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提出了使压电陶瓷传感器在采样间隔内作执行器、并应用于振动主动控制的方法。一个传感执行周期包含传感时隙、执行时隙和放电时隙,依次进行振动测量、振动控制和释放残留电荷。由时序电路控制三个时隙的切换,论述了时序设计和开关选取等技术细节。实验证明了传感功能和执行功能在时间上的切换不影响压电元件的传感效果,执行能力取决于执行时隙与传感执行周期之比。在对悬臂梁进行模态分析的基础上,采用独立模态控制和线性二次型最优控制算法,将分时复用的压电传感器和执行器用于悬臂梁一阶模态的振动主动控制,结果表明控制后悬臂梁的振动衰减时间缩短为控制前的20%。 相似文献
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本文针对板的振动,提出了一种无需次级通道建模的分散式前馈控制方法。该前馈控制方法不需要结构的物理信息,并且能够控制板在非共振频率处的线谱振动。采用压电片和加速度计分别作为执行和传感元件,建立了简支板振动主动控制的理论模型和实验系统。提出了分散式前馈控制策略,并分析了无需次级通道建模的分散式前馈控制算法的稳定性。提出了一种内模滤波器将加速度信号转变为速度信号,并补偿抗混叠滤波器和平滑滤波器的频率响应,使执行器和传感器保持同位配置。通过仿真和实验验证了该算法的有效性。 相似文献
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压电振动能采集器是无线传感节点的一种理想电源,近年来受到广泛关注.考虑质量块和逆压电效应影响,建立了在基础激励作用下的悬臂梁压电振动能采集器的集总参数运动微分方程,得到了采集器固有频率的解析表达式.引入了2个反映压电层连接方式的常数,建立了对单压电层、双压电层并联和双压电层串联的悬臂梁压电振动能采集器均适用的耦合电路方程.求解以上方程,得到了简谐基础激励下的输出电压表达式.实验结果表明,固有频率和输出电压表达式的相对误差分别小于10%和20%. 相似文献
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研究了带末端质量块的悬臂梁压电振子多模态振动时的应变分布特点,针对压电陶瓷表面电极配置对压电振子输出电压的影响关系进行压电-电路耦合有限元分析,并建立悬臂梁压电振子发电测试系统,对工作在一阶和二阶谐振频率附近处的压电振子分段电极和连续电极输出功率进行对比分析。研究结果表明,一阶谐振时分段电极的峰值输出功率与连续电极相接近,二阶谐振时分段电极的峰值输出功率增加了900%。相比于连续电极配置法,分段电极配置法可有效提高压电振子在高频振动时的发电能力。 相似文献
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用压电元件实现复合材料层合板振动控制的数值分析 总被引:9,自引:0,他引:9
采用板的一阶剪切变形理论,对含有压电材料层的复合材料层合板,从机电耦合的变分方程及Hamilton原理出发,建立起求解其动态响应 的有限元方程。同时也给出了压电材料层作为传感元件时的传感方程及作为作动元件时的作动方程。并采用速度反馈控制实现了层合板的主动振动。最后给出了计算实例。 相似文献
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Vibration suppression of laminated composite beams with a piezo-electric damping layer 总被引:1,自引:0,他引:1
An analytical formulation is derived for modelling the behaviour of laminated composite beams with integrated piezoelectric sensor and actuator. The major difference in approach to the solution compared to previous studies is that the analytical solution for active vibration control and suppression of smart laminated composite beams is presented in this paper. The governing equation is based on the first-order shear deformation theory (Mindlin plate theory), which is applicable for both thin and moderately beams, and includes the coupling between mechanical and electrical deformations. The voltage generated by the sensor layer and response of the beam to the actuator voltage can be computed independently. In this study, the new assumption of harmonic vibration is introduced, which includes both of the sine and cosine terms. Another contribution of this paper is introducing the transformation method of complex numbers to reduce the order of the governing equation of smart laminated beams. Thus, the exact solution of the reduced governing equation can be obtained by using MATLAB and the entire numerical results are presented. The behaviour of the output voltage from the sensor layer and the input voltage acting on the actuator layer is also studied. Graphical results are presented to demonstrate the ability of closed-loop system to actively control the vibration of laminated beams and it shows a good control effect. The influence of stacking sequence on the controlled transient response of the laminated beam is examined. Finally, the experiential formulation of the amplitude of beam vibration varying with the negative velocity feedback control gain has also been evaluated. The present method has a general application in this field of study. 相似文献
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压电梁振动的多输入多输出主动控制 总被引:1,自引:1,他引:1
对表面上贴有多个用作驱动器和传感器的压电陶瓷片的“压电梁”结构,导出了从驱动器到传感器的频响函数公式,作为压电结构设计和振动控制的数学模型。提出了压电梁对缓变周期扰动振动环境的多输入多输出振动抑制方法。 相似文献
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针对表面粘贴有压电层的功能梯度板的动力学及主动振动控制问题,建立了一种基于三阶剪切变形理论的等几何分析求解方法。其中,功能梯度板的材料属性为板厚方向的幂函数分布,并假设电势沿着压电层的厚度方向呈线性变化。利用线性压电本构方程以及哈密顿变分原理,推导了压电功能梯度板的相关等几何分析有限元方程。通过分析压电智能结构的静态弯曲行为验证了该方法的有效性与精确性。运用模态叠加技术与Newmark-β直接积分法分析了两种不同结构的压电功能梯度板的动力学响应与主动振动控制问题。在主动振动控制分析中,引入了物理中面的概念避免当传感器与驱动器分别粘贴于功能梯度的上、下表面时,由拉伸-耦合效应引起的控制不稳定的问题,并着重分析了振动控制过程中两种结构传感器层和驱动器层的电压响应。 相似文献
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Delamination is one of the most prevalent failure mechanisms for laminated composites. To secure the safety of composite structures, it is required and necessary to develop cost-effective and efficient delamination detection techniques and methods. In this paper, a dynamic analytical model, namely sensor charge output deviation method is proposed to identify a delamination embedded in a cantilever laminated composite beam bonded with isolated piezoelectric actuator and sensor patches. Two pairs of collocated piezoelectric patches are bonded on top and bottom surfaces of the beam and used as actuators for exciting the composite beam. Another piezoelectric patch with gridding electrode pattern on its top surface is bonded on the top surface of the host beam and is employed as a sensor to record the required voltage and thus the sensor charge output along the beam. The effects of some major geometric parameters and the type of applied electric voltage on the sensor charge output distribution and delamination detection sensitivity are discussed in this paper. A comparison between the analytical models using isolated piezoelectric actuator and sensor patches and that using integrated piezoelectric sensor/actuator layer, which was developed previously, is conducted. For the baseline case considered here, there is an excellent agreement of the first three order frequencies between the present finite element analysis and analytical models. 相似文献
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研究了一种基于谐波磁场磁链测量原理的磁流变(magnetorheological, MR)阻尼器的振动自传感技术,实现了相对位移传感器与磁流变阻尼器的结构复用与功能集成,建立了基于快速控制原型技术的磁电式自传感磁流变阻尼器的原型.实验测试结果表明集成于自传感磁流变阻尼器的磁电式相对位移自传感器基本达到通用LVDT的传感性能. 相似文献
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A High-Resolution MEMS Piezoelectric Strain Sensor for Structural Vibration Detection 总被引:1,自引:0,他引:1
《IEEE sensors journal》2008,8(12):2027-2035
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Active damping of piezo-composite beams 总被引:1,自引:0,他引:1
The aim of the present study is to investigate the effects of piezoceramic materials on the active damping of vibrating piezo-composite beams. The active damping is obtained by using an actuator and a sensor piezoceramic layer acting in ‘closed-loop’. By transferring the accumulated voltage on the sensor layer to the piezoelectric actuator layer, the beam can actively damp-out its vibrations. An exact mathematical model, based on a first order shear deformation theory (FSDT) is developed and described. This model allows the investigation of piezo-composite beams with two actuation/sensing type mechanisms, extension and shear. The present study is confined to symmetric lay-up beams using continuous piezoelectric layers. Using the present model, both natural and damped vibrations are calculated. The effects of the feedback gain, G, and the beam length on the damped vibrations are investigated and presented. 相似文献
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基于经典的层合板理论和Navier解法,对静水压作用下压电弹性层合圆柱壳的动力问题的主动控制进行了研究。首先由Hamilton原理导出压电弹性层合壳的非线性动力基本方程。利用压电材料的正、逆压电效应,通过闭环方式,采用速度反馈控制方法得到了任意形式动载作用下带压电感测层/激励层的简支层合圆柱壳动力响应的主动控制模型。数值算例中对于三种不同的外载条件下该控制模型对圆柱壳的动力响应的控制效果进行了研究。结果表明本文中提出的控制模型能够有效抑制动载作用下结构的振动。 相似文献
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An analytical method on active vibration control of smart FG laminated cylindrical shells with thin piezoelectric layers is presented based on Hamilton’s principle. The thin piezoelectric layers embedded on inner and outer surfaces of the smart FG laminated cylindrical shell act as distributed sensor and actuator, which are used to control vibration of the smart FG laminated cylindrical shell under thermal and mechanical loads. Here, the modal analysis technique and Newmark’s integration method are used to calculate the dynamic response of the smart FG laminated cylindrical shell with thin piezoelectric layers. Constant-gain negative velocity feedback approach is used for active vibration control with the structures subjected to impact, step and harmonic excitations. The influences of different piezoelectric materials (PZT-4, BaTiO3 and PZT-5A) and various loading forms on the active vibration control are described in the numerical results. 相似文献