OPEN QUESTIONS 
Unsolved problems of pneumatic structures in biology. 
A compilation of conceivable subjects of research. 
Status September 1977. 
Under the guideline ’How to proceed further ?’, the 
Institute of Lightweight Structures (IL) is collecting 
unsolved tasks of science, technics and art for research 
and instruction. 
These are subjects relating in one way or another to the 
scope of work of IL, Sonderforschungsbereich 64 and 
biology. Most subjects have not been investigated up 
to date. For some of them, IL has already compiled 
documentation : these are marked (IL) in the catalogue 
The purpose of this selection is to inspire their solution 
by the most varying kinds of specialists. If desired, IL 
will assist in such work. We however request you to 
inform us of planned research work, just as IL always 
informs on its research planning. 
Task compilations of additional fields of subjects are 
planned and will be published in subsequent IL issues 
and IL-INFOs. 
The task formulation is very unprecise in some cases 
and still superficial. 
We kindly request all readers to submit proposals for 
improvement. 
That section of the task compilation which is published 
herein exclusively deals with open questions of the 
subject cbmplex of "pneus in living nature”. This also 
includes pneus of non-living nature, e.g. microspheres 
which are important for the development of the world 
of forms of living nature. Technical pneus, such as air- 
supported halls, tubes, containers or sails, have not 
been dealt with herein. 
At the end of every individual question, disciplines 
(marked D) were proposed which may be able to contri- 
bute solutions individually or jointly: 
ANTHROpology HYDroMECHanics 
ARCHitecture INFOmatics 
BOTany LIGHTweight Constr. 
CHEMistry MATerials Testing 
CINEmatography MECHanics 
CYTOlogy MEDical Science 
DYNamics METeorology 
ECOlogy MODel Testing 
EMBRY Ology PALAEOntology 
ENGineering PHIiLosophy 
ETHOlogy PHYSics 
FINE Arts PSYCHology 
GENetics SOCIOlogy 
GEOdesy ZOOlogy 
HYDroDY Namics 
Please send your letters to IL, attention Mr. Jürgen 
Hennicke who supervises the overall catalogue of tasks. 
ABNORMALITY: Investigation of abnormalities of 
»ological pneus and their genetic or environmental 
causes for plants, animals and man. Consequences 
of abnormalities of biological pneus for behaviour, 
evolution and selection. > Behaviour, esthetics, world 
of forms. D: Anthro, Arch, Bot, Eco, Etho, Fine, Gen 
Psych, Zoo. 
ACOUSTICS: Generation, amplification and absorp- 
tion of sound by biological pneus, e.g. sound bladder 
of frogs, tensioned sound membranes. > Loading, 
vibration. D: Anthro, Bot, Eng, Phys, Zoo. 
ALTERATION: The influence and alteration of the 
appearances of biological pneus by man, e.g. by 
sreeding plants and animals, agriculture, destruction 
>f environment. Relationship between formal alteration. 
rreeding and selection. Influences on human and 
inimal behaviour. > Art, behaviour, esthetics, selec- 
ion, world of forms. D: Arch, Bot, Etho, Fine, Gen, 
Psych, Zoo. 
ANIMAL: Classification and arrangement of the pneu- 
matic structural systems and members in zoology, 
alteration processes of initially pneumatic systems by 
stiffening or hardening. (IL). > Calculation, form 
generation, growth, material, surveying, world of 
“orms. D: Arch, Chem, Eng, Geod, Light, Mat, Mod. 
Zoo. 
ANIMAL, stiffened: The forms of pneumatic animal 
sodies prior to and after stiffening, intermediate stages 
“orm deformations and alterations of the load-bearing 
vehaviour as a result of stiffening. Chemical and 
ohysical processes. > Chemistry, form generation, load 
material, world of forms. D: Arch, Eng, Geod, Mat, 
700. 
ANIMAL STRUCTURES: The employment of pneumatic 
‘tructural members and systems in animal structures, 
2.g. Laying of eggs, cocoons, nests. The influence of 
the animal body form on the animal structure form. 
IL). > Animal, function, material, structural system, 
world of forms. D: Arch, Etho, Eng, Zoo. 
ART: Artistic aspects of the pictorial representation of 
siological pneus (Heckel et alii) and their utilisation 
35 an artistic means of expression in painting, graphics, 
slastics and advertising. Alteration of the forms of 
siological pneus in artistic presentation. > Alteration, 
sehavior, cinematography, esthetics, photography. 
D: Anthro, Arch, Bot, Cyto, Etho, Psych, Zoo. 
3EHAVIOUR, animal: The effect of biological pneus 
as a function of form, form deformations and colour on 
the behaviour of animals and vice versa, e.g. impressing 
attitude, mimicry, sexual behaviour. > Alteration, 
perception, selection, signal, world of forms. D: Arch, 
Etho. 
BEHAVIOUR, man: The sensation and behaviour of 
nan when observing biological pneus. Quality of 
axperiencing forms of the macro and micro ranges 
and interiors of man, animal and plant not yet viewed 
sefore. Questions of dimension, standard of values, 
1ction and reaction, form and colour. > Esthetics, 
serception, sexual signal, signal, taboo, world of 
‘orms. D: Anthro, Arch, Etho, Fine, Phil, Psych, 
Soci. 
3IC: Experimental determination of BIC values of bio -~ 
ogical pneus, determination of material expenditure 
and load-bearing capacity, e.g. under bursting pressure 
ndividual loads, uniformly distributed external loads. 
Comparison to technical structures. (IL). > Expenditure 
material, structural member, structural system. D: 
Anthro, Arch, Bot, Eng, Mat, Zoo. 
BUDDING: Pneumatic actions and mechanisms during 
the unfolding of buds into flowers and leaves. (IL) . 
> Motion, plant. D: Bot, Cyto, Eng, Phys. 
BUDDING, micro-shelf: Experimental investigations 
‘or the artificial creation of buddings of micro-shells, 
2.g. by increasing the intemal pressure etc. > Micro- 
shell, water pneu, world of forms. D: Chem, Cyto, 
Eng, Mod, Phys. 
BURSTING PRESSURE: Bursting pressure investigations 
of biological pneus in the macro and micro range, e.g 
axternal skins (epidermis) and internal skins of animals 
and plants (cells, intestines, bladders). Tensioning and 
2longation at different loads, until the bursting pressure 
is reached. > Calculation, load, model testing, 
iurveying. D: Bot, Cyto, Eng, Mat, Mod, Zoo. 
CALCULATION: Development of methods for calculatine 
stresses and their distribution, as well as deformations 
of biological pneus under different loads, e.g. intemal 
oressure, external pressure, extemal stresses. Variation 
range and critical values of loadability . Compilation 
of existing calculation methods under the viewpoint 
of applicability to biological pneus. > Bursting pressure 
‘oad, surveying, tension testing. D: Eng, Geod, Mat, 
Mod . 
CELL: Consideration of the biological cell and its in- 
dividual elements as a pneuamtic system, form and 
load-bearing behaviour, classification and arrangement 
of the various types under pneumatic aspects, for plants, 
animals and man. (IL). > Cell association, cell division 
form generation, structural system, world of forms. 
J: Anthro, Arch, Bot, Cyto, Gen, Zoo. 
CELL, load-bearing behaviour: Investigation of the 
change in the form of cells and cell associations under 
varying stresses, e.g. intemal or external pressure, 
in particular the processes during cell division and 
sell fusion. Analysis of the stresses and stress variations 
'n the cell membrane. > Calculation, cell division, 
oads, structural member, structural system, world of 
‘orms. D: Anthro, Arch, Bot, Cyto, Chem, Eng, Geod 
Light, Phys, Zoo. 
ZELL ASSOCIATION: Classification and arrangement 
»f cellfiiled biological pneus, forms and load-bearing 
sehaviour, functions, for plants, animals and man. 
Zell associations and cell colonies. > Cell, cell 
division, foam, structural member, structural system, 
world of forms. D: Anthro, Arch, Bot, Cyto, Eng, 
Seod, Zoo. 
CELL ASSOCIATION, load-bearing behaviour: Form 
and design of the link between individual cells, develop- 
nent and strength, dissolving capability, form deformatior 
snder intemal or extemal stresses. Permeability, types, 
‘or plants, animals and man. > Cell, cell division, 
structural member. D: Anthro, Arch, Bot, Chem, Cyto. 
fng, Geod, Light, Phys, Zoo. 
CELL DIVSION: The types and speeds of form defor- 
nations during cell divsion and cell fusion as a function 
of membrane stresses, intemal pressure, external pressure 
chemical influences. Determination of critical min. 
nd max. values, possibilities of influencing from out- 
side. (IL). > Cell, cell association, load, structural 
system. D: Anthro, Bot, Cyto, Eng, Gen, Zoo. 
CHEMISTRY: Chemica! influences on forms, pressures, 
.oad-bearing capacity of biological pneus. Particulari- 
ties of various development stages. Chemical processes 
within biological pneus, couses and effects. > Animal 
"orm generation, man, medium, plant, water pneu, 
world of forms. D: Anthro, Bot, Cyto, Geod, Eng, 
Phys, Zoo. 
ZINEMATOGRAPHY: Shooting of films (slow-motion 
1ormal, time-lapse, high-speed) and photos for 
itudies of form deformations and motional actions of 
siological pneus, selection of particularly significan: 
axamples. Several intemal pressures or extemal 
sressures, different extemal and internal loads and 
types of stress. > Motion, photography, surveying, 
world of forms. D: Anthro, Bot, Cyto, Eng, Fine, 
Seod, Med, Zoo. 
ZOLOUR: The colour of biological pneus, relationships 
setween colour and form, dependencies and combinations 
influences on human and animal behaviour. > Alteration, 
asthetics, world of forms. D: Arch, Etho, Photo, Psych. 
ZOMPRESSION REINFORCEMENT: The initially soft 
zell as the forming element during hardening or stiffening 
»f cell associations, intemally and externally. (IL). 
> Chemistry, cell, foam, form generation. D: Cyto, Eng 
Gen, Geod. 
CONDUCTING SYSTEM: Pneumatic conducting systems 
of plants, animal and man. Classification and arrangemer 
of the species and functions. (IL). > Flow, motion, tube 
system. D: Anthro, Bot, Eng, Info, Phys, Zoo. 
CONTAINER: Investigation of pneumatically acting or 
aneumatically formed containers of plants, animals and 
nan. Classification and arrangement of the various 
<inds and forms, of the different functions and parti- 
sularities. Compilation of strengths and materials. 
‘IL). Function, structural member, structural system 
J: Anthro, Arch, Bot, Eng, Geod, Mat, Zoo. 
ZONTROL: > Motion, perception. 
CRUSTACEA: Investigation of pneumatically generated 
or influenced forms of crustaceae. Growth processes. 
IL}. > Compression reinforcement, growth, material, 
urveying, world of forms. D: Arch, Eng, Geod, Mat. 
700. 
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