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1.
压电弹性耦合结构是实现MEMS微流体驱动的一种重要方式,掌握压电-弹性振动的耦合机理是微流体驱动协调控制的关键。针对压电与硅膜耦合微驱动结构,基于压电效应和弹性薄板理论,采用Rayleigh-Ritz能量法建立了周边固支边界条件下,弹性振动硅膜与压电驱动膜片耦合振动的理论模型,推导并计算了该微驱动结构的耦合振型及谐振频率。基于激光测振仪进行了该压电微驱动结构的振动测试实验,经实验模态分析获得了实测的谐振频率。理论计算结果与实验测试结果的对比分析表明,两者基本相符,验证了理论分析模型的正确性,为MEMS微流体的驱动与控制提供了一定的理论基础和实验依据。  相似文献   

2.
隆志力  吴运新  韩雷  钟掘 《电子学报》2008,36(2):255-260
研究了热超声倒装键合设备的核心执行机构——换能系统的动力学特性.利用激光多谱勒测振仪测试系统末端各方向的振动速度,发现系统以轴向振动为主,但受到其他非轴向振动的干扰.非轴向振动对芯片造成芯片倾斜、键合强度降低等负面影响.采用有限元方法对换能系统建模,仿真计算发现换能系统振动是各方向振动的耦合结果,且工作模态附近存在多种干扰模态.最后分析了系统多模态产生的根源并提出抑制方法.  相似文献   

3.
在热超声键合系统中,超声换能系统是键合装备的核心部分。基于等效电路法和解析法设计换能系统,获得换能系统的基本结构尺寸;基于有限元方法建立系统的仿真模型,获得系统的振动模态特性;采用阻抗分析仪与Doppler测振仪对系统进行性能分析。实验表明,实测频率与设计频率吻合,换能系统阻抗为12.7Ω,振动位移达到3.725μm,满足超声芯片封装的工艺要求。  相似文献   

4.
键合工具对超声换能器系统谐振频率的影响   总被引:1,自引:0,他引:1  
建立了超声引线键合机换能器系统振动分析有限元模型,利用ANSYS软件分析了换能器系统与键合工具组成的纵-弯复合振动系统的振动特性。计算结果表明,键合工具的弯曲振动与换能器系统纵向振动存在耦合关系,劈刀长度增加50%将使换能器系统谐振频率下降5.6%;实验中测试了换能器系统的阻抗与导纳特性,发现当劈刀长度为16 mm时系统的阻抗匹配较为理想;换能器系统的谐振频率的实测值与有限元分析结果一致,最大误差为3.51%。  相似文献   

5.
超声引线键合点形态及界面金属学特征   总被引:4,自引:0,他引:4  
采用超声键合的方法,研究了键合点的形成原因,通过SEM及EDX分析发现超声键合过程中存在扩散现象.对键合点进行了老化试验,考察了键合点上25μm直径的质量分数为Al 1%Si引线的组织演变情况,在170℃下,随着老化时间的延长,键合点上引线内部形成了大量的微裂纹和孔洞,连接成线,与超声振动方向平行,分析了产生原因以及对键合点可靠性的影响.  相似文献   

6.
芯片键合换能系统中接触界面的影响分析   总被引:1,自引:1,他引:0  
接触界面对超声能量传递与振动特性的影响是各类压电换能器的共性问题。在超声芯片封装领域,各子部分之间的接触界面是影响系统超声能量传递的强非线性因素,直接影响芯片与基板的键合质量。该文通过有限元法与激光多谱勒测振仪等技术,获得系统中接触界面对超声能量传递与振动特性的影响规律,发现不合理的接触界面会引发系统多模态与频率混叠效应、超声能量输出不稳定、系统迟滞响应等,导致键合强度下降、芯片与基板倾斜、键合效率下降等封装缺陷。研究结果对理解超声键合与系统设计具有指导意义。  相似文献   

7.
孙亚飞  黄硕 《压电与声光》2014,36(5):739-744
首先对压电堆驱动器的静态驱动特性进行了系统的理论分析,为压电堆驱动器的结构设计奠定理论基础。在此基础上,对压电堆驱动器的动态驱动特性及其结构模态等的测试方法进行了研究,从而为压电堆驱动器有效的应用于各类微振动主动控制系统奠定基础。最后设计并制作了一台大位移压电堆驱动器,对其各项性能进行了理论计算和实验测试,结果达到了预期设计要求,并成功应用于某微振动主动控制系统中,取得了良好的主动振动控制效果。  相似文献   

8.
通过调节微合金元素的含量获得3种具有不同力学性能的银键合丝.利用拉伸试验、键合试验、焊线挑断力、焊球推力测试等手段,研究了银键合丝力学性能对键合质量的影响.结果表明,在延伸率相同的条件下,随着微合金元素含量的降低,3种键合丝的断裂负荷降低,初始模量先减小后增大,键合后焊线挑断力和焊球推力均降低,电极金挤出率先减小后增大.银键合丝初始模量较低时在超声和压力的作用下易于变形,焊线内残余应力较低且第二焊点与引线框架结合较好,因此挑断测试时第二焊点与框架材料界面处不易发生脱离,有利于获得更高的键合成功率.  相似文献   

9.
利用Pro/E与ANSYS联合仿真,对不同材料、 丝径、 键合形式和跨度的键合丝的振动应力极限进行了分析研究.基于键合工艺及其特点在Pro/E中建立了键合丝参数化三维模型,并利用ANSYS对参数化模型进行了模态及随机振动仿真分析,获得了球键合金丝与楔键合硅铝丝在不同丝径、 跨度等条件下的极限功率谱密度,研究结果可为键合丝的选型提供参考.  相似文献   

10.
换能系统是热超声引线键合装备的核心部分,夹持环对系统起安装支撑的作用,其安装方式直接影响换能系统的能量传递与振动模态。利用有限元法分析了夹持环对换能系统振动模态的影响,结果表明,对夹持环未施加约束、施加z向约束时换能系统的夹持环会出现振动现象,而施加x向约束时,工作频率下的主振型完全不符合要求;改变夹持环的安装位置,对换能系统的节点位置及谐振频率都有一定的影响,实验测得在全约束情况下,换能系统的节点位置为58 mm,与分析结果一致;换能系统在工作频率附近包含有其他的振动模态,在键合过程中易被激发出来,由此消耗超声能量而降低芯片的键合质量,这些振动模态必须得到抑制。  相似文献   

11.
This paper addresses the simultaneous control of vibration and static shape deformation of arbitrarily shaped thin-walled flexible payloads. During robotic assembly of these thin-walled parts, gravity and inertial forces acting on the parts may induce both static shape deformation and vibrations in the part sufficiently large that accurate and high speed assembly of these parts is hindered. Static deformations, which arise due to deformation of the part caused by its own weight under the influence of gravity, lead to misalignment of mating points of the parts. Unwanted vibrations, arising from inertial forces acting on the thin-walled parts as they are positioned for assembly, must damp out before parts can be mated, further hindering the process. In this work, a smart gripper with actuated contact points to grasp the flexible thin-walled parts is proposed to solve this problem. The smart gripper is capable of both part reshaping and active damping of unwanted vibrations of the part. It is fixed to a robotic manipulator and is comprised of multiple linearly actuated fingers with laser-based noncontact proximity sensors, and associated signal processing and controllers. In this paper, a simultaneous vibration and static shape controller is developed. The proposed controller is a composite modal controller in conjunction with a quasi-static modal filter and a bias Kalman filter, which is synthesized based on the reduced-order dynamic model of the flexible payload. A near industrial practice demonstration of the feasibility of the proposed approach is carried out using a proof-of-concept smart gripper to manipulate an automotive fender. Experimental results indicate that unwanted vibrations are successfully damped out, allowing faster cycle times for an assembly process, and static shape deformations are corrected, allowing accurate positioning of parts for assembly.  相似文献   

12.
Sawn kerf, wafer profile error and wafer subsurface damage were systematically measured and were used to evaluate the materials loss for the sapphire slicing with the fixed diamond wire. The vibration of saw wire was also measured during the slicing process. The impact of each part on the materials loss was discussed. The effect of the wire vibration on the materials loss was explored. It was found that the sawn kerf loss and the wafer profile error loss were the main forms of the materials loss during the slicing process. Wire vibration has significant influence on sliced wafer morphology. Influence of slice parameters on the kerf loss is similar with the case on the vibration amplitude, which indicates that the wire vibration is the key factor to cause the kerf loss. Wire slicing model with the wire vibration is established to understand the influence of wire vibration on the materials loss.  相似文献   

13.
丁严  赖磊捷 《压电与声光》2019,41(4):562-565
该文设计了一种两级放大的新型柔性微夹钳结构,对其位移放大比等特性进行了研究。首先,设计了微夹钳的整体结构,第一级放大机构采用杠杆机构,第二级采用半桥式放大机构。随后,利用刚度矩阵法对微夹钳柔性机构进行建模分析,并建立了平面三自由度的振动微分方程,根据所得方程计算出了微夹钳的位移放大比等特性。最后分别利用有限元和实验方法对模型分析得到的位移放大比进行了验证。结果表明,模型分析、有限元分析及实验的结果较吻合,证明了此微夹钳柔性机构以及建模方法的可行性和有效性。  相似文献   

14.
纵向振动单一超声变幅杆是热声焊机换能器中的关键零件,其作用是放大换能器所获得的超声振动振幅.为了得到最大的振动幅值,变幅杆固有频率应和超声波发生器的工作频率相同.运用ANSYS有限元分析软件进行了不同材料下的变幅杆固有频率的模态分析,验证了1Crl8Ni9Ti不锈钢的变幅杆的纵振固有频率与工作频率相一致,给出了纵振模拟图和位移图,并对模态分析结果进行了研究,以了解在给定的频率范围内各种模态形式,通过采取一定方式抑制接近工作频率的影响键合质量的非工作模态产生.  相似文献   

15.
In this paper, a couple thermal mechanical transient dynamic finite element framework of copper wire bonding process on high power lighting emitting diodes (LEDs) is developed, which considers the thermal heating effects of friction and plastic deformation. The whole wire bonding process is simplified to consist of impact and ultrasonic vibration stages. Parametric studies are also carried out to examine the effects of ultrasonic vibration amplitude and bonding force on stress/strain distribution and friction thermal heating effect during wire bonding process. Different friction coefficients of interface between the free air ball (FAB) and the bond pad are taken in the simulation to examine the effects of friction on the stress and strain level of electrode structure. Modeling results show that the stress/strain distribution and temperature evolution of wire bonding system are significant influenced by the ultrasonic vibration amplitudes, bonding forces and friction coefficients. Discussion and comparison are conducted between the copper and the gold wire bonding processes on the high power LEDs by numerical simulation. The results have disclosed that higher stress/strain in the bond pad and the ohmic contact layer is induced during the copper wire bonding process. Therefore, the process parameters of copper wire bonding should be controlled carefully. This numerical simulation work may provide guidelines for the copper wire bonding process virtual window development of high power LEDs packaging.  相似文献   

16.
This paper proposes a new flexure-based dual-axis gripper driven by two piezoelectric actuators (PEAs). For achieving two degree-of-freedom (2-DOF) micromanipulation in terms of grasping and rotating operation, the gripper is designed with an asymmetric structure which can be divided into left and right parts. Each part of the structure includes a two-stage amplification mechanism to accomplish displacement enlargement and motion transmission. Three groups of strain gages are integrated to measure the jaw displacements and the gripping force. To realize decoupling between the grasping and rotating function, the motion-guiding mechanisms of the two parts are elaborately designed with an orthogonal configuration. Analytical models of the gripper are derived using pseudo-rigid-body model (PRBM) method. Finite-element analysis (FEA) simulations are conducted to obtain the optimal geometric parameters and to evaluate the performance of the gripper. A close-loop position/force switching control strategy based on incremental PID algorithm is proposed to compensate the hysteretic nonlinearity of PEAs and guarantee precise and stable operation of the gripper. After that, a prototype gripper is developed and experimental investigations are conducted to verify the effectiveness of the gripper by executing a grasping-rotating-releasing operation of a metal wire. The experimental results indicate that the proposed gripper is capable of delicate and dexterous micromanipulation.  相似文献   

17.
Although flip chips have received wide acceptance as an integrated circuit package, significant manufacturing problems exist with the integrity of the connection between the package and the printed circuit board (PCB). Conventional X-ray, ultrasonic and electronic testing systems have been used to assess the integrity of this connection, however, none of these have proven suitable for detecting open solder bumps between the chip and the board. The inability to detect open solder bumps with traditional methods merits the investigation of new, nondestructive methods for detecting defects in a manufacturing environment. This work assesses the feasibility of monitoring the vibration characteristics of flip chips to detect open solder joints. Test vehicles with open solder joints were created, and a nondestructive laser ultrasonic system was used to measure the free vibration response of the chips attached to the printed circuit board. The algorithm of mode isolation (AMI) was applied to the vibration response data in order to extract the modal parameters of the chip. The statistical differences between the modal parameters of sets of damaged and undamaged chips were assessed, revealing the ability of the method to determine the location and severity of these defects in the presence of experimental scatter and manufacturing variation. The parameters of the first mode of vibration, especially its mode shape, were found to be much more sensitive to damage than those of a higher frequency mode.  相似文献   

18.
金属丝阻尼减振器在电子设备隔振系统中的应用   总被引:4,自引:0,他引:4  
金属丝阻尼减振器是目前较为新型的隔振器,其中钢丝绳隔振器愈来愈广泛地应用于电子设备的隔振系统中。简要说明了振动对电子设备的危害,并阐述了金属丝阻尼减振器的特点及其在电子设备的隔振系统中的应用。  相似文献   

19.
应用压电器件实施丝振主动控制的研究   总被引:2,自引:2,他引:0  
本文提出利用压电传感器和致动器主动控制技术解决线切割机的铝丝振动问题。实验结果证明:主动控制技术可以有效地抑制钼丝振幅值与提高加工质量。  相似文献   

20.
The modal equations for both the monofilar and bifilar modes of a two open wire transmission line located in a waveguide model of a rectangular mine tunnel are derived by extending an earlier general analysis. Attenuation curves of both modes in the frequency range 200 kHz-200 MHz are presented for two distinct configurations of the transmission line that may be used in practice. It is demonstrated that the proximity of the Iossy tunnel wall tends to increase greatly the attenuation rate for the monofilar modes but has relatively little effect on the bifilar modes.  相似文献   

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