3D Printering: Laser Cutting 3D Objects

3D printing can create just about any shape imaginable, but ask anyone who has babysat a printer for several hours, and they’ll tell you 3D printing’s biggest problem: it takes forever to produce a print. The HCI lab at Potsdam University has some up with a solution to this problem using the second most common tool found in a hackerspace. They’re using a laser cutter to speed up part production by a factor of twenty or more.

Instead of printing a 3D file directly, this system, Platener, breaks a model down into its component parts. These parts can then be laser cut out of acrylic or plywood, assembled, and iterated on much more quickly.

You might think laser-cut parts would only be good for flat surfaces, but with techniques like kerf bending, and stacking layer upon layer of material on top of each other, just about anything that can be produced with a 3D printer is also possible with Platener.

To test their theory that Platener is faster than 3D printing, the team behind Platener downloaded over two thousand objects from Thingiverse. The print time for these objects can be easily calculated for both traditional 3D printing and the Platener system, and it turns out Platener is more than 20 times faster than printing more than thirty percent of the time.

You can check out the team’s video presentation below, with links to a PDF and slides on the project’s site.

Thanks [Olivier] for the tip.

Continue reading “3D Printering: Laser Cutting 3D Objects”

Tablet Interacts With Magnets, How Does That Work?

Making computers interact with physical objects is a favorite of the HCI gurus out there, but these builds usually take the form of image recognition of barcodes or colors. Of course there are new near field communication builds coming down the pipe, but [Andrea Bianchi] has figured out an easier way to provide a physical bridge between computer and user. He’s using magnets to interact with a tablet, and his idea opens up a lot of ideas for future tangible interfaces.

Many tablets currently on the market have a very high-resolution, low latency magnetometer meant for geomagnetic field detection. Yes, it’s basically a compass but Android allows for the detection of magnets, and conveniently provides the orientation and magnitude of magnets around a tablet.

[Andrea] came up with a few different interfaces using magnets. The first is just a magnets of varying strengths embedded into some polymer clay. When these colorful magnetic cubes are placed on the tablet, [Andrea]’s app is able to differentiate between small, medium, and large magnets.

There are a few more things [Andrea]’s app can do; by placing two magnets on an ‘arrow’ token, the app can detect the direction in which the arrow is pointing. It’s a very cool project that borders on genius with its simplicity.

You can check out [Andrea]’s demo video after the break.

Continue reading “Tablet Interacts With Magnets, How Does That Work?”

Acoustic Barcodes Deliver Data With A Fingernail And Microphone

Either through QR codes, RFID, or near field communication, there seems to be some desire to share tiny pieces of data in a more physical and accessible form. [Chris Harrison], [Robert Xiao], and [Scott E. Hudson] of the HCI Institute at Carnegie Mellon have come up with a fairly interesting solution of making data more physical. They call it Acoustic Barcodes, and it’s able to store over a billion unique IDs in a small strip of plastic.

By engraving a barcode pattern into a piece of wood, stone, glass, or plastic, the guys then attached a microphone to the barcode and ran their fingernails across their invention. A computer interprets the sounds of a finger scraping against the acoustic barcode and produces a series of 1s and 0s.

This binary code can be used to look up various items in a database, or perform actions on a computer. In the video after the break, you can see these acoustic barcodes attached to a whiteboard to provide real tactile control of a video projector.

You can check out a PDF of the Acoustic Barcode paper here.

Continue reading “Acoustic Barcodes Deliver Data With A Fingernail And Microphone”

Tracking Eye Movement By Measuring Electrons In The Eye

[Luis Cruz] is a Honduran High School student, and he built an amazing electrooculography system, and the writeup (PDF warning) of the project is one of the best we’ve seen.

[Luis] goes through the theory of the electrooculogram – the human eye is polarized from front to back because of a negative charge in the nerve endings in the retina. Because of this minute difference in charge, a user’s gaze can be tracked by electrodes attached to the skin around the eye. After connecting eye electrodes to opamps and a microcontroller, [Luis] imported the data with a Python script and wrote an “eyeboard” application to enable text input using only eye movement. The original goal of the project was to build an interface for severely disabled people, but [Luis] sees applications for sleep research and gathering marketing data.

We covered [Luis]’ homebrew 8-bit console last year, and he’s now controlling his Pong clone with his eye-tracking device. We’re reminded of a similar system developed by Atari, but [Luis]’ system uses a method that won’t give the user a headache after 15 minutes.

Check out [Luis] going through the capabilities of his interface after the break. Continue reading “Tracking Eye Movement By Measuring Electrons In The Eye”

Pen Based Input Improvements

[youtube=http://www.youtube.com/watch?v=EcE3XBytN-U]

Lately we’ve been focusing on multitouch technologies, but that doesn’t mean there isn’t interesting research going on in other areas of human-computer interaction. [Johnny Lee] posted a roundup of some the work that [Gonzalo Ramos] and others have done with pen based input. The video embedded above shows how pressure can be used to increase control precision. Have a look at his post to see how pen gestures can be used for seamless workspace sharing and how pen rolling can give additional control.