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INTRODUCTIONAsweknow ,thecomputationalpiezoelectricdynamicequationsforhighfrequencyacousticwavepropagationswereoriginallyexpandedfromthegeneralcomputationalstructuralmechanics,andthefiniteelementmethods(FEM)initiallyfromaerospaceandcivilengineering .The… 相似文献
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为了消除压电陶瓷的迟滞、蠕变等非线性对定位精度的影响 ,采用了非线性PID控制算法来实现微定位工作台的实时控制。利用跟踪微分器对信号进行跟踪并得到其微分信号 ,提高了控制系统的鲁棒性。通过计算机仿真 ,验证了所设计的微定位工作台的特性和闭环控制算法的有效性 相似文献
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In piezoelectric problems, the form of the general solution is dependent on the eigenvalues of the material. The singular
stress field and electrical displacement field near the interface edge were deduced in this study. The results showed that
the stress field and the electrical displacement field have the same singularity; and that the singularity depends not only
on the mechanical properties and shape of the interface edge, but also on the piezoelectric properties of the composite material.
Project (19972060) supported by Natural Science Foundation of China. 相似文献
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INTRODUCTIONPiezoelectricceramicmaterialshavemanyapplicationsinmoderntechnologiesbecauseoftheirexcellentpiezoelectricproperties.Butcracksarisingfromtheirintrinsicbrittlenessof tencausepiezoelectriccomponentsfailure .Studyofwhatcausesthisrequirestheoret… 相似文献
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利用新型压电薄膜传感器输出信号随冲击大小而变化的特性,通过Soc单片机系统,实现了对击打力、击打速度和反应度的准确测量;不但能通过液晶显示器显示测值,而且通过软件实现了对训练机功能的菜单控制;通过语音电路和音箱实现了对测值的语音输出和对训练者的语音提示。经多家武校和跆拳道馆的试用,证明多功能搏击训练机稳定可靠,功能齐全,且造价低廉。介绍了多功能搏击训练机测量原理、结构和软件功能。 相似文献
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We propose a new approach to obtain ultra-high piezoelectric coefficients that can be infinitely large theoretically, where ferroelectrics with strain-sensitive Curie temperature are necessary. We show the first-principles plus Monte Carlo simulation evidence that many hydrogen-bonded ferroelectrics (e.g. organic PhMDA) can be ideal candidates, which are also flexible and lead-free. Owing to the specific features of hydrogen bonding, their proton hopping barrier will drastically increase with prolonged proton transfer distance, while their hydrogen-bonded network can be easily compressed or stretched due to softness of hydrogen bonds. Their barriers as well as the Curie temperature can be approximately doubled upon a tensile strain as low as 2%. Their Curie temperature can be tuned exactly to room temperature by fixing a strain in one direction, and in another direction, an unprecedented ultra-high piezoelectric coefficient of 2058 pC/N can be obtained. This value is even underestimated and can be greatly enhanced when applying a smaller strain. Aside from sensors, they can also be utilized for converting either mechanical or thermal energies into electrical energies due to high pyroelectric coefficients. 相似文献
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利用压电换能器等效电路网络分析法,计算了36°Y切LN/PM声光器件换能器的归一化电输入阻抗|Zj|随归一化频率f/f0的变化值;绘出了|Zj|-f/f0关系立体图;得出器件的输入阻抗是随频率变化的复杂复数函数且在不同工作频率段均呈现容抗特性的结论. 相似文献
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基于全息二次曝光法的压电陶瓷逆压电效应测定 总被引:1,自引:0,他引:1
论述二次曝光全息干涉计量的原理,分析干涉条纹与物体变形量的关系.利用全息二次曝光法对压电陶瓷的逆压电效应进行测定.实验结果与相关文献一致,表明该方法用于测定材料的逆压电效应是可行的. 相似文献
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径向模式振动的压电变压器是由硬的压电材料建成,具有较高的机械品质因数Qm,它是沿厚度方向极化。首先根据压电变压器等效电路模型图建立压电变压器的动力学模型,根据各个负载电阻,测定的电压升压比,输出功率,效率方面的电性能,得出电压升压比与负载电阻成比例地增大,之后对不同厚度的压电变压器进行Comsol仿真,对比得出最优的压电变压器。后通过MATLAB仿真得出电阻最佳时,效率达到最大可以达到90%,升压比为1.5,对这些结果进行比较,从等效电路的分析计算,得出他们有很高的效率和稳定性,可以解决原有卫星推进器效率低、不稳定的状况。 相似文献