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91.
92.
Christoph Weigel Valeriya Cherkasova Mathias Holz Hai Binh Phi Christian Görner Tenorio Björn Wilbertz Leonard Voßgrag Thomas Fröhlich Steffen Strehle 《Advanced Engineering Materials》2023,25(9):2201873
Ultralow expansion (ULE) glasses are of special interest for temperature stabilized systems for example in precision metrology. Nowadays, ULE materials are mainly used in macroscopic and less in micromechanical systems. Reasons for this are a lack of technologies for parallel fabricating high-quality released microstructures with a high accuracy. As a result, there is a high demand in transferring these materials into miniaturized application examples, realistic system modeling, and the investigation of microscopic material properties. Herein, a technological base for fabricating released micromechanical structures and systems with a structure height above 100 μm in ULE 7972 glass is established. Herein, the main fabrication parameters that are important for the system design and contribute thus to the introduction of titanium silicate as material for glass-based micromechanical systems are discussed. To study the mechanical properties in combination with respective simulation models, microcantilevers are used as basic mechanical elements to evaluate technological parameters and other impact factors. The implemented models allow to predict the micromechanical system properties with a deviation of only ±5% and can thus effectively support the micromechanical system design in an early stage of development. 相似文献
93.
在工程实际应用中,MEMS惯性测量单元的误差来源很多,噪声波动范围很大,温度特性和非线性严重;通过高低温实验,首先,分析系统的误差,建立系统的误差模型,在-30℃~+60℃范围内,进行全温度补偿;然后,分析噪声,根据实际要求,设计数字低通滤波器,对补偿后的数据进行滤波;结果显示,在满足工程实时性与动态特性要求的前提下,陀螺仪的零位补偿精度可以达到±0.03°以内,噪声波动范围可以控制在0.05°以内,加速度计的零位补偿精度达到±0.001g,满足工程实际要求,具有实用性! 相似文献
94.
CHEN KenLe & ZHANG JinWen National Key Laboratory of Micro/Nano Fabrication Technology 《中国科学:信息科学(英文版)》2011,(2)
95.
从工程实际出发,给出了一种基于新型Cortex-M3内核ARM和MEMS惯性传感器的低成本、高性能微型惯性测量单元的结构框架。详细介绍了采用三轴MEMS陀螺、三轴MEMS加速度计和三轴磁阻传感器研制的微惯性测量单元硬件设计方案,分析了陀螺和加速度计的信号噪声,利用均值滤波法对信号进行预处理,对预处理后的信号采用FIR滤波器进行滤波,对陀螺和加速度计进行了标定。该测量单元已应用于某小型无人机的姿态测量,达到预期效果。 相似文献
96.
多传感器数据融合技术已经被广泛应用在多个领域,小波多尺度分解对数据的分析具有独特的优点,小波基的选择对数据融合结果也起着关键的作用.提出一种新的基于多个小波基的数据融合算法,先对含有噪声的传感器信号进行多个不同小波基的多尺度分解,然后对相同小波基分解的信号在多尺度上实施加权数据融合算法,之后进行不同小波基的逆变换得到的重构信号,最后将基于不同小波基的重构信号做最终的融合.实验结果表明:数据融合技术可以从多个方面多个层面以及多种融合原则来考虑,从而融合众多的因素得到最优的结果. 相似文献
97.
The construction of a new generation of MEMS which includes micro-assembly steps in the current microfabrication process is a big challenge. It is necessary to develop new production means named micromanufacturing systems in order to perform these new assembly steps. The classical approach called “top-down” which consists in a functional analysis and a definition of the tasks sequences is insufficient for micromanufacturing systems. Indeed, the technical and physical constraints of the microworld (e.g. the adhesion phenomenon) must be taken into account in order to design reliable micromanufacturing systems. A new method of designing micromanufacturing systems is presented in this paper. Our approach combines the general “top-down” approach with a “bottom-up” approach which takes into account technical constraints. The method enables to build a modular architecture for micromanufacturing systems. In order to obtain this modular architecture, we have devised an original identification technique of modules and an association technique of modules. This work has been used to design the controller of an experimental robotic micro-assembly station. 相似文献
98.
针对目前用于检测汽车制动性能与机动车方向盘转向力-转向角的仪器存在体积庞大、安装复杂、连线繁多、操作技术要求高等特点,提出了采用MEMS型加速度传感器和陀螺传感器为核心检测元件制成的汽车制动性能测试仪器。该测试仪具有便携化、智能化等优点,针对性地解决了以上困扰,为MEMS传感器的应用扩展了新领域。 相似文献
99.
A. BounouhAuthor Vitae H. CamonD. BélièresAuthor Vitae F. Blard F. ZiadéAuthor Vitae 《Computer Standards & Interfaces》2011,33(2):159-164
This work explores MEMS (Micro-Electro-Mechanical Systems) potentialities to fabricate AC voltage references through mechanical-electrical transduction that could be used for high precision electrical metrology and for applications in miniaturized instrumentation. AC voltage reference ranging from 5 V to 90 V have been designed and fabricated using the same Epitaxial Silicon On Insulator (SOI) surface micromachining process allowing an accurate control of both dimensions and material properties. The measured MEMS AC voltage reference values have been found in a good agreement with CoventorWare calculations. These tests structures have also been used to develop the read-out electronics to drive the MEMS. 相似文献
100.
Due to their fast response time miniaturized thermal flow sensors can be applied well for the measurement of instationary gas flow. For some applications, the response time of the sensor must be known with high accuracy. We investigated three methods for response time determination with air: a jump of temperature induced by electric heating, a gas velocity step made by a membrane burst and acoustic phase shifts between sound velocity and sound pressure (standing and traveling waves). The measurements have shown that the response time of thermal flow sensors is a function of flow velocity. For stagnant flow, the thermal response time is about 4.5 ms for our thermal flow sensors. With increasing flow from the heater to the thermopiles, the heat transfer rises. Thus, the response time is faster and decreases to about 1 ms. 相似文献