numerical comp.

Numerical computing
Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 07/10/13
  • Minor correction: 07/10/13

OpenMEEG : resolution of forward problems in electroencephalography and magnetoencephalography

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 2.1 - 17/08/2011
  • License(s): CeCILL-B
  • Status: stable release
  • Support: maintained, ongoing development
  • Designer(s): Theodore Papadopoulo
  • Contact designer(s): Theodore.Papadopoulo @ inria.fr
  • Laboratory, service:

 

General software features

OpenMEEG, now developed by the Athena project (INRIA Sophia Antipolis), is dedicated essentially to the resolution of the forward MEG (magneto-encephalography) and EEG (electroencephalography) problems. For this purpose, it uses a finite surface element method (BEM) that involves at the same time surface potentials and normal currents, which yields symmetrical matrices unlike classical approaches. This approach yields more precise results as well.

Though developed essentially for problems related to brain, OpenMEEG can also be used in other contexts such as electrocardiography, nerve simulation or electrical propagation in the cochlea.

OpenMEEG starts from a geometric-physical description of the head as nested surfaces in the form of meshes (interfaces between head tissues) and of conductivities of the surface delimited tissues. Then, with a description of EEG and/or MEG capture devices, it yields a leadfield, i.e., the transfer matrix modelizing the linear relation from sources to capture devices.

OpenMEEG is written entirely in C++, but is usable from Matlab or Python. It is used/integrated in a few software suites for analysis of signals in the brain, such as Brainstorm, Fieldtrip or SPM, ...

Context in which the software is used

Research in medical imagery.

Publications related to the software
  • A. Gramfort, T. Papadopoulo, E. Olivi, M. Clerc. OpenMEEG: opensource software for quasistatic bioelectromagnetics, BioMedical Engineering OnLine 45:9, 2010.

  • Kybic J., Clerc M., Abboud T., Faugeras O., Keriven R., Papadopoulo T., A common formalism for the integral formulations of the forward EEG problem. IEEE Transactions on Medical Imaging, 24:12-28, 2005.

  • See also the software documentation: http://www-sop.inria.fr/athena/software/OpenMEEG/i...

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 22/09/13
  • Minor correction: 22/09/13

Ibex : C++ numerical library based on interval arithmetic and constraint programming

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 2.0.9 - 28/08/2013
  • License(s): LGPL - v3
  • Status: beta release
  • Support: maintained, ongoing development
  • Designer(s): Ibex team
  • Contact designer(s): gilles.chabert @ mines-nantes.fr
  • Laboratory, service: Universidad TĂ©cnica Federico Santa MarĂ­a (Chile)

 

General software features

This C++ library can be used to solve a variety of problems that can be formulated roughly as:

Find a reliable characterization with boxes (Cartesian product of intervals) of sets implicitely defined by constraints.

Where 'reliable' means that all sources of uncertainty should be taken into account, including:

  • approximation of real numbers by floating-point numbers,
  • round-off errors,
  • truncation linearization,
  • model parameter uncertainty,
  • measurement noise,
  • ...
Context in which the software is used

Tool for research in constraint programming.

Publications related to the software
Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 19/09/13
  • Minor correction: 19/09/13
  • Index card author: Eric Hivon (IAP)
  • Theme leader : Dirk Hoffmann (Centre de Physique des Particules de Marseille (CPPM-IN2P3))

HEALPix : data analysis, simulation and visualisation on the sphere

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 3.11 - April 2013
  • License(s): GPL - GPLv2
  • Status: stable release
  • Support: maintained, ongoing development
  • Designer(s): Eric Hivon; Martin Reinecke; Krzysztof M. Gorski; Anthony J. Banday; Benjamin D. Wandelt; Emmanuel Joliet; William O'Mullane; Cyrille Rosset; Andrea Zonca
  • Contact designer(s): hivon at iap.fr
  • Laboratory, service: MPA (Garching, Allemagne), Caltech (Pasadena, CA,Etats-Unis), TAC (Copenhague, Danemark), ESAC (Madrid, Espagne), JPL (Pasadena, CA, Etats-Unis), ESO (Garching, Allemagne)

 

General software features

The HEALPix software implements the HEALPix (Hierarchical Equal Area iso-Latitude Pixelation) pixelation of the sphere. Initially developed for the simulation and analysis of ESA Planck satellite observations (dedicated to the study of the Cosmic Microwave Background (CMB) anisotropies, whose first results were delivered in March 2013), this software and its pixelation algorithm have become standard tools in the simulation and analysis of data on the sphere, including the NASA WMAP satellite, also dedicated to CMB observation, and the Pierre Auger ground based observatory for high energy cosmic rays, and are used for other astrophysical and geological studies.

Main features of the pixelation

At a given resolution, all HEALPix pixels have the same surface area, even if their shape varies slightly. Thanks to the hierarchical feature of the pixelation, upgrading its resolution to the next level simply amounts to divide each pixel into four sub-pixel of the same area. This allows quick and efficient upgrading and downgrading operations of existing maps.

Since the pixels are regularly spaced on iso-latitude rings, Spherical Harmonics can be computed very efficiently. The synthesis or analysis up to multipole Lmax  of a spherical data set containing Npix pixels is reduced from    Npix Lmax2   to   Npix½ Lmax2  compared to non iso-latitude pixelation.

Features of the software package

The represents data on the sphere, and enables analysis or simulation of these maps in (scalar or spin-weighted) Spherical Harmonics, as well as various kinds of statistical analyses and processing. Portable FITS files are used for input and output. The list of available functions includes:

  • generation of random maps (gaussian or not) from an arbitrary angular power spectrum,
  • computation of the angular power spectrum (or angular correlation function) of a map,
  • convolution of a spherical map with an arbitrary circular window,
  • tessellation of the sphere and pixel processing supported down to a pixel size of 0.4 milliarcseconds (equivalent to 3.5 1018 pixels on the sphere),
  • median filtering of a map,
  • search of local extrema in a map,
  • query of pixels located in user defined disks, triangles, polygons, ...
  • processing of binary masks to identify 'holes' in order to fill them, or to apodize masks,
  • visualization of HEALPix sky maps either on the whole sky (using Mollweide or orthographic projections) or on a patch (gnomic or cartesian projections),
  • output in Google Map/Google Sky and DomeMaster format.

The most expensive operations, such a Spherical Harmonics Transform have been carefully optimised and benefit from a shared memory parallelisation based on OpenMP.

Contents of the software package

The software is available in C, C++, Fortran90, IDL/GDL, Java and python. The following modules are provided in each of these languages:

  • a library of tools (subroutines, functions, procedures, modules, classes, ...depending on languages) covering most of the functionnalities described above, as well as supporting ancillary tools (eg, parameter file parsing),
  • a set of stand-alone facilities based on the library above and each implementing one of HEALPix major features (map generation or analysis, filtering, resolution udgrade or downgrade, visualization). These applications are generally run via an interactive dialog or an ASCII parameter file. Their source code can be used as a starting point for user specific developments,
  • an extensive PDF and/or HTML documentation describing in details the API, inner working and limitations of each tool and application.

Finally, some tools (interactive script and Makefile) are provided to manage and facilitate the compilation and installation of one or several of the libraries and facilities, for most combinations of hardwares, operating systems, compilers, ...

Third Party Developements

One can distinguish two kinds of third party developements (defined as not (yet) being part of the official HEALPix package described above):

  • new functionalities, for instance many tools based on Minkowski functionals, wavelets (iSAP, MRS, S2LET, SphereLab), or structure identification (DisPerSE) developed by various research teams can be applied to data stored in HEALPix format,
  • translations, re-implementations or wrapping of (some of) existing functionalities, for instance in Matlab/Octave (Mealpix) and Yorick (YHeal) are available. (See (almost) exhaustive list.)

Context in which the software is used

Software used for the analysis of Planck satellite data.
Data format supported by Aladin visualisation software to represent diffuse astronomical data on the sky.

Publications related to the software

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 17/05/13
  • Minor correction: 17/07/13

LSMM : Majorize-Minimize LineSearch for logarithmic barrier function optimization

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 1.0 - mars 2013
  • License(s): CeCILL-B
  • Status: stable release
  • Support: maintained, no ongoing development
  • Designer(s): Emilie Chouzenoux (LIGM), SaĂŻd Moussaoui (IRCCyN)
  • Contact designer(s): emilie.chouzenoux @ univ-mlv.fr
  • Laboratory, service:

 

General software features

This toolbox allows to determine a suitable stepsize in iterative descent algorithms applied to the minimization of a criterion containing a logarithmic barrier function associated to linear constraints. A Majorization-Minimization (MM) scheme is adopted. It is based on the derivation of a log-quadratic majorant function well suited to approximate the criterion containing barrier terms. The convergence of classical descent algorithms when this linesearch strategy is employed is ensured.

A demo file illustrates the efficiency of the MM linesearch on the Newton minimization of the barrier criterion associated to a random quadratic programming (QP) test problem.

Context in which the software is used

Linearly constrained optimization.

Publications related to the software
  • E. Chouzenoux, S. Moussaoui and J. Idier. "Majorize-Minimize Linesearch for Inversion Methods Involving Barrier Function Optimization." Inverse Problems, Vol. 28, No. 6, 2012.

  • E. Chouzenoux, S. Moussaoui and J. Idier. "Efficiency of Line Search Strategies in Interior Point Methods for Linearly Constrained Optimization." In Proceedings of the IEEE Workshop on Statistical Signal Processing (SSP 2011), pages 101-104, Nice, France, 28-30 juin 2011.

  • E. Chouzenoux, S. Moussaoui and J. Idier. "A Majorize-Minimize Line Search Algorithm for Barrier Function Optimization." In Proceedings of the 17th European Signal Processing Conference (EUSIPCO 2009), pages 1379-1383, Glasgow, UK, 24-28 aoĂ»t 2009. EURASIP Press.

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 06/05/13
  • Minor correction: 06/05/13

RestoVMFB_Lab : Matlab toolbox for image restauration with the Variable Metric Forward-Backward algorithm

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 1.0 - avril 2013
  • License(s): CeCILL-B
  • Status: stable release
  • Support: maintained, no ongoing development
  • Designer(s): Audrey Repetti (LIGM), Emilie Chouzenoux (LIGM)
  • Contact designer(s): audrey.repetti @ univ-mlv.fr
  • Laboratory, service:

 

General software features

This Matlab toolbox allows to restore an image degraded by a linear operator and Gaussian Dependant noise with variance depending linearly on the image. The considered criterion is composed with the neg-log-likelihood of the noise distribution as data fidelity term, the indicator function allowing to constraint the dynamic range and the isotropic total variation favorizing piecewise constant images.

The restoration process uses the Majorize-Minimize Variable Metric Forward-Backward Algorithm.

Context in which the software is used

Image restauration

Publications related to the software

E. Chouzenoux, J.-C. Pesquet and A. Repetti. "Variable Metric Forward-Backward Algorithm for Minimizing the Sum of a Differentiable Function and a Convex Function" Submitted, 2013. Available online at http://www.optimization-online.org/DB_FILE/2013/01...

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 05/06/12
  • Minor correction: 07/06/12

DOLMEN : Numerical 3D software for Eddy Current Non Destructive Testing

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Status: internal use
  • Support: maintained, ongoing development
  • Designer(s): Yahya Choua, Guillaume Krebs, Yann Le Bihan, Alexandro Ospina, Laurent SantandrĂ©a, Houda Zaidi
  • Contact designer(s): yann.le-bihan[at]lgep.supelec.fr
  • Laboratory, service:

 

General software features

DOLMEN is a numerical software dedicated to Eddy Current Non Destructive Testing (EC-NDT). The quasi-stationary Maxwell equations are solved using the Finite Element Method in 3D. The dual electric and magnetic formulations with electric and magnetic combined potentials are used in harmonic regime. First order edge and nodal Whitney tetrahedral elements are used. The gauging conditions are avoided using an iterative solver to ensure the uniqueness of the solution.

Specific developments concerning EC-NDT have been made:

  • Taking into account the probe movement.
  • Automatic mesh adaptation based on a local error estimator using the complementarity between the two formulations.
  • Numerical methods dedicated to the thin geometric structures (flaws, thin lift-off , thin coil, deposit, coating, ...).
  • Transmitter/Receiver with common or separated functions.

This code is based on an object oriented approach using the C++ language. Its software architecture is based on the Freefem++ kernel. It is droved by a Python script and it uses Netgen as Mesh generator. Distributed computing can be used to manage probe displacement.

Context in which the software is used

This software is used in research academic NDT frameworks (European research project VERDICT 2003-2006, Competitiveness cluster SYSTEM@TIC PARIS-REGION, french framework SIMCO-IMPACT, collaborative works with Dassault, CEA-LIST, LSS, Univ. Budapest, ...).

Publications related to the software

A contribution to connect non-conform meshes with overlapping finite elements, H. Zaidi, L. Santandréa, G. Krebs, Y. Le Bihan, "IGTE", Graz, AT, 19 September 2010, pp. 1-6, Proceedings of IGTE.

Electromagnetic Field Computation in Magnetic and Conductive Thin sheets, A. Ospina Vargas, L. Santandréa, Y. Le Bihan, C. Marchand, Sensor Letters", Vol. 7, Issue: 3, June 2009, pp. 480-485.

Adaptive Mesh Refinement and Probe Signal Calculation in Eddy Current NDT by Complementary Formulations, M. Bensetti, Y. Choua, L. Santandréa, Y. Le Bihan, C. Marchand, IEEE Transaction on magnetics, juin 2008, volume 44, issue 6, pp. 1646-1649.

Crack modelling in ECT with combined potential formulations, Y. Choua, L. Santandréa, Y. Le-Bihan, C. Marchand, IEEE Transactions on magnetics, April 2007, Volume 43, Issue 4, pp. 1789-1792.

Using Mortar Element Method for Eddy Current Testing Finite Element Computations, L. Santandrea, Y. Choua, Y. Le Bihan, C. Marchand, COMPUMAG, Aachen (juin 2007).

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 20/01/12
  • Minor correction: 20/01/12

QTLMap : detection of QTL from experimental designs in outbred population

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 0.8.3 - 14 october 2010
  • License(s): CeCILL
  • Status: beta release
  • Support: maintained, ongoing development
  • Designer(s): Pascale Le Roy, Jean-Michel Elsen, Helene Gilbert, Carole Moreno, Andres Legarra, Olivier Filangi
  • Contact designer(s): olivier.filangi@rennes.inra.fr
  • Laboratory, service:

 

General software features

Description

QTLMap is a software dedicated to the detection of QTL from experimental designs in outbred population. QTLMap software is developed by the Animal Genetics Division at INRA (French National Institute for Agronomical Research). The statistical techniques used are linkage analysis (LA) and linkage disequilibrium linkage analysis (LDLA) using interval mapping. Different versions of the LA are proposed from a quasi Maximum Likelihood approach to a fully linear (regression) model. The LDLA is a regression approach (Legarra and Fernando, 2009). The population may be sets of half-sib families or mixture of full- and half- sib families. The computations of Phase and Transmission probabilities are optimized to be rapid and as exact as possible. QTLMap is able to deal with large numbers of markers (SNP) and traits (eQTL).

Functionnalities

  • QTL detection in half-sib families or mixture of full- and half-sib families
  • One or several linked QTL segregating in the population
  • Single trait or multiple trait
  • Nuisance parameters (e.g. sex, batch, weight...) and their interactions with QTL can be included in the analysis
  • Gaussian, discrete or survival (Cox model) data
  • Familial heterogeneity of variances (heteroscedasticity)
  • Can handle eQTL analyses
  • Computation of transmission and phase probabilities adapted to high throughput genotyping (SNP)
  • Empirical thresholds are estimated using simulations under the null hypothesis or permutations of trait values
  • Computation of power and accuracy of your design or any simulated design
Context in which the software is used

QTLMap source code is available under the CeCILL version 2.0 license, a GPL like license.

Utilisateurs

This software is used by genetic researchers to detect a region of the genome that controls an agronomic trait

Cluster Infrastructures

Software dependencies

Installation

  • Suite gcc (>=4.4)
  • CMake 2.6.4

Support

Users mailing list : inscription

Publications related to the software

Legarra A, Fernando RL, 2009. Linear models for joint association and linkage QTL mapping. Genet Sel Evol., 41:43.

Elsen JM, Filangi O, Gilbert H, Le Roy P, Moreno C, 2009. A fast algorithm for estimating transmission probabilities in QTL detection designs with dense maps. Genet Sel Evol., 41:50.

Gilbert H., Le Roy P., Moreno C., Robelin D., Elsen J. M., 2008. QTLMAP, a software for QTL detection in outbred population. Annals of Human Genetics, 72(5): 694.

Gilbert H, Le Roy P., 2007. Methods for the detection of multiple linked QTL applied to a mixture of full and half sib families. Genet Sel Evol., 39(2):139-58.

Moreno C.R., Elsen J.M., Le Roy P., Ducrocq V., 2005. Interval mapping methods for detecting QTL affecting survival and time–to–event phenotypes. Genet. Res. Camb., 85 : 139-149.

Goffinet B, Le Roy P, Boichard D, Elsen JM, Mangin B, 1999. Alternative models for QTL detection in livestock. III. Heteroskedastic model and models corresponding to several distributions of the QTL effect.. Genet. Sel. Evol., 31, 341-350.

Mangin B, Goffinet B, Le Roy P, Boichard D, Elsen JM, 1999. Alternative models for QTL detection in livestock. II. Likelihood approximations and sire marker genotype estimations. Genet. Sel. Evol., 31, 225-237.

Elsen JM, Mangin B, Goffinet B, Boichard D, Le Roy P, 1999. Alternative models for QTL detection in livestock. I. General introduction. Genet. Sel. Evol., 31, 213-224

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 14/12/11
  • Minor correction: 07/09/13

pyFAI : azimuthal integration for 2D detectors

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: 0.9.0 - July 30; 2013
  • License(s): GPL
  • Status: stable release
  • Support: maintained, ongoing development
  • Designer(s): JĂ©rĂ´me Kieffer (Python code), Dimitris Karkoulis (OpenMP & OpenCL), Peter Bösecke (Geometry), V. Armando SolĂ© (Image processing), Manuel Sánchez del RĂ­o (Original idea), Jonathan P. Wright (Ideas), FrĂ©dĂ©ric Emmanuel Picca (Documentation and ideas)
  • Contact designer(s): Jerome.Kieffer@esrf.fr
  • Laboratory, service:

 

General software features

PyFAI is a Python library for azimuthal integration; it allows the conversion of diffraction images taken with 2D detectors like CCD cameras into X-Ray powder patterns that can be used by other software like Rietveld refinement tools (i.e. FullProf), phase analysis or texture analysis.

As PyFAI is a library, its main goal is to be integrated in other tools like PyMca or EDNA. To perform online data analysis, the precise description of the experimental setup has to be known. This is the reason why PyFAI includes geometry optimization code working on "powder rings" of reference samples. Alternatively, PyFAI can also import geometries fitted with other tools like Fit2D.

PyFAI has been designed to work with any kind of detector with any geometry (transmission, reflection, off-axis, ...). It uses the Python library Fabio to read most images taken by diffractometer (Fabio officially supports 12 manufacturers and 20 different image formats).

Context in which the software is used

2D detectors (CCD, CMOS or pixel detectors, ...) have progressively replaced punctual detectors over the 15 last years in the world of diffraction (single crystal, powder diffraction WAXS or small angle scattering SAXS). Those detectors, with wide sensitive area, have spatial resolution of dozens of microns and provide millions of pixels. PyFAI can be used on SAXS and WAXS data to reduce them into 1D (azimuthal integration) or 2D (transformation known as caking).

In order to transform detector images into data to be used by scientists it is necessary to:

  • subtract dark current (correction for the read-out noise)
  • divide by flat-field (correction for the relative sensitivity of pixels or scintillator inhomogeneities)
  • correct for the pixel position (defects of the optical fiber taper)
  • mask out dead pixels
  • convert pixel position from Cartesian space (x,y) to Polar space (2theta, chi)

PyFAI is able to compute all those corrections. Special care has been taken to conserve intensity and surface density by pixel splitting during the re-binning process (which is close to a histogram, but with pixel splitting). The algorithm used is implemented in numpy to provide a bullet-proof version, but faster and more precise version have been implemented in Cython and in OpenCL to achieve best performances with modern graphic cards.

An additional piece of software allows a fast and reliable calibration of the geometry of the experimental setup; allowing online analysis of the data.

Publications related to the software
Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 25/11/11
  • Minor correction: 23/11/12

ROTORINSA : prediction of the dynamic behavior of rotors in bending

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • Web site
  • System:
  • Current version: Version 4.0.4 - March 2011
  • License(s): Proprietary licence -

    A free version may be loaded : http://rotorinsa.insa-lyon.fr/modules/formulaire/index.php?id=2&rub=05

  • Status: stable release
  • Support: maintained, ongoing development
  • Designer(s): Guy FERRARIS, Michel LALANNE, Marie Ange ANDRIANOELY
  • Contact designer(s): rotorinsa@insa-lyon.fr
  • Laboratory, service:

 

General software features

This finite element software is devoted to the prediction of the steady state behavior of monorotors in bending.
Modeling
Node: 4 degrees of freedom.
Shaft: two-node beam element, classical stiffness and mass matrices, axial forces, shear, rotatory inertia and gyroscopic effect are taken into account.
Disk: one-node disk element, rigid and defined by mass and gyroscopic matrices.
Bearings: stiffness and damping matrices which can be non-symmetric and can vary as a function of the speed of rotation; active magnetic bearings.
Specific elements: modeling of particular effects such as couplings, magnetic attraction, stator …

ROTORINSA predicts:
In Statics:
- The deflection of the shaft subjected to gravity and/or forces which can be concentrated.

In Dynamics:
- Natural frequencies and modes in rotation, Campbell diagram, instabilities and damping factors.
- Mass unbalance response, asynchronous force response, response to a harmonic force fixed in space.
- Maximum stresses in the shafts, loads on bearings.
- Elementary energies.

Context in which the software is used

ROTORINSA is used for rotating machinery design and modification of the architecture of existing machines.
ROTORINSA is implemented on more than 20 industrial sites. It has been and it is still used for training at INSA-Lyon in France and in foreign countries.

The expertise of the laboratory has been greatly gained from contracts with companies and state organizations over a period of nearly 30 years.

Publications related to the software

The software is based on the theory presented in:
1. Rotordynamics Prediction in Engineering by Michel Lalanne and Guy Ferraris. J. Wiley, 254 p, 2nd edition 1998.
ISBN 0 471 97288 6
2. Dynamique des rotors en flexion. Guy Ferraris, Michel Lalanne. Techniques de l’ingénieur Traité
GĂ©nie MĂ©canique, B5 110, 1996.

ROTORINSA User manual
Marie Ange ANDRIANOELY - Guy FERRARIS - Michel LALANNE - Alain BERLIOZ - Alain THIVILLIER
Version 4.0.4 2011

ROTORINSA Qualification manual
Guy FERRARIS - Marie Ange ANDRIANOELY - Michel LALANNE - Alain BERLIOZ - Alain THIVILLIER
Version 4.0.4 2011

Higher Edu - Research dev card
Development from the higher education and research community
  • Creation or important update: 25/11/11
  • Minor correction: 25/11/11

MULTIROTOR : prediction of the dynamic behavior of multirotors

This software was developed (or is under development) within the higher education and research community. Its stability can vary (see fields below) and its working state is not guaranteed.
  • System:
  • Current version: March 2010
  • License(s): Proprietary licence
  • Status: stable release
  • Support: maintained, ongoing development
  • Designer(s): Guy FERRARIS, Michel LALANNE
  • Contact designer(s): rotorinsa@insa-lyon.fr
  • Laboratory, service:

 

General software features

This finite element software is devoted to the prediction of the dynamic behavior of parallel multirotors in bending.
Modeling
Node: 4 degrees of freedom.
Shaft: two-node beam element, classical stiffness and mass matrices, axial forces, shear, rotatory inertia and gyroscopic effect are taken into account.
Disk: one-node disk element, rigid, defined by mass and gyroscopic matrices effects.
Bearings: stiffness and damping matrices which can be non-symmetric and can vary as a function of the speed of rotation.
Specific elements: modeling of particular effects such as couplings, magnetic attraction, stator …

MULTIROTOR predicts:
In Statics:
- The deflection of the shafts subjected to gravity and/or forces which can be concentrated.

In Dynamics:
- Natural frequencies and modes in rotation, Campbell diagram, instabilities and damping factors.
- Mass unbalance response, asynchronous force response, response to a harmonic force fixed in space.
- Maximum stresses in the shafts, loads on bearings.
- Elementary energies, kinetic and strain energies in elements.

Context in which the software is used

MULTIROTOR is used for rotating machinery design, especially for jet engines and for the modification of the architecture of existing machines.
MULTIROTOR is used for training at INSA-Lyon, in France and in foreign countries.

The expertise of the laboratory has been greatly gained from contracts with companies and state organizations over a period of nearly 30 years.

Publications related to the software

The software is based on the theory presented in:
1. Prédiction du comportement dynamique des moteurs d’avion : vitesses critiques, effets de balourd. Patrick Berthier, Guy Ferraris, Michel Lalanne. J. Mec.Th. et Appl, 5. 1986.
2. Prediction of the dynamic behavior of non-symmetric coaxial co-or counter rotating rotors .G Ferraris, V.Maisonneuve , M.Lalanne. J of Sound and Vibration 1996 195(4), 649-666.
3. Rotordynamics Prediction in Engineering by Michel Lalanne and Guy Ferraris. J. Wiley, 254 p, 2nd edition 1998. ISBN 0 471 97288 6
4. Dynamique des rotors en flexion. Guy Ferraris, Michel Lalanne. Techniques de l’ingénieur Traité Génie Mécanique, B5 110, 1996.

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