Abstract: The invention relates to a method for processing images obtained by a diffraction detector, of a crystalline or polycrystalline material, in which a first image of the material is acquired in a state of reference as well as a second image of the material in a deformed state. The invention is characterised in that, in a calculator, during a first step (E6, E12), a current elastic deformation gradient tensor Fe is given a value determined by calculation, during a second step (E7), the current displacement field induced by the tensor Fe is calculated, during a third step (E8), third digital values of a deformed image {hacek over (g)}(x)=g(x+u(x)) corrected by the current displacement field are calculated, and during an iterative algorithm, iterations of the second and third steps (E12, E7, E8) are carried out on modified values of the tensor r Fe until a convergence criterion is met in relation to the correction to the current value of Fe.

Abstract: A computer-implemented method for identifying mechanical parameters of an object subjected to mechanical stress is provided. The method comprises a step of acquiring, by an imaging means, images of the object taken before and during the application of the mechanical stress, three steps of calculating the effects due to the stress carried out either on the basis of the modeling of the recorded images or on the basis of a theoretical mechanical modeling of the stress, a step of defining a functional equal to the difference between the two models and a last step of minimizing said functional so that the experimental model is as close as possible to the theoretical mechanical model. Additional measurements make it possible to refine the method.

Abstract: A method of characterizing a part including obtaining an X-ray tomography image of the part and then a step of correlating the image with a reference wherein the correlation step includes searching among a predefined set of X-ray tomography image transformations for a transformation that minimizes the difference between the image and the reference in order to characterize the inside of the part.

Abstract: A computer-implemented method for identifying mechanical parameters of an object subjected to mechanical stress is provided. The method comprises a step of acquiring, by an imaging means, images of the object taken before and during the application of the mechanical stress, three steps of calculating the effects due to the stress carried out either on the basis of the modeling of the recorded images or on the basis of a theoretical mechanical modeling of the stress, a step of defining a functional equal to the difference between the two models and a last step of minimizing said functional so that the experimental model is as close as possible to the theoretical mechanical model. Additional measurements make it possible to refine the method.

Abstract: The invention relates to a method for processing images obtained by a diffraction detector, of a crystalline or polycrystalline material, in which a first image of the material is acquired in a state of reference as well as a second image of the material in a deformed state. The invention is characterised in that, in a calculator, during a first step (E6, E12), a current elastic deformation gradient tensor Fe is given a value determined by calculation, during a second step (E7), the current displacement field induced by the tensor Fe is calculated, during a third step (E8), third digital values of a deformed image {hacek over (g)}(x)=g(x+u(x)) corrected by the current displacement field are calculated, and during an iterative algorithm, iterations of the second and third steps (E12, E7, E8) are carried out on modified values of the tensor r Fe until a convergence criterion is met in relation to the correction to the current value of Fe.

Abstract: A tomography scanner includes at least one first emission source (GX1), one first matrix detector (D1), and a computer (C) arranged to produce an initial tomography of an object (E) based on radiographs arising from the first matrix detector, taken from various angles. The tomography scanner further includes a second emission source (GX2) and a second matrix detector (D2) arranged so that, when the object is subjected to a loading that is known at a given instant in time, the computer determines the changes in the object subjected to said loading based only on the information from the first radiograph of the object under loading arising from the first matrix detector, from the second radiograph of the object under loading arising from the second matrix detector and the initial tomograph, the first radiograph and the second radiograph being taken simultaneously at the same given instant in time.

Abstract: A method allowing the cracking of a material to be controlled, and a device for the implementation of the method are disclosed. A target cracking path is defined in a given volume of material. Mechanical loads are applied to the material in order to control the propagation of a crack in the volume so that the crack propagates along the target path. In order to prevent an unstable propagation of the crack, a stabilization load especially designed for stabilizing the propagation of the crack is applied to the volume.

Abstract: A method allowing the cracking of a material to be controlled, and a device for the implementation of the method are disclosed. A target cracking path is defined in a given volume of material. Mechanical loads are applied to the material in order to control the propagation of a crack in the volume so that the crack propagates along the target path. In order to prevent an unstable propagation of the crack, a stabilization load especially designed for stabilizing the propagation of the crack is applied to the volume.

Abstract: A method of characterizing a part including obtaining an X-ray tomography image of the part and then a step of correlating the image with a reference wherein the correlation step includes searching among a predefined set of X-ray tomography image transformations for a transformation that minimizes the difference between the image and the reference in order to characterize the inside of the part.

Abstract: Disclosed is a method for measuring movement and/or deformation of a study part subjected to an external stress, the method implementing a color digital image acquisition device and image correlation unit. The method includes: acquisition (250) of a plurality of color digital images of the surface of the study part by way of the color digital image acquisition device during the application of an external stress on the study part, and processing (260) of the color digital images acquired in the step of acquisition of a plurality of color digital images so as to highlight contrasting details on variable scales.

Abstract: In the field of methods of three-dimensional measurement of an object by stereo-correlation, methods require at least two cameras connected to image processing means. These methods include at least a first step of calibration of the two image planes and a second step of spatial matching between these two image planes. These two steps can be followed by a third step of temporal matching. The method provided requires objects, the surface of which has a parametric representation, i.e. a mathematical representation of the object surface having the form of a decomposition over a scalar function basis. The parametric representation is implemented during the first calibration step and/or during the second and third steps of spatial or temporal matching.

Abstract: Tomographs comprise at least one first emission source, one first matrix detector and calculation means arranged to produce an initial tomograph of an object on the basis of radiographs arising from the first matrix detector taken from various angles. The tomography scanner comprises a second emission source and a second matrix detector arranged so that, when the object is subjected to a stress which is known at a given instant in time, the calculation means determine the changes in the object subjected to stress based only on the information from a first radiograph of the object under stress arising from the first matrix detector, from a second radiograph of the object under stress arising from the second matrix detector and the initial tomograph, the first radiograph and the second radiograph being taken at the same given instant in time.

Abstract: Disclosed is a method for measuring movement and/or deformation of a study part subjected to an external stress, the method implementing a color digital image acquisition device and image correlation unit. The method includes: acquisition (250) of a plurality of color digital images of the surface of the study part by way of the color digital image acquisition device during the application of an external stress on the study part, and processing (260) of the color digital images acquired in the step of acquisition of a plurality of color digital images so as to highlight contrasting details on variable scales.

Abstract: In the field of methods of three-dimensional measurement of an object by stereo-correlation, methods require at least two cameras connected to image processing means. These methods include at least a first step of calibration of the two image planes and a second step of spatial matching between these two image planes. These two steps can be followed by a third step of temporal matching. The method provided requires objects, the surface of which has a parametric representation, i.e. a mathematical representation of the object surface having the form of a decomposition over a scalar function basis. The parametric representation is implemented during the first calibration step and/or during the second and third steps of spatial or temporal matching.