Related application

[0001. The present application claims priority to the earlier European application N° 21154434.1 filed on January 29, 2021 in the name of ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE (EPFL) et al., the content of this earlier application being incorporated in its entirety by reference in the present application.

Technical Field

[0002. The invention is in the field of devices for construction and in particular to a removable clip connection device particularly adapted to bamboo structures.

Background Art

[0003. In 2017, the building sector was responsible for 39% of energy-related carbon dioxide (CO2) emissions, from which 11 % are directly related to the construction industry.

[0004. After several decades of quasi-monopoly of steel and concrete structures in European countries, designers are getting aware of the negative environmental consequences of these choices, looking for solutions which could reduce the impact of designs on the environment without altering their quality, and wood is being reconsidered, as it is a more sustainable structural material. In fact, in its cycle, wood grows absorbing the carbon in the CO2 of the atmosphere and releases it in the atmosphere during its degradation. The use of wood in buildings -as any other natural material- could thus be seen as a storage of the carbon it contains, at the condition that the production of wood is conducted on a sustainable way, cutting no more wood in a forest than can grow. This condition may be difficult to respect if the use of wood as a building material continues to increase, especially in the Western part of the world, where only a small surface of forest is left. [0005. Bamboo offers better mechanical properties than wood (e.g. better strength than almost all softwoods and comparable to hardwoods) and a natural circular hollow section fitted for structural use. Moreover, it can be harvested on average after 3-5 years compared to 20-40 for timber. This means that, on the same land surface, a larger quantity of bamboo than wood could be produced per year: 78.3 ton/(ha*year) for the bamboo compared to 17.5 ton/(ha*year) for timber. The possibility to use bamboo without transformation is one of the main reasons why bamboo is a more sustainable material than steel, concrete and wood. The energy needed if the bamboo is used in its natural form is then only that needed for the harvesting, preservation process and transportation. Therefore, if the bamboo is produced locally and in a durable way, it is a very sustainable solution.

[0006. The use of raw bamboo as a structural element could thus help to decrease the ecological footprint of buildings, as well as other kind of buildable structures. Bamboo culms have a circular hollow section which is structurally efficient, because the mass is disposed at the exterior of the section, increasing the moment of inertia of the section, and therefore increasing the bending resistance of the culm.

[0007. Traditional bamboo buildings usually use leashed connections. This technique, although avoiding making holes in the bamboo, and therefore decreasing the risk of failure, leads to a non-stiff connection. Today, several new types of connections have been developed, in order to improve the structural properties of the connection, its durability and its aesthetic. They are usually made with steel (prone to corrosion) or wood. At the same time, the various connections used in raw bamboo constructions present several drawbacks, including one or more between non-standardisation, difficulty to assemble, not high enough reliability, impossibility to remove them, complicated manufacture and so forth.

[0008. Generally speaking, the use of raw bamboo as a structural element outside the Asian continent, Africa and Latin America (where it originates) induces several complexities, including lack of skilled workers, the lack of knowledge about this material and particularly, in view of the above limitations, the lack of a user-friendly and robust connection system to ease the mounting/demounting of bamboo-based structures.

[0009. Publication US 2018/0015606 discloses a modular pole for use with a pool device comprising: first tube having a first end and a second end, the second end defining a first through-hole oriented perpendicular to an axis of the first tube; a second tube having a first end and a second end, the first end defining a second through-hole oriented perpendicular to an axis of the second tube, and the second end including a device connector for connecting the second tube to the pool device; and a first tube connector configured to be positioned within the first tube and the second tube and having a first retractable protrusion configured to extend through the first through-hole when the first tube connector is positioned within the first tube and a second retractable protrusion configured to extend through the second through-hole when the first tube connector is positioned within the second tube.

Summary of invention

[0010. In order to address and overcome at least some of the above-mentioned drawbacks of the prior art solutions, the present inventors developed a connection device particularly adapted for raw bamboo constructions, having improved features and capabilities. Of course, the present invention is not limited to applications in the field of bamboo constructions and its principle may be applied in other type of constructions, using other materials than bamboo.

[0011. The purpose of the present invention is therefore that of providing a connection device that overcomes or at least reduces the abovesummarized limitations affecting known solutions according to the prior art. [0012. In particular, a first purpose of the present invention is that of providing a compliant clipping mechanism easy to assemble and disassemble, adapted to light, temporary structures as well as more solid ones.

[0013. A further purpose of the present invention is that of providing a connection system possibly made with sustainable materials and with a sustainable production process. [0014. Still a further purpose of the present invention is that of providing a connection system adapted to the irregularities of bamboo culms and their mechanics, which is standardisable, strong and reliable, easy to manufacture and low cost, as well as able to take up loads in compression or tension, shear or bending moment.

[0015. All those aims and other have been accomplished with the present invention, as described herein and in the appended claims.

[0016. In view of the above-summarized drawbacks and/or problems affecting the current solutions, in a first aspect of the present invention there is provided a clip connector device according to claim 1.

[0017. In particular, in some embodiments, a clip connection device according to the present disclosure comprises:

[0018. a) a base located at a first end of the device, said base having a first surface and an opposed second surface;

[0019. b) at least a pair of face-to-face branches, each branch stemming from the first surface of said base; and

[0020. c) a blocking button located at the extremity of each branch, defining an opposed second end of the device

[0021 . wherein each branch is directed outwardly with respect to the centre of the base so to be elastically pre-bent or pre-tensioned. For instance, each branch can be pre-bent or pre-curved so to be elastically tensioned.

[0022. Another aspect of the present invention relates to an assembly comprising a clip connector device according to the present disclosure and a structural element. The structural element may be a tubular element, such as, but not limited thereto, a bamboo culm, comprising at least a pair of opposed bores configured to mate with the blocking buttons of the clip connector device. Additionally or alternatively, the said structural element may be one comprising a plurality of recesses configured to mate with a plurality of posts located on a surface of the base of the clip connector device.

[0023. Still another aspect of the present invention relates to the use of a clip connector device or of an assembly according to the invention for the manufacture of an article of manufacture, such as demountable bikes, bamboo bikes, scaffoldings, fences, games for children, bamboo tents, trusses for construction structures, shadow devices, verandas and/or furniture, as non-limiting examples.

[0024. Still a further aspect of the present inventions relates to a kit comprising a clip connector device according to the invention and a connection element formed for example from a threaded node, a toothed node and a screw configured to reduce unclipping risks of the clip device. Other equivalents means are of course possible in the frame of the present invention.

[0025. Further embodiments of the present invention are defined by the appended claims.

[0026. The above and other objects, embodiments, features and advantages of the herein presented subject-matter will become more apparent from a study of the following description with reference to the attached figures showing some preferred aspects of said subject-matter.

[0027. In embodiments, the invention concerns a clip connector device comprising: a) a base located at a first end of the device, said base having a first surface and a second surface; b) at least a pair of face-to-face branches, each branch in a pair stemming from the first surface of said base; and c) a blocking button located at the extremity of each branch, defining an opposed second end of the device and wherein each branch in a pair is directed outwardly one with respect to the other so to be elastically pre-tensioned.

[0028. In embodiments, the blocking buttons are preferably devoid of any tapered surface. Still more preferably, the blocking buttons are designed to have an outward-directed surface that do not overstep the external surface of the tubular element it is connected to. This is preferably realized by implementing said outward-directed surface as a blunt surface.

[0029. In embodiments, at least one blocking button may comprise an anti-de- plugging element.

[0030. In embodiments, the connector device may comprise a pin spanning from the first surface of the base through the second surface of the base.

[0031 . In embodiments, the clip connector device may comprise at least a second pair of face-to-face branches, each branch in said additional pair stemming from the second surface of the base. [0032. In embodiments, the clip connector device may comprise a further pair of face-to-face branches, each branch stemming from a lateral portion of the base.

[0033. In embodiments, the clip connector device has a base comprising connection means. Connection means are substantially adapted and configured to connect at least one of 1) two or more clip connectors between them and 2) a clip connector with a structural element. For example, a clip connector device may comprise a basis having a plurality of posts defining a toothed pattern on a surface of said base, or a threaded member or pattern, such as a screw-like element or a nut-like element.

[0034. In embodiments, the clip connector may comprise a further pair of face-to- face branches stemming from a further base comprising further posts, the base and the further branches being connected together via an assembly of said posts with said further posts.

[0035. In embodiments, the invention concerns an assembly comprising a clip connector device as defined herein and a structural element.

[0036. In embodiments, the structural element may comprise a plurality of recesses configured to mate with a plurality of posts of the clip connector device.

[0037. In embodiments, the structural element may comprise a threaded member or pattern configured to mate with a threaded member or pattern, such as a screw-like element or a nut-like element, of the clip connector device.

[0038. In embodiments, the structural element is a tubular element comprising at least a pair of opposed bores configured to mate with the blocking buttons of the clip connector device. In the preferred embodiments, the blocking buttons are designed to have an outward-directed surface that do not overstep the external surface of the tubular element it is connected to, so that the bores are filled with the blocking buttons while creating a blunt surface on the tubular element.

[0039. In embodiments, the invention concerns the use of a clip connector device or of an assembly as defined herein for the manufacture of an article.

[0040. In embodiments, the article comprises one of demountable bikes, bamboo bikes, scaffoldings, fences, games for children, bamboo tents, trusses for construction structures, shadow devices, verandas and furniture. Brief description of drawings

[0041 . Fig. 1 schematically depicts an isometric view of the connection clip device according to one embodiment of the invention;

[0042. Fig. 2 schematically depicts a longitudinal cross-section view of the connection clip device according to the embodiment depicted in Fig. 1 , wherein the device further comprises a base having a toothed pattern for mechanical connection to a structural element;

[0043. Fig. 3 schematically depicts an isometric view of the connection clip device according to the embodiment depicted in Fig. 2, further comprising an anti- de-plugging element traversing the top blocking buttons via thru holes or bores;

[0044. Fig. 4 schematically depicts a longitudinal cross-section view of the connection clip device according to the embodiment depicted in Fig. 3 inserted into a structural element, in the depicted case a bamboo culm, into an assembly;

[0045. Fig. 5 schematically depicts an isometric view of the connection clip device according to another embodiment of the invention, the clip having two pairs of face-to-face branches stemming from one base;

[0046. Fig. 6 schematically depicts an isometric view of the connection clip device having two pairs of face-to-face branches according to the embodiment depicted in Fig. 5, the device being connected as an assembly to a first structural element with a first pair of face-to-face branches and about to be connected with a second structural element through a second pair of face- to-face branches, in the depicted case both structural elements being bamboo culms;

[0047. Fig. 7 schematically depicts a lateral view of the connection clip device according to another embodiment of the invention, the device being a so- called “2D node” having four pairs of face-to-face branches made of clip devices and stemming from different surfaces of a single base;

[0048. Fig. 8 schematically depicts an isometric view of the connection clip device according to another embodiment of the invention, the device being a so- called “3D node” in which five devices are interconnected between them through a structural node element into an assembly, three of those devices being inserted into bamboo culms to form assemblies;

[0049. Fig. 9 depicts two isometric views of the connection clip device according to another embodiment of the invention, wherein the base of the clip is designed to comprise a threaded member or pattern. In the embodiment shown on the right, the base of the clip is configured as a nut-like element that mates with a threaded member or pattern of a screw-like structural element;

[0050. Fig. 10 depicts an isometric view of the connection clip device according to a similar embodiment of the invention as depicted in Fig. 9, wherein the base of the clip is designed to comprise a threaded member or pattern. In the shown embodiment, the base of the clip is configured as a screw-like element to mate with a threaded member or pattern of a nut-like structural element;

[0051 . Figs. 11 to 13 schematically depict three longitudinal cross-section views of the connection clip devices according to the embodiments depicted in Figs. 9 and 10 inserted into a structural element, in the depicted case a bamboo culm, into an assembly. The clips are in turn also connected on the opposed end, via their threaded bases, to a second structural element such as a platform or other structural supports via a nut-like or a screw-like element;

[0052. Fig. 14 depicts an isometric view of an assembly comprising a threaded, nut-like, three-branched structural node to which three clips having a screwlike element at their bases are connected. A further elongated, tube-like structural member is connected to one of the clips via the clip branches, with the blocking buttons inserted into the tube’s bores;

[0053. Fig. 15 depicts an isometric view of a connection clip device having two pairs of face-to-face branches, wherein said connection clip is composed of a first two-branches clip having a base comprising a nut-like element and a second two-branches clip having a base comprising a screw-like element. For the ease of understanding, the two-branches clips are depicted as not connected.

Detailed description of the invention [0054. The subject-matter described in the following will be clarified by means of a description of those aspects and embodiments which are depicted in the drawings in an illustrative and non-limiting manner. It is indeed to be understood that the scope of protection of the invention is not limited to those aspects described in the following and depicted in the drawings. Moreover, it is to be understood that the specific conditions or parameters described and/or shown in the following are not limiting of the scope of protection of the invention, and that the terminology used herein is for the purpose of describing particular aspects by way of example only and is not intended to be limiting either.

[0055. Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, unless otherwise required by the context, singular terms shall include pluralities and plural terms shall include the singular. The methods and techniques of the present disclosure are generally performed according to conventional methods well known in the art and as described in various general and more specific references that are cited and discussed throughout the present specification unless otherwise indicated.

[0056. Non-limiting aspects of the subject-matter of the present disclosure will be described by way of embodiments and examples with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale. For purposes of clarity, not every component is labelled in every figure, nor is every component of each aspect of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention.

[0057. As used in the following and in the appended claims, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Also, the use of "or" means "and/or" unless stated otherwise. Similarly, "comprise", "comprises", "comprising", "include", "includes" and "including" are interchangeable and not intended to be limiting. It is to be further understood that where for the description of various embodiments use is made of the term "comprising", those skilled in the art will understand that in some specific instances, an embodiment can be alternatively described using language "consisting essentially of" or "consisting of."

[0058. The design of the clip device of the invention has been conceived and implemented to overcome the previously described limitations of the prior art regarding connection systems, particularly for bamboo constructions - without limitation to such constructions -. The inventors created, based on the establishment of mathematical models and prototyping for defining the dimensional parameters and to predict the failure mode of the system, a connection device in the form of a clip especially adapted to the irregularities of bamboo culms and their mechanics, standardisable, easy to manufacture, low cost and able to take up loads in compression, tension, shear or bending moment. The following description will mainly refer to constructions using bamboo culm as a non-limiting example, the principles of the present invention being applicable to other construction approaches using tubes similar to bamboo culm as mentioned above.

[0059. With reference to Fig. 1 , a first embodiment of a clip connector device according to the invention is shown. The device features a base 100 located at a first end 10 of the device, said base 100 having a first surface 101 and a second surface 102; at least a pair of face-to-face branches 201 and 202, each branch of a pair stemming from the first surface 101 of said base 100; and a blocking button 301 and 302 located at the extremity of each branch 201 and 202, defining a second end 20 of the device, wherein each branch

201 and 202 in a pair is directed outwardly one with respect to the other so to be elastically pre-tensioned. For example, in Fig. 1 , branches 201 and

202 are slightly bent/curved to this effect.

[0060. The design of the clip of the invention is also based, at least in part and in some embodiments, on considerations depending on the very nature of bamboo culms: a relatively flexible structure, with a tubular cross-section, and easy to be drilled to provide thru holes or bores spanning the entire thickness of the bamboo culm. As a way of example, due to the internal structure of a bamboo culm and its mechanical properties, de-plugging of a connection device can be experienced (probably due to the fact that the stiffness of the connection could not be constant -proportional to the stress- ). In order to increase the rigidity of the system against de-plugging, the branches 201 and 202 of the connection clip are modelled to induce a prestress bending or curvature at rest state, which renders the pre-stressed branches more resistant against de-plugging and grants some tolerance in view of the interior diameter of the bamboo culm (which can be for instance about 0.1 times larger than the distance between the two exterior extremities of the branches, for instance about 2 or 3 mm).

[0061. This is further shown in Fig. 2, where a pair of face-to-face branches 201 and 202 stemming from a first surface 101 of a base 100 are directed outwardly one with respect to the other so to be elastically pre-tensioned. One advantage of this design and configuration relies, among others, in the possibility to adapt the clip to many different culms/tubular structures, relatively independent on their diameter. The pre-tensioning of the branch pairs and their relative direction allows for a “universal” design that, contrary to many examples provided in the art, can fit into different mating construction structures, as long as the diameter of these latter do not exceed the bending angle of the branch pair (see the definition of “bending angle <|>" provided herein below).

[0062. As used herein, the wording “directed outwardly one with respect to the other”, when referring to the branches 201 and 202, is intended as the configuration of a pair of opposing, face-to-face, beam-like branches that experience a divergence of their respective distal portions (comprising blocking buttons 301 and 302), vis-a-vis their proximal base portion, away from an imaginary central axis y located between the branches 201 and 202. This can be easily visualized with reference to a symmetry axis y passing through the base 100 and parallel to a plane longitudinally cutting the device (Fig. 2). At rest state, an axis y‘ running along the length of a branch 201 , 202 intercepts the axis y so to define a bending angle <|>, due to the bending or curvature of the branch, or to the relative position of the branches 201 , 202. The bending angle <|) will depend on several factors, including the manufacturing material used for the clip, the thickness and the section of the bamboo culm (or other structural element), the size of the buttons 301 , 302 and the like, and it is typically comprised between 3 and 20°, such as between 3 and 10°, for instance 6°. These are only examples and other values are possible depending on circumstances, applications and embodiment. As for the branches 201 , 202, these have typically a length which is chosen to be between 2 and 3 times the exterior diameter of the structural element (e.g. a bamboo culm) to be connected with, usually comprised between 5 and 20 cm and a beam-like shape to better accommodate the tubular structure inside the bamboo culm or other structural element. Also in this case, the used material for the clip manufacturing and/or the shape/size of the bamboo culm have an influence on size and/or shape of the branches. Again, these are non-limiting examples and other values may be envisaged depending on the applications and materials used (see the applications listed above).

[0063. For instance, when the connection is plugged-in in a culm 1000, the top of the branches 201 , 202 must be bent to be able to pass through the inner tubular section of the culm. The minimum distance of displacement of the top of the branches 201 , 202 is equal to the sum of the thickness of the bamboo culm and the distance due to the pre-stress curvature. The induced tension in the branches should not be too large to avoid failure of the clip. Accordingly, branches 201 , 202 are typically designed and manufactured to preferably have a flexural rigidity comprised between 1 and 10 GPa m ⁴ , such as between 2 and 6 GPa m ⁴ . Other values are of course possible depending on the circumstances or applications. The expression “flexural rigidity” refers to the force couple required to bend a non-rigid structure in one unit of curvature or it can be defined as the resistance offered by a structure while undergoing bending. In a beam or rod, flexural rigidity (defined as El) follows the local deflection equation for beams in curvilinear coordinates, also known as the equation of Euler-Bernoulli:

[0064. I/ ? = M/El

[0065. where the curvature is /p = d6/ds. The relationship between bending moment and beam deformation therefore reads as

[0067. Which in Cartesian coordinates for large deflections and an initially horizontal beam can be written as

[0068. where E is the Young's modulus (in Pa), I is the second moment of area (in m ⁴ ), y is the transverse displacement of the beam at x, and M(x) is the force couple at x. Flexural rigidity has SI units of Pa m ⁴ (which also equals N m ² ). [0069. The loads are transferred from the bamboo culm 1000 to the branches 201 , 202 mostly through the buttons 301 , 302. These buttons are in some embodiments circular, and are adapted to fit into bores 1100 (see figures 4, 6, 11-13) present on the walls (and spanning therethrough) of a tubular element/culm 1000, so to avoid stress concentrations both in the connection and in the bamboo culm 1000 (in which the bores 1100 will indeed also be circular). Importantly, in the most preferred embodiments, the blocking buttons 301 , 302 are devoid of any tapered surface. Blunt edge surfaces of the blocking buttons 301 , 302 allow a more stable and robust connection with a bamboo culm 1000, while at the same time guaranteeing a more uniform forces distribution. The size and the shape of the blocking buttons 301 , 302, as well of any other element and component of the connection clip according to the invention, may be chosen depending on the needs and circumstances, without departing from the general inventive concept defining the invention. However, in the most preferred embodiments, the blocking buttons 301 , 302 are designed to have an outward-directed surface that do not overstep the external surface of a tubular element 1000 it is connected to, so that the bores 1100 of said tubular element are filled with the blocking buttons 301 , 302 while creating a blunt surface on the tubular element 1000 (see for instance Figs. 4 and 6, where a blunt surface is created and the interface between the blocking buttons and a culm surface). This aspect is advantageous for avoiding that a surface of the buttons 301 , 302 extends beyond the external surface of a tubular element 1000 and that an accidental de-plugging of a clip/culm assembly may take place. Additionally, in this configuration, the final assembly is more appealing and good-looking, especially if the outward-directed surface of the buttons have matching colours compared to the culm colour, so to impart a uniform appearance to the final clip/culm assembly. On the contrary, it is also possible to use different colours to clearly show the position of the buttons (and help disassembly for example).

[0070. Regarding the materials for the manufacture of the connection clip device, the choice is not limiting as long as the used materials are rigid enough to withstand stress and compression/tension loads of the desired constructions, and sufficiently elastic for the branches to be bent against the pre-tensioning to be inserted into a bamboo culm (or a tube made of another material), while regaining their shape and positioning once in place into the culm. Suitable “connection clip materials” can be selected for instance from a non-limiting list comprising wood, various thermoplastics and thermosets having a Young’s modulus typically comprised between 2 and 12 GPa, including for instance PET, PLA and ABS. Other portions of the device, e.g. all or part of the base and/or the buttons, may be produced with more rigid, strong and/or though materials including for instance metals or polymeric materials having a Young’s modulus higher than 12 GPa, depending on the needs and circumstances, such as fiber-reinforced PLA polymers.

[0071 . Interestingly, the branches 201 , 202 will not only be submitted to tension. In fact, there is a bending moment which will appear in the branches, because of the eccentricity of the application of the tension load from the culm to each branch. The main consequence of that bending is that, if the displacement of the buttons 301 , 302 at the top of the connection is too large, it may cause de-plugging-in of the connection, and therefore failure of the system. As it has been demonstrated with real world, implemented prototypes, de-plugging-in of the connection would generally be the most probable mode of failure. Accordingly, besides optimizing the various parameters of the connection clip, in embodiments of the invention the connector device further features, on at least one blocking button 301 , 302, an anti-de-plugging element 600 (see Figs. 3 and 4) could be added to prevent the branches to bend towards the interior of the culm in case of tension loading. The anti-de-plugging element 600 can be embodied as an elongated element, such e.g. a steel screw, configured to pass through ad hoc bores 303, 304 crafted in the blocking buttons 301 , 302. The anti-de- plugging element 600 can be added once the connection is plugged in the culm or structural element 1000, by passing it through a top button (e.g. 301) of one branch, then turn it to fix its position (Fig. 4). In another embodiment, the shape of the buttons may be formed to reduce the deplugging risk.

[0072. In one embodiment, the clip connector device according to the invention further comprises a pin 400 spanning from the first surface 101 of the base 100 through the second surface 102 of the base 100 to avoid sliding of the connection device once in place into a bamboo culm or structural element 1000 (see Figs. 3 and 4).

[0073. A simple connection by itself can be used to attach a bamboo culm or structural element 1000 to a plank for instance. Except for this latter, applications are very limited for a simple connection. Therefore, a natural development of the concept has been for the inventors to design “nodes” made of multiple simple connections. To this aim, two approaches have been undertaken, namely adding further branch pairs to a base 100 and physically connecting several clip connector devices. Of course, other approaches may be followed. Accordingly, the clip connector device of the invention has been further improved to fulfil these requirements and modified, depending on the needs, to comprise in some embodiments an additional pair of face-to-face branches 203, 204, each branch in said additional pair stemming from the second surface 102 of the base 100. A schematic configuration of this embodiment is shown in Figs. 5 and 6, for example for connecting two culms or structural element 1000. In another embodiment, schematically shown in Fig. 7, the clip connector device of the invention comprises one or more additional pair(s) of face-to-face branches 210, 211 , each branch stemming from a lateral portion of the base 100. This embodiment allows the plugging of several structural elements 1000, for example four in the configuration of Fig. 7. Of course, this is only an example and the construction of Fig. 7 may be adapted to allow the connection of less structural elements 1000 or more structural elements 1000. The disposition of the branches may not be identical to the one illustrated in Fig. 7 and the angles separating each pair of branches may be different. [0074. In an alternative or additional embodiment, the clip connector device of the invention has a base 100 comprising connection means adapted and configured to connect at least one of 1) two or more clip connectors between them and 2) a clip connector with a structural element. As a way of example, the clip connector device of the invention may comprise connection means formed in one embodiment from a plurality of posts 500 defining a toothed pattern on a surface of the base, as shown for instance in Figs. 2 to 4. The toothed pattern advantageously permits to connect clip connector devices between them and/or with a structural element 1000 without having to use glue, thereby reducing costs, facilitating the connections (especially for 3D nodes) and improving resistance at the nodes interface. For example, a toothed pattern 500 could be used to form a connector device similar to that of Fig. 5 from two individual connector devices as illustrated in Fig.1 , or the configurations of Figs. 7 or 8 using a plurality of connector device of Fig. 1 attached by their bases 100. This is particularly useful for 3D-printed connection clips, where 3D printed objects are made of a superposition of printing layers, and therefore the resistance of the printed object is way higher in the direction of printing. Advantageously, an additional structural element 2000, as depicted for instance in Fig. 8, can be added as a node interface to mechanically couple the various devices between them to even better distribute the coupling forces of the interconnected clip devices and assemblies.

[0075. In an alternative or additional embodiment, the clip connector device of the invention comprises connection means having a threaded member or pattern, such as a screw-like element 501 or a nut-like element 502. These embodiments are represented in Figs. 9 to 15. The main advantage of these configurations resides in the possibility to have a tighter interconnection between the connection clip and a structural element in an assembly, or between two connection clips, so to reduce as much as possible the risk of mechanical failure. For instance, a node comprising a plurality of connection clips can be obtained by screwing said connection clips to a mating structural node interface 2000 (Fig. 14). In another scenario, two connection clips can be assembled to obtain a 4-branched connection clip as depicted in Fig. 15, wherein one 2-branched 201 , 202 clip comprising a screw-like element at its base is screwed on the second 2-branched 203, 204 clip, comprising in turn a nut-like element base.

[0076. Another aspect of the present invention relates to an assembly comprising: [0077. - a clip connector device according to the present disclosure and

[0078. - a structural element 1000/2000 (see Figs. 4, 6 and 8). Still a further aspect relates to a kit comprising a clip connector device according to the invention and a connection element selected for example from a threaded node, a toothed node and a screw configured to reduce unclipping of the clip device. The kit is typically provided in a package together with instruction for connecting the various parts together.

[0079. In one embodiment, the structural element 1000/2000 comprises a plurality of recesses configured to mate with a plurality of posts 500 of the clip connector device. This design and configuration is particularly advantageous for connecting a connector device to a structural element 1000/2000 that cannot be modified to include thru holes or bores, such as a base fixed to the floor. Additionally or alternatively, the structural element 1000 is a tubular element, like a bamboo culm, comprising at least a pair of opposed bores 1100 configured to mate with the blocking buttons 301, 302 of the clip connector device once they are assembled. Combinations of these two embodiments can of course be envisaged, as it will be evident to a skilled person. The posts 500 may also be used to form the connector device of figure 5, using two connector devices according to figure 2. The posts 500 are therefore used to attached both devices together rather than one connector device to a structural element. The posts 500 may be used in other embodiments of the present invention, for example to form the constructions as illustrated in figures 7 or 8. According to some additional or alternative embodiments, a structural element 1000, including a node interface 2000, comprises a threaded member or pattern configured to mate with a threaded member or pattern, such as a screw-like element 501 or a nut-like element 502, of the clip connector device. Other equivalent means may be used to attach (removably or not) a clip device to a node interface. Exemplary embodiments are represented in Figs. 9 to 14. The main advantage of such embodiments resides in the possibility to have a tighter interconnection between the connection clip and a structural element in an assembly, so to increase the stiffness and reduce the slack, thereby reducing as much as possible the chance of mechanical failure. For instance, Fig. 13 shows an assembly comprising a clip device having a nutlike member 501 at the distal end of its base 100 connected to a flat support 1001 comprising a screw 1002. The clip is screwed around screw 1002 at one end, and connected to an elongated structural element 1000, such as a bamboo culm, at the opposed end through branches 201 and 202, contacting the culm 1000 at the level of its bores 1100 via the clip buttons 301 and 302. Fig. 11 shows an assembly comprising a clip device having a nut-like member 501 at the distal end of its base 100 connected to a node interface 2000 via a screw 1002; Fig. 12 shows a similar embodiment of an assembly wherein a clip device having a screw-like member 502 at the distal end of its base 100 is connected to a node interface 2000. The clip device is for example as illustrated in figure 10.

[0080. As it will be apparent, still another object of the present invention relates to the use of a clip connector device or of an assembly according to the present disclosure for the fabrication of an article of manufacture, as well as the article of manufacture obtainable by such a fabrication. Said article of manufacture may be for instance one of demountable bikes, bamboo bikes, scaffoldings, fences, games for children, bamboo tents, trusses for construction structures, shadow devices, verandas and furniture, to cite a few non-limiting examples.

[0081. While the invention has been disclosed with reference to certain preferred embodiments, numerous modifications, alterations, and changes to the described embodiments, and equivalents thereof, are possible without departing from the sphere and scope of the invention. Accordingly, it is intended that the invention is not limited to the described embodiments, and be given the broadest reasonable interpretation in accordance with the language of the appended claims.

[0082. Exemplary embodiments have been described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the systems and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the systems and methods specifically described herein and illustrated in the accompanying drawings are nonlimiting exemplary embodiments and that the scope of the present invention is defined not solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention. A number of problems with conventional methods and systems are noted herein and the methods and systems disclosed herein may address one or more of these problems. By describing these problems, no admission as to their knowledge in the art is intended. A person having ordinary skill in the art will appreciate that, although certain methods and systems are described herein, the scope of the present invention is not so limited. Moreover, while this invention has been described in conjunction with a number of embodiments, it is evident that many alternatives, modifications and variations would be or are apparent to those of ordinary skill in the applicable arts. Accordingly, it is intended to embrace all such alternatives, modifications, equivalents and variations.