Publications associées à Vibration and shock reliability of MEMS: modeling and experimental validation

Vibrational NDT with Under-sampled Data through Physics-informed Neural Networks

The vibrational response of solid materials and structural components is substantially governed by their mechanical and geometrical properties. Low-frequency vibrations and modal frequencies are sensitive to global geometrical deviations, while high-freque ...

2023

Damping of flexure blades based on bi-material additive manufacturing

Simon Nessim Henein, Florent Cosandier, Nicolas Blondiaux, Elias Sebastian Klauser, Loïc Benoît Tissot-Daguette, Nikola Kalentics, Lisa Salamin, Florent Alexandre Boudoire

Flexure-based mechanisms have become state-of-the-art solutions for the design of high-precision mechanisms, free from friction wear, backlash, and lubrication. These properties which are necessary for applications in ultraclean or harsh environments, neve ...

2023

An Inertial Uni-Axial Interferometer-Based Accelerometer for Harsh Environments

Mark Edward John Butcher, Gerard Aliana Cervera

For high-impact devices, subsequent vibrations have as much influence on the deterioration of the mechanical structure as the impact itself. To mitigate the consequences of both impacts and resulting vibrations, it is crucial to accurately understand the p ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

A framework for occupancy detection and tracking using floor-vibration signals

Ian Smith, Slah Drira

In sensed buildings, information related to occupant movement helps optimize important func-tionalities such as caregiving, energy management, and security enhancement. Typical sensing approaches for occupant tracking rely on mobile devices and cameras. Th ...

2022

Hybrid Modular Multilevel Converter for Pumped Hydro Storage Applications

Miodrag Basic

Energy balance in a power system must be maintained at all times, regardless of the variations in generation and consumption. Large Pumped Hydro Storage Plants (PHSPs) are introduced to the power system to accumulate the excess of energy during the low dem ...

EPFL2022

Scanning SQUID microscopy in a cryogen-free dilution refrigerator

Philip Johannes Walter Moll, Maja Deborah Bachmann

We report a scanning superconducting quantum interference device (SQUID) microscope in a cryogen-free dilution refrigerator with a base temperature at the sample stage of at least 30 mK. The microscope is rigidly mounted to the mixing chamber plate to opti ...

2021

Novel Generalised Notch Filter for Harmonic Vibration Suppression in Magnetic Bearing Systems

Yves Perriard, Leopoldo Rossini, Guzmán Borque Gallego, Douglas Martins Araujo

Magnetic bearings represent an important alternative to conventional ball bearings for applications that require very low noise and vibrations. The absence of contact and friction between rotor and stator parts, combined with the use of active vibration co ...

2021

Occupancy detection and tracking in buildings using floor-vibration signals

Slah Drira

In sensed buildings, information related to occupant movement helps optimize important functionalities such as security enhancement, energy management, and caregiving. Typical sensing approaches for occupant tracking rely on mobile devices and cameras. The ...

EPFL2020

Crank arrangement for driving a mechanical oscillator

Simon Nessim Henein, Billy Nussbaumer

Crank arrangement (1) for driving a pin-driven two degrees? of freedom mechanical oscillator (5), comprising:- a crank element (7) arranged to be rotationally driven about an axis of rotation (19) by means of a mechanical source of energy (M),- a crank slo ...

2020

Vibration Suppression Through Variable Stiffness and Damping Structural Joints

Gennaro Senatore

This paper introduces a new semi-active strategy for vibration control of truss and frame structures equipped with variable stiffness and damping joints which consist of a shape memory polymer (SMP) core reinforced by an SMP-aramid composite skin. When the ...

2020

Analysis of Free Vibration Characteristics of Tapered Friction Piles in Non-homogeneous Soil Layers

Kwangwoo Lee

This paper presents a new analytical model for estimating the free vibration of tapered friction piles. The governing differential equation for the free vibration of statically axially-loaded piles embedded in non-homogeneous soil is derived. The equation ...

2019

Vibration Mode of MEMS Ultrasonic Sensors on Buckled Diaphragms with Piezoelectric Resonance Frequency Modification

Paul Muralt, Kaoru Yamashita

Vibration mode and resonance frequency of piezoelectric MEMS ultrasonic sensors was investigated on buckled diaphragm structures. The buckling of the diaphragms was introduced intrinsically through residual stress control of the piezoelectric film, and ext ...

IEEE2019

Vibration tests on interconnected timber elements using wood-wood connections

Yves Weinand, Julien Gamerro, Jean-François Bocquet

Vibration tests were performed on 3 large-scale timber slabs using wood-wood connections with a span of 8.1 meters. 10 impulsive vibration tests per specimen were performed to estimate the initial natural frequency. Vibrations were triggered using a hammer ...

2019

Preparation and Decay of a Single Quantum of Vibration at Ambient Conditions

Christophe Marcel Georges Galland, Vivishek Sudhir, Kilian Robert Seibold, Nils Kipfer, Mitchell David Anderson, Santiago Tarrago Velez

A single quantum of excitation of a mechanical oscillator is a textbook example of the principles of quantum physics. But mechanical oscillators, despite their pervasive presence in nature and modem technology, do not genetically exist in an excited Fock s ...

American Physical Society2019

Model-based interpretation of floor vibrations for indoor occupant tracking

Ian Smith, Yves Sylvain Gilles Reuland, Slah Drira

Information regarding occupant flows inside buildings is beneficial for applications such as thermal-load control, market research and security enhancement. Existing methodologies for occupant tracking involve data-driven techniques that rely either on rad ...

2019

Is there a relationship between footstep-impact locations and measured signal characteristics?

Ian Smith, Yves Sylvain Gilles Reuland, Sai Ganesh Sarvotham Pai, Slah Drira

Building utilization can be enhanced by tracking occupants. Non-intrusive tracking of occupants using floor-vibration measurements is beneficial for many smart-building applications such as energy consumption, security enhancement, and care-giving. Also, u ...

ACM2019

Multimode microwave circuit optomechanics as a platform to study coupled quantum harmonic oscillators

Nathan Rafaël Bernier

Harmonic oscillators might be one of the most fundamental entities described by physics. Yet they stay relevant in recent research. The topological properties associated with exceptional points that can occur when two modes interact have generated much int ...

EPFL2019

Research on modal vibration suppression of maglev steel strip based on phase compensator

Yuanping Xu

In the process of vibration suppression of hot galvanized steel strip by using maglev technology, the flexible modal vibration control of steel strip is a challenging problem. Aiming at this problem, this paper proposes a phase compensation control algorit ...

2018

Evidence for structural damping in a high-stress silicon nitride nanobeam and its implications for quantum optomechanics

Tobias Kippenberg, Vivishek Sudhir, Ryan Daniel Schilling, Dalziel Joseph Wilson, Hendrik Schütz, Sergey Fedorov

We resolve the thermal motion of a high-stress silicon nitride nanobeam at frequencies far below its fundamental flexural resonance (3.4 MHz) using cavity-enhanced optical interferometry. Over two decades, the displacement spectrum is well-modeled by that ...

2018

Acoustic emission source detection and wave generation on a working plate using piezoelectric actuators

Xinchang Liu

In modern automated assembly lines, part feeders play an important role to separate and sort parts. Agility and flexibility are required to achieve a good yield for different types of parts. The common working principle is to vibrate a working plate driven ...

EPFL2017