This week we completed building our first multi-touch table prototype. With customized software, a 50″ diagonal surface, and a resolution of 1280 x 720 the table is designed to accommodate multiple simultaneous users. The table is comprised of a short throw projector, infrared LEDs, two infrared cameras, and projection screen which adheres to the tempered glass top. The framing material is extruded aluminum. We sourced the materials from all of the world; Hong Kong, the Netherlands, Canada, Japan, and the US.
The base software that communicates with the infrared cameras is called Snowflake and is developed by Natural User Interface, a company in Sweden. We’re developing a gesture recognition library in Flash, that will allow us to plug in support for various gestures in the exhibits that we develop.
The screen shots (above) show how the software detects the drawing of circle. The green lines represent extensions of line segments captured when the finger is moved across the table surface. The yellow points show intersection points, the final point of interest is where the circle is closed. By detecting that point we can distinguish between circles, infinity signs, and spirals using basic topology. This is just one of many gestures were exploring.
This first table prototype has led to designs for a production version that we will be installing this winter at the Don Harrington Discovery Center in Amarillo, Texas. We’ll be conducting user-testing there as we work through the design challenges that a multiple user and gesture-based interface presents. Our first application will be a mashup allowing museum visitors to explore satellite maps and photographs. A similar application is also in the works for the Vulcan Park and Museum in Birmingham, Alabama to be installed in Spring of 2009.
We’re excited about the potential that multi-touch and multi-user exhibits present. Visitors can easily collaborate and communicate around these table-top exhibits. The use of intuitive gestures can allow us, as designers, to move away from traditional graphical user interfaces and toward a set of more natural and intuitive controls.
We’ve proposed a full-day workshop on multitouch and Internet applications for the Museums and the Web 2009 Conference. I’ll write another blog post once the workshops for the conference are announced. We’ll post more updates as we continue to work on these exhibits.
Update February 4, 2009: We’ve released our multitouch table you can check out a video and get the full specifications.