Light Up Earrings

light up earrings

Unfortunately [ch00f’s] been too busy to write for Hack a Day lately, but he has finished off an awesome little project — Christmas LED earrings!

As with all his projects, there is a brilliant write up that covers everything — even for the stuff that didn’t work. But what we really have to admire about this project in particular is the scale at which he was working. The tiny battery squished in between the two boards? A mere 19mAh. Which is actually enough to power the earrings for a few hours, but is only the size and thickness of a few microSD cards!

The second thing that really popped out at us was the boards themselves, there’s just no room for a programming header! To work around this [ch00f] actually made the PCBs in 3 segments, programmed it, and then cut off the programming header section! If that’s not enough ingenuity, how about this – He also included hall effect sensors on-board to turn them off while charging! Not to mention an intricate wood box to charge them in…

Stick around after the break to see the great demo video, it even has some classy music from the 1930’s which really sets the mood.

Continue reading “Light Up Earrings”

LED Blinds Turn Windows Into Displays

[Dinofizz] is almost done with his vertical LED blinds. The build makes use of 768 diffused white LEDs (10mm size), at a resolution of 48×16, and it only requires one 16-channel LED driver (a MBI5026), which makes use of 3x 4-to-16 demultiplexers. Did we mention it has 16 shades of grayscale too?

At the heart of the many piles of painstakingly soldered wires is an ATmega644A microcontroller which takes care of interpreting the data for the display. He didn’t write the firmware himself though, that credit goes to [Jay Clegg] who does some pretty cool work with Evil Mad Science’s Peggy 2.0 LED driver.

What we really have to admire is the amount of effort he put into this project. He used custom PCBs to daisy chain the blinds together, 300 feet of 16-way ribbon cable, and approximately 4000 individual solder joints! You’d think there would have been an easier way!

Making use of his high rise windows, he now has the ability to broadcast messages for the world to see. After the break check out the video of them in action!

Continue reading “LED Blinds Turn Windows Into Displays”

Extremely Precise Positional Tracking

lumi

A few folks over at Carnegie Mellon have come up with a very simple way to do high-speed motion tracking (PDF) with little more than a flashlight. It’s called Lumitrack, and while it looks like a Wiimote on the surface, it is in reality much more accurate and precise.

The system works by projecting structured light onto two linear optical sensors. The pattern of the light is an m-sequence – basically a barcode where every subset of the m-sequence is unique. By shining this light onto a linear sensor, Lumitrack can calculate where the light is coming from, and thus the position of whatever is holding the light.

Even though the entire system consists of only an ARM microcontroller (in the form of a Maple Mini board), two linear optical sensors, and a flashlight with an m-sequence gel, it’s very accurate and very, very fast. The team is able to read the position at over 1000 frames/second, nearly the limit of what can be done with the Maple’s serial connection.

Already there are some interesting applications for this system – game controllers, including swords, flight yokes, and toy cars, and also more artistic endeavors such as a virtual can of spray paint. It’s an interesting piece of tech, and with the right parts, something any of us can build at home.

You can see the Lumitrack demo video below.

Continue reading “Extremely Precise Positional Tracking”

LED-Guided Piano Instruction

LEDpianoGuide

[Kay Choe] can’t play the piano. Rather, he couldn’t, until he converted his keyboard to include LED-guided instruction. [Kay] is a microbial engineering graduate student, and the last thing a grad student can afford is private music lessons. With $70 in components and a cell phone, however, he may have found a temporary alternative.

The build works like a slimmed-down, real-world Guitar Hero, lighting up each note in turn. We’ve seen a project like this before, with the LEDs mounted above the keys. [Kay]’s design, however, is much easier to interpret. He embedded the LEDs directly into the keys, including ones above each black key to indicate the sharps/flats. An Android app takes a MIDI file of your choice and parses the data, sending the resulting bits into an IOIO board via USB OTG. A collection of shift registers then drives the LEDs.

For a complete novice, [Kay] seems to benefit from these lights. We are unsure whether the LEDs give any indication of which note to anticipate, however, as it seems he is pressing the keys after each one lights up. Take a look at his video demonstration below and help us speculate as to what the red lights signify. If you’re an electronics savant who wants to make music without practicing a day in your life, we recommend that you check out [Vladimir’s] Robot Guitar.

Continue reading “LED-Guided Piano Instruction”

Halloween Doorknocker Decoration Hack

halloweenDoorHack

If you’re new to hacking, Halloween is a great excuse to get started, and [Chuck] has put together an inexpensive animated Halloween decoration that you can show off on your front door. After scoring a $5 plastic Halloween doorknocker from Wal-Mart, [Chuck] gathered together a small pile of components and then set about breathing some life (death?) into its scary but motionless face.

Though he opted to use a Digispark, you should be able to use any Arduino that is small enough to stuff inside the plastic head. [Chuck] cut some holes in the eyeballs and glued in two RGB LEDs, then cobbled together a quick-and-dirty mount in the mouth area to hold a small servo. The lights and the servo are wired to the Digispark, which turns the lights on and instructs the servo to slam the ring against the door. It’s is battery powered and currently has only two settings: on or off. This should be good enough to scare the kids for this year, but [Chuck] has plans to add a much-needed motion sensor and sound via a Bluetooth connection. 

As simple as this build is, it could be just the thing to get you in the holiday spirit, or to introduce the young hacker in your home to the world of electronics and coding. Check out the short video of the doorknocker after the break, then swing by [Chuck’s] website for detailed build instructions and his Github for the source code. If you’re having trouble finding this doorknocker at Wal-Mart, [Chuck] recommends a similar one on Amazon. Don’t stop now! Make some Flickering Pumpkins too, or if you want a challenge, hack together your very own Pepper’s Ghost illusion.

Continue reading “Halloween Doorknocker Decoration Hack”

Arduino-based Enigma Replica Is Fully Functional

This open-source Enigma replica by the folks at [ST-Geotronics] is simply stunning. They drew their inspiration from a hilarious build we saw a few years ago that hacked a children’s toy into an Enigma machine. Their project is instead modeled on the original Enigma M4 cipher machine, and aside from a bit of artistic license, we think they nailed the visual style. As for functionality, the guide claims everything works, right down to the plugboard.

Rather than try to immediately cram everything into the final enclosure, the [ST-Geotronics] gang painstakingly worked out a prototype to be sure the four 16-segment LED displays had been wired correctly and functioned properly. The next step was laying out a swarm of buttons and resistors on a 6″x8″ perfboard. They used charlieplexing to handle the 16-segment displays (which actually have 17 LEDs each), and deceptively disguised each display as a nixie tube by mounting them vertically and encasing them in a transparent dome. The case follows the M4’s original dimensions and consists of a plywood box with scrap steel for the top plate.

Swing by their Instructables page for more details. There you can find several Arduino sketches to test functionality and the code for five different M4 operation modes.

LED Costumes And Clothing

3ledCostume

Our tips line recently received an influx of wearable LED projects, both for casual and professional wear. [Elizabeth] and [Luis] have created the Lüme wearable collection, aimed at accessorizing by adding adjustable accent colors to jackets, t-shirts and dresses. The electronics are custom-made, built around an ATMega32u4, and each is Bluetooth enabled to interact with a user’s cell phone. From the phone, you can change colors, sequences, set up events, and even take advantage of an “inkdropper-style” feature that matches the color of the LEDs to any object you point your camera at.

[Michal’s] project is an entire suit for a dance and laser show entitled “Tron Dance”, which uses several RGB LED strips placed on key points of the wearer’s costume. It looks like [Michal] has intentionally avoided the joint areas to prevent any problems with breaks or bends, but still manages to place enough to cover the entire body. We aren’t sure what controls everything, but you can watch it go through various sequences and survive an onstage performance after the break.

Finally, in yet another kind of performance, magician [Kiki Tay] has built a jacket that’s overflowing with RGB LEDs. [Kiki] wanted wearable LED control that could be used in various situations without having to re-invent the wheel each time, so he developed his own board — the LED Magician: an Arduino-compatible solution. The board has 12 outputs channels, drives 50+ LEDs per channel and features 12 on-board LEDs that display a preview of the output. To make interactions user-friendly, [Kiki] has provided 32 built-in sequences and adjustable speeds that the user can program via 4 buttons on the board. If that isn’t enough control, there are some options for external control as well. The jacket itself runs off a hobby LiPo battery and is blindingly bright: stick around after the break for a video.

Continue reading “LED Costumes And Clothing”