高性能可变电容加速度计

本文介绍一种采用硅微加工技术制作的可变电容式加速度传感器.传感器采用了中位面、平面片悬置,气体阻尼和过量程止动.传感器由三块硅基片制成,硅基片采用了阳极粘合技术粘到硅酸盐玻璃镶嵌物上.典型的传感器有效电容为7pF,修正电容为3pF,响应为0.05pF/G,谐振频率为3.4kHz,阻尼临界值为0.7.采用这种传感器的加速度计具有极好的灵敏度和带宽,以及显著的耐冲击性能.     

GX-100型连续测斜仪

本文简要介绍了GX—100型连续测斜仪的工作原理和结构,通过应用实例阐述了仪器所测资料的可信性。最后介绍了仪器的主要技术指标。对仪器进行了初步评价。     

加速度计寻北系统调平补偿技术分析

为了提高寻北系统的测量精度，在研究基于Coriolis效应的加速度计寻北原理的基础上，详细分析了转台调平误差及其噪声干扰对系统测量精度的影响，提出了将两个加速度计按照严格的位置规定安装在高速旋转的转台上，一个用于感应测量地球自转的北向分量，另一个用于转台的解析调平及测量由调平引起的噪声干扰．通过设计，可以降低系统对调平误差的要求，有效地改善系统的信噪比及系统偏差．     

MEMS压阻式三轴加速度传感器的双路循环电桥检测法

A cycle bridge detection method, which uses a piezoresistive triaxial accelerometer, has been described innovatively. This method just uses eight resistors to form a cycle detection bridge, which can detect the signal of the three directions for real time. It breaks the law of the ordinary independent Wheatstone bridge detection method, which uses at least 12 resistors and each four resistors connected as a Wheatstone bridge to detect the output signal from a specific direction. In order to verify the feasibility of this method, the modeling and simulating of the sensor structure have been conducted by ANSYS, then the dual cycle bridge detection method and independent Wheatstone bridge detection method are compared, the result shows that the former method can improve the sensitivity of the sensor effectively. The sensitivity of the x, y-axis used in the former method is two times that of the sensor used in the latter method, and the sensitivity of the z-axis is four times. At the same time, it can also reduce the cross-axis coupling degree of the sensor used in the dual cycle bridge detection method. In addition, a signal amplifier circuit and adder circuit have been provided, Finally, the test result of the ＂eight-beams/mass＂ triaxial accelerometer, which is based on the dual cycle bridge detection method and the related circuits, have been provided. The results of the test and the theoretical analysis are consistent, on the whole.     

一种用于MEMS电容式加速度计的116dB动态范围CMOS读出电路

A high stability in-circuit reprogrammable technique control system for a capacitive MEMS accelerometer is presented. Modulation and demodulation are used to separate the signal from the low frequency noise. A low-noise low-offset charge integrator is employed in this circuit to implement a capacitance-to-voltage converter and minimize the noise and offset. The application-specific integrated circuit （ASIC） is fabricated in a 0.5 /μm one-ploy three-metal CMOS process. The measured results of the proposed circuit show that the noise floor of the ASIC is -116 dBV, the sensitivity of the accelerometer is 66 mV/g with a nonlinearity of 0.5%. The chip occupies 3.5×2.5 mm2 and the current is 3.5 mA.     

基于多元回归模型的捷联惯性测量组件标定技术

应用多元统计分析方法,对捷联惯性测量组件(SIMU)的系统标定技术进行了研究.在考虑加速度计横向灵敏度影响的情况下,将SIMU加速度计组件视为一个整体,提出了SIMU加速度计组件的多元回归模型,并且给出了模型参数的估计公式.多位置标定及静态测试实验结果表明,采用多元回归分析可有效地标定出加速度计组件的刻度系数矩阵、等效安装误差矩阵和等效零位偏置向量.     

用浮动零点法消除温度对SAW加速度计测量准确度的影响

分析了温度漂移对声表面波谐振器(SAWR)及其声表面波振荡器(SAWO)频率特性、以及对SAW加速度计测量准确性的影响,探讨了提高SAW加速度计测量准确度的方法,提出了一种基于浮动零点原理抑制温度共模干扰的双对SAWR加速度计设计方案.本方案不仅通过设置浮动零点SAWR抑制了SAWO频率-温度漂移对SAW加速度计测量准确度的干扰,还在一定程度上降低了对SAWR表面制造工艺的要求.     

压电加速度计的结构与其输出灵敏度的关系

在对压电加速度计输出灵敏度的检测中,我们发现中心压缩式结构压电加速度计的输出灵敏度会随着时间的推移有上下波动的现象,而在剪切型结构的压电加速度计中,它的输出灵敏度变化相对要小得多.围绕这一现象,我们展开了理论分析和数据测试,供讨论.     

不同传感器在桩基完整性检测中的应用

针对速度计能否用于测桩的长期争论 ,本文在比较环境对速度计、加速度计频响和使用效果影响的同时 ,全面比较了这两种传感器在不同桩上的实测结果 ,并根据它们各自存在的优缺点 ,提出了使用这两种传感器的合理建议。