EP2951363B1

EP2951363B1 - Pre-assembled display structure

Info

Publication number: EP2951363B1
Application number: EP13815112.1A
Authority: EP
Inventors: Aikaterini LIAPI; Christianna ANAGNOSTOPOULOU
Original assignee: University of Patras
Current assignee: University of Patras
Priority date: 2012-12-05
Filing date: 2013-12-05
Publication date: 2018-03-14
Anticipated expiration: 2033-12-05
Also published as: WO2014087178A2; WO2014087178A3; GR20120100608A; GR1008904B; EP2951363A2

Description

Technical field

The invention belongs to a class of structures named "tensegrity" and it uses the general features and properties of these structures.

Prior art

Tensegrity structures comprise a) compression members that do not come in contact with one another and b) tension elements that form a closed network.
Such structures are described by Fuller R.B., in "Tensile-integrity structures", US Pat. 3,063,521, November 13, 1962 , by Emmerich D.G., in French Patent No 1,377,290, 1964 and by Snelson K.D., "Continuous tension, discontinuous compression structures", US Pat. 3,169,611, February 16, 1965 , Katherine A. Liapi (2005) US Pat. 6,901,714 , "Tensegrity Unit, Structure and Method for Construction".
Tensegrity structures are known to be self-supported and self-tensioned and as such they do not require heavy foundations. Patent document US3901551 comprises all the features of the preamble of claim 1.
Since the connections between tension elements and compression elements are usually very simple and do not transfer any moments, tensegrity structures may be deployable, as described by the prior art publications mentioned above and also by Hanaor, A. in "Tensegrity theory and application". in J. Francois Gabriel (ed.), "Beyond the Cube", New York: John Wiley & Sons, Inc., 385-408.
Applications of the tensegrity concept are encountered in space, in marine and in building or recreational structures and such applications include space antennas, floating fishing platforms, surface structures for purposes of covering spaces and camping tents.
However, further from tensegrity camping tents that enclose habitable space, there is a need for tensegrity structures that are able to enclose space that will serve totally different needs and functions.
Specifically, there is a need for structures that will enable the display of objects or products in closed or open-air spaces such as expo-building, closed market buildings, fairs, open markets etc. Such structures require special features and performance such as short assembly and short erection time, easy assembly and easy disassembly, possibility for the structure to be re-used more times, low cost etc.
Currently, structures that serve relative and similar needs are always assembled on site, where they will be used. Assembling on-site is typically a less efficient process than pre-assembly, as it usually requires more time, and/or specialized man-power and therefore it is more expensive in labor costs. Additionally, assembling on-site typically requires individualized design and construction processes that are usually costly and often do not lend themselves to easy reassembly or re-use of the structure.
Until today there are not known in the art any "off-the-shelf" structures, that enclose space and may be used for traveling exhibitions, temporary commercial activities and other similar uses (functions) which require temporary display of objects or products and which structures may be repeatedly used at different times and at different places without limitations.
The present invention solves this problem in that it describes for the first time a structure that is portable and deployable and can be lightweight, with low construction and low maintenance cost.
The structure described in the present invention uses the general features and properties of tensegrity structures. The structure of the present invention is a self-tensioned, self-supported structure with simple connections between tension and compression members, it is portable and deployable and it can be lightweight with low construction and low maintenance cost.
The structure of the invention is ergonomic and fulfills the functionality requirements that are necessary for the intended use in a way that is much better and much more efficient than any known structure today.

Summary of the invention

The tensegrity structure described in the present invention is deployable and encloses space. This structure is formed of compression members, hereinafter referred to as rods and of tension members, hereinafter referred to as cables.
Optionally, one of the advantages of the structure of the present invention is that a tensioned membrane can be used to fully or partially cover the structure.
The structure is symmetrical in one axis in plan and encloses at least one sub-space and preferably two sub-spaces that differ in height and volume.
The structure is lightweight and its construction and maintenance costs can be kept very low. Very short time is needed for the deployment, erection and collapse of the structure with manpower kept at a minimum, with a maximum of two people needed and with no need for specialized tools.
When the structure is in a non-deployed state, namely when it is in a collapsed state, the compression members (the rods) may be easily positioned in a compact bundle, while the tension members (the cables) may remain coupled to compression members so that there are no loose tension member ends that may otherwise become tangled. In a non-deployed, namely in a collapsed state, the structure can be easily transported in a vehicle.
In the deployed state, more than one space-enclosing tensegrity structures as described in the present invention may be placed next to each other to form linear, radial or other multi-unit structures.
No other tensegrity configuration is reported in literature that has similar spatial features as described in the present invention and that is also deployable.
While it is well suited even for permanent structures, the possibility of easy transfer, portability and rapid deployment of the structure of the present invention renders it appropriate for temporary or travelling exhibitions, for vending activities in recreational areas, fairs, open markets etc.
The invention can be also used as the basic unit structure to equip exhibition halls and closed markets.
Also, while for general purposes the cost of the structure can be kept low, for exhibition purposes more elaborate material and joints may be used.

Figures

The invention is illustrated by the Figures 1 to 3.

Figure 1 shows the structure in the deployed configuration with a covering membrane attached to it.
Figure 2 shows an arrangement of several tensegrity unit structures as in the invention in a formation where the one is next to the other.
Figure 3.1 shows the inside of a perspective view of the structure of the invention and
Figure 3.2 shows a plan view of the structure showing the rods and the cables without a covering membrane.

Detailed description of Figures and of a preferred embodiment

The structure described by the present invention is illustrated by mention of the above Figures. The structure comprises five rods (compression elements) shown with numbers 1, 2, 3, 4, 5, that do not come in contact with one another, they are connected with cables (tension elements) a, b, c, d. e, f, g, wherein the cables transfer axial forces. The bottom, or lower, distal ends of the four rods 1,2,3,4 are at the same level, are coplanar and form the base of the structure. The bottom, or lower, distal ends of two of the rods (3, 4) form the front of the base of the structure when this is seen by a viewer and these are referred to herein as the front supporting rods of the structure. The other two rods (1, 2) whose bottom, or lower, distal ends form the back of the base of the structure when seen by a viewer, are referred to hereinafter as the two "back" supporting rods (compression elements) (1, 2) of the structure. A fifth rod (compression element) (5) is in horizontal position, parallel to the base plane of the structure.
The said structure encloses usable space, it is symmetrical to a symmetry plane perpendicular to the horizontal rod (compression element) (5). Hence in the present description the structure has a right side which comprises the front rod (compression element) (4) and the back rod (compression element) (2) of the right part of the structure, when seen by the viewer and these are hereinafter referred to as the "front right compression element (rod) (4) and the "back right" compression element (rod) (2) respectively and their symmetrical rods on the left part of the structure, when seen by the viewer, are hereinafter referred to as the "front left" compression element (rod) (3) and the "back left" compression element (rod) (1). The said structure is collapsible, namely it is deployable.
Preferably, in the structure of this invention, the tension elements can be cables, wire cables or ropes.
Further, it is advantageous, that in the structure of the present invention the bottom, or lower, distal ends of the two front compression elements (rods) (3) and (4) of the structure are connected with one another with a tension element, (hereinafter referred to also as cable) (a), which is placed parallel to the base plane and in contact with the ground, while the upper distal ends of the two front compression elements (rods) (3 and 4) of the structure are connected with one another with a tension element (cable) (b), which is also parallel to the base level.
Similarly, the lower (bottom) distal ends of the two back rods (1 and 2) of the structure are connected with one another with a tension element (d) placed parallel to the base plane and the upper distal ends of the two back rods (1, 2) of the structure are connected with one another with a tension element (c) parallel to the base plane.
Each one of the distal ends of the horizontal compression element (rod) (5) is connected with tension elements (e) with the upper and the bottom distal ends of the respective adjacent supporting rods; in the embodiment described here the right distal end of the horizontal rod (5), when seen by the viewer of the structure, is connected with tension elements (e) to the upper and bottom distal ends of the right front rod (4) and to the upper and bottom distal ends of the right back rod (2) and the other distal end of the horizontal rod (5), namely the left one when seen by the viewer of the structure, is connected with tension elements (e) to the upper and bottom distal ends of the left front rod (3) and to the upper and bottom distal ends of the left back rod (1).
The upper distal end of the left front compression element (rod) (3) is connected with continuous tension elements (f) with: i) the upper distal end of the left back compression element (rod) (1) and ii) the bottom distal end of the same left back rod (1). Also, the upper distal end of the right front rod (4) is connected with continuous tension elements (f) with: i) the upper distal end of the right back compression element (rod) (2) and ii) the bottom distal end of the same right back rod (2).
The bottom distal end of each one of the back rods (1,2) is connected with a continuous tension element (g) with the bottom distal end of each one of the front rods (3,4) that is on the same side as seen by the viewer. The same bottom distal end of each one of the front compression elements (rods) (3,4) is connected with a continuous tension element (g) with the middle point of the same back compression element (rod) (1,2); namely

the bottom distal end of back compression element (rod) (1) is connected with a continuous tension element (g) with the bottom distal end of front compression element (rod) (3) and the said bottom distal end of front rod (3) is connected with another continuous tension element (g) with the middle point of compression element (rod) (1) and
the bottom distal end of back compression element (rod) (2) is connected with a continuous tension element (g) with the bottom distal end of front compression element (4) and the said bottom distal end of front compression element (rod) (4) is connected with another continuous tension element (g) with the middle point of back compression element (rod) (2).

In the structure of this invention the rod (5) which is parallel to the base plane of the construction is retractable.
Advantageously, in the structure of the invention, the compression elements can be rods or bars and can be made of metal, wood, plastic, synthetic or any other material that is able to undertake compression forces.
Preferably, the structure of this invention may be covered by a surface element, or membrane, which surface element or membrane is either placed after the erection or the deployment of the structure, or it is pre-attached at the ends of the members of the structure. The coverage with this surface element or membrane may be partial or full.
The structure of the invention comprises base-support elements, that can be adjusted to withstand external loading conditions. i.e. wind etc. A base-support elements comprises:

a) a case that comprises four surfaces preferably made of steel, or other material similar properties and strength, where these surfaces form the four continous side surfaces of a parallelepiped. This parallelepiped is positioned on the ground on its biggest side surface, while the other two facing sides of which remain uncovered,
b) slabs, preferably made out of lead or other materiall with similar properties and weight, with their largest dimension matching the dimensions of the side surface of the case that is situated on the ground, and which stabs can slide and fit into the box and sit one over the other. By adjusting the number of lead slabs inside the case, the weight of the base-support element can be adjusted to withstand external loading conditions such as wind loads and thuis, remain in place.

In the structure as described in the present a display tray (6) can be attached on the horizontal rod (5). The tray may also be suspended by the side rods (1,3 and 2,4). This invention also includes a method of collapsing (disassembling) the structure of the invention, wherein the tension elements (cables) (a, b, c, d. e, f, g) are not disconnected from the distal ends of the rods but are loosened by a special/specific mechanism of the coupling; then the tension elements (e) which have been connected to the end of the horizontal compression element (rod) (5) are being removed along with the coupling which supports them, after the said rod has been retracted. At a following stage, the continuous tension elements (g) that are connected to the distal ends or the middle point of each of the four supporting rods (1,2,3,4) are first loosened with the use of a mechanism, and then are removed by a special formation of the coupling that holds them to the other rod, letting, in this way, the four supporting rods (1,2,3,4) to be positioned parallel to each other to form a bundle that can be easily transported in a vehicle.
Preferably more than one of the structures of this invention can be used in various formations, i.e. the one next to the other, linear, radial etc.
The structure of the invention can be used for the exhibition or various objects, or the display of products. It can be placed in an interior, like in the case for an exhibition hall, a closed marked building or it can also be placed in an exterior space, as in an open exhibition or market space.
It is advantageous that the structure of the invention includes sub-spaces for the exhibitor or vendor and for the viewer or buyer and an adjustable tray (6) to address various object or product display requirements. Ergonomic parameters have been utilized to determine the overall dimensions of the structure including the functional space for the viewers or buyers and the exhibitors or vendors.
Several unit structures can be placed back to back or one next to the other to form a larger compound of structures to serve the needs of a larger number of exhibitors or vendors. Linear, radial and other organizations of unit structures as described in the present invention are possible.
The covering surface can fully or partially cover the structure. Depending on the exhibitor's or vendor's needs, a storage space behind the exhibitor or vendor can be created with the appropriate use of the membrane-fabric. The membrane can be of fabric or of any other material whose properties resemble the preperties of fabric, i.e. it may be made of composite or syntheric fabric.
If the structure is to be placed in an exterior space, the environmental loads, ie. from wind, rain or snow, need to be taken into account for the selection of the material and the dimensioning of the cross section of the basic elements of the structure.
The structure of the invention is composed of simple material such as wire cable for the tension elements and metal or aluminum tubular bars or rods for the compression elements. Preferably the cover is made of flexible membrane. For the joints, commercially available hardware and some shop machining will be needed. The size and scale of the structure can be slightly modified, yet basic ergonomic dimensions and proportions need to be kept.
The exhibitor or vendor can deploy and erect or collapse the structure in a very short time with manpower at a minimum, maximum two persons and no specialized tools.

Claims

A structure that comprises
- five compression elements (1,2,3,4,5) which
- do not come in contact with one another,

- are connected with tension members (a, b, c, d, e, f, g),

- the tension members (a, b, c, d, e, f, g) transfer axial forces,

- the bottom distal ends of four compression elements (1,2,3,4,) are coplanar and form the base of the structure, wherein the bottom distal ends of compression elements (3,4) form the front of the base of the structure and the bottom distal ends of compression elements (1, 2) form the back of the base of the structure,

- the fifth compression element (5) is in a horizontal position, parallel to the base plane of the structure,

- which structure
- encloses usable space,

- is symmetrical to a plane perpendicular to the horizontal compression element (5),

- has a right side that comprises the front right compression element (4) and the back right compression element (2) and a left side that comprises the front left compression element (3) and the back left compression element (1),

- the structure is collapsible,
wherein
- the bottom distal ends of the two front compression elements of the structure (3,4), are connected with one another with a tension member (a) which is placed parallel to the base plane and in contact with the ground,

- the upper distal ends of the two front compression elements of the structure are connected with one another with a tension member (b) which is parallel to the base level,

- the upper distal ends of the two back compression elements (1 ,2) of the structure are connected with one another with a tension member (c) placed parallel to the base plane,

- the upper distal end of each one of the front compression elements (3,4) is connected with continuous tension members (f) with the upper distal end of the back compression element (1,2) of the respective side and - the bottom distal end of each one of the back compression elements (1 ,2) is connected with continuous tension members (g) with the bottom distal end of each one of the front compression elements (3,4) that is on the same side,

the structure being characterized in that,
- the bottom distal ends of the two back compression elements (1, 2) of the structure are connected with one another with a tension member (d) placed parallel to the base plane,

- each one of the distal ends of the horizontal compression element (5) is connected with tension members (e) with the upper and the bottom ends of the respective adjacent supporting compression elements (1, 2, 3, 4),

- the upper distal end of each one of the front compression elements (3, 4) is connected with continuous tension members (f) with the bottom distal end of the back compression element (1, 2) of the respective side, and

- the said bottom distal end of each one of the front compression elements (3,4) is connected with a continuous tension member (g) with the middle point of the back compression element (1 ,2) that is on the same side, namely the bottom distal end of the front compression element (3) is connected with the middle point of the back compression element (1) and the bottom distal end of the front compression element (4) is connected with the middle point of the back compression element (2).
A structure according to claim 1wherein the horizontal compression element (5) is retractable.
A structure according to claim 1 or 2, wherein the tension members are cables, wire-cables, or ropes.
A structure according to any one of claims 1 to 3, wherein the compression elements are rods or bars that are made of metal, wood, plastic, synthetic, or any other material that is able to undertake compression forces.
A structure according to any one of claims 1 to 4, wherein said structure is covered, fully or partially, by a surface element, which is either placed after the erection of the structure, or is pre-attached at the distal ends of the members of the structure.
A structure according to claim 5, wherein the surface element is a flexible or inflexible composite or synthetic material.
A structure according to any one of claims 1 to 6 comprising a base support element,
wherein said base support element comprises
- a case that comprises of four surfaces, wherein the four surfaces form the four continuous side surfaces of a parallelepiped that is positioned on the ground on its biggest side surface, two of the four surfaces are made of steel, or other material with the same properties and the other two facing sides of the case remain uncovered;

- slabs, made out of lead or of other material with similar properties and weight, wherein
the largest dimensions match the dimensions of the side surface of the case that is situated on the ground,

they can slide and fit into the case and sit one over the other, adjustement of the number of lead slabs inside the case, may adjust the weight of the base-support element to withstand external loading conditions such as wind loads.
A structure according to any one of the claims 1 to 7, wherein a display tray (6) is attached on the horizontal compression element (5) and where the display tray (6) is suspended by the side compression elements (1,2,3,4).
A plurality of structures according to any one of the claims 1 to 8, wherein the structures are arranged in formation.