Tag Archives: Raspberry Pi 3B+

Use PlayStation Buzz! controllers with a Raspberry Pi

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/use-playstation-buzz-controllers-with-a-raspberry-pi/

Buzz! was a favourite amongst my university housemates and me. With popular culture questions asked by an animated Jason Donovan, answered using real-life quiz controllers with a big red button, what’s not to like?

But, as with most of the tech available in the early 2000s, my Buzz! controllers now sit in a box somewhere, dusty and forgotten.

That’s why it is so goshdarn delightful to see PiMyLifeUp breathe new life into these awesome-looking games controllers.

Bringing Buzz! back

The tutorial uses the hidapi library to communicate with the controllers, allowing them to control functions through the Raspberry Pi, and the Raspberry Pi to control the LED within the big red button.

By the end of this tutorial, you will have learned how to read information about all your USB devices, learned how to read data that the devices are sending back and also how to write a library that will act as a simple wrapper to dealing with the device.

Aside from the Buzz! controllers, available on eBay or similar for a few pounds, you only need a Raspberry Pi and its essential peripherals to get started, as the controllers connect directly via USB — thanks, Buzz!

PiMyLifeUp’s tutorial is wonderfully detailed, explaining the hows and whys of the lines of code needed to turn your old Buzz! controllers into a quiz game written in Python that uses the coloured buttons to answer multiple-choice questions.

Guitar Hero, dance mats, Donkey Kong Bongos — what other gaming peripherals would you like to bring back to life?

The post Use PlayStation Buzz! controllers with a Raspberry Pi appeared first on Raspberry Pi.

Raspberry Pi Sense HAT impact recorder for your car

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/raspberry-pi-sense-hat-impact-recorder-for-your-car/

Let the accelerometer and gyroscope of your Raspberry Pi Sense HAT measure and record impact sustained in a car collision.

Raspberry Pi Sense HAT

The Raspberry Pi Sense HAT was originally designed for the European Astro Pi Challenge, inviting schoolchildren to code their own experiments for two Raspberry Pi units currently orbiting the Earth upon the International Space Station.

The Sense HAT is kitted out with an 8×8 RGB LED matrix and a five-button joystick, and it houses an array of useful sensors, including an accelerometer and gyroscope.

And it’s these two sensors that Instructables user Ashu_d has used for their Impact Recorder for Vehicles.

Impact Recorder for Vehicles

“Impact Recorder is designed to record impact sustained to a vehicle while driving or stationary,” Ashu_d explains. Alongside the Raspberry Pi and Sense HAT, the build also uses a Raspberry Pi Camera Module to record footage, saving video and/or picture files to the SD card for you to examine after a collision. “The impacts are stored in the database in the form of readings as well as video/picture.”

By following Ashu_d’s Instructables tutorial, you’re essentially building yourself a black box for your car, recording impact data as the Sense HAT records outside the standard parameters of your daily commute.

“Upon impact, remote users can be verified in real time,” they continue, “and remote users can then watch the saved video or take remote access to the Pi Camera Module and watch events accordingly.”

Ashu_d goes into great detail on how to use Node-RED and MQTT to complete the project, how you can view video in real time using VLC, and how each element works to create the final build over at Instructables.

The post Raspberry Pi Sense HAT impact recorder for your car appeared first on Raspberry Pi.

Playing Snake on a Raspberry Pi word clock

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/playing-snake-on-a-raspberry-pi-word-clock/

I have a soft spot for Raspberry Pi word clocks. True, they may not be as helpful as your standard clock face if you need to tell the time super quickly, but at least they’re easier to read than this binary clock built by engineerish.

“But Alex,” I hear you cry, “word clocks are so done. We’re over them. They’re so 2018. What’s so special about a word clock that you feel it to be worthy of a blog post?”

And the answer, dear reader, is Snake, the best gosh darn game to ever grace the screen of a mobile phone, ever — sorry, Candy Crush.

If you’re looking to build a word clock using your Raspberry Pi, here’s a great tutorial from Benedikt Künzel. And, if you’re looking to upgrade said word clock to another level and introduce it to Snake, well, actually, there isn’t a tutorial for that, yet, but there’s a whole conversation going on about it on Reddit, so you should check that out.

There is, however, a tutorial for coding your own game of Snake Slug on the Raspberry Pi Sense HAT here. So give that a whirl!

Until tomorrow, fair reader, adieu.

The post Playing Snake on a Raspberry Pi word clock appeared first on Raspberry Pi.

Bringing a book to life with Raspberry Pi | Hello World #9

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/bringing-a-book-to-life-with-raspberry-pi-hello-world-9/

Sian Wheatcroft created an interactive story display to enable children to explore her picture book This Bear, That Bear. She explains the project, and her current work in teaching, in the newest issue of Hello World magazine, available now.

The task of promoting my first children’s picture book, This Bear, That Bear, was a daunting one. At the time, I wasn’t a teacher and the thought of standing in front of assembly halls and classrooms sounded terrifying. As well as reading the book to the children, I wanted to make my events interactive using physical computing, showing a creative side to coding and enabling a story to come to life in a different way than what the children would typically see, i.e. animated retellings.

The plan

Coming from a tech-loving family, I naturally gravitated towards the Raspberry Pi, and found out about Bare Conductive and their PiCap. I first envisaged using their conductive paint on the canvas, enabling users to touch the paint to interact with the piece. It would be some sort of scene from the book, bringing some of the characters to life. I soon scrapped that idea, as I discovered that simply using copper tape on the back of the canvas was conductive enough, which also allowed me to add colour to the piece.

I enlisted the help of my two sons (two and five at the time) — they gladly supplied their voices to some of the bears and, my personal favourite on the canvas, the ghost. The final design features characters from the book — when children touch certain areas of the canvas, they hear the voices of the characters.

The back of the canvas, covered in copper tape

Getting the project up and running went pretty smoothly. I do regret making the piece so large, though, as it proved difficult to transport across the country, especially on the busy London Underground!

Interactivity and props

The project added a whole other layer to the events I was taking part in. In schools, I would read the book and have props for the children to wear, allowing them to act out the book as I read aloud. The canvas then added further interaction, and it surprised me how excited the children were about it. They were also really curious and wanted to know how it worked. I enjoyed showing them the back of the canvas with all its copper tape and crocodile clips. They were amazed by the fact it was all run on the Raspberry Pi — such a tiny computer!

The front of the interactive canvas

Fast-forward a few years, and I now find myself in the classroom full-time as a newly qualified teacher. The canvas has recently moved out of the classroom cupboard into my newly developed makerspace, in the hope of a future project being born.

I teach in Year 3, so coding in Python or using the command line on Raspbian may be a little beyond my students. However, I have a keen interest in project-based learning and am hoping to incorporate a host of cross-curricular activities with my students involving the canvas.

I hope to instil a love for digital making in my students and, in turn, show senior leaders what can be done with such equipment and projects.

A literacy project

This work really lends itself to a literacy project that other educators could try. Perhaps you’re reading a picture book or a more text-based piece: why not get the students to design the canvas using characters from the story? The project would also work equally well with foundation subjects like History or Science. Children could gather information onto the canvas, explaining how something works or how something happened. The age of the children would influence the level of involvement they had in the rest of the project’s creation. The back end could be pre-made — older children could help with the copper tape and wiring, while younger children could stop at the design process.

Part of the project is getting the children to create sounds to go with their design, enabling deeper thinking about a story or topic.

It’s about a collaborative process with the teacher and students, followed by the sharing of their creation with the broader school community.

Get Hello World magazine issue 9 for free

The brand-new issue of Hello World is available right now as a free PDF download from the Hello World website.

UK-based educators can also subscribe to receive Hello World as printed magazine FOR FREE, direct to their door. And those outside the UK, educator or not, can subscribe to receive free digital issues of Hello World in their inbox on the day of their release.

Head to helloworld.raspberrypi.org to sign up today!

The post Bringing a book to life with Raspberry Pi | Hello World #9 appeared first on Raspberry Pi.

Saving biologists’ time with Raspberry Pi

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/saving-biologists-time-with-raspberry-pi/

In an effort to save themselves and fellow biologists hours of time each week, Team IoHeat are currently prototyping a device that allows solutions to be heated while they are still in cold storage.

The IoHeat team didn’t provide any photos with their project writeup, so here’s a picture of a bored biologist that I found online

Saving time in the lab

As they explain in their prototype write-up:

As scientists working with living organisms (from single cells to tissue samples), we are often required to return to work outside of normal hours to maintain our specimens. In many cases, the compounds and solutions we are using in our line of work are stored at 4°C and need to reach 37°C before they can be used. So far, in order to do this we need to return to our workplace early, incubate our solutions at 37°C for 1–2h, depending on the required volume, and then use them in processes that often take a few minutes. It is clear that there is a lot of room here to improve our efficiency.

Controlling temperatures with Raspberry Pi

These hours wasted on waiting for solutions to heat up could be better spent elsewhere, so the team is building a Raspberry Pi–powered device that will allow them to control the heating process remotely.

We are aiming to built a small incubator that we can store in a cold room/fridge, and that can be activated remotely to warm up to a defined temperature. This incubator will enable us to safely store our reagents at low temperature and warm them up remotely before we need to use them, saving an estimate of 12h per week per user.

This is a great project idea, and they’ve already prototyped it using a Raspberry Pi, heating element, and fan. Temperature and humidity sensors connected to the Raspberry Pi monitor conditions inside the incubator, and the prototype can be controlled via Telegram.

Find out more about the project on Hackster.

We’ve got more than one biologist on the Raspberry Pi staff, so we have a personal appreciation for the effort behind this project, and we look forward to seeing how IoHeat progresses in the future.

The post Saving biologists’ time with Raspberry Pi appeared first on Raspberry Pi.

Take the Wizarding World of Harry Potter home with you

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/take-the-wizarding-world-of-harry-potter-home-with-you/

If you’ve visited the Wizarding World of Harry Potter and found yourself in possession of an interactive magic wand as a souvenir, then you’ll no doubt be wondering by now, “What do I do with it at home though?”

While the wand was great for setting off window displays at the park itself, it now sits dusty and forgotten upon a shelf. But it still has life left in it — let Jasmeet Singh show you how.

Real Working Harry Potter Wand With Computer Vision and ML

A few months back my brother visited Japan and had real wizarding experience in the Wizarding World of Harry Potter at the Universal Studios made possible through the technology of Computer Vision. At the Wizarding World of Harry Potter in Universal Studios the tourists can perform “real magic” at certain locations(where the motion capture system is installed) using specially made wands with retro-reflective beads at the tip.

How do Harry Potter interactive wands work?

The interactive displays at Universal Studios’ Wizarding World of Harry Potter have infrared cameras in place, which are ready to read the correct movements of retroflector-tipped wands. Move your wand in the right way, and the cameras will recognise your spell and set window displays in motion. Oooooo…magic!

How do I know this? Thanks to William Osman and Allen Pan, who used this Wizarding World technology to turn cheap hot dogs into their own unique wands! Those boys…

Hacking Wands at Harry Potter World

How to make your very own mostly-functional interactive wand. Please don’t ban me from Universal Studios. Links on my blog: http://www.williamosman.com/2017/12/hacking-harry-potter-wands.html Allen’s Channel: https://www.youtube.com/channel/UCVS89U86PwqzNkK2qYNbk5A Support us on Patreon: https://www.patreon.com/williamosman Website: http://www.williamosman.com/ Facebook: https://www.facebook.com/williamosmanscience/ InstaHam: https://www.instagram.com/crabsandscience/ CameraManJohn: http://www.johnwillner.com/

For his Raspberry Pi-enabled wand project, Jasmeet took that same Wizarding World concept to create a desktop storage box that opens and closes in response to the correct flicks of a wand.

A simple night vision camera can be used as our camera for motion capture as they also blast out infrared light which is not visible to humans but can be clearly seen with a camera that has no infrared filter.

So, the video stream from the camera is fed into a Raspberry Pi which has a Python program running OpenCV which is used for detecting, isolating and tracking the wand tip. Then we use SVM (Simple Vector Machine) algorithm of machine learning to recognize the pattern drawn and accordingly control the GPIOs of the raspberry pi to perform some activities.

For more information on the project, including all the code needed to get started, head over to hackster.io to find Jasmeet’s full tutorial.

The post Take the Wizarding World of Harry Potter home with you appeared first on Raspberry Pi.

Steampunk-inspired Raspberry Pi enclosure | HackSpace magazine #20

Post Syndicated from Andrew Gregory original https://www.raspberrypi.org/blog/steampunk-inspired-raspberry-pi-enclosure-hackspace-magazine-20/

Who doesn’t like a good-looking case for their Raspberry Pi?

Exactly.

We’ve seen many homemade cases over the years, from 3D-printed enclosures to LEGO, Altoid tins and gravity-defying Zelda-themed wonderments. We love them all as much as we love own — our own case being this one if you fancy one — and always look forward to seeing more.

Cue this rather fancy steampunk-inspired enclosure made by Erich Styger, as featured in the latest issue of HackSpace magazine.

The magazine states:

This steampunk enclosure for the Raspberry Pi by Erich Styger was laser-cut out of 4 mm birch plywood, and stained to make it look a bit more 1890s. It’s built to fit a Raspberry Pi with an NXP tinyK22 board and a battery backup, and there are ports artfully crafted into it so that the system is fully functional even when the box is closed.

Those gears aren’t just for show: turn the central wheel on the front of the box to open the enclosure and get access to the electronics inside.



Cool, right?

What cases have you made for your Raspberry Pi? Let us know in the comments, or by tagging @Raspberry_Pi and @HackSpaceMag on Twitter.

HackSpace magazine is out now

You can read the rest of this feature in HackSpace magazine issue 20, out today in Tesco, WHSmith, and all good independent UK newsagents.

Or you can buy HackSpace mag directly from us — worldwide delivery is available. And if you’d like to own a handy digital version of the magazine, you can also download a free PDF.

The post Steampunk-inspired Raspberry Pi enclosure | HackSpace magazine #20 appeared first on Raspberry Pi.

Chat to Ada Lovelace via a Raspberry Pi

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/chat-ada-lovelace-raspberry-pi/

Our friends, 8 Bits and a Byte, have built a Historic Voicebot, allowing users to chat to their favourite historical figures.

It’s rather marvellous.

The Historic Voicebot

Have a chat with your favourite person from the past with the Historic Voicebot! With this interactive installation, you can talk to a historical figure through both chat and voice. Made using Dialogflow, Node.js, HTML Canvas, an AIY Voice Kit, a Raspberry Pi and a vintage phone.

All the skills

Coding? Check. Woodwork? Check. Tearing apart a Google AIY Kit in order to retrofit it into a vintage telephone while ensuring it can still pick up voice via the handset? Check, check, check – this project has it all.

The concept consists of two parts:

  • A touchscreen with animations of a historical figure. The touchscreen also displays the dialog and has buttons so people can ask an FAQ.
  • A physical phone that captures speech and gives audio output, so it can be used to ask questions and listen to the answer.

While Nicole doesn’t go into full detail in the video, the Ada animation uses Dialogflow, Node.js, and HTML Canvas to work, and pairs up with the existing tech in the Google AIY Kit.

And, if you don’t have an AIY Kit to hand, don’t worry; you can have the same functionality using a standard USB speaker and microphone, and Google Home running on a Raspberry Pi.

You can find a tutorial for the whole project on hackster.io.

Follow 8 Bits and a Byte

There are a lot of YouTube channels out there that don’t have the follow count we reckon they deserve, and 8 Bits and a Byte is one of them. So, head to their channel and click that subscribe button, and be sure to check out their other videos for some more Raspberry Pi goodness.

The post Chat to Ada Lovelace via a Raspberry Pi appeared first on Raspberry Pi.

An in-flight entertainment system that isn’t terrible

Post Syndicated from Helen Lynn original https://www.raspberrypi.org/blog/an-in-flight-entertainment-system-that-isnt-terrible/

No Alex today; she’s tragically germ-ridden and sighing weakly beneath a heap of duvets on her sofa. But, in spite of it all, she’s managed to communicate that I should share Kyle‘s Raspberry Pi in-flight entertainment system with you.

I made my own IN-FLIGHT entertainment system! ft. Raspberry Pi

Corsair Ironclaw RGB Gaming Mouse: http://bit.ly/2vFwYw5 From poor A/V quality to lackluster content selection, in-flight entertainment centers are full of compromises. Let’s create our own using a Raspberry Pi 3 B+!

Kyle is far from impressed with the in-flight entertainment on most planes: the audio is terrible, the touchscreens are annoyingly temperamental, and the movie selection is often frustratingly limited. So, the night before a morning flight to visit family (congrats on becoming an uncle, Kyle! We trust you’ll use your powers only for good!), he hit upon the idea of building his own in-flight entertainment system, using stuff he already had lying around.

Yes, we know, he could just have taken a tablet with him. But we agree with him that his solution is way funner. It’s way more customisable too. Kyle’s current rushed prototype features a Raspberry Pi 3B+ neatly cable-tied into a drilled Altoids tin lid, which is fixed flush to the back of a 13.3-inch portable monitor with adhesive Velcro. He’s using VLC Media Player, which comes with Raspbian and supports a lot of media control functions straight out of the box; this made using his mouse and mini keyboard a fairly seamless experience. And a handy magnetic/suction bracket lets him put the screen in the back of the seat in front to the best possible use: as a mounting surface.

As Kyle says, “Is it ridiculous? I mean, yes, obviously it’s ridiculous, but would you ever consider doing something like this?”

The post An in-flight entertainment system that isn’t terrible appeared first on Raspberry Pi.

Playback your favourite records with Plynth

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/playback-your-favourite-records-with-plynth/

Use album artwork to trigger playback of your favourite music with Plynth, the Raspberry Pi–powered, camera-enhanced record stand.

Plynth Demo

This is “Plynth Demo” by Plynth on Vimeo, the home for high quality videos and the people who love them.

Record playback with Plynth

Plynth uses a Raspberry Pi and Pi Camera Module to identify cover artwork and play the respective album on your sound system, via your preferred streaming service or digital library.

As the project’s website explains, using Plynth is pretty simple. Just:

  • Place a n LP, CD, tape, VHS, DVD, piece of artwork – anything, really – onto Plynth
  • Plynth uses its built-in camera to scan and identify the work
  • Plynth starts streaming your music on your connected speakers or home stereo system

As for Plynth’s innards? The stand houses a Raspberry Pi 3B+ and Camera Module, and relies on “a combination of the Google Vision API and OpenCV, which is great because there’s a lot of documentation online for both of them”, states the project creator, sp_cecamp, on Reddit.

Other uses

Some of you may wonder why you wouldn’t have your records with your record player and, as such, use that record player to play those records. If you are one of these people, then consider, for example, the beautiful Damien Rice LP I own that tragically broke during a recent house move. While I can no longer play the LP, its artwork is still worthy of a place on my record shelf, and with Plynth I can still play the album as well.

In addition, instead of album artwork to play an album, you could use photographs, doodles, or type to play curated playlists, or, as mentioned on the website, DVDs to play the movies soundtrack, or CDs to correctly select the right disc in a disc changer.

Convinced or not, I think what we can all agree on is that Plynth is a good-looking bit of kit, and at Pi Towers look forward to seeing where they project leads.

The post Playback your favourite records with Plynth appeared first on Raspberry Pi.

Ghost hunting in schools with Raspberry Pi | Hello World #9

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/digital-ghost-hunt-raspberry-pi-hello-world-9/

In Hello World issue 9, out today, Elliott Hall and Tom Bowtell discuss The Digital Ghost Hunt: an immersive theatre and augmented reality experience that takes a narrative-driven approach in order to make digital education accessible.The Digital Ghost Hunt - Raspberry Pi Hello World

The Digital Ghost Hunt combines coding education, augmented reality, and live performance to create an immersive storytelling experience. It begins when a normal school assembly is disrupted by the unscheduled arrival of Deputy Undersecretary Quill of the Ministry of Real Paranormal Hygiene, there to recruit students into the Department’s Ghost Removal Section. She explains that the Ministry needs the students’ help because children have the unique ability to see and interact with ghostly spirits.

The Digital Ghost Hunt - Raspberry Pi Hello World

Under the tutelage of Deputy Undersecretary Quill and Professor Bray (the Ministry’s chief scientist), the young ghost-hunters learn how to program and use their own paranormal detectors. These allow students to discover ghostly traces, translate Morse code using flickering lights, and find messages left in ultraviolet ectoplasm. Meanwhile, the ghost communicates through a mixture of traditional theatrical effects and the poltergeist potential of smart home technology. Together, students uncover the ghost’s identity, discover her reason for haunting the building, unmask a dastardly villain, find a stolen necklace, clear the ghost’s name, right an old wrong, and finally set the ghost free.

The Digital Ghost Hunt - Raspberry Pi Hello World

The project conducted two successful test performances at the Battersea Arts Centre in South London in November 2018, funded by a grant from AHRC’s New Immersive Experiences Programme, led by Mary Krell of Sussex University. Its next outing will be at York Theatre Royal in August.

Adventures in learning

The Digital Ghost Hunt arose out of a shared interest in putting experimentation and play at the centre for learners. We felt that the creative, tinkering spirit of earlier computing — learning how to program BASIC on an Atari 800XL to create a game, for example — was being supplanted by a didactic and prescriptive approach to digital learning. KIT Theatre’s practice — creating classroom adventures that cast pupils as heroes in missions — is also driven by a less trammelled, more experiment-led approach to learning.

We believe that the current Computer Science curriculum isn’t engaging enough for students. We wanted to shift the context of how computer science is perceived, from ‘something techy and boyish’ back to the tool of the imagination that it should be. We did this by de-emphasising the technology itself and, instead, placing it in the larger context of a ghost story. The technology becomes a tool to navigate the narrative world — a means to an end rather than an end in itself. This helps create a more welcoming space for students who are bored or intimidated by the computer lab: a space of performance, experiment, and play.

Ghosts and machines

The device we built for the students was the SEEK Ghost Detector, made from a Raspberry Pi and a micro:bit, which Elliot stapled together. The micro:bit was the device’s interface, which students programmed using the block-based language MakeCode. The Raspberry Pi handled the heavier technical requirements of the show, and communicated them to the micro:bit in a form students could use. The detector had no screen, only the micro:bit’s LEDs. This meant that students’ attention was focused on the environment and what the detector could tell them about it, rather than having their attention pulled to a screen to the exclusion of the ‘real’ world around them.

In addition to the detector, we used a Raspberry Pi to make ordinary smart home technology into our poltergeist. It communicated with the students using effects such as smart bulbs that flashed in Morse code, which the students could then decode on their devices.

To program their detectors, students took part in a series of four lessons at school, focused on thinking like a programmer and the logic of computing. Two of the lessons featured significant time spent programming the micro:bit. The first focused on reading code on paper, and students were asked to look out for any bugs. The second had students thinking about what the detector will do, and acting out the steps together, effectively ‘performing’ the algorithm.

We based the process on KIT Theatre’s Adventures in Learning model, and its Theory of Change:

  • Disruption: an unexpected event grabs attention, creating a new learning space
  • Mission: a character directly asks pupils for their help in completing a mission
  • Achievement: pupils receive training and are given agency to successfully complete the mission

The Ghost Hunt

During these lessons, Deputy Undersecretary Quill kept in touch with the students via email, and the chief scientist sent them instructional videos. Their work culminated in their first official assignment: a ghost haunting the Battersea Arts Centre — a 120-year-old former town hall. After arriving, students were split into four teams, working together. Two teams analysed evidence at headquarters, while the others went out into places in the building where we’d hidden ghostly traces that their detectors would discover. The students pooled their findings to learn the ghost’s story, and then the teams swapped roles. The detectors were therefore only one method of exploring the narrative world. But the fact that they’d learned some of the code gave students a confidence in using the detectors — a sense of ownership. During one performance, one of the students pointed to a detector and said: “I made that.”

Future of the project

The project is now adapting the experience into a family show, in partnership with Pilot Theatre, premiering in York in summer 2019. We aim for it to become the core of an ecosystem of lessons, ideas, and activities — to engage audiences in the imaginative possibilities of digital technology.

You can find out more about the Digital Ghost Hunt on their website, which also includes rather lovely videos that Vimeo won’t let me embed here.

Hello World issue 9

The brand-new issue of Hello World is out today, and available right now as a free PDF download from the Hello World website.

Hello World issu 9

UK-based educators can also sign up to receive Hello World as printed magazine FOR FREE, direct to their door, by signing up here. And those outside the UK, educator or not, can subscribe to receive new issues of Hello World in their inbox on the day of release.

The post Ghost hunting in schools with Raspberry Pi | Hello World #9 appeared first on Raspberry Pi.

Quick Fix — a vending machine for likes and followers

Post Syndicated from Liz Upton original https://www.raspberrypi.org/blog/quick-fix-a-vending-machine-for-likes-and-followers/

Sometimes we come across a project that just scores a perfect 10 on all fronts. This is one of them: an art installation using Raspberry Pi that has something interesting to say, does it elegantly, and is implemented beautifully (nothing presses our buttons like a make that’s got a professionally glossy finish like this).

Quick Fix is a vending machine (and art installation) that sells social media likes and followers. Drop in a coin, enter your social media account name, and an army of fake accounts will like or follow you. I’ll leave the social commentary to you. Here’s a video from the maker, Dries Depoorter:

Quick Fix – the vending machine selling likes and followers

Quick Fix in an interactive installation by Dries Depoorter. The artwork makes it possible to buy followers or likes in just a few seconds. For a few euros you already have 200 of likes on Instagram. “Quick Fix “is easy to use. Choose your product, pay and fill in your social media username.

There’s a Raspberry Pi 3B+ in there, along with an Arduino, powering a coin acceptor and some I2C LCD screens. Then there’s a stainless steel heavy-duty keyboard, which we’re lusting after (a spot of Googling unearthed this, which appears to be the same thing, if you’re in the market for a panel-mounted beast of a keyboard).

This piece was commissioned by Pixelache, a cultural association from Helsinki, whose work looks absolutely fascinating if you’ve got a few minutes to browse. Thanks to them and to Dries Depoorter — I have a feeling this won’t be the last of his projects we’re going to feature here.

The post Quick Fix — a vending machine for likes and followers appeared first on Raspberry Pi.

The NSFW Roomba that screams when it bumps into stuff

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/the-nsfw-roomba-that-screams-when-it-bumps-into-stuff/

Hide yo’ kids, hide yo’ wife — today’s project is NSF(some)W, or for your kids. LOTS OF SWEARS. You have been warned. We’re not embedding the video here so you can decide for yourself whether or not to watch it — click on the image below to watch a sweary robot on YouTube.

Sweary Roomba

Michael Reeves is best known for such… educational Raspberry Pi projects as:

He’s back, this time with yet another NSFW (depending on your W) project that triggers the sensors in a Roomba smart vacuum to scream in pain whenever it bumps into an object.

Because why not?

How it’s made

We have no clue. So very done with fans asking for the project to be made — “I hate every single one of you!” — Michael refuses to say how he did it. But we know this much is true: the build uses optical sensors, relays, a radio receiver, and a Raspberry Pi. How do I know this? Because he showed us:

Roomba innards

But as for the rest? We leave it up to you, our plucky community of tinkerers, to figure it out. Share your guesses in the comments.

More Michael Reeves

Michael is one of our Pi Towers guilty pleasures and if, like us, you want to watch more of his antics, you should subscribe to him on YouTube.

The post The NSFW Roomba that screams when it bumps into stuff appeared first on Raspberry Pi.

Play musical chairs with Marvel’s Avengers

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/play-musical-chairs-marvels-avengers/

You read that title correctly.

I played musical chairs against the Avengers in AR

Planning on teaching a 12 week class on mixed reality development starting in June. Apply if interested – http://bit.ly/3016EdH

Playing with the Avengers

Abhishek Singh recently shared his latest Unity creation on Reddit. And when Simon, Righteous Keeper of the Swag at Pi Towers, shared it with us on Slack because it uses a Raspberry Pi, we all went a little doolally.

As Abhishek explains in the video, the game uses a Raspberry Pi to control sensors and lights, bridging the gap between augmented reality and the physical world.

“The physical world communicates with the virtual world through these buttons. So, when I sit down on a physical chair, and press down on it, the virtual characters know that this chair is occupied,” he explains, highlighting that the chairs’ sensors are attached to a Raspberry Pi. To save the physical-world player from accidentally sitting on Thanos’s lap, LEDs, also attached to the Pi, turn on when a chair is occupied in the virtual world.

Turning the losing Avenger to dust? Priceless 👌

Why do you recognise Abhishek Singh?

You might be thinking, “Where do I recognise Abhishek Singh from?” I was asking myself this for a solid hour — until I remembered Peeqo, his robot that only communicates through GIF reactions. And Instagif NextStep, his instant camera that prints GIFs!

First GIFs, and now musical chairs with the Avengers? Abhishek, it’s as if you’ve understood the very soul of the folks who work at Pi Towers, and for that, well…

The post Play musical chairs with Marvel’s Avengers appeared first on Raspberry Pi.

Video call with a Raspberry Pi and Google Duo

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/video-call-with-a-raspberry-pi-and-google-duo/

Use Google Duo and a Raspberry Pi to build a video doorbell for your home so you can always be there to answer your door, even when you’re not actually there to answer your door.

“Martin Mander builds a good build,” I reply to Liz Upton as she shares this project, Martin’s latest one, with me on Slack. We’re pretty familiar with his work here at Raspberry Pi! Previously, we’ve shared his Google AIY retrofit intercom, upcycled 1970s TV with built-in Raspberry Pi TV HAT, and Batinator. We love the extra step that Martin always takes to ensure the final result of each project is clean-cut and gorgeous-looking, with not even a hint of hot glue in sight.

Raspberry Pi video doorbell

“I’ve always fancied making a video doorbell using a Raspberry Pi,” explains Martin in the introduction to his project on Hackster.io. “[B]ut until recently I couldn’t find an easy way to make video calls that would both work in a project and be straightforward for others to recreate.”

By ‘recently’, he means February of this year, when Google released their Duo video chat application for web browsers.

With a Raspberry Pi 3B+ and a webcam in hand, Martin tested the new release, and lo and behold, he was able to video-call his wife with relative ease via Chromium, Raspbian‘s default browser.

“The webcam I tested had a built-in microphone, and even on the first thrown-together test call, the quality was great. This was a very exciting moment, unlocking the potential of the video doorbell project as well as many other possibilities.”

By accident, Martin also discovered that you can run Google Duo out of the browser, even on the Raspberry Pi. This allowed him to strip away all the unnecessary “Chromium furniture”.

But, if this was to be a video doorbell, how was he to tell the Raspberry Pi to call his mobile phone when the doorbell was activated?

“If Duo were a full app, then command line options might be available, for example to launch the app and immediately call a specific contact. In the absence of this (for now?) I needed to find a way to automatically start a call with a GPIO button press.”

To accomplish this, Martin decided to use PyUserInput, a community-built cross-platform module for Python. “The idea was to set up a script to wait for a button press, then move the mouse to the Contacts textbox, type the name of the contact, press Enter and click Video Call“, Martin explains. And after some trial and error — and calls to the wrong person — his project was a working success.

To complete the build, Martin fitted the doorbell components into a 1980s intercom (see his previous intercom build), wired them through to a base unit inside the home, and then housed it all within an old Sony cassette player.

The final result? A functional video doorbell that is both gorgeous and practical. You can find out more about the project on the Hackster.io project page.

The post Video call with a Raspberry Pi and Google Duo appeared first on Raspberry Pi.

Make a retro console with RetroPie and a Raspberry Pi — part 2

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/retro-console-with-retropie-raspberry-pi-2/

Here’s part two of Lucy Hattersley’s wonderful retro games console tutorial. Part 1 of the tutorial lives here, for those of you who missed it.

Choose the network locale

RetroPie boots into EmulationStation, which is your starter interface. It’s currently displaying just the one option, RetroPie, which is used to set up the emulation options. As you add games to RetroPie, other systems will appear in EmulationStation.

With RetroPie selected, press the A button on the gamepad to open the configuration window. Use the D-pad to move down the options and select WiFi. You will see a warning message: ‘You don’t currently have your WiFi country set…’. Press the D-pad left to choose Yes, and press A. The interface will open raspi-config. At this point, it’s handy to switch to the keyboard and use that instead.

Choose 4 Localisation Options, and press the right arrow key on the keyboard to highlight Select, then press Enter.

Now choose 4 Change Wi-fi Country and pick your country from the list. We used GB Britain (UK). Highlight OK and press Enter to select it.

Now move right twice to choose Finish and press Enter. This will reboot the system.

Connect to wireless LAN

If you have a Raspberry Pi with an Ethernet connection, you can use an Ethernet cable to connect directly to your router/modem or network.

More likely, you’ll connect the Raspberry Pi to a wireless LAN network so you can access it when it’s beneath your television.

Head back into RetroPie from EmulationStation and down to the WiFi setting; choose Connect to WiFi network.

The window will display a list of nearby wireless LAN networks. Choose your network and use the keyboard to enter the wireless LAN password. Press Enter when you’re done. Choose the Exit option to return to the RetroPie interface.

Configuration tools

Now choose RetroPie Setup and then Configuration Tools. Here, in the Choose an option window, you’ll find a range of useful tools. As we’re using a USB gamepad, we don’t need the Bluetooth settings, but it’s worth noting they’re here.

We want to turn on Samba so we can share files from our computer directly to RetroPie. Choose Samba and Install RetroPie Samba shares, then select OK.

Now choose Cancel to back up to the Choose an option window, and then Back to return to the RetroPie-Setup script.

Run the setup script

Choose Update RetroPie-Setup script and press Enter. After the script has updated, press Enter again and you’ll be back at the Notice: window. Press Enter and choose Basic install; press Enter, choose Yes, and press Enter again to begin the setup and run the configuration script.

When the script has finished, choose Perform a reboot and Yes.

Turn on Samba in Windows

We’re going to use Samba to copy a ROM file (a video game image) from our computer to RetroPie.

Samba used to be installed by default in Windows, but it has recently become an optional installation. In Windows 10, click on the Search bar and type ‘Control Panel’. Click on Control Panel in the search results.

Now click Programs and Turn Windows features on or off. Scroll down to find SMB 1.0/CIFS File Sharing Support and click the + expand icon to reveal its options. Place a check in the box marked SMB 1.0/CIFS Client. Click OK. This will enable Samba client support on your Windows 10 PC so it can access the Raspberry Pi.

We’ve got more information on how Samba works on The MagPi’s website.

Get the game

On your Windows PC or Mac, open a web browser, and visit the Blade Buster website. This is a homebrew video game designed by High Level Challenge for old NES systems. The developer’s website is in Japanese — just click BLADE BUSTER Download to save the ROM file to your Downloads folder.

Open a File Explorer (or Finder) window and locate the BB_20120301.zip file in your Downloads folder. Don’t unzip the file.

Click on Network and you’ll see a RETROPIE share. Open it and locate the roms folder. Double-click roms and you’ll see folders for many classic systems. Drag and drop the BB_20120301.zip file and place it inside the nes folder.

Play the game

Press the Start button on your gamepad to bring up the Main Menu. Choose Quit and Restart EmulationStation. You’ll now see a Nintendo Entertainment System option with 1 Games Available below it. Click it and you’ll see BB_20120301 — this is Blade Buster. Press A to start the game. Have fun shooting aliens. Press Start and Analog (or whatever you’ve set as your hotkey) together when you’re finished; this will take you back to the game selection in EmulationStation.

If you’ve been setting up RetroPie on your monitor, now is the time to move it across to your main television. The RetroPie console will boot automatically and connect to the network, and then you can move ROM files over to it from your PC or Mac. At this point, you may notice black borders around the screen; if so, see the Fix the borders tip.

Enjoy your gaming system!

More top tips from Lucy

Change the resolution

Some games were designed for a much lower resolution, and scaling them up can look blocky on modern televisions. If you’d prefer to alter the resolution, choose ‘RetroPie setup’. Open raspi-config, Advanced Options, and Resolution. Here you’ll find a range of other resolution options to choose from.

Fix the borders

These are caused by overscan. Choose RetroPie from EmulationStation and raspi-config. Now select Advanced Options > Overscan and select No on the ‘Would you like to enable compensation for displays with overscan?’ window. Choose OK and then Finish. Choose Yes on the Reboot Now window. When the system has rebooted, you will see the borders are gone.

The MagPi magazine issue 81

This article is from the latest issue of The MagPi magazine, which is out today and can be purchased online, at the Raspberry Pi Store, or from many newsagents and bookshops, such as WHSmith and Barnes & Noble.

The MagPi magazine issue 81

You can also download issue 81 for free from The MagPi website, where you’ll also find information on subscription options, and the complete MagPi catalogue, including Essentials guides and books, all available to download for free.

the MagPi subscription

The post Make a retro console with RetroPie and a Raspberry Pi — part 2 appeared first on Raspberry Pi.

Make a retro console with RetroPie and a Raspberry Pi — part 1

Post Syndicated from Lucy Hattersley original https://www.raspberrypi.org/blog/retro-console-with-retropie-raspberry-pi-1/

Discover classic gaming on the Raspberry Pi and play homebrew ROMs, with this two-part tutorial from The MagPi Editor Lucy Hattersley.

Raspberry Pi retro games console

Turning a Raspberry Pi device into a retro games console is a fun project, and it’s one of the first things many a new Pi owner turns their hand to.

The appeal is obvious. Retro games are fun, and from a programming perspective, they’re a lot easier to understand than modern 3D powerhouses. The Raspberry Pi board’s small form factor, low power usage, HDMI connection, and wireless networking make it a perfect micro-console that can sit under your television.

RetroPie

There are a bunch of different emulators around for Raspberry Pi. In this tutorial, we’re going to look at RetroPie.

RetroPie combines Raspbian, EmulationStation, and RetroArch into one handy image. With RetroPie you can emulate arcade games, as well as titles originally released on a host of 8-bit, 16-bit, and even 32- and 64-bit systems. You can hook up a joypad; we’re going to use the Wireless USB Game Controller, but most other USB game controllers will work.

You can also use Bluetooth to connect a controller from most video games consoles. RetroPie has an interface that will be very familiar to anyone who has used a modern games console, and because it is open-source, it is constantly being improved.

You can look online for classic games, but we prefer homebrew and modern releases coded for classic systems. In this tutorial, we will walk you through the process of setting up RetroPie, configuring a gamepad, and running a homebrew game called Blade Buster.

Get your microSD card ready

RetroPie is built on top of Raspbian (the operating system for Raspberry Pi). While it is possible to install RetroPie from the desktop interface, it’s far easier to format a microSD card† and copy a new RetroPie image to the blank card. This ensures all the settings are correct and makes setup much easier. Our favourite method of wiping microSD cards on a PC or Apple Mac is to use SD Memory Card Formatter.

Attach the microSD card to your Windows or Mac computer and open SD Card Formatter. Ensure the card is highlighted in the Select card section, then click Format.

Download RetroPie

Download the RetroPie image. It’ll be downloaded as a gzip file; the best way to expand this on Windows is using 7-Zip (7-zip.org).

With 7-Zip installed, right-click the retropie-4.4-rpi2_rpi3.img.gz file and choose 7-Zip > Extract here. Extract GZ files on a Mac or Linux PC using gunzip -k <filename.gz> (the -k option keeps the original GZ file).

gunzip -k retropie-4.4-rpi2_rpi3.img.gz

Flash the image

We’re going to use Etcher to copy the retropie-4.4-rpi2_rpi3.img file to our freshly formatted microSD card. Download Etcher. Open Etcher and click Select Image, then choose the retropie-4.4-rpi2_rpi3.img image file and click Open.

Etcher should have already located the microSD card; remove and replace it if you see a Select Drive button. Click Flash! to copy the RetroPie image to the microSD card.

See our guide for more information on how to use Etcher to flash SD cards.

Set up the Raspberry Pi

Insert the flashed microSD card to your Raspberry Pi. Now attach the Raspberry Pi to a TV or monitor using the HDMI cable. Connect the USB dongle from the Wireless USB Game Controller to the Raspberry Pi. Also attach a keyboard (you’ll need this for the setup process).

Insert the batteries in the Wireless USB Game Controller and set the power switch (on the back of the device) to On. Once everything is connected, attach a power supply to the Raspberry Pi.

See our quickstart guide for more detailed information on setting up a Raspberry Pi.

Configure the gamepad

When RetroPie starts, you should see Welcome screen displaying the message ‘1 gamepad detected’. Press and hold one of the buttons on the pad, and you will see the Configuring screen with a list of gamepad buttons and directions.

Tap the D-pad (the four-way directional control pad on the far left) up on the controller and ‘HAT 0 UP’ will appear. Now tap the D-pad down.
Map the A, B, X, Y buttons to:

A: red circle
B: blue cross
X: green triangle
Y: purple square

The Left and Right Shoulder buttons refer to the topmost buttons on the rear of the controller, while the Triggers are the larger lower buttons.

Push the left and right analogue sticks in for the Left and Right Thumbs. Click OK when you’re done.

Top tips from Lucy

Install Raspbian desktop

RetroPie is built on top of the Raspbian operating system. You might be tempted to install RetroPie on top of the Raspbian with Desktop interface, but it’s actually much easier to do it the other way around. Open RetroPie from EmulationStation and choose RetroPie setup. Select Configuration tools and Raspbian tools. Then choose Install Pixel desktop environment and Yes.

When it’s finished, choose Quit and Restart EmulationStation. When restarted, EmulationStation will display a Ports option. Select it and choose Desktop to boot into the Raspbian desktop interface.

Username and password

If RetroPie asks you for the username and password during boot, the defaults are pi and raspberry.

The MagPi magazine issue 81

The rest of this article can be found in the latest issue of The MagPi magazine, which is out now and can be purchased online, at the Raspberry Pi Store, or from many independent bookshops, such as WHSmith and Barnes & Noble. We’ll also post the second half on the blog tomorrow!

The MagPi magazine issue 81

You can also download issue 81 for free from The MagPi website, where you’ll find information on subscription options, and the complete MagPi catalogue, including Essentials guides and books, all available to download for free.

the MagPi subscription

The post Make a retro console with RetroPie and a Raspberry Pi — part 1 appeared first on Raspberry Pi.

Build a SatNOGS ground station with a Raspberry Pi 3B+ | HackSpace magazine #18

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/build-a-satnogs-ground-station-raspberry-pi-3b-hackspace-magazine-18/

The big feature on outer space in issue 18 of HackSpace magazine, available from today, shows you how to build your own satellite and launch it into orbit.

No, we’re not kidding, this is an actual thing you can do.

And to track the satellite you’ve launched, or another satellite you’re interested in, here’s how to build your own SatNOGS ground station with a Raspberry Pi 3B+.

Building a Raspberry Pi ground station

Once you’ve built and launched your small satellite, you’ll want to listen to all the glorious telemetry and data it‘s sending back as it hurtles around the Earth. Or perhaps you aspire to have a satellite up there, but in the meantime you want to listen to some other objects? What you need is a ground station, but a single ground station has one slight flaw. Most of the time a satellite will not be overhead of a single ground station; in fact, it may only pass over a ground station once every few days, massively reducing the amount of information or data we can receive. So we need a network of ground stations. The SatNOGS network solves this by creating a global network of stations that can work together to increase coverage.

SatNOGS is an open-source project that has numerous designs for satellite ground stations, but whichever design you pick, you can join the network that links them all via the web.

A station owner can use the website to browse for future passes of a satellite, and then click a button to schedule for their station to turn on, tune to frequency, and record the pass, sometimes even rotating the antenna on the station to track the satellite. Not only can a station owner schedule an observation on their own station, but they can schedule observations on any station on the global network.

As we can see from this map of data being collected of a recent SSTV broadcast from the ISS (sends single-frame images transmitted via audio from the ISS), the SatNOGS network has near-global coverage, rivalling most professional institutions in the world.

Simple setup

The simplest form of a SatNOGS station is one that doesn’t move or track and is made from a static antenna, a Raspberry Pi, and a cheap software-defined radio (SDR) dongle. The SDR dongle has become ubiquitous in maker circles as it is an affordable entry item into the world of receiving signals via SDR. Looking at our ingredients in the image below, let’s explore them a little more before we get started.

While a permanent station may do better connected by Ethernet cable, using the Raspberry Pi’s built-in wireless LAN functionality means we can run this simply with only a power cable. While many have used the cheapest Realtek SDR dongles with success, some people have found the slightly more refined versions can be more stable – a current recommendation is the RTL-SDR V3, which has a better casing for thermal dissipation, and slightly upgraded components. The RTL-SDR V3 is available here.

The classic antenna recommended for a static SatNOGS setup shown above is a ‘turnstile’ antenna; commercial models are available, such as the Wimo TA-1, but people have designed and built lots of different static antennas for different frequencies and with small budgets – check out the tutorial Make a Slim Jim antenna on page 112 (in HackSpace issue 18, links below).

In order to set up a ground station, one of the first tasks we need to do is set up an account on network.satnogs.org. Registering on the site then gives us a dashboard where we can begin to set up a station. Click to add a station — we then need to supply it with some basic details as per the image below: a name for the station, a location in latitude and longitude (Google is your friend here!), and the elevation of the station above sea-level.

You need to decide what frequency your station is going to cover; the most common ranges are UHF and VHF, which would require different antennas, but either range has a huge number of objects you can schedule to observe. Many people opt for VHF, as this includes the frequency range for a lot of the different transmissions from the ISS, so we are going to choose VHF as well. You also need to add a minimum elevation value — this is the minimum angle that a satellite must be in terms of height for your station to see it — if you aren’t sure, either ask for help on the forums, or leave it for now at the default 10 degrees.

Having filled in the boxes to create the station (leave the ‘this is in testing’ box ticked for now), you should now see a ground station entry has been made on your account, as above. You will see (even though it isn’t set up yet) a list populating underneath the entry with ‘Pass Predictions’, which are things you could schedule to observe once you are up and running. Before we leave the website, we need to make a note of the number assigned to the ground station, and also our own personal API key — which we can find in our dashboard by clicking the API key button. These two pieces of information are what will ultimately connect our ground station hardware to the website account.

The next task is to sort out the Raspberry Pi. You can find the current custom SatNOGS image here.

Flash this to your microSD card as you would for a regular Raspberry Pi setup — the free app Etcher, for example, is a simple tool that allows you to flash an image to a card.

Once done, boot the Raspberry Pi, and you can either SSH into the Pi, or connect a keyboard and monitor and interact with the setup that way. The first things we need to do are not SatNOGS-specific, but are the usual things we do when setting up a Raspberry Pi. We need to set up a different password by running the sudo raspi‐config command. Once you’ve set a password and expanded the file system, it’s also useful to set the time zone to UTC, as this is used throughout the SatNOGS network. If you want to run this test station wirelessly, then you need to configure your network connection at this point. If you are connecting via an Ethernet cable, then you don’t need to do anything else. Apply the changes and reboot (then see ‘Final setup’ box above in HackSpace issue 18, links below).

Now, if we go back to our dashboard on the SatNOGS website (perhaps wait a few minutes and click Refresh), we should see that the station is now online, as above. We should see an orange spot on the network map showing our proud station in testing. Being in testing means that only you can schedule observations on the station, but when you are ready, you can change settings to take it out of testing and then it is fully on the network.

On the hunt

Power down one last time and connect the RTL-SDR dongle and the antenna, then reboot — you are now ready to hunt satellites! Scheduling observations is as simple as selecting passes from the list and clicking Schedule. There may be drop-down choices for different transmitters to listen for on the same satellite, and other choices, but essentially you click Calculate to create the observation and then Schedule for the job to be created and sent to the queue for your station. There are hundreds of satellites to try to observe, so don’t worry if you don’t understand what any of them are — in the pass predictions list, if you click the name of a satellite you will get a pop-up with information about it. For a more detailed walkthrough of scheduling an observation on the SatNOGS network, check out this blog post.

After the time of the pass, return to the observation page and, hopefully, you should see some signals. Don’t worry if your first few observations aren’t successful: try at least a dozen observations before making any changes, as there are many possible reasons for a signal not getting picked up; indeed, the satellite may not even have been transmitting. If you have received a signal, you should ‘vet’ the observation as good; this is particularly important if you have scheduled on someone else’s station – etiquette says we should check and vet our own observations. Check out the Slim Jim antenna (see page 112 of HackSpace magazine issue 18, links below) for a link to a successful observation you can listen to.

Happy satellite hunting!

Finally, it’s a great idea to join the Libre Space Foundation community forum (or IRC), as it hosts the SatNOGS community channels, and there is a wealth of expertise and help available there from a very welcoming community. If you build a station, go and share your achievement on the forum — everyone will be pleased to see it.

Get HackSpace magazine issue 18 — out today

HackSpace magazine issue 18 is out today, and available online, or from many high-street retailers such as WHSmith and Sainsbury’s in the UK, and Barnes & Nobel in the US.

You can also download issue 18 for free, today as a PDF, so there really is no reason not to give HackSpace a spin.

The post Build a SatNOGS ground station with a Raspberry Pi 3B+ | HackSpace magazine #18 appeared first on Raspberry Pi.

Beowulf Clusters, node visualisation and more with Pi VizuWall

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/beowulf-clusters-node-visualisation-pi-vizuwall/

Pi VizuWall is a multi-Raspberry Pi MPI computing system with a difference. And the difference is servo motors!

Pi VizWall at Maker Faire Miami

We can thank Estefannie for this gem. While attending Maker Faire Miami earlier this month, she shared a video of Pi VizWall on her Instagram Stories. And it didn’t take long for me to ask for an introduction to the project’s owner, Matt Trask.

I sent Matt a series of questions in relation to the project so I could write a blog post, but Matt’s replies were so wonderfully detailed that it seems foolish to try and reword them.

So here are the contents of Matt’s email replies, in their entirety, for you all to enjoy.

Parallel computing system

The project is a parallel computing system built according to the Beowulf cluster architecture, the same as most of the world’s largest and fastest supercomputers. It runs a system called MPI (Message Passing Interface) that breaks a program up into smaller pieces that can be sent over the network to other nodes for execution.

A Beowulf cluster at Michigan Tech

Beowulf clusters and MPI were invented in 1994 by a pair of NASA contractors, and they totally disrupted the high-performance computer industry by driving the cost of parallel computing way down. By now, twenty-five years later, the Beowulf cluster architecture is found in approximately 88% of the world’s largest parallel computing systems.

Going back to university

I’m currently an undergraduate student at Florida Atlantic University, completing a neglected Bachelor’s Degree from 1983. In the interim, I have had a wonderful career as a Computer Engineer, working with every generation of Personal Computer technology. My main research that I do at the University is focused on a new architecture for parallel clusters that uses traditional Beowulf hardware (enterprise-class servers with InfiniBand as the interconnect fabric) but modifies the Linux operating system in order to combine the resources (RAM, processor cores) from all the nodes in the cluster and make them appear as a single system that is the sum of all the resources. This is also known as a ‘virtual mainframe’.

The Ninja Gap

In the world of parallel supercomputers (branded ‘high-performance computing, or HPC), system manufacturers are motivated to sell their HPC products to industry, but industry has pushed back due to what they call the “Ninja Gap”. MPI programming is hard. It is usually not learned until the programmer is in grad school at the earliest, and given that it takes a couple of years to achieve mastery of any particular discipline, most of the proficient MPI programmers are PhDs. And this, is the Ninja Gap — industry understands that the academic system cannot and will not be able to generate enough ‘ninjas’ to meet the needs of industry if industry were to adopt HPC technology.

Studying Message Passing Interface

As part of my research into parallel computing systems, I have studied the process of learning to program with MPI and have found that almost all current practitioners are self-taught, coming from disciplines other than computer science. Actual undergraduate CS programs rarely offer MPI programming. Thus my motivation for building a low-cost cluster system with Raspberry Pis, in order to drive down the entry-level costs.

This parallel computing system, with a cost of under $1000, could be deployed at any college or community college rather than just at elite research institutions, as is done [for parallel computing systems] today.

Moving parts

The system is entirely open source, using only standard Raspberry Pi 3B+ boards and Raspbian Linux. The version of MPI that is used is called MPICH, another open-source technology that is readily available.

Perhaps one of the more interesting features of the cluster is that each of the Pi boards is mounted on a clear acrylic plate that is attached to a hinging mechanism. Each node is capable of moving through about 90 degrees under software control because a small electric servo motor is embedded in the hinging mechanism. The acrylic parts are laser-cut, and the hinge parts have been 3D printed for this prototype.

Raspbian Linux, like every other Linux version, contains information about CPU utilization as part of the kernel’s internal data. This performance data is available through the /proc filesystem at runtime, allowing a relatively simple program to maintain percent-busy averages over time. This data is used to position the node via its servo, with a fully idle node laying down against the backboard and a full busy node rotating up to ninety degrees.

Visualizing node activity

The purpose of this motion-related activity is to permit the user to visualize the operation of the cluster while executing a parallel program, showing the level of activity at each node via proportional motion. Thus the name Pi VizuWall.

Other than the twelve Pi 3s, I used 12 Tower Pro micro servos (SG90 Digital) and assorted laser-cut acrylic and 3D-printed parts (AI and STL files available on request), as well as a 14-port Ethernet switch for interconnects and two 12A 6-port USB power supplies along with Ethernet cable and USB cables for power.

The future of Pi VizuWall

The original plan for this project was to make a 4ft × 8ft cluster with 300 Raspberry Pis wired as a Beowulf cluster running MPICH. When I proposed this project to my Lab Directors at the university, they balked at the estimated cost of $20–25K and suggested a scaled-down prototype first. We have learned a number of lessons while building this prototype that should serve us well when we move on to building the bigger one. The first lesson is to use CNC’d aluminum for the motor housings instead of 3D-printed plastic — we’ve seen some minor distortion of the printed plastic from the heat generated in the servos. But mainly, this will permit us to have finer resolution when creating the splines that engage with the shaft of the servo motor, solving the problem of occasional slippage under load that we have seen with this version.

The other major challenge was power distribution. We look forward to using the Pi’s PoE capabilities in the next version to simplify power distribution. We also anticipate evaluating whether the Pi’s wireless LAN capability is suitable for carrying the MPI message traffic, given that the wired Ethernet has greater bandwidth. If the wireless bandwidth is sufficient, we will potentially use Pi Zero W computers instead of Pi 3s, doubling the number of nodes we can install on a 4×8’ backboard.

The post Beowulf Clusters, node visualisation and more with Pi VizuWall appeared first on Raspberry Pi.

Raspberry Pi-controlled brass bell for ultimate the wake-up call

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/raspberry-pi-controlled-brass-bell-for-ultimate-the-wake-up-call/

Not one for rising with the sun, and getting more and more skilled at throwing their watch across the room to snooze their alarm, Reddit user ravenspired decided to hook up a physical bell to a Raspberry Pi and servo motor to create the ultimate morning wake-up call.

DIY RASPBERRY PI BELL RINGING ALARM CLOCK!

This has to be the harshest thing to wake up to EVER!

Wake up, Boo

“I have difficulty waking up in the morning” admits ravenspired, who goes by the name Darks Pi on YouTube. “My watch isn’t doing its job.”

Therefore, ravenspired attached a bell to a servo motor, and the servo motor to a Raspberry Pi. Then they wrote Python code in Raspbian’s free IDE software Thonny that rings the bell when it’s time to get up.

“A while loop searches for what time it is and checks it against my alarm time. When the alarm is active, it sends commands to the servo to move.”

Ouch!

While I’d be concerned about how securely attached the heavy brass bell above my head is, this is still a fun project, and an inventive way to address a common problem.

And it’s a lot less painful than this…

The Wake-up Machine TAKE #2

I built an alarm clock that slapped me in the face with a rubber arm to wake me up.I built an alarm clock that wakes me up in the morning by slapping me in the face with a rubber arm.

Have you created a completely over-engineered solution for a common problem? Then we want to see it!

The post Raspberry Pi-controlled brass bell for ultimate the wake-up call appeared first on Raspberry Pi.