Dipl.-Arch. Kai Strehlke, ETH Zurich, Lehrstuhl für Architektur und CAAD

"xWORLDS, the implementation of a three-dimensional collaborative sketch tool within the context of a third year design course."

This work is the result of a postgraduate thesis done at the chair for Architecture and CAAD at the ETH in Zurich Switzerland. It proposes a prototype for a three-dimensional modelling tool in a networked environment. The work is composed of two distinct parts. (1) A modeling tool to create three-dimensional objects in an intuitive and interactive manner. (2) A database component to store and retrieve the objects. This modeller has been implemented for the first time in a design course, where students where using the modeller to sketch and interact within a large group to formulate aspects of their design. The Paper focuses on the modeller and on the experience from a one week workshop.

1. Modelling Tool.

The modeling tool operates in two different modes: (A). Composing cubic forms within a limited cubic space. (B). Deforming the composition of boxes by means of their interaction with a separate volume. For the composition of cubes, the user has to drag a cube with the mouse to continue placing cubes in space. Furthermore, he can move and delete the placed cubes. Simple and complex objects can be created this way, in an easy and intuitive manner. For the second mode, the forms are generated by intersecting a volume with an object created previously in the first mode. The volume can be scaled and moved. The part of the existing object located outside the volume remains unchanged, while the part that lies inside it is transformed in the same way as the volume. Complex forms can be created in this way with simple transformations.

2. Database Storage and Retrieval.

The created objects can be stored in a database. Other users can access the objects stored in the database and continue working on them in the same modeling environment. There are two ways to interact with objects from the database. On one side it is possible to substitute the composition of cubes, and keep the distorted framestructure of the currently active object unchanged. On the other side it is possible to initiate a morphing process between the currently active framestructure and the framestructure of an object from the database. This process can be stopped at any time. It is always possible to switch back in the modeling modus and continue work on the object.

3. Workshop at the the School of Design at the Hong Kong Polytechnic University.

A Group of over 100 students were using the tool in a second year design course. The tool has been implemented as part of a workshop in the second half of the design studio. The workshop lasted for one week in which a collective dataset of over 1000 models has been created by the students. Afterwards, a possibility was given to the students to retrieve models from the database and to process them in different software packages or have them physically built by a 3D printer, and then continue working on the physical model.