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Guest post from Khan Academy Lite

Update: KA Lite dropped us a line to let us know they had a newer version of today’s post ready for us this evening, that they’d prefer us to use. The updated version is below. Enjoy!

Liz: We’ve been talking a bit about Khan Academy Lite on this blog recently. KA Lite is the offline version of Khan Academy, and we’ve recently seen the Kingdom of Bhutan’s first Raspberry Pi being used as a server to give kids offline access to the huge, free suite of Khan Academy’s top-quality video lectures and learning materials. You can read more about Khan Academy on their own website, but don’t just take their word for it: there’s a wealth of material online about the Khan Academy learning experience from users, if you have a few minutes to google for it.

The KA Lite team recently incorporated as a California-based nonprofit organization: Foundation for Learning Equality. They are dedicated to creating tools for the sharing and creation of open-licensed educational content for use by anyone around the world, with special emphasis on reaching the 65% of the world that does not have Internet access, and those with limited-bandwidth, expensive, or unreliable connections.

The KA Lite project emerged during a development internship at Khan Academy in the summer of 2012. Having just received their first eagerly awaited Raspberry Pi, a couple of interns decided to try porting Khan Academy’s educational materials for use on the Raspberry Pi. As a low power device that can run off batteries, solar, or a generator, and its ability to use existing hardware for output (such as old televisions), it is an ideal platform for distributing content to the developing world. After working on “Khanberry Pi” for several weeks, a very simple static file-based version that worked on the Raspberry Pi was presented at a Khan Academy company event in August. The overwhelming enthusiasm about its potential impact led to further brainstorming, while conversations with other organizations using Khan Academy in the developing world reinforced the strong need for a more general software platform for deploying Khan Academy content in offline contexts.

Following brainstorming and feedback from organizations, the design specifications shifted towards a platform that could run on any operating system, on any low-powered hardware (with the Raspberry Pi as an exemplar device), and with mechanisms in place to synchronize data and share new content through any existing channels. Development then began, outside regular working hours, on what became KA Lite, a standalone dynamic web platform that was demoed to Khan Academy at the end of the summer internships in September. In the fall quarter, at UC San Diego, a team of passionate undergraduates, joined later by graduate students, jumped on board to apply their development, design, and user experience skills to build out and improve the platform. In December of 2012, the KA Lite team first announced the open-source project publicly on popular developer channels, and developers around the world soon began contributing and collaborating on the development process, while teachers and organizations in many countries started testing out deployments with their students.

The Raspberry Pi was not only the original inspiration behind the KA Lite project, but continues to be the most cost-effective way to deploy the platform to areas without existing infrastructure. While we had originally envisioned the Pi primarily as a client device, it has proven itself to be an ideal server platform for bringing KA Lite to offline communities. With the addition of a cheap wifi dongle, and a bit of software setup, the Pi is transformed into a standalone wifi access point that can serve up a dynamic web interface to nearby client devices, without the need for internet.

We were unable to swamp the Pi server or its wireless connection even with 35 tablets connecting to it simultaneously.

Inexpensive Android devices, which have been proliferating through the developing world, serve as excellent client devices to connect to a Pi access point. How does the Pi hold up to the task of serving a classroom full of tablet users over a single wifi dongle? We had been warned that a small number of wifi clients would likely swamp the connection, so last week we put it to the test. The Raspberry Pi/Wi-Pi combo held up smoothly, with 35 tablets simultaneously navigating through the KA Lite web interface and streaming Khan Academy videos.

We’re experimenting with alternate power sources, such as the solar-charged d.light that is already in wide distribution through the developing world. The Pi’s low power requirements make this a breeze.

If you’re interested in helping to develop KA Lite or want to deploy it with your students, check out the KA Lite Wiki for more information on how to get involved!

Raspberry Pi, for all your 50s diner needs

Have you ever been to a cafe or restaurant with 1950s jukebox wallboxes in each booth? Wallboxes were an extension for a jukebox, making it more convenient to select music right from your table. You’d drop a coin in, choose a song from the flipbook behind the glass, chrome and plastics, and the machine would send pulses down a wire to the restaurant’s jukebox, where a stepper would decode the pulses and queue up the song you’d picked. Refurbished wallboxes occasionally pop up in mock-50s diners; you’ll also see them for sale on eBay for anything up to a few hundred quid, and people buy them to add to their jukeboxes, or just as home decoration (I’ve seen one being used as a particularly cumbersome phonebook).

Wallbox in situ

Steve Devlin bought himself a couple of wallboxes a few years ago, meaning to hook them up to an MP3 player. He then switched over to a SONOS wireless media system in his house, and forgot about the wallboxes for a couple of years.

Enter the Pi.

On looking at a Raspberry Pi and a wallbox, Steve had an idea. Why not hook the two up together to make a controller for the SONOS system? The Pi decodes the pulses from the box, and sends the information to the SONOS system. (This approach will work with any UPnP protocol, so you’re not limited to using SONOS.)

Steve’s thinking about further customisation: a strip in the box with Radio 4 on it; some dynamic strips like “songs of the week”, which will play a selection of the week’s most-played tunes; some LEDs to show a binary index of common faults, like the wifi being down, or a song not being found.

There are full instructions and much more information on Steve’s website. We think there’s something really compelling about this mix of old and new; thanks for sharing, Steve!

MAKE and MCM Raspberry Pi Design Competition: the winners!

MAKE held a Raspberry Pi Design competition with MCM Electronics for US-based Pi owners, and have just released the results. I’m not sure what’s more impressive: the outstanding quality of the entries, or the fact that even though we spend much of the day furiously googling for new Pi projects, many of the submissions were new to us here at the Foundation. It’s great for us to watch other organisations running contests like this: not least because it’s a real relief not to have to judge them ourselves!

The Grand Prize went to Intonarumori, a collection of magic sound boxes made by a hacker/art collective called urbanSTEW. The STEW-folk say:

Intonarumori is a series of interactive sound boxes created by an art/tech collective, urbanSTEW. The project is based on a century-old futurist movement in which noise-generating machines were created. Inspired by this, urbanSTEW built six new noise machines, each equipped with a Raspberry Pi and various sensors/controls. The boxes are self contained and only need to be plugged in. Intonarumori was presented at a creativity festival where they were played by over 2,000 children/adults.

The Sunlight Foundation’s Lobbyist Meter won the Artistic category: we tweeted about this a while back (and it’s been in my “things to blog” folder for a while) because we thought it was a clever, snarky, funny way to bring attention to a very serious issue. You can read more about the Lobbyist Meter on the Sunlight Foundation’s website. Here it is, doing its transparent, democratic thing.

The Education category award went to a project you’ll all have seen before, if you’re regular readers: Emma Bennett’s beautiful school State Board project (which we have been using in talks as a demonstration of some of the very cool stuff we see kids doing with the Pi) won the prize. Read more about it in the post we wrote when we first saw Emma’s work, and see some video of the board in action below.

Everybody in our offices secretly wants a wooden case for their Pi, because we are all impractical, and we have all read Idoru. The Enclosures category was won by Chris Crumpacker for this beautiful piece of hand-tooled walnut. Chris, if you’re reading, please get in touch. We absolutely, positively need one of these to hold one of the Pis at Raspberry Towers.

Chris told MAKE:

Some times all you need is a bit of scrap wood for inspiration. I had some walnut left over from a previous project. I just love the look of walnut. I had seen other wood cases but they where always 6 pieces of wood glued or nailed together to make a box. I wanted it to be one hunk of wood and my intentions were to carve out a home for the Raspberry Pi.

The final category, Utility, was won by another project we’ve featured here: David Bryan’s cat feeder, which I enjoyed blogging about because it gave me the opportunity to use the phrase “liver-flavoured kibbles”.

Congratulations to all the winners, and thanks to MAKE and MCM for running the competition. You can see the other entries on MAKE’s website – enjoy!

Rob, Bacon

Our very own Justin Bieber, Rob Bishop, was at the world’s best-named conference last week. Bacon (www.devslovebacon.com) is a London conference on things developers love, like Raspberry Pi, Go, rockets, close-up magic…and preserved meats. The video of his talk was just released yesterday. Rob says, on watching it: “Man, I need a haircut.”

Rob’s good at this stuff, isn’t he?

The Raspberry Pi in scientific research

The cost implications that come with finding yourself able to buy a computer for $25 are significant for all of us, but they can make a real difference to the way cash-strapped researchers do things. We’re seeing a surprising number of university departments around the world using the Pi for the sort of tasks you’d previously have pointed a PC at, with very gratifying results.

I had email from Lorna, who manages some of our social media, about a video she’d been sent yesterday. “It’s about crabs,” she said. “The seaside kind.” (Just as well, or I wouldn’t have been able to publish it.) David Soriano, who is an Associate Professor of Chemistry at the University of Pittsburgh-Bradford, has been using a webcam controlled by a Pi to monitor fiddler crabs which are being offered thermal polypeptides, rich in the amino acid tyrosine. Tyrosine starts the pathway to melanin pigment production in the crab, and David’s watching for colour changes that result from it. This is a long video, at 15 minutes, but it’s very interesting, as David describes the setup and some of the crabs’ behaviour.

David is also studying the effects of certain chemical agents on the American Cockroach with the help of a Pi. Cockroaches are much less cute than fiddler crabs, so I won’t embed the video here, but you can watch it on YouTube.

Meanwhile, over in France at Aix-Marseille Université, Sebastiaan Mathôt, a post-doc at the Laboratoire de Psychologie Cognitive, has been running his graphical experiment builder, OpenSesame, on the Pi.

Eben took part in a university psychology experiment once. The results, somewhat surprisingly, demonstrated that he had a closer relationship with Superman than he did with God.

Sebastiaan is testing the Pi for use in psychological experiments, and has found it very suitable. He found a few milliseconds’ inaccuracy in some measurements, but says:

If I were to set up a low-budget lab, I wouldn’t have any problem with running my behavioral studies on a Pi, since this type of temporal jitter has a negligible impact on statistical power.

You can find out more about the setup on his blog; it’s well worth a read.

The biologists are in on it too: click the picture below to visit the University of St Andrews in Scotland, whose Centre for Biological Diversity have written a Raspberry Pi phylogeny reconstruction program, so students can look at the relationship between phylogeny and evolution on a Pi.

Daniel Barker, from St Andrews, said:

Given a bunch of DNA sequences and some pre-processing, LVB gives you an idea how they are related. If you give it one sequence per species, it gives you an idea of how the species are related. LVB combines an optimality criterion that’s rapid to evaluate and a subtle heuristic search – with the intention of working fast, and reasonably well, with large input.

If you’d like to learn more (undergrad-level biology is a whole new world to a lot of us), Daniel came and posted some more explanation on our forums last year. Come and take a look.

Of course, you don’t need to be at a university to use a Pi to research something. Yesterday I spotted a brand new Twitter feed, fully automated with a Pi, dedicated to capturing an image of the Beijing sky every 15 minutes. Zhe Wu, who works at delicious.com, is collecting the visual data and will be using it to analyse changes in the condition of the city’s air. There’s not a lot of data to process yet; the images only started being collected yesterday. But we’re looking forward to seeing what he does with them. You can view the stream of pictures on Twitter.

Pictures of the Beijing sky today. It’s looking a bit less smoggy today than it did on my last trip!

Back in the UK, we’re seeing some pretty extraordinary research work coming out of schools too. The winners of the 16-18 section of the recent PA Consulting Awards competition, challenging schoolchildren to “make the world a better place” with a Pi, were Alyssa Dayan and Tom Hartley from Westminster School, whose Air Pi we’ve mentioned here before briefly; it’s a very sophisticated, very well implemented project we thought we should talk about some more.

Air Pi is, say Alyssa and Tom, “an automatic air quality & weather monitoring device powered by a Raspberry Pi, capable of displaying, recording and uploading information about temperature, humidity, air pressure, light levels, UV levels, carbon monoxide, nitrogen dioxide and smoke level to the internet.” It’s cheap, it’s modular, it’s open: we love it. Here are Alyssa and Tom, who will explain a bit more about the project and what’s being done with it.

There’s a lot more information on the AirPi website – head over and have a look. You can set one up yourself for as little as £50 (including the Pi), and AirPis are already being used to monitor air quality as far away as India.

Are you using a Pi for research? Let us know in the comments.

University of Cambridge Computer Lab 75th anniversary

We’re celebrating today: it’s the 75th anniversary of the University of Cambridge’s Computer Laboratory. From its beginnings in 1938 as the Mathematical Laboratory, it’s provided the foundations for much of our computing history; Raspberry Pi is only one of hundreds of successful business set up by academics and alumni, and we’re very proud to be associated with the Lab.

The old Mathematical Lab, on the New Museums Site in the centre of Cambridge

The University of Cambridge Computer Lab today: the William Gates Building.

Things have changed in computing since the Mathematical Laboratory’s early days. Just before our wedding, when Eben was writing up his PhD and we were living in university housing, the wife of a very old, very decorated gentlemen took me by the elbow with startlingly strong fingers after a dinner, and proffered a dire warning.

“You need to understand that life will not be easy if you marry a computer scientist, especially early in your marriage; you won’t always come first. When we were young marrieds, John would disappear for hours in the middle of the night to cool that damned machine for his supervisor.”

It turns out that “that damned machine” was EDSAC. (My advice to “young marrieds”: if you can’t beat them, join them.)

EDSAC1 in the 1940s, with Maurice Wilkes and William Renwick.

It’s thanks to work done in that laboratory that you’re holding a Raspberry Pi now that doesn’t need cooling at all, let alone in the middle of the night; ARM, whose technology is in the Pi’s processor, was originally a spinoff from the Computer Lab.

The Lab’s anniversary announcement says:

It was where EDSAC, the first programmable computer ever brought into general service, was built, and where microprogramming was pioneered by Maurice Wilkes, the Lab’s second Director, using EDSAC 2. Towards the end of the mainframe age, major advances were made in fields such as networked computing and computer-aided design. Cambridge’s Computer Lab was the home of the world’s first webcam. It was the place where Michael Burrows, the leading computer scientist in search engine development, learned his trade, and where Bjarne Stroustrup, inventor of the hugely popular computer language C++, did his PhD. Without the Lab, early home computers like the BBC Micro, or the low-power chip technology used in iPads and mobile phones, or the Raspberry Pi, might well never have emerged.

We’re a bit overwhelmed to find ourselves discussed in such august company. Eben’s one of the (ha) Distinguished Speakers at today’s celebrations; tomorrow it’s back to normal, but for today we’re enjoying an incredible feeling of taking part in history, and a sense of the extraordinary pace we’ve been moving at for the last 75 years.

Congratulations to everybody at the Lab, past, present and future. Here’s to the next 75 years – let’s make them good ones!

Updated to add: I’ve just been pointed at a slideshow about the Lab’s first 75 years on the BBC News website. It’s short but interesting, and you might recognise the object in the final slide.

Hackspace security system

NESIT is the New England Society of Information and Technology in Connecticut, and they have a made a security system for their hackspace that gives us terrible feelings of envy. Their old RFID door lock, powered by an Arduino, was getting old and came bundled with some problems: it didn’t allow for easy modifications to the database of users (the old setup wrote user information straight to the Arduino’s eeprom), couldn’t output video, and would have been expensive to hook up to the network; running its server all the time would have cost about $200 in electricity over a year.

Running a Pi for a year costs about $3.

So Will, one of the hackspace members, set to work getting a Pi interfacing with an RFID reader, and finding some housing for the whole setup. It had to be secure, lockable and robust: somehow he squirreled up an old outdoor telephone network box made of heavy-duty plastic, which he cleaned up, using a Dremel to modify the door of the box so it could accommodate an LCD screen originally intended for a car reversing system.

Before…

…after. Note glistening result of elbow grease application.

Guts

Will really went to town on this build. He could have stopped there, but has also made sure that the system will tweet when someone enters or leaves. It also monitors temperature, can be controlled from his phone, sends an email alert if someone tries to tamper with the case, and detects motion: if it spots someone walking past, it’ll play a short video about the hackspace.

NESIT’s put details of the build online, and have made this video of the system in action. We note that the “beep” you’re using doubles as an excellent cat-scarer, Will; I have the scratches to prove it.

Bird photography with a Raspberry Pi and a DSLR

Tricky things, birds. Even when you’ve got yourself sorted out with boxes and feeders to entice them into your garden, it can be very difficult to get a decent photograph – they don’t stay still for long, especially if they see you coming (and it is amazing just how adept birds are at spotting the slightest movement – the sort of movement you might make to operate the zoom lens on your camera, for example), and many feeding birds will only visit the table for a few seconds at a time, even if you’re well hidden.

Enter Adrian Bevan and his Raspberry Pi.

Adrian had built a shutter release for his Canon1000D SLR, and decided to extend his new knowledge by making a DIY remote release. He’s been activating it manually, but has also made instructions available for using it with a motion detector (Adrian’s currently using a webcam and a second Pi for this part of the kit), so that the SLR can fire automatically when the Pi it is attached to senses that there was a bird on the table using information streamed from the outdoor Pi.

Your best bet here is to set the camera up in continuous shooting mode so that it’ll take several shots over a few seconds once your target has been spotted. Adrian has put exhaustive instructions on making your own setup on his blog, complete with circuit diagrams and code, alongside some video of the shutter in action.

Speaking of birds, I was, sadly, nowhere near a camera when a sparrowhawk dropped out of the sky to disembowel a blue tit on my front lawn this morning. Rotten shame, that. Oh – and if anybody has any tips on how to stop my bird-feeders being reliably emptied within ten minutes of filling by a horde of marauding starlings, I’m all ears.

Adrian has used that old Pi hackers’ standby, Tupperware, to house the webcam, battery pack and associated Pi in a waterproof environment. Securely housing your DSLR outside in a way that means it won’t get wet but can still take pictures is, obviously, a bit trickier; his is, I think, set up indoors, pointing out of a window, with a whacking great zoom lens attached to the front. If you’ve any ideas on how to set up and leave a good camera outdoors without it getting wet or stolen, please let us know in the comments!

Adafruit WebIDE – new alpha release available

News from across the pond arrived last night, UK time. Our good friends at Adafruit have been working on their web-based integrated development environment (IDE) – hence WebIDE – for the Raspberry Pi, and have made a number of changes based on your requests. This is a big update (“Huge!” says PT), and if you’re already using the WebIDE you’ll notice some changes.

We’re big fans of Adafruit’s WebIDE for the Pi. It offers a nicely structured, easy way to learn how to program, and there’s already lots of support for it (check out Adafruit’s materials or click on the picture above), even though it’s stil in alpha. Beginners should find the visualiser especially helpful; it’s a good way to work out how simple scripts really work, and allows you to see how objects are created, how processes are stacked and so on. We’ve found it’s a real aid to understanding how things fit together, and a great way to explain concepts to people who’ve only just started programming.

Please be aware that because the WebIDE is still a product under development, you may encounter bugs. If you do, please report them using the tool in the editor; user feedback’s really valuable when developing this stuff, and LadyAda, PT, Justin, Tyler and the team want to hear about your experiences.

PT says:

We now have a new offline mode that you can enable with an –offline flag when you install the WebIDE. This mode allows you to bypass using Bitbucket or Github, and should work when not connected to the internet.

We also have a new experimental GitHub mode that allows you to sign in with your GitHub account. This feature is for advanced users that want to use GitHub as their provider. This can be enabled with the –github flag during installation. Please note that GitHub mode does not do some of the automated things (git ssh key setup, etc) that the default installation mode will do.

You can now refresh the left navigator from within the WebIDE, as well as manually update any repositories you have by right-clicking on them, and choosing the option to “Update Repository”.

The full list of new changes for the 0.3.7 version of the WebIDE are as follows:

Github support
• Ability to enable with –github as the default
• Advanced setting
• Requires manual ssh key setup as of yet.
• Most commands are treated as manual mode for now (manual commits, etc).

New Offline mode
• Ability to install with –offline as the default
• need to manually commit, and push changes (similar to the manual git setting)
• Bypasses bitbucket OAuth
• Ability to refresh directories from within the navigator

• New option to clone repositories without updating remote to bitbucket
• New right-click context menu option to update repositories from remote (origin/master for now)
• New Report Bug Link added to footer
• New confirmation dialog for navigating away from unsaved changes…Save Files/Don’t Save/Cancel
• Editor is set to readOnly for any files that shouldn’t change (README, update notes), including empty editor window while navigating.
• Deleting a file or project will now also delete a corresponding scheduled job from the queue.
• Errors cloning repositories are sent to the front-end now.
• Error handling for most git commands now. Notifications visible in WebIDE for failures.
• New Error pages for any issues with the system failing to show pages. Links to ALS WebIDE FAQ for help.
• New Error page specifically for OAuth failures. Adds a button to execute a script to help set the date and time.
• Attempt to set the date on the Pi during installation to prevent OAuth errors.
• Creating files and folders will automatically open them in the editor and navigator.
• Uploaded files will always use the current working directory, instead of uploading to the parent directory now.
• git pull commands are now using the quiet (-q) flag.
• Editor setting for supporting adding a Make link in the editor action bar if a Makefile is detected in the cwd. Not enabled by default.

If you are already running v0.2.0 or higher, you will be able to upgrade (and may already have done) from inside the editor. If you’re running an earlier version, you’ll need to completely remove your old editor and reinstall again. You can find out more at Adafruit. Thanks so much for all your work on this, Adafruit folks – we continue to be bowled over by all the work you’ve been putting into the Pi platform, and we couldn’t be more grateful. We’re looking forward to seeing you when we’re next in NYC!

Use your desktop or laptop screen and keyboard with your Pi

Meltwater has come up with a nice little trick which allows you to use your laptop or desktop’s display and keyboard as the display and keyboard for your Pi. You won’t need to do any soldering or to buy any special equipment: all you need is a network cable.

You’ll be using the network port to do this, so if you were relying on it to get internet connectivity you’ll need a wireless dongle too, but using another device’s keyboard and display means that you can cut right down on the kit you need to carry around if you’re bringing your Pi somewhere to show off your latest project.

Meltwater has made an exhaustive guide to setup for beginners available, alongside a cut-down version for advanced users who don’t need quite so much help.