Herd Single Cell Organisms With Your Mind

May 23, 2013 by Mike Szczys 7 Comments

mind-controlled-paramecium

Most project tips involving brainwaves get passed over because it’s hard to make much out of that type of control. This project doesn’t necessarily make progress on the control side on this, but you have to admit that herding life forms with your thoughts deserves a closer look.

[Geva] set up a rig that allows him to interact with paramecium — tiny single cell organism that are happy to swim around all day long. Just like vertebrates they’re not big fans of electric shocks. Run some current through the fluid and they’ll swim toward the negative electrode.

This experiment uses four pencil leads as electrodes. These are driven by an Arduino which reacts to the input from a toy brain wave device. Concentrate in just the right way and they will swim wherever you will them to.

This isn’t quite as involved as cockroach mind control, but it’s every bit as interesting
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Listening To Aircraft Transponders With A Raspberry Pi

May 23, 2013 by Brian Benchoff 31 Comments

Last year’s big hack was software-defined radio; a small USB TV tuner that could listen in on radio broadcasts anywhere between 64 and 1200 MHz. This year, it’s all about the Raspberry Pi, so it’s surprising we’re only just now seeing a mashup of these two pieces of hardware. [Corq] is using a Raspi and RTLSDR TV tuner to listen in on aircraft transponders, and getting a whole bunch of data from aircraft flying overhead.

Even though the ADS-B decoder [Corq] is using is written for OS X, he’s reading the data coming from the USB TV tuner over the network with a program called Dump1090. This program allows [Corq] to attach his SDR to a Raspbery Pi and put it somewhere the antenna will get good reception – an attic, or an outdoor weatherproof case – and stream data to his desktop over a WiFi or network connection.

With a USB TV tuner and a Raspberry Pi, [Corq] is able read the tail numbers, altitude, latitude, longitude, speed, heading, and even the type of aircraft currently flying over his house. That’s cool enough, but the fact that he can effectively do this over the Internet makes it a brilliant hardware mashup.

Tracking Cicadas With Radiolab And An Arduino

May 23, 2013 by Brian Benchoff 27 Comments

Cicadia

Once every 17 years, a population of cicadas ranging from Connecticut to the Appalachian highlands of North Carolina emerges to annoy everyone within earshot. The last time east coasters saw this brood was in 1996, making 2013 yet another year of annoying insect pests. The only question is, when will we start to see this year’s cicada brood?

Radiolab, the awesome podcast and public radio show, has put together an awesome project that asks listeners to track when the cicadas in their area will emerge. Cicadas generally enter their loud and obnoxious adult stage when the ground temperature 8 inches below the surface reaches 64º F. Armed with an Arduino, thermistor, and a few wires and resistors, any Radiolab listener can upload soil temperature data to Radiolab servers where all the data will be correlated with documented cicada sightings.

After following the page’s instructions for wiring up a bunch of LEDs and a thermistor to an Arduino, just upload the most well-commented code we’ve ever seen and go outside to take soil temperature measurements. The temperature is displayed in a pseudo-binary format on nine LEDs. To decode the temperature without counting by powers of two, Radiolab has an online decoder that also allows you to upload your data and location.

LED Etch-a-Sketch Built Without A Microcontroller

May 23, 2013 by Mike Szczys 21 Comments

logic-etch-a-sketch

This project is a wonderful example of what can be accomplished with a rather complicated logic circuit. It’s an Etch-a-Sketch made from a 16×16 LED grid. That in itself is only somewhat interesting. But when hearing about the features and that it is driven by logic chips we were unable to dream up how it was designed. There’s no schematic but the video commentary explains all.

The thing that confused us the most is that the cursor is shining brighter than the rest of the pixels. This is done with two different 555 times and a duty cycle trick. When you turn the trimpots the cursor position is tracked by some decade counters. Pixels in your path are written to a RAM chip which acts as the frame buffer. And there’s even a level conversion hack that let’s the display run at 15v to achieve the desired brightness. Top notch!
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Ask Hackaday: What Are We Going To Do With The New Kinect?

May 22, 2013 by Brian Benchoff 60 Comments

kinect

Yesterday Microsoft announced their new cable box, the Xbox One. Included in the announcement is a vastly improved Kinect sensor. It won’t be available until next Christmas, but now the question is what are we going to do with it?

From what initial specs that can be found, the new version of the Kinect will output RGB 1080p video over a USB 3.0 connection to the new Xbox. The IR depth camera of the original Kinect has been replaced with a time of flight camera – a camera that is able to send out a pulse of light and time how long it takes for photons to be reflected back to the camera. While there have been some inroads into making low-cost ToF cameras – namely Intel and Creative’s Interactive Gesture Camera Development Kit and the $250 DepthSense 325 from SoftKinetic – the Kinect 2.0 will be the first time of flight camera you’ll be able to buy for a few hundred bucks at any Walmart.

We’ve seen a ton of awesome Kinect hacks over the years. Everything from a ‘holographic display’ that turns any TV into a 3D display, computer vision for robots, and a 3D scanner among others. A new Kinect sensor with better 3D resolution can only improve existing projects and the time of flight sensor – like the one found in Google’s driverless car – opens up the door for a whole bunch of new projects.

So, readers of Hackaday, assuming someone can write a driver in a few days like the Kinect 1.0, what are we going to do with it?

While we’re at it, keep in mind we made a call for Wii U controller hacks. If somebody can crack that nut, it’ll be an awesome remote for robots and FPV airplanes and drones.

Anti-Tetris Project Is A Study In Hand Tracking

May 22, 2013 by Mike Szczys 6 Comments

anti-tetris

The game of Anti-Tetris is played by standing in front of a monitor and watch falling Tetris pieces overlaid on a video image of your body. Each hand is used to make pieces disappear so that they don’t stack up to the top of the screen. We don’t see this as the next big indie game. What we do see are some very interesting techniques for hand tracking.

An FPGA drives the game, using a camera as input. To track your hands the Cornell students figured out that YUV images show a specific range of skin tones which can be coded as a filter to direct cursor placement. But they needed a bit of a hack to get at those values. They patched into the camera circuit before the YUV is converted to RGB for the NTSC output.

Registering hand movement perpendicular to the screen is also a challenge that they faced. Because the hand location has already been established they were able to measure distance between the upper and lower boundaries. If that distance changes fast enough it is treated as an input, making the current block disappear.

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