Flexible space frames, components thereof and methods of construction

Abstract

To provide a system of cross-shaped units and nodes used to construct strong, lightweight, and inexpensive space frames using rigid and flexible components alternately.SOLUTION: Provided is a cross-shaped member for constructing a space frame. The cross-shaped member includes a cross-shaped component with four equidistant arms, each extending outward toward the distal end. Each end includes an integrated connector component designed to be connected to other connector components. Each connector component includes a distal connection pin with a locking ledge and beveled edge, a distal connection hole, a short side alignment pin, a short side alignment hole, a long side alignment pin, a long side alignment hole, a channel, and a semicircular protrusion. The pair of connector components are connected using the side alignment pins and the side alignment holes to form a connector component assembly 39 having two distal connection pins and two distal connection holes.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to flexible space frames, their components and methods of construction. [Background technology]

[0002] The present invention is a lightweight, strong, flexible space frame and an adjustable method for constructing such a frame.

[0003] Modular framing systems are known for applications in aerospace vehicles and structures, as well as ground construction and robotics. For example, U.S. Patent No. 1,410,876 to Bell et al. teaches an interlocking kite-shaped tetrahedron structure for an airborne vehicle or structure. More recently, U.S. Patent No. 5,097,645 to Sanderson.

[0004] Space frames are useful because they offer a structural solution that is not found in the linear frame construction of many typical buildings and structures. Space frames provide versatile, lightweight structures that are aesthetically pleasing and easy to build. They are often used for rooftop framing, pergolas, or anywhere you are trying to project a sophisticated or space-age feel.

[0005] Currently known space frame models require the use of specially designed struts made from metal alloys, which are rigid and cannot move freely within the assembled frame in response to airflow and other stresses. These frame components are often constructed from expensive metals, making distribution difficult, leading to logistical challenges and increased costs. As is well known in civil and industrial engineering, the overuse of rigid materials—whether in buildings, vehicles, or machinery—is prone to fracture and failure when subjected to wind, water, torsion, acceleration, or other environmental stresses. The degree and location of flexibility within a structure is determined by architects and engineers. In modular construction, best practice is to allow designers to choose which points within the larger design are flexible or rigid, allowing for a structure that can best respond to the types of environmental stresses expected. For example, a particular structure can remain rigid when forces are applied from one direction, but flex when forces are applied from another or opposite direction. Summary of the Invention [Problem to be solved by the invention]

[0006] Currently known space frame technology lacks a combination of rigid and flexible components that allows forces applied to the rigid components to be transferred to the flexible components and distributed evenly throughout the structure. The invention taught herein addresses this lack of flexibility. [Means for solving the problem]

[0007] In a preferred embodiment, a cross-shaped member for constructing a space frame is provided, the cross-shaped member having cross pieces with four equidistant arms each extending outwardly toward a distal end, each end having an integral connector part designed to interlock with another connector piece, each connector piece having a distal connecting pin with a locking ledge and a beveled edge, a distal connecting hole, a short side alignment pin, a short side alignment hole, a long side alignment pin, a long side alignment hole, a channel, and a semicircular protrusion, a pair of said connector pieces interlock using said side alignment pins and said side alignment holes to form a connector piece assembly having two distal connecting pins and two distal connecting holes.

[0008] In another preferred embodiment, the cruciform members described herein are constructed from a durable yet flexible material from the group including shape memory alloys, shape memory polymers or shape memory copolymers.

[0009] In another preferred embodiment, the cruciform member described herein has a cross and four arms fabricated from the group consisting of a shape memory alloy, shape memory polymer, or shape memory copolymer, and four connector parts fabricated from a non-shape memory metal alloy or polymer.

[0010] In another preferred embodiment, the cruciform members described herein are made from injection molded plastic.

[0011] In another preferred embodiment, a cruciform member as described herein, wherein said cruciform member is manufactured by three-dimensional printing.

[0012] In another preferred embodiment, in a cruciform member as described herein, the connector parts interlock using applied pressure only.

[0013] In another preferred embodiment, a space frame having a plurality of frame units, each of said units being connected by a snap-fit ​​connection between their respective connector component assemblies, said units comprising: (i) a spherical unit consisting of six cross-shaped members according to claim 1, wherein each connector part is adapted to couple with another connector part to form a total of twelve connector part assemblies and six convex surfaces, and each pair of connector parts is adapted to couple with the distal connection pin and distal connection hole to form a connector part assembly having two long side pins, two short side pins, two long side holes, and two short side holes; (ii) an inversion unit in which each cross-shaped member is inverted to form six concave surfaces, and each pair of connector parts is interlocked by inserting a side alignment pin into a corresponding side alignment hole to form 12 connector part assemblies, each connector part assembly being locked by two overlocking blocks and having two distal connection pins and two distal connection holes; A space frame is provided, wherein the space frame is selected from the group consisting of:

[0014] In another preferred embodiment, the space frame described herein has a plurality of tetrahedral units, each of which has a spherical unit disposed within it.

[0015] In another preferred embodiment, the space frame described herein comprises a plurality of octahedral units, each of which has a spherical unit disposed therein.

[0016] In another preferred embodiment, there is provided a method of manufacturing a space frame, comprising the steps of: (1) manufacturing the cruciform member of claim 1, wherein the cross and four arms are formed from the group consisting of a shape memory alloy, a shape memory polymer, or a shape memory copolymer, and the four connector parts are formed from a non-shape memory metal alloy or polymer; (2) A process for creating a frame unit, which frame unit is (i) a spherical unit made up of six cruciform members, each connector part being coupled with another connector part to form a total of twelve connector part assemblies and six convex surfaces, each pair of connector parts being coupled using the distal connection pins and distal connection holes to form a connector part assembly with two long side pins, two short side pins, two long side holes, and two short side holes; (ii) an inversion unit in which each cross-shaped member is inverted to form six concave surfaces, and each pair of connector parts interlocks with each other by inserting side alignment pins into corresponding side alignment holes to form 12 connector part assemblies, each connector part assembly having two distal connection pins and two distal connection holes, and finally, two overlock block snap-fit ​​covers to connect the connector parts; (3) connecting each of said units to one or more other units by a snap-fit ​​connection between the connector component assemblies of each of said units; A method is provided, comprising:

[0017] In another preferred embodiment, there is provided a node for constructing a space frame, the node having two or more helical cruciform members, each member having four arms, each member having one or more grooves that allow two or more of said members to reversibly connect at an interface joint, and each arm including a C-channel cut along its axis whereby each arm accommodates a rod for connecting the node to other nodes.

[0018] In another preferred embodiment, the nodes described herein have three cross-shaped members with a total of 12 arms, thereby providing 12 attachment points to other nodes.

[0019] In another preferred embodiment, in the nodes described herein, each cruciform member is fabricated from the group consisting of a shape memory alloy, a shape memory polymer, or a shape memory copolymer.

[0020] In another preferred embodiment, in the nodes described herein, each cruciform member is permanently attached using a melt, adhesive, or similar bond. [Brief explanation of the drawings]

[0021] [Figure 1] Figure 1 shows a diagram of a cruciform member with connector pieces at each end. The flattened sections form the struts of the final structure. The ends of the member are used to connect to other cruciform members or other fittings designed for various applications. This cruciform member can be manufactured using a plastic injection mold or 3D printed. [Figure 2] FIG. 2 is a diagram showing an alternative configuration of the cross member of FIG. 1 in which the member is inverted and bent. [Figure 3] FIG. 3 is a diagram showing the interlocking design of two cross-shaped member connector parts. [Figure 4] FIG. 4 is a diagram showing two aligned connector parts that further include two optional single-barrel crimp sleeves 61 that clamp the connector rods.

[0022] [Figure 5A] FIG. 5A is a diagram showing six cross-shaped members locked together to form a spherical unit.

[0023] [Figure 5B] FIG. 5B is a diagram showing multiple cruciform members locked together to form an alternative inversion unit, also consisting of six cruciform members.

[0024] [Figure 6] FIG. 6 is a diagram showing the mating connector parts of the two spherical units.

[0025] [Figure 7] FIG. 7 is a diagram showing two spherical units joined together in one connector part assembly.

[0026] [Figure 8] FIG. 8 is a diagram showing a frame made up of multiple linked spherical units, in which one cross-shaped member of some units is missing to form a top opening, and in another embodiment, the top opening of each unit faces in the same direction.

[0027] [Figure 9] FIG. 9 is a diagram showing a single cruciform member with helical curves and c-channels cut axially along each of the four arms.

[0028] [Figure 10] Figure 10 is a diagram showing an exploded view of a spirally curved c-channel node. Each of the three parts is identical, with the integral parts necessary to align and snap together two additional similar units.

[0029] [Figure 11] FIG. 11 is a diagram showing a fully assembled spirally curved c-channel node containing six c-channels that surround and circumnavigate a central point.

[0030] [Figure 12] Figure 12 is a diagram showing six fully assembled spirally curved C-channel nodes with rods emerging from each node and tying to other similar nodes.

[0031] [Figure 13] FIG. 13 is a diagram illustrating one potential frame assembly embodiment utilizing spherical, inverted, and spirally curved c-channel units together.

[0032] [Figure 14] FIG. 14 is a diagram showing the frame of FIG. 13, with one piezoelectric crystal inserted into the frame and another introduced into the matrix.

[0033] [Figure 15] FIG. 15 is a diagram illustrating an alternative embodiment of a frame assembly utilizing spherical units in combination with a tetrahedron-octahedron honeycomb structure. DETAILED DESCRIPTION OF THE INVENTION

[0034] The present invention comprises a modular space frame having multiple rigid components connected together using a flexible frame, where the flexible structure maintains its strength along the same strength lines as the rigid structure. Forces applied along vectors through the rigid frame are transferred to the flexible frame and distributed evenly throughout the flexible frame.

[0035] The level of flexibility and rigidity within the frame can be varied either by the choice of material or by its thickness. The flexible frame provided acts not only as a hinge or joint, but also as a cushion or shock absorber between two or more rigid components.

[0036] This flexible space frame construction method allows the entire frame to be constructed using a single modular part, one embodiment of which is shown in Figure 1. This method uses one part repeatedly, resulting in a strong, lightweight, and flexible frame. This frame construction method uses snap-fit ​​parts. For example, six identical cruciform members can form a spherical grouping. The frame can be constructed without adhesives, welded joints, loose pins, screws, or other permanent or non-permanent fasteners. However, such fastening methods can be used to increase the level of adhesive strength, if desired.

[0037] Each cruciform member snaps onto other similar members by mating the two connector assembly components together. As used in describing this invention, a "pin" is understood to be a typically cylindrical protrusion integrated into the larger structure of the cruciform member for the purpose of attachment to other similar members. The connecting pin of one member is positioned into a hole in the other. The two are then pressed together to either (1) align the larger component for attachment by a second method, such as part 70 shown in FIG. 6, or (2) snap into place once fully inserted.

[0038] Six such cruciform members can be aligned, bent, and connected into multiple designs, each having a "unit." Examples of such unit designs include a roughly spherical unit 50 with six convex sides, an inverted unit 51 with six concave sides, and an open-top spherical unit 52.

[0039] In the spherical unit example, the two spheres can be aligned with any of the 12 connector component assemblies 39 spaced around the sphere. These alignment points allow the two spheres to be connected together. Again, aligning pins and holes allows the two units to be held together. The two spheres can be secured in place by attaching an overlocking structural block 70 at the intersection (see Figure 7). The same attachment method can be used with other unit designs. More units can be added to build larger, stronger structures of any configuration. A fully constructed frame can utilize only a single unit design or incorporate two or more such designs. The resulting frame structure maintains flexibility while allowing connector rods to be added and secured in various ways to add high stiffness to specific areas within the flexible structure.

[0040] This space frame construction method employs a rigid space frame construction method, as described above, attached in conjunction with a flexible frame. The disclosed method uses multiple iterations of a single component to create a strong, lightweight, and rigid structure. Another cross-shaped member, different from the one used above, is used to fabricate a 12-point (6-channel) star node. In this case, three cross-shaped members, all of the same shape and size, are joined to form one node of the 12-point star. This star node is used in combination with wood, plastic, metal, and / or carbon fiber rods to form a rigid space frame using a snap-fit ​​mechanism built into the design. This rigid frame can optionally be constructed without adhesives, welded joints, loose pins, screws, or other permanent fasteners. Each cross-shaped member is constructed with two C-channels. The C-channels are designed to snap onto flexible or semi-flexible rods or insert end-on into the channels. Typical materials for flexible or semi-flexible rods are composed of wood, plastic, metal, fiberglass, or carbon fiber, or other similar materials that exhibit varying degrees of stiffness and durability while also considering flexibility. Flexible or semi-flexible rod materials are selected and / or mixed taking into account the desired degree of flexibility and the level of stress expected in a given structure. The purpose of the nodes is to allow the user to weave semi-flexible rods into a space frame, as shown, for example, in Figure 10. Friction holds the rods in place and prevents them from sliding axially, while a rigid space frame is formed, to be used by itself or in combination with other frames described herein.

[0041] Applicant's disclosed manufacturing method eliminates the need for complex molds and manufacturing processes that increase the cost of the final product. Because the final product has a 12-sided shape, injection molding or similar processes would require a 12-sided mold and specialized, complex manufacturing processes. Therefore, a cost-effective manufacturing process such as that described herein would have significant market utility.

[0042] The disclosed method provides simplicity so that unskilled workers can quickly and easily install and assemble the frame. Given the relatively small size of the units, few tools are required for assembly. Thus, units up to a certain size can be assembled without tools, welding, or adhesives, and disassembly is similarly simple, requiring few or no tools.

[0043] Shape memory alloys (SMAs) and shape memory polymers (SMPs) are known to provide desired flexibility to space frame invention components, preferably the cross sections and / or arms of a cruciform member. SMAs, such as nickel-titanium, nickel-aluminum, copper-aluminum-nickel, beta-titanium alloys such as Ti-Nb, Ti-Mo, and Ti-V, and beta-brass alloys such as Cu-Zn-Al, are currently used in medical devices, robotics, industrial design, and, increasingly, construction. Flexible space frame components made from SMAs may exhibit one-way or two-way memory effects. In the latter case, the component can be stored and transported at a first temperature in a shape that facilitates storage and transportation, and then assume a different, second shape when deployed at a second temperature, such as the extreme cold of outer space.

[0044] Several known polymer and copolymer types exhibit shape memory properties and may be useful for fabricating cruciform members. Perhaps the best known and most studied SMPs are polyurethane polymers, but other known SMPs include cross-linked polyethylene homopolymers, styrene-butadiene thermoplastic copolymers, polyisoprene, classes of copolymers containing stearyl acrylate and acrylic acid or methyl acrylate, norbornene or dimethaneoctahydronaphthalene homopolymers or copolymers, and styrene copolymers.

[0045] SMPs and SMAs have been the subject of commercial development over the past 20 years. The name SMP comes from their ability to return to their original, "memorized" shape after undergoing a deformation. In this invention, the use of SMAs or SMPs to fabricate belt-like structures of cross-shaped members allows those members to bend, twist, or deform within their unit structure, thereby absorbing the application of forces that might otherwise damage or destroy the larger frame, and returning to their original configuration after such an impact occurs, maintaining the integrity of the frame.

[0046] Construction of Applicant's frame components may be accomplished using injection molding, 3D printing, or similar techniques commercially used for metals and plastics.

[0047] The final structure can have an infinite number of configurations, thus allowing the final structure to have multiple shapes.

[0048] In one embodiment, the structure is based on a face-centered cubic lattice of spheres and a tetrahedron-octahedron honeycomb of rectilinear lattices, with each node having an equal diameter, forming a space-filling arrangement of interconnected spheres, which can be fabricated using three-dimensional printing technology (see, for example, Figures 12 and 14). The final structure can fill empty space without colliding with itself. Two adjacent rigid space frames with similar tetrahedron-octahedron honeycomb designs can be connected with a flexible frame. These two rigid frames have the advantage of being able to move simultaneously or swing independently while still being connected. For example, this can be used to connect two floating rigid structures. Finally, two rigid structures can be connected and move independently while remaining connected.

[0049] The ease of tool-free assembly allows frame structures to be constructed on-site, even in challenging environments, without the need for extensive prefabrication. This allows the frame to remain modular and be stacked for storage during transportation. Similarly, frame units can be unsnapped and disassembled, requiring little to no tools. This therefore enhances the ease of on-site maintenance of the frame, as single units can be removed and replaced, and the entire frame reconfigured with minimal difficulty.

[0050] The ease of constructing and reconfiguring frame structures provides the ability to change frame geometry or to change units of one material or type for units of another as needed.

[0051] Shape memory materials may not be suitable for manufacturing the connector components to prevent the larger frame units from coming apart. In another embodiment, the connector components are made of known hard alloys, ceramics, polymers, or copolymers and connected to each arm end by known integration processes such as adhesives, welding, or similar stress-resistant attachment methods.

[0052] When either nitinol or piezoelectric crystals are introduced along one direction of the final structure, they can bend with changes in temperature or current. This capability can be used in a variety of applications, from lifts and joints to large mechanical muscles. Piezoelectric crystals are preferably used within the matrix as a means of introducing mechanical control of the matrix. Piezoelectric crystals are well known and used in industry due to their unique ability to change shape, deform, distort, contract, or expand when an electric current is applied. This property of the crystals not only serves the purpose of shape-changing, but they also exhibit significant strength relative to their size and weight. Thus, small crystals can lift several times their own weight without permanently degrading their structure. On the downside, these crystals have limited movement and shape-deformation properties, limiting their usefulness as mechanical muscles. However, they are also employed in many other technologies. They are currently used in printers, copiers, communications, pneumatic machines, and a variety of other technologies. This invention introduces a new application for these crystals, enabling their use in mechanical muscles.

[0053] This invention uses "sites" throughout its structure to create a large, flexible frame. Sites can be created at any point, allowing for the attachment of piezoelectric crystals between two points, while maintaining flexibility. Piezoelectric crystals can be installed anywhere according to the designer's requirements. Once installed in the structure, the piezoelectric crystals are attached and secured to the structure. Wires connect the crystals to a power source and control center, supplying electricity to the crystals where movement is required. The powered piezoelectric crystals then pull or push the frame, initiating bending, twisting, contraction, or expansion of the entire frame. The resulting structure can lift and move significant amounts of mass without the need for complex and heavy hydraulic or pneumatic systems, gears, shifters, relays, motors, or shafts. Furthermore, because the sensitive crystals are protected by the flexible cushioning of the frame, there is little risk of damage to the crystals even when excessive force is applied.

[0054] The resulting frame is lightweight, flexible, maneuverable, and easy to construct, and it can function as a mechanical muscle. Furthermore, stiffness can be introduced into any part of the frame as needed, allowing the frame to have simulated bone properties. The resulting structure thus possesses a mechanical muscle system alongside a rigid skeletal system, with the ability to couple the two systems, allowing the completed structure to function like an integrated musculoskeletal system with all the properties.

[0055] Power for the piezoelectric crystal can be derived from known commercial technologies, particularly alkaline batteries, lithium ion or other known chemistry batteries, solar panels, or any other known power source that can be suitably sized and mounted on the frame.

[0056] Space frames for use on space stations can be used as a means of storage while also providing protection from the natural forces of space. For example, a flexible frame with the natural shape of a sphere could provide a means of holding an array of spherical tanks, providing compartmentalization similar to that used on large ocean-going ships. If this array is used to store water, fuel, and food, the additional mass added to the frame helps protect the space station from the effects of small meteors and possibly radiation. If damage occurs, it is limited to a small area that can be easily repaired. Loss of cargo is limited to the impacted ship, leaving the rest of the ship intact, so the loss is minor. A similar incident with a larger tank would result in a complete loss of the entire ship's stores.

[0057] The invention described herein contrasts with known frame technology in that it exhibits a high degree of flexibility along its axis. For example, the disclosed units deform to absorb the stress of a force applied axially along one of the connector rods or radially across the frame before returning to their original configuration due to the shape-memory components. Furthermore, the method of manufacture differs from known technology in that the cruciform members bend like a spring and are attached together at their tips, whereas known designs require fasteners such as slots cut into the base, pins, bolts, screws, or similar means. Therefore, the frame allows units of any configuration to be directly joined to each other without the need for connecting rods, pins, or other separate connecting components. The inherent flexibility of the larger frame also compensates for small misalignments or imperfections in the components themselves.

[0058] The flexibility of Applicant's frame also allows it to flex while being assembled, further facilitating construction. The frame utilizes a single repeating unit that can be manufactured quickly with known techniques, and the unit can be efficiently stored and assembled on-site, resulting in low manufacturing, distribution, assembly, and maintenance costs for the frame. Additional parts require more molds, additional packaging, and increased final costs.

[0059] Detailed explanation of the diagram FIG. 1 shows a ventral view of a cruciform member 20 with a central cross piece 21 and four equidistant arms 23 extending outward toward a connector component 30, each of which is located at one end of the four arms. Each connector component is generally rectangular, having a proximal face 30a and a distal face 30b, two side faces 30c, and a dorsal face 30d (not visible) and a ventral face 30e. Each arm end 21 is used to connect to another cruciform member 20 or other fitting designed for various applications. Each connector component 30 is raised ventrally above its corresponding arm 23, each including a distal connection pin 31 extending from the distal face 30b of the connector component and a distal connection hole 32 for receiving a distal connection pin of another connector component, with such distal connection pin 31 including a ledge 31a and a beveled edge 31b for connecting to another connector component via a snap fit. Each connector part has a complementary pair of long and short side alignment pins 33 and 35 and long and short side alignment holes 36 and 34, respectively, located on the ventral surface 30e for alignment of the connector parts, and also has a channel 37 and a semicircular protrusion on each side. The cross-shaped member 20 can be manufactured by plastic injection molding or 3D printing.

[0060] Figure 2 shows the rear cruciform of the cruciform 20 shown in Figure 1. In particular, the rear surface 30d of each connector component 30 is depicted, showing the openings of each of the long and short side alignment holes 34 and 36 in such rear surface.

[0061] FIG. 3 shows two connector parts 30 entering a snap-fit ​​connection, with the distal contact pin 31 of each connector part inserted into the distal contact hole of the opposing connector part.

[0062] Figure 4 shows two connector parts 30 with two single-barrel crimp sleeves 61 exiting from either side and connector rods 60 inserted through crimp sleeve holes (not shown). The collet mechanism is fully depicted in Figure 10. In alternative embodiments, adhesive, heat shrink, or welding can be used in place of the crimp sleeves. Crimp sleeves are not necessarily required unless positive control is required for the connection between the flexible and rigid frames. For example, if the connection point is between two floating platforms, the designer can use crimp sleeves to allow free movement at the joint.

[0063] FIG. 5A shows a fully formed spherical unit 50 including six cruciform members 20, each connected to four other cruciform members using the distal connection pins 31 and distal connection holes 32 of its four connector parts 30, creating six convex cruciform surfaces that together form a rough sphere. In this configuration, the ventral surface 30e of each connector part faces outward, and the dorsal surface 30d faces inward. This configuration forms 12 connector part assemblies 39, each consisting of two connector parts 30, with the long and short connection pins 33, 35 and long and short connection holes 34, 36 on the ventral surface 30e of each connector part facing outward. This design allows the spherical unit 50 to be further connected to other units.

[0064] 5B shows an alternative configuration of the spherical unit of FIG. 4A, where the connector parts 30 of the six cruciform members 20 are interlocked using long and short connecting pins 33, 35 and long and short connecting holes 34, 36 on the ventral surface 30e of each connector part (all such connecting parts are hidden in the figure). The resulting inverting unit 51 includes six concave cruciform surfaces that form a star-like shape with twelve connector part assemblies 39 forming points, each containing two interlocking connector parts 30 and featuring two outwardly facing distal connecting pins 31 and distal connecting holes 32, allowing further connection of the inverting unit 51 to other units.

[0065] 6 provides a close-up view of the connector component assemblies 39 of two individual spherical units 50 as they approach for mating, with arrows indicating the mating snap-fit ​​of each long and short connecting hole 34, 36 of a connector component assembly with the corresponding long and short connecting pins 33, 35 of the opposite connector component assembly. The listed pins and holes are aligned such that the connector component assemblies are locked together using an overlocking block 70, as shown, for example, in FIG.

[0066] FIG. 7 shows two spherical units 50 connected by the process depicted in FIG.

[0067] 8 shows an alternative frame embodiment in which multiple spherical units 50 are connected to other partially formed open-top spherical units 52. The open-top spherical units 52 are formed from five cruciform members 20 instead of six, and when one cruciform member 20 is removed from the open-top spherical unit, each such cruciform member remains unsecured within the unit itself, thus leaving a top opening 52a. As shown, multiple open-top spherical units are interconnected using the snap-fit ​​design of their respective connector component assemblies 39, which are secured in place using overlock blocks 70.

[0068] FIG. 9 shows a single helical cruciform member 41 with c-channels 44 cut into each of the helical cruciform member's arms 42 along its axis. The figure also shows interface fittings 45 and grooves 43 that allow for the insertion of other similar cruciform members. The interface fittings 45 are the receiving portion of the other similar cruciform members. All three similar members are aligned and set along this axis. Grooves 43 cut perpendicular to the member's arms 42 allow each groove to align with a groove on another similar member. These grooves are specially shaped to removably snap onto and retain the arms of the other similar members.

[0069] 10 shows an exploded view of node 40. Such a node consists of three helical cruciform members 41, all of which join at each of the other two joints. These three cruciform members are then locked into place using a snap-fit ​​mechanism, where light tension is applied to the arms of one member, and each snap-fit ​​mechanism engages an interlocking groove 43. A helical cruciform member ledge 46 is located at the end of each groove to prevent unintentional disengagement of the interlocked members.

[0070] Figure 11 shows a fully formed node 40. Each of the 12 pointed nodes has six channels, including three internal channels 47 and three external channels 48, all oriented around one central point of intersection 49. The node is held together by a snap-fit ​​mechanism, allowing each node to be later disassembled and broken down into its component parts; however, if desired, the nodes can be permanently secured together using glue, adhesive, or welding.

[0071] Figure 12 shows a set of six nodes 40 with connecting rods 60 joined together to form a tetrahedron-octahedron honeycomb structure. Each node has a total of six connecting rods passing through each of six channels 47, 48. The rods run the entire length of the structure and penetrate several nodes. The gaps in the C-channels 44 are significantly smaller than the diameter of the rods, allowing the rods to be pushed and snapped into the channels. Friction prevents the nodes from sliding axially. If the rods attempt to move axially along the channels, the torsional curvature of the channels creates significant friction. This friction therefore prevents the rods from moving axially, but allows some freedom of axial movement. Two crimp sleeves 61 can be crimped onto the connecting rods 60 to secure the rods and prevent axial movement. One such sleeve is attached to the end of each arm. The use of crimp sleeves is at the discretion of the designer or engineer and is not strictly required. FIG. 13 shows a frame made up of multiple linkage units as described herein, including spherical units 50, inverted units 51, and connecting rod holding nodes 40.

[0072] Figure 14 shows the same frame as in Figure 13 with two piezoelectric crystals. One crystal is mounted on the frame and the other crystal is attached to the frame in-situ. In this case, the site is between two adjacent connector component assemblies 39 and is represented by a hollow rectangular prism. Figure 6 shows an alternative configuration consisting of six interlocking cruciform members 20 that, when joined, form a spherical unit 50.

[0073] FIG. 15 shows an alternative embodiment of multiple spherical units 50 arranged within an octahedral unit 54 to form a honeycomb frame that functions as a single structure with both flexible and rigid properties.

[0074] (List of reference numbers) 10 Frame System 20 Cross-shaped member 21 Arm end 22 Cross part 23 Arm 30 Connector parts 30a Proximal surface 30b distal surface 30c side 30d back 30e ventral surface 31 Distal connecting pin 31a protruding part 31b Sloped edge 32 Distal connection hole 33 Side alignment pin (long) 34 Side alignment hole (short) 35 Side alignment pin (short) 36 Side alignment hole (long) 37 channels 37a Rod hole 38 Semicircular protrusion 39 Connector Assembly 40 nodes 41 Spiral cruciform member 42 Spiral cruciform member arm 43 Groove 44 C-channel 45 Interface joint 46 Spiral cross member protrusion 47 Internal Channels 48 External Channels 49 Intersection 50 spherical units 51 Reversing unit 52 Top-opening spherical unit 52a Top opening 53 Star Unit 54 Octahedral Unit 60 Connector rod 61 Crimp sleeve 70 Overlock Block

[0075] The references cited herein are incorporated herein in their entirety, particularly as they relate to teachings of the level of ordinary skill in the art and any disclosure necessary for a general understanding of the claimed subject matter. It will be apparent to those skilled in the art that modifications or insubstantial changes may be made to the above-described embodiments without departing from the scope of the invention. The scope of the invention is therefore determined by the following claims and their equivalents.

Claims

1. A node for constructing a three-dimensional frame, a plurality of helical tubular members, each helical tubular member comprising: a C-shaped channel formed therein along the longitudinal axis of the helical tubular member; a plurality of connecting grooves formed on the outer circumferential surface of the helical tubular member, the plurality of connecting grooves comprising a central connecting groove formed in the center of the helical tubular member, a first connecting groove formed at a position spaced a predetermined distance from the central connecting groove along the longitudinal axis of the helical tubular member, and a second connecting groove formed on the outer circumferential surface opposite to the first connecting groove, the second connecting groove being spaced a predetermined distance from the central connecting groove along the longitudinal axis of the helical tubular member in a direction opposite to the first connecting groove; the plurality of helical tubular members, a connecting rod extending through the C-shaped channel of each of said helical tubular members; and the central coupling groove, the first coupling groove, and the second coupling groove of each of the helical tubular members have complementary shapes for releasably snap-fittingly connecting the helical tubular members to one another; the plurality of helical tubular members are configured such that a central connecting groove of one helical tubular member is snap-fitted into a corresponding central connecting groove of another helical tubular member, thereby forming a cross-shaped member between the two helical tubular members; the two helical tubular members define four arms extending outwardly from a central portion of the cross-shaped member; the node has a plurality of the cross-shaped members, and each cross-shaped member has a first coupling groove portion of each helical tubular member snap-fitted into a corresponding second coupling groove portion of each helical tubular member of another cross-shaped member to form one node; the connecting rods are configured to extend through the C-shaped channels of each helical tubular member of one node and each helical tubular member of another node, thereby connecting the nodes together to form a space frame; node.

2. 10. The node of claim 1, wherein the node has six helical tubular members; The six helical tubular members further include three inner helical tubular members each including a C-shaped inner channel and three outer helical tubular members each including a C-shaped outer channel.

3. 10. The node of claim 1, wherein the node has six helical tubular members defining a total of twelve arms, thereby providing twelve attachment points to other nodes.

4. 10. The node of claim 1, wherein each helical tubular member is constructed from a material selected from the group consisting of a shape memory alloy, a shape memory polymer, or a shape memory copolymer.

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