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Adaptable membrane , research about the performance of a double layered membrane structure
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MEMBRANE SPACES studio course AHO fall 2008
adaptable membrane double layered membransystem-controlable permeability
yü chen // professor in charge: michael hensel // additional staff: birger sevaldson and defne sunguroglu
AHO The oslo school of architecture and designm e m b r a n e spaces fall`08
adaptable membranemembrane spaces aho studio course fall 08professor in charge:michael henseladditional staff:birger sevaldsondafne sunguroğlu s t u d e n t s miray oktem liam rote-hahre yü chengroup project/individual project
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 2
ELASTIC MEMBRANE
PHYSICAL MODEL
DIGITAL MODEL
DIGITAL MODEL PROBLEM
DEVELOPING FROM FOR-MER PROJECTS
1. BASIC p04
2. LINKED MEMBRANESp05
3. PROPERTIESp.08
4. SYSTEM OF MEMBRA-NES p.09
5. CONTROLLING FALLING OBJECTS
p.09
6. BASIC EXPERIMENTp.10
7. FORMFINDINGp.16
STIFF MEMBRANE
CONTENT
MEMBRANE SPACES studio course AHO fall 2008
3
TwO LAYER
GEOMETRY
1:?MOTION
MOVEABLE SURFACE
CUTTING PATTERNRESEARCH
VISUAL PENETRATION
wIND FLOw
SHADOw ANALYSIES
SCALE
8.iNDIVIDUAL PROJECTAPPROACH
p.20
9.SHAPEp.22
10.RESARCHp.30
11.PERFORMANCEp.32
12.SPATIAL EXPLORATIONp.39
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 4
a
b
c
d
BASIC KNOwLEDGES ABOUT MEMBRANES
A membrane is in general a thin, synthetic or natural,material and it`s structer belongs to the group of Tension Structures.Def:Tension Structures are only loaded in tension, with no requierments to take compression or bending forces.
Behavior of slim/thin elements in diffe-rent force conditions aI tensionbI compressioncI bending
ADVANTAGES OF MEMBRANES:
- light- slim- structural efficiency- good performances in case of fire
DISADVANTAGES OF MEMBRA-NES:
The biggest problem of a memb-ran structure is it`s low resistance against aerodynamic excitation (wind fluttering).Solving this Problem leads to the basic shapes of a membran struc-ture.
4 methods to prevend membrane structures of fluttering:
aI application of massbI double, in transverse dirctons curved surfacescI application of tensiondI forming a convex and a con-carve surface and holding them in tension against each other
Kg
a. adding massb. double curvaturec. application of tensiond. convex and concarve surface
MEMBRANE SPACES studio course AHO fall 2008
5
THE TwO BASIC FORMS
The saddleshape and the cones-hapeare the most commonly used double curved surfaces to make a construction stiff. They are also minimalsurfaces, which means that the structure, completly loaded in tension, is working on it utmost efficiency.
To understand the characteristics of membranes we created a basic saddle and a basic cone shape (a). after this started to manipulate it to find the limits of the material, how much tension may be applied and in which directions, before it wrinkles.
In the next task, we were suppo-sed to create three interconnected
membranes to understand how it changes the tension in all the sys-tem and effects all the membranes
in the system when one of the cont-rol points in the system is chan-ged. (c) During this experiment,
we understood that manipulating a membrane by changing even
a single control point changes all the system. So it is hard to change the place of a control point without
getting any wrinkles
a. saddle shape
b. cone shape
c. membaren with 5 control points
d. enclosed membrane
e.moving of a membrane system
b
c d
ea
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 6
way of grapes in different size through a membrane sytem. frames of a videofilm.
top view
MEMBRANE SPACES studio course AHO fall 2008
7
After understanding basicly how membranes works, we decided on two ways to investigate more on membran properties. One was to look closer on the shape (see p.8), and the other was to learn more about its reaction to other object.This membrane system is deve-loped in order to catch a drop-ping object (in this case different grapes) and reflect them to another membrane and in this , influencing the fall of the objects.we suspended the membranes according to falling direction of the grapes from the former membrane.
Small grapes jumped through the hole onto the next membrane
Bigger grapes skiped the hole and jumped only twice between the membranes
Medium Grapes where hitting more edges and jumped more rendomly
Conclusion:The bouncing angle depends on the the size(mass of the object.Discovering that different sized grapes (or with different mass) would go different ways we thought about a system to asort objects.Since we dind*t had enough know-ledge about the parameters which influences the way of an object through oure system, we decided to do deeper investigation on the bouncing properties of a simple membrane. This leeds to the experimentseries on p.XX.
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 8
To learn more about membranes, we decided to work with them in a different way.By producing stiff membranes using a polyester and fiberglass, we created an antic-lastic non-elastic object with a minimal surface. we can preserve some properties of the membranes even if it does not work as a memb-rane anymore. we painted different shaped membranes with polyes-ter and we also put fiberglass to some of them to make it stronger. we tried this method on saddles, cones, barrels and even membrane systems with more than one mem-brane and minimal holes.
PE and hardener.
membrane painted with polyester
membrane coated with fiberglass-math and polyester
USING STIFF MINIMALSUR-FACES FOR A COMPRESSION STRUCTURE.
The membranes all kept their shapes very well. The one coated in fiberglass where extremly strong and rigid.Discovering this, we thought that it could be a way for finding material efficianed compressing structures, similar to buildings like Sagrada familia (gaudi).
The catenary is the theoretical shape of a hanging flexible chain or
cable when supported at its ends and acted upon by a uniform gravi-
tational force (its own weight) and in equilibrium. It is mathematicaly
seen also a minimalsurface. Turned upside down it shows the ideal
shape for an arch in almost pure compression while suppoting
it*s own weight without bending moments in the material.
Since a membrane in a full loaded tension shows similar properties,
(minimalsurface, equibilirium of forces) We wondered if a memb-rane shape used in the other way around could also show this ideal
performance loaded with the same amount of compresson forces as it`s counterpart in tension forces.
Also we were perfectly aware of the fact, that if it as we thought than certainly someone on the world
would already using this, we liked the idea of a membrane minimal
surface as a rigid object used as an compression structure. Thinking of saddleshaped stiff object we made
two design proposals.
MEMBRANE SPACES studio course AHO fall 2008
9
As we progreesed in the membra-ne-bounce research, we replicated a former model. we created a completely rendom layered cluster as an intend of prolonging the balls flight. after many experiments that conclude the cluster being very uncontrollable, it evolves into two other clusters. One enclosed and one vortex.
The enclosed cluster is an inter-connected set of equal size memb-ranes. when we drop the ball from above as we had done in all the models, it bounces horizontally as well as vertically.
we could easily see that the ball would bounce more randomly in this pre-selected and systema-tic cluster than in the randonly built one. In the vortex, there was another factor which became very clear; speed. when the ball entered the vortex shaped cluster, it accele-rated quickly and had random exits.
We tried to visualize the reflection path of a ball in ne of our memb-
rane systems. we took a series of photos while we dropped the ball
to see if we can record the path but it was not helpful, because of the coulers in the environment it was
too hard to see only the path of the ball.(d)
So we decided to use a fluoresant ball and record it with a video ca-
mera under blacklight.(c) Through testing and recording
results with video and photo, we chose to concentrate on one mem-
brane at a time.
The task was to create 12 or similar membrane patches that are con-nected ot each other with a system and harmony. Before starting this task, we wanted to choose our-selves an aim, in order to explore membranes from performance point of view. we wanted work on a membrane system which works as a reflection path and reflects objects in a certain way that we would be able to direct different objects in different paths according to their size, weight or speed. we talked over ways of doing that over sketches and then started building a membrane which would collect falling objects but not direct them. we thought of this as a way of understanding how membranes re-acts when objects ofdifferent sizes fall on them. we created 2 groups of 6 membranes that are intercon-nected and another half group and assumed that our system is end-less.
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 10
After trying to understand the reflection path created by different membrane systems, we decided to go back to basics to be able to understand them on a more primitive level, so that we would be able to build knowledge about them from the foundation. we decided to work with just one membrane and record all the different reactions that membrane gives to objects with a different weight, angle or speed. We recorded the reflection path of different situations to under-stand the basic principles of falling object-membrane relationships.The pictures above are reflection path illustrations of a ball dropped on a flat membrane. in each photo a certain property of the ball has been changed to understand the relationship between these proper-ties and the reflection paths.
we worked with two different size of balls, 3 different speeds (we used the distance the ball went on the dispenser before it hits the membrane to create different speeds) and the angle between the membrane and the ball.By recor-ding this data visually, we created a table of information that allows us to compare different situations and retrieve information on how we should use membranes to crea-te the reflection path we want to create.
three different angles (30,60, 90)three different starting points in each angle
two different sizes of balls
two membranes of different tensions
PROCEDURE SETTING UP THE EXPERI-MENT
RUNNING THE EXPERIMENT 5 TIMES EACH
CAPTURING wITH A VIDEO-CAM
TAKE SEVERAL FRAMES OF EACH EXPERI-MENT
MERGE THE FRAMES TO ONE PIC.
TRACE THE PATH IN A CAD PROGRAMM AND ANALYSE THE ANGLES
COMPARE THE IN-FORMATION GAI-NED FROM THE EXPERIMENTS
MEMBRANE SPACES studio course AHO fall 2008
Size/tight-ness
Loose Tight
90 60 30 90 60 30
Fast I
Big A II
Slow III
Fast I
II
Slow III
Almost the same table as on the former page but with the information of re-flecting angles in different conditions.
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 12
Loose - Tight
In a loose membrane, a dropping object bounces higher and with a bigger angle. However when
the membrane is tighter, the ball bounces less, with a steeper angle which sometimes creates multiple
bounces on the membrane. The only exception to that is the situa-tion where the falling angle of the
object is very low and the membra-ne is loose, then it does not bounce
on the membrane but rolls over it instead
AngleFalling angle of the object creates different bouncing patterns. when the angle is 30, it tends to jump out of the membrane directly due to the direction of force applied on the ob-ject. So it is hard to say if the angle has an effect on the ??? when the object is sent to the membrane with an angle of 90, it bounces higher as the power is applied in that parti-cular direction but when the angle is lower, it tends to keep going in that angle.
Slow - Fast
when the ball has a slower speed, it bounces higher but nearer. This causes the ball to stay on the mem-brane longer than the faster one.
Heavy - Light
Heavy object boun-ces higher than the lighter one. d
MEMBRANE SPACES studio course AHO fall 2008
13
suspender fixed
three different falling objects
two membranes of the same properties suspen-ded in an angle of 60 to each other
small ball big ball dummy for a human( ball with join-ted limbs)
Ball 1 - small
Ball 2 - big
Man dummy
Then we decided to narrow down the parameters and do another experiment to see the difference in reflection paths of a small ball, a bigger and heavier ball and a man dummy we created. we wanted to see if having more than one piece connected with joints would effect the fall of an object. The graph on the left shows the reflection paths of these 3 different objects
MEMBRANE SPACES studio course AHO fall 2008
tutors I PROF.MCHAELl U. HENSEL I Prof. Dr. Birger SevalDSon i Defne Sunguroğlu // students I MIRAY OKTEM I LIAM ROTE-HAHRE I YÜ CHEN 14
Digital Modelling
For digital modelling we used rhino with a relaxation script for surfaces and meshes.The amount of squads define the smoothness of the resulting object. But it takes also calculating resour-ces.parameters we can set is, geome-trical links and tension factor for each point.The modelling of a barrelwith interconected points was a real task for us.To have to points linked but not fixed in the space we have to weld them together and relaxe at the same time. To weld the right point to each othertakes a long time.Also the shapes turned out not to be the way we expected it.we produced a lot of useless shapes, but learned a lot about digital modelling.
MEMBRANE SPACES studio course AHO fall 2008
15
Digital Modelling
For digital modelling we used rhino with a relaxation script for surfaces and meshes.The amount of squads define the smoothness of the resulting object. But it takes also calculating resour-ces.parameters we can set is, geome-trical links and tension factor for each point.The modelling of a barrelwith interconected points was a real task for us.To have to points linked but not fixed in the space we have to weld them together and relaxe at the same time. To weld the right point to each othertakes a long time.Also the shapes turned out not to be the way we expected it.we produced a lot of useless shapes, but learned a lot about digital modelling.
Digital Modelling
we also tried to simulate a droping ball on a surface. For this we used Autodesk Maya.The first problem was to import a surface into maya wihtout kee-ping the bounding box.in our first tries the ball alway drops of the bounding box, wihtout tou-ching the membrane.The second task was to make the membrane a textile. we used the nCloth function.The problem was that the n Cloth scrpit can make a surface reacting like a textile butt not as a elastic textile. The mebrane always starts to flut-ter when we added gravity to it.Also the ball sometime just ignores the membrane and dropes through it.