Method for manufacturing an assemblable mechanical twin of a mechanical structure

Abstract

The invention relates to a method for manufacturing an assemblable mechanical twin of a first mechanical structure from a three-dimensional model of the first mechanical structure, referred to as the initial model, characterised in that the method comprises the following steps: - a step of determining a fractionation map of the initial model from at least one predetermined mechanical specification and from the geometry of the initial model; - a step of generating, from the fractionation map, a fractionation of the initial model into a plurality of 3D models, referred to as structural models, associated with assembly and attachment means, referred to as coupled assembly and attachment means; - a step of producing, from the plurality of structural models, a plurality of assemblable structural modules.

Description

[0001] DESCRIPTION

[0002] TITLE OF THE INVENTION: Method for manufacturing an assemblable mechanical twin of a mechanical structure

[0003] Technical field of the invention

[0004] The invention relates to methods for maintaining mechanical structures. More particularly, the invention relates to a method for manufacturing an assemblable mechanical twin of a mechanical structure.

[0005] Technological background

[0006] Mechanical structures used in various fields of engineering are, by nature, subject to mechanical stresses, such as tensile, compressive, shear, or torsional stresses, as well as impacts. These various stresses fatigue mechanical structures and can cause deformations, tears, cracks, or even ruptures. These defects, even partial ones, can be the cause of more significant structural problems that compromise the overall safety of the structure.

[0007] When structural problems arise in a mechanical structure, it is important to carry out the necessary repairs. Maintaining mechanical structures inevitably involves an economic cost, often not insignificant. Furthermore, if the mechanical structure needs to be replaced regularly, the associated cost will be even higher.

[0008] A well-known way to reduce the production costs of structures is to use additive manufacturing, which allows for the creation of structures with complex geometries without difficulty. The main drawback of this type of solution is the impossibility of manufacturing mechanical structures of arbitrarily large size, the maximum size being that of the 3D printer.

[0009] Furthermore, even if the maximum size defect is set aside, it is clear that if the manufactured mechanical structure is damaged in a small area, the entire structure will still have to be replaced.

[0010] An additional drawback of existing additive manufacturing methods is the impossibility of reinforcing the mechanical structure at the level of the parts most mechanically stressed or needing to resist impacts.

[0011] Furthermore, in the case where the production of a large structure does not pose a difficulty, the transport of the latter can nevertheless prove to be complex, costly and can give rise to collateral damage, such as deformation, breakage or even general deterioration of the structure.

[0012] Objectives of the invention

[0013] There is therefore a need for a method of manufacturing a mechanical twin that allows the manufacture of structures of arbitrary size while ensuring optimal mechanical strength.

[0014] There is also a need for a method of manufacturing a mechanical twin as described above and making it possible to simplify the transport of said mechanical twins, in particular by reducing the packaging volume and resistance to damage during transport.

[0015] There is also a need to reduce the production costs of the said mechanical twin.

[0016] The invention is placed in this context and aims to resolve one or more of the aforementioned drawbacks.

[0017] The invention aims to provide a method for manufacturing an assemblable mechanical twin of a mechanical structure, without size restrictions on said structure, and offering optimal mechanical resistance of said mechanical twin.

[0018] Statement of the invention

[0019] To do this, the invention relates to a method for manufacturing an assemblable mechanical twin of a first mechanical structure from a three-dimensional model, called the initial model, of said first mechanical structure.

[0020] The method for manufacturing the assemblable mechanical twin is characterized in that it comprises the following steps: a step of determining a splitting map of said initial model from a predetermined mechanical specification and the geometry of said initial model; a step of generating, from said splitting map, a splitting of said initial model into a plurality of three-dimensional models, called structural models, associated with assembly and fixing means, called coupled assembly and fixing means; a step of producing, from said plurality of structural models, a plurality of assemblable structural modules.

[0021] By doing so, the invention proposes to produce an assemblable mechanical twin of said first mechanical structure through a plurality of assemblable structural modules specially designed to meet said predetermined mechanical specification.

[0022] The aforementioned predetermined mechanical specification may be given, for example, in the form of values ​​or ranges of values, of one or more information from the group comprising: mass density, Lamé parameter, Poisson's ratio, P-wave modulus, shear modulus, Young's modulus, tensile strength, resilience, yield strength, breaking stress, hardness, ductility, toughness, fatigue strength, compressive strength, shear strength, stiffness, modulus of elasticity, vibration damping, shock resistance, thermal expansion, thermal conductivity, corrosion resistance, wear resistance, high temperature resistance, low temperature resistance, radiation resistance, permeability, porosity, etc.

[0023] For example, in the case of the mass density of the mechanical structure, the mass density of the structure is a scalar function with positive real values ​​and defined on a compact subset of the real three-dimensional space, it is commonly mathematically denoted M(x,y,z), where (x,y,z) are the three spatial coordinates of a point. Thus, the predetermined mechanical specification can be given by an inequality of the form dxdydz > k, where k is a predetermined positive value of mass and 11 a compact set of M 3 .

[0024] Said initial model is a three-dimensional model of said first mechanical structure and has, by nature, the same geometry as said first mechanical structure.

[0025] The fractionation map of said initial model is determined so as to satisfy a predetermined mechanical specification and makes it possible to define a geometric fractionation of said initial model. This predetermined mechanical specification is a mechanical requirement, in particular qualitative and / or quantitative, which must be satisfied by said assemblable mechanical twin. Due to the nature of the predetermined mechanical specification, the fractionation map may in particular consist of a plurality of general two-dimensional manifolds, in particular non-planar ones.

[0026] The splitting map precisely defines the geometric sub-parts of said initial model which are used to define the structural models.

[0027] Said plurality of structural models thus constitutes a splitting of said initial model in the sense that, on the one hand, said initial model is equal to the set-theoretic union of the structural models and, on the other hand, the structural models define two-by-two disjoint geometric sets.

[0028] According to these aspects of the invention, said structural modules are fabricated from said plurality of structural models, thereby producing an assemblable mechanical twin of said first mechanical structure.

[0029] Furthermore, the structural modules include means of assembly and fixing, as do the structural models from which they are derived, and allow for simple, very strong and rapid assembly.

[0030] The assembly means may in particular be tabs and / or housings capable of receiving said tabs.

[0031] If desired, the joining means may also consist of slats, dowels, joints, tabs, dowels, tenons and mortises, etc.

[0032] Advantageously, said assembly means are capable of cooperating mechanically with the fixing means so as to allow the assembly and fixing of said plurality of structural modules.

[0033] Advantageously, said assembly and / or fixing means comprise structures, in particular housings, capable of receiving external fixing means.

[0034] External fastening means may include rivets, screws, nails, nuts and bolts, clamps, dowels, staples, adhesives, Velcro fasteners, as well as solutions such as glue, sealant, heat sealing, heat welding, etc.

[0035] Advantageously, said plurality of structural modules can be arranged in a packaging with a volume of advantage reduced compared to that which would be necessary to package said first mechanical structure in its entirety.

[0036] In the context of the present invention, a three-dimensional model is understood to mean a three-dimensional digital representation of a mechanical structure accurately reflecting the physical characteristics of the structure, in particular its geometry and in particular its shape and dimensions, as well as elements such as points, lines, surfaces and volumes of said structure. Three-dimensional models are commonly in the form of meshes consisting of polyhedral elements. The aforementioned meshes may in particular be structured meshes, unstructured meshes or a combination of structured and unstructured meshes.

[0037] If desired, the three-dimensional model can incorporate details about the physical properties of the structure, such as constituent materials, color, texture, and reflectivity.

[0038] In an advantageous embodiment of the invention, the step of determining a fractionation map of said initial model comprises a sub-step of determining a mechanical quality on said initial model from the predetermined mechanical specification.

[0039] By determining this mechanical quality, this sub-step makes it possible to establish, on the basis of a detailed analysis of structural mechanics, a splitting map of the initial model to ensure that the assemblable mechanical twin, once produced, satisfies all the mechanical specifications.

[0040] Advantageously, said mechanical quality can be chosen, for example, from the group comprising: displacements, deformations, compression, extension, rotation, torsion, reactions to supports, bending moment, shear forces, stability, buckling, impacts, dynamic loads, structural dynamics, vibrations, material fatigue, residual stresses, thermal expansions, natural modes, stress concentration, etc.

[0041] By way of non-limiting example, said predetermined mechanical specification may be an interval of values ​​of the displacements of the initial model, generated by the influence of a plurality of forces applied to said model.

[0042] In this non-limiting example, the associated mechanical quality is the set of displacements in the three spatial directions. The values ​​of said displacements at the point of spatial coordinates x,y,z) are commonly noted:

[0043] [Math. 1] u(x, y, z), vx, y, z), w(x, y, z)

[0044] Thus, by noting U the displacement vector whose components are (u,v,w) (in meters); F the applied force density (in Newtons per cubic meter); S the stress tensor (in Pascal); M the mass density (in kilograms per cubic meter); the equilibrium equations are then given by:

[0045] [Math. 2]

[0046] The equilibrium equations are supplemented by initial conditions and / or boundary conditions adapted to the determination of said mechanical quality.

[0047] In a cumulative embodiment of the invention, the step of determining a splitting map of said initial model comprises a sub-step, consecutive to said sub-step of determining a mechanical quality on said initial model, of determining a plurality of surfaces, called cutting surfaces, of said initial model from said mechanical quality. The determination of the plurality of cutting surfaces is carried out by taking into account the information from the mechanical quality so as to validate the predetermined mechanical specification. By proceeding in this way it is then possible to ensure that the assemblable mechanical twin satisfies said predetermined mechanical specification.

[0048] Cutting surfaces are two-dimensional manifolds, including differential manifolds that are not necessarily planar.

[0049] If desired, the cutting surfaces may be surfaces defined, in particular, by parametric and / or implicit and / or explicit mathematical equations.

[0050] Alternatively, the cutting surfaces may be surfaces defined by Boolean mathematical expressions, in particular defined through union and / or intersection and / or complement operators.

[0051] Alternatively, the cutting surfaces may be surfaces defined by meshes, in particular two-dimensional meshes, in particular using triangular faces.

[0052] In a cumulative embodiment of the invention, the step of determining a splitting map of said initial model comprises a sub-step, following said sub-step of determining a plurality of cutting surfaces, of generating a splitting map of said initial model from said plurality of cutting surfaces and said initial model.

[0053] According to this advantageous embodiment, the splitting map is given by the set of cutting surfaces positioned on said initial model. Said set of cutting surfaces spatially splits said three-dimensional model into a plurality of sub-models.

[0054] In an advantageous embodiment of the invention, said step of generating, from said splitting map, a splitting of said initial model into a plurality of structural models associated with assembly and fixing means comprises the following sub-steps: a sub-step of generating said plurality of structural models from said initial model and said splitting map; a sub-step of coupling, on each model of said plurality of structural models, assembly and fixing means, called coupled assembly and fixing means.

[0055] According to this advantageous embodiment, the structural models are generated from said splitting map acting on said initial model. In particular, the cutting surfaces make it possible to subdivide said initial model into the plurality of structural models by defining sub-regions of the model whose edges are defined by said cutting surfaces.

[0056] By proceeding in this way, the invention advantageously proposes to integrate, on each structural model, assembly and fixing means; this characteristic makes it possible, during the production stage, to obtain structural modules integrating said assembly and fixing means.

[0057] Preferably, the splitting card is designed to define, from its design, the geometries corresponding to said assembly and fixing means.

[0058] Advantageously, the fixing means may be, for example, tabs, in particular tabs comprising holes capable of receiving external fixing means, such as, for example, rivets.

[0059] Other non-limiting examples of the fastening means are housings, in particular housings having holes capable of receiving external fastening means, such as, for example, rivets.

[0060] As a non-limiting example of the advantageous embodiment, two structural models comprise complementary assembly means; for example, one comprises a tab and the other comprises a housing capable of receiving said tab. If desired, said tab and said housing comprise fixing means in the form of coaxial cylinders defining cylindrical housings at said tab and said housing; said cylindrical housings are capable of receiving an external fixing means, in particular a rivet. Advantageously, said coupled fixing means are capable of receiving external fixing means, capable of mechanically cooperating with said coupled assembly and fixing means, so as to ensure the maintenance of the assemblable mechanical twin once assembled; as well as so that said mechanical twin satisfies the predetermined mechanical specification.

[0061] In an advantageous embodiment of the invention, said step of splitting said initial model into a plurality of structural models associated with assembly and fixing means comprises a sub-step and not necessarily consecutive to the sub-step of generating, for at least one module of said plurality of structural modules, a network of mechanical structures extending over at least one internal sub-part of the at least one module.

[0062] According to this advantageous embodiment, the mechanical structure network makes it possible to reduce the total mass of the mechanical twin without compromising the strength of the latter.

[0063] If desired, the network of structures may take the form of a set of internal walls of at least one model and / or module of said plurality of structural models and / or modules. Said walls may have various geometries and may in particular be walls with rectilinear filling; honeycomb filling, triangular filling, gyroid filling, adaptive filling, etc.

[0064] In an advantageous embodiment of the invention, the method for manufacturing an assemblable mechanical twin is characterized in that it comprises a step, following the step of producing a plurality of assemblable structural modules, of assembling said plurality of structural modules into an assembly constituting a second mechanical structure, called a mechanical twin, physically reproducing said first mechanical structure.

[0065] This step allows, starting from the structural modules, to assemble them in order to obtain a second mechanical structure, namely the mechanical twin of said first mechanical structure. In addition, said second mechanical structure satisfies the predetermined mechanical specification. If desired, the structural modules include order and / or sequencing and / or location indicators relative to other modules making it possible to know the order in which the modules must be assembled. For example, such indicators can in particular be incorporated directly into the body of said modules and be provided from the three-dimensional modeling step of the corresponding models. Other indicators can be provided such as colors, stickable labels, engravings of any type of graphic symbol, such as arrows, numbers, etc.

[0066] In an advantageous embodiment of the invention, the step of producing structural modules is carried out by 3D printing.

[0067] This feature allows the production of complex geometries and allows the low-cost structural modules to be obtained in a wide variety of distinct materials.

[0068] If desired, 3D printing can be achieved through additive manufacturing by extrusion of material, by printing on photosensitive resins or any other 3D printing process.

[0069] According to this advantageous embodiment, the 3D printer can print in one or more materials from the following non-limiting list: polylactic acid, polyether-ether-ketone, acrylonitrile butadiene styrene, glycolized polyethylene terephthalate, thermoplastic polyurethane, aluminum, copper, steel, concrete, nylon, polyvinyl alcohol, acrylonitrile styrene acrylate, high impact polystyrene, mixtures of polylactic acid and wood particles, metal (including stainless steel, titanium and aluminum), resin, ceramic, color gradient filaments, polycarbonate, polypropylene, carbon fiber, electrically conductive filaments, magnetic filaments, luminescent filaments, thermochromic filaments, or biocompatible materials, such as silicones.

[0070] In an advantageous embodiment of the invention, the step of producing structural modules comprises a sub-step of producing supports, called printing supports, capable of stabilizing the structure of at least one module of said plurality of structural modules. This characteristic makes it possible to ensure optimal printing of said structural modules. Indeed, the printing supports play a role of mechanical stabilizers during the printing process.

[0071] Advantageously and according to the invention, the method comprises a preliminary step of manufacturing an assemblable mechanical twin characterized in that it comprises a preliminary step of creating a three-dimensional model of said first mechanical structure.

[0072] This step of creating the three-dimensional model of the first mechanical structure makes it possible to define the initial model on which the structural models will be determined.

[0073] The three-dimensional model can be created, in particular, by computer-aided design software or by direct scanning of the first mechanical structure.

[0074] In an advantageous embodiment of the invention, the step of creating said three-dimensional model comprises a sub-step of scanning said first mechanical structure.

[0075] By doing this, it is possible to generate three-dimensional models of the said first mechanical structure that are faithful to reality and with high definition.

[0076] Advantageously and without restriction of generality, different scanning techniques can be used, in particular techniques using a LIDAR scanner.

[0077] In an advantageous embodiment of the invention, said first mechanical structure is an automotive structure.

[0078] This feature, according to the invention, makes it possible to produce assemblable mechanical twins of any automobile structure; in particular bumpers, doors, hoods, roofs, etc.

[0079] In an advantageous embodiment of the invention, the method for manufacturing an assemblable mechanical twin further comprises a step, following the step of producing a plurality of structural modules, of manufacturing at least one mold of at least one structural module capable of reproducing said structural module by a molding method.

[0080] The invention also relates to a mechanical twin of a mechanical structure, comprising a plurality of structural modules, and obtained by the method of manufacturing an assemblable mechanical twin described above.

[0081] List of figures

[0082] Other aims, characteristics and advantages of the invention will appear on reading the following description given solely for non-limiting purposes and which refers to the appended figures in which:

[0083] [Fig. 1] is a schematic view of a method of manufacturing an assemblable mechanical twin of a mechanical structure according to one embodiment of the invention.

[0084] [Fig. 2] is a schematic view of a motor vehicle comprising a first mechanical structure.

[0085] [Fig. 3] is a schematic perspective view of a first mechanical structure.

[0086] [Fig. 4] is a triplet of schematic perspective views of a three-dimensional model of a first mechanical structure and a plurality of cutting surfaces according to one embodiment of the invention.

[0087] [Fig. 5] is a schematic perspective view of a structural model comprising assembly and fixing means according to one embodiment of the invention.

[0088] [Fig. 6] is a quadruplet of schematic views of a structural model comprising assembly and fixing means according to one embodiment of the invention.

[0089] [Fig. 7] is a view of a pair of structural models comprising assembly and fixing means according to one embodiment of the invention.

[0090] [Fig. 8] is a triplet of graphs representing mechanical qualities of a part of a structural model according to an embodiment of the invention.

[0091] [Fig. 9] is a schematic perspective view of a network of mechanical structures on an interior portion of a structural module according to one embodiment of the invention.

[0092] Detailed description of an embodiment of the invention

[0093] In the figures, scales and proportions are not strictly respected, for the purposes of illustration and clarity.

[0094] Furthermore, identical, similar or analogous elements are designated by the same references in all figures.

[0095] Figure 1 represents, schematically and partially, a method of manufacturing an assemblable mechanical twin of a first mechanical structure 1 according to the invention.

[0096] Said first mechanical structure is a door 1 of a motor vehicle 100.

[0097] The method begins with a preliminary step PI of creating a three-dimensional model 2 of said first mechanical structure 1.

[0098] Step PI of creating said three-dimensional model 2 comprises a sub-step P 1.1 of scanning, by a LIDAR scanner, said first mechanical structure 1.

[0099] Step PI is followed by a step E1 of determining a fractionation map 4 of said initial model 2 from a predetermined mechanical specification and the geometry of said initial model 2.

[0100] Step E1 of determining a fractionation map comprises a sub-step E1.1 of determining a mechanical quality on said initial model 2 from a predetermined mechanical specification.

[0101] In this exemplary embodiment, the mechanical quality is the deformation displacement of said initial model 2 and the predetermined mechanical specification indicates that the value of said displacement must be less than a threshold of 1 cm per spatial direction.

[0102] Sub-step El.l is followed by a sub-step El.2 of determining a plurality of surfaces 3.1; 3.2, called cutting surfaces, of said initial model 2 from said mechanical quality. Said cutting surfaces are non-planar two-dimensional differential varieties defined by parametric equations, with parameters (p,q) of the form:

[0103] [Math. 3] x = fi(p,qy = f2(.P, q), z = f3(p, q) , and f3 are scalar functions of two real variables.

[0104] Sub-step El.2 is followed by a sub-step El.3 of generating a splitting map 4 of said initial model 2 from said plurality of cutting surfaces 3.1; 3.2 and said initial model 2.

[0105] The fractionation map 4 of said initial model 2 is determined so as to satisfy the predetermined mechanical specification and makes it possible to define a geometric fractionation of said initial model 2.

[0106] The splitting map is given by the set of cutting surfaces 3.1; 3.2 positioned on said initial model 2. Said set of cutting surfaces 3.1; 3.2 spatially splits said three-dimensional model 2 into a plurality of sub-models 5.

[0107] Following step E1, the method comprises a step E2 of generating, from said fractionation map 4, a fractionation of said initial model 2 into a plurality of three-dimensional models, called structural models 5, associated with assembly means 6.1; 6.2 and fixing means 7, called coupled assembly and fixing means;

[0108] Step E2 comprises a first sub-step E2.1 of generating said plurality of structural models 5 from said initial model 2 and said fractionation map 4.

[0109] The structural models 5 are generated from said splitting map 4 acting on said initial model 2. In particular, the cutting surfaces 3.1; 3.2 make it possible to subdivide said initial model 2 into the plurality of structural models 8 by defining sub-regions of the initial model 2 whose edges are defined by said cutting surfaces 3.1; 3.2. The sub-step E2.1 is followed by a sub-step E2.2 of coupling, on each model 5 of said plurality of structural models, assembly means 6.1; 6.2 and fixing means 7.

[0110] The assembly means are tabs 6.1 and housings 6.2 capable of receiving the tabs 6.1.

[0111] The tabs 6.1 and at least one of the walls bordering said housings 6.2 comprise fixing means 7 in the form of a cylindrical hole capable of receiving external fixing means, in particular rivets.

[0112] The external fixing means are capable of mechanically cooperating with the assembly means 6.1; 6.2 so as to ensure the maintenance of the assemblable mechanical twin once assembled and ensure that the mechanical twin meets the predetermined mechanical specification.

[0113] Sub-step E2.2 is followed by a sub-step E2.3 of generating, for at least one module 8 of said plurality of structural modules, a network of mechanical structures 19 extending over at least one internal sub-part of said at least one module 8.

[0114] The network of mechanical structures 19 has the shape of a set of internal walls, in grid-like filling geometry, in each model 5 of said plurality of structural models.

[0115] Following step E2, the method comprises a step E3 of producing, from said plurality of structural models 5, a plurality of assemblable structural modules 8.

[0116] This production step is carried out by additive manufacturing by extrusion of polylactic acid material using a 3D printer.

[0117] Step E3 comprises a first sub-step E3.1 of producing printing supports (not shown), capable of stabilizing the structure of at least one module 8 of said plurality of structural modules. Said printing supports make it possible to ensure optimal printing of said structural modules. The material of said printing supports is water-soluble. The method concludes with a step E4, following step E3 of producing a plurality of assemblable structural modules 8, of assembling said plurality of structural modules 8 into an assembly constituting a second mechanical structure, called a mechanical twin, physically reproducing said first mechanical structure 1.

[0118] This assembly step consists in particular of assembling the different structural modules 8 using the assembly means 6.1; 6.2 and fixing means 7 using external fixing means, in particular in the form of rivets.

[0119] The structural modules include order indicators 11 in the form of numbers engraved on said modules and making it possible to know the order in which the modules must be assembled.

[0120] Upon finalizing the assembly of said structural modules, the assemblable mechanical twin of the first mechanical structure is finalized.

[0121] Figure 2 shows, schematically and partially, a motor vehicle 100 comprising a first mechanical structure 1 consisting of a door of said vehicle 100.

[0122] Figure 3 represents, schematically and partially, a three-dimensional model 2 of a first mechanical structure 1 obtained by scanning with a LIDAR scanner of a door of a motor vehicle 100.

[0123] Figure 4 represents, schematically and partially, a three-dimensional model 2 of a first mechanical structure 1 as well as a plurality of cutting surfaces 3.1 and a plurality of cutting surfaces 3.2, constituting a fractionation map 4 of said initial model 2 according to an embodiment of the invention.

[0124] Figure 5 shows, schematically and partially, a perspective view of a structural model 5 obtained using the splitting map of Fig. 4 and obtained according to step E2 of the method of Fig. 1. Said structural model 5 comprises assembly means 6.1; 6.2 and fixing means 7 in the form of tabs and housings, according to one embodiment of the invention. Said structural model 5 also comprises assembly order indicators in the form of numbers present directly on the model 5.

[0125] The structural model includes a hole 12 constituting an area of ​​interest and for which a predetermined mechanical specification was given in step E1.

[0126] Figure 6 shows, schematically and partially, a perspective view, a top view and two front views of a structural model 5 comprising assembly means 6.1; 6.2 and fixing means 7 in the form of tabs 6.1; 6.2 and housings 7, according to one embodiment of the invention.

[0127] The system illustrated in Figure 6 implements an arrangement of male tabs (6.1) and female housings (6.2), intended to facilitate the modular assembly of a mechanical twin. Each structural model 5 comprises several of these assembly means distributed on its lateral faces, according to a geometry adapted to precise engagement.

[0128] The tabs 6.1 are designed to fit precisely into the corresponding housings 6.2, so as to ensure a stable and geometrically constrained fit. In order to improve the mechanical strength of the assembly once assembled, fixing means 7, such as cylindrical through holes, are provided both on the tabs 6.1 and on at least one wall bordering the housings 6.2. These holes are sized to receive external fixing means, typically rivets, thus ensuring secure mechanical locking after insertion.

[0129] The arrangement of the tabs and housings has a homogeneous distribution on the edges of the model 5, which allows assembly repeatability while minimizing clearances and tolerances. By combining these assembly elements with external fixing means, the system guarantees increased structural stability, allowing the final mechanical twin to achieve a predetermined mechanical specification, particularly in terms of resistance to mechanical stresses.

[0130] This modular system thus allows not only simple and rapid assembly, but also reversible if necessary, while ensuring excellent structural locking once the elements are fixed. The structural models 5 are provided, on their lateral edges, with a tongue and housing assembly system distributed in a symmetrical and functional manner. Each model 5 comprises, on two opposite sides, tongues 6.1 projecting outwards, while the other two opposite sides comprise housings 6.2 formed in a hollow and sized to receive said tongues 6.1. Thus, each model can be coupled with an adjacent model by cross-fitting, where the tongues of one model are inserted into the housings of a neighboring model.

[0131] The tabs 6.1 are parallelepipedal in shape and extend orthogonally to the main wall of the model 5. They are positioned equidistantly along the edge of the model, which allows for a regular distribution of mechanical forces during assembly. The housings 6.2, for their part, have a shape complementary to the tabs, with an outwardly opening hollow, bordered by rigid walls serving to guide and hold the inserted tab.

[0132] Each tab 6.1 is provided with a cylindrical through hole, generally centered, intended to receive a fastening means 7 such as a rivet. Correspondingly, at least one of the internal side walls of the housings 6.2 also has an aligned through hole, so that once the tab is inserted, the two holes are coaxial, allowing the passage of the fastening means. This double mechanical and geometric alignment ensures rigid locking of the assembly, preventing any involuntary disengagement.

[0133] This cross-organization of the assembly means—tabs on certain edges, housings on opposite edges—also allows for optimal modularity, with each model designed to easily couple with its neighbors according to a regular grid. The system thus promotes rapid assembly, without the need for particular orientation, while ensuring reliable structural stability once the fastening means are in place.

[0134] Figure 7 shows, schematically and partially, a top view of two structural models capable of being assembled along the direction of the section AA. Figure 7 also shows two sectional views of the pair of structural models along two section directions AA and BB.

[0135] Each structural model 5 comprises assembly means in the form of tabs 6.1 and housings 6.2, as well as fixing means 7, according to one embodiment of the invention.

[0136] Figure 8 represents, schematically and partially, three graphs of three distinct mechanical qualities and calculated in a neighborhood of a hole 12, of a structural model 5, constituting a zone of interest according to a predetermined mechanical specification requiring that the spatial deformations be at most 1 cm in each spatial direction was given in step El.

[0137] Graph 20.1 represents the displacement by elastic deformation of a part of the initial model 2 around said hole 12. A part of the zone 15 around said hole 12 without deformation and the zone deformed by a compressive force exerted on said initial model 2 and modifying said zone 15 into a deformed zone 16 are represented. The result is obtained by numerical resolution of the equilibrium equations by a finite element method on a computer.

[0138] Figure 20.2 represents the displacement vector field 17 also obtained by numerically solving the equilibrium equations by a finite element method on a computer.

[0139] Figure 20.3 corresponds to the von Mises stress surface established from the numerical solution of the equilibrium equations by a finite element method on a computer.

[0140] Figure 9 represents, schematically and partially, a network of mechanical structures 19 in the form of walls arranged in a grid pattern inside a structural module 8 as described in sub-step E2.3.

[0141] The invention is not limited to the embodiments described. In particular, it could be provided to use the plurality of structural modules of said assemblable digital twin to manufacture molds of said structural modules subsequently used to reproduce said structural modules. Furthermore, the method for manufacturing a mechanical twin of a mechanical structure can be implemented by an embedded computer program product, for example, in a controller of a 3D printer, or in an external computing device used by 3D printers.

Claims

CLAIMS 1. Method for manufacturing an assemblable mechanical twin of a first mechanical structure (1) from a three-dimensional model (2) of said first mechanical structure (1), called initial model, characterized in that it comprises the following steps: a step (El) of determining a splitting map (4) of said initial model (2) from at least one predetermined mechanical specification and the geometry of said initial model (2); a step (E2) of generating, from said splitting map (4), a splitting of said initial model (2) into a plurality of three-dimensional models, called structural models (5), associated with assembly means (6.1; 6.2) and fixing means (7), called coupled assembly and fixing means; a step (E3) of producing, from said plurality of structural models (5), a plurality of assemblable structural modules (8).

2. A method of manufacturing an assemblable mechanical twin according to claim 1, characterized in that said step (El) of determining a splitting map (4) of said initial model (2) comprises the following sub-steps: a sub-step (El.l) of determining at least one mechanical quality on said initial model (2) from the at least one predetermined mechanical specification; a sub-step (E1.2) of determining a plurality of surfaces (3.1; 3.2), called cutting surfaces, of said initial model (2) from said at least one mechanical quality; a sub-step (El.3) of generating a splitting map (4) of said initial model (2) from said plurality of cutting surfaces (3.1; 3.2) and said initial model (2).

3. Method for manufacturing an assemblable mechanical twin according to one of claims 1 to 2, characterized in that said step (E2) of generating, from said splitting map (4), a splitting of said initial model (2) into a plurality of structural models (8) associated with assembly means (6.1; 6.2) and fixing means (7) comprises the following sub-steps: a sub-step (E2.1) of generating said plurality of structural models (5) from said initial model (2) and said splitting map (4); a sub-step (E2.2) of coupling, on each model (5) of said plurality of structural models, assembly means (6.1; 6.2) and fixing means (7).

4. Method for manufacturing an assemblable mechanical twin according to claim 3, characterized in that said step (E2) of generating a splitting of said initial model (2) into a plurality of structural models (5) associated with assembly means (6.1; 6.2) and fixing means (7) comprises a sub-step (E2.3), consecutive to said step (E2.1) and not necessarily consecutive to the sub-step (E2.2) of generating, for at least one module (8) of said plurality of structural modules, a network of mechanical structures (19) extending over at least one internal sub-part of said at least one module (8).

5. Method for manufacturing an assemblable mechanical twin according to one of claims 1 to 4, characterized in that it comprises a step (E4), following the step (E3) of producing a plurality of assemblable structural modules (8), of assembling said plurality of structural modules (8) into an assembly constituting a second mechanical structure, called mechanical twin, physically reproducing said first mechanical structure (1).

6. Method for manufacturing an assemblable mechanical twin according to one of claims 1 to 5, characterized in that the step (E3) of producing structural modules (8) is carried out by 3D printing.

7. Method for manufacturing an assemblable mechanical twin according to claim 6, characterized in that the step (E3) of producing structural modules (8) comprises a sub-step (E3.1) of producing supports, called printing supports, capable of stabilizing the structure of at least one module (8) of said plurality of structural modules.

8. Method for manufacturing an assemblable mechanical twin according to one of claims 1 to 7, characterized in that it comprises a preliminary step (PI) of creating a three-dimensional model (2) of said first mechanical structure (1); said preliminary step (PI) being implemented prior to said step (El) of determining a fractionation map (4).

9. Method for manufacturing an assemblable mechanical twin according to claim 8, characterized in that the step (PI) of creating said three-dimensional model (2) comprises a sub-step (Pl.1) of scanning said first mechanical structure (1).

10. Method for manufacturing an assemblable mechanical twin according to one of claims 1 to 9, characterized in that said first mechanical structure (1) is a structure of a motor vehicle.

11. Method for manufacturing an assemblable mechanical twin according to one of claims 1 to 10, characterized in that it further comprises a step of manufacturing at least one mold of at least one structural module capable of reproducing said structural module by a molding process.

12. Mechanical twin of a mechanical structure obtained by a manufacturing method according to one of claims 1 to 11.

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