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1

Electroacoustic Analysis of a Controlled Damping Planar CMOS-MEMS Electrodynamic Microphone

Tounsi F., Mezghani B., Rufer L., Masmoudi M.

Archives of Acoustics

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2015

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Vol. 40, No. 4

527--537

EN

This paper gives a detailed electroacoustic study of a new generation of monolithic CMOS micromachined electrodynamic microphone, made with standard CMOS technology. The monolithic integration of the mechanical sensor with the electronics using a standard CMOS process is respected in the design, which presents the advantage of being inexpensive while having satisfactory performance. The MEMS microphone structure consists mainly of two planar inductors which occupy separate regions on substrate. One inductor is fixed; the other can exercise out-off plane movement. Firstly, we detail the process flow, which is used to fabricate our monolithic microphone. Subsequently, using the analogy between the three different physical domains, a detailed electro-mechanical-acoustic analogical analysis has been performed in order to model both frequency response and sensitivity of the microphone. Finally, we show that the theoretical microphone sensitivity is maximal for a constant vertical position of the diaphragm relative to the substrate, which means the distance between the outer and the inner inductor. The pressure sensitivity, which is found to be of the order of a few tens of μV/Pa, is flat within a bandwidth from 50 Hz to 5 kHz.

2

Low-noise micro-power chopper amplifier for MEMS gas sensor

Nebhen J., Meillere S., Masmoudi M., Seguin J.-L., Barthelemy H., Aguir K.

International Journal of Microelectronics and Computer Science

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2011

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Vol. 2, nr 4

146-155

EN

In this paper, a low-noise, low-power and low voltage Chopper Stabilized CMOS Amplifier (CHS-A) is presented and simulated using transistor model parameters of the AMS 0.35 μm CMOS process. This CHS-A is dedicated to high resistive gas sensor detection. The proposed CHS-A using Chopper Stabilization technique (CHS) exhibits an equivalent input referred noise of only 0.194 nV/√Hz for a chopping frequency of 210 kHz under ۫.25 V supply voltage and 26.5 dB voltage gain. The inband PSRR is above 90 and the CMRK exceeds 120 dB. At the same simulation condition, the total power consumption is 5 μW only.

3

A New Design of a Robot Prototype for Intelligent Navigation and Parallel Parking

Abdelmoula Ch., Chaari F., Masmoudi M.

Journal of Automation Mobile Robotics and Intelligent Systems

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2009

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Vol. 3, No. 2

47-58

EN

Nowadays, the design of industrial vehicles and movable cars is based on the automation of their different tasks, which are currently handled by humans. These tasks, such as maneuvering robots in complex environments, require high level of precision that cannot be guaranteed by humans. Manual operations are likely to produce errors of computation and optimization of navigation and manoeuvre (left, right, veering…). In this paper, a novel prototype of a well-structured robot for intelligent navigation and parallel parking applications is presented. The robot have two axels, the front one is composed of two wheels that are manoeuvred by a stepper motor, and a pinion rack system for controlling the rotation of the wheels, and also the orientation of the robot. The driving wheels are mounted in the rear axle of the robot and are commanded by two DC motors. The design allows modification of the robot structural components whenever required. In addition to the mechanical components, the prototype is equipped with a DC power supply, three infra-red sensors, one ultrasound sensor, and control modules composed of an FPGA card, microcontroller card and two cards which are responsible for commanding actuators. The parameters of the mechanical and electronics components are optimised to perform multiple tasks for training and instruction applications. A mathematical model that describes the dynamics of the robot prototype is also developed. Simulation, experimental and theoretical investigations were carried out consisting in navigation and parallel parking manoeuvres. It was confirmed that the experimental and theoretical results agree well in both applications.

4

Crack detection by the topological gradient method

Amstutz S., Horchani I., Masmoudi M.

Control and Cybernetics

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2005

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Vol. 34, no 1

81-101

EN

The topological sensitivity analysis consists in studying the behavior of a shape functional when modifying the topology of the domain. In general, the perturbation under consideration is the creation of a small hole. In this paper, the topological asymptotic expansion is obtained for the Laplace equation with respect to the insertion of a short crack inside a plane domain. This result is illustrated by some numerical experiments in the context of crack detection.