始车速下汽车最速操纵的综合评价指标数值。结果表明,单项评价指标和综合评价指标都随时间延长而增大,当初始车速提高时,最速操纵稳定性综合评价指标增大,操纵稳定性变差。     

汽车操纵逆动力学的现状与发展

在回顾汽车操纵动力学发展历史的基础上，阐述了研究汽车操纵逆动力学的重要性，列举了三类汽车操纵动力学研究方法。描述了汽车操纵逆动力学的内涵，并给出了主要的研究方法和一些应用实例。最后，根据汽车操纵动力学发展史预测，汽车操纵逆动力学的发展有可能会导致汽车操纵动力学性能的显著提高，并解决现今流行的汽车操纵动力学中的“瓶颈”问题。     

客车驾驶员主要操纵人机解析

汽车设计人机工程随着汽车工业发展,越来越受到人们重视,对人机工程提出的要求也越来越高,人机工程涵盖范围也越来越广。重点针对客车驾驶员正常行驶主要操纵过程涉及部件人机工程设计做简单解析,主要包含转向操纵、组合开关操纵、踏板操纵几个模块内容。     

路面铣刨机电阻式自复位双手柄行走操纵装置

<正>大型路面铣刨机车身庞大,操纵台宽度可达到2m以上,操作手在铣刨机作业或行走时需在操纵台两侧巡回观察情况,为此在操纵台两侧各设置1个行走手柄,以满足操纵需要。传统铣刨机通常采用机械连杆式电控双手柄行走操纵装置,即2个操纵手柄被连杆连接在一起,拨动其中1个操纵手柄,另1个手柄联动。这种手柄操纵起来比较沉重、舒适性较差,不能满足施工需要。本文介绍1种无机械连接、操纵轻松自如的电阻式自复位双手柄行走操纵装置。     

汽车起重机离合操纵系统故障的解析与排除

汽车起重机多采用重载荷、大扭矩变速箱,这就要求起重机配置的离合操纵系统能够传递较大扭矩,单凭人力进行操作变得相对困难。所以汽车起重机底盘离合操纵系统主要采用气助力式液压离合器操纵机构,其操纵轻巧、反应灵便,但离合器操纵系统也是车辆故障多发部位,如离合器踏板发软、离合器分离不彻底等故障。因此离合操纵系统的可靠性对起重机的性能及使用寿命有极大影响。文中主要对气助力式液压离合器操纵系统的构成及原理进行解析,结合实际案例,给出了该系统的常见故障,并从结构及原理上进行分析与排除,提高诊断的正确率及故障排除效率。     

[学科发展]润滑研究进展

过去20余年，薄膜润滑、纳米润滑、极端工况摩擦与润滑、生物润滑、绿色润滑、微量润滑等取得了重要进展。最近10余年，超滑、仿生润滑、智能润滑与监测，以及摩擦学测试技术和模拟仿真技术等研究飞速发展。微观研究已经成为润滑研究的主要手段，面向风力发电机、高铁、深空探测、深海探测、大飞机、超高速飞行器、新能源汽车等领域的润滑与密封和绿色近零排放润滑研究已经成为工业界关注的焦点。超滑作为润滑领域的新型颠覆性技术，逐步显示出其在工业生产和人类日常生活中的应用优势与勃勃发展生机。生物润滑包括人类器官中的摩擦与润滑和仿生学研究，在人类健康生活方面展示出重要作用。极端环境（高温、超低温、真空、高压等）摩擦与润滑，在卫星、火箭、舰艇、核电站及其他国防设施上用途广泛。而智能润滑等新兴领域发展，也将智能化应用到润滑领域，为设备的智能运行和制造提供了新的思路。在此，对润滑领域几个重要发展方向，如超滑、薄膜润滑、纳米润滑、极端工况摩擦与润滑、智能润滑、生物仿生学、绿色摩擦与润滑，以及摩擦学测试方法等方面进行回顾，介绍了国内外同行最新研究进展，并对未来进行了展望。     

Challenges and Opportunities of AI-Enabled Monitoring,Diagnosis&Prognosis:A Review

Prognostics and Health Management(PHM),including monitoring,diagnosis,prognosis,and health management,occupies an increasingly important position in reducing costly breakdowns and avoiding catastrophic accidents in modern industry.With the development of artificial intelligence(AI),especially deep learning(DL)approaches,the application of AI-enabled methods to monitor,diagnose and predict potential equipment malfunctions has gone through tremendous progress with verified success in both academia and industry.However,there is still a gap to cover monitoring,diagnosis,and prognosis based on AI-enabled methods,simultaneously,and the importance of an open source community,including open source datasets and codes,has not been fully emphasized.To fill this gap,this paper provides a systematic overview of the current development,common technologies,open source datasets,codes,and challenges of AI-enabled PHM methods from three aspects of monitoring,diagnosis,and prognosis.     

振动子结构综合与修正方法研究综述

在大型复杂的结构设计过程中,子结构综合与修正方法由于其快速、动态、综合等特点越来越广泛地应用于现代结构设计之中,以完善子结构综合与修正方法知识参考、引起国内学者关注该技术研究为目的,阐述了振动子结构与系统之间的综合与修正方法。在子结构综合方法中,主要对比分析了模态缩减与综合、频域JETMUNDSEN、REN、机械阻抗导纳法综合法、频响函数奇异值分解降噪法、子系统转角自由度刚柔等效及转换方法的原理及应用,评述了上述方法的优点与不足,就尚未解决的问题作了进一步探讨;在子结构修正方法中,对比分析了多重参考基准修正法、目标函数动态修正法、参数型修正、神经网络型修正、灵敏度修正、频响函数修正等方法的应用,总结了模型修正方法中存在的一些问题。最后,提出了振动子结构综合及修正方法的研究趋势。     

基于Java EE的农田实验数据的自动采集与管理

为实时准确获取农田信息,提高农田实验数据的自动采集与管理水平,实现节水灌溉,该文综合农学、统计学、物联网技术和生态学等的基本理论与方法,以3S(CIS,RS,GPS)技术为核心,基于遥感技术的宏观性、GPS精准定位的特点以及地理信息系统的空间性,结合无线通信、Web等相关集成技术,借助专家决策系统的生产和管理决策,针对某农田测坑试验场开发了一款具有自主知识产权的农田测坑试验数据(空气温度、湿度和光照度、土壤含水量等)自动化采集与管理软件系统,可现场检测设备远程操作,并具有数据采集、输入和输出、查询、统计、分析等功能。     

Chemical and Mechanical Characteristics of a Deep-Dewaxed Mineral Oil Hydraulic Fluid

This paper is a reasonably complete presentation of the formulation, the physical and chemical properties, and the pump loop behavior of a deep-dewaxed mineral oil, MLO 60–294. Properties given include: (a) viscosity and bulk modulus as functions of both temperature and pressure, (b) specific heat, density, thermal expansion, vapor pressure, and thermal conductivity as functions of temperature, and (c) pour, cloud, flash, and fire points. The behavior of this fluid in one pump loop to 700 F, and in a second loop to 600 F, is discussed. Excellent fluid performance was obtained in these pump loops at 400, 500, 550, and 600 F; however, the fluid degraded rapidly at 700 F.     

Mice embryology: A microscopic overview

In this work, we studied the embryology of mice of 12, 14, and 18 days of gestation by gross observation, light microscopy, and scanning electron microscopy. Grossly, the embryos of 12 days were observed in C‐shaped region of the brain, eye pigmentation of the retina, first, second, and third pharyngeal arches gill pit nasal region on the fourth ventricle brain, cervical curvature, heart, liver, limb bud thoracic, spinal cord, tail, umbilical cord, and place of the mesonephric ridge. Microscopically, the liver, cardiovascular system and spinal cord were observed. In the embryo of 14 days, we observed structures that make up the liver and heart. At 18 days of gestation fetuses, it was noted the presence of eyes, mouth, and nose in the cephalic region, chest and pelvic region with the presence of well‐developed limbs, umbilical cord, and placenta. Scanning electron microscopy in 18 days of gestation fetuses evidenced head, eyes closed eyelids, nose, vibrissae, forelimb, heart, lung, kidney, liver, small bowel, diaphragm, and part of the spine. The results obtained in this work describe the internal and external morphology of mice, provided by an integration of techniques and review of the morphological knowledge of the embryonic development of this species, as this animal is of great importance to scientific studies. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.     

Analytical dynamics of mechanisms—a computer oriented overview

General-purpose computer programs such as IMP, DRAM, MEDUSA and DYMAC, for the solution of inertia-variant (linkage-type) mechanisms are beginning to emerge. These programs, which automatically generate, and numerically integrate, the equations of motions, are based upon different but related analytical and numerical principles. There has also been much recent discussion of “influence coefficient” methods, energy methods and related matters. This paper reviews the various principles and techniques available for formulating the equations of motion, for integrating them numerically, and for solving the associated kinetostatic problem for the determination of bearing reactions. The relative advantages of vector methods, d'Alembert's Principle, Lagrange's Equations with and without multipliers, Hamilton's Equations, Virtual work, and energy methods are discussed. Particular emphasis is placed on how well-suited the various methods are to the automatic generation of the equations of motion, and to the form and order of the systems of differential equations they lead to. It is shown how velocity ratios, influence coefficients, centripetal coefficients, generalized inertia coefficients, and Christoffel symbols interrelate the various methods, and tie them to classical results of Analytical Dynamics such as the “explicit” equations of motion and the power-balance principle. Methods for solving both the general dynamics problem, and the kinetostatic problem, are reviewed, and the particular methods of implementation used in the recently developed general-purpose computer programs, and in other recent literature, are described.     

A SEM study of the antenna and mouthparts of Omosita colon (Linnaeus) (Coleoptera: Nitidulidae)

There are direct relationships between the behavioral mechanisms and sensilla. To obtain a better understanding of the behavioral mechanisms in Omosita colon (Linnaeus) (Coleoptera: Nitidulidae), we investigated the types, quantities, and distribution of sensilla on the antenna and mouthparts of O. colon by scanning electron microscopy. The clavate antenna comprised the scape, pedicel, and nine segment flagellomeres and had six types of sensilla, including two subtypes of sensilla chaetica (SC), three subtypes of sensilla basiconica (SB) and sensilla trichodea (ST), and one type of sensilla cavity, sensilla styloconica, and Böhm bristles (BB). The chewing mouthparts of O. colon consist of the labrum, mandible, maxillae, labium, and hypopharynx and had seven types sensilla, including two subtypes of SC and sensilla placodea, seven subtypes of SB, and one type of BB, ST, sensilla coeloconica, and sensilla campaniformia. In this research, we also deduced the relationships between the sensilla on the antenna and mouthparts and their functions.     

光栅平动式光调制器光学特性分析

提出了一种基于微光机电系统的可用于投影显示及相关器件的新型光栅光调制器,介绍了其结构、工作原理和加工流程.对器件进行光学分析,优化和仿真,得出器件结构参数与光学特性之间关系.器件的可动光栅占空比e=0.5,光栅常数d=6 μm,长度L=39 μm,宽度w=36 μm,边距w0=1.5 μm时,理论上±1级衍射效率η=37.0%,对比度V=625;可动光栅与下电极在开态和关态时间距分别为0.65 μm和0.78 μm,器件单像素尺寸为51 μm×51 μm.     

制造信息化的分析与研究

论述了制造信息化的内涵、现状、存在的问题和对我国制造业的影响，认为制造信息化主要是指产品设计、制造及底层设备的信息化，隶属于制造业信息化范畴，进而提出制造信息化应该与管理、决策信息化等协调发展，才能推进制造业信息化。并且描述了一个建立在制造信息化基础上的未来智能工作场模型，其具有软硬件方面的快速可重构性，以知识的挖掘、应用、革新作为驱动制造、装备智能化和高效率工作的内在机制，能形成多个车间、工作场间信息的双向流通。