FR3135220A1 - METHOD AND SYSTEM FOR REPAIRING AN OBJECT - Google Patents

Abstract

METHOD AND SYSTEM FOR REPAIR OF AN OBJECT Method (100) for repairing an object presenting at least one surface defect, the method comprising the steps of determining (110) the position of the defect on the object, selection (120 ) of a three-dimensional marker, positioning (125) of the selected marker on the object, determination (147) of a volume to be machined, machining (155) of the object and reloading (165) of the machined volume. Abstract figure: Fig. 1

Description

METHOD AND SYSTEM FOR REPAIRING AN OBJECT FIELD OF INVENTION

The present invention relates to a method for repairing an object having a surface defect. More specifically, the present invention relates to a method for repairing an object based on marking defect areas.

The present invention also relates to a system for repairing an object having a surface defect.

STATE OF THE TECHNIQUE

Some factory parts, such as castings used in the aeronautical, naval or automobile industries, may have surface defects due to their manufacturing or wear. These defects, of a geometric or metallurgical nature, must be corrected in order to restore the desired geometric and metallurgical properties for these parts.

Some methods of repairing such defects are based on manual determination of the position and size of the defects. However, these methods are not satisfactory because they are slow and imprecise.

Other known methods automatically determine the volume of defects, for example by three-dimensional scanning. However, these methods still require precise positioning of the object under the measuring device in order to determine the coordinates of the area of the surface in which the defect is located. These methods therefore also involve a loss of time and precision when repairing defects.

The aim of the invention is to provide a method which allows the repair of surface defects in an automated, precise and/or rapid manner.

SUMMARY

1. détermination de la position du défaut sur l’objet, le dit défaut ayant une surface externe, et des caractéristiques géométriques du défaut, lesdites caractéristiques géométriques comprenant au moins les deux dimensions de la surface externe du défaut et une forme géométrique du défaut ;
2. sélection d’un marqueur tridimensionnel comprenant au moins une base dont les dimensions sont supérieures ou égales à celles de la surface du défaut, ledit marqueur étant choisi dans un ensemble de marqueurs préexistant ;
3. positionnement du marqueur sélectionné sur l’objet de manière à ce que la base du marqueur recouvre au moins la totalité de la surface du défaut, la position, les dimensions, et/ou la forme du marqueur définissant un volume de défaut et une zone de défaut ;
4. détermination d’un volume à usiner selon le volume de défaut défini à l’étape c) ;
5. usinage de l’objet par retrait du volume à usiner déterminé à l’étape d) ; et
6. rechargement du volume usiné à l’étape e) par ajout de matière.

For this purpose, the present invention relates to a method of repairing an object presenting at least one surface defect, the method comprising the following steps:

1. determination of the position of the defect on the object, said defect having an external surface, and geometric characteristics of the defect, said geometric characteristics comprising at least the two dimensions of the external surface of the defect and a geometric shape of the defect;
2. selection of a three-dimensional marker comprising at least one base whose dimensions are greater than or equal to those of the surface of the defect, said marker being chosen from a set of pre-existing markers;
3. positioning of the selected marker on the object so that the base of the marker covers at least the entire surface of the defect, the position, dimensions, and/or shape of the marker defining a defect volume and a zone of default ;
4. determination of a volume to be machined according to the defect volume defined in step c);
5. machining of the object by removing the volume to be machined determined in step d); And
6. reloading of the volume machined in step e) by adding material.

After having identified a defect on the surface of an object, the user selects a three-dimensional (or three-dimensional or 3D) marker from a pre-existing set of markers, i.e. from a library of markers bringing together markers of different dimensions and shapes. . The user therefore has access to a wide variety of dimensions, namely surface dimensions (in the plane of the surface of the object), thickness (or depth, i.e. dimension extending to the normal of the plane of the object). surface of the object) and of different shapes.

The use of a marker allows you to almost arbitrarily position the marked object in the workspace of the repair system. Indeed, the position and geometry of the defect in the system benchmark are deduced directly from the characteristics of the marker. This therefore makes it possible to precisely and automatically define the position of the defect on the surface of the object, avoiding multiple manipulations on the part of the operator, loss of time and precision when placing the object in the workspace.

The dimensions and shape of the marker also make it possible to know the extent of the defect on the surface of the object and also serve as an indicator to generate the tool trajectories precisely during the machining (e) and reloading stages. (f). The use of markers therefore also makes it possible to automate the repair process by facilitating and automatic generation of the trajectory of the machining and reloading means.

In addition, a certain amount of information can be encoded depending on the shape, color and/or size of the marker. For example, the characteristics of the marker make it possible to encode the depth of machining, the shape of the defect, the type of machining, the type of resurfacing, the material to be used for resurfacing, thus making the method even more automated. .

Finally, the use of markers allows the object to be repaired more quickly when it has several defects. In this case, several markers are positioned on the different surface defects for simultaneous repair of said defects. Once the markers are positioned, the geometric characteristics (dimensions, shapes) and the position are directly known for each of the defects.

In addition, the steps for determining the volume of the defect as well as the steps for machining and reloading the defects are fully automated so that several defects can be repaired on the same object without human intervention.

According to one embodiment, the method further comprises a step of determining a surface model of the defect zone.

• détermination, par scan tridimensionnel, d’une surface de la zone de défaut après rechargement du volume usiné ;
• comparaison de ladite surface avec le modèle de surface de la zone de défaut ;
• usinage ou rechargement de la surface de la zone de défaut en fonction du résultat de ladite comparaison.

According to one embodiment, the method further comprises a surface finishing step comprising the following steps:

• determination, by three-dimensional scan, of a surface of the defect zone after reloading the machined volume;
• comparison of said surface with the surface model of the defect zone;
• machining or resurfacing of the surface of the defect zone depending on the result of said comparison.

Implementing a finishing step makes it possible to recover the desired geometric properties.

According to one embodiment, the method further comprises an additional post-treatment step comprising polishing the surface of the defect zone, heat treatment of the defect zone, and/or treatment by mechanical or acoustic waves of the fault area.

The implementation of a post-processing step makes it possible to recover the desired metallurgical properties.

According to one embodiment, the machining is carried out by milling, drilling and/or cutting.

According to one embodiment, the reloading is carried out by additive manufacturing.

According to one embodiment, the determination of the position of the defect on the object and the dimensions of the surface of the defect is carried out by non-contact measurement.

Determining the position of the defect on the object and the dimensions of the defect surface by non-contact measurement makes it possible to avoid damaging or deforming the object during measurement. This also helps avoid contamination of objects requiring minimal surface pollution. Finally, this also allows a faster determination compared to measurements by palpation for example.

According to one embodiment, the contactless measurement is chosen from laser profilometry, laser scanning, three-dimensional scanning, instantaneous three-dimensional imaging, radiography and/or tomography.

The use of a laser scan makes it possible to collect point-by-point positions using two-dimensional scanning.

Using a laser profilometer allows positions to be collected along a laser line, by scanning one dimension along that line, rather than at a point. Thus, a single sensor is sufficient to carry out a three-dimensional measurement.

The use of a three-dimensional scan makes it possible to take an instantaneous measurement (“snapshot” in English) of the entire surface without requiring scanning.

According to one embodiment, the markers are made of a machinable material.

The use of markers made from a machinable material allows the markers to be left in place after the defect depth measurement. In this case, the marker is machined at the same time as the fault area, so as to automate the repair process as much as possible. This minimizes human intervention and therefore increases the speed and precision of the repair.

• un ensemble de marqueurs ; et
• une machine de réparation comprenant ;
  • au moins un moyen d’enlèvement de matière ;
  • au moins un moyen d’ajout de matière ;
  • un moyen de mesure sans contact configuré pour déterminer une position du défaut sur l’objet et des caractéristiques géométriques du défaut, lesdites caractéristiques géométriques comprenant au moins les deux dimensions de la surface du défaut ; et
  • un contrôleur comprenant au moins :
    • un premier processeur configuré pour générer un volume à usiner et/ou un volume à recharger sur base des données fournies par le moyen de mesure sans contact et de la position du défaut fournie par le moyen de mesure sans contact ; et
    • un deuxième processeur configuré pour générer des trajectoires des moyens d’enlèvement et/ou d’ajout de matière sur base du volume généré par le premier processeur.

The present invention also relates to a system for repairing an object presenting at least one surface defect, the system being configured to implement the repair method according to one of the above embodiments and comprising:

• a set of markers; And
• a repair machine comprising;
  • at least one material removal means;
  • at least one means of adding material;
  • non-contact measuring means configured to determine a position of the defect on the object and geometric characteristics of the defect, said geometric characteristics comprising at least the two dimensions of the surface of the defect; And
  • a controller comprising at least:
    • a first processor configured to generate a volume to be machined and/or a volume to be recharged based on the data provided by the contactless measuring means and the position of the defect provided by the contactless measuring means; And
    • a second processor configured to generate trajectories of the material removal and/or addition means based on the volume generated by the first processor.

The repair system makes it possible to know the position of the different means of material removal, material addition and contactless measurement in a single coordinate frame of reference without requiring a change of frame calculation. Thus, by avoiding coordinate conversion and repositioning of the object at each step, it achieves better repair accuracy. This also saves time because no manipulation of the object is required between each step.

The contactless measuring means makes it possible, thanks to the determination of the position and shape of the marker on the object, to almost arbitrarily position the marked object in the working space of the repair system, the position of the fault area in the workspace being determined by the position of the marker.

In one embodiment, the system further comprises a first module for generating a surface model of the object based on the data provided by the contactless measuring means.

In one embodiment, the system further comprises a second module for determining the position and dimensions of the positioned marker.

In one embodiment, the at least one means of adding material is a device allowing reloading by additive manufacturing among material projection, laser deposition or electric arc deposition.

In one embodiment, the contactless measuring means is chosen from laser profilometry, three-dimensional scanning, instantaneous three-dimensional imaging, radiography and/or tomography.

DEFINITIONS

In the present invention, the terms below are defined as follows:

“ Base of the marker ” concerns the surface of the marker intended to be brought into contact with the object and/or surface defect.

“ On the surface ” or “ surface ” describes the positioning of defects at a shallow depth in the volume of the object. By shallow depth, we mean a depth less than 10% of the dimension of the object comprising the defect.

“ Marker ” concerns a three-dimensional element of previously known size and shape allowing, once placed on the object, to define (or mark) a defect zone.

“ Reloading ” concerns an addition of material in order to fill a deficit volume.

“ External surface of the defect ” concerns the surface of the defect defined by projection of the three-dimensional shape of the defect onto the surface of the object.

“ Machining ” concerns the removal of material from an object.

DETAILED DESCRIPTION

For this purpose, the present invention relates to a method 100 for repairing an object 305 having at least one surface defect 303. The steps of the method 100 are schematically represented in the .

1. détermination de la position du défaut 303 sur l’objet 305, le dit défaut 303 ayant une surface externe, et des caractéristiques géométriques du défaut 303, lesdites caractéristiques géométriques comprenant au moins les deux dimensions de la surface externe du défaut 303 et une forme géométrique du défaut 303 ;
2. sélection d’un marqueur tridimensionnel comprenant au moins une base dont les dimensions sont supérieures ou égales à celles de la surface du défaut 303, ledit marqueur 200 étant choisi dans un ensemble de marqueurs préexistant ;
3. positionnement du marqueur 200 sélectionné sur l’objet 305 de manière à ce que la base du marqueur 200 recouvre au moins la totalité de la surface du défaut 303, la position et les dimensions du marqueur 200 définissant un volume de défaut et une zone de défaut;
4. détermination d’un volume à usiner 307 selon le volume de défaut défini à l’étape c) ;
5. usinage de l’objet 305 par retrait du volume à usiner 307 déterminé à l’étape d) ; et
6. rechargement du volume usiné à l’étape e) par ajout de matière.

Said method comprises the following steps:

1. determination of the position of the defect 303 on the object 305, said defect 303 having an external surface, and geometric characteristics of the defect 303, said geometric characteristics comprising at least the two dimensions of the external surface of the defect 303 and a geometric shape defect 303;
2. selection of a three-dimensional marker comprising at least one base whose dimensions are greater than or equal to those of the surface of the defect 303, said marker 200 being chosen from a set of pre-existing markers;
3. positioning of the selected marker 200 on the object 305 so that the base of the marker 200 covers at least the entire surface of the defect 303, the position and dimensions of the marker 200 defining a defect volume and a defect zone ;
4. determination of a volume to be machined 307 according to the defect volume defined in step c);
5. machining of the object 305 by removing the volume to be machined 307 determined in step d); And
6. reloading of the volume machined in step e) by adding material.

Object 305 can be any type of object. Preferably, object 305 is a foundry part used in industry, for example, the aeronautical, naval or automobile industry. For example, item 305 is a metal alloy casting.

Object 305 is characterized by a surface defining its volume in three dimensions. This surface is called the surface of the object.

On the surface or near the surface of the object to be repaired is a defect 303 or a plurality of defects 303.

Each defect 303 can be associated with a local orthogonal three-dimensional axial system. In this local system, two of the axes are defined substantially in the average plane of the surface of the object where the defect 303 is located. The third axis is therefore substantially perpendicular (normal) to the surface of the object where the defect is located. default 303.

Each defect 303 has its own geometric characteristics. These geometric characteristics include the geometric shape of the defect 303 as well as its dimensions along each of the axes of the associated local system. The dimensions along the first two axes of the local system make it possible to define the external surface of defect 303 and are hereinafter called surface dimensions. Indeed, the external surface of the defect 303 is defined as the projection of the three-dimensional shape of the defect 303 on the plane formed by these first two axes. The third axis allows you to define the depth of defect 303.

The defects 303 repairable by the repair method of the present invention are surface defects 303 (or surface defects). The notion of surface defect 303 is defined as a function of the dimension of the object 305 along the third axis of the local system, that is to say perpendicular to the surface of the object. Thus, a surface defect 303 is a defect extending to a depth less than 10% of the dimension of the object 305 along this third axis. Typically, a surface defect 303 is located at a depth of between 0 and 10 centimeters, preferably between 0.1 millimeter and 3 centimeters.

Defect 303 to be repaired may be a geometric defect (crack, hole, etc.) or a metallurgical defect (well, blowhole, etc.). For example, defect 303 is a manufacturing defect or a defect due to wear of object 305.

The first step 110 of the method is the determination of the position of the defect 303 on the object 305. This first step 110 can be carried out manually by an operator by determining the coordinates of the defect(s) 303 on the object 305. Alternatively, this first step 110 can be carried out by automatic detection of defects, for example by a Non-Destructive Testing (NDT) method. The NDT method can be radiography or tomography. This alternative embodiment is preferably carried out when the object 305 is positioned at the location of the repair, for example, in a working space of a repair machine (a repair system comprising a repair machine of the invention is described below).

The second step 120 is the selection of a marker 200 from a pre-existing set of markers (also called physical marker library). An example set of markers is shown in . In one embodiment, each of the markers 200 of the set of markers has at least one characteristic (dimension, shape, color, etc.) which is recorded in a database (also called digital library of markers). For example, the database includes the digital three-dimensional representation file of each of the markers 200 (CAD file or “computer aided design” - CAD - in English).

A marker, also called a beacon, template or indicator, is an element making it possible to identify (or mark) a defect 303 on the surface of the object 305. Thus, each defect 303 to be repaired is marked (or spotted) by a marker.

The marker 200 is a three-dimensional (3D) element having at least one base, as shown in Fig. . This base is configured to be in contact with the surface of the object 305. Optionally, this base can comprise an adhesive surface, such as a coating comprising an adhesive glue or a “modeling clay” type material, capable of being fix on the object 305. The dimensions and shapes of the marker 200 have few constraints. For example, the size of the 200 marker can vary from a few millimeters to a few centimeters. The shape of marker 200 can be arbitrary (“free form” in English) or correspond to a simple geometric shape (sphere, cube, etc.). In another example, marker 200 may be a combination of simple geometric shapes.

Advantageously, the marker 200 makes it possible to encode a certain amount of information used during the repair of the defect 303. This information can be encoded as functions of the height, color and/or geometric shape of the marker. For example, the size of marker 200 is representative of the depth of defect 303 for which it is selected. In another example, the geometric shape of the marker 200 is representative of the geometric shape of the defect 303. In yet another example, the color of the marker 200 is representative of the type of machining to be carried out during the repair. In the embodiment in which the marker 200 is a combination of simple geometric shapes, each of the geometric shapes can be representative of different machining information.

It is advantageous for the markers 200 of the set of markers to have varied characteristics (size, shape and/or color) in order to be able to represent a large quantity of defects 303 having different characteristics on the surface of a large quantity of objects 305 having different characteristics. In addition, these sizes, shapes and colors of markers 200 must be sufficiently unique (characteristics) not to be present elsewhere in the measurement area of the object 305.

The 200 marker is selected based on at least two criteria: the dimensions of its base must be greater than or equal to those of the external surface of the defect and its dimensions (shape and/or height) must be representative of the volume of the defect. Advantageously, this makes it possible to generate machining and reloading tool paths as close as possible to reality. For example, the dimensions of the base of marker 200 are equal to the external surface of the defect and the height of marker 200 is equal to the depth of the defect. The marker 200 can then be selected so that its shape and/or color characteristics represent other information related to the defect and/or the repair to be carried out. Indeed, as described above, this information can be encoded in the shape, height and/or color of the marker.

This second step 120 can be carried out manually by an operator by determining the dimensions of the defect 303 and/or the nature of the material constituting the object 305 at the location of the defect 303. Alternatively, this second step 120 can be carried out by automatic determination dimensions of the defect 303, for example by a CND method. This alternative embodiment is preferably carried out when the object 305 is positioned at the location of the repair, for example, in the working space of the repair machine.

The third step 125 is the positioning of the marker 200 selected on the object 305 so that the base of the marker 200 covers at least the entire surface of the defect 303 for which it was selected as shown in Figure 1. . This third step 125 can be carried out manually by an operator or automatically, for example using a robotic arm included in the repair system. The automatic embodiment is preferably carried out when the object 305 is positioned at the location of the repair, for example, in the working space of the repair machine.

According to one embodiment, the marker 200 is fixed to the surface of the object 305. The fixing of the marker 200 is preferably a reversible fixing. For example, the fixation can be adhesive. Fixing can be done by applying an adhesive glue between the object 305 and the marker 200 or directly using the adhesive surface of the marker 200 if necessary.

The object 305 can then be scanned 130 in order to determine the position on the object 305 of the at least one defect 303 to be repaired as well as its geometric characteristics. An embodiment of the scan of the object 305 is shown in the .

According to one embodiment, the determination of the position of the defect 303 on the object 305 and the dimensions of the surface of the defect 303 is carried out by non-contact measurement. In a specific configuration of this embodiment, the contactless measurement is chosen from laser profilometry, laser scanning, three-dimensional scanning, instantaneous three-dimensional imaging, radiography and/or tomography.

The determination of the position of the defect 303 on the object 305 can be done by recognition 140 of the marker 200. Indeed, during the recognition step 140, the contactless measurement can make it possible to record data linked to the position of the marker 200. This data is then analyzed by a controller to determine the position of the marker 200 in the common reference coordinate system of the repair machine.

During the recognition step 140, the contactless measurement can also determine, on the basis of the characteristics of the marker, the geometric characteristics of the defect 303 on which the marker 200 is positioned. Indeed, the marker 200 having been selected to represent the dimensions of the defect 303, determining the dimensions and/or shape of the marker 200 makes it possible to determine the dimensions of the defect 303. The data measured during the non-contact measurement are analyzed by the controller in order to determine, in particular, the two dimensions of the defect 303. the external surface of the defect 303 as well as the depth of the defect 303.

This determination of position, dimensions, and/or shape of the marker 200 by the controller can be done using, for example, a point-set registration algorithm. point-cloud registration” or “scan matching” in English) such as ICP (“Iterative Closest Point” in English). This determination makes it possible to associate the marker 200 belonging to the physical marker library with an entry in the database (digital marker library).

The dimensions or shape of the marker 200 define a defect volume for the marked defect 303.

The position of the marker 200 and the two dimensions of the external surface of the defect 303 define a defect zone for each defect 303 marked. The defect zone is characterized by a surface approximately centered on the defect 303 and whose dimensions are slightly greater (from a few millimeters to a few centimeters) than those of the external surface of the defect 303.

In addition, contactless measurement can make it possible to determine the shape and/or color of the marker 200 in order to access the information which can be encoded in the marker, for example via the digital marker library. Advantageously, the recovery of information encoded in the marker 200 makes it possible to deduce the volume of the defect, a means of machining and/or material removal to be used in order to repair the object 305 optimally.

The fourth step is the determination 147 of a volume to be machined 307 as a function of the defect volume determined in the recognition step 140. The volume to be machined 307 is preferably greater than or equal to the defect volume as shown in Fig. . For example, a first processor of the controller is configured to generate 147 a volume to be machined 307 based on the data provided during the contactless measurement.

The fifth step 155 is the machining of the object 305 by removing the volume to be machined 307. When this step is carried out by the repair system described below, a second processor of the controller generates 150 trajectories of the means for removing material based on the volume generated by the first processor. Once this machining step 155 is completed, the object 305 is described as machined or scoured.

According to one embodiment, the machining is carried out by milling, drilling and/or by cutting the defect 303.

Preferably, the marker 200 is made of an easily machinable material in order to be able to leave the marker 200 in place on the object 305 during the entire repair process. Advantageously, the use of polyether foam or polyurethane foam for the manufacture of the marker 200 makes it possible to manufacture a machinable marker 200 at low cost.

Alternatively, when the marker 200 is manufactured in a material that is difficult to machine, a step of removing the marker 200 may be necessary between the determination 140 of the position of the defects 303 and the volume to be machined 307 and the machining step 155.

The sixth step 165 is the reloading of the volume machined in the previous step by adding material. When this step 165 is carried out by the repair system described below, the second processor of the controller generates 160 trajectories of the material adding means based on the machined volume. The machined volume can be the volume calculated previously. Alternatively, the machined volume can be recalculated 163 as the intersection between the volume occupied by the machining means along its trajectory and the volume of the object 305 represented locally by its surface.

According to one embodiment, the reloading is carried out by additive manufacturing such as 3D printing such as material projection (“Material Jetting” in English) or a process from the “Directed Energy Deposition” family. in English) such as the powder projection process with laser fusion ("Laser Metal Deposition" - LMD - in English) also called "laser deposition" or wire deposition by electric arc ("WAAM - Wire Arc Additive Manufacturing" in English). Advantageously, laser deposition allows localized and rapid cooling of the reloading location. This type of deposit therefore makes it possible to obtain a particularly fine microstructure, thus providing superior mechanical properties and limiting thermal deformation of the object 305 to be repaired. Indeed, cooling by laser deposition is faster than by electric arc deposition and much faster than in conventional foundry. In addition, several powder reservoirs can be activated during reloading, which makes it possible to develop alloys adapted to the need and/or a gradient of materials in the case of a heterogeneous repair. Finally, laser deposition allows coaxial or lateral projection.

The method 100 may include an optional step 145 of determining a surface model of the defect zone. For example, the surface model can be previously encoded in the form of the marker 200 associated with the defect 303. Alternatively, the surface model is determined using the three-dimensional position, measured for example by three-dimensional scan, of at least three points on the surface of the object 305 around the defect 303. The surface model is then determined by an adjustment (“fit” in English) of the model parameters in order to reproduce as faithfully as possible the position of the all of said points on the surface of the object 305. Preferably, the adjustment is a robust adjustment, that is to say, not biased by measurement artifacts or by the defect 303 itself. For example, the adjustment is of the RANSAC type (“RANdom SAMple Consensus” in English). The surface can be modeled by a plane, a polynomial, or other. The type of model can be determined in advance by the operator. This optional step can be carried out before or after machining.

When a surface model is determined 145, the method may include an optional surface finishing step 180. This step 180 includes a first sub-step 183 of determining a surface of the defect zone after reloading the machined volume. For example, the three-dimensional position, measured by three-dimensional scanning, of at least three points on the surface of the object 305 in the defect area is determined. The surface thus measured is compared 185 to the surface model of the corresponding defect zone. Thus, the deviation between the measured surface and the surface model at the points whose three-dimensional position has been determined is measured. In places where the measured surface is in excess compared to the model (that is to say, when excess material has been deposited during reloading), an additional machining step 187 is carried out in order to get closer to the surface model. At locations where the measured surface is deficient in relation to the model (that is to say, when too little material has been deposited during reloading), an additional reloading step 187 is carried out in order to get closer to the surface model. .

Finally, the method may include an additional post-processing step 190 in order to restore the physical and/or chemical properties of the object 305 to the defect zone. Advantageously, this post-processing step 190 also makes it possible to restore the surface condition in the case of repairing an object 305 comprising a functional surface. This post-processing step 190 includes polishing (mechanical or laser), heat treatment and/or wave treatment (mechanical or acoustic) of the defect zone.

When the object 305 includes several defects 303, each of the steps of the method can be carried out sequentially or iteratively for each of the defects 303. That is to say that all of the steps of the method can be carried out for a defect 303 before to carry out all of the steps for the following fault 303 or that each step can be carried out on all of the faults 303 before moving on to the next step. A set of process steps can also, for example, be carried out sequentially before carrying out the rest of the steps iteratively. In this embodiment, several markers 200 from the set of pre-existing markers are selected, i.e. a marker 200 is selected for each surface defect 303, simultaneously or successively.

The present invention also relates to a system for repairing an object 305 presenting at least one surface defect 303.

• un ensemble de marqueurs tel que défini ci-dessus; et
• une machine de réparation comprenant ;
  • au moins un moyen d’enlèvement de matière ;
  • au moins un moyen d’ajout de matière ;
  • un moyen de mesure sans contact 301 configuré pour déterminer une position du défaut 303 sur l’objet 305 et des caractéristiques géométriques du défaut 303, lesdites caractéristiques géométriques comprenant au moins les deux dimensions de la surface du défaut 303 ; et
  • un contrôleur comprenant au moins :
    • un premier processeur configuré pour générer 147 un volume à usiner 307 et/ou un volume à recharger sur base des données fournies par le moyen de mesure sans contact 301 et de la position du défaut 303 fournie par le moyen de mesure sans contact 301 ; et
    • un deuxième processeur configuré pour générer des trajectoires des moyens d’enlèvement et/ou d’ajout de matière sur base du volume généré par le premier processeur.

Said system is configured to implement the repair method according to the invention and comprises:

• a set of markers as defined above; And
• a repair machine comprising;
  • at least one material removal means;
  • at least one means of adding material;
  • a contactless measuring means 301 configured to determine a position of the defect 303 on the object 305 and geometric characteristics of the defect 303, said geometric characteristics comprising at least the two dimensions of the surface of the defect 303; And
  • a controller comprising at least:
    • a first processor configured to generate 147 a volume to be machined 307 and/or a volume to be recharged based on the data provided by the contactless measuring means 301 and the position of the defect 303 provided by the contactless measuring means 301; And
    • a second processor configured to generate trajectories of the material removal and/or addition means based on the volume generated by the first processor.

The characteristics of the elements used in the process are those of the corresponding elements of the system.

The repair machine can also include a work space allowing, when the object 305 is positioned in this work space, to determine the coordinates of the object 305 in a reference coordinate system common with the different elements of the machine of repair. A common reference coordinate system is advantageous because it allows the marked object 305 to be positioned almost arbitrarily in the working space of the repair system (except that the defect zone is accessible and reasonably oriented for repair operations). contactless measurement 301, machining and reloading). This therefore avoids loss of time and precision when placing the object 305 in the workspace.

The at least one material removal means makes it possible to machine the defect 303 identified, that is to say to remove material from the surface (internal or external) of the defect 303. The at least one material removal means can be a milling cutter, a drill and/or a cutting machine allowing respectively milling, drilling and/or cutting of the defect 303. Advantageously, when several material removal means are present, each of the means material removal can be different (for example a milling cutter and a drill) allowing the simultaneous use of several tools.

The at least one means of adding material makes it possible to reload the machined defect, that is to say to add material in order to fill the machined volume up to the surface of the object 305. The at least one means of adding material can allow reloading by additive manufacturing (3D printing) such as material jetting (“Material Jetting” in English) or a process from the “Directed Energy Deposition” family » in English) such as the powder projection process with laser fusion (“Laser Metal Deposition” -LMD - in English) also called “laser deposition” or wire deposition by electric arc (“WAAM - Wire Arc Additive Manufacturing” in English). Advantageously, laser deposition allows localized and rapid cooling of the reloading location. This type of deposit therefore makes it possible to obtain a particularly fine microstructure, thus providing superior mechanical properties and limiting thermal deformation of the object 305 to be repaired. Indeed, cooling by laser deposition is faster than by electric arc deposition and much faster than in conventional foundry. In addition, several powder reservoirs can be activated during reloading, which makes it possible to develop alloys adapted to the need and/or a gradient of materials in the case of a heterogeneous repair. Finally, laser deposition allows coaxial or lateral projection.

The contactless measuring means 301 is configured to record data related to the position of the different elements in the work space. These data make it possible, for example, to determine the position on the object 305 of the at least one defect 303 to be repaired and the geometric characteristics of the defects 303 identified. The non-contact measuring means 301 can be chosen from the laser profilometer, the laser scanner, the three-dimensional scanner, the instantaneous three-dimensional imager, the radiographer and/or the tomograph. The choice of the non-contact measuring means 301 may imply a constraint on the material forming the marker(s). For example, when using the laser profilometer, reflective surfaces should be avoided.

The contactless measuring means 301 can be mounted (that is to say, fixed reversibly or not) on one of the material adding means or one of the material removing means.

The presence of a controller in the repair machine allows the repair of the object 305 using the CNC technique (numerical computer control) and/or the use of a robotic arm. The controller makes it possible to analyze the data recorded by the contactless measuring means 301 and/or to control the at least one means of adding or removing material. To do this, the controller includes at least two processors.

The first processor is configured to generate a volume to be machined 307 and/or a volume to be recharged on the basis of the data provided by the contactless measuring means 301.

The second processor is configured to generate trajectories of the material removal and/or addition means based on the volume generated by the first processor.

In the following, modules should be understood as functional entities rather than as physically distinct hardware components. They can therefore be materialized either as grouped in the same tangible and concrete component, or as distributed among several of these components. Likewise, each of these modules is possibly itself shared between at least two physical components. In addition, the modules are implemented in the form of hardware , software , firmware or any mixed form thereof. They are preferably incorporated in at least one processor of the system.

The system may further comprise a first module for generating a surface model of the object 305 based on the data provided by the contactless measuring means 301 and/or a second module for determining the position and dimensions of the marker 200 positioned.

DESCRIPTION OF FIGURES

Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the appended drawings which illustrate examples of embodiment devoid of any limiting character. In the figures:

represents the method of repairing an object according to one embodiment of the invention.

shows a sample of all the markers of a system for repairing an object according to one embodiment of the invention.

shows the positioning of a marker on a fault.

NUMERICAL REFERENCES

100 – Item Repair Method
110 – Determination of the position of the defect on the object,
120 – Marker selection
125 – Marker positioning
130 – Object Scan
140 – Marker Recognition
145 – Determination of a surface model
147 – Determination of a volume to be machined
150 – Generation of trajectories of material removal means
155 – Machining
160 – Generation of trajectories of material addition means
163 – Determination of the machined volume
165 – Reloading
180 – Finishing
183 – Determination of the surface of the defect zone
185 – Comparison with the surface model
187 – Addition or removal of material
190 – Post-processing
200 – Marker
301 – Non-contact measuring means
303 – Surface defect
305 – Purpose
307 – Volume to be machined

Claims (10)

Method (100) for repairing an object (305) presenting at least one surface defect (303), the method comprising the following steps:

1. determination (110) of the position of the defect (303) on the object (305), said defect (303) having an external surface, and geometric characteristics of the defect (303), said geometric characteristics comprising at least the two dimensions of the external surface of the defect (303) and a geometric shape of the defect (303);
2. selection (120) of a three-dimensional marker comprising at least one base whose dimensions are greater than or equal to those of the surface of the defect (303), said marker being chosen from a set of pre-existing markers;
3. positioning (125) of the selected marker on the object (305) so that the base of the marker covers at least the entire surface of the defect (303), the position, dimensions, and/or shape of the marker defining a fault volume and a fault zone;
4. determination (147) of a volume to be machined (307) according to the defect volume defined in step c);
5. machining (155) of the object (305) by removing the volume to be machined (307) determined in step d); And
6. reloading (165) of the volume machined in step e) by adding material.

Repair method (100) according to claim 1 , further comprising a step (145) of determining a surface model of the defect zone. Repair method (100) according to claim2, further comprising a surface finishing step (180) comprising the following steps:

• Determination (183), by three-dimensional scan, of a surface of the defect zone after reloading the machined volume;
• Comparison (185) of said surface with the surface model of the defect zone;
• machining or resurfacing (187) of the surface of the defect zone depending on the result of said comparison.

Repair method (100) according to any one of claims 1 to 3 , further comprising an additional post-treatment step (190) comprising polishing the surface of the defect zone, heat treatment of the defect zone , and/or treatment of the fault zone with mechanical or acoustic waves. Repair method (100) according to any one of claims 1 to 4 , in which the machining is carried out by milling, drilling and/or cutting. Repair method (100) according to any one of claims 1 to 5 , in which the resurfacing is carried out by additive manufacturing. Repair method (100) according to any one of claims 1 to 6 , in which the determination (110) of the position of the defect (303) on the object (305) and the dimensions of the surface of the defect (303) is carried out by non-contact measurement. Repair method (100) according to claim 7 , in which the non-contact measurement is chosen from laser profilometry, laser scanning, three-dimensional scanning, instantaneous three-dimensional imaging, radiography and/or tomography. Repair method (100) according to any one of claims 1 to 8 , in which the markers are made of a machinable material. System for repairing an object (305) presenting at least one surface defect (303), the system being configured to implement the repair method (100) according to any one of the claims1has9and including:

• a set of markers; And
• a repair machine comprising;
  • at least one material removal means;
  • at least one means of adding material;
  • non-contact measuring means (301) configured to determine a position of the defect (303) on the object (305) and geometric characteristics of the defect (303), said geometric characteristics comprising at least the two dimensions of the surface of the defect (303); And
  • a controller comprising at least:
    • a first processor configured to generate a volume to be machined (307) and/or a volume to be recharged based on the data provided by the contactless measuring means and the position of the defect (303) provided by the contactless measuring means; And
    • a second processor configured to generate (160) trajectories of the material removal and/or addition means based on the volume generated by the first processor.