用Slam Stick评估应用的能量采集振动数据

Mide Technology公司的能量采集器件采用的是谐振采集原理。为了从其环境冲最大限度地提取可用振动能量，采集器必须做调整以配合振动频率。要了解自己的应用是否适合于这种类型的采集，必须用一只加速度计来确定振动数据曲线。     

高压杆塔受迫振动数据采集系统设计

输电线路实时在线监测对于保证电网的安全稳定运行具有重大的意义,针对高压输电杆塔可能受到的外力撞击振动的实际情况,设计了以C8051F060为核心主控单元的高速数据采集系统。系统主要由信号调理、采集与分析三个部分构成。实验测试表明,系统运行稳定、可靠,采集高压输电杆塔振动数据送Matlab工具显示分析,能区别输电杆塔可能受到的外力破坏类型及撞击轻重,实时监测其振动状况,从而实现对杆塔运行状况的预警和评估,保障输电设备安全运行。     

基于TMS320VC5402的手持式振动测试仪设计

本文介绍的基于TI公司TMS320VC5402芯片的手持式振动测试系统，能对振动信号进行采集以及处理，并对处理的结果进行液晶显示，非常适合在野外工作。     

压电式振动能量采集装置研究进展

压电振动能量采集装置具有结构简单,能量密度高,寿命长等优点,在无线传感器网络、嵌入式系统和MEMS等低耗能电子设备自供电方面具有广阔的应用前景。针对提高振动能量采集能力和采集效率2个目标,根据设计压电振动能量采集装置的关键技术,从压电材料、压电元件工作模态、压电振子结构、振动支撑结构和共振频率调节方法等方面对压电振动能量采集装置的国内外研究现状进行了详细论述,指出了压电振动能量采集装置的研究前景。     

D-S证据理论在振源目标识别中的应用

本文采用D-S证据理论对振动目标脉冲宽度进行融合，可以很好地解决振动目标识别问题。地面目标激励产生的振动信号，主要受到运动状态、目标质量、传感器的距离以及地质条件等因素的影响。对传感器采集到的振动信号进行处理、特征抽取进而通过分类识别的方法可以确定产生地振动信号的目标类别[1]。     

基于LabVIEW的振动测试

在传统振动测试中，所需的仪器纷繁复杂。虚拟仪器图形编程语言可组建振动测试系统，利用“软件就是仪器”的技术方法，减少测试中的硬件设备，同样实现对振动信号进行实时采集、处理、分析的目的。现介绍了LabVIEW软件的原理和特点，分析了振动测试系统使用的各个功能模块的鳊程方法和实现技术。     

一体式无线无源振动传感器设计

现阶段无线传感器的供电主要依靠的依然是一次电池或可充电电池,无论哪种电池,其寿命都是有限且短暂的,大量的更换及废弃势必会对生态环境造成极大的污染。由此提出一种基于振动能量采集的自供电传感器,基于电磁感应对振动能量进行采集利用;低功耗单片机利用所收集的能量对发电单元所产生的信号进行采集,作为振动传感信号。实验结果证明,该无源传感器可在2 Hz^200 Hz的振动环境下稳定的工作,所采集的信号同样与实际振动环境一致。     

装甲车辆行进间火炮振动信号的采集与分析

装甲车辆行进间火炮的振动直接影响火炮的稳定精度,采集客观真实的火炮振动信号是火炮振动规律研究的基础。文章以火炮高低向为例,建立了信号采集的实验方案并进行了实车实验,最后对火炮振动信号进行了深入分析。     

基于分布式光传感的输电线路地震信号分析

为了分析地震对输电线路的影响,利用OPGW分布式光传感监测系统采集了地震案例数据,对输电线路受地震影响时的振动进行了特征分析,并初步尝试以实测塔线体系振动数据开展地震对输电线路的影响程度评估,充分验证了基于光纤复合架空地线(OPGW)的分布式光传感监测系统可以准确监测到输电线路通道的地震活动,并能感知全线路受地震波的影...     

振动对光电系统成像质量影响的试验研究

针对振动影响光电系统成像质量的问题,利用六自由度隔振系统和图像采集系统组合搭建了相应的模拟光电成像试验系统,通过振动台试验采集不同振动环境下的图像序列,对采集到的图像清晰度进行计算来分析振幅和频率等振动的参数对成像质量的影响。试验结果表明,对于光电成像系统,振动的振幅相比频率对成像质量的影响更大。对于不同频率的振动,在各阶频率的振幅相等的情况下,高频振动对成像质量的影响大于低频振动。试验研究成果对于探索和了解振动对光电成像系统成像质量影响的机理研究具有一定的参考和应用价值,同时对于工程实际中减振方案的设计和减震器的合理选择具有一定的指导意义。     

Active vibration control and real-time cutter path modification in rotary wood planing

Forced structural vibration and cutting tool inaccuracy have been identified to be the primary causes of surface defects in rotary wood planing. This paper presents the development of a control strategy used to compensate for the effects of both vibration and cutting tool inaccuracy on planed wood surface finish. The solution is based on active vibration control and real-time modification of the cutting tool trajectory using an optimal Linear Quadratic Gaussian tracking controller. A small-scale mechatronic wood planing machine, which has an actively controlled spindle unit, has been designed for practical investigation of the proposed technique. Experimental results show that the applied compensation increased the dynamic performance of the machine and the quality of the surface finish produced.     

六通道方位旋转关节技术研究

文中介绍了一种六通道方位旋转关节的设计方法,对旋转关节的整体布局、各通道旋转关节设计的关键技术进行了详细的介绍,并给出了测试结果.该旋转关节由一路X波段高功率波导通道、两路X波段低功率同轴通道及三路L波段同轴通道组成.整个旋转关节结构形式紧凑,各项性能指标优良,加工调试方便,可广泛应用于雷达及微波系统中.     

双通道组合旋转关节的设计

提出一种双通道组合式旋转关节结构原型,介绍设计该组合旋转关节时需要考虑的因素以及关键部分的设计方法,并且设计加工了一个C波段双通道组合旋转关节,给出了实验结果,验证了本方法的可行性.     

Theoretical and experimental investigations of vibration waveforms excited by an electro-hydraulic type exciter for fatigue with a two-dimensional rotary valve

Conventional electro-hydraulic excitation is usually controlled by a servo valve employing a sliding spool type construction. However, the comparatively slow response of the servo valve will greatly limit the system's high-frequency performance. Therefore, a rotary valve with the rotary motion of the spool as a new excitation mechanism is proposed to obtain the desired excitation, especially a high-frequency excitation wave for fatigue. An electro-hydraulic exciter using a combination of a three-way two-dimensional rotary valve (2D rotary valve) and an unequal area piston is taken as an example. Analysis of the vibration output to a typical wave input yields an analytic solution of the vibration waveform excited by this electro-hydraulic system. The mathematical formulation of the harmonics is also derived. Additionally, an electro-hydraulic excitation test-bed is built to acquire an experimental excitation wave. Consequently, the analysis of the excitation waveform in an approximate analytical and experimental method is used to verify access to high-frequency excitation, even resonance excitation.     

基于旋转变压器移相编码的工程设计

从理论和实践两个方面较为系统地论述了基于旋转变压器的移相编码原理及移相网络的公式推导，移相编码器的误差分析，可靠性分析以及调试方法等。     

Low-Power Rotary Clock Array Design

Rotary clock is a recently proposed clock distribution technique based on wave propagation in transmission lines. In this paper, we investigate the problem of power minimization of rotary clock designs. Specifically, we have developed a software tool based on the method of partial element equivalent circuit that is capable of extracting the SPICE netlist from the layout specification of a rotary clock design. Using our tool, we have performed extensive analysis that links various design parameters of a rotary clock design to its oscillation frequency and power dissipation. Based on the results of our analysis, we then propose a power minimization algorithm. Our algorithm derives a rotary clock structure that dissipates the minimal power while satisfying the clock dimension requirement and oscillating at the target frequency with the given clock load. Experimental results have demonstrated that, for target operating frequencies ranging from 0.5 to 5 GHz, rotary clock designs can achieve power savings of up to 80% in comparison with conventional clock tree implementations     

用UCDOS5.0SDK实现视窗及图表统计功能

本文介绍了利用UCDOS 5 0SDK工具在FOXPROFORDOS平台上实现三维窗口设计及统计图表三维显示的方法。它使得在FOXPROFORDOS平台上开发的应用程序具有FOXPROFORWINDOWS的屏幕效果。     

Towards a new tool for the evaluation of the quality of ultrasound compressed images

This paper presents a new tool for the evaluation of ultrasound image compression. The goal is to measure the image quality as easily as with a statistical criterion, and with the same reliability as the one provided by the medical assessment. An initial experiment is proposed to medical experts and represents our reference value for the comparison of evaluation criteria. Twenty-one statistical criteria are selected from the literature. A cumulative absolute similarity measure is defined as a distance between the criterion to evaluate and the reference value. A first fusion method based on a linear combination of criteria is proposed to improve the results obtained by each of them separately. The second proposed approach combines different statistical criteria and uses the medical assessment in a training phase with a support vector machine. Some experimental results are given and show the benefit of fusion.     

A statistical approach to characterizing the reliability of systems utilizing HBT devices

This paper describes a statistical approach to simulating the reliability of systems with HBT devices. Compared to the conventional worst-case method, the described approach utilizes statistical reliability information of the HBT individual devices, along with analysis on the critical paths of the system, to provide more accurate and more comprehensive reliability evaluation of the systems utilizing HBT devices.     

基于数字相关算法的动平衡测试系统的研究

针对大型旋转机械动平衡，从数字相关算法的角度深入地研究了多路动平衡测试仪器的信号处理算法在数字信号处理器（DSP）上的实现问题。充分利用DSP内部资源，开发了以DSP为核心的严格同步八通道数据采集系统，通过信号处理可以准确地从通频振动信号中提取出基频信号的幅值和相位，文中给出了具体软件处理思想和流程。