This Tangible User Interface allows the user to draw with everyday objects as ink. It is aimed at four year olds and upwards. It allows them to explore colours, movements and textures by “picking-up” everyday materials and drawing with them.
It looks like a regular large paint brush but has a video camera with lights and sensors inside it.
Pick and drop is a pen based direct manipulation technique that lets the user transfer a computer document from one computer to another. Smart pens are available as office handwriting tools. They capture detailed hand written notes.
I/O Brush allows people to take colour, texture, and movement of any physical object through the tangible drawing tool and immediately draw with that attribute using the same tool. It is a drawing tool of both an input and an output device.
Historically, before paint was sold in stores, artists searched for colors and patterns in real life and nature. In their art, artists tried to simulate the palette of colors they saw in nature. In the process, they extracted colors directly from clay, rocks, sand, and minerals. That is how the colors and pigments we use today came to exist.
The I/O Brush system is made up of two components; the brush and the drawing canvas.
- CCD video camera – Charged-Coupled Device. This is a major technology for digital imaging. It is a rectangular chip with a surface built of an array of light sensitive areas (Pixels).
- Light bulbs around the CCD
- Touch Sensors: Spring based, Flexible/Bendable.
When the brush touches a surface, the lights around the camera briefly turn on to provide supplemental light for the camera. During that time, the system grabs the frames from the camera and stores them in the program. Also, woven into the brush tip are 150 optical fibers. Once the “ink” is captured, the fiber optics light up, i.e., the brush tip is lit up, to indicate that the brush has picked up ink from that surface.
- Wacom Cintiq Screen with a built in graphics tablet.
The coil of the Wacom pen tip is embedded inside the I/O Brush’s tip to allow the system to detect the presence or absence of the brush on the canvas.
There are three modes for picking up ink; Texture, Colour, Movement.
The Texture mode captures a snapshot of the brushed surface, which consists of one frame.
The Color mode computes the RGB values of all the pixels in the captured frame and returns the most common RGB value so that the user can draw with a solid color.
The Movement mode grabs up to 30 consecutive frames of the brushed surface and lets the user draw with the movement. When the user moves the brush across the canvas, the system drops off the
successive frames, but the end of the stroke shows the captured 30-frame animation in a loop.
The paint in all three modes is masked to appear as a roundshape and its translucency level is set to a slightly lower value so that the user can layer ink like water color by quickly moving the brush.
The user can paint with thick color by slowly moving the brush. The brush allows the user to paint with the same ink indefinitely until s/he picks up different ink.
The modes are switched by the simple turn of dial on the neck of the brush.
The soft acrylic hair from real paintbrushes was transplanted onto the tip of I/O Brush, giving it the authentic feel of a soft brush tip.
- Important to make the brush wireless.
- Multiple brushes for more collaborative drawing activities.
- Physical control over the brush, such as pressure and tilt sensitivity.
- Incorporating non-visual properties, such as sound into the brush. Synesthetic drawing tool that does not only pick up visual properties but also auditory elements of the world we live in. I/O Brush could extract from these samples properties like music genre and associate a color palette and patterns with them. E.g., aggressive, fast music, could create dark lines with jaggy patterns and high opacity, where as soft flowing, slow new age music would result in pastel colors with smooth patterns and high transparency. – Considerable challenge.