Hackaday Prize Entry: Hands|On Gloves Speaks Sign Language

October 11, 2016 by Elliot Williams 7 Comments

The Hands|On glove looks like it’s a PowerGlove replacement, but it’s a lot more and a lot better. (Which is not to say that the Power Glove wasn’t cool. It was bad.) And it has to be — the task that it’s tackling isn’t playing stripped-down video games, but instead reading out loud the user’s sign-language gestures so that people who don’t understand sign can understand those who do.

The glove needs a lot of sensor data to accurately interpret the user’s gestures, and the Hands|On doesn’t disappoint. Multiple flex sensors are attached to each finger, so that the glove can tell which joints are bent. Some fingers have capacitive touch pads on them so that the glove can know when two fingers are touching each other, which is important in the US sign alphabet. Finally, the glove has a nine degree-of-freedom inertial measurement unit (IMU) so that it can keep track of pitch, yaw, and roll as well as the hand’s orientation.

In short, the glove takes in a lot of data. This data is cleaned up and analyzed in a Teensy 3.2 board, and sent off over Bluetooth to its final destination. There’s a lot of work done (and some still to be done) on the software side as well. Have a read through the project’s report (PDF) if you’re interested in support vector machines for sign classification.

Sign language is most deaf folks’ native language, and it’s a shame that the hearing community can’t understand it directly. Breaking down that barrier is a great idea, and it makes a great entry in the Hackaday Prize!

Two Words That Don’t Mean What You Think They Do

October 9, 2016 by Elliot Williams 23 Comments

When you hear “gravity waves” or “sprites”, you’d think you would know what is being discussed. After all, those ripples in space-time that Einstein predicted would emanate from twin, colliding, black holes were recently observed to much fanfare. And who doesn’t love early 8-bit computer animations? So when we were browsing over at SpaceWeather we were shocked to find that we were wrong twice, in one photo (on the right). Continue reading “Two Words That Don’t Mean What You Think They Do” →

Minimal Computer And Operating System: One Button, One LED

October 8, 2016 by Elliot Williams 15 Comments

DUO BINARY is a very, very small computer system in every possible sense. It runs on an ATtiny84, which has even got “tiny” in its name. The user interface is a single button for data entry and a single LED for feedback, making this binary keyboard look frivolously over-complicated. It uses a devilish chimera of Morse code and a truncated ASCII to enter data, and the LED blinks the same back at you.

We’re guessing that [Jack Eisenmann] is the only person in the world who can control this thing, and you can watch him doing so in the video embedded below. Continue reading “Minimal Computer And Operating System: One Button, One LED” →

NASA Knows Where The Meteors Are

October 8, 2016 by Elliot Williams 30 Comments

NASA has been tracking bright meteoroids (“fireballs”) using a distributed network of video cameras pointed upwards. And while we usually think of NASA in the context of multi-bazillion dollar rocket ships, but this operation is clearly shoe-string. This is a hack worthy of Hackaday.

The basic idea is that with many wide-angle video cameras capturing the night sky, and a little bit of image processing, identifying meteoroids in the night sky should be fairly easy. When enough cameras capture the same meteoroid, one can use triangulation to back out the path of the meteoroid in 3D, estimate its mass, and more. It’s surprising how many there are to see on any given night.

You can watch the videos of a meteoroid event from any camera, watch the cameras live, and even download the meteoroid’s orbital parameters. We’re bookmarking this website for the next big meteor shower.

The work is apparently based on [Rob Weryk]’s ASGARD system, for which the code is unfortunately unavailable. But it shouldn’t be all that hard to hack something together with a single-board computer, camera, and OpenCV. NASA’s project is limited to the US so far, but we wonder how much more data could be collected with a network of cameras all over the globe. So which ones of you are going to take up our challenge? Build your own version and let us know about it!

Between this project and the Radio Meteor Zoo, we’re surprised at how much public information there is out there about the rocky balls of fire that rain down on us every night, and will eventually be responsible for our extinction. At least we can be sure we’ll get it on film.

Blue LED Streetlights Keeping You Awake?

October 7, 2016 by Elliot Williams 78 Comments

If you’ve played around with “white” LEDs, you already know that there’s no such thing. There’s warm white and cool white and any numbers of whites in-between. And when white LEDs were new, the bluer “cool white” variety were significantly more prevalent.

Enough US states have swapped out their old street lights with LEDs that it may be having a measurable effect on people and on the animals around us. This is the claim in a recent position paper by the American Medical Association’s Council on Science and Public Health. (Report as PDF.)

Science strongly suggests that heavy doses of light can keep people from falling asleep, and that brighter LED streetlamps may be making the problem worse. The AMA report goes a step further, and pins extra blame on the color of the light. Blue light apparently suppresses the production of melatonin which helps you sleep at night. And it’s not just humans whose circadian rhythms are getting messed up — the effects are seen throughout the animal kingdom.

Continue reading “Blue LED Streetlights Keeping You Awake?” →

Tetris In 446 Bytes

October 6, 2016 by Elliot Williams 48 Comments

You want to play Tetris. You want to play Tetris on any operating system. You want to play on an old IBM PC, you want to play Tetris on a new MacBook. You want a Tetris that’ll fit inside the master boot record of a disk. You want Tetris as an operating system. You want TetrOS.

Or maybe you don’t, but it’s a fantastic piece of work, and we love tiny demos. Check it out below the break. Or read through the source code in the banner image.

Continue reading “Tetris In 446 Bytes” →

Driving 16 WS2812B Strips With GPIOs And DMA

October 6, 2016 by Elliot Williams 8 Comments

[Martin Hubáček] wrote in with his WS2812 LED library for the STM32F3 series processors. [Martin]’s library takes the same approach as [Paul Stoffregen]’s OctoWS2811 for the Teensy, and [Erich Styger]’s for the Freescale FRDM-K64F board. That is, it uses three DMA channels to get the signal out as fast as possible.

Continue reading “Driving 16 WS2812B Strips With GPIOs And DMA” →