led-contacts

[Ben Krasnow] Sticks LEDs In His Contacts Just For Kicks

[Ben Krasnow] wrote in, saying that every so often a news story appears covering a project in which researchers embed a single pixel LED display inside a contact lens. The most recent article he saw featured a contact-wearing rabbit, and not being one to shy away from damaging his own body in the name of science, he decided to try the experiment on himself.

He started out by soldering a tiny 0402 SMD LED to a hand wound coil, laminating the display between a pair of regular contact lenses. After trying to adhere the lenses to one another using water, he opted to tack the edges together with a pair of hot tweezers, making for a more secure but uncomfortable piece of eyewear. The LED is powered by a simple inductive coil he put together, which uses a spark gap transmitter to flash the LED on and off.

If you’re not freaked out by people sticking things in their eyes, be sure to check out the video below to see [Ben’s] augmented contact lens in action. While it might not give him Terminator-like vision, it’s pretty awesome considering he pieced it together in his workshop in his spare time.

Continue reading “[Ben Krasnow] Sticks LEDs In His Contacts Just For Kicks”

Keep Others From Snooping In Your Digital Life

In our digital age prying eyes are everywhere. The sad thing is that they may even belong to your own government. But no matter who it is, there are some things you can do to keep your private digital devices and content as secure as possible.

The link above goes to [Jerry Whiting’s] discussion on the topic. He’s certainly an interesting speaker, but make sure you’re using headphones at work as the language can be a bit sultry once in a while. He aims the lesson at the Occupy movement, but it’s a fun listen for any conspiracy theorist out there. The topics run the gamut, starting with the specter of physical access, then moving on to protecting your network through traffic analysis and using key pairs. This Security 101 segment comes in two parts (the first one is embedded after the break), each a bit more than thirty minutes. He’s planning to post a second lesson covering hashes and encryption. Continue reading “Keep Others From Snooping In Your Digital Life”

Motorized Camera Mount Unexpectedly Popular For CNC-aimed Hardware

Here’s a camera mount that moves smoothly along a motorized sled. [Bart Dring] created the system and was surprised by it’s popularity, having received several sales requests from photographers. He originally designed the linear bearing system, called the MakerSlide as an inexpensive alternative to other CNC machine solutions. Allowing a computer to map out timed movements for video shots wasn’t on his radar then, but as you can see in the clip after the break, the MakerSlide does an amazing job at it.

The modular track system makes it easy to attach to a base. In this case, a couple of pieces of acrylic let him support both ends of the track on standard camera tripods. [Bart] mentions the knowledge gap between people who work with CNC milling hardware and photographers as an issue in deciding how to control the system. Since photographers aren’t likely to be proficient in EMC2, he designed a control application with an Arduino. It uses a stepper motor controller shield, and does some fancy math to make sure there is smooth acceleration, etc.

Continue reading “Motorized Camera Mount Unexpectedly Popular For CNC-aimed Hardware”

Hack Removes Ads From Kindle ‘Special Offers’ Hardware

We figured it wouldn’t be long before someone figured out how to remove the ads from the ‘Special Offers’ versions of the Amazon Kindle hardware. There are two things that made this obvious to us, the huge flaw that lets code be easily run as root, and the MP3 tag forming that makes it possible to unlock the device.

[Pat Hartl] knows his way around a *nix shell, so once he gained SSH access to the device he started a search for the ad images that make up the special offers feature. He found them in a few different places, making backups of the files in an alternate location, then removing them with some simple commands. He even rolled the process into a one-click installer like the Jailbreak package. It makes us wonder if Amazon has a way to tell if your device is not longer pulling down content for these offers?

At risk of sounding preachy, Amazon does offer this hardware without ads for a one-time fee. Circumventing the unobtrusive ads may lead to higher hardware prices in the future, and [Pat] mentions that. He pulled off this hack to show the holes in Amazon’s security, and hitting them in the pocketbook is a powerful way to do it.

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Automatic Flashlight Tag Damage Sensor

You’re out at night and playing a boisterous game of flashlight tag. But how can you tell if you’ve been mortally wounded by your opponents light beam? [Kenyer] solved this problem by building a flashlight tag damage sensor which is worn by each participant. It adds a bit of the high-tech equipment used with laser tag while keeping a low-tech price tag.

The sensor relies on a light dependent resistor to register hits when a flashlight beam passes through the round window. It will only register one hit in a three-second time period. At the end of the game, the total number of hits recorded can be flashed back using an on-board LED to see who is the victor. You can see a demo of this functionality in the clip after the break.

[Kenyer] started with a breadboard prototype using an Arduino as the driver. Obviously the cost of an Arduino for every player is a bit ridiculous. He scaled down the project, running the Arduino code on an ATtiny microcontroller. Continue reading “Automatic Flashlight Tag Damage Sensor”

The Most Evil Gift Ever

[form], a new user on the Hack a Day forums, was thinking, “what Christmas present i can send a friend, that would be really annoying?” We think he really hit it out of the park with this one. It’s a modified computer speaker that will play “explicit” audio until the power button is pressed 200 times and the light sensor is covered. When this present is unwrapped, the room will fill with sounds not suitable for children, the elderly, or those with heart conditions.

The build is based around an old powered computer speaker. Six Li-ion batteries from an old laptop provide the power, and a very simple circuit pulls sound off an SD card with the help of an ATtiny45.

The schematic for the build looks easy enough, and like a good builder, [form] included the source and HEX files. Sadly (or thankfully), there is no video of the gag gift in action; probably a good thing, because this seems like a great way to lose a friend.

Computer-aided Paint Brush

[Nirav] painted this masterpiece by hand… with a little help from a computer. He calls it the semi-automatic paintbrush because you do need to move it over the canvas by hand, but a computer decides when to dispense the ink.

He’s using a piece of hardware we looked at back in September called the InkShield that got a boost from Kickstarter. It’s an Arduino shield that drives an inkjet printer cartridge. The trick is how to know when the cartridge is in position for printing.

The system uses visual processing for that. [Nirav] added an IR led to the cartridge, and uses a camera to extrapolate its position. He actually reused a Python homography module which he had written for use with a projector. That setup was developed as a digital white board, but works just as well for this purpose.

He mentions that results like this won’t be featured in an art museum. But the look is unique, and we’d love to make a set of geeky thank-you notes using the technique.