The technical achievement is the acoustical characterization of an e-motor in run-up conditions. The directivity of the sources around the motor has been deeply studied.
The iterative Bayesian Focusing method combined with refined acoustical transfer functions has been industrially applied. Confidence intervals about the sound power have been also estimated.
This paper has been supported by the national project FUI LUG2. This study has been extracted from a larger study made with Renault. The measurements were carried out on the VibraTec test bench.En savoir plus
To answer sound disturbance issues due to deep sea underwater mining prospecting, MicrodB studies the possibility to set up an underwater acoustic source localization and quantification monitoring system in deep water (700 m).
After a first simulation step to point out the best acoustic array geometry for this problem, it was built and then tested in shallow water in 2018. Results presented at Oceans 2019 show the agreement between simulation and experimental data validating the whole conception of this array.
This work was realized within the framework of FUI 22 Abysound project, funded by Pôle Méditerranée and Banque Publique d’Investissement whose partners are Naval Group, OSEAN SAS, Semantic TS, Ifremer, Gipsa-Lab, LMA and LSIS.En savoir plus
Based on multi-arrays measurement, the Bayesian Focusing has been applied to measure the Transmission Loss (TL) on a 3D mesh representing the real geometry of an automotive Dashboard.
New Bayesian priors have been tested to enforce the spatial sparsity of the sound sources. As the sources are stationary in the frequency domain, a spatial prior defined on a large range of frequencies has been applied.
The work has been done with Trèves Group.
This research was supported by the LUG2 project funded by the Région Auvergne Rhône-Alpes and the BPI France (grant FUI22).En savoir plus
Sound source localization using microphone arrays is largely applied in industrial engineering to diagnose acoustic issues appearing in complex machines. Over the past 30 years, a large number of methods have been developed to improve the source identification procedure.
Bayesian Focusing can generalize these methods by automatically calculating the optimal functions based on the geometrical set-up. In addition, probabilistic acoustic inverse problem solving offers the possibility to introduce prior knowledge of the source, noise and propagation model.
MicrodB is a precursor in this technology thanks to its collaboration with the INSA Lyon
The use of Bayesian Focusing capabilities to extract source characteristics (directivity, coherence, sound power) greatly improves sound source identification in industrial applications.
This will be documented at the ISMA conference in Leuven on September 17th to 19th.En savoir plus
Between 25th and 29th June 2018 will be held the 24th AIAA/CEAS Aeroacoustics Conference in Atlanta.
It is certainly one of the most famous scientific conferences in the field of flow induced acoustics. MicrodB is proudly contributing to a research paper, together with Ecole Centrale de Lyon, University of Sherbrooke and Safran Aircraft Engines. The work, entitled ‘Broadband Airfoil-Noise Source Localization by Microphone Arrays and Modeling of a Swept Free-Tip Blade’ will be presented by Gyuzel Yakhina.
It is the occasion to apply advanced microphone array techniques in complex wind tunnel configurations.En savoir plus
MicrodB, INSA Lyon and CNRS will present a paper entitled « SENSITIVITY ANALYSIS OF ACOUSTIC INVERSE PROBLEMS » at NOVEM 2018 Ibiza from 7th to the 9th May
The characterisation of an acoustic source is achieved by retro-propagating the acoustic field measured with a microphone array to a mesh of the surface of interest. This latter step is performed by solving an inverse problem. Such inverse problems are built on the basis of a forward model prone to uncertainties arising from the physics of the experiment.
Assessing the effects of these uncertainties on the resolution of the inverse problem represents a challenge. This paper introduces a practical solution to measure these effects by conducting a sensitivity analysis. The sensitivity analysis method applied here provides a mean to identify and rank the main sources of uncertainty through the estimation of sensitivity indices. Two inverse methods are investigated for the reconstruction of a monopole source: Beamforming and Bayesian focusing. The propagation of uncertainties is carried on numerically. The consistency between the real experiment and its numerical approximation is assessed by means of a small batch of measurements performed in a semi-anechoic chamber.En savoir plus
Managing MEMs microphone calibration – MicrodB will share its findings at the 14th French Acoustic Congress in Le Havre from April 23rd to 27th
The democratization of information technologies and communication (ICTS) offers new possibilities for acoustic metrology, and more specifically methods implicating a large number of microphones. Digital MEMs sensors and embedded ARM FPGA processors provide a new solution for these situations, increasing performance while reducing implementation costs.
However, the integration of these technologies, which are not intended for metrology, requires rigorous calibration to identify and correct the intrinsic frequency response of the MEMs welded on an electronic board (PCB).En savoir plus
If you are interested in meeting Vibratec at TRA 2018 in Vienna, the 17th and 18th of April, Lucille LAMOTTE will participate in the oral presentations and bilateral meetings organized in parallel by ETNA2020 Transport Networking and Brokerage Event focusing on the Horizon H2020 ‘Smart green and integrated Transport’ calls 2018-2020.
As an SME used to working on R&D projects on both national and international levels, we know the importance of finding the right partners for each project. ETNA is the perfect opportunity to broaden our network and increase visibility for potential European partners.En savoir plus
Innovate with MicrodB ! We will be at the Smart Industries event during the Global Industrie fair in Paris from 27 to 30 March
MicrodB and VibraTec were chosen to represent the Auvergne-Rhone-Alpes region as SME with innovative products & services (predictive maintenance, innovative sensors, digital twins, etc).
Lucille Lamotte and Agnès Gerphagnon will present the group’s latest innovations, including the LMS SoundCamera developed by MicrodB and our predictive maintenance SmartSolutions connected, autonomous sensors.
The Global Industrie fair focuses on the Industry of the Future and brings together stakeholders from the entire manufacturing ecosystem and all industry sectors. It is backed by President Macron, the French government and the Industry of the Future Alliance (AIF). From March 27th to the 30th, almost 3 thousand exhibitors will welcome over 50 thousand visitors.En savoir plus
MicrodB and Siemens Industry Software will present a paper entitled “Sound Source Localization Analysis in the Combustion Cycle of ICE Powertrains” at DAGA 2018 in Munich from the 19th to the 22nd of March
In order to help engine manufacturers optimize powertrain noise, MicrodB and Siemens Industry Software NV propose Sound source localization techniques supported by advanced processing.
The application of a cyclic Wiener filter relying on reference cylinder pressure sensors effectively separates microphone array data into combustion and mechanical components. Sound source localization of these separated components makes it possible to identify the main sources related to combustion and mechanical noise.
The powertrain noise – mechanical and/or combustion – can also be analyzed in segments of the combustion cycle itself. This requires pre-processing in the angle domain, after which sound source localization is applied on angular ranges.
During the presentation those two processes will be described and applied to engine test bench experimental data.En savoir plus