Arduino | Raspberry Pi

Kegerface – for all your beer stocking needs

Kegerface is a digital tap list display from SchrodingersDrunk, which you can read more about over on Reddit. It’s an interface for a Kegerator, hence the name. I had to look that up – a Kegerator is a device for dispensing draught beer in the home, involving all kinds of kit like a fridge and a tank full of carbon dioxide. In the picture below, it’s the thing with the spigots sticking out of it.

We, of course, are interested in what’s going on above the spigots.

Click to embiggen

The back-end here is some PHP which interprets data from a shared Google spreadsheet. The whole thing runs off a Raspberry Pi that’s attached to the back of the display. All the information you need is here: the type of beer, the ABV, the hoppiness (scored out of three – that’s what the green glyphs represent), the maker, and, most importantly, how much you have left.

You can find SchrodingersDrunk’s code, along with assets like those hop graphics on Github. The Kegerface is under a CC licence, and other Kegerator owners have been modifying the setup for their own use.

Andy Davies has done a lot of work on his own version. He’s tweaked the interface, and added the bar temperature and a breakdown of how many pints are left in stock; he’s also using MySQL rather than going the CSV/PHP route.

Compare with the interface above, and spot the differences! (Click to enlarge.) We deplore your taste in ginger beer, Andy. Hollows & Fentimans’ hard stuff is much nicer.

Andy’s also made the Kegerface work for bottled beer as well as draught beers, and best of all, has made stock updating easier by attaching an RFID reader to an Arduino, which is then hooked up to the Pi. So every time you take a bottle, you swipe the attached RFID tag across the bar, and the stock is adjusted on the Kegerface. Again, everything’s on GitHub if you want to try building one yourself.

I’m trying to work out whether it’s legal for us to get one of these for the office.

Recantha’s only gone and made a tricorder.

I’ve been waiting for…ooh, just over a year, for someone to do this. Recantha, an old hand here in the comments and on the forums, has built a tricorder.

There surely can’t be anyone here without a passing familiarity with Star Trek, but just in case: the tricorder is a made-up thing used by the crew of the Enterprise to measure stuff, store data and scout ahead remotely when exploring strange new worlds, seeking out new life and new civilisations, and all that jazz. Despite its made-up-ness, the tricorder remains a terribly desirable thing. I’ve always wanted to be able to tell whether my planet is M-class or not.

Recantha has bodged together his home-made tricorder using a Pi, some sensors (two for temperature, and one each for magnetism and distance), an LCD display, some switches, a light-resistant resistor, a thermistor and an Arduino Leonardo clone. We hope he keeps adding sensors to it, and maybe, later on, a camera board, until he runs out of space. How about a Geiger counter (this one already works with the Pi)?

Here’s a spot of video explaining what everything on the Picorder does:

(Best of all, the whole thing is cased in LEGO.)

And here’s some more video, showing the thing in action.

If you’re interested in reproducing or building on this project, Recantha’s blogged about it (he has an excellent website, all about Raspberry Pi), and has left a guide to the project over at Pideas, the new site for collecting Raspberry Pi projects. (Go and add something of your own!) Thanks very much for this, Recantha; our office costume parties will now have a dash of added realism. Jamesh has drawn the short straw and will be dressed as Nog.

Some Christmas lights projects

I haven’t even put my tree up yet, but lots of you have been very busy with the Christmas decorations and your Raspberry Pis. Here are some projects you’ve still got time to emulate before Santa comes.

ConsiderIT.co.uk take the whole Internet of Things idea seriously, and have wired up their office with a positive welter of fairy lights and a networked Raspberry Pi. They invite you to come and turn the lights on and off, watching the torment of their employees over a live feed. I took this screengrab from the feed from their office yesterday, and I don’t know whether to feel deep pride or terrible, terrible shame over the fact that these poor people are being subjected to this visual horror in their office courtesy of a Raspberry Pi. Nice job with the hats, guys.

A quiet moment. You should visit the site (click the image) – pretty much everything in that room has something you can make flash attached to it.

If you aren’t a sadist wanting to inflict misery and migraines on the working day of three people in a tiny room, but still want to turn some lights on and off, there’s a similar setup in a UK living room, where tree lights can be turned on and off, which was highlighted in this month’s MagPi. (The tree is turn-on-and-offable in the daytime too, but it’s much more fun at night.)

A screen grab from the live feed. This is a gentler, less guilt-inducing scene than making someone’s office flash: but you can still make these lights blink on and off like the dickens. Click the image to visit the site.

If you’re looking to do something a little less flashy, but still useful, here’s an easy one, which I found linked to from our forums. This timer turns your outdoor lights on and off according to the local sunset and sunrise times. Outside the holiday season, there are plenty of other applications you could use this setup for. You can find software and a shopping list for the hardware you’ll need, alongside helpful diagrams and photos to get you set up, at Savage Home Automation.

A very easy piece of GPIO wiring! Click the image to read more.

Finally, I found this lovely little decoration on Flickr. And assumed it was the sort of thing you buy for vast sums in expensive home interiors shops. But no! It’s a Raspberry Pi hack – just one with fewer protruding wires than we’re used to seeing. This gorgeous little object from Rumtopf (who has some other amazing projects in his Flickr stream - the candy cane and cookie windmill that powers LEDs is my current favourite) incorporates Cheerlights, which are synchronised with other Cheerlights all over the world according to social networking trends. There’s an Arduino and an XBee radio in the box, talking wirelessly to a Raspberry Pi in another room.

Rumtopf: you should sell these. You’d make a mint. (And I want one!)

Rumtopf has made code for making your own available at Github. Let us know if you make something similar yourselves!

Pumpkin Pi

We’re on the hunt for guest posts for a couple of weeks in November. See this post for more details on how to contribute.

There seem to be a lot of Raspberry Pi + pumpkin projects around at the moment. Can’t think why.

Gordon@Drogon’s Pumpkin Pi (as featured in the MagPi). Gordon had to photograph this in the summer, when pumpkins were not available, so he’s used a sort of Halloween bucket instead. Click the picture for instructions and more bucket photos.

There’s non-pumpkin spooky activity out there too. I love this: it’s a Raspberry Pi, an eight-switch relay, a garage door lifter rod, and a can opener, all hacked together to make a candy dispensing machine so you don’t actually have to interact with any children or open the front door on Halloween.

I love this even more: it’s a Raspberry Pi and a Makey Makey in a box, hooked together to make a Halloween sound box that uses the conductivity of your fingers to trigger events.

And Shawn Wallace at Make has made this, with an Arduino, a Pi, some switches and a recording of the Wilhelm Scream. Visit Make for complete instructions on making your own.

Do you have any Halloween Pi plans? Let us know in the comments.

BrewPi

In keeping with our educational mission, here’s a post about beer.

There seems to be a surprising overlap (perhaps it’s not so surprising) between the maker/hacker community and the home brew community. We are aware of a few small commercial breweries who are already using Raspberry Pis to drive automation of things like pressure and mash temperature, but until now everybody brewing with a Pi has had to come up with their own solutions.

Until now, that is. Elco, a beer and Pi enthusiast, has produced an open-source fermentation controller for the Raspberry Pi and an Arduino which is available for the whole community to use. (Those of you over legal drinking age, that is.) BrewPi allows you to control the process through a web browser interface. It’s completely user-configurable, will control temperature to within 0.1 degrees Celsius – and it outputs helpful graphs. (We like graphs.)

BrewPi user interface – lots of lovely, lovely graphs. Click to embiggen.

Elco’s currently working a digital specific gravity sensor (which at its current stage of development has to do with a weight dangling from a string), and he’s looking for community help with the continued development of BrewPi. Head over to his website, help out with the codebase and contribute to his wiki – and let us know if you end up using the software to do any brewing yourselves.

Raspberry Pi and Arduino

We’ve been a bit sad to see some people who are very passionate about the Arduino community coming down quite hard on the Raspberry Pi project as the Big Bad, suggesting that we’re trying to encroach on Arduino’s territory and offering unfair competition. It’s really not the case; we think Arduino is a marvellous thing, and we don’t feel the two are comparable – you’ll be using them for different things. Arduino uses a microcontroller; Raspberry Pi uses an applications processor. There are some things a Raspberry Pi is better for (you can hook a Raspi up to a TV, for example), and loads of things an Arduino is more suited to. But we feel very strongly that there’s a good potential marriage between the Arduinos you might have in your drawer at home, and your Raspberry Pi, which you can use to drive them. And it looks like we’re not the only people to come to that conclusion.

Picture stolen from Simon Monk. Thanks Simon!

Simon Monk has been getting his Raspberry Pi and Arduino talking using Python. There are instructions on his blog, which seasoned Arduino hackers should find easy enough to follow.

Meanwhile, Omer is working on a new device called Ponte, which acts as a bridge between Raspberry Pi and Arduino or its shields. You can either use it as a link between your Arduino and your Raspberry Pi, or use it to connect Arduino shields directly to your Raspi. This is incredibly exciting for us, given the enormous range of shields that are out there in the ecosystem already (I think the number stands at about 280 at the moment). It’s currently in development, and it’ll be open hardware when he’s done with it. Prototype schematics and layout are on his website already; do go and have a look.

Ultimately, we hope that successful sales of Raspberry Pi will encourage people to buy Arduinos too, and vice versa: the two have what I believe business school-types call “good synergy”. (I’m making choking noises. I do not like that term at all.) So here’s to a happy partnership between the two boards – I hope they’ll be good friends!