共查询到20条相似文献,搜索用时 203 毫秒
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氧化铝陶瓷基无线无源压力传感器的高温性能研究 总被引:1,自引:0,他引:1
利用高温烧结陶瓷技术制备了一种基于氧化铝陶瓷的LC谐振式无线无源压力传感器,并通过合理地设计圆柱螺旋天线以及隔热结构,实现了该传感器在高温环境中的无线耦合测试。研究了传感器在不同温度下的阻抗频率特性,分析并探讨了传感器的高温性能。测试结果表明,在29℃(室温)至700℃的温度范围内,测试天线端的最高瞬时温度为188.4℃,保证了传感器高温测试的可靠性。谐振频率对温度的平均变化量为1.314 kHz/℃,两次重复性测试的相对变化量为3.81%,重复性较好。该压力传感器可应用于高温恶劣环境下的压力测试,其高温性能的研究为压力信号的准确读取奠定了良好的基础。 相似文献
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《电子制作.电脑维护与应用》2017,(6)
碳基复合材料只从在发现之后,就得到了人们广泛关注,其中以石墨烯作为典型代表。碳基复合材料自身具有较多特殊性能,例如机械强度较高、热稳定性能良好。正式由于这些特殊性能让碳基复合材料在传感器、纳米电子器件等领域上广泛应用,具有良好发展前景。本文就对碳基复合材料中的石墨烯作为研究对象,希望能够对碳基复合材料制备及其电化学电极全面了解。 相似文献
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电磁激励谐振式MEMS压力传感器闭环控制研究 总被引:1,自引:0,他引:1
在谐振器动力学分析的基础上,系统地比较了谐振式压力传感器检测速度谐振频率和检测位移谐振频率的优缺点.设计出一种零相移的电磁激励谐振式MEMS压力传感器闭环控制系统,该系统利用检测速度谐振频率提高传感器的信号检测稳定性,并且控制电路无需移相环节即可保证传感器在工作频率范围内实现稳定可靠的闭环自激.实验结果表明,采用该闭环控制系统的传感器具有较高的稳定性,传感器长时漂移低于0.025%F.S.,在10 hPa~1 050 hPa范围内非线性度为0.06%. 相似文献
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微谐振式压力传感器尺寸小、重量轻、精度高并具有效字输出,在航空航天等领域有着广阔的应用前景.然而由于微机械加工工艺的限制,复杂结构的制作存在很多困难,因而为实现高灵敏度压力测量,微谐振式压力传感器的结构设计就显得尤为重要,因此提出一种新型硅岛式谐振梁支撑结构,它利用硅薄膜作为典型的一次敏感元件,并在其上表面中央部位设计了两个硅岛凸起平台,用以固定硅谐振梁,并通过有限元软件ANSYS进行仿真.分析结果表明,在一定量程内,该结构能有效提高谐振梁内的应力放大倍数,进而提高微压力传感器的灵敏度. 相似文献
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设计并制备了由黑磷烯/氧化石墨烯双层材料为介质层的电容式柔性压力传感器,该传感器结构以ITO为电容上下极板,PET为柔性基底,并对该传感器进行了系统的性能测试与分析。着重研究了该传感器在不同压力量程内的灵敏度,进而分析了其温度漂移特性。测试结果表明,以黑磷烯/氧化石墨烯薄膜为双介质层的电容式柔性压力传感器在0~3.12 kPa压力量程内灵敏度可达到1.60 kPa-1。同时,对该传感器和以氧化石墨烯薄膜为单介质层的传感器进行了弯曲应变性能的对照实验,可知具有双介质层的传感器结构能够显著提高传感器的输出特性。 相似文献
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Huichao Shi Shangchun Fan Weiwei Xing Cheng Li Jinhao Sun Zhongwu Jing 《Microsystem Technologies》2013,19(7):979-987
This paper proposes a slit-resonant beam based on the double clamped resonant beam theory of silicon micro-machined resonant pressure sensors. The slit structure can enhance surface alternating stress in the root area of beam while vibrating. Finite element method (FEM) is applied to calculate the stress concentration magnification, and we carry out a computational study of the effects of size and location of slit structure in terms of mechanical properties of resonant beam, such as stress concentration on resonant beam and natural frequency of resonant beam, as well as sensing performance, such as resonant beam amplitude sensitivity. Our simulations show that the slit structure could strengthen the stress concentration and increase the amplitude detection sensitivity, and the variations of these parameters can substantially influence the performance of slit structure. The research of stress concentration, caused by silt structure, could provide reference for further optimization and design for the resonant beam. 相似文献
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石墨烯因其独特的结构和特性,具有广泛的应用前景.采用分子动力学的方法模拟石墨烯被硅探针压变形后弯曲振动的动力学过程,探讨了石墨烯纳米带的尺寸和温度对石墨烯纳米带谐振特性的影响.模拟结果表明,石墨烯纳米带的谐振频率随着石墨烯纳米带的长度、宽度、层数(厚度)以及温度变化.其中宽度、厚度和温度对石墨烯纳米带谐振频率的影响较小,影响石墨烯纳米带谐振频率的主要因素是长度. 相似文献
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Xu Zhang 《Computers & Fluids》2009,38(2):340-346
Despite the importance of wall shear stress measurements in both fundamental and applied fluid dynamic problems, sensors for this application suffer from several shortcomings. A new class of wall shear stress sensor concept that addresses these shortcomings is studied numerically. The properties of a dynamic resonant shear stress sensor are determined using a specially-developed two-dimensional unsteady boundary layer code and a commercially available three-dimensional fluid model. Several characteristics of the sensors are determined using these models including: static sensitivities with and without pressure gradients, sensor design parameter effects. These results indicate that low amplitude, high resonant frequency operation associated with small sensors will have optimum performance. These results also suggest that a MEMS implementation of this sensor should provide the capability of measuring wall shear stress fluctuations in turbulent flows. 相似文献
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Certain problems arising in operation of pressure sensors used in rockets and aircrafts are considered. The role and position of thin-film tensoresistive pressure sensors (PRPS) are discussed; these sensors are based on thin-film nano-and microelectromechanical
systems. The basic research directions in the field of PRPS are analyzed and presented. The relevance of solving the problem
to improve the accuracy and performance characteristics of the sensors and sensing devices (to the level of best-in-class
products) is shown; certain ways to solve it are proposed. The basic research directions in the field of PRPS are identified
allowing to design the pressure sensors being stable to external influence of nonstationary temperatures and increased vibroaccelerations. 相似文献
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MEMS谐振式传感器具有精度高、准数字输出、抗干扰能力强等特点,高精度压力传感器、应力传感器等多采用谐振式工作原理.频率温度系数补偿是实现高精度谐振式传感器的关键技术.通过实验研究了利用重掺杂改善硅频率温度系数的技术.实验表明:P型掺杂浓度达到7 × 1019/cm3 时,〈110〉晶向频率温度系数降低到-11. 68 ×10-6/K;N型掺杂浓度达到6 ×1019/cm3 时,〈100〉晶向谐振频率是温度的二次函数,在80℃左右频率温度系数有过零点.首次实验演示了利用低功耗加热控制结合N型重掺杂,当环境温度由30℃变化到40℃时,谐振频率温度漂移仅为1. 13 ×10-7/℃.利用该技术可实现超高温度稳定性的谐振式传感器. 相似文献
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M. Maroufi Sh. Zihajehzadeh M. Shamshirsaz A. H. Rezaie 《Microsystem Technologies》2011,17(4):575-583
Ensuring desirable performance for piezoelectric microcantilever sensors constitutes a crucial research subject particularly
for the applications such as detection of biochemical entities, virus particles or human biomarkers. However, these sensors’
performance may be affected by the environmental conditions such as temperature variation, and/or the uncertainty in the material
properties. The objective of this study is to explore Young modulus uncertainty of microcantilever’s structural layer, thermo-mechanical
and geometrical temperature dependency effects, on the natural frequency, bias and sensitivity of microcantilever mass sensors.
These effects have been investigated for different sensor lengths and resonant modes. Also, a temperature compensation method
which omits the need for bulky non-contact thermometers or fabrication of built-in temperature sensor has been proposed. As
theoretical model, Euler–Bernoulli beam theory has been employed and solved by Galerkin expansion procedure. Using this model,
it is demonstrated that the sensitivity of microcantilever sensor decreases with increasing the added mass. The microcantilever
sensor sensitivity operating at the second resonant mode has been improved almost five times comparing to the first mode sensitivity
regardless of microcantilever length. The simulation results show that temperature variation causes thermal frequency shift
which in turn introduces a significant mass bias far beyond the sensors’ minimum detectable mass. This mass bias is constant
for a given microcantilever in its first and second resonant mode. Additionally, the effect of temperature variation on the
sensitivity of the given mass sensors is negligible. However, it has been shown that the variations in sensors sensitivity
due to uncertainty of Young modulus remain constant for different lengths and two resonant modes of the microcantilever sensor. 相似文献
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近年来,超多目标优化逐渐成为多目标优化研究的热点之一,由于超多目标优化问题具有难以寻优的高维目标空间,其研究颇有挑战性,因此受到广泛关注.现有综述性文献通常只是针对某个特定方面,缺乏系统性考察.鉴于此,首先从问题定义出发,综合考虑超多目标优化问题范畴,进行超多目标优化问题的概念辨析;其次通过对近些年的相关文献整理,系统分析超多目标优化问题进展并对其中部分经典方法加以介绍,通过对基准测试函数和性能指标的说明,围绕超多目标优化研究方法展开综合性论述;接着选取5个典型的超多目标进化算法,在2组基准测试函数和4个实际问题上分别展开仿真实验,通过性能指标和非参数检验对不同类别的算法进行理论分析;最后在明确超多目标优化研究领域的若干前沿问题的基础上,对今后的研究工作进行展望. 相似文献
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根据LC谐振传感器互感耦合系统的理论模型,设计了一种LC谐振传感器信号检测系统。该系统包括模拟部分、数字部分以及解算方法。模拟部分是通过混频器提取谐振信息,再用低通滤波器( LPF)直流化输出信号以方便数据采集。数字部分是完成信号采集及传给上位机处理。解算方法是通过同步模拟部分的线性扫频源与数字部分的数据采集,实现从携带谐振信息的直流信号中获取谐振频率。实验结果表明:该系统能够完整获得LC谐振传感器的测试信号,其性能稳定,测量精度高,谐振频率测量误差小于3.5%。该系统有望运用于LC传感器信号无线测量的领域。 相似文献
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基于谐振式硅微结构压力传感器幅、相频率特性的分析,利用北京航空航天大学微传感器实验室研制的谐振式硅微结构传感器开环测试系统的测试实验结果和Matlab实验数据处理与拟和分析计算,建立了微传感器的二阶模型.该模型排除了未知相位延迟的影响,从幅值和相位混合的测试数据中精确计算出谐振频率、品质因数以及相位特性,为闭环测试系统的研制提供了依据. 相似文献