If you’re at BETT this week, come over to Stand B240 to meet one of the Robs, Clive and a bunch of impaled Jelly Babies.
So here’s a little change of pace after yesterday’s excitement. We’ve noticed a lot of artists working Raspberry Pis into their installations; we’re still very proud that the new Tanks space at Tate Modern had a couple of Pis driving one of their very first exhibits. It makes good sense; the Raspberry Pi’s a lot cheaper and smaller, and a lot less power hungry than the laptops or PC towers that people used to use for this sort of task.
Still in London, we discovered last week that this flotilla of paper boats, which doubles as an array of LEDs and can be controlled by the mobile phones of passers-by, was being exhibited at Canary Wharf. There’s a Raspberry Pi acting as a DHCP and web server as part of the control mechanism, and we find ourselves surprisingly touched at finding a Pi in something so beautiful.
Voyage is an installation from Aether Hemera; you can read more about the setup at their website. I’m not sure how long it’s there for (or even if it’s still in place; we were a little late finding out about this); have any of you London readers had a chance to see it?
There are more pictures of Voyage at Design Boom; they’re well worth a look.
Want to control the temperature of your barbecue, smoker, firepit or clambake over a web interface? Here’s the Raspberry Pi-powered HeaterMeter. Bryan Mayland says:
HeaterMeter for RaspberryPi joins an Arduino / AVR ATmega328 microcontroller with OpenWrt running on a RaspberryPi $35 wonder-computer for the purpose of providing oven-like control of a charcoal BBQ grill via web interface. The microcontroller controls a fan which limits airflow to the pit, displays the current status on a character LCD, and passes the data on to the RaspberyPi which streams real-time updates to connected web browsers. The website also works on mobile browsers running Android or iOS, allowing users to unchain themselves from their grills and partake in many life-enriching activities such as
Going to the grocery store to buy more beer
Going to a bar to drink more beer
Not get off the couch, where your beer is
Possibly other non-beer related hobbies
Dean Ellis has got Monogame running on his Pi. There are details of exactly what hacks he’s used to get it running so well on the YouTube page that this video comes from.
Monogame is an open source implementation of the Microsoft XNA 4 Framework – and it gives us all kinds of ideas about game development on the Pi. You can read some more about Dean and his Pi here.
Make Yourself at Home
We’ve been seeing a lot of visual artists using the Raspberry Pi in their installations. Whether you’re driving video or if you want to drive something with wheels, the Pi offers artists a much cheaper way of getting to their goals than the old “borrow someone’s old laptop” model. We’ve seen Pis being used in the Tate Gallery’s new Tanks in London; we’ve seen them being used in installations at Milton Keynes shopping centre. Most recently, I’ve heard from Martin Beha, who was working on the electronics side of an installation by Austrian artist Robert F Hammerstiel in Hannover. He used Raspberry Pis to make three lawnmower robots talk to each other. (You can see them from about two minutes into this video.) The result is curiously charming.
Click for more on the installation
The communication is established through Wireless LAN. One of the Robots is configured as a server and delivers a (completely wrong but usable) time via NTP for synchronisation. It also calculates the start time for the audio files and delivers it to the other robots via SSH and “at”. The audio is taken directly from the analog output and is amplified by an 18W amplifier module. The sound quality is quite satisfactory for speech.
The devices are powered by a second battery because the manufacturer of the lawn mower robot has built in a function that monitors if additional current is taken from the main battery and stops the robot. The 5V is generated by DC/DC-Converters for car use. Other included circuits are for example a differential amplifier against an audio ground loop and a deep discharge protector.
I chose the Raspberry Pi for reasons of flexibility, size and because there was a very limited budget. The original plan was to communicate via Bluetooth Class 1 dongles and rfcomm to get a virtual serial connection. Because of several bugs in Bluetooth I could not connect the devices and decided to choose Wi-Fi as an alternative. Depending on different (resistor) jumper settings on the GPIO-Port, the RPIs recognize their conversation role after startup and play the right file. The jumper also defines the role as server or client. So I was able to use the same SD-Card image for all robots.
The actual audio files are mp3s of a dialogue about the sense of a robot’s life, spoken by three TV announcers of Austrian national television (Austrians will surely recognize their voices).
STEM – training the teachers
There was a big Raspberry Pi event in Manchester last week, where a large group (including our very own Pete Lomas, accurately described by gocracker.com as “charismatic“) came together for a CPD/networking event for teachers at the Museum of Science and Industry.
Krisma? Bags of it.
We’re not alone in recognising that there’s a lot to be done before a new Computing syllabus arrives at schools next year in helping teachers out of the old ICT mindset and showing them how easy starting with the Pi can be. We’re really pleased to see how seriously teachers are taking the Raspberry Pi, and, as always, incredibly grateful to STEMNET for their tireless volunteering. This was the first of a series of events, where teachers were learning how to use the Pi with Manchester University’s Pi Face, getting to grips with Scratch and Python, and working on cross-curricular activities with the Raspberry Pi. A number of STEM ambassadors from industry also attended, doing that support and mentorship thing that STEMNET does so well. (I don’t think I’ve been to a single Raspberry Pi event that hasn’t been attended by at least one STEM ambassador.) We’d like to thank every one of them, and all of the teachers who are working so hard on getting to grips with a new piece of kit – we’re very grateful.
If you’ve been in the UK this year and you ever pick up the newspaper or turn on the TV news, you’ll be aware that it’s Alan Turing’s centenary. It’s been a wonderful time to launch a project like Raspberry Pi; the Turing centenary, along with the 30th birthday celebrations for the BBC Micro and Spectrum, means that UK computer science, especially in schools, is something that the whole country has actually been paying attention to this year. (And now the Olympics are finished, we hope they’ll look back in this direction again.)
I got talking to Jonathan Hogg, from Output Arts, a small arts collective that has been making multisensory art installations since late 2009. This being the centenary year, they decided to take Turing’s work at Bletchley Park as a starting point for a commission they were given earlier in the year. And they used a Raspberry Pi to do it. Here are the results, and some commentary from Jonathan on the project. I very much hope we’ll be able to go and see I have a message for you… when it’s next on display; hearing what our little computer was doing in this piece made the hairs on the back of my neck prickle, and I really look forward to seeing what Output Arts do with their next Raspberry Pi.
Earlier in the summer, Output Arts won a commission to work with Bletchley Park and Milton Keynes Museum to make an artwork on the theme of “communication” to be shown as part of the Milton Keynes Fringe Festival. Inspired by the work of Alan Turing, we decided to make a piece based on the Delilah speech scrambling system designed by Turing towards the end of the Second World War. The original design of the Delilah system consisted of a pseudo-random number generator and a modulo adder implemented entirely in analogue using valves. Working from the original technical report held at the National Archives in Kew, we wrote a digital simulation of the algorithms in a combination of Python, Cython and NumPy, tuned to run on a Raspberry Pi in realtime.
The equipment of the piece consisted of a box with two knobs, two indicator lights and a hidden motion sensor. This was styled to try and make it look like an old piece of equipment, and was connected to an original WWII military field telephone loaned to us by Milton Keynes Museum. The equipment sat on an old table – also on loan from the museum – and this was placed within a small wooden hut, painted up to look something like a code-breaker hut that might have been found at Bletchley Park during the war. When the box senses motion, it makes the phone ring to encourage participants to lift the receiver. Picking up the receiver activates the system.
We collected messages at Milton Keynes museum and Bletchley Park that were recorded and then scrambled using the Delilah simulation. These scrambled messages were stored as audio files on the SD card of the Pi and then descrambled for listening. The process was deliberately interfered with so that the messages being listened to slowly degrade in quality until they become just noise. The two knobs on the box control the volume of playback and one of the parameters of the descrambling, providing the participant with some sense of control over the listening process – although not enough to put off the eventual destruction of the message. An Arduino board connected to the Raspberry Pi by USB was used to interface with the knobs, lights and motion sensor, and the hook switch and ringer of the telephone; a small circuit connected to the Arduino switches 12V power for the ringer. We also used a USB audio output device as we experienced some distortion of the built-in audio output of the Raspberry Pi under load.
This is the first time we’ve used a RaspberryPi in an artwork, although we have been using Arduino boards for years. It’s been really exciting to be able to try out a Raspberry Pi and has opened up a lot of new possibilities in what we can do in small embedded pieces.
The artwork was shown from 19th to 29th July in the centre of Milton Keynes, and we are hoping to be able to show it again sometime soon, either in London or back in Milton Keynes. Output Arts are very grateful to the staff and volunteers at Bletchley Park and Milton Keynes Museum for their help with the piece.