0000000000138615
AUTHOR
Jean François Fontaine
Experimental and numerical modelling of the effects of process parameters in the Aquadraw deep Drawing
International audience
Specification analysis and 3D inspection without contact
International audience
Digital Correlation Method Based on Microgeometrical Texture Patterns for Strain Fields Measurements
International audience; Digital correlation method is widely used in experimental mechanics to obtain the deformation field. Currently this method is applied with digital images of the initial and deformed surface sprayed with black or white painting. Speckle patterns are then captured and the correlation can be made with high 0.01 pixel accuracy in 2D-cases. In three-dimensions, the stereo-correlation can be used with a lower accuracy. The work presented in this paper, is a first approach based on the use of a 3D laser scanner in the objective of three-dimensional strain field measurement. The digital speckle patterns are not given by gray level but from the micro-geometrical surface textu…
Digital Correlation Method Based on Microgeometrical Texture Patterns for Displacement Field Measurements
International audience
Influence of the Microgeometry on the Cylindrical Fit Characteristics
International audience
3D surfaces automated acquisition using non contact sensor with repect of metrological conditions
International audience
3D Full Field Measurement Based on Micro-geometrical Texture Patterns
International audience; The work presented is based on the laser scanning device that is now currently used in the reverse engineering or tri-dimensionnal inspection domains. The interest of this technique is to measure directly the point clouds in 3D coordinates. That permits to reduce the approximations due to the different correlations made in grey level images stereo-correlation. The sensor is mounted on a CMM that moves it and gives it a good orientation in the measurement space.The pattern is determined by the natural or artificially created micro-geometry (roughness) of the surface product. A depth image is obtained after filtering of the shape of the object. This filtering can be ca…
Planification de la trajectoire automatique pour la mesure d'objet 3D sans contact
International audience
Parameters Analysis Influencing 3D Measurement without Contact by Laser Scanner to Make a Compensation Model
International audience; The 3D measurement is more and more important in industrial applications. There are different applications like 3D inspection or reverse engineering. In the both cases, the classical techniques by contact present the advantage of a good accuracy but the costs are expensive because of the slow progress of the measurement. In an other hand, the without contact technologies have a high cadency of points measurement but with a lower accuracy. We present in this study a methodology to estimate the measurement uncertainties and to correct the systematic error. The global error can be separated in random error (in the order of 25 m for the considered laser scanner) and in …
Digital Correlation Method Based on Micro-geometrical Texture Pattern for Strain Field Measurement
International audience; Image correlation methods are widely used in experimental mechanics to obtain displacement field measurements. Currently, these methods are applied using digital images of the initial and deformed surfaces sprayed with black or white paint. Speckle patterns are then captured and the correlation is performed with a high degree of accuracy to an order of 0.01 pixels. In 3D, however, stereo-correlation leads to a lower degree of accuracy. Correlation techniques are based on the search for a sub-image (or pattern) displacement field. The work presented in this paper introduces a new correlation-based approach for 3D displacement field measurement that uses an additional …
I.D.A New Model for the Design of Tight Interference Fit Taking Into Account the Surface Texture M.M.E'2000
International audience; The tight interference fit is very largely applied in industry, but, in all proposed models of calculation, one supposes that the contact interfaces are always perfect which leads us to establish some limits which are not only contrary to the grip principle but also greatly increase production costs. This paper presents a new model that takes into account the macro and micro-geometrical defects for calculating the contact pressure. We show that it is possible to reduce the cost and assure the fit resistance. The form defect can be integrated in FEM codes and the surface texture can be represented by a loss of interference due to the plastic strains of the asperities.…
Modelling of a Circular Shrinkage Fit in Taking into account of the Form Defect
International audience
Une approche maîtrisée de la mesure 3D sans contact des pièces mécaniques par scanning laser, a Controlled Approach of the 3D Inspection of Mechanical Parts with Laser Scanner
International audience
Utilisation des bras de mesure polyarticulés portables
International audience; Les bras de mesure polyarticulés portables (articulated arm coordiante measuring machine : AACMM) sont des machines à mesurer tridimensionnelles portables comportant 6 ou 7 axes de rotation. Ils peuvent être utilisés actuellement avec un système de palpage à contact (statique ou dynamique) ou un scanner à nappe laser. Ils sont conçus principalement pour faire de la mesure sur site et dans différents environnements. Leurs flexibilité, facilité d’utilisation et coût moins élevé que le coût des machines à mesurer tridimensionnelles classiques, font partie des éléments phares permettant à ces dispositifs d'intégrer complétement les projets de l’usine du futur. Toutefois,…