贵州汽车维修服务案例：高端车型精准检修与性能优化实战

硫化促进剂太赫兹光谱数据扩充策略与定量检测

为实现橡胶制品中硫化促进剂含量的快速,无损,精准检测,本研究采用太赫兹时域光谱技术,结合数据扩充与化学计量学方法,对多组分橡胶混合物中硫化促进剂进行定量分析.针对橡胶混合物光谱重叠严重,样本量偏小易导致模型过拟合,泛化能力差等问题,提出基于数据融合与最小二乘高斯拟合法(LSGF)的数据扩充策略,并构建遗传算法优化支持向量回归(GASVR)定量模型.为降低数据维度,提升建模效率,采用变量空间迭代收缩算法(VISSA)对原始及扩充后光谱进行特征提取.结果表明:数据扩充可显著提升模型预测性能,其中LSGF方法效果最优;经VISSA特征提取后,模型精度进一步提升,LSGF扩充数据在预测集上的相关系数Rp高达0.982 6,RMSEP低至0.002 3.该方法可为橡胶配方优化与行业绿色可持续发展提供技术参考.

基于变量喷雾的果园自动仿形喷雾机的设计与试验

为提高果园喷雾机自动化与精准喷雾作业性能,设计了一种基于变风量与变喷雾量的果园自动仿形喷雾机,喷雾系统以冠层分割模型作为变量处方,采用扫描精度高的激光传感器作为探测源,以电磁阀和无刷直流风机为执行元件,通过探测果树冠层体积调节电机和电磁阀的脉宽调制(pulse width modulation,PWM)信号以实时调节风机转速和喷头流量.设计了可独立调节风量和喷雾量的雾化单元,通过各个独立风机产生的高速气流协助雾滴穿透冠层;喷雾机最大作业高度4.2m.田间试验结果表明,在行株距为5 m×2 m的单株苹果树左右两侧平均沉积量分别为1.92和1.37 uL/cm2,最少雾滴数为46.2个/cm2,大于常用方法对风送喷雾中雾滴喷幅界定的20个/cm2;树冠轮廓与沉积量和风速变化拟合结果显示,设计的喷雾机能够根据树冠信息实现仿形变量施药.该研究为果树病虫害防治提供新方法与新装备,为精准植保机具的结构设计和性能优化提供理论与方法参考.%In order to improve the automatic working performance of orchard sprayer,in this study,an automatically variable-rate orchard sprayer with 40 nozzles and 8 fans based on LIDAR (Light Detection and Ranging) was developed.The high-precision scanning laser sensor was adopted as the detecting source to detecting the canopy parameter.Electromagnetic valve and brushless fan were adopted as actuators to control the flow rate and air volume based on the pulse width modulation (PWM) signals.Each nozzle in the spray system,coupled with a solenoid,achieved variable rate delivery in real time based on the canopy volume.Each side of the prototype equipped four integrated atomization units with one independent brushless fan.The independent brushless fan located behind of atomization unit,and assisted the droplets sprayed from the five nozzles blowing into the canopy,which is conductive to the local regulation of spraying quantity.The brushless motor has the advantages of fast-response,high-speed,and long working-time.The rotating speed of each brushless motor could be adjusted in real-time by PWM signal according to the canopy parameters of fruit tree.The canopy segmentation model was designed to measure the volume and density of canopy,which could meet 3 m height canopy.The canopy was divided into many canopy units,and each nozzle corresponded with one canopy unit and each brushless fan corresponded with five canopy units.A laptop was used to calculate the volume and density of each canopy unit based on the data scanned by laser sensor and the segmentation model.Then the spraying quantity needed forcanopy unit and the air volume needed for five canopy units were acquired by control system.Next,the PWM signals emitted by single chip microcomputer would be transmitted to the drivers of valves and fans to adjust the flow rate and air flow.A total of 48 channel PWM signals were designed for the whole machine,and each channel would be controlled separately.The gasoline generator was adopted as energy source to realize long-working and fully automatic spraying,and the independent brushless fan was used instead of central fan with PTO (Power Take Off)-power to realize partly air volume and use-dosage according to canopy size.The field experiments were conducted in an apple orchard,a research farm belonging to the China Agricultural University,in Beijing.The main tests included the test of deposition distribution in the canopy and air velocity distribution of different height.The tree row space was 5m×2m,the average height of tree was 4.1 m,and the canopy diameter was 2.6m.The environment temperature was 14℃,the humidity was 50.3% and the wind speed was 0.7-1.2 m/s.Tartrazine (2.5%o) was chosen as the tracer material and travelspeed was 0.8m/s.Water sensitive paper(2.6 cm×7.5 cm) and metallic screen mesh(2.5 cm×7.5 cm) were adopted to receive the deposition for the test of deposition distribution in the canopy.The artificial targets were arranged in the canopy in eight layers with three directions of right,left and middle in each layer.Also,a metal rod was established at the distance of 1.5m from tree center to fix the anemometers.The lowest anemometer was 1.2 m from the ground and the distance of adjacent anemometer was 0.4m.The results showed that the deposits on the from and back of tree were 1.92 and 1.37 μL/cm2,and the minimum number of droplets was 46.2per cm2,which was greater than the requirement of droplet adhesion rate over 25/cm2 in the application of pest and disease control.The coefficient variation of three depths of tree was 14.2%,18.0% and 13.7%,respectively.The fitting results of canopy contour with deposition and

基于TA3G原材料的金属接骨板化学成分与金相的产品质量评估

目的 系统探究 TA3G 纯钛原材料的化学成分与金相组织特征,揭示其与金属接骨板力学性能,生物相容性及临床应用安全性的关联机制.方法 随机选取 2020 年 1 月 —2024 年 12 月来自不同企业的 TA3G 接骨板样本 39 例,采用 ICP-MS 法检测化学成分,OM 法分析金相组织特征,参照 GB/T 13810-2017 标准评估质量一致性,通过统计学方法分析元素含量波动规律及与金相指标的相关性.结果 TA3G 以 Ti 为基体,平均含量达 99.49%±0.06%,所有样本 Ti 含量均≥99.0%;16 种检测元素均符合国标要求;元素稳定性差异显著,H,C,Ni 变异系数≥80%(稳定性低),Fe,O 变异系数 < 20%(稳定性高);金相指标呈正态分布(均值 7.61±0.55),均为典型 α-Ti 单相结构,O 元素含量与金相指标呈显著正相关(P<0.05).结论 精准控制化学成分与优化金相组织是保障 TA3G 接骨板性能与安全性的核心,可为产品选用,工艺升级提供参考,兼具工程价值与临床意义.

山东单县小麦播种机械自动化控制与性能优化实践探析

为推动精准农业在山东单县的应用,提升小麦播种作业的质量与效率,该文对当地播种机械的自动化控制与性能优化开展了实践探讨.通过系统分析传感,控制与执行等自动化关键技术,提出了从播种机结构,播种精度与作业速度三个维度的性能优化路径.结果显示,采用自动化控制与优化技术的高性能播种机,在播种均匀性,深度稳定性及漏播控制等关键质量指标上均有显著改善,并有效提升了作业效率,为实现小麦生产的节本增效与标准化管理提供了可靠的技术支持.

不确定视角下产品结构性能优化设计综述与展望

目的复杂产品在工程装备,航空航天等我国优先发展的战略领域中扮演着不可替代的重要角色,在其结构设计过程中普遍存在着各种不确定性,导致产品结构性能很难实现最优,甚至出现重大故障.方法针对复杂产品设计过程中的多粒度模糊不确定,随机不确定,不完备区间不确定和高维混合不确定等特点,将不确定性理论与产品结构设计过程相结合,系统地构建了不确定视角下产品结构性能优化设计理论体系,提出了多粒度模糊不确定下产品质量特性精准提取,随机不确定下产品功能结构模块化求解,不完备区间不确定下产品结构方案多属性决策,高维混合不确定下产品关键结构可靠性优化等关键技术,并指出了产品结构性能优化设计的未来发展方向.结论此设计理论能够充分适应和利用产品设计过程的多种不确定信息,为在结构设计环节切实提升产品性能提供了有力参考.

结合Vehicle Spy的整车爬坡性能主观评价方法

整车性能评价常用方法有:主观评价,客观测试,仿真分析.主观评价是一种传统而又非常有效的整车性能匹配与调校方法,而客观测试与仿真分析的方法能够获得驾驶员借由主观判断无法察觉的系统信息,这使得对整车性能的优化变得简单易行.在目前汽车爬坡能力主观评价中,需要结合对汽车的爬坡性能的客观测试,以辅助主观评价工程师的评价工作,并使评价结果为整车标定方向做更精准的指引.文章提出了一种结合 Vehicle Spy 的整车爬坡性能主观评价方法.

3D四轮定位仪检定装置及其优化设计

随着我国经济的发展和人民生活水平的提高,我国汽车拥有量逐年增加,人们开始将目光投向汽车安全,四轮定位作为汽车安全行驶性能的重要指标,受到交通管理部门,技术监督部门,车企,驾驶员和汽车维修保养行业的重视.车轮定位参数在汽车出厂时应该经过严格检测,保证车辆行驶安全.车辆在行驶一段时间后,可能出现汽车行驶不稳定,轮胎异常磨损,方向盘操作吃力等现象,这都与车轮的定位参数有关. 四轮定位的主要参数包括:前束角,外倾角,主销内倾角,主销后倾角,推力角.定位参数要靠四轮定位仪来检测校正,才能保证汽车的行驶安全.当下正在广泛使用的四轮定位仪是3D四轮定位仪,它是由高分辨率的摄像机采集反光板上的图像信息,经过图像处理计算出车轮的定位参数.相对于传统的四轮定位仪,它使用一块反光板代替传统的装有复杂光电装置的传感器,使得新型四轮定位仪装夹方便,操作简单,检测迅速而且精度高. 3D四轮定位仪具有检测方便,占用地面面积小等诸多优点,但是还没有一种精准的方式对它的各项技术指标进行全面衡量.针对这种情况,本文开发了一种图像式四轮定位仪的检定装置,该装置具有检测稳定性高,检测精度完全能够达到图像式四轮定位仪检定所需的精度,真实模拟汽车四轮定位各主要定位参数,满足各计量单位,相关科研单位,国家相关权威检测部门,大中型企业和相关院校对这种四轮定位仪的检定校准需要. 本文主要探讨了3D四轮定位仪的检定原理和方法,研究检定装置的机械结构及其优化,应用ANSYS软件对检定装置重要部件做有限元分析,在此基础上优化机构设计,以节省材料,减轻质量,改进结构的可操作性并使装置更加方便携带为目标,寻求一种最优的结构设计.建立在严格缜密精确模拟计算基础上的工程设计,在结构刚度,检测精度上取得合理的分析结果,进一步的优化设计使结构设计更加合理.文章最后研究了三维设计软件Solid Works与有限元分析软件ANSYS相结合的问题,指出两者兼容容易出现错误的地方,表明CAD和CAM相结合将是未来工程设计的一个发展方向. 3D四轮定位仪检定装置是一个复杂的系统问题,本文所做研究注重结构设计与分析,更多的细节问题还需要进一步深入研究.