DVD激光读取头音圈马达寻迹静态特性研究

采用CCD的图像边缘检测方法测量DVD激光读取头音圈马达（VCM）寻迹的静态特性。通过系统的架设测量音圈马达驱动电压与音圈马达弹性臂影像在CCD中对应的位置，经过图像边缘检测软件处理，得到音圈马达寻迹单方向的驱动电压与对应位移的关系。实验结果表明，音圈马达寻迹单方向的线性范围大约为300μm，双方向运动为600μm，从实验曲线数据处理得到线性范围内存在的磁滞误差，并对磁滞误差进行了分析。     

基于激光多普勒技术的三维扫描测振研究

振动测量是现代工程技术中重要的检测和分析手段,振动测量的设备从接触式发展到非接触式,从单点测量发展到面扫描测量、三维方向振动测量,进而提出了三维扫描振动测量。提出一种三维扫描振动测量的方法及系统解决方案。该系统由3台单点LDV、3套振镜、2套视频采集系统组成。通过视频采集系统和振镜马达可闭环控制激光光点在前方被测表面的扫描,扫描过程中3套单维激光测振仪的光束聚集于一点,实现某点的三维振动精密测量,控制振镜马达的转动,可扫描整个面上的三维振动信息。     

基于光学相干层析的结构振动监测研究

针对光学非接触式的振动测量问题,对基于频域光学相干层析技术搭建的振动测量系统进行了研究,通过记录位移随时间的变化实现了对振动信号的测量。研究了振动测量过程中,光谱仪采集的干涉条纹的模糊现象与被测目标瞬时速度的关联;建立了系统可测量的最大振动频率和CCD相机的曝光时间之间的关系,即曝光时间越短,则系统可测量的振动频率越大;对函数信号发生器驱动激振器产生的振动信号进行了测量试验。研究结果表明:光学相干层析技术是一种有效的光学非接触式振动测量方法,在基于振动的结构健康监测领域具有广阔的应用前景。     

振动压路机振动原理及振动失灵的排查方法

<正>振动压路机振动液压系统是其液压系统的重要组成部分,振动液压系统驱动振动轮振动,完成路面振动碾压作业,其性能决定了振动压路机的压实效果。本文在说明振动液压系统工作原理基础上,提出振动失灵故障的排查方法。1.振动液压系统工作原理振动压路机电控系统对振动液压系统的振动泵进行控制,使振动泵输出的压力油驱动振动马达以不同转速进行正、反转转动。振动马达通过     

平面式大型微结构表面的螺旋扫描测量

为实现平面式大型微结构表面的快速测量,提出了一种螺旋式扫描测量方法。基于该方法的测量系统由x、y、z向直线运动平台、绕z轴旋转的直接驱动(DD)马达以及激光位移传感器组成,当移动x、y向平台使激光位移传感器的激光束与DD马达的旋转中心重合,并通过z向平台使激光位移传感器位于其测量范围内时,使x向平台与DD马达同步运动而形成螺旋线来获得被测表面形貌的平面位置信息,同时由激光位移传感器获得被测表面的高度信息,据此实现对被测表面形貌的测量;这种螺旋式扫描方法避免了栅格式扫描方法所存在的频繁加减速及反向运动间隙不足的问题,可提高系统的测量速度和精度。基于所搭建的测量系统,对表面形貌为凸凹扇形的圆形试件的表面进行了测量,结果表明:所提出的螺旋式扫描方法能够实现表面三维形貌的快速测量,测量试件表面上直径为Φ20 mm的区域时,所用时间仅为800 s,测量结果能较好地反映被测试件表面形貌的三维形貌。     

S0910型轴承振动测量仪台差原因分析

针对日常检测用S0910型轴承振动测量仪之间的台差,从其传感系统、机械驱动装置及测量电箱等方面进行试验分析,结果表明,造成测振仪之间测值差异的主要原因是机械驱动系统的基础振动。     

基于衍射光栅计量系统的非接触轮廓测量位移传感器

聚集检测法是一种非接触轮廓测量方法,但是现有的聚焦检测法采用音圈电机,其测量精度有限.针对此问题,文中提出了一种非接触位移传感器,该传感器基于改进的傅科聚焦检测法,并带有衍射光栅计量系统.通过压电驱动器取代音圈电机驱动,并配合位移计量系统,提高了传感器的测量精度.在表面轮廓采样时,根据聚焦偏差信号,压电驱动器驱动聚焦透镜作垂直运动,使焦点始终在工件表面,同时衍射光栅计量系统测得聚焦透镜的垂直位移并将其作为采样点的轮廓高度.所有采样点的位移显示出被测量表面的整个轮廓,评定软件处理这些位移数据即可获得测量结果.该非接触的位移传感器的分辨率为10 nm.     

DZ系列纺锭轴承振动测量方法

针对DZ系列纺锭轴承结构特点所造成的振动测值不稳、测量重复性差的问题,通过对测量夹具、测量载荷、驱动芯轴、测振润滑等因素的试验与分析,结合ISO 15242-4:2007标准对圆柱滚子轴承振动测量的推荐建议,提出了DZ系列纺锭轴承振动测量方法,该测量方法已被中国纺织行业标准FZ/T 92025—2008采纳,可供轴承制造厂产品质量评价内控参考。     

基于音圈电机的主动悬架双闭环控制系统研究

为了提高电磁式悬架主动控制的性能,简化作动器结构以及控制系统,设计一套以单相两极的动圈式音圈直线电机作为作动器的主动悬架控制系统。设计了外环模糊PID,内环电流滞环的双闭环控制器。搭建了作动器驱动电路,验证音圈电机的电流跟踪控制,证明音圈电机作为作动器是简单有效的。通过分析汽车悬架模型和音圈电机模型,在MATLAB/Simulink仿真环境中按照实际参数搭建控制系统进行仿真验证,结果表明,该系统动态响应快,控制精度高,降低车身振动加速度约27%,该控制策略可以有效减振。     

压路机行走液压系统故障的测压诊断

全液压振动压路机一般都设有测压日，并配置了液压油压力测试仪表。因此，如何利用测压的方法来快速诊断故障值得重视。压路机行走液压系统的常见故障有：整机不能行走。驱动功率太低及行走不平稳跳动等。下面以YZ18GD全液压振动压路机为例（见附图），介绍通过测压诊断上述故障的方法。该机液压系统的最高溢流压力为42MPa，工作压力取决于负载，溢流压力是指阀两端的压力差，测量值为42MPa十补油压力。补油压力为2．4MPa，测量值为2．4MPa十壳体压力。液压泵、马达壳体压力最高为0．3MPa，冷起动时最高压力为0．5MPa。测压时只需将6…     

基于三次加速度曲线的巷道式堆垛机仿真分析

随着堆垛机向高速化方向发展,立柱的摆动问题日益重要。本文以昆明船舶设备集团研发的TD115单立柱堆垛机为例,采用MSC／Adams模拟分析了堆垛机加速度大小及平顺性对其振幅的影响,分析仿真的结果表明：通过采用基于三次曲线的加速度控制方法,可以使加速度变化平滑,从而降低立柱摆动。最后,提出了基于三次曲线加速度的堆垛机控制策略。     

Clearance Influence on Dynamic Response of Intermittent Roller Chain Drive

The clearances appear in chain link hinges induced by manufacturing tolerance or wear of components are the most important factor that influences the dynamic performance of the intermittent roller chain drives.Due to the existence of the clearances in chain link hinges,the serious impact vibration phenomenon which influences the stability and the position accuracy of the chain drive system would be caused in the intermittent motion.But,the problem may be that a reasonable modeling on the chain with clearances is difficult due to the large clearance's number in chain system and the fact that the clearance' size are different.Currently,the studies on the dynamics of the intermittent roller chain considering the multi-clearance' joints are rare.Most research works have only focused on the constant moving chains.Taking the intermittent roller chain system as an object,this paper designs and builds the experimental device of this kind of mechanical system.The Longitudinal vibration response of the intermittent chain under the different motion laws was tested.The experimental study shows that the clearances presented in chain link hinges can cause severe impact vibration in the intermittent motion of chain.In subsequent work,the dynamic model of the intermittent roller chain system with the multi-clearance' joints was established.By calculating the dynamic response of this kind of mechanical system under the different motion laws,the effect of the clearances on the dynamic response of the intermittent chain drive system was analyzed.The theoretical simulation shows that the serious impact vibration phenomenon of the chain system can be caused by the clearances at the start accelerating period,and the chain drive system is often accompanied by the severe shock and vibration at the moment that the chain moves from the acceleration period to deceleration period.The research conclusions made by the experimental and theoretical studies indicate that the use of motion laws with small and continuous jerk at conversion point can effectively suppress the impact vibration at this point caused by clearances' effect.Additionally,the use of nonsymmetrical motion laws with small jerk approaching the end of the indexing period can obtain a smaller residual vibration.The presented motion law can provide an important reference for the improvement of the dynamic performance of the intermittent chain drive systems.     

旋转机械耦合传动系统参激振动分析与控制

以一类旋转机械传动系统的扭振为研究对象,考虑轴系时变刚度变化和非线性摩擦阻尼力的影响,根据Lagrange原理建立了一类旋转机械传动系统的耦合非线性动力学方程,利用多尺度方法推导出了系统的平均方程,并根据Hopf分岔理论给出了系统发生Hopf分岔的充要条件及周期运动稳定性的判别方法,分析了参数共振和内共振条件下系统的分岔特性。为抑制传动系统因亚临界Hopf分岔引起的失稳振荡,引入非线性反馈控制,对系统的Hopf分岔点进行转移并控制周期运动的稳定性和幅值。研究结果为非线性旋转机械参激振动的分析及控制提供了有效方法。     

船用舵机两种液压驱动方式振动噪声对比试验

液压驱动是目前船用舵机的主要驱动方式,其振动噪声不仅会影响系统的平稳运行、人员的健康舒适,还会对设备和元件的寿命产生影响,因此,振动噪声水平是现代船舶装备设计的关键指标之一。针对双柱塞缸对称驱动及单柱塞缸非对称驱动典型船用舵机,通过容积控制和节流控制两种方式,进行了两种舵机系统振动噪声的对比试验,探讨了不同驱动方式、不同驱动速度等因素对船用舵机振动噪声的影响。结果表明:采用阀控双柱塞缸对称驱动可有效降低舵机系统的振动噪声。     

Mechanism analysis and suppression strategy research on permanent magnet synchronous generator wind turbine torsional vibration

Torsional vibration of flexible drive chain is a historical issue. With the maximization development and the rotating machinery high-speed operation, the drive chain systems of large-scaled units become more and more complex, which makes the torsional vibration problems becoming increasingly prominent in recent years. This article deeply analyzed the small signal stability of large-scaled WECS based on CMT, elaborated the torsional vibration mechanism and reasons for the first time and pointed out torsional vibration is caused by the disturbance wind and the DPC strategy. The disturbance wind is an external stimulus and can produce a low-frequency torsional vibration at the same frequency as wind speed. The DPC could weaken the drive chain damping. If the total damping of drive chain is negative, the unstable torsion vibration will occur. And if the drive chain is still a under-damped dynamic, the high-frequency torsional vibration at natural frequency will be generated. Therefore, large-scaled WECS must have damping control. This study found that appropriate enhancing drive chain stiffness could reduce low-frequency torsional vibration caused by wind speed. Therefore, a damping and stiffness compensation control method was proposed to suppress the torsional vibration. Compared with the conventional damping control, the new method not only can suppress the high-frequency torsional vibration but also has a good restraining effect on the low-frequency torsional vibration. Furthermore, the detailed design procedures including the calculation of injection damping and stiffness were given in this paper. Finally, the correctness and effectiveness of our analysis were further verified by the simulation experiments     

Measurement of real normal modes with adapted resolution by means of a continuously scanning laser vibrometer

This article presents a method of measuring mode shapes for a sinusoidally excited structure using a continuously scanning laser Doppler vibrometer (LDV). The LDV output signal is an amplitude-modulated vibration in which the excitation signal is modulated by the complex deflection of the excited structure. The mode shape can be derived along a scan path by the envelope of the modulated vibration using an applicable demodulation. For an optimised identification of the tuned mode shape, it is possible to adapt the scan path to the characteristics of the selected mode shape. Therefore, the laser beam is driven with varying instead of constant scan frequencies over the surface of the test object during one scan. An algorithm is presented to derive an applicable function for the mirror drive signals from the measured deflection along the scan path. The algorithm calculates the gradient of the measured responses and derives an optimised scan path. Hence the resolution and sampling rate can be adapted to the characteristics of the tuned mode.     

超声波驱动的摩擦特性研究

采用自制的模拟超声马达定子齿椭圆振动的超声驱动模拟试验装置，研究了接触预压紧力和两相超声波振动的激励电压峰峰值之比对超声驱动的摩擦特性的影响。结果表明：在超声波振动驱动条件下，每一种摩擦材料都存在最佳的预压紧力和激励电压的组合。     

闭环双驱动混合输出六自由度并联机构运动分析

提出一种分支含闭环双驱动单元、可实现混合输出的六自由度并联机构。分析了动平台混合运动时驱动分支的等效形式,以及独立位姿运动和振动时驱动分支的等效形式;分析了混合运动关于位姿运动输入和振动输入的位置反解,对振动输入的位置反解设计了基于机构运动特点的逐次逼近法;运用螺旋理论求得动平台混合运动时关于全体12个独立广义坐标的一、二阶影响系数,得到从广义输入到动平台旋量速度、加速度的线性映射;通过数值算例分别对位姿运动输入和振动输入的理论分析结果进行了验证,算例仿真表明,提出的两种双驱动输入分配计算规则均能得到确定的混合运动输出。     

带式啮合介质齿轮传动动力学性能分析

针对带式啮合介质齿轮传动中存在的动力学性能问题,首先建立了考虑齿轮啮合刚度、误差激励、介质带阻尼等参数的带式啮合介质齿轮传动系统简化振动模型,然后利用Solidworks软件对带式啮合介质齿轮传动系统进行了实体建模,最后导入ANSYS有限元分析软件对该模型进行了动力学性能分析仿真。研究结果表明：介质带的存在没有改变齿轮传动过程中的应力变化规律;带式啮合介质齿轮传动相比普通渐开线齿轮传动,其振动幅度减小,振动周期增大,介质带的存在改变了传动系统啮合刚度和啮合阻尼,起到了减振降噪的作用。     

振动钻削中轴向平均切削力的理论研究

振动钻削特殊的切削机理能显著降低钻削过程中的切削力。通过分析振动钻削过程中的钻头运动,推导了钻头在切削过程中所受轴向平均切削力的理论计算公式,并据此对振动钻削过程中切削参数和振动参数对轴向平均切削力的影响进行了定性分析。