Schlagwort: tech articles

  • Photon: A DIY incident light meter

    Photon: A DIY incident light meter

    Reading Time: 3 minutes

    Pico power

    While most modern digital cameras have light meters built-in, many older cameras don’t have this luxury, and the price of some light meters can be prohibitive. Enter Martin Spendiff and Vanessa Bradley, two familiar makers who present their latest Pico-based project: Photon, a very budget-friendly take on this handy tool. Always keen to use old tech whenever possible, and aware of a revival using analogue film, the pair show off their make in this slick YouTube video.

    The duo felt that “the big brand light meters seemed too expensive for what they actually are.” Also, this is a potential money-saver if you use film in your camera, as “film is still pretty expensive, so something that means more consistent images is really useful.” Furthermore, Martin is now very conscious that, “after using Picos for a while, you look at things and think ‘I could build that’!”

    Photon contains a light sensor which reads the light level and then “does a little bit of calculation to make it able to turn that into the required camera settings. Pico is doing all the hard work with a bit of MicroPython that we put on GitHub,” explains Martin. The code was “borrowed from some other projects (coffee grinder augmentation and the burger cooker); it isn’t very complicated code, so it was pretty easy to cobble together.”

    Proof of the pudding

    To make sure that Photon was performing as it should, a consistency check was done against much more expensive counterparts, and the results were hugely encouraging. So much so that Martin admits being surprised: “When I saw that people were saying they were building them, I nervously went back and rechecked against a couple of expensive meters and a grey card and a camera… it was accurate over a wide range of light levels. It was a relief!

    “The feedback has largely been from the analogue film community, and positive,” he continues. “I think the overlap between makers and keen photographers is bigger than we anticipated.” Martin alludes to a famous photography expression, attributed to the New York photographer Weegee, which is ‘f/8 and be there’, the underlying gist of which is: take the opportunity for a great picture, but don’t worry too much about technique, using a basic aperture setting. “The incident meter is a good way to simplify the process of getting a good exposure. My photos aren’t better, but they are definitely more consistent,” affirms Martin.

    Regular readers of The MagPi will remember other Veeb projects we’ve featured, and Martin thinks he may now want to go back and “refactor” some of those soon. “There have been lots of times where we learned things and thought… we should have done X like that,” and Photon might be a project that gets some future refactoring once more GitHub feedback is received. You can find their collection of superbly put together and illuminative videos on Veeb’s YouTube page.

  • Galactic Unicorn (Pico W Aboard) review

    Galactic Unicorn (Pico W Aboard) review

    Reading Time: 3 minutes

    When you first power on the Galactic Unicorn, via the supplied short micro-USB cable, it immediately springs into life with Pimoroni’s MicroPython firmware and code examples pre-installed, so there’s no need to flash it. Text on the display invites you to press the A, B, C, or D button to launch a different graphical demo.

    Whichever button you select, you’re sure to be impressed. There’s a cool (or rather warm) burning flames effect, an eighties supercomputer (random pixels), a cycling rainbow, and a nostalgia computer prompt. What you notice straight away is how these pixels are large and bright (dazzling at the maximum level) – and there’s no sign of flicker, even if you film the display running. The Pico W RP2040’s PIO state machines are used to drive the LEDs at around 300 fps at 14-bit resolution, while gamma correction is applied to image data.

    Button controls

    Those four tiny tactile buttons are situated on the rear, along with five others on the opposite side to sleep the display, adjust the brightness, and alter the volume from the mini 1 W speaker on the rear. They’re also labelled on the front of the board for easy reference so you can reach behind to press them. In addition, there’s a handy reset button on the rear to reboot the device.

    Also on the back, along with some nifty silkscreen artwork, you’ll find an optional battery connector (for up to 5.5 V) and a couple of Qwiic/STEMMA ports (JST-SH) for connecting breakouts such as sensors. The Galactic Unicorn even has one sensor built-in: a phototransistor at the right-hand edge of the front panel to detect light levels – which could be useful for adjusting the display brightness automatically.

    While the LEDs have some built-in diffusion, you may want to add your own diffuser panel, in which case the mounting holes should come in useful. Example DXF files are supplied on the product page. To stand the board vertically, at a slight angle, two metal legs are supplied and screw into any of four slightly larger holes in the board edge.

    Pixel programming

    Programming the Galactic Unicorn should prove relatively easy in MicroPython. Several further code examples are supplied on the GitHub repo. These include a fairly convincing, procedurally generated lava lamp and an easily adaptable scrolling text demo. Graphics and text are generated using the PicoGraphics library – used for several of Pimoroni’s displays, it offers rich functionality including shapes, sprites, and a selection of fonts. Other functions are explained in the Galactic Unicorn reference guide.

    There are a few examples that make use of Pico W’s wireless connectivity too. Just pop your Wi-Fi network details into the WIFI_CONFIG.py file to get connected. A digital clock demo fetches the live time from an NTP server; a Cheerlights history slowly builds up coloured pixels, one every five minutes; while a Galactic paint program enables you to draw on the display in real-time from another device via a web server hosted by Pico W – very cool indeed!

    With a little creativity, there’s the potential to use the Galactic Unicorn for a wide range of projects, including wireless ones such as a live weather dashboard or scrolling RSS feed.

    Verdict

    9/10

    Its elongated shape may not suit all projects, but this is one dazzling display that makes uses of Pico W’s power to create impressive animated effects at a super high frame rate.

    Specs
    Display: 53×11 matrix of RGB LEDs (583 in total)
    Features:
    Pico W on board, 10 × push-buttons, mono I2S amp and 1W speaker, 2 × Qwiic/STEMMA ports, battery connector, 2 × metal legs
    Dimensions:
    331 × 79 mm

  • Smart camera

    Smart camera

    Reading Time: 2 minutes

    Similar things can be said about text generators like ChatGPT. We’ve seen people use it to create a jumping on point for simple Python code, which is an interesting use of open-source scripts. However, for actual text… well, the best way I’ve seen it described is ‘confidently wrong’. For very basic stuff, you might get something competent, but anything else and it’s better to get a person involved.

    Computer vision

    Over the years, we’ve made great use of OpenCV in many Raspberry Pi projects – it’s a machine learning tool that processes image data to help make decisions. It’s used in robotics a lot with a Raspberry Pi Camera Module, with the late, great Formula Pi robots doing stellar work with it as they zipped around.

    This use of AI is great. It’s doing something people can sort of do, but if you were doing these tasks it would be a bit menial. And the AI can do it a lot faster.

    I’ve also seen people use image recognition technology with Raspberry Pi to create a Pokédex from the Pokémon anime – a device that recognises the eponymous monsters – and simply a ‘magic wand’ that identifies what it’s being pointed at. Both work to varying degrees of success. However, humans only know a limited amount of knowledge too.

    Ethical future

    We’re currently at a tipping point with a lot of AI tech. It’s getting very interesting and very powerful, but the technology should not be replacing human expression – especially when it’s copying other humans’ expressions without any context. The way it’s been used in computer vision is a good template for the future – as an aid and not a pseudo-replacement. Art is important expression after all.

    With the new Camera Module 3 and its laundry list of new features, I can only imagine what we’ll be able to do with it that a person cannot.

  • PiRitos Star Trek interface

    PiRitos Star Trek interface

    Reading Time: 2 minutes

    This means if you really want to do some light Star Trek roleplay, you can have several screens in one room which have some degree of connectivity – such as displaying a red alert.

    “After that, I connected LEDs to the back of my monitor and they would pulse red if the status was ‘red alert’,” James continues. “I connected a Raspberry Pi Sense HAT to the Flask server, so room weather data would be sent to the PiRitos system. Finally, for a bit of fun, I connected a Pico to the server and it transmitted its own internal temp sensor reading to the Flask server. This was also sent to all the connected clients.”

    Isolinear processing

    The project itself started solely as Ritos in the browser but, after seeing it in action, James asked meWho Rob if he could have the source code to make PiRitos. He used it as an excuse to learn Flask and Socket.IO, as he reckons he learns best via a project.

    “meWho Rob decided to help me for a few weeks, and we managed to work together to open some of the JS functions and attached the Socket.IO code,” James explains. “After that, it was a simple case of having Flask and Socket.IO communicate to the connected clients. Once communication between server and client was working, it was super-easy to extend to physical hardware like LEDs and sensors.”

    Second contact

    The result is fantastic – we mentioned it in our previous issue after it got shared far and wide on social media, with many Raspberry Pi and Star Trek fans getting excited by the project.

    “At the moment, I don’t think I have any plans to do anything more with the PiRitos system,” James admits. “It’s been a bit of fun and a great learning experience, but it would take a lot of work to get this into something more useful. Personally, I want to tinker more with connecting Raspberry Pi with other smart services like turning on/off smart plugs and lights. This could go into PiRitos at some point. Or the reverse, getting a voice assistant, like Alexa, to set the red alert status would be awesome, but [we] don’t have any road map for that… I know [meWho Rob is] moving on to make a LCARS site based off the Picard series, and maybe we can work on getting that to also work with Raspberry Pi!”

  • Deep focus on the Camera Module 3 in The MagPi magazine issue #126

    Deep focus on the Camera Module 3 in The MagPi magazine issue #126

    Reading Time: 2 minutes

    Introducing Camera Module 3 for Raspberry Pi

    Everything you need to know about the new 12-megapixel camera module with HDR and lightning-fast autofocus. Our feature is packed with starter advice, engineering insights and project ideas.

    Create Smart Lights with Raspberry Pi

    Create smart lights

    Use Raspberry Pi and Pico to light up your home. This feature covers NeoPixels, motion-sensing lights, and how to control HUE lights with Raspberry Pi. Get inspired by some of the best light show projects around.

    PiRitos: Star Trek computer interface on Raspberry Pi

    Build a Star Trek-style computer

    Discover how PiRitos has been used by one maker to lovingly recreate the LCARS computer from Star Trek. The computer is run from a Raspberry Pi server and displays on multiple screens around one maker’s home.

    Raspberry Pi Exoskeleton

    A Raspberry Pi Exoskeleton

    Learn about a Standford University program using Raspberry Pi to build a groundbreaking walking aid. This exoskeleton is made from carbon fibre and aluminium and uses machine learning to adapt to its user.

    Create a toy Chatter Box with Raspberry Pi Codec Zero

    Create a toy Chatter Box

    Make use of the new Raspberry Pi Audio boards to build a device that records short audio clips and plays them back.

  • Win one of ten Raspberry Pi Camera Module 3

    Win one of ten Raspberry Pi Camera Module 3

    Reading Time: < 1 minute

    Subscribe

  • Get creative with Raspberry Pi Pico

    Get creative with Raspberry Pi Pico

    Reading Time: 2 minutes

    Fiber OpticMatrix Display

    Using LEDs such as NeoPixels is a pretty easy thing to do – we’ve covered them extensively in issues 122 and 123 with light-up vacuum cleaners and Christmas tree lights. This project (which we covered in issue 118) goes further, using optic fibres connected to an LED board to create beautiful glowing effects, as text and images are pushed through them to a ‘screen’. It’s mesmerising in motion, and is truly a conversation starter. It’s a little time-consuming though – there are about 250 optic fibres hooked between the LEDs, and the display and programming them is a little different than a standard uniform display. At least you’ll have a head start on the code from maker elliotmade.

    magpi.cc/fomatrix

    Light painting

    Light painting is a bit of a trick – you’re not actually painting with light, you’re just using maths and a long exposure time to create something that only exists in camera. However, it is an exceptionally cool existence. You can do it with bikes with lit-up spokes, special LED strips, and much more to make incredible stuff.

    magpi.cc/lightpainting

  • Make sound with Pico

    Make sound with Pico

    Reading Time: 3 minutes

    Pico Portal Music Box

    Even after 15 years, Portal’s Still Alive song is still well remembered and this project will make sure you never forget it. Pico can actually play MP3 files, and maker thisoldgeek wanted to give it a more antique music box vibe, so he created one in the style of a music box MIDI sound. It’s still an MP3 though!

    He reckons it takes a couple of hours to put together, with a simple 3D-printed box and minimal amount of soldering and wiring required. It even includes lights, which fade in and out for a great effect.

    Pico Audio Pack

    Instead of soldering a speaker to your Pico, this add-on allows you to have high-quality audio output from Pico through 3.5 mm jacks. It connects to Pico like a HAT on Raspberry Pi. You can even choose to manually amplify each output. Grab one here.

    Pico Piano

    This clever project uses a copper-plated board with piano keys etched into them and a series of resistors to create variable currents at each key. The piano player then uses a jumper cable hooked up to a Pico which senses the different current values and plays a note based on it.

    This use of resistors would be very difficult to do on Raspberry Pi without other components. If you don’t have access to copper boards and etching solutions, you can use a perf board as well to create a piano.

    MIDI controller

    There are a couple of great DIY MIDI controller projects for Pico – we quite like the MIDI Fighter that uses arcade buttons – however, if you just want to experiment with code and don’t want to do too much physical building, Keybow 2040 from Pimoroni is a great customisable keyboard that can be used as a MIDI controller with some coding. Get it here.

    Lo-Fi Orchestra

    This massive orchestra is made up of various microcontrollers and microcomputers, and nearly every week we get to hear something new from it. We quite like the version of Gustav Holst’s The Planets suite composed on it. You can find out how it works with the very thorough blog.

  • RelayFi smart relay board review

    RelayFi smart relay board review

    Reading Time: 2 minutes

    The four relays take up most of the board and handle conversion and control for four mains-powered devices. We highly suggest getting some kind of case for the board as there are solder points on the underside of the PCB. These relays are controlled via an optoisolator which does improve the safety of the relays and, despite there being four squeezed onto the board, the screw terminals have a decent amount of space between them. Still – caution is recommended with this, like any other relay.

    Connecting to things

    With a series of I2c and standard component pins, you can add a little extra control to the board that is all programmed using the classic Arduino IDE. As it’s all Wi-Fi connected, having it talk to a Raspberry Pi or Pico W is a matter of making sure it’s looking for the right thing. Like an Arduino board, a micro USB port is used to power and connect to it for programming, which also supports various smart home systems for voice control via RelayFi.

    It’s a fairly solid build for such a relatively cheap board, and the ease of coding helps with its appeal as well.

    Verdict

    7/10 A solid IoT board with easy programming functions that can interact with Raspberry Pi just fine.

    Specs

    Microcontroller: ESP32
    Connectors:
    Relays × 4, 5 × 3 component pins, I2c breakout, USB micro data port
    Radio:
    Wi-Fi, Bluetooth 4.2, BLE

  • What we achieved in 2022

    What we achieved in 2022

    Reading Time: 2 minutes

    For 2022, I decided to make some goals and rough plans instead of stumbling into projects like I have in the past – and also promising to go a bit easier on myself if I didn’t achieve them all.

    Still stumbling

    One thing I’m always proud of is the work we do on The MagPi. I’m especially happy when I get to make something cool and talk about what I’ve learnt in the pages of the mag – this year, in particular, three projects stand out to me.

    Firstly, there were the quiz button boxes. After years of saying I’d make it, I finally created custom buzzers with programmable sounds and the ability to find out who pressed buttons in what order. I’ve made some modifications since I put the tutorial in the mag and, at some point, I’ll update the code on the GitHub as well.

    Otherwise, this year I got back to making cosplay props with the Poltergust G-00 I made with help from, 3D printing wizard and Raspberry Pi Maker in Residence, Toby Roberts. It was a bit easier than last time when I had to gut a real vacuum cleaner, and I learned a lot about using NeoPixels with Pico, which I then applied to some excellent Christmas lights that are shortly going up on my tree.

    Satisfaction guaranteed

    Other things I planned for the year – mostly personal stuff like make silly videos and write more fiction – I wasn’t always able to get to, but thankfully I did enough to be proud of. Maybe I also was able to be kinder to myself in the process as well!

    Anyway, I hope you all have a fantastic 2023. I’ll see you there.

  • Code Pico with Thonny

    Code Pico with Thonny

    Reading Time: 2 minutes

    2. Choose interpreter

    Thonny is normally used to write programs that run on the same computer you’re using Thonny on; to switch to writing programs on your Raspberry Pi Pico, you’ll need to choose a new Python interpreter. Look at the bottom-right of the Thonny window for the word ‘Python’ followed by a version number: that’s your current interpreter.

    Click ‘Python’ and look through the list that appears for ‘MicroPython (Raspberry Pi Pico)’ – or, if you’re running an older version of Thonny, ‘MicroPython (generic)’.

    3. Hello World

    Writing a program for your Raspberry Pi Pico is a lot like writing a program for your Raspberry Pi. You can type commands in the Shell area at the bottom of the window to have them immediately executed, or you can write a program in the main part of the window to run on-demand.

    Click in the Shell area, next to the >>>> symbols, and type:

    print("Hello, World!")

    When you press ENTER at the end of the line, you’ll see your Raspberry Pi Pico respond.

    You are now ready to start writing your MicroPython code in the main window. Click Run to start the program on Raspberry Pi Pico. Take a read of our book, Get Started with MicroPython on Raspberry Pi Pico if you want to learn more about Pico programming.

    Top tip: Update Thonny

    If you don’t see ‘MicroPython (Raspberry Pi Pico)’ in the interpreter list, you’ll need to update Thonny. Open a Terminal window and type:

    sudo apt update && sudo apt full-upgrade -y
  • Set up Raspberry Pi Pico

    Set up Raspberry Pi Pico

    Reading Time: < 1 minute

    2. Switch to MicroPython

    Raspberry Pi Pico is set up, by default, for use with the C/C++ Software Development Kit (SDK). The C/C++ SDK is an extremely flexible and powerful way to interact with your Raspberry Pi Pico. However, there’s a more beginner-friendly method: MicroPython.

    Hold down the small button on your Raspberry Pi Pico marked ‘BOOTSEL’ and connect Pico to your computer using the USB cable. (We are using a Raspberry Pi). Wait a few seconds, then let go of the BOOTSEL button. You will see your computer mount a removable drive. Click OK in the ‘Removable medium is inserted’ window to open Raspberry Pi Pico’s on-board storage.

    3. Install the UF2 firmware

    Double-click the INDEX.HTM file shown in Pico’s mounted storage. Your browser will open and display the Raspberry Pi Documentation web page. Select ‘MicroPython’, then click the option to download the correct MicroPython firmware for your board (Pico or Pico W). It’s a small file, so it’ll only take a few seconds.

    Open File Manager and locate the.uf2 file in the Downloads folder. Drag-and-drop the UF2 file to the Raspberry Pi Pico’s removable drive (named ‘RPI-RP2’). After a few seconds, the drive will disappear as the new MicroPython firmware is recognised and installed.

    You’ll need:

  • PiCar entertainment system

    PiCar entertainment system

    Reading Time: 3 minutes

    “I have made extensive modification to my Jeep, including replacing the motor with a Chevy LS 6.0 V8,” Vincent tells us. “This required some hacking into the Jeep’s CAN bus to fool the Jeep into thinking it still has a motor. There is so much useful information present on the network that is not presented to the driver, and it frustrated me that one of the main user interfaces on the vehicle, the car radio, does not present or allow the driver to access it.”

    Vincent looked at various solutions, but they didn’t quite fit the Jeep’s aesthetic. He decided to make something a bit more custom using a VFD (vacuum fluorescent display) to fit the original look, and even fool folks into thinking it was the stock radio.

    Farm to auto

    After using Raspberry Pi to fix an automated chicken coop, Vincent started using it more in projects.

    “I found that it was fairly easy to use Raspberry Pi to interface to the CAN bus as well as I2C,” Vincent explains. “Since it was a Linux-based platform, it was also easy to talk to the various software-defined radio (RTL-SDR) devices out there.”

    Even with a familiarity with Raspberry Pi, and ease of access to the interfaces, the project hasn’t been without issues.

    “It has been a learning experience,” Vincent says. “While there are a lot of folks building things for Raspberry Pi, not a lot of the software or hardware is rugged enough to put in an automotive application. A lot of tools, while pretty cool, were written at the hobbyist level. For instance, most of the software-defined radio (SDR) tools require a desktop display, and can’t be used in a car radio app.

    “The other problem was that the automotive manufacturers are really proprietary and secretive about how their systems work. I had to mostly adjust the Jeep CAN network packet information by trial and error, such as monitor the packets, open a car door, and see what changes, etc.”

    In the end, Vincent wrote a custom application in C++ that talks to the VFD over the serial port. It monitors the states of the knobs and the CAN bus, talks to a GPS board via serial, and the SDR via USB.

    Finishing touches

    “[It’s] just about ready to replace the existing radio,” Vincent tells us. “I am currently alternating between it sitting on my shop desk and my dashboard. I have a temporary harness cabled that allows me to plug it [in] and move it back and forth. I need to paint and engrave the faceplate.”

    Apparently reactions have been varied – folks who know what he’s made are blown away while others are at least appreciative of the display. Count us in as one of the blown-away parties.

  • reTerminal E10-1 industrial expansion board review

    reTerminal E10-1 industrial expansion board review

    Reading Time: 2 minutes

    We do mean beefy too – it’s larger than the original reTerminal, and attaching it does increase the footprint (and weight). However, for that sacrifice you do get a barrel DC jack, a battery compartment, PoE, improved wireless LAN, mobile network support, serial ports, microphones, and speakers for any machine learning application, and the ability to add much more storage via SATA 2.0 and M.2 drives.

    Safely secured

    Adding storage isn’t just a case of slotting in an SD card – the whole expansion kit comes apart so that you can install any drives into the very sturdy case so you’re not losing any protection. The battery compartment is attached by screws as well, so any portable power you put in won’t accidentally fall out.

    Attaching the expansion to reTerminal is very easy – it slots into a port covered by a rubber foot on the rear end, and is then secured with a couple of provided screws. No friction or plastic clasps are used so there’s no danger of the connector wearing out, so to speak.

    With that connection, you just need to install a driver and a Python library to the main reTerminal and you’re ready to go and incorporate the expansion into the system. It’s very easy and will definitely help with connecting to older hardware.

    Verdict

    9/10

    A great, if bulky, expansion for reTerminal that seems to address any prior connectivity issues.

    Specs
    Connectivity:
    RS-485, RS-232, CAN, RJ45 Gigabit Ethernet, M.2, Mini-PCIe, mobile network, wireless LAN
    Dimensions: 140 mm × 95 mm × 30 mm

  • Mini Mars Rover

    Mini Mars Rover

    Reading Time: 3 minutes

    Nikodem had to fit the building of his own remote-controlled Mini Mars Rover around his other university work, and there was plenty to do, including designing it from scratch in CAD and undertaking a lot of 3D printing and CNC machining.

    “All parts were designed in such a way that you can print them on the most popular FDM 3D printers and you don’t need a huge build plate,” he says. “The bottom plate was machined on my DIY CNC machine – IndyMill… The principle of how it works is very simple; designing and 3D printing it is not.”

    He also kept adding more features while working on the project. In particular, the robotic arm was an especially time-consuming part, with Nikodem designing and then redesigning it multiple times until it worked. The 3D printing aspect took around 24 hours in total but, in the end, all parts worked beautifully.

    Core components

    Raspberry Pico W is integral to the Rover: “Thanks to Pico W, it is possible to control it through Wi-Fi and [a] simple Python script on a computer,” explains Nikodem. The script is created with Pygame and a simple custom class he developed for the simple user interface elements he needed.

    “For controlling the micro servo motors, I am simply using 50Hz PWM signal. For DC motors I am using popular and cheap drivers, L298N, and control them through PWM and digital pins,” he explains. He also added an FPV camera system to the build, which turned out to be far simpler than he’d imagined. “I had no experience with FPV systems before; it was completely new to me, but it turned out to be super-straightforward and it works great.”

    Small and sharable

    Nikodem was determined to make his project as clean and small as possible “for aesthetics reasons, but also for its safety and functionality,” he underlines. He also wanted to be able to share his work with others and make it easy to replicate, so he chose to make his own custom PCB, using a cheap CNC machine he’d modified. “The best part about this setup is: in the morning I design a PCB and, by the afternoon, I have it ready for soldering.”

    Nikodem’s Rover has received plenty of positive comments and he admits “that was a big relief after working on it for so long.” There were a few people who suggested that the Rover’s wheels wouldn’t survive the Mars environment, but Nikodem is pragmatic as “it was quite obvious for me from the beginning that the purpose of the project is to educate and inspire. Building it in the way real Mars rovers are built is completely unrealistic and unnecessary.”

    Excitingly, Nikodem is now concentrating on his bachelor thesis project which will use Pico’s RP2040 chip. “I am currently testing the PCB for the project… The end goal is to be able to take long exposures of deep sky objects with a camera by compensating the movement of Earth and also create a go-to system with Stellarium.”

    If you take a look at Nikodem’s YouTube channel, you’ll see a huge and interesting array of projects he’s worked on so far, and it seems there will be plenty more to come from this very talented maker.

  • Meet Jeff Geerling: YouTuber, ex-engineer, maker

    Meet Jeff Geerling: YouTuber, ex-engineer, maker

    Reading Time: 3 minutes

    “And sometimes you accidentally short a computer’s power supply and end up with a burn on your finger and a dead computer!”

    When did you first learn about Raspberry Pi?

    I remember reading about the first board on Ars Technica in early 2012. I bought my first Raspberry Pi (a Model B) on September 12, 2012, and gave it to my brother a few years later, after I started using Raspberry Pi 2 for my experiments.

    How did your YouTube career get started?

    I started making videos in the late 1990s, mostly for family and friends on my old Power Mac. In 2006, I started posting a few of my home videos on YouTube – a couple are still live today! I didn’t dedicate much effort to YouTube until the pandemic. I had a bit of luck with a live-stream series I did called ‘Ansible 101’, along with some videos about building a Kubernetes cluster with Raspberry Pi computers, and my channel grew quickly.

    I calculated what kind of viewership I would need to make producing YouTube videos a viable business plan, and once I hit those numbers, I stopped doing software consulting. I make a lot less than I used to, but it’s enough. It sustains my family of six and pays the medical bills – I have Crohn’s disease and it can be difficult having a chronic illness!

    What are some of your favourite Raspberry Pi projects that you have made?

    After the Compute Module 4 came out, I had a dream to build a one petabyte Raspberry Pi – one single Raspberry Pi with a 1PB storage volume directly attached. And I did it! That project took more than two years to pull off, and required help from Broadcom engineers, Raspberry Pi engineers, and 45Drives, a storage company. It’s terribly impractical and barely worked, but it was the most fun I’ve had with a Raspberry Pi.

    My second favourite is a slapped-together Raspberry Pi ‘Red Shirt Jeff’ detector that used AI to blast Red Shirt Jeff with my leaf blower when he came into my office. I learned a bit on that project, but what made it enjoyable is how much my kids loved it. Seeing their uncontrolled laughter when the contraption worked the first time made that project much more memorable.

    What Raspberry Pi projects do your audience love?

    According to YouTube statistics, people love Raspberry Pi clusters, or ‘brambles’, as I call them. It started with the ‘Dramble’ (a Raspberry Pi cluster running the Drupal website pidramble.com since 2014), and now I’ve built a number of clusters to run Kubernetes, K3s, and even run the Linpack benchmark to see where my Pi 4 cluster ranked in the Top 500 Supercomputer list (it would’ve been competitive back in 1999)!

  • Raspberry Pi Pico Plant Waterer

    Raspberry Pi Pico Plant Waterer

    Reading Time: 3 minutes

    For Vanessa Bradley and Martin Spendiff, collectively known as VEEB, the scenario came up because their “lovely” neighbour sometimes watered their houseplants, but the plants didn’t always survive the experience. To save any more plants dying, they designed a carefully calibrated mechanism that would test whether the soil was dry enough for the plant to need watering, provide “a squirt” if needed, then check whether more moisture was required and apply it. Raspberry Pi was an obvious choice as they’d built a number of projects based on it before, some of which we’ve covered previously in The MagPi.

    Vanessa originally worked in IT and Martin as a scientist, but they were “a bit bored” of their professions and became photographers instead. Their respective technical backgrounds and flair for visuals took off during lockdown, documenting their creations at veeb.ch. “We always had Raspberry Pi computers dotted about doing stuff. During lockdown we started building things that were a bit more involved,” Martin explains.

    He says one of the real pluses of using Raspberry Pi is documentation. They used a Pico for their plant watering project, which meant losing some of the Python libraries in the switch to MicroPython, “but there isn’t a huge leap from [Raspberry Pi] Zero to Pico and there is an elegant simplicity to a little board that just does one thing, the moment that you turn it on.”

    If it ain’t broke…

    VEEB projects tend towards the weird and slightly wacky, such as an old Teasmade linked to a Google Calendar and a Boombox Jukebox. “The general pattern that has emerged is taking some simple/older technology, linking it to newer tools, figuring out something that could be useful, making a simple proof of concept,” says Martin.

    Clive Moss the Window Box Boss, as the Pico Plant Waterer has been named, is really a revamp of a VEEB project which cooks burgers in a water bath. “It’s a pretty general-purpose controller that can be applied to various situations that require some sort of monitoring/intervention.” Aside from the switch to Pico, little hardware was needed beyond what they had lying around. Martin and Vanessa bought a cheap fish tank pump and got any extras they needed from the local hardware store.

    “We took the burger cooker, removed the screen and controls, and popped it all in a waterproof box. The only part we made was bending a paper clip to hang it on the side of a plant pot.”

    Intelligent watering system

    Watering a plant is only half the equation; the other part is checking whether the soil is sufficiently wet. As Vanessa notes, “not all types of plant require the same level of moisture.” Although the moisture sensor helps provide this information, common sense is needed too: Martin admits the first time they trialled the setup, all the water was pumped into the plant pot at once. “We were too stupid to remember that the siphon effect was a thing, so on the first run of the code we just looked puzzled as a couple of gallons of water emptied into a plant pot while the pump wasn’t even turned on.” Moving the water tank further away helped. “The distance between water source and sensor means that when it has dried out, it drops a lot of water at once. This was initially an accident, but it turns out it promotes root growth.“

  • K-9 Doctor Who companion

    K-9 Doctor Who companion

    Reading Time: 3 minutes

    The K-9 project helped Fitz fulfil an ambition to build a film replica of one of their “favourite companions to my favourite Doctor” [Tom Baker, naturally] and “to experiment with Raspberry Pi and other microcontrollers, and electronics to see how well they might replicate all the animatronic and visual features of the hero prop.”

    Fitz chose Raspberry Pi for its “powerful computer processing and video display”, and options for interfacing with the physical world, giving K-9 “some level of autonomy and AI.”

    Design cues

    Having been introduced to Raspberry Pi by a friend – who he thought was pranking him, based on the single-board computer’s name – Fitz realised it would suit his needs very nicely. “Once I realised its potential, I kept Raspberry Pi in mind for any projects I engaged in.” Raspberry Pi is “a powerful tool to do pretty much anything I can think of.”

    K-9 is the main focus of Fitz’s tinkering efforts, and the only project for which he has had to do any custom design work, since some aspects could be adapted from other people’s projects. In particular, founder of the K-9 Replica group Dave Everett had produced detailed templates and assembly guides for the animatronic dog’s body, including a basic mechanical framework, which were quickly seized on by fellow Whovian makers. Another impressive K-9 Raspberry Pi build that we’ve covered uses this template too, or you can join a dedicated builder’s Facebook group.

    Building on the original

    Fitz also made use of existing designs for the very intriguing camera and AI element that he added to K-9’s head. This is “based, in part, on the wedding photo booth by Anthony Sabatella which inspired K-9’s photo-taking abilities,” code which Fitz modified for K-9.

    “Pretty much all the electronics and most of the animatronics were designed and set up by myself,” says Fitz, who reports that the build was not complex but required “a bit of time and patience to build, program, and debug,” with integrating all the parts the most challenging aspect. “Like any project, unexpected things come up. The drive system was a bit troublesome at first and had to be totally redone. Even then, it has some directional instability that needed to be rectified with a gyro.”

    K-9 is a combination of 3D-printed parts and components sourced from online stores, including Adafruit and SparkFun. Since everything would eventually be hidden inside K-9’s body, Fitz did all his prototyping on a separate bench using a different Raspberry Pi, before transferring everything to the ready-assembled setup inside the robot. This requires some duplication of hardware, but makes life easier for a project with plenty of iterative revisions and “continuous modification and expansion.” Utilising the various GPIO connections, to both read inputs from an external trigger and to run various external devices, was a big challenge. He estimates the build took three months of fairly focused work, with some light additions over the course of the following year. After an outlay of roughly $1000, the only real running costs are for the thermal paper on which K-9 prints photos of whoever is in front of him, along with a wry take on whether they might be human or alien.

    You can see Fitz’s K-9 robot in action here. Expect a new post soon, as he’s currently working on adding voice-recognition and Pico elements.

  • Get started with Raspberry Pi in The MagPi magazine issue #125

    Get started with Raspberry Pi in The MagPi magazine issue #125

    Reading Time: 2 minutes

    Raspberry Pi QuickStart Guide

    Raspberry Pi Starter Guide

    This is no ordinary starter guide. The latest edition of The MagPi magazine is packed with pages that demystify Our QuickStart guide helps you set up the hardware and Raspberry Pi operating system. Plus a super fast primer to making projects with Python code and basic electronics.

    Get creative with Raspberry Pi

    Get creative with Raspberry Pi Pico

    Use code and components to make art, music, and much more thanks to Pico. Expand your knowledge of what’s possible with Pico to knitting, carpentry, painting and a huge range of other creative projects.

    Project showcase: K-9 from Doctor Who

    Recreating K-9 from Doctor Who

    Every month we’re amazed at the projects made by the Raspberry Pi community. This month Fitz Walker stunned us with this replica K-9 from the classic Doctor Who series. It uses the latest AI technology to detect humans from aliens.

    Maka Niu

    Deep sea underwater camera

    Maka Niu is a deep-sea underwater system made using Raspberry Pi. It can currently go 1,500 meters underwater, with plans for a 6,000-deep system. It heads down into the ocean and uses Raspberry Pi to collect video files and images, record temperature levels and return its GPS location.

    Pico Plant Waterer

    Build a Pico Plant Waterer 

    Using Pico to monitor the soil moisture level of a pot plant and squirt water into it. VEEB show us how they put together a Raspberry Pi gadget to look after their houseplants.

    Watch your fish with a Raspberry Pi camera

    Watch your fish with a Raspberry Pi camera

    We love this tutorial by PJ Evans. It uses an Entaniya waterproof case to position a camera inside an aquarium and record videos.

  • Win 1 of 10 Raspberry Pi Zero 2 W

    Win 1 of 10 Raspberry Pi Zero 2 W

    Reading Time: < 1 minute

    Subscribe

  • HandiPi: All-in-one handheld desktop computer

    HandiPi: All-in-one handheld desktop computer

    Reading Time: 3 minutes

    Richard was inspired by the PICOmputer PCB created by Peter ‘Bobricius’ Misenko. “It’s a sort of carrier board for Raspberry Pi Pico that includes a keyboard using 6 mm push-button tactile switches and a display,” he explains.

    “When I later ordered a Raspberry Pi 4 computer, I got to thinking: what if I could build a case with a screen and a keyboard? I’d still use it with a monitor, keyboard, and trackball at my desk most of the time, but I could take it with me if I wanted to go hack at a friend’s house or makerspace.”

    Snug fit

    From the start, Richard knew what he wanted. “The new unit had to be small enough to fit nicely on my workbench, and I wanted it to be battery-powered with some sort of keyboard/screen for use away from the bench,” he says.

    With this in mind, he picked a 4.3-inch touchscreen roughly the same width as Raspberry Pi 4 and, having had experience creating a portable computer based on Raspberry Pi Zero with a full-size 36-key keyboard and foldable screen, he cracked on designing a similar keyboard.

    “The focus was on keeping the size minimal and it meant I did away with the Ethernet and most of the USB ports on Raspberry Pi 4,” he adds. “But, while the screen is smaller than is comfortable for long periods of work, the 36-key keyboard works surprisingly well for thumb-typing. There was, however, a bit of a learning curve figuring out the minimum required support circuitry to make the chip function and output USB.”

    Key to success

    The custom 10 × 4 ortho keyboard incorporates a five-way directional button, and it makes use of an ATmega328 DIP IC running a version of QMK firmware. Richard has also made use of a 5000 mAh battery pack which allows HandiPi to be used as a portable for up to four hours.

    “I chose the PiSugar module for battery management because it was designed to mount under Raspberry Pi and connect to the GPIO header via pogo-pins, rather than on top as with most HATs. This let me wedge it between [Raspberry] Pi and the display, only adding a couple of millimetres to the overall design.”

    With hindsight, he’d have retained the Ethernet and double-stack USB ports. “After the work to remove them was done, I’m convinced it wasn’t worth it – using a modified Raspberry Pi 4 turned out to be just something like five millimetres thicker. I built a cutout for the Ethernet jack so it sits flush with the case bottom. Having the USB 3.0 ports would be nice and the Ethernet port could potentially come in handy.”

    Still, with a cool 3D-printed case and an original Game Boy-like styling, the overall project is immensely impressive. “For the primary use – powering my workbench computing – it’s perfect,” he says. “The second, smaller screen on the unit itself can come in handy to show little bits of info from a distance, and I’ve found it can be pretty handy to ‘borrow’ the USB-C power sometimes. The reaction has also been pretty positive and, overall, I’m definitely pleased with how it turned out.”

  • Elecrow SH080 8-inch mini HDMI screen review

    Elecrow SH080 8-inch mini HDMI screen review

    Reading Time: 3 minutes

    Elecrow’s own website suggests using this screen with a Raspberry Pi for gaming. We tested the display alongside Elecrow’s CrowPi L – itself a dedicated laptop hull that fits a full-size Raspberry Pi inside and which has an HDMI port. Rather unusually, the screen has a mini HDMI input.  Powering the screen additionally requires a mini USB to mini USB cable. This is less out of the ordinary and, at least, means the screen can be entirely powered by the hardware to which it’s connected, rather than requiring an external power source and plug. One of the more useful inclusions is an adjustable metal stand that can be used to cradle and prop up the display. The three-bar stand is hinged making it easy to angle and support the screen however you please. For the Raspberry Pi 4/400 user without a CrowPi L or laptop setup, however, hooking up this screen will require an adapter: Raspberry Pi 4 has a pair of micro HDMI ports, rather than the Elecrow’s HDMI to mini HDMI cable (with a mini HDMI port on the screen itself). These micro to mini adapters aren’t common, and it would be better if the screen itself had a more common full-size HDMI port.

    There is no touch display on this option, so this screen can’t be used to create small kiosk-style projects.

    Using the screen

    Display-wise, when used as a secondary screen, the Elecrow portable display shows whatever is on the desktop, including folders, files, and the waste basket, but useful items such as the menu bar are only shown on the primary device. The display is clear and crisp, even at lower resolution settings, with generous viewing angles. It’s easy enough to switch between screens using the Appearance editor and Preferences drop-down menu in Raspberry Pi OS. Even if you do this, however, a web page you navigate to, for example, will display only on the other screen, even if you’ve specified that both monitors should show the same content and/or set the Elecrow as the primary display.

    For entertainment duties, the maximum playback resolution of 1200 × 800  pixels combines with built-in speakers or an earphone socket. You’ll need to specify HDMI output rather than headphones by right-clicking the volume icon on-screen. Speaker sound was rather patchy, but better using earphones.

    Verdict

    7/10

    A second screen is helpful in all sorts of instances, and Elecrow’s portable version is clearly aimed at entertainment, what with its HDMI, speaker, and earphone connections. The mini HDMI connection and supplied full-size HDMI to mini HDMI cable mean you’ll need an HDMI to micro HDMI adapter for Raspberry Pi 4. That makes this quality display less useful than its bright screen and decent resolution would suggest.

    Price
    £89 / $89

    Screen specs: