Deployable Structures : Collapsible Structure from a Rulled Surface

DEPLOYABLE STRUCTURES Collapsible Structure from a ruled surface

DEPLOYABLE STRUCTURES : Collapsible Structure from a ruled surface A Dissertation submitted for (MArch) Master of ARCHITECTURE RIBA PART II

By Margarita Vervele Canterbury School of Architecture Tutor: John Bell

CONTENTS

Introduction............................................

7

Making the “ring” & the “legs”................ 50

Significance of deployable structures.... 10

Final Model............................................ 52

Concepts of deployable structures........ 12

Conclusion............................................. 67

Hoberman’s deployable structure.......... 14

Bibliography........................................... 69

Scissors deployable structures.............. 16 NASA type cubic.................................... 18 Fast mast............................................... 20 Construction........................................... 22 Model 01................................................ 23 Model 02................................................ 25 Model 03................................................ 27 Model 04................................................ 35 Model 05................................................ 44

INTRODUCTION

TREE DIAGRAM

NASA TYPE CUBIC DEPLOYABLE BASED ON BENNET LINKAGES

Deployable Typologies

LATTICEWORK

TWO-WAY-FOLD TRUSSES

ROLLING BRIDGE

SCISSORS RADIAL EXPANSION/RETRACTION

RIGID-FOLDABLE THICK ORIGAMI

TRUSS STRUCTURE

RIGID ORIGAMI STRUCTURES WITH VACUUMATICS

ORIGAMI PAPER PLEAT

COMPOSITE RIGIDFOLDABLE CURVED ORIGAMI STRUCTURE

GENERATIVE TECHNIQUE

RIGID CENTRIFUGAL ANTENNA

SOLID SURFACE

DEPLOYABLE HINGED PLATES DEPLOYABLE ‘BLOB’ STRUCTURES

RIGID ORIGAMI BAG

PUSH BUTTON HOUSE 1

DEPLOYABLE TYPOLOGIES

WING FOLDING IN BEETLES THE GEOMETRY OF UNFOLDING TREE LEAVES

ANIMALS

NETS FABRICS INFLATABLES

PLANTS BIOMIMETICS STRUCTURAL COMPONENTS

ELASTIC KINEMATICS CONCEPTS FOR ADAPTIVE SHADING SYSTEMS

DEFORMABLE

FLEXIBLE

BENGT SJOSTROM STARLIGHT THEATRE

TENNIS COURT ENCLOSURE INFLATABLE AIR CELL STRUCTURES COMMONWEALTH AEROSTAT

STEMS FAST MAST

COMBINED

THREE-DIMENSIONAL DEPLOYABLE SCISSOR GRIDS DEPLOYABLE COVER FOR SAN PABLO SWIMMING POOL RETRACTABLE MEMBRANE SOUNDSFORMS SARA

FOUR-STAGE MAST EIGHT-STAGE MAST

Sourced from Adrover, E. R., 2015. Deployable Structures (Form + Technique)/ redrawn

AXI-SYMMETRIC REFLECTOR ANTENNA

With so many technological changes, there has been a significant change in archi-

figure of an example to show how deployable architecture works:

tectural designs too. With newer and advanced technologies, nowadays, deployable structures are prepared that can turn into a specific structure and can re- fold or return to normal shape for ease of accommodation. In order to explain what a deployable structure is, it is important to consider that it is a kind of structure that changes shape and correspondingly changes size as well.

However, this concept of deployable structures is not a new one and all the human beings have known such deployable structures for years or probably from the time they were able to comprehend. Examples of the basic or very common deployaFigure 1: Deployable house (Weebly, 2015)

ble structures include umbrellas. Other than this, bi- stable structures, tensegrity structures, scissor like structures as well as some of the Origami shapes too are

This research helps to identify that deployable structures can be a beneficial

considered as deployable structures. Despite the fact that these all does not fall in

use as well as very important and prospective technology for the architectural

the category of architecture; but it is important to consider that these are the basic

industry. In order to discuss deployable architectural technology and structures,

deployable structures one could consider for understanding.

this paper will be sub- divided into different sections. The first section, after

Another very useful and interesting example of deployable structures can

introduction, will be about significance of deployable structures. In this section,

be seen in spacecraft where solar panels and solar cells are deployed. The pro-

importance or benefits of deployable structures with respect to their character-

cess through which solar panels and cells are deployed in a spacecraft includes

istics will be discussed. Followed by this, some of the basic concepts used in

deployable structures.

deployable structures will be discussed briefly as well.

Deployable structures categorized for space crafts and other machines

Also, benefits of folding and development of such transformable struc-

are basically categorized into 3 primary categories; where the 1st category is of

tures will be highlighted. Along with this, some of the different deployable struc-

articulated structure (in this category, structures slide on contact joints or fold on

tures as the architectural technology will be discussed such as the Hoberman’s

hinge/ pivot joints; however, this helps in locking of structure too) (Adrover, 2015).

structures and scissors like structures. Furthermore, different deployable struc-

The second category is of on- orbit structures where device or structure is me-

tures such as NASA type cubic and fast mast will also be discussed. Lastly, I will

chanically joined/ developed in space. Lastly, the third category of space based

describe how I developed my own deployable structure from a ruled surface. At

deployable structures is high strain structures where the structure is developed

the end a conclusion will be included that will provide summary of findings from

such that it flexes between one configuration and another easily. Following is a

this research.

9

01

SIGNIFICANCE OF DEPLOYABLE STRUCTURES

In this fast paced world with so many technological advancements, it should not

Figure 2: Hoberman Geodesic Domes (Hoberman, 2011)

be neglected that people migrate or change their locations with respect to feasibility for employment opportunity as well as for other reasons too. For this purpose, architectural designs and structures are quite beneficial since they help the owner to move around easily. Folding and transformation helps the owner of product to change its form whenever in need. Along with this, folding also helps the user to change the purpose of plain sheet of paper for which it may be used.

Moreover, with the help of unfolding the same folded or transformed structure, it is clearly identified that how the structure was developed; in this way, it can be replicated multiple times as well as on different scales. A morphogenetic solution can be employed through folding a system or design that can be made on a sheet of paper. This sheet of paper, then, can be folded and transformed into inhabitable structure. Along with this, since the structure is folding and transformable, cost efficiency and ease of fabrication will be reduced; this in turn will help to design systems or structures that can be built through low cost materials. These structures, thus, can be used for development of accommodations aesthetically and programmatically.

In light of this immense benefit that deployable architecture can provide, it is important to note that deployable architecture and structures can be easily used and provided as a means of accommodation facility in areas that have been hit by tsunamis and earth quakes. With the help of deployable and transformable structures, a transitional shelter may be provided to devastated communities in time of crisis management. In this way, deployable architecture can be a means of shelter for people who have lost their belongings due to natural disasters and other calamities.

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02

CONCEPTS OF DEPLOYABLE STRUCTURES

Deployable structures are based on three basic concepts. Of the three concepts,

In doing so, continuous analysis and review, errors that are usually left

two are genetic and new ones that are based on foldable cylinders and solid sur-

out previously are removed and new fold pattern is generated that is error free.

face deployable reflector. On the other hand, the third concept is an old one where

Also, with the help of this step, different ways are suggested that shows how a

a membrane, extended after analysis, is folded. According to the new concepts

concept could be extended further on. Another example of deployable structure

of deployable structures, foldable cylinders can transform into a stack of plates

is a solid surface deployable antenna. With the help of this antenna and its new

and are triangulated in shape. These cylinders fold in axially and transform into a

method of folding, a new wrapping method or fold pattern is identified.

compact structure.

Moreover, this antenna and its new folding method helped to understand

In the concept of foldable cylinders, a geometric approach is also intro-

that size can be considerably reduced in case of folding and there is no further

duced that provides insights about how the structure can be folded easily. On the

complex mechanical components required to do so. A new technique is usual-

other hand, folding is also analysed and computed to know how the experiments

ly implied in antenna’s model where rigid body displacements are represented

are taken of or what behaviour is shown by the structure. It has been identified that

through dual quaternions. The same design of antenna can further be optimized in

numerous cylinders have developed and experimented. The very first one was

order to remove any sort of deformation. The following figure shows a deployable

developed by wrapping a membrane around a central hub in 1960’s. However,

antenna:

sometime ago, this process has been considered to be a folding process of a space sail. With continuous conceptual analysis and review, new folding patterns are generated easily. The following figure shows a foldable cylinder:

Figure 3: Deployable cylinders (University-of-Surrey, 2016)

Figure 4: Deployable antenna (JAEA, 2008)

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03

HOBERMAN’S DEPLOYABLE STRUCTURE

First of all, to understand what Hoberman’s deployable structures are, it is im-

A number of exhibitions have been conducted that exhibited work of Hoberman

portant to note that Hoberman is a founder of Hoberman Associates. Hoberman

and its associates such as the one which was held in the Museum of Modern Art

associates is well known for the production of various products such as deploya-

in New York. One of the commissioned installation of Hoberman’s associates,

ble shelters, consumer products, as well as some space structures. A well- known

known as Emergent Surface, was also exhibited in the ‘Design and the Elastic

example of Hoberman’s structures include a transformable LED Screen used for

Mind’.

the U2 360 degrees world tour as a primary stage element (James, 2008). Along

Conversely, there have been so many developments and a number of structures

with this. Hoberman’s Arch in Salt Lake City was installed for the Winter Olympic

have been developed by Hoberman’s associates. According to Chuck Hoberman,

Games as a centerpiece. Following is the figure of Hoberman’s Arch:

unfolding architecture can be defined as an object that can be considered as an identical mechanism as well as structure. He also emphasized that such innovations could help in transfer of forces and motion in a controlled manner, where any secondary support systems will not be required.

Furthermore, Hoberman also posits that development of structures

through repetitive pleating of single sheet can help to transform between two states of a deployable structure; active state and dormant state. The active state refers to the structural configuration for which it has been developed and the dormant state refers to one that is a compact bundle. The system developed acts as a mechanism, developed through different matrix of fold, and allow such surface structures to behave like some kind of rigid and hinged plates.

Figure 5: Hoberman’s Arch (W, 2016)

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04

SCISSORS DEPLOYABLE STRUCTURES

With the increased need of light weight and kinetic structures, scissors like structure found a way into deployable architecture. A good example of scissors structure is the Hoberman’s sphere, an isokinetic structure. The structure is much like the geodesic dome that can fold and become a fraction of its normal size. This is accomplished with the help of joint’s action that act like scissors. The same structure is also available for children in colourful plastics where different sizes of the sphere can be seen. The actual design developed by Hoberman and associates can expand to a range of 15 centimetres, which is approximately 5.9 inches, in diameter and over as well to 30 inches or 76 centimetres (Pellegrino & Guest, 2000).

Deployable architecture based on scissors action are of great interest.

The Hoberman sphere is made up of six large circles. Each of the circle corresponds to an edge of icosidodecahedron. The sphere can easily unfold and fold with the help of certain members that fold and unfold. This is usually accomplished through the use of cable that are fed out in larger models. To date, the largest

Figure 6 : Hoberman’s sphere is AHHA Science Center (Hoberman, 2011)

sphere is located in the AHHA Science Center situated in Estonia (Tartu). The fully expanded sphere is about 5.9 meters in diameter or 19 ft. wide. The sphere weighs around three hundred and forty kilograms and is suspended above the Center’s Science Court. The sphere is constructed with aircraft grade aluminium.

The sphere changes between the two states, collapsed and expanded, constantly through a control system along with lighting, music and some special effects. Following is a figure that shows the Hoberman’s sphere is AHHA Science Center:

17

05

NASA TYPE CUBIC

For the development of NASA type cubic deployable structure, the developers considered symmetry as a basis for geometrical and morphological development.

Different types of NASA type cubic deployable structures have been developed; namely, NASA PACTRUSS, X- BEAM and the STAC- BEAM. As per the structure of NASA PACTRUSS, it was seen that it is a lightweight structure. This structure was particularly used in different deployable structures such as deployable reflectors and antenna (Britt & Lalvani, 2014).

On the other hand, X- BEAM and STAC- BEAM, both, are considered

to be beneficial for as extendable support structures. These support structures are used to support platforms of solar concentrators and phased arrays. The researchers while working on the development of NASA type cubic deployable structures found that slight changes in the geometrical arrangements of STACBEAM can result in the formation of new structure, which is geometrically like the original piece but shows some different geometry in deployment. Following in a figure of NASA type cubic deployable structures where different shapes or possible geometrical arrangements are shown:

Figure 7 : NASA type cubic deployable structure (Britt & Lalvani, 2014)

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06

FAST MAST

Ever since the developments of deployable technology is the field of architecture, there has been an increased need to reduce weight of the structures. For this purpose, different experiments have been conducted and it has been found that extra bracing members can do the job and thus should be added in the structure. Along with this, the constraints added by bracing members can help to figure out different facts about deployable structures. To understand this scenario, a deployable structure developed by AEC- able Engineering in California known as the Folding Articulated Square Truss Mast (FAST Mast) can be considered (Pellegrino, 2014).

This structure of FAST Mast includes square frames that have hinge

axes directly parallel to them. Along with this, two pairs of cross bracing cables are also places on each face of the cube. It should be noted that half of the cables become limped while the structure folds and on the other hand, all the slacks and cables are taut when the structure is in complete open or deployed form. The following figure shows how the FAST Mast is expanded or collapsed and how cables as well as hinge axes help in doing so (in the transition phase) (Pellegrino, 2014):

Figure 8: Figure: Fast Mast (Pellegrino, 2014)

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07

CONSTRUCTION DEPLOYABLE STRUCTURES: COLLAPSIBLE STRUCTURE FROM A RULLED SURFACE • • • • • • •

Model Development 01 Model Development 02 Model Development 03 Model Development 04 Model Development 05 Making the ring & the “legs” Final Model

07

.1

MODEL DEVELOPMENT 01

ERROR

The pivot point of the connection should be horizontal and facing the “ring� structure.

The model was made by 2mm MDF and I have used 4mm nuts and bolts for the connections.

24

07

.2

MODEL DEVELOPMENT 02

ERROR

The structure bends too much.

I have used 1mm thin card and 4mm nuts and bolts for the connections.

26

07

.3

MODEL DEVELOPMENT 03

ERROR

The openings are very close to the edge and the structure is too thin.

I used 2mm grey card and 2mm nuts and bolts for the connections.

28

07

.4

MODEL DEVELOPMENT 04

ERROR

All the “X� scissors - like connections have been brought forward, and there are cracks on the structure.

I used 2mm grey card and 2mm nuts and bolts for the connections.

36

07

.5

MODEL DEVELOPMENT 05

ERROR

The length of the “ring� components should be the same with the The components of the model

vertical scissors - like components.

I used 2mm grey card and 2mm nuts and bolts for the connections.

I have 3D printed the connection components.

45

07

.6

MAKING THE RING & THE “LEGS”

ERROR

The structure bends too much and breaks under pressure.

•

To stop it from breaking, I have added extra material near the edges.

•

At the end, I found that connecting the legs with the ring, it won”t work.

51

07

.7

FINAL MODEL

Making the scissors - like components

57

The 3D printed hinges connect all the scissors - like components together and help the structure to fold and unfold.

Why six sides? We know from Origami paper making that the folds have to be an even number so the structure can be folded and unfolded a lot faster.

To put together the hinges, I have used 1.8 mm copper rod. From the 1 meter long copper rod I cut pieces with length 45 mm. After inserted the copper rod into the hinge’s hole, I trimmed and bended the edges using pliers.

•

All the scissors- like elements have been laser-cut using 3mm black acrylic.

•

For All the connections, I have used 2mm nuts and bolts.

•

To put together the hinges, I have used 1.8 mm copper rod.

58

Folding the scissors components

59

The scissors components

3D printed Hinges Laser cut Black Acrylic

Laser cut Black Acrylic

Laser cut Black Acrylic - Acting as a washer

60

The scissors components

scale 1:1

61

The “feet” of the structure scale 1:1

The “feet” hold together the scissors - like components and help the structure to stand up.

62

The “head” of the structure scale 1:1

The “head” holds together the acrylic struts. Under load pressure the cables going through the little ball like system (under the head while they are connected to the part of the bottom “legs”) will make the whole structure more stable. I used super glue to glue the 2 separate pieces.

63

The “strut connectors� scale 1:1

The 3D printed components hold the struts. The struts are made from black acrylic. I used super glue to glue the 2 separate pieces.

65

Final Model with cables

This structure is self-supported but it can be load-bearing - holding lightweight structures by attaching cables to the top and bottom part.

The structure is stabilized into the deployed state by attaching the cables to the pivot point under the “head�. Under load pressure the compressive forces are resisted by the top struts while the tensile forces are resisted by the cables at the bottom of the structure and the shear forces are resisted by the scissors -like components.

The cables are fishing wire with 0.45 mm thickness.

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08

CONCLUSION

In conclusion, it can be stated that the deployable technology in architectural

Deployable structures are easily foldable and transformable, thus, provides cost

industry has opened ways to modern developments, which can help in several

efficiency and ease of fabrication; this in turn, such structures help to design

ways. A number of factors to be considered here include that deployable

systems or structures that can be built through low cost materials. This is why

architecture helps to reduce size as well cost effectively. This is so because

it is said that deployable structures can be used to reduce expenditure too. De-

deployable structures are foldable and can reduce to bigger or smaller sizes.

ployable structures, thus, can be used for the development of accommodations

This helps in easy accommodation too.

aesthetically and programmatically.

It is also important to note that deployable architecture and structures can be

In this paper, it was identified that deployable structure is a kind of

structure that changes shape and correspondingly changes size as well. Deploy-

easily used and provided as a means of accommodation facility in areas that

able structures categorized for space crafts and others are basically categorized

have been hit by tsunamis and earth quakes. A transitional shelter may be

into 3 primary categories; where the 1st category is of articulated structure. The

provided to devastated communities in time of crisis management. Furthermore

second category is of on- orbit structures where device or structure is mechan-

continuous analysis and review, errors that are usually left out, previously, can

ically joined/ developed in space. Lastly, the third category of space based

be removed and new fold pattern can be generated that is error free. Also, with

deployable structures identified was of high strain structures.

the help of this step, different ways are suggested that show how a concept

Architectural designs and structures are quite beneficial since they

could be extended further on. Another example of deployable structure identified

help the owner to move around easily. In this paper, it was also identified that

in this paper is a solid surface deployable antenna. This research and construc-

folding and transformation helps the owner of a product to change its form when-

tion is beneficial for the understanding of deployable structures that can change

ever in need. For example, there are now such wooden or iron tables that can

the outlook of architecture in near future.

change shape and transform into smaller or bigger sizes depending upon the need of owner or user. Along with this, folding also helps the user to change the purpose of plain sheet of paper for which it may be used. Plain sheet of paper is usually used here in the context that deployable structures are made such that they resemble a plain sheet of paper and thus facilitates accommodation easily.

68

09

BIBLIOGRAPHY

Adrover, E. R., 2015. Deployable Structures (Form + Technique). s.l.:Paperback.

Britt, A. L. & Lalvani, H., 2014. Symmetry as a Basis for Morphological Analysis and Generation of NASA-Type Cubic Deployables. s.l.:Springer .

Hoberman, 2011. Expanding Sphere (Estonia). [Online] Available at: http://www.hoberman.com/portfolio/sphere-estonia.php?&projectname=Expanding+Sphere+(Estonia) [Accessed 28 February 2016].

Jackson, Paul., 2011. Folding techniques for designers: from sheet to form.

JAEA, 2008. HALCA. [Online] Available at: http://www.isas.jaxa.jp/e/enterp/missions/halca/ [Accessed 28 February 2016].

James, A. M., 2008. Deployable Architecture , s.l.: Georgia Institute of Technology.

Pellegrino, S., 2014. Deployable Structures. s.l.:Springer.

Pellegrino, S. & Guest, S. D., 2000. Solid Mechanics and Its Applications. s.l.:Springer .

Pellegrino, S. & Guest, S. D., 2013. IUTAM-IASS Symposium on Deployable Structures: Theory and Applications: Proceedings of the IUTAM Symposium held in Cambridge, U.K., 6–9 September 1998. s.l.:Springer Science & Business Media.

University-of-Surrey, 2016. FOLDING INFLATABLE STRUCTURES. [Online] Available at: http://www.surrey.ac.uk/ssc/research/space_vehicle_control/deploytech/science_and_tech/folding_inflatable_structures/ [Accessed 28 February 2016].

W, 2016. Welcome to Waymarking.com!. [Online] Available at: http://www.waymarking.com/waymarks/WMJ70X_Hoberman_Arch_Salt_Lake_City_UT [Accessed 28 February 2016].

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Weebly, 2015. Zsombor Nagy. [Online] Available at: http://zsombornagy.weebly.com/deployable-architecture.html [Accessed 28 February 2016].

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