Device for retaining individual elementary components

Abstract

Title: Device for retaining individual elementary components. Device comprising a voxel structure (11) and an envelope (12) encompassing the structure, forming, stacked along a so-called stacking direction (z), at least a first (1) and a second (2) level comprising respectively a first (121) and a second (122) envelope section comprising respectively a first (1211) and a second (1222) housing each comprising side walls (1211a), respectively a first (111) and a second (112) sets of voxels, each comprising side faces (113) joining a first (114) and a second (115) opposite face, the first and second housings receiving the first and second sets, the side walls of the first and second housings being configured to retain the side faces of the first and second sets,The levels are stacked so that the second face of the first set and the first face of the second set are at least partially in contact, forming a single-piece structure. Figure for the abbreviation: Fig. 1.

Description

Title of the invention: Device for holding individual elementary components Technical field

[0001] The present invention relates to the field of three-dimensional printing, but preferably four-dimensional printing, known as 4D printing. 4D printing makes it possible to print individual elementary components or voxels that actively respond to external stimuli. More specifically, it relates to improving the position retention of voxels made of active and / or passive materials. STATE OF THE ART

[0002] 4D printing technology is known from the state of the art. 4D printing is generally limited to printing, using an additive manufacturing process, 4D objects from a single active material under external stimulation, making the structure flexible and unwilling to satisfy high mechanical constraints.

[0003] Therefore, 4D printing consists of printing objects that can change shape and / or properties under the effect of energy stimulation. This energy stimulation can, for example, be achieved by a solvent, humidity, light, temperature, an electric field or even a magnetic field. To produce these objects, the technology involves the use of additive manufacturing processes and active or so-called "intelligent" materials.

[0004] To achieve performances approaching those of traditional actuators on the market, this technology necessarily requires mastery of multi-material printing. However, this capacity is currently limited by three-dimensional processes that allow certain couplings. To take into account the desire to produce objects composed of similar and dissimilar materials, it is appropriate to use several additive manufacturing processes and therefore to cover this technique as a technique for assembling prefabricated heterogeneous elements. Thus, it is appropriate to hybridize the printing techniques and to associate them with assembly and / or bonding operations, advantageously by robotic means.

[0005] One way to achieve this goal is through gluing, but if poorly selected or poorly positioned, adhesives can be a hindrance for multi-purpose applications, as they can limit the durability of the assemblies. In addition, glues play a role in controlling the desired changes in the shape of the assemblies. Glues also do not allow the use of all types of materials that one might wish to employ. Finally, the gluing process can be irreversible and prohibit disassembly and recovery / reuse of the prefabricated elements. individually.

[0006] In this direction, document US2015217459 Al discloses a solution for assembling individual elements called multi-material “soft robots” that can be likened to voxels.

[0007] In this solution, the shape of the flexible robots allows for easy assembly, which can be either manual or robotic. This cutting advantageously allows for reuse of the flexible robots in several solutions.

[0008] However, this assembly does not allow for continuous external surfaces. In addition, the holding of the flexible robots together during static or dynamic stresses may be insufficient. Indeed, phenomena of delamination or detachment of the voxels may be observed despite a punctual holding between the individual elements.

[0009] An object of the present invention is therefore to propose an improved solution for maintaining the position of voxels made of active and / or passive materials.

[0010] Other objects, features and advantages of the present invention will become apparent from the following description and accompanying drawings. It is understood that other advantages may be incorporated. SUMMARY

[0011] To achieve this objective, according to a first aspect, a device is provided comprising a voxel structure having at least one voxel based on an active material being configured so that said voxel is activated under external or internal energy stimulation.

[0012] The device is characterized in particular in that it comprises an envelope encompassing at least part of the structure, the envelope and the structure forming, stacked in a so-called stacking direction (z), at least a first and a second level comprising: - respectively a first envelope section and a second envelope section respectively comprising a first housing and a second housing each comprising side walls extending over a height h in the stacking direction, - respectively a first set of at least one voxel and a second set of at least one voxel, each comprising lateral faces extending in the stacking direction, the lateral faces joining a first face and a second face opposite in the stacking direction, the first housing receiving the first set of at least one voxel, the second housing receiving the second set of at least one voxel, the side walls of the first and second housing being configured to hold in position respectively the side faces of the first and second sets of at least one voxel, the levels being stacked such that the second face of the first set of at least one voxel and the first face of the second set of at least one voxel are at least partially in contact so as to form a single-piece assembly of the structure.

[0013] While current techniques direct those skilled in the art towards optimizing the positioning of voxels by passive global and internal maintenance, the invention claimed here proposes an effective, active and external solution that is easily achievable.

[0014] The device thus comprises both a single-piece structure composed of a plurality of sets of voxels composed of active and passive materials, but also a functional external envelope encompassing this structure. The latter which can be connected to each other by gluing and by obstacle, by a mechanical link possibly obtained by the gluing material in the manner of “riveting” and can also according to the same method be connected to the envelope.

[0015] The device allows, according to this structure different from the prior art, to maintain the overall structure of the voxels in position, which does not exclude the presence of other holding members. Indeed, the envelope consists of acting in a global and external manner to the object which is the single-block structure of voxels.

[0016] Thus, during the stimulation of the active materials present in the voxel structure, the envelope will allow deformation of the device, but will also make it possible to avoid the phenomena of detachment of the voxels while allowing it to return to the initial position after the end of the energy stimuli, thus allowing better reproducibility of the action and thus improving the mechanical strength of the 4D object (and consequently its operating lifetime).

[0017] According to one embodiment, a method of manufacturing the device described according to the first aspect is also presented, the method comprising printing a first envelope section of a first level configured to form a first housing having side walls, integrating a first set of at least one voxel into the first housing of the first envelope section of the first level, printing a second envelope section of a second level configured to form a second housing with at least a portion of the bottom of said second housing corresponding to at least a portion of a face of the first set of at least one voxel of the first level, integrating a second set of at least one voxel into the second housing with at least a portion of the second set of at least one voxel of the second level in contact with the first set of at least one voxel of the first level. BRIEF DESCRIPTION OF THE FIGURES

[0018] The aims, objects, as well as the characteristics and advantages of the invention will emerge better than the detailed description of an embodiment thereof which is illustrated by the following accompanying drawings in which:

[0019] [Fig.l] [Fig.l] represents a view along a section along the plane (x,z) of an embodiment of the device according to the invention.

[0020] [Fig.2] [Fig.2] represents a view along a section along the plane (x,y) of an embodiment of the device according to the invention.

[0021] [Fig.3] [Fig.3] represents a sectional view along the plane (x,z) of a level of the device.

[0022] [Fig.4] [Fig.4] represents a sectional view along the plane (x,z) of a level of the device according to one embodiment.

[0023] [Fig.5A] Figures 5A to 5D represent the method of manufacturing the device according to one embodiment of the invention.

[0024] [Fig.5B]

[0025] [Fig.5C]

[0026] [Fig.5D]

[0027] The drawings are given as examples and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate the understanding of the invention and are not necessarily on the scale of practical applications. In particular, the dimensions are not representative of reality. DETAILED DESCRIPTION

[0028] Before beginning a detailed review of embodiments of the invention, optional features which may possibly be used in combination or alternatively are set out below:

[0029] According to one example, the envelope is elastically deformable in one or more directions in space. The deformation of the envelope is necessary since the voxel structure that surrounds the envelope can change shape following energy stimulation. The envelope can advantageously have elastic deformation allowing a return to the initial state of the device when there is no longer any stimulus. In addition, this makes it possible to avoid accelerated aging of the voxel structure.

[0030] According to one example, the envelope is based on active material. The active material of the envelope makes it possible to have a functional envelope having properties adapted to the environment in which the device will be positioned. For example, it can be imagined that it serves as thermal insulation.

[0031] According to one example, the envelope is made of elastomer, thus making it possible to obtain a homogeneous smooth interface with the external environment.

[0032] According to one example, at least one envelope section has at least one surface discontinuous such as a mesh or a pattern. An envelope section with a discontinuous surface allows for better "breathing" of the device. Thus, after stimulation of the active voxels for a faster return to the initial position, for example, the heat can be evacuated more easily. In addition, an envelope with a mesh surface potentially allows for a more flexible envelope section.

[0033] According to one example, the envelope comprises the stacking along the stacking direction (z) of a first envelope section having a continuous or smooth surface, a second envelope section having a mesh surface, and a third envelope section having a smooth continuous surface. The position of the continuous or discontinuous envelope sections makes it possible to define preferred deformation zones. Here the device will be more rigid at these ends.

[0034] According to an example, the side walls of at least one voxel among, respectively, the first and the second housings are adjusted along the directions (x) and (y) perpendicular to the stacking direction (z) in a sliding manner relative, respectively, to the side faces of the first and second sets of at least one voxel. The sliding adjustment allows ease of integration of the set of voxels into a housing and this without an additional mechanical actuator.

[0035] According to one example, the device comprises a seal interposed between the side walls of the first and second housings and the side faces of the first and second sets of at least one voxel. In order to ensure a connection between the envelope and the voxel structure, a seal may be affixed to form a secured device.

[0036] According to one example, one of the side walls of at least one housing and the side faces of a set of at least one voxel has at least one cavity receiving a portion of the seal.

[0037] According to one example, the side walls of at least one housing and the side faces of a set of at least one voxel have at least one cavity receiving a portion of the seal. The presence of cavities, either on the side walls of the housing of the envelope, or on the set of voxels itself, allows better deformation of a set of elements of the device, by increased cohesion of these elements, while limiting the effects of shearing of the glue. Thus, better longevity over time can be expected. In addition, the seal present in these cavities being preferably a polymerizable resin, it would then advantageously have a dual function of chemical and physical anchoring (rivet effect).

[0038] According to an example, the side walls respectively of the first and second housings are adjusted along the directions (x) and (y) perpendicular to the stacking direction (z) in a tight manner relative, respectively, to the side faces of the first and second sets of at least one voxel. Thus, it is not necessary to use bonding agent such as glue to have a solid device.

[0039] According to an example, wherein the first face of at least one voxel set has a smaller dimension in a direction perpendicular (x) to the stacking direction than the dimension of the second face. In the case where there is a sliding adjustment, this form of voxel set allows better integration of the clearance in the housing. In the case where the adjustment is forced, this allows for an initial facilitated insertion into the housings before forcing.

[0040] According to one example, a step during manufacturing may comprise, after at least one integration step, an application of a seal between the side walls of at least one housing and the side faces of a corresponding set of at least one voxel, the seal preferably being a polymerizable resin. The seal may provide the connection between the envelope section and therefore the envelope with the set of voxels and therefore with the voxel structure.

[0041] According to an example, a step during manufacturing may comprise the integration of at least one of the first and second sets of at least one voxel is carried out in a forced manner using a mechanical tool. Thus an additional mechanical arm may apply a force opposite the stacking direction z.

[0042] It is specified that, in the context of the present invention, the terms “on”, “overcomes”, “covers”, “underlying”, “facing” and their equivalents do not necessarily mean “in contact with”. Thus, for example, the deposition, transfer, bonding, assembly or application of a first element on a second element does not necessarily mean that the two elements are in direct contact with each other, but means that the first element at least partially covers the second element by being either directly in contact with it or by being separated from it by at least one other element. These elements may, for example, be layers.

[0043] A reference frame, preferably orthonormal, comprising the axes X, Y, Z is represented in figures 1 to 3.

[0044] The terms “substantially”, “approximately”, “of the order of” mean “to within 10%, preferably to within 5%”.

[0045] In the following detailed description, use may be made of terms such as "horizontal", "vertical", "longitudinal", "transverse", "top", "bottom", "lower", "upper". These terms must be interpreted relatively in relation to the stacking direction of the levels of the device.

[0046] In the following description, the terms active and passive may be used. By passive, we mean individual elements not sensitive to at least one energy stimulus, preferably insensitive to all types of stimulus of the same nature. By active, we mean individual elements sensitive to at least one stimulus. By sensitivity to at least one energy stimulus, we mean the propensity or aptitude of an individual element, or a material, to modify its spatial and / or functional properties or to have its properties modified under the effect of an energetic stimulus.

[0047] In the following description, the term cavity may be used. A surface having a cavity may be understood as a surface having a hollow portion capable of retaining any type of fluid or object. A cavity may thus be defined as a hollow volume relative to the normal of the surface. This volume is then capable of receiving any type of fluid or object. This volume is preferably a blind volume.

[0048] Multi-material 4D printing allows for the composition of dissimilar objects or structures, at least one of which is active. This offers greater freedom to distribute behaviors in space and time, but also to integrate energetic stimulation into the heart of the object or structure.

[0049] The present invention relates to the multi-material 4D printing of a device 10 allowing the maintenance of a voxel structure 11. The active and / or passive voxels are made of materials allowing the change of shape and / or property of the 4D objects under the action of an energy stimulation which may be external and / or internal. This maintenance is achievable thanks to an envelope 12 at least partly encompassing the structure 11. The device 10 and the method allowing its manufacture by printing will now be described according to several particular examples of embodiment. According to one possibility, the active nature is a capacity for changing dimension or functionality according to an energy stimulus, for example an elongation on electrical command. This active nature is preferably reversible, that is to say that the material returns to an original state after an energy stimulation.According to one example, the active voxels of the structure are of the same nature, or even of the same material. It is appropriate that the active voxels may have different properties and may be associated with several materials. For example, in the case of voxels deformable under energy stimulus, this makes it possible to combine the effect of the deformations, for example to produce a specific consequent deformation of the structure thanks to the individual expansions / contractions of the voxels distributed in the object. It is understood that the deformable active voxels may be advantageously distributed in the structure to produce plural changes of shape; for example, a first stack of active voxels may produce a preferred deformation along a first direction and a second stack of active voxels may produce a preferred deformation along a second direction oblique relative to the first.Other examples of deformation can be twisting or bending. The same can be true for changes in functionality.

[0050] The device according to several embodiments will be described according to figures 1 to 4.

[0051] According to one embodiment, the device 10 comprises several levels 1 to N. N being an integer. The levels 1 to N are preferably stacked in a so-called stacking direction z. The levels 1 to N are advantageously successive and are preferably in contact with each other. Thus, the level N1 is positioned below the level N relative to the stacking axis z.

[0052] According to one embodiment, the device 10 is assembled by level according to the manufacturing method which will be described in the following paragraphs.

[0053] According to one embodiment, each level 1 to N comprises a section 120 of envelope 12. The section 120 of envelope 12 is preferably positioned at the periphery of the device 10. Thus the section 120 of envelope 12 advantageously comprises a surface 1201. The surface 1201 is at least partly in contact with the air or the medium in which the device 10 can be positioned.

[0054] According to one embodiment, the surface 1201 of the section 120 of the envelope 12 may be continuous. This continuous surface 1201 advantageously makes it possible to obtain a level 1 to N which may have greater rigidity.

[0055] According to one embodiment, the surface 1201 of the section 120 of the envelope 12 may be discontinuous. A discontinuous surface 1201 preferably has a surface 1201 in the form of a mesh or a lattice. Generally, it is perforated, in the sense that it comprises at least one opening passing through its entire thickness and exposing a portion of the voxel structure to the outside. A discontinuous surface 1201 advantageously allows the device 10 to cool faster at the end of the thermal energy stimulation so that the device 10 returns to its initial shape more quickly. In contrast to a continuous surface 1201, a discontinuous surface 1201 advantageously allows for less rigidity and thus allows for easier movement of the envelope 10 and the voxel structure 11 during energy stimulation.Such a surface may, in embodiments, provide this elastic return, like a spring.

[0056] According to one embodiment, each level 1 to N of the same device 10 can have an envelope section that is either continuous or discontinuous independently of the envelope section of another level 1 to N of the device 10. For example, as illustrated in [Fig. 1], it is possible to have a continuous envelope section at levels 1 and N (N being the upper level, here in fact level 5) and a discontinuous envelope section at levels 2 to 4. Thus, this configuration makes it possible to have preferred deformation zones with two more rigid ends. In addition, it is possible to produce zones of the envelope with varied performances by layer.

[0057] According to one embodiment, an envelope section comprises at least one housing 1202. Thus each level 1 to N comprises at least one housing 1202. A housing may be defined as a cavity or hollow and is configured to allow at least partial insertion of the voxel structure 11.

[0058] According to one embodiment, each housing 1202 comprises a bottom 1211b of housing 1202. The bottom 1211b of housing 1202 may be at least in part an envelope section 120. The bottom 1211b of housing 1202 may be at least in part the voxel structure 11. The bottom 1211b of housing 1202 extends in a direction perpendicular x to the stacking direction z.

[0059] The bottom 1211b may have a dimension smaller than the upper part of the housing 1202. The upper part of the housing 1202 is understood to be the upper end of the housing 1202. Thus, the housing possibly has a flared section.

[0060] According to one embodiment, each housing 1202 comprises side walls 1211a. The side walls 1211a advantageously extend over a height h along the stacking direction z, preferably parallel to the direction z. The side walls 1211a are advantageously configured to hold the voxel structure 11 at least partially in position. Preferably, in cross-section to the direction z, the side walls 1211a form a closed contour around a set of voxels; thus, the position is maintained by surrounding this set.

[0061] According to one embodiment, each level 1 to N comprises at least one set 110 of at least one voxel 1100. All sets 110 of at least one voxel 1100 of each level 1 to N constitute the voxel structure 11.

[0062] Each voxel 1100 is advantageously printed in 4D by additive manufacturing. Preferably, a set 110 comprises at least one voxel 1100 composed of active material. A set 110 may be composed of voxels from different materials such as hydrogels, shape memory polymers, shape memory alloys, liquid crystal elastomers, flexible polymers or elastomers, conductive materials.

[0063] According to one embodiment, a set 110 may consist of several voxels 1100. In the case where a set 110 of voxels 1100 is composed of several voxels 1100, the voxels 1100 may be assembled together before integration into the device 10. The assembly before integration may be carried out by adhesion, by anchoring or by adjustment. Thus, the voxels 1100 may be connected together by connecting means. A connecting means may be a mechanical, physical and / or chemical connecting means allowing them to undergo significant mechanical deformations. Thus, the voxels may be connected together by a protrusion, a projection, a bead, a hollow, a recess, a housing, a notch or even a notch. Preferably, this assembly is produced / completed by a chemical bonding means, preferably by gluing, and in particular by an advantageously polymerizable resin loaded. The voxels 110 can also be assembled into a set directly in the device 10. According to one option, the housing alone ensures the assembly of the voxels of the set, by the peripheral holding effect explained previously. According to another option, after insertion of each voxel 1100 of a set 110 of a level 1 to N, a joint 13, detailed in the description which follows, can be deposited to participate in the desired cohesion of the voxels.

[0064] According to one embodiment, each set 110 comprises lateral faces 113. The lateral faces 113 of each set 110 of at least one voxel 1100 extend along the stacking direction z. Preferably, the lateral faces 113 are dimensioned to extend over a height equal to the height h of the housings 1202 of section 120 of envelope 12. The lateral faces 113 may extend over a height less than or greater than the height h of the housings 1202 of section 120 of envelope 12. Thus, the housings 1202 of each level 1 to N are advantageously configured to accommodate the sets 110 of at least one voxel 1100 of each level 1 to N.

[0065] According to one example, the side walls 1211a of the housing 1202 are adjusted along a direction x perpendicular to the stacking direction z relative to the side faces 113 of the sets 110 of at least one voxel 1100. Thus, the side faces 113 of the sets 110 are in contact with the side walls 1211a of the housings 1202. In a similar manner, the side faces 113 of the sets 110 of each level 1 to N are in contact with an envelope section 120. Similarly, the side faces 113 of the sets 110 are in contact with the envelope 12.

[0066] According to one example, each set 110 of at least one voxel 1100 comprises a first face 114 and a second face 115 opposite each other connected to each other by the lateral faces 113. The first face 114 and second face 115 extend in a direction x perpendicular to the stacking direction z. Thus, the first face 114 and second face 115 preferably extend parallel to the bottom 1211b of the housing 1202.

[0067] According to one example, the first face 114 of each set 110 may be in contact with the bottom 1211b of the housing 1202. The contact may be direct or be made via an adhesive interface. Thus, for each level 1 to N, each set 110 may be integrated into a housing 1202 of a section 120 of the casing 12.

[0068] According to an example, the first face 114 of each set 110 may have a dimension 114d along the x axis of dimension equal to the bottom 1211b of housing 1202. Preferably, the second face 115 of each set 110 may have a dimension equal to the dimension 114d of the first face 114. Thus, the sets 110 are preferably composed of voxels 110 having a parallelepiped shape, advantageously rectangular, and preferably cubic. The dimensions of the set 110 may thus be equal to the dimensions of the housing 1202 of a section 120 of envelope 12; the assembly of a set 110 is then preferably carried out by forcing, thus allowing an assembly preferably without a bonding interface.

[0069] According to one example, the first face 114 of each set 110 of a level 1 to N may be at least partly in contact with the envelope 12.

[0070] According to one example, the first face 114 of each set 110 of a level 2 to N is at least partly in contact with a set 110 of a level N1.

[0071] According to an example, illustrated in [Fig. 3], the dimension 114d of the first face 114 of each set 110 may have a dimension 114d along the x axis smaller than the bottom dimension 1211b of the housing 1202. Similarly, the dimension 114d of the first face 114 may be smaller than the dimension of the second face 115. Thus, the insertion of each set 110 into a housing 1202 is facilitated. Indeed, preferably the dimensions of the set 110 are smaller than the dimensions of the housing 1202, thus allowing insertion of the set 110 into the housing 1202 by sliding without the need for an additional mechanical actuator. However, in order to guarantee a connection between the clearance 110 and the housing 1202 of a section 120 of the casing 12, a seal 13 illustrated in [Fig.2] and 3 can be inserted to fill any gaps that may be present and thus secure the device 10.Thus a joint 13 may be present between the side walls 121 1a and the side faces 113. Alternatively or in addition, the joint 13 may form an interface between the voxels 1100 of the set 110.

[0072] According to an example illustrated in [Fig.4], similarly to the example illustrated in [Fig.3], the dimensions of the clearance 110 may be smaller than the dimensions of the housing 1202, thus allowing the clearance 110 to be inserted into the housing 1202 by sliding without the need for an additional mechanical actuator. However, in order to guarantee an additional connection between the clearance 110 and the housing 1202, the side walls 1211a of the housing 1202 and / or the side faces 113 of the clearance 110 may comprise at least one cavity 131. Preferably, the side walls 1211a of the housing 1202 and / or the side faces 113 of the clearance 110 may comprise several cavities 131. The cavities 131 advantageously make it possible to accommodate the material of the inserted seal 13 in order to fill any gaps that may be present and thus secure the device 10 as best as possible.According to one example, a cavity 131 is present respectively on the side walls 121 of the housing 1202 and the side faces 113 of the set 110, the cavities 131 are thus preferably at least partly opposite each other. Preferably the cavities 131 are completely opposite each other. The two preceding configurations are shown in [Fig.4]. The cavities 131 can thus advantageously have an arrangement and a shape so as to have a chemical and physical anchoring function, the dimensions shown of the cavities 131 in [Fig.4] are indicative and may be different. Thus, upon activation of the active voxels 1100 and deformation of the envelope 12, the polymerizable resin, or glue, present in the seal 13, can undergo lower shear than without the presence of the cavities 131. This thus allows for better deformation and increased longevity of the device. Alternatively or in addition, the cavities 131 may be formed at an interface between the voxels 1100 of the set 110 and have the same characteristics and advantages as described for the cavities 131 present at the interface between the envelope section 120 of a housing 120 and a set 110 of voxels 1100.

[0073] According to one example, the second face 115 of each set 110 of a level 1 to N may be at least partly in contact with the envelope 12.

[0074] According to one example, the second face 115 of each set 110 of a level 1 to N1 may be at least partly in contact with a set 110 of a level N.

[0075] Description of a device with at least two levels:

[0076] The device 10 will now be described as being a device 10 comprising at least two levels 1 and 2.

[0077] According to one embodiment, a first level 1 comprises a first section 121 of envelope 12. The first section 121 of envelope 12 comprises a first housing 1211 configured to accommodate a first set 111 of at least one voxel 1100.

[0078] According to one embodiment, a second level 2 is superimposed on the first level 1 along the stacking axis z. The second level 2 comprises a second section 122 of envelope 12. The second section 122 of envelope 12 comprises a second housing 1222 configured to accommodate a second set 112 of at least one voxel 1100.

[0079] According to one embodiment, at least a portion of the first set 111 of at least one voxel 1100 of the first level 1 is in contact with at least a portion of the second set 112 of at least one voxel 1100 of the second level 2. Similarly, at least one voxel 1100 of a level N1 is in contact with at least one voxel 1100 of a level N. Preferably, at least one voxel 1100 of a level which is in contact with one or more voxels of another level is a voxel 1100 composed of active material. Thus, during an energy stimulation, the entire device 10 can be activated on each of the levels 1 to N. There is therefore in this case a continuity of the distribution of active and passive voxels along the stack forming the voxel structure.

[0080] Similarly, at least a portion of the second face 115 of the first set 111 is in contact with at least a portion of the first face 114 of the second set 112. As a result, the bottom 1211b of the second housing 1222 is at least partly the second face 115 of the first set 111. Thus each set 110 is at least partially in contact so as to form a single-piece assembly of the voxel structure 11.

[0081] According to one embodiment, after assembly of each of the levels 1 to N, all of the sets 110 of voxels 1100 form a single-piece voxel structure 11 surrounded by an envelope 12, thus allowing the voxels to be held in position.

[0082] According to one embodiment, the envelope 12 can thus deform under the action of the active voxels 1100. The deformation of the envelope 12 can be elastic, thus allowing a return to the initial state of the device 10. The elastic deformation of the envelope 12 allows reproducibility of the deformation and thus avoids accelerated aging of the voxel structure 11. The envelope 12 can be made from an elastomer or from a two-component silicone, preferably making it possible to obtain a smooth interface with the external environment. In addition, the envelope 12 can be based on a functional material and, for example, thus allow the envelope to serve as a thermal insulator or even a biocompatible interface. Additionally, the envelope 12 can be removed while retaining the voxel structure 11; the structure 11 can thus, for example, be disassembled and the voxels reused.The envelope may itself comprise one or more portions of active material, or even be entirely made of such a material. For example, its deformation may be controlled under stimulus to accompany that of the structure and therefore improve actuation performance.

[0083] The method of manufacturing the device

[0084] The method of manufacturing the device 10 will now be described in the pa following graphs. The process is illustrated in Figures 5A to 5D. The process steps may not be successive and may have a different order.

[0085] According to one embodiment, a first level 1 is created by 3D printing, possibly by direct ink writing (which can be translated as ink writing), or by fused filament fabrication (which can be translated as fabrication by fused filament) via a print head 15 of a first section 121 of envelope 12 comprising a first housing 1211.

[0086] According to one embodiment, the first set 111 assembled beforehand, preferably by adhesion, of at least one voxel 1100 can be inserted robotically, preferably by an articulated arm or a suction cup 16 mounted on an assembly station in the first housing 1211.

[0087] According to one embodiment, depending on the dimensioning of the first set 111 relative to the first housing 1211, the first set 111 of voxels will be assembled by sliding and subsequently a joint casting step 13 may be added after the step of inserting the first set 111 into the first housing 1211.

[0088] According to one embodiment, depending on the dimensioning of the first set 111 relative to the first housing 1211, the first set will be assembled by forcing; thus a step of compression by a mechanical arm of the first set 111 in the first housing 1211 may be added after the step of initiating insertion of the first set 111 into the first housing 1211, or during this insertion.

[0089] According to one embodiment, a second level 2 is created by printing according to a method described previously a second section 122 of envelope 12 comprising a second housing 1222.

[0090] Similarly to the first level, the second set 112 can be inserted into the second housing 1222. The second set 112 is preferably at least partly in contact with the first set 111. The first face 114 of the second set 112 at least partly surmounts the second face 115 of the first set 111. This second face 115 can be formed by a coating placed on the set after insertion such as a bonding interface.

[0091] These steps take place successively until the desired device 10 is obtained. To do this, a program can be implemented to manage the printing and insertion of the sets 110 at each level 1 to N.

[0092] The invention is not limited to the embodiments previously described and extends to all embodiments covered by the invention.

[0093] DIGITAL REFERENCES 1: First level 2: Second level 3: Third level 4: Fourth level N: Level N h: Height of the side walls of the housing 10: Device 11: Voxel structure 110: Set of at least one voxel 111: First set of at least one voxel 112: Second set of at least one voxel 113: Game side faces of at least one voxel 114: First game face of at least one voxel 114d: First game face dimension of at least one voxel 115: Second game face of at least one voxel 115d: Second game face dimension of at least one voxel 1100: One voxel 12: Envelope 120: Envelope section 1201: Envelope section area 1202: Envelope section housing 121: First envelope section 1211: First accommodation 122: Second envelope section 1222: Second accommodation 1211a: Housing side walls 1211b: Housing fund 13: Joint 131: Cavity 14: Printing plate 15: Print head 16: Arm / suction cup

Claims

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2.

3. Claims Device (10) comprising a voxel structure (11) having at least one voxel (1100) based on an active material being configured so that said voxel (1100) activates under external or internal energy stimulation, characterized in that it comprises an envelope (12) encompassing at least a part of the structure (11), the envelope (12) and the structure (11) forming, stacked in a so-called stacking direction (z), at least a first (1) and a second (2) level comprising: • respectively a first section (121) of envelope (12) and a second section (122) of envelope (12) respectively comprising a first housing (1211) and a second housing (1222) each comprising side walls (1211a) extending over a height (h) in the stacking direction (z), • respectively a first set (111) of at least one voxel (1100) and a second set (112) of at least one voxel (1100), each comprising lateral faces (113) extending in the stacking direction (z), the lateral faces (113) joining a first face (114) and a second face (115) opposite in the stacking direction (z), the first housing (1211) receiving the first set (111) of at least one voxel (1100), the second housing (1222) receiving the second set (112) of at least one voxel (1100), the side walls (1211a) of the first (1211) and second (1222) housing being configured to hold in position respectively the side faces (113) of the first (111) and second (112) sets of at least one voxel (1100), the levels (1, 2) being stacked so that the second face (115a) of the first set (111) of at least one voxel (1100) and the first face (114) of the second set (112) of at least one voxel (1100) are at least partially in contact so as to form a single-piece assembly of the structure (11). Device (10) according to the preceding claim, in which the envelope (12) is elastically deformable. Device (10) according to any one of the preceding claims, in which the envelope (12) is based on active material.

4. Device (10) according to any one of the preceding claims, in which the casing (12) is made of elastomer.

5. Device (10) according to any one of the preceding claims, wherein at least one envelope section (120) has at least one discontinuous surface (1201) such as a mesh or a pattern.

6. Device (10) according to any one of the preceding claims, wherein the envelope (12) comprises the stacking in the stacking direction (z) of a first section (121) of envelope (12) having a continuous or smooth surface (1201), of a second section (122) of envelope (12) having a mesh surface (1201), and of a third section of envelope (12) having a smooth continuous surface (1201).

7. Device (10) according to any one of the preceding claims, wherein the side walls (1211a) of at least one of, respectively, the first (1211) and the second (1222) housing are adjusted in a direction (x) perpendicular to the stacking direction (z) in a sliding manner relative to, respectively, the side faces (113) of the first (111) and second (112) sets of at least one voxel (1100).

8. Device (10) according to the preceding claim, in which the device (10) comprises a seal (13) interposed between the side walls (1211a) of the first (1211) and second (1222) housings and the side faces (113) of the first (111) and second (112) sets of at least one voxel (1100).

9. Device (10) according to the preceding claim, in which at least one of the side walls (1211a) of at least one housing (1202) and the side faces (113) of a set (110) of at least one voxel (1100) has at least one cavity (131) receiving a part of the seal (13).

10. Device (10), according to the preceding claim, in which the side walls (1211a) of at least one housing (1202) and the side faces (113) of a set (110) of at least one voxel (1100) have at least one cavity (131) receiving a part of the seal (13).

11. Device (10) according to any one of claims 1 to 6, wherein the side walls (1211a) respectively of the first (1211) and of the second (1222) housings are adjusted in a direction (x) perpendicular to the stacking direction (z) in a tight manner relative, respectively, to the side faces (113) of the first (111) and second (112) sets of at least one voxel (1100).

12. Device (10) according to any one of the preceding claims, in which the first face (114) of at least one set (110) of voxels (1100) has a dimension (114d) which is smaller in a direction perpendicular (x) to the stacking direction than a dimension (115d) of the second face (115).

13. A method of manufacturing the device (10) according to any one of the preceding claims comprising: - printing a first section (121) of envelope (12) of a first level (1) configured so as to form a first housing (1211) having side walls (1211a), - integrating a first set (111) of at least one voxel (1100) into the first housing (1211) of the first section (121) of envelope (12) of the first level (1), - printing a second section (122) of envelope (12) of a second level (2) configured so as to form a second housing (1222) with at least a portion of the bottom (1211b) of said second housing (1222) corresponding to at least a portion of a second face (115) of the first set (111) of at least one voxel (1100) of the first level (1),- integrating a second set (112) of at least one voxel (1100) into the second housing (1222) with at least a portion of the second set (112) of at least one voxel (1100) of the second level (2) in contact with the first set (111) of at least one voxel (1100) of the first level (1).,

14. Method of manufacturing the device (10) according to the preceding claim, comprising, after at least one integration step, an application of a seal (13) between the side walls (1211a) of at least one housing (1202) and the side faces (113) of a corresponding set (110) of at least one voxel (1100), the seal (13) preferably being a polymerizable resin.

15. A method of manufacturing the device (10) according to claim 13, wherein the integration of at least one of the first (111) and the second (112) set of at least one voxel (1100) is carried out in a forced manner using a mechanical tool.

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