The BBC has a long history of supporting technology education in schools. The BBC Micro introduced a whole generation of students to computers, and more recently the Micro:bit is teaching today’s children about embedded systems. [Michael Klements] happens to be a grown adult, but has whipped up a project using the little board to build an automatic plant watering system.
Rather than a simple timer-based system, [Michael’s] build measures soil moisture using a capacitive sensor. This has the benefit of not needing to be in direct contact with the soil as resistive sensors do, and thus the sensor can be built in a fashion that minimises corrosion. The Micro:bit reads this sensor using an analog input, and displays the moisture level using its inbuilt LED matrix as a graph. Once levels dip below a set threshold, a pump is activated to deliver water to the plant until the soil is suitably moist again.
It’s a simple project, but one that would be a great way to teach students about interfacing with pumps and sensors, as well as the basics of control systems. [Michael] also notes that further work could involve interfacing multiple Micro:bits using their onboard wireless hardware. We’ve thus far seen the Micro:bit used for everything from handheld gaming to gumball delivery. Video after the break.
It sucks that certain stuff in public is off-limits right now, like drinking fountains and coin-operated candy and gum machines — especially the fun kind where you get to watch your gumball take a twisting trip down the tower and into the collection bin. Hopefully there will be commercial contact-free machines one of these days that take NFC payments. Until then, we’ll have to make them ourselves out of cardboard and whimsy and Micro:bits.
[Brown Dog Gadgets] also used one of their Crazy Circuits Bit Boards, which is a Micro:bit-to-LEGO interface module for building circuits with conductive tape. There’s a distance sensor in the rocket’s base, and a servo to dispense the gumballs. This entire build is fantastic, but we particularly like the clever use of a LEGO Technic beam to both catch the gumball and prevent the next one from going anywhere. You can see it in action after the break.
There’s an old tale that TV companies only need to make a few years of kids’ TV shows, because their audience constantly grows out of their offerings and is replaced by a new set with no prior knowledge of the old shows. Whether it’s true or not is up for debate, but does the same apply to single board computers aimed at kids? The original BBC micro:bit was first announced back in 2015 and must be interesting its second generation of kids by now, but that hasn’t stopped them bringing out a second version of the little educational computer. How do you update such a simple device? Time to take a look.
The form factor of the new board is substantially the same as its predecessor, with the same edge connector and large connection pads, and the familiar LED matrix display. The most obvious additions are a small speaker and MEMS microphone allowing kids to interact with audio in their code, but less obvious is a new touch button in the micro:bit logo. The original had it in the silk screen layer, while the new one has it as copper for a capacitive sensor.
The silicon has an upgrade too, now sporting a Nordic Semiconductor nRF52833 running at 64 MHz and sporting 512k of ROM and 128k of RAM with built-in Bluetooth Low Energy. Binaries are incompatible with the original, however all the development environments can recompile code for a new universal binary format capable of running the appropriate software for either version.
The micro:bit has been more of a hit in schools than it has in our community, perhaps because it has the misfortune to have arrived alongside so many strong competitors. However it remains a powerful contender whose easy programming alongside the power of more traditional toolchains make it a good choice for kids and grown-ups alike. We took a look at the original back in 2016, if you are interested.
We’re not sure what to call this one. Is it a circuit sculpture? Sort of, but it moves, so perhaps it’s a kinetic circuit sculpture. Creator [Tomohiro Tsuchita] calls it “something beautiful but totally useless,” which we find a tad harsh. But whatever you call it, we think this mechanical seven-segment display is really, really cool.
Before anyone gets to thinking that this is something like the other mechanical seven-segment displays we’ve seen lately, think again. This one is not addressable; it simply goes through the ten digits in order. So you won’t be building a clock from it, although we suppose the mechanism could be modified to allow that. Then again, looking at that drive train of laser-cut acrylic cams, maybe not. Each segment has its own cam with lobes or valleys for each segment. A cam follower lowers and raises the segments as the cams rotate on a common shaft. A full-rotation servo powers the display under the control of a Micro:bit; the microcontroller is overkill for now but will be used in version two, which will allow the speed to change in response to sensors.
The Micro:bit is a very neat piece of hardware that, frankly, we don’t see enough of. Which made us all the more interested when [Manoj Nathwani] wrote in to tell us about the gorgeous 3D printed RGB LED lamp he created that uses the BBC-endorsed microcontroller to perform basic gesture detection. Purists will likely point out that an Arduino Pro Mini is tagging along to handle interfacing with the LEDs, but it’s still a good example of how quick you can get a project up and running with MicroPython on the Micro:bit.
[Manoj] used eight NeoPixel Sticks, a NeoPixel Ring, and a few scraps of perfboard to construct a three dimensional “bulb” to fill the void inside the printed diffuser. They’re chained together so all the elements appear as a single addressable strip, which made the rest of the project a bit easier to implement. It might not be pretty, but it gets the job done and it’s not like you’ll ever see it again once installed in the lamp anyway.
The Micro:bit and Arduino co-pilot live in the base of the lamp, and the single USB cable to provide power (and the ability to update the device’s firmware) is run out the bottom to give the whole thing a clean and professional look. For those wondering why the Arduino has tagged along, [Manoj] says he couldn’t get the NeoPixel libraries to play nicely with the Micro:bit so he’s using the Arduino essentially as a mediator.
Right now the only gesture that’s detected on the Micro:bit is a simple shake, which tells the Arduino to toggle the light show on and off. But in the future, [Manoj] plans to implement more complex gestures which will trigger different animations. As he explains in the blog post, gesture recognition with the Micro:bit is incredibly simple, so it should be easy to come up with a bunch of unique ways to interface with the lamp.
As [Paul Bardini] explains on the Thingiverse page for his “Micro:Bit Hand Controller”, the Bluetooth radio baked into the BBC’s educational microcontroller makes it an ideal choice for remotely controlling things. You just need to give it a nice enclosure, a joystick, a couple of buttons, and away you go. You can even use the integrated accelerometer as another axis of control. This is starting to sound a bit familiar, especially to gamers.
While it might not come with the Official Nintendo Seal of Quality, the 3D printable enclosure [Paul] has come up with for the Micro:Bit certainly takes more than a little inspiration from the iconic Wii “Nunchuck” controller. He’s jostled around the positions of the joystick and momentary buttons a bit, but it still has that iconic one-handed ergonomic styling.
In a particularly nice touch, [Paul] has built his controller around a Micro:Bit breakout board from SparkFun that allows you to plug the microcontroller in via its edge connector. This means you can pull the board out and still use it in other projects. The only other connection to the controller leads to the battery, which uses a two pin JST-PH plug that can easily be removed.
Thanks to this breakout board, the internal wiring is exceptionally simple. The joystick (the type used in a PS2 controller) and the buttons are simply soldered directly to pins on the breakout board. No passives required, just a few short lengths of flexible wiring to snake through the printed enclosure.
If you have a Raspberry Pi and have any interest in its peripherals, you may be familiar with the grinning pirate logo of the British company, Pimoroni. The Sheffield, UK based outfit first established a niche for itself as one of the go-to places for much of the essentials of Pi ownership, and has extended its portfolio beyond the Pi into parts, boards, and components across the spectrum of electronic experimentation. Their products are notable for their distinctive and colourful design language as well as their constant exploration of new ideas, and they have rapidly become one of those companies to watch in our sphere. On our way up to Newcastle for Maker Faire UK, we passed close enough to the Pimoroni HQ to be able to ask nicely if we could drop in and have a tour.
The Pimoroni HQ can be found in a nondescript unit with a discreetly placed sign on an industrial estate after a short drive through the city from the motorway. Inside it’s the same as thousands of other units, a set of offices at the front and a cavernous warehouse behind, except this one is filled with the kinds of goodies that get our blood pumping! And we’re told this toybox warehouse is soon to be joined by another nearby unit, as the Pimoroni business is expanding.
Our guide was the company co-founder Paul Beech, whose work you will be familiar with even if this is the first time you’ve heard his name; Paul was the designer of the Raspberry Pi logo! The company is not exclusive to that platform but it’s fair to say they have a strong connection with the Pi, starting in 2012 with as their website puts it: “One laser cutter and a kettle” on which they produced the first of their iconic PiBow laser-cut sandwich Raspberry Pi cases.