Janus: The Gatekeeper

September 29, 2012 by Jeremy Cook 10 Comments

[Piet] wrote in to tell us about his hack that allows for his front gate to be opened without a key. Unlike this hack that we featured in August, you don’t need a subway pass, just a good memory. As explained in his article (and the video after the break) if the proper sequence of doorbell rings is input, the gate unlocks itself.

For hardware a [mehduino] is used to take the doorbell input and decide whether or not the “secret knock” has been achieved. The door can be unlocked remotely via a button on the processor. Reprogramming the code is achieved by simply holding the program button while the code is entered on the “remote ringer” button.

Be sure to check out the video after the break to see this lock in action. The housing application may not be exactly what you expect. Also of interest, is that in true hacker fashion, the bare processor is hanging by a hook on his wall! Continue reading “Janus: The Gatekeeper” →

Zelda Engagement Ring Box Seals The Deal

September 26, 2012 by Mike Szczys 22 Comments

Congratulations to [John Scancella] and his wife to be. Their recent engagement was aided by one of [John’s] projects. Since [Betsy] is a big fan of Zelda, he thought it would be fun to present the ring with the Zelda music playing in the background. He and a friend combined forces to build what you seen in this image.

The music is played by an Arduino with the help of a wave shield. This is pretty much a one-use item so battery life was never a concern. A magnetic switch was used to detect when the box was opened and start the music playing.

You can see the full-sized images after the break, but we can tell that [John] went with a traditional engagement ring. We’re still waiting to see if 3D printed rings are going to catch on in the geek scene. If you just can’t give her anything but precious metal there’s always the idea of encoding messages on the band itself.

Continue reading “Zelda Engagement Ring Box Seals The Deal” →

Personal Energy Orb Prevents Your Life From Being Swallowed By The Internets

September 25, 2012 by Mike Szczys 14 Comments

We love the Internet, but we are definitely guilty of losing track of the time we spend traipsing around our virtual haunts. This project will not only remind you to get out and exercise, it will cripple your digital experience if you don’t heed its colorful warning.

[Janko Hofmann] calls it the Personal Energy Orb. It’s really just an Arduino and an RGB LED. But as with most creations, the idea is what makes it great. The orb has a dock next to your computer. It tracks how much time you spend online, changing colors as you rack up the hours. If you don’t heed the warning signs of overuse it will even start to slow down your mouse cursor. But never fear. Full functionality can be restored by topping off your personal energy. As you can see above, there’s also a docking station on [Janko’s] bicycle. The orb monitors your mileage, moving out of the red zone so that your computer will be unencumbered the next time you sit down for a long session of flash games. Don’t miss his video presentation embedded after the break.

Continue reading “Personal Energy Orb Prevents Your Life From Being Swallowed By The Internets” →

3D Printed Exoskeleton Helps This Little Girl Develop More Normal Body Function

August 12, 2012 by Mike Szczys 29 Comments

This 2-year-old girl has a condition called arthrogryposis which causes her not to be able to move her arms. But with a little help, her muscles can be strengthened to achieve more normal use of her limbs. This is not the first time that an exoskeleton has been used, but the advent of 3D printed parts makes the skeleton work much better.

Previous exoskeletons were made of metal and were quite heavy. When you’re talking about a 25 pound child every extra ounce counts. Moving to plastic parts lightened the load. Now the structure can be mounted on her torso, using rubber bands to aid her movement until her muscles are strong enough to do it on their own.

Of course to [Emma] this isn’t an exoskeleton. It’s her set of magic arms.

Continue reading “3D Printed Exoskeleton Helps This Little Girl Develop More Normal Body Function” →

Sip-and-Puff Ipod Dock Highlights Assistive Technology

April 26, 2012 by Mike Szczys 18 Comments

Check it out, a Sip-and-Puff Arduino shield. This is an assistive technology that allows the physically challenged to control things using a plastic air tube. Different combinations of sucking (Sip) or blowing (Puff) differentiate between control commands.

In this case the device is used to control an iPod dock, but [Bob Johnson’s] Kickstarter project seeks to put the Sip-and-Puff functionality out there so that it can bridge the control gap no matter what the need. One example that he mentions in the video after the break is a Morse Code keyboard.

This shield uses a pressure sensor to receive input from the plastic tubing. But we’ve also seen it done using mechanical pressure switches. That technique is what was used in the Sip-and-Puff Kayak build.

Continue reading “Sip-and-Puff Ipod Dock Highlights Assistive Technology” →

Reduced-cost Braille Display For Use With Computers

December 24, 2011 by Mike Szczys 12 Comments

Apparently a Braille computer display can cost several thousand dollars. That’s why [David Pankhurst] is working on a low-cost alternative. His offering is an open source version he calls the Audrey Braille Display.

The concept is quite good. This prototype has one line of six Braille characters. Each character is made of two sliding strips containing eight arrangements of bumps. These can make up any character when positioned correctly. Two motors do all the work, one engages a single strip to reposition it, the other moves the first motor to select which strip should move. This is explained quite well in [David’s] most recent post. Or you can get a preview of the physical build here.

The concept is sound, but the refresh rate must be very slow. We wonder if there’s a way to keep one motor stationary and use solenoids to engage a drive shaft on the individual slide rods? This way, every row could be changed at the same time, disengaging when the appropriate slot is reached.

This hardware is much needed until developing Braille technologies actually come to market.

[via Dangerous Prototypes]

DIY RFID Shielded Wallet Keeps Data Thieves At Bay

September 22, 2011 by Mike Nathan 39 Comments

diy_rf_shielded_wallet

[Serge] was in search of a new wallet, but he was concerned about ne’er do wells with RFID readers stealing his data. He could have gone out to the store and plunked down $20-$30 for a shielded walled, but where’s the fun in that? Instead, he decided to make his own.

Using Kevlar-Nomex fabric, he laid out the general structure for his wallet. This ultra-strong fabric has a breaking strength of 500lbs, but blocking RF isn’t exactly its forte. To provide some electromagnetic shielding, [Serge] added a nice uniform layer of silver epoxy to the Kevlar, which carries an added bonus of strengthening the material. He fired up the sewing machine, adding a nylon strip to the exterior of the wallet for reinforcement, then he worked on forming the bill pouch and card holders.

The final result is a plain yet incredibly rugged wallet that’s sure to keep his various RFID-enabled cards safe. We really dig how unassuming the wallet is – no flash, all function. Nice job, we’ll take one!