1,578 research outputs found
Electrical method to measure the dynamic behaviour and the quadrature error of a MEMS gyroscope sensor
No full textThe electronics on board of a vibrating MEMS sensor is able to compensate only for small changes in the mechanical characteristics of the
device. Thus, it is of great importance to find an easy and fast way to evaluate the mechanical parameters, such as the resonance frequency and the
damping coefficient, of a MEMS sensor before putting the device on the market [A. Cigada, E. Leo, M. Vanali, Optical and electrical methods to
measure the dynamic behaviour of aMEMSgyroscope sensor, Proceedings of IMECE2005 ASME International Mechanical Engineering Congress
and Exposition 2005, Orlando, Florida, USA [14]]. Moreover, for a vibrating MEMS gyroscope also the quadrature error, i.e. [Y.Y. Bao, C.L. Yung,
Modelling and compensation of quadrature error for silicon MEMS microgyroscope], has to be kept below a given threshold in order to be able to
acurately measure low angular speeds.
Verification tests are usually carried out at the end of the production process, i.e. when the package is complete. Thus, only electrical measurements
are possible. In the present paper, a reliable approach to determine mechanical parameters as well as the quadrature error of the MEMS device
through electrical measurements is proposed and results are compared to more traditional optical measurements
A Case of Children Sexual Abuse: how to improve the presentation of Evidence in the Court
No full text
Optical and electrical methods to measure the dynamic behavior of a MEMS gyroscope sensor
No full textA full characterization of the mechanical parameters for vibrating MEMS sensors is required before integrating the mechanical and the electronic part. This is to verify that the main design specifications are fulfilled before sensors are available on the market. The main goal is to accurately establish the well-working devices in the shortest time. In this paper the electrical method based on the measurement of the GND current is used to satisfy this purpose. To check the validity of the achieved results through this method a comparison is done with those obtained through the widely used optical method based on vibration measurements through by means of a Laser Doppler Vibrometer (LDV). Copyright © 2005 by ASME
Mems gyroscope: electrical method to measure the mechanical parameters and the quadrature error
No full textA full characterization of the mechanical parameters of vibrating MEMS sensors is required before integrating the mechanical and the electronic part. This is to verify that the main design specifications, such as the resonant frequency and the damping coefficient, are fulfilled. Moreover, if we consider not just a vibrating sensor but a vibrating gyroscope, the characterization of the frequency response is not enough, it's important to ensure that the quadrature error is below a fixed threshold. This paper attempts to study both the sensor characterization and the quadrature-error through an electrical approach; in particular, the quadrature error identification is based on the measurement of the ground current originated from the time varying charge, due to the movement of the comb drive actuators. The results achieved with this method are revealed and discussed
Correction to: Size‐Dependent Enforcement, Tax Evasion and Dimensional Trap
No full textThe article “Size‐Dependent Enforcement, Tax Evasion and Dimensional Trap”, written by Raffaella Coppier, Elisabetta Michetti and Luisa Scaccia, was originally published electronically on the publisher’s internet portal on 05 July 2023 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 24 February 2024 to © The Author(s) 2024 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made
Visco-Elastic Modelling of MEMS Inertial Sensors
No full textThe mechanical modelling of MEMS requires the determination of the inertia, of the damping and of the stiffness of the various elements that constitute the device. Although some parameters seem easy to be determined (e.g., the inertia! parameters), at working frequencies typical of MEMS inertial sensors some elements, such as supporting beams, not only contribute to the elasticity of the system but also to its inertia. For what concerns damping, two main pressure levels have to be considered: atmospheric pressure level (from now on called "high pressure," i.e., 105 Pa) and vacuum (from now on called "low pressure," i.e., 26 Pa). At high pressure the mean free path of an air molecule is much smaller than typical MEMS dimensions. Thus, air can be considered as a viscous fluid and two phenomena occur: flow damping and squeeze film damping. These two terms can be evaluated through a simplified Navier-Stokes equation. In vacuum the air cannot be considered as a viscous fluid any more since the mean free path of an air molecule is of the same order of magnitude of typical MEMS dimensions. Thus, the molecular fluid theory must be used to estimate the damping. The present paper shows an approach to pass from a complex FEA model to a lumped parameter model of the considered MEMS inertial sensor at both ambient and low pressure levels that can easily be used during the design or optimisation phases. Although developed and validated for a specific MEMS inertial sensor, the proposed approach is fully general and could be used for any other MEMS device
Modeling The Stiffness And Inertial Characteristics Of Mems' Supporting Beams
No full textMEMS sensors usually work at frequencies well above 1kHz. At these frequencies, supporting beams do not only contribute to the elasticity of the system but also to its inertia. However, the supporting beams' inertia is not equal to any modal mass since excitation frequency is not equal to any eigenfrequency of the supporting beams. Based on a FEA model of the supporting beams it is possible to determine this inertial contribution at any working frequency thus allowing to set up a simple lumped parameter model that correctly reproduces the dynamic behaviour of the device
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