3D for everyone - like a magic wand!

A paintbrush that paints without paint is currently on show at Norrköping’s Visualiseringscenter. The technology was developed at LiU, is based on magnetometers and can, in principle, be combined with any tool.

Soon everyone will be able to navigate advanced 3D maps or put a spin on the ball in the ping-pong game. The technology, based on magnetometers, can be combined with a 3D mouse, for example, or a magic wand or - as in a current exhibition at Norrköping’s Visualiseringscenter - with a paintbrush that ‘paints without paint’.

It was actually by chance that a research project at Linköping University (LiU) discovered a whole new way of controlling computers. The project used magnetometers to measure the earth’s magnetic field and thus establish the direction of north, however there were often problems with interference from other magnetic materials in the magnetometers’ surroundings.

So the researchers reversed the logic, mounted several magnetometers behind a computer screen and were thereby able to subtract the earth’s magnetic field and retain the interference. If the interference is from a permanent magnet, the computer is able to calculate its position in three dimensions and its direction of rotation.

Fredrik Gustafsson, Professor of Sensor Informatics at Linköping University explains:

“This means that it is now possible to control the computer’s functions with an ordinary magnet mounted in a tool such as a pen, a brush, a racket or a magic wand. The computer can calculate the tool’s position and direction and, for example, write calligraphy, paint with watercolours, play table tennis with a spin and almost do magic tricks with the computer since there are no visible sensors.”

There are numerous possible applications for what researchers have initially christened the 3D Wand, and one example of what it can do is currently on show at Norrköping’s Visualiseringscenter. In a demonstrator visitors can dip the paintbrush, first in a pot of water without water, then in the paint pots without paint - and then paint on the paper that’s on the table. The paint appears on the paper at the same time as your watercolour takes shape on the screen. You can change settings for different paper textures and different sizes of brush, and the thickness of the strokes also vary depending on the inclination of the brush.

Pretend you’re Harry Potter!

Related Links
Norrköping’s Visualiseringscenter  
Fredrik Gustafsson, Professor of Sensor Informatics at Linköping University

Björn Stafstedt 2012-06-26