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排序方式: 共有1224条查询结果,搜索用时 109 毫秒
1.
针对应用领域中判断水平面及水平面夹角的问题,设计一种倾斜姿态角传感器。把MEMS加速度计SCA103T-D04与C8051F47单片机组合在一起,对MEMS加速度计输出信号进行调理和AD采集,单片机C8051F047完成数据分析和温度补偿,并通过CAN总线通讯接口和RS232通讯接口输出倾斜角度值,输出周期为200 ms。该倾斜姿态角传感器测量精度为0.03°,测量范围为–6°~6°,具有体积小、重量轻、精度高、温度适应范围宽的特性,可广泛应用于建筑、道路、桥梁及军用设备等领域。 相似文献
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提出了用声表面波滤波器测知加速度方向和大小的原理和方法,研究了电容器中的静电吸引力对加速度计敏感质量块的位置稳定作用,以及用它扩大悬臂梁式加速度计量程的原理.还对静电力扩程之后,加速度计测量值的校准、计量标定等问题进行了有益地探讨,针对电容器静电力的非线性扩程特点,提出了查询表式的在线实时测量换算读值方案. 相似文献
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According to the diversity of the pipeline vibration and unicity of vortex signal in direction, a new idea is proposed to distinguish the vortex signal from the vibration interference by the directional character. This idea is applied to improve the anti-vibration performance of vortex flow-meter by a new probe structure based on three-axis accelerometer. Then model analysis is used to optimize the material, and the harmonic response analysis is applied to optimize the shape of probe tip. Finally, experiment is carried out to compare the anti-vibration performance of the traditional piezoelectric vortex probe and the new design. Experimental results show that new probe can accurately distinguish vortex signal from the vibration interference according to the directional character of signal. And its anti-vibration performance is superior to the traditional piezoelectric vortex probe. 相似文献
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The design process of heterogeneous systems containing electro-mechanical components and electronic circuits involves expert knowledge, methods, and tools from different engineering domains. Cost-efficient research and development of such heterogeneous systems requires a systematic design flow without gaps. A contribution towards this global goal is presented in this article. A development and synthesis tool for one-dimensional accelerometer MEMS has been implemented, calculating sensor solutions and generating the models and layouts required for a hierarchical design flow in an automatic, module-based approach. Utilizing this flow, different accelerometers have been designed, manufactured, and characterized. A dedicated readout ASIC was developed to validate their dynamic behaviour. 相似文献
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It is widely known that in the primary calibration of accelerometers by using a laser interferometer, a device under test (DUT) and the laser interferometer should measure vibration at the same reference position. However, this is not applicable to single-ended accelerometers because of the limitation of their design. One way of overcoming this limitation is to measure the vibration at several positions on the exciter table surface which connects DUT to a vibration exciter. However this can present the effects of rocking motions of the exciter. Although the motions of vibration exciters are presented in several studied, the different model of exciters might have different characteristics. This paper aims to study the motions of an air-bearing exciter (model 2911) used at National Institute of Metrology (Thailand) in order to expose their characteristics, their effects on the calibration results and the measurement errors due to these effects. The motions of the exciter are shown in terms of magnitude and phase shift distributions of sensitivities. These can be obtained by measuring the magnitudes and phase shifts at several positions on the exciter surface. The effects of exciter motions are measured in terms of how much the magnitudes and phase shifts at each measured positions deviate from the average values. To illustrate these effects, parametric studies were conducted. The influences of four parameters, i.e. the angular positions of the laser points, the distance of the laser positions from the centre of the exciter surface, the number of measured positions to be averaged and the mass loading effect, were examined experimentally. The frequency of interest is between 10 Hz and 15 kHz. 相似文献
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《Measurement》2016
In order to set integrated procedures involving geotechnical and structural aspects finalized to buildings diagnostics, uncertainty aspects are discussed concerning three-axis accelerometers and inclinometers for a distributed sensor network. This network allows to operate in a selective manner, preferring the most critical situations. To this aim, the main aspects affecting the measurement uncertainty of sensors to be used for building diagnostic should be known. As the firstly step of the uncertainty evaluation procedure, we focused on the calibration of sensors used for the task. The requirement of low cost and complexity of sensors and test benches was considered. Experimental results show that satisfactory calibration accuracy could be achieved, also for the low frequency range, 0–10 Hz. Systematic errors are minimized and main parameters affecting uncertainty are identified, such as: the motion positioning of the accelerometer with respect to the vertical axis, the imposed motion law, the parameter used as the reference and, finally, the real radial positioning of the sensor. Requirements to be satisfied by the sensor are also analysed. 相似文献
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