INTRODUCTION

Complex geometry of soap bubbles has attracted attention of too many people from different disciplines like mathematics, physics, and computer sciences. A considerable amount of research was done to describe the complex geometry of soap bubbles and their interactions and to simulate them. But it is very difficult to achieve that because of their complex structure.

When soap bubbles cluster and search for equilibrium, intersection rules  operate, which make those geometries interesting and make them more specialized than random spherical geometries and worth studying. The analysis of those rules gave inspiration for more rigid geometry and structure searches. Recent years with the developments in design, soap bubble clusters are also used as a source of inspiration for complex geometries and designing processes. Frei Otto’s studies about minimal surfaces and bubbles, Aquatic Centre from PTW Architects and ARUP, Tomas Saraceno’s installation are some of the examples from design world.

The problem of this research is modelling bubble geometries by abstract and realistic approaches by different graphical programming software in digital environment. By abstraction, researchers were trying to obtain bubble like models and relate them in various ways with real bubbles. By realistic approach, the researchers tried to apply physical rules directly during the modelling to represent their shape and interaction properties and analyzed their implications. The aim is to evaluate those potentials served by those two approaches for the modelling of a complex geometry and its implications for various aspects of design processes.

METHODOLOGICAL PROCEDURES

First a research was done to understand the behavior and geometry of bubbles and explain general rules and laws which shape and affect them.  Mainly the topics studied here is on geometry and mathematical principles of soap bubbles like analytical laws of The Laplace Young and Plateau’s rules, which also includes the principles of bubble interactions.

We ran various graphical programming tools in the modelling process, to be able to profit and evaluate the different dimensional properties of these tools. Next to the dimensional aspect of this diversification also static and interactive simulations were done with those tools which also gave another aspect of evaluation. Tools we used include ‘Processing’, a graphical programming tool to be able to observe the geometries in 2D and ‘Grasshopper’, a parametric 3D modelling tool, for a more practical modelling tool for 3D. Another tool for the realistic simulation of soap bubbles called ‘Surface Evolver’ was also discovered to be used in a lot of scientific research done before and will be researched as a design tool further.

One of the environments that we used to simulate bubbles in 2D in abstract way was Processing. We’ve created a class to define the bubbles, their properties.  Then we’ve written the functions to determine bubbles behavior and relation between each other. The functions that we used to organize their behavior were collision, move, impulse and display. Then we’ve determined number of bubbles and call them from main function. It also interacts with the user. It is possible to control and change the amount of gravity, spring and friction forces number of bubbles and their sizes via keyboard and mouse.

Other abstraction approaches took place in Grasshopper, in a 3D environment. One of them is using Voronoi to represent the soap bubbles. Another one is abstraction of bubbles using human computer interaction using metaballs.

The realistic modelling approach was also done in Grasshopper by imitation of physical rules with the help of Plateau’s Laws. However this model still has to be developed in order to maintain a representation of bubble clusters of more than 3. For these various algorithms additional add-ins or add-ons were installed in Grasshopper and used. Those additional programs will be explained as well.

Another realistic approach is to be planned in Processing. Considering to Plateau’s Law and Young Leplace Equation, it is possible to state those for each planar bubble cluster:

-Each curve is an arc of a circle or a line segment

-Each vertex is the endpoint of three curves at 120 degree angles

-It is possible to assign pressures to the bubbles so that curvature is inversely proportional to pressure difference.

As a dynamic approach we’ve considered the principle proven by John von Neuman in the early 1950's about grain growth. In two dimensional systems, bubbles with more than six neighbors grow, those with fewer shrink, and those with exactly six neither grow nor shrink (though they can change shape).  Future goal of this research is to make a dynamic system; which computes planar soap bubbles, by using those principles.

We explained the difficulties confronted during applications and advantages and disadvantages of different environments we used. With the application of bubble principles, the processes and products will be reviewed.

Another important research aspect in the above process is the possible relationships of our observations with design processes. Also a detailed research on how soap bubbles were used in the different phases of the design has to be put, in order to present a newer insight about soap bubbles.

RESULTS

Two programs, Processing and Grasshopper were used during the programming of bubbles. With the application of those principles, the processes and products was reviewed. Both programs have different potentials, limitations and disadvantages for the designers; those will be discussed during the process.  It was seen that approaching a concept by these various methods and their applications in various tools is very fruitful for design understanding. All of these processes gave different data and their qualities are different, like being static of interactive or to be generative or not.

During the abstract modelling phase in Processing, we’ve had a chance to observe different acceleration circumstances and the effect of the different forces to the movement and interaction of the bubbles.  In Grasshopper the user had to chance to interact with soap bubbles and experienced their separate and united behaviors.

During the realistic modeling phase in Grasshopper the physical modelling gave the insight on the relationships of geometries with defined rules. It was seen that real algorithms unseen geometries lies behind seen geometries and trying to understand and model this reality teaches a lot by its own. We’ve also tried to simulate real bubble-bubble interaction and control the acceleration according to physical laws in Processing but we couldn’t achieved it yet and still working on it. The analysis of Surface Evolver is also expected to give insight on understanding potentials of bubble geometries.

DISCUSSION

By abstraction, different processes emerged, by realistic applications of rules; more limited, defined, but rich outcomes were obtained. Those implications are valuable for computer aided design using inspirational agents.

This research shows that physical agents around us could serve us unlimited design knowledge and various data, behind what is already seen. Designer’s interpretation of those modeling processes and realistic features of the researched agent are educative therefore valuable outcomes.

Lastly the potential architecture and design applications in different aspects, which could be inspired from those approaches and processes, will be researched. Motivation on future research will be presented as a conclusion for the development of the bubble representations.