Hack a Day

Last week we saw [Todd]‘s solution to getting a tripod out-of-the-way when filming a few DIY videos. It’s an overhead camera gantry that allows him to move a camera around his garage workshop without a tripod getting in the way. This weekend, he’s back with a new and improved version. It’s a vast improvement over his Mk 1 gantry system, and it much simpler to build, to boot.

[Todd]‘s new and improved overhead camera gantry builds is a vast improvement on his previous build. In the original build, [Todd] used only one cross piece between the overhead garage door tracks, and the carriage suspending the tripod overhead was extremely clunky.

Version 2 of [Todd]‘s camera gantry again makes use of unused garage door tracks to suspend a tripod above his workshop. This time, though, he’s using two rails between these garage door tracks making pushing the tripod around his workshop much easier – even when not pushing it from the middle.

To move the camera across the workspace, [Todd] did away with the square tube between the garage door tracks and used another set of garage door tracks. It’s a beautiful system that moves very, very smoothly between his workbench and welding station, perfect for making a few high-quality DIY videos.

You can check out [Todd]‘s build video after the break.

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The Raspberry Pi is an excellent tool to build the ‘Internet of things’ we’ve been hearing about, but there’s still the issue of connecting the Raspi to other devices. The EVE Alpha – a breakout board for several wireless radio modules for the Raspberry Pi – hopes to change that with their Kickstarter campaign.

The idea behind the EVE is to provide a link between low-power radio modules found in a few of the microcontroller projects we’ve seen and the Raspberry Pi. It does this by simply serving as a breakout board, taking the GPIO pins on the Raspi and connecting them to solder pads for a few of the many radio modules currently available.

Already the EVE supports the RFM12B wireless tranciever, a Z-Wave module, 868-915Mhz SRF modules, and has a breakout for an XBee module, allowing the EVE to communicate using one of the many different XBee boards. There’s also a battery-backed real-time clock and temperature sensor thrown in for good measure making this board the perfect building block for an outdoor weather station or solar array.

It’s an awesome idea, and if you already have a few radio modules, incredibly cheap; just the PCB is only £6, and a board with all the SMD components is only £20.

In case you’ve been living under a rock for the past few months, Nintendo will be releasing their next-gen console this weekend. It’s called the Wii U, and one of the most interesting features is the Wii U GamePad – the first controller to feature a full-color video screen right between the analog sticks.

Needless to say, we’re not terribly interested in the Wii U. The GamePad, though, looks perfect for robot controllers, FPV aerial vehicles, and a whole slew of projects that require some remote control.

The hardware for the GamePad is fairly impressive; apart from D pads and analog sticks, the new Wii Controller features a front-facing camera, gyroscope, accelerometer, magnetometer, 6.2 inch 854×480 touchscreen display, and an extension port housing an I2C bus for all your old Wii peripherals.

Other than a stock feature list, we have no idea how the Wii U will be able to transmit video to the GamePad. It might be WiFi, allowing you to connect all your projects to a wireless network and control them without a whole lot of hardware.

We’ll keep you posted on the developments of hacking the Wii U GamePad. Hopefully we’ll all have an awesome remote control by next year.

Forever.fm is [Peter]‘s combination of SoundCloud and The Echo Nest that plays a continuous stream of beat-matched music. The result is a web radio station that just keeps playing.

[Peter] provided a great write up on how he built the app. The server side is Python, using the Tornado web server and Tornadio2 + Socket.IO for handling live updates in the client. To deal with the challenge of streaming audio, he wrote a LAME interface for Python that handles encoding the raw, beat-matched audio into MP3 blocks. These blocks are queued up and sent out to the client by the web server.

Another challenge was choosing songs. Forever.fm takes the “hottest” songs from SoundCloud and creates a graph. Then it finds the shortest path to traverse the entire graph: a Travelling Salesman Problem. The solution used by Forever.fm finds an iterative approximation, then uses that to make a list of tracks. Of course, the resulting music is going to be whatever’s hot on SoundCloud. This may, or may not, match your personal tastes.

There’s a lot of neat stuff here, and [Peter] has open-sourced the code on his github if you’re interested in checking out the details.

When we decided that our template needed a remake several years ago, we knew it was going to be a long and difficult process. We offered you a chance to give us some input in a recent post and now we are releasing the first iteration of the new template.

For those that saw the mockups and gave us your opinion, you will be happy to see we actually listened to many thoughts and incorporated them in our final design.  We worked with some people at Google to determine what features should be tossed and what to keep, and what we have ended up with, is what you see. We also acknowledge that not everyone will love the change, but we feel it is a move in the right direction. We’re really happy how it has ended up.

I want to offer a special thanks to [Stephanie Froehner] who put tons of time into making this template pretty, even if it has been hacked and slashed a bit since then.

Join me after the break for an explanation of some of the new features and upcoming features.

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This is an x-ray detector built by [Ben Krasnow]. It’s an interesting combination of parts working with an oscilloscope. The result is an audible clicking much the same as you would hear from a Geiger counter

He’s measuring backscatter, which is the reflection of x-rays on other objects. Because the signal will be quite weak compared to waves emitted directly from an x-ray source he needed a large collector to measure them. He started by gutting an x-ray image intensifying cassette. This has a phosphor layer that glows when excited by x-rays. The idea is that the glowing phosphors do a better job of exposing film than direct x-rays can. But [Ben's] not using film. He built that pyramid-shaped collector with the phosphor material as the base. At the apex of the pyramid he mounted a photomultiplier tube (repurposed from his scanning electron microscope) which can detect the excited points on its surface. His oscilloscope monitors the PMT, then issues a voltage spike on the calibration connector which is being fed to an audio amplifier. Don’t miss his presentation embedded after the break.

[Ben] mentions that this build is in preparation for a future project. We’d love to hear what you think he’s working on. Leave your guess in the comments section.

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