Multitouch Surface Computer

I’m sure many of you have learned about Microsoft’s Surface.  Sure it’s a cool toy, but its a $12,000 toy.  After doing a bit of research and investigation, there is a whole community out there that are making their own versions of Surface, which is a multitouch surface computer at a fraction of the cost.  I have read stories of people building them for less than $1,000.  I have dreams of building my own and keeping it on a really tight budget, luckily, I have some old spare computers lying around which help offset that cost.  I would turn mine into a coffee table with some features that I haven’t seen in other homemade MSCs which I will reveal when I get an opportunity to build mine.

The basic theory behind how this works isn’t the use of a touchscreen like you have at ATM’s or to place a sandwich order.  It actually uses a projector to shine the image onto a piece of acrylic.  I know what you’re thinking; the projector isn’t going to focus on the acrylic since its clear.  When building it, you essentially glue on a sheet of silicon or a number of other materials which create a surface to hold an image as well as give a good feel for your hands while interacting with the computer.  I also know what else you’re thinking.  How does it know when I am touching it then?  Simple, the edges of the acrylic are lined with IR LED which shine into the acrylic.  A property of acrylic is that it doesn’t let light escape it, so the IR light just keeps bounding around in the acrylic effictivly lighting it up with an invisible color of light.  Then, a modified webcam (to filter out visible color) is placed in the bottom middle of the housing of the MSC which will detect a touch from an object.  When a finger is placed on the acrylic, it will cause the light to scatter from that point which enables the camera to see it.  The computer on the inside has software which will eliminate noise from the camera as well as run software to provide a nice interface for the user to play with.  This is only a basic explanation, a lot more detail can be found on Maximum PC’s website as well as at the NUI Group’s website.  Hopefully I can start on this project early summer and have it done in a few weeks.  Below is a video of Microsoft’s Surface which has capabilities beyond those of the open-source software, but doesn’t have the same amount of fun or learning experience.  It’s also over $10,000 cheaper too, so I think it’s a fair tradeoff.