On the use of a penalized least squares method to process kinematic full-field measurements
Article dans une revue avec comité de lecture
This work is aimed at exploring the performances of an alternative procedure to smooth and differentiate full-field displacement measurements. After recalling the strategies currently used by the experimental mechanics community, a short overview of the available smoothing algorithms is drawn up and the requirements that such an algorithm has to fulfil to be applicable to process kinematic measurements are listed. A comparative study of the chosen algorithm is performed including the 2D penalized least squares method and two other commonly implemented strategies. The results obtained by penalized least squares are comparable in terms of quality to those produced by the two other algorithms, while the penalized least squares method appears to be the fastest and the most flexible. Unlike both other considered methods, it is possible with penalized least squares to automatically choose the parameter governing the amount of smoothing to apply. Unfortunately, it appears that this automation is not suitable for the proposed application since it does not lead to optimal strain maps. Finally, it is possible with this technique to perform the derivation to obtain strain maps before smoothing them (while the smoothing is normally applied to displacement maps before the differentiation) which can lead in some cases to a more effective reconstruction of the strain fields.
Cette publication figure dans le(s) laboratoire(s) suivant(s)
Visualiser des documents liés par titre, auteur, créateur et sujet.
Communication avec acteMOULART, Raphaël; ROTINAT, René (2013)This study deals with the characterisation of the mechanical behaviour of an austenitic stainless steel (316L) at the micrometric scale in its elasto-plastic domain. For that, the full-field “grid method”, adapted to this ...
Article dans une revue avec comité de lectureMOULART, Raphaël; ROTINAT, René; PIERRON, Fabrice (Elsevier, 2009)This work deals with the study of the local onset of microplasticity in a steel specimen under tensile test through the use of a full-field strain measurement method at the micrometric scale. The kinematic measurements ...
Communication avec acteROTINAT, René; MOULART, Raphaël; NUNIO, François; VEDRINE, Pierre (ISEM 2015, 2015)This study deals with of the experimental methodology developed in order to identify the elastic properties of superconducting ring-shaped windings. Mechanical tensile tests were conducted on specimens associated to a ...
Communication avec acteMOULART, Raphaël; ROTINAT, René (SEM 2015, 2015)This work proposes an alternative procedure to smooth and differentiate experimental full-field displacement measurements to get strain fields. This one, the penalized least squares method, relies on the balance between ...
Communication avec acteMOULART, Raphaël; ROTINAT, René (2015)Ce travail propose d’étudier une procédure alternative pour lisser puis dériver des mesures de champs de déplacement expérimentaux pour obtenir des champs de déformations. Celle-ci, la méthode des moindres carrés pénalisés, ...