Introduction

This project is an attempt to create a dynamic, gesture based, architectural modeling software. In WetSpace, the design process is a performative act, where the user engages with a set of forces and flows in order to model space.

In order to more fully link the body to the software, we developed an Intertial Momentum Unit (IMU) to be used as a three dimensional input device. The real-time translation and rotation of the device is streamed wirelessly to the modeling software, allowing the user to control the design process with this data.

The software itself uses a physics simulation to model an architecture based on networks of particles, forces, and springs. Using these three components, we were able to map the user's input into an architectural section that flows through active space. This section is captured at a regular interval and forms a cloth-like surface that itself can be manipulated and modified. The physical simulation never stops, but the design reaches metastable states.

Inertial Momentum Unit

The IMU is a wireless interface device that registers acceleration in three directions (x,y,z) and rotational velocity about two axes (x,y). A custom circuit has been designed that conditions the analog signal from accelerometers and gyroscopes and streams the digital data over a bluetooth network. Within the software, this data is parsed into useful values, such as the absolute rotation of the device, as well as translational 'notes' in each direction.

This Quicktime movie gives an explanation of the IMU in action. Note that it is 71 Mb in size.




Hardware Design

The IMU grew out of work done in Joe Paradiso's class, MAS.863 Sensor Technologies For Responsive Environments. It was expanded and refined in Joe's musical controllers class in the fall of 2006.

The device uses a 3 axis MMA7260Q accelerometer from Freescale Semiconductor, and a dual axis IDG300 Gyroscope. The 3.3V signals from these chips are conditioned with active lowpass filters and amplified to 5V before they are converted to digital and streamed to bluetooth by and AVR Atmega32 Microcontroller. The board itself has been designed in two parts. The IMU chips, amplificaton and bluetooth populate a daughter board that interfaces with the No.6 AVR platform designed by the Computing Culture Group at the Media Lab.

Audio Feedback

The IMU uses audio feedback to describe its data to the user. A background hum gives the user a sense of the global rotation of the devices, while a series of five tones correspond to the strength of the velocity of acceleration in each of the five degrees of freedom: translation in x, y, and z, and rotation in x and y. Finally, a series of samples are played back when the logic of the device senses a movement in either direction of these five degrees of freedom.




Active Environment

The modeling process happens in three stages. First, the user models the site by placing point forces of various strengths and positions corresponding to site conditions. Once the user has refined this site, they can draw a section within the site. The section becomes an active network of nodes and springs and drifts through the environment, responding to the point forces. The user can steer the section with the IMU and also control parameters such as its spring strength and damping. Once the user has stopped capturing the section, they can find specific points in the cloth mesh and modify them with the IMU. Because the surface is also linked through a network of springs and particles, it too deforms in a fluid and interconnected way.



Gestural Sketch

This software is designed as a sketching environment based on physics simulation. It is not meant to replace existing CAD software, but rather to provide a more fluid alternative. The results of a system based on simulation would be difficult to arrive at through other means of design. It probably most advantageous to use this software to design components of a larger architectural production.

The software is written in Java and is visualized with the Processing core libraries. The physics simulation was developed by Jeffrey Traer Bernstein.