The present invention relates broadly to deployable structures and an assembly comprising a plurality of deployable structures.
Deployable structures, for example, space frames, beam structures, etc., are required in a wide variety of applications. These structures are usually transported in a folded state to a chosen site for deployment. After use, they may be folded back and stored for redeployment.
In general, conventional deployable structures suffer from poor structural configurations in a fully deployed state. Many conventional foldable structures deploy into non-optimal shapes as the requirement for the structure to be foldable imposes geometric constraints that are sometimes contrary to structural requirements. Further, the deployable structures may be bulky in a folded state, and are mechanically complex in design.
Typical self-stabilizing or “clicking” or “self-locking” deployable structures do not provide structurally optimal forms in the fully deployed state. Some of them require enormous forces and coordination for deployment and undergo significant bending during deployment. Other forms of structural systems require a large number of individual components and complicated assembly operations to form the structure, making deployment or folding the structures time consuming and costly.
In accordance with a first aspect of the present invention there is provided a deployable structure comprising:
a plurality of pairs of hingeably connected members,
a first hinge element; and
a second hinge element;
wherein the two members of each pair of hingeably connected members are connected to the first and the second hinge elements respectively; and
wherein the first hinge element is capable of being stabilized for facilitating stabilization of the deployable structure into a deployed state.
The deployable structure may further comprise:
a central member wherein the first and second hinge elements are connected to different ends of the central member; and
wherein one portion of the first hinge element is detachably connected to the central member such that the first hinge element is stabilized when connected to the central member.
The deployable structure may further comprise a fastening element to fasten the first hinge element to the central member.
The deployable structure may comprise three or more pairs of hingeably connected members.
One of the two members in each pair of hingeably connected members may be connected to the other member of said pair by at least one third hinge element.
The deployable structure may further comprise cables or flexible elements connecting the third hinge elements.
One of the two members in each pair of hingeably connected members may connected to the other member of said pair via one or more secondary members.
The secondary members may be substantially parallel to an imaginary line joining the first and second hinge elements, when the deployable structure is in the deployed state.
The hinge elements may allow a single degree-of-freedom of movement.
The members may comprise one or more of a group comprising struts, rods, tubes, telescopic elements, self stabilizing elements and cables.
The deployable structure may further comprise one or more energy stored devices for facilitating deployment and/or folding of the deployable structure.
In accordance with a second aspect of the present invention there is provided an assembly comprising a plurality of deployable structures, each deployable structure comprising:
a plurality of pairs of hingeably connected members,
a first hinge element; and
a second hinge element;
wherein the two members of each pair of hingeably connected members are connected to the first and the second hinge element respectively; and
wherein the first hinge element is capable of being stabilized for facilitating stabilizing the deployable structure in a deployed state.
Each deployable structure may further comprise:
a central member wherein the first and second hinge elements are connected to different ends of the central member; and
wherein one portion of the first hinge element is detachably connected to the central member such that the first hinge element is stabilized when connected to the central member.
The assembly may further comprise at least one cable or connecting the plurality of deployable structures.
The at least one cable or may connect hinge elements of the plurality of deployable structures.
Embodiments of the invention will be better understood and readily apparent to one of ordinary skill in the art from the following written description, by way of example only, and in conjunction with the drawings, in which:
a is a schematic representation of a plurality of connected deployable structures according to another embodiment of the present invention;
b is a schematic representation of a plurality of connected deployable structures according to another embodiment of the present invention;
a is a schematic representation of a plurality of connected deployable structures according to another embodiment of the present invention;
b is a schematic representation of a plurality of connected deployable structures according to another embodiment of the present invention;
c is a schematic representation of a plurality of connected deployable structures according to another embodiment of the present invention;
Generally, the described embodiments relate to a structural system of foldable, deployable or collapsible structures made up of interconnected units that are extensible and collapsible into various structural shapes, for example, space frames, panels, columns, domes, vaults.
A schematic representation of a deployable structure 100 in an example embodiment is shown in
The hinges 104, 108, 112 allow the upper and lower elements 140, 150 to rotate in a single degree-of-freedom, acting as pin-joints, and enable deployment and folding of the deployable structure 100.
When the deployable structure 100 is in a deployed state, one end of a central element 130 is detachably connected to the upper elements 140 via the upper hinge 108, and the other end of the central element 130 is connected to the lower elements 150 via the lower hinge 104. This allows the deployable structure 100 to be folded or deployed by attaching or detaching the end of the central element 130 from the upper hinge 108. It should be appreciated that the central element 130 may be detachably connected to either the lower hinge 104 or the upper hinge 108 at one end or both ends. Alternatively, the central element 130 may comprise two sections (not shown) detachably joined with each end of the central element 130 attached to the upper hinge 108 and the lower hinge 104, respectively. The upper hinge 108 may have means for disengaging and engaging the detachable end of the central element 130, for example, a fastening mechanism (not shown) may be used to lock the detachable end of the central element 130 to the upper hinge 108 when the deployable structure 100 is fully deployed.
When the deployable structure 100 is in an upright, deployed state as shown in
The deployable structure 100 in
The basic unit shown in
In another example embodiment, upper hinges 1080 may be disposed between lower hinges 1040 and a network of cables or flexible members 1700 joining the middle hinges 1120, as shown in
By exploiting the flexibility of the cables or flexible members 170 to improve the foldability of the deployable structure 100, improved compaction of the structure 100 can be achieved, when the structure 100 is folded. Further, the use of the cables or flexible members 170 make the deployable structure 100 significantly lighter and stiffer, compared to conventional designs. The mechanical complexity of the structure is also minimised. The cables 170 also carry tensional loads efficiently and help to stabilise the geometry of the deployable structure 100. Furthermore, a wide variety of structural shapes may be created by varying the length of the cables 170. The cables 170 may be metallic or composite materials cables, fiber-based cables, etc.
A plurality of deployable structures may be connected and deployed to form structural systems. For example, a plurality of the deployable structures 300 may be connected in-line to form a beam 301, as shown in
In another example embodiment, a plurality of the deployable structures 350 may be connected in-line to form a beam 302, as shown in
Alternatively, a plurality of deployable structures 400 may be connected and deployed in an array to form space frames and vaults, as shown in
c illustrates another example embodiment with additional connecting cables 493 connecting the upper elements 407. It should be appreciated that the connecting cables 490, 493, may be in other forms, for example, elements.
Referring to
Alternative embodiments of the deployable structure are shown in
Vertical rods 620, shown in
Other types of connecting attachments may be added to the hinges to enable the attachment to other structural units or sheets or fabric material.
Alternatively, other forms of deployable structural units (e.g. 895) may be disposed between an upper middle plane 862 and a lower middle plane 864 of the deployable structure 800, as shown in
In another example embodiment, the deployable structure 900 may comprise cables 970 connecting the middle hinges 912 diagonally, as shown in
It will be appreciated by a person skilled in the art that numerous variations and/or modifications may be made to the present invention, as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects to be illustrative and not restrictive.
For example, the central element may have energy stored devices such as springs, that help in the deployment process. Various telescopic and cable-realized mechanisms may be used to assist the coordinated deployment of the structure. Springs may be incorporated into the hinges for the same purpose. The cables may also be spring loaded or may have elastic attachments to prevent entanglement during deployment of the structure.
The elements may be telescopic or telescopic and lockable to provide flexibility in configuring the structure.
Further, the deployable structures may be combined with structural kinematic chains to facilitate deployment.
The cables and/or the elements may be pre-tensioned to enhance the structural behavior of the unit.
Fabric, sheet and other forms of covering material may be attached to the rods or cables by introducing additional connectors or by designing their shape to facilitate direct attachment.
By using cables that fold and attachable members (e.g. struts) that do not constrain the design, the example embodiments described above allow the fully deployed state of the structure to be structurally optimal.
The structures in the example embodiments achieve quick installation with the minimal assembly operations. The structure is substantially free of stress during deployment and in the folded configuration.
Possible industrial applications of the deployable structures include a wide range of temporary and permanent structures such as exhibition, emergency, entertainment, military, and space structures that require rapid deployment. It also can be used for shelters, roofs, bridges, pylons, radars, vaults and structures of various configurations.
Number | Date | Country | Kind |
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PCT/SG05/21882 | Sep 2004 | SG | national |