[Matthiew] needed to create a system that would allow a computer to read braille. An electromechanical system would be annoying to develop and would require many hardware iterations as the system [Matthew] is developing evolves. Instead, he came up with a much better solution using a webcam and OpenCV that still gets 100% accuracy.
Instead of using a camera to look for raised or lowered pins in this mechanical braille display, [Matthiew] is using OpenCV to detect the shadows. This requires calibrating the camera to the correct angle, or in OpenCV terms, pose.
After looking at the OpenCV tutorials, [Matthiew] found a demo that undistorts an image of a chess board. Using this same technique, he used fiducials from the ARTag project to correctly calibrate an image of his mechanical braille pins.
As for why [Matthiew] went through all the trouble to get a computer to read braille – something that doesn’t make a whole lot of sense if you think about it – he’s building a braille eBook reader, something that just screams awesome mechanical design. We’d be interested in seeing some more info on that project as well.
Embedded above is a neat augmented reality business card by ActionScript developer [James Alliban]. After seeing “the most impressive business card you will ever see“, he was inspired to update his own business card. His new card has a fiduciary marker on the backside and directs you to his site. A flash app on the site displays a video where he tells you more about himself. The 3D grid of planes in the video varies in depth based on the brightness of the section. He has a few more AR and tracking demos on Vimeo.
Updated: While we’re talking augmented reality, it’s worth checking out the tech behind ESPN’s baseball tracker that uses doppler radar.
Related: Augmented reality in Flash
[via Josh Spear]
Reader [Ramon Viladomat] sent in what he has been working on over the last year at the Universitat Pompeu Fabra in Barcelona. Tired of see nothing but zooming map demos, he created a roleplaying game that takes advantage of the reacTable‘s multitouch interface. Along with multitouch, the reacTable also uses tangible fiducial markers to represent objects and as an alternative input method. Embedded above is a video demoing the interface and gameplay (starts at 3:43). The game lets you move your miniature through a virtual world. The surface shows you how far you can move dynamically as your action points regenerate and slowly reveals more dungeon as you discover it. You can pause the action and use gestures to set attack patterns. We really like this demo and would love to see someone build one using a popular tabletop game like Warhammer 40K. Embedded below is a demo of the associated map editor.
Continue reading “Multitouch tabletop gaming”
We were surprised last month when we saw augmented reality being done completely in flash. It hasn’t taken too long to go mainstream though. MINI has incorporated it into a recent German language magazine ad campaign. The fiduciary marks actually work quite well with MINI’s established ad format. Visit the ad’s URL and hold the magazine up to the webcam and a 3D model of the MINI Cabrio will appear. They have a PDF of the ad that you can print and use if you don’t have the original. Unfortunately, it doesn’t seem to have cross-platform support.