Modeling of a piezoelectric micro-scanner

Micro-scanners have been widely used in many optical applications. The micro-scanner presented in this paper uses multimorph-type bending actuators to tilt a square plate mirror. This paper presents a complete analytical model of the piezoelectric micro-scanner. This theoretical model based on strength of material equations calculates the force generated by the multimorphs on the mirror, the profile of the structure and the angular deflection of the mirror. The proposed model, used to optimize the design of the piezoelectric silicon micro-scanner, is intended for further HDL integration, allowing in this way system level simulation and optimization

Piezoresistive CMOS beams for inertial sensing

This paper presents a preliminary study concerning the use of Front-Side Bulk Micromachining (FSBM) for inertial sensing. When using such a low-cost fabrication approach, the obtained suspended structure do not feature important seismic mass while both CMOS design rules and wet etching do not allow for capacitive detection. Using the standard CMOS polysilicon for piezoresistive detection, obtained results demonstrate that acceptable performance can be reached. In particular, the noise level in polysilicon gauges is low enough to enable a resolution of about 0.5g while sensitivity can be improved by designing dedicated on-chip amplification circuitry. Using both an analytical approach and experimental results, a sensitivity of about 27mV/g is expected for a CMOS-based sensor

Piezoresistive Sensors Development Using Monolithic CMOS MEMS Technology

This paper presents the development of a monolithic CMOS-MEMS platform under the iDesign and SemeMEMS projects with the aim of jointly providing an open access “one-stop-shop” design and prototyping facility for integrated CMOS-MEMS. This work addresses the implementation of a 3-axis accelerometer and a pressure sensor using Semefab’s in-house 2-poly 1-metal CMOS process on a 380/4/15 μm SOI wafer; the membrane and the proof mass being micromachined using double-sided Deep Reactive Ion Etching (DRIE). This monolithic approach promises, in high volume production and using low complexity processes, a dramatic cost reduction over hybrid sensors. Furthermore, the embedded signal conditioning and the low-noise level in polysilicon gauges enables high performance to be achieved by implementing dedicated on-chip amplification and filtering circuitry

Utilisation de Maple V dans l'enseignement de l'automatique

cet article présente une librairie d'automatique développée spécifiquement pour le logiciel de calcul formel Maple V. Cette librairie est utilisée dans un TP qui s'inscrit dans une logique de TP transversaux dont le rôle est de montrer à l'étudiant les liens et inter-dépendances qui existent entre les différentes disciplines de l'E.E.A. Elle est utilisée dans un TP qui fait suite à une série de TP de traitement du signal qui s'effectuent sous Maple V. Ce TP est associé à deux autres travaux pratiques, un en électrotechnique (étude du circuit magnétique du transformateur monophasé), le second en analyse numérique et traitement du signal (numérisation d'un disque microsillon usagé). Cet outil pédagogique (Maple V associé à la librairie d'automatique) permet à l'étudiant de visualiser et de comprendre pas à pas l'influence des différents types de correcteurs sur un asservissement. Il permet, entre autres, de mettre en pratique les techniques de résolutions analytiques apprises en cours sur un exemple réel, avec des équations bien plus complexes

Design of an integrated monolithic 3-axis piezoresistive accelerometer on SOI

This paper discusses the design of an integrated monolithic 3-axis piezoresistive accelerometer on SOI

Noise Analysis of a First-Order Thermal Sigma-Delta Architecture for Convective Accelerometers

International audienceThis paper presents the study of an original closed-loop conditioning approach for fully-integrated convective inertial sensors. The method is applied to an accelerometer manufactured on a standard CMOS technology using an auto-aligned bulk etching step. Using the thermal properties of the sensor, a first order sigma-delta modulator is built. This “electro-physical” modulator realizes an analog-to-digital conversion of the acceleration signal. Besides, the feedback mode of operation improves the sensor overall performance