基于LabVIEW的包装六面体跌落方位控制研究

对跌落方位的控制是跌落试验机自动控制技术的核心,目前大多采用人为固定跌落方位。为了降低操作复杂程度和人为误差等因素的影响,设计了一种基于虚拟仪器LabVIEW的包装六面体棱跌落的控制方案。方案采用梁式测力传感器将测得的信号通过数据采集卡传输到主机端,然后用LabVIEW软件对采集的数据进行实时显示、监测与控制。     

跌落冲击试验机的控制和数据采集处理系统

基于经典的缓冲材料缓冲特性理论,开发了一套跌落冲击试验机系统,并研究了自由跌落冲击过程中的数据采集与处理中的关键问题。通过采用多种数字滤波技术,有效地削弱了随机信号的干扰;利用一种新的获取初速的数据处理方法,使得数据更趋于实际值;通过获取的实验数据,利用最小二乘法进行包装材料缓冲特性的拟合,获得了缓冲材料的缓冲特性曲线。在相同条件下,针对EPE 材料进行了多次跌落冲击试验,实验结果符合经典的缓冲包装材料缓冲特性曲线,实验最大相对误差为3. 7272%。实验表明,试验系统数据采集规范、数据处理方法准确,并验证了试验系统的可靠性,为缓冲包装设计提供了有利的科学依据。     

基于单片机的包装六面体跌落方位控制算法

对跌落方位的控制是跌落试验机自动控制技术的核心.通过对包装六面体在垂直冲击跌落试验中不同跌落方位旋转过程的几何分析,提出了一种基于单片机的包装六面体跌落方位控制算法,该算法可根据设定自动完成任意跌落方位的形成.实际检验表明,控制算法所得结果与重力线检验一致,表明该算法正确,可用于包装六面体跌落试验跌落方位的控制.     

可降解餐具动态响应数值分析

目的分析植物纤维材料制成的可降解餐具容器抗冲击性能,建立其跌落动态有限元模型。方法利用万能试验机对植物纤维片材进行拉伸试验,得到其本构行为;建立餐具容器有限元模型,利用ABAQUS/Explict研究餐具容器在平、斜跌落2种冲击载荷下的破损规律。结果在平跌落情况下,底部出现了放射性的裂纹,这是由植物纤维断裂演化的应变较小导致;斜跌落相较于平跌落失效情况更严重。结论所得结果能为评估餐具容器的动态强度提供数据参考。     

苹果临界跌落高度和损伤脆值的试验研究

目的研究苹果的损伤率与临界损伤脆值的关系。方法利用自制摆锤冲击试验机设计多个高度的苹果跌落试验,分析苹果跌落冲击过程的损伤特性,得到临界跌落高度;在临界跌落高度以上的高度进行跌落试验,得到苹果在跌落过程中的加速度-时间曲线。结果结合试样在不同高度跌落所得的峰值加速度幅值,得到了试样的损伤脆值;根据不同跌落高度下的苹果的损伤体积,得到了苹果在不同损伤率下的损伤脆值。结论研究得到的损伤脆值与损伤率的关系对苹果缓冲包装的改进具有参考意义。     

运输包装试验计算机辅助测试系统的研究与开发

概述了对跌落试验机、垂直冲击试验机和振动台的计算机辅助测试系统的研究,提出了压力试验机计算机辅助测试系统方案,开发了基于VC 6.0的计算机辅助测试软件.     

单层与多层苹果跌落冲击损伤研究

跌落冲击是导致果品机械损伤的主要因素.利用MTS886跌落冲击试验机进行单个与多层苹果的跌落试验测定,分析跌落冲击试验机的冲击过程特性,提出了果品跌落吸收能量的计算公式,得到了苹果跌落损伤体积、速度变化量与其吸收能量之间的关系.结果表明:单个苹果的损伤体积与其吸收的能量之间成线性关系,苹果的速度变化量与损伤体积之间成二次项关系;多层苹果的总损伤体积与其吸收总能量存在线性关系,而其中的单个苹果与其吸收的能量之间不存在线性关系.     

高速摄影技术在跌落加速度测试中的应用研究

以垂直冲击试验机为测试平台,对采用高速摄影机测试跌落冲击加速度的方法进行了初步研究;通过将分析结果与加速度传感器测试值进行对比,分析了高速摄影机测试精度及其影响因素。     

万能材料试验机中交流伺服电机控制技术的研究

主要介绍了全数字式交流伺服电机在万能材料试验机控制系统中的应用,并给出了将松下MINAS A系列伺服电机用于5吨材料试验机的例子.分析了试验机复杂加载模式实现的硬件组成和软件设计,整个控制系统基于研华数据采集卡,应用系统软件则由LabVIEW进行编制,文章着重介绍了应用软件中的控制伺服电机的软件模块的功能、设计方法,以及实现策略.通过项目实施,证明这种设计具有直观、使用简单等特点,是切实可行的.     

高速摄影技术在包装跌落测试中的应用

提出了采用高速度摄影技术进行包装跌落测试与分析的新方法。重点研究了序列图像采集与分析的技术与方法,并以食品罐头跌落分析为例讨论了高速摄影技术在产品冲击研究中的应用,为包装产品跌落分析提供了一种新的研究思路。     

盾构管片拼装试验台监控系统设计

针对现有盾构管片拼装设备低精度、低效率、低可靠性的问题,以实现管片高效拼装为核心目标,设计了管片拼装试验台监控系统.在全面分析了管片拼装试验台的原理及监控需求的基础上,首先设计了以工控机为控制核心及以PCI数据采集控制卡为输入和输出模块的数据采集控制系统,接着分别设计了以软起动器为启停控制设备的动力电机电器控制线路及采用直接启动方式的风冷器电器控制线路,继而基于LabVIEW开发了可实现高速数据采集及实时控制的试验台监控系统软件,最后依据相关设计搭建了管片拼装试验台监控系统. 监控系统运行结果表明,硬件运算高速、可靠,软件设计合理、有效,该系统在试验台的操作过程及管片高效拼装方法的研究过程中发挥了重要作用.     

Implementation of a versatile research data acquisition system using a commercially available medical ultrasound scanner

This paper describes the design and implementation of a versatile, open-architecture research data acquisition system using a commercially available medical ultrasound scanner. The open architecture will allow researchers and clinicians to rapidly develop applications and move them relatively easy to the clinic. The system consists of a standard PC equipped with a camera link and an ultrasound scanner equipped with a research interface. The ultrasound scanner is an easy-to-use imaging device that is capable of generating high-quality images. In addition to supporting the acquisition of multiple data types, such as B-mode, M-mode, pulsed Doppler, and color flow imaging, the machine provides users with full control over imaging parameters such as transmit level, excitation waveform, beam angle, and focal depth. Beamformed RF data can be acquired from regions of interest throughout the image plane and stored to a file with a simple button press. For clinical trials and investigational purposes, when an identical image plane is desired for both an experimental and a reference data set, interleaved data can be captured. This form of data acquisition allows switching between multiple setups while maintaining identical transducer, scanner, region of interest, and recording time. Data acquisition is controlled through a graphical user interface running on the PC. This program implements an interface for third-party software to interact with the application. A software development toolkit is developed to give researchers and clinicians the ability to utilize third-party software for data analysis and flexible manipulation of control parameters. Because of the advantages of speed of acquisition and clinical benefit, research projects have successfully used the system to test and implement their customized solutions for different applications. Three examples of system use are presented in this paper: evaluation of synthetic aperture sequential beamformation, transverse oscillation for blood velocity estimation, and acquisition of spectral velocity data for evaluating aortic aneurysms.     

Study of static cushioning properties: Automated data input and reliability test of static cushioning properties

A computer-controlled compression testing machine is used to compile a database of the static cushioning properties of package cushioning materials. Through research into automated data input procedures, so far not developed, a direct transfer program (ZABCON) has been devised, which allows direct access to the disk in which compression test data are stored. Elimination of manual data input has led to simplified and easy construction of a database, and the applied laboratory tests, such as that for determining the relationship between static cushioning properties and compression rate, can be performed quite readily. Also in this report, the application of the static cushioning characteristics of foamed polystyrene in the cushioning package design of dummy goods and the evaluation of its reliability by drop testing are discussed.     

风扇试验台数据采集与处理系统

该系统为分布式测试系统,由二台前端数据采集与予处理机和一台中心数据处理机构成。具有低速、高速两种数据采集能力。每台前端机具有三十二路模拟信号来集、予处理、远程显示和数据通信功能,数据处理机主要完成前端机的初始化、数据通信、测试数据的实时处理和事后处理等任务。高速采集由高速A/D转换器实现,本系统可实现40kW/s的高速采集与测试数据的连续存盘。     

缓冲包装冲击试验机的研究与开发

介绍了一台集缓冲材料动态压缩和产品脆值两项试验功能于一体的包装冲击试验机,主要介绍了该设备的系统结构组成,数据采集、处理方式和实际应用方面的问题。     

Method for deriving the correlation between free fall and shock machine drop height

The purpose of this research was to investigate the correlation between shock machine drop height and free-fall drop height based on equivalent transmitted shock velocity change. The transmitted shock velocity change of shock machine impacts (using plastic 2 ms half-sine programmers) was measured with a waveform analyser, which is a part of the shock machine system. The transmitted shock velocity change of free-fall drops was measured using the same waveform analyser in conjunction with a trigger device developed specifically for this study. The data were then analysed and a correlation between free-fall drop height and shock machine drop height was derived, for a specific product/package system. For the shock machine and product/package used, the shock machine drop height was found to be equal to 1.31 + (0.74 × shock machine height). This equation will vary due to the dynamics of different product/package systems, different drop surfaces and the type of shock machine used.     

基于模糊Smith控制的热收缩包装机机械节能研究

目的 为了更加高效地提高热收缩包装机在机械节能控制方面的稳定性,优化控制器的控制性能。方法 在充分研究ARM Cortex-M3核心控制器LPC1500的基础上,利用嵌入式环境进行热收缩包装机的机械节能控制器硬件的开发,包括A/D采集模块、信息采集模块以及驱动执行模块等,结合模糊Smith在反馈调节上的优点,提高节能控制性能,再建立机械节能控制的控制器的约束参量的数学模型,进行机械节能方面的深入研究。结果 实验测试结果表明,采用模糊Smith设计的预估器性能更加良好,热收缩包装机节能控制可靠性高,并且能够降低包装机在能量方面的消耗。结论 在热收缩包装机控制方面采用的策略具有优化节能效果,具有广阔的市场应用前景。     

A data acquisition system for machine tool condition monitoring. Part 2—some of the signals acquired

This paper presents some of the machine tool condition monitoring signals logged by the data acquisition system (DAS) designed and implemented as part of the European Union research project BREU-CT91–0463. Cause and effect relationships between machine components and signal features are highlighted, along with a demonstration of the suitability of vibration signal kurtosis as a measure of machine tool spindle bearing condition.