Putting the last piece of a project together and finally finishing it up is a satisfying feeling. When the last piece of a puzzle like that is a literal puzzle, though, it’s even better. [Nadieh] has been working on this jigsaw puzzle that displays a fireworks-like effect whenever a piece is placed correctly, using a lot of familiar electronics and some unique, well-polished design.
The puzzle is a hexagonal shape and based on a hexagonally symmetric spirograph, with the puzzle board placed into an enclosure which houses all of the electronics. Each puzzle piece has a piece of copper embedded in a unique location so when it is placed on the board, the device can tell if it was placed properly or not. If it was, an array of color LEDs mounted beneath a translucent diffuser creates a lighting effect that branches across the entire board like an explosion. The large number of pieces requires a multiplexer for the microcontroller, an ATtiny3216.
This project came out of a FabAcademy, so the documentation is incredibly thorough. In fact, everything on this project is open sourced and available on the project page from the code to the files required for cutting out the puzzle pieces and the enclosure. It’s an impressive build with a polish we would expect from a commercial product, and reminds us of an electrified jigsaw puzzle we saw in a previous build.
Before the World Wide Web became ubiquitous as the de facto way to access electronic information, there were many other ways of retrieving information online. One of the most successful of these was Minitel, a French videotex service that lasted from 1980 all the way until 2012. But just because the service has been deactivated doesn’t mean its hardware can’t be used for modern builds like this Arduino-based operating system. (Google Translate from French)
Called ZARDOS, the operating system is built to run on an Arduino MEGA although a smaller version is available for the Uno. The Arduino is connected by a serial cable to the Minitel terminal. It can take input from a keyboard and PS/2 mouse and displays video on the terminal screen with the same cable. There is functionality built-in for accessing data on a cartridge system based on SD cards which greatly expands the limited capabilities of the Atmel chip as well, and there is also support for a speaker and a Videotex printer.
Even though the build uses a modern microcontroller, it gives us flashbacks to pre-WWW days with its retro terminal. All of the code is available on the project site for anyone looking to build an Arduino-based operating system, although it will take a little bit of hardware hacking to build a Minitel terminal like this. Either way, it’s a great way to revive some antique French hardware similar to a build we’ve seen which converts one into a Linux terminal.
One of the hardest, but sometimes best, things you can do for a project is to walk away. [Jroobi] had spent hundreds of hours crafting the digital dash for his MX5 Miata (video, embedded below) and after spending far too long chasing down I2C bugs, he made the difficult decision to step away for a while. However, as of May 2021, [Jroobi] returned to the project and found a power supply was under-specified and was causing brownouts that resulted in crashes.
All in all, it’s an incredible work of engineering. Everything from the massive codebase that describes all the different states to the tasteful graphic design is masterfully done. The Star-Trek-inspired theme and attention to detail really show in the different modes on the tachometer. The dynamic soft RPM limit based on engine temperature is particularly ingenious.
Under the hood of this custom dash are two Ardunios running the show. The center media console offers more controls with a generous touch screen while the instrument cluster shows most of the data. They talk over I2C to each other and communicate with other parts in the car, such as the RGB cabin lighting and the TEIN electronic suspension dampeners. Fuel and temperature levels come in as voltage levels which can be read via an ADC. The gear position is calculated based on RPMs and speed given the wheel size and the transmission in the vehicle.
[Emiel] aka [The Practical Engineer] makes all kinds of fun projects in his fully-featured shop, and one of his tangents has been building a series of solenoid engines. These engines mimic the function of an internal combustion engine, with each solenoid acting as a piston. The only problem with [Emiel]’s concept engines, though, was that he never actually put them into a vehicle to prove their effectiveness. This build finally proves that they can work at powering a vehicle.
The project starts with a new engine. [Emiel] chose a V4 design using four solenoids and an Arduino-based controller. After some trouble getting it to operate properly, he scavenged a small circuit board he built in his V8 solenoid engine to help with timing. With that installed, the solenoids click away and spin the crankshaft at a single constant speed. The vehicle itself was mostly 3D printed, with two aluminum tubes as support structures to mount the engine. Even the wheels were 3D printed with a special rubber coating applied to them. With a small drive train assembled, it’s off to the races for this tiny prototype.
While the small car doesn’t have steering and only goes at a constant speed, the proof of concept that these tiny electric engines actually work is a welcomed addition to [Emiel]’s collection of videos on these curious engines. Of course they’re not as efficient as driving the wheels directly with an electric motor, but we all know there’s no fun in that. If you haven’t seen his most intricate build, the V8 is certainly worth checking out, and also shows off the timing circuitry he repurposed for this car.
Believe it or not, the Mickey Mouse clip used for this demonstration is actually in the public domain.
The earliest televisions used a spinning disk technology called the Nipkow disk, which is exactly what [Science ‘n’ Stuff] recreated with their Arduino-based mechanical color television (video link, also embedded below.) The device reads video and audio from an SD card, and displays the video using a precisely-timed RGB LED visible through a perforated spinning disk. The persistence of vision effect results in a video that is small, relative to the size of the disk, but perfectly watchable. A twist is that the video is in color!
A Nipkow disk is a fairly simple and electromechanical device that relies on timing; something a modern microcontroller and RGB LED is perfectly capable of delivering. In this device, the holes in the disk create 32 vertical scanlines with 96 “pixels” making up each of those lines. Spinning disk technology was always limited to being monochromatic, but in this implementation, each “pixel” is given its own unique color by adjusting the RGB LED accordingly.
The first video shows off the device and demonstrates it working; note that it may look like there are multiple little screens, but the center one can be thought of as the “true” display with the others essentially being artifacts due to light leakage. If you’re interested in the nuts and bolts of exactly how a Nipkow disk works, then the second video is what you’ll be more interested in, because it goes through all the details of exactly how everything functions.
After eight years and much feedback from various readers, I’m proud to offer the second edition of my first book “Arduino Workshop”, from No Starch Press. This is a revised update to this very popular book which is aimed at any person who wants to make electronic devices using the Arduino platform – but has no experience in electronics, programming or microcontrollers.
The reader doesn’t need to buy or read any other book first to get started, from the beginning they are introduced to the basic concepts, required software installation and then introduced to various topics from blinking an LED to controlling devices remotely via a cellular phone.
Contents include:
Chapter 1: Getting Started Chapter 2: Exploring the Arduino Board and the IDE Chapter 3: First Steps Chapter 4: Building Blocks Chapter 5: Working with Functions Chapter 6: Numbers, Variables, and Arithmetic Chapter 7: Expanding Your Arduino Chapter 8: LED Numeric Displays and Matrices Chapter 9: Liquid Crystal Displays Chapter 10: Creating your own Arduino Libraries Chapter 11: Numeric Keypads Chapter 12: Accepting User Input with Touchscreens Chapter 13: Meet the Arduino Family Chapter 14: Motors and Movement Chapter 15: Using GPS with Your Arduino Chapter 16: Wireless Data Chapter 17: Infrared Remote Control Chapter 18: Reading RFID Tags Chapter 19: Data Buses Chapter 20: Real-time Clocks Chapter 21: The Internet Chapter 22: Cellular Communications
You can also review the entire book index from here.
Once the reader has progressed through “Arduino Workshop”, I have found that many people use it as a reference guide for various topics, and saves them time and effort. Instead of searching randomly for various videos, web pages or whatnot – this book offers solid, tried-and-tested information that can be relied on without worry.
Readers of the first edition will also be introduced to new chapters in this edition, such as learning how to create your own Arduino libraries, introduction to the new v2.0 IDE, using new types of LED displays, remote control of devices with LoRA wireless shields, an updated cellular chapter that uses contemporary 3G wireless, and more.
The book is printed using a convenient lie-flat technology, so you can have the book open to your side and not worry about the pages flapping about and losing your position while working on your projects. All the required code (or Arduino “sketches”) are included in the book, however you can also download them along with a list of parts and supplier information from the book’s website.
The Arduino platform in my opinion is still the easiest and most approachable way of learning about electronics and microcontrollers, and opens up a whole new world of creativity or even the pathway to a career in technology, and a copy of “Arduino Workshop” is the best guide to this world.
You can learn more about the book and order from the No Starch Press online store, amazon, kindle, or your preferred bookseller. Orders from No Starch Press also include a free electronic copy so you can get started immediately.
Smart watches are pretty common today, but how many people do you know with a smart hat? [Oliver] built Wilson which he bills as “the IoT hat.” We wonder if the name was inspired by the Home Improvement character of the same name who only appeared as a hat above the fence line. You can see a video of the project, below.
The project is pretty straightforward for hardware. An LED strip, an Arduino, and a Bluetooth module. Oh. And a hat. The software, as you might expect, is a bit more complex. It allows you to display SMS messages to your hat.
As wearables go, your happiness with this project will depend on what’s important to you. If you want to read your text messages, you might like to stick with a watch since it is hard to see a hat while it is on your head. But if you want to show the world what’s on your mind — and your phone — this might be just the ticket.
Regardless of practicality, we thought it was a fun project and now that in person meetups are coming back, a great thing to wear at the next Supercon. It sure looks nicer than the heads up baseball cap, although you can read that one yourself. Oddly enough, most of the hat hacks we see involve baseball caps.
Ok, we’ll come clean. [Design Build Destroy] didn’t really add any memory to his Arduino Nano. But he did get about 1.5K more program space when compared to the stock setup. The trick? On some Nano boards and clones, the bootloader is set to use a large block of reserved memory, but Optiboot only requires a fraction of that reserved memory. By reprogramming the bootloader and changing the configuration fuses, you can reclaim that unused memory.
Of course, you can’t easily overwrite the bootloader and fuses over the serial port to prevent you from bricking your device. The video below shows how to connect another Arduino to do the programming. You could also use any dedicated AVR programmer you happen to have. Oddly, the Uno already uses Optiboot with the same processors, and is set correctly and the video shows the differences in the configuration between the two in their default state.
Of course, depending on where you get your Nano devices and their age, you may already have this set up at which point you won’t gain anything, but you should be able to easily tell if you need to go through the steps or not. The same trick will probably work with any older Arduino boards you have laying around if Optiboot supports them. What can you do with the extra memory? Maybe speech recognition?
Let’s face it — eating different colored candy like M&Ms or Skittles is just a little more fun if you sort your pile by color first. The not-fun part is having to do it by hand. [Jackofalltrades_] decided to tackle this time-worn problem for engineering class because it’s awesome and it satisfies the project’s requirement for sensing, actuation, and autonomous sequencing. We’d venture to guess that it satisfies [Jackofalltrades_]’ need for chocolate, too.
Here’s how it works: one by one, M&Ms are selected, pulled into a dark chamber for color inspection, and then dispensed into the proper cubby based on the result. [Jackofalltrades_] lived up to their handle and built a color-detecting setup out of an RGB LED and light-dependent resistor. The RGB LED shines red, then, green, then blue at full brightness, and takes a voltage reading from the photocell to figure out the candy’s color. At the beginning, the machine needs one of each color to read in and store as references. Then it can sort the whole bag, comparing each M&M to the reference values and updating them with each new M&M to create a sort of rolling average.
We love the beautiful and compact design of this machine, which was built to maximize the 3D printer as one of the few available tools. The mechanical design is particularly elegant. It cleverly uses stepper-driven rotation and only needs one part to do most of the entire process of isolating each one, passing it into the darkness chamber for color inspection, and then dispensing it into the right section of the jar below. Be sure to check out the demo after the break.
Need a next-level sorter? Here’s one that locates and separates the holy grail of candy-coated chocolate — peanut M&Ms that didn’t get a peanut.
It’s fair to say that the Nintendo 64 and GameCube both had the most unique controllers of their respective console generations. The latter’s gamepads are still in high demand today as the Smash Bros. community continues to favor its traditional control scheme. However, both controllers can easily be repurposed for musical means, thanks to work by [po8aster].
The project comes in two forms – the GC MIDI Controller and the N64 MIDI Controller, respectively. Each uses an Arduino Pro Micro to run the show, a logic level converter, and [NicoHood’s] Nintendo library to communicate with the controllers. From there, controller inputs are mapped to MIDI signals, and pumped out over traditional or USB MIDI.
Both versions come complete with a synth mode and drum mode, in order to allow the user to effectively play melodies or percussion. There’s also a special mapping for playing drums using the Donkey Konga Bongo controller with the GameCube version. For those eager to buy a working unit rather than building their own, they’re available for purchase on [po8aster’s] website.
It’s a fun repurposing of video game hardware to musical ends, and we’re sure there’s a few chiptune bands out there that would love to perform with such a setup. We’ve seen other great MIDI hacks on Nintendo hardware before, from the circuit-bent SNES visualizer to the MIDI synthesizer Game Boy Advance. Video after the break.
If you wanna be a cool nerd who uses video game controllers to play music, I’m doing a birthday sale, 20% off all the things!