tiny

24 Articles

The Design Process For A Tiny Robot Brain

October 20, 2024 by 13 Comments

As things get smaller, we can fit more processing power into devices like robots to allow them to do more things or interact with their environment in new ways. If not, we can at least build them for less cost. But the design process can get exponentially more complicated when miniaturizing things. [Carl] wanted to build the smallest 9-axis robotic microcontroller with as many features as possible, and went through a number of design iterations to finally get to this extremely small robotics platform.

Although there are smaller wireless-enabled microcontrollers, [Carl] based this project around the popular ESP32 platform to allow it to be usable by a wider range of people. With that module taking up most of the top side of the PCB, he turned to the bottom to add the rest of the components for the platform. The first thing to add was a power management circuit, and after one iteration he settled on a circuit which can provide the board power from a battery or a USB cable, while also managing the battery’s charge. As for sensors, it has a light sensor and an optional 9-axis motion sensor, allowing for gesture sensing, proximity detection, and motion tracking.

Of course there were some compromises in this design to minimize the footprint, like placing the antenna near the USB-C charger and sacrificing some processing power compared to other development boards like the STM-32. But for the size and cost of components it’s hard to get so many features in such a small package. [Carl] is using it to build some pretty tiny robots so it suits his needs perfectly. In fact, it’s hard to find anything smaller that isn’t a bristlebot.

Continue reading “The Design Process For A Tiny Robot Brain” →

Forget Ship In A Bottle, How About Joule Thief In A Fuse Tube?

August 7, 2024 by 14 Comments

We love close-up pictures of intricate work, and [w] hits the spot with a tiny joule thief in a fuse case (social media post, embedded below) powered by an old coin cell from a watch. It’s so tiny!

Ethernet transformers contain tiny coils.

A joule thief is a sort of minimum-component voltage booster that can suck nearly every last drop of energy from even seemingly-drained batteries, and is probably most famously used to light LEDs from cells that are considered “dead”.

Many joule thief designs feature hand-wound coils, which is great for junk box builds but certainly becomes more of a challenge for a tiny build like this one.

We really like that [w] salvaged a miniscule coil from an Ethernet transformer, most of which look like blocky SMD components from the outside but actually contain tiny coils.

The joule thief has been the basis of plenty of hacks over the years, and it’s always nice to see new twists on the concept.

Continue reading “Forget Ship In A Bottle, How About Joule Thief In A Fuse Tube?” →

CW Not Hard Enough? Try This Tiny Paddle

July 22, 2024 by 7 Comments

For a long time, a Morse code proficiency was required to obtain an amateur radio license in many jurisdictions around the world, which was a much higher bar of entry than most new hams have to pass. Morse, or continuous wave (CW) is a difficult skill to master, and since the requirement has been dropped from most licensing requirements few radio operators pick up this skill anymore. But if you like a challenge, and Morse itself isn’t hard enough for you, you might want to try out this extremely small Morse paddle.

Originally meant for portable operation, where hiking to something like a mountain top with radio gear demands small, lightweight, and low-power options, this paddle is actually not too complex. It attaches to most radios with a 3.5 mm stereo cable and only has two paddles on flexible metal arms which, when pressed against the center of the device, tell the radio to either produce continuous “dits” or “dahs”. For portable use the key sits inside a tiny plastic case and only needs to be pulled out and flipped around to get started. And, while not waterproof, [N6ARA] reports that it’s so small you likely could just shield it from the rain with your other hand if you needed to.

Presumably, this paddle actually wouldn’t be that much different than using any other paddle except for the fact that it’s not heavy enough to resist the force of use, so you’d have to hold it with your other hand anyway. And, while this is a product available for purchase it’s simple enough that, presumably, the design could easily be duplicated with just a few parts. Paddles like this were made as an improvement to older technology like straight keys which require the operator to produce the correct lengths of tones for each character manually. While you can get higher speeds with a paddle, there are still some dedicated CW operators using a straight key.

Continue reading “CW Not Hard Enough? Try This Tiny Paddle” →

How Small Can The ESP32 Get?

September 7, 2023 by 25 Comments

At its core, the ESP32 chip is not much more than an integrated circuit, a huge mass of transistors sealed inside an epoxy resin package with some leads. Of course, most of us won’t buy discrete ESP32 chips with no support circuitry since it’s typically easier and often not that much more expensive to get them paired with development boards of some type for easy access to things like USB and GPIO. But these tiny chips need little in the way of support to get up and running as [Paul] demonstrates with this tiny ESP32 board.

The project started as a challenge for [Paul] to build the smallest ESP32 that would still function. That means carving away nearly everything normally found accompanying one of these chips. There is no charging circuitry, only one of the GPIO pins is accessible, and it even foregoes the WiFi antennas which eliminates the major reason most people would reach for this chip in the first place. But at this form factor even without wireless capabilities it still blows other chips of this stature, like the ATtiny series, out of the water.

Even though [Paul] built it as a challenge, it goes a long way to demonstrate what’s really needed to get one of these chips up and running properly. And plenty of projects don’t need a ton of I/O or Wi-Fi either, so presuming these individual chips can be found cheaply and boards produced for various projects its an excellent way to minimize size and perhaps even power requirements. You can make these boards even smaller than a USB-A connector if you want to take this process even further, too.

Continue reading “How Small Can The ESP32 Get?” →

Tiny Pinball Machine Also Runs X86 Code

July 21, 2022 by 13 Comments

As arcades become more and more rare, plenty of pinball enthusiasts are moving these intricate machines to their home collections in basements, garages, and guest rooms. But if you’re not fortunate enough to live in a home that can support a space-intensive hobby like pinball machines, there are some solutions to that problem. This one, for example, fits on the palm of your hand and also happens to run some impressive software for its size.

The machine isn’t a mechanical pinball machine like its larger cousins, though. Its essentially a 3D printed case made to look like a pinball machine with two screens attached. It does have a working plunger for launching the ball and two buttons on the sides for the approximation of authenticity, but it’s actually running Pinball Fantasies — a pinball simulator designed to run on x86 hardware from the 90s. This sports an ESP32 on the inside, which has just enough computing capability to run an x86 emulator that can load these games in DOS.

The game includes haptic feedback and zips along at 60 frames per second, which really brings the pinball experience to its maximum level given the game’s minuscule size. It’s impressive for fitting a lot into a small space, both from physical and software points-of-view. For more full-sized digital pinball builds, take a look at this one which comes exceptionally close to replicating the real thing.

Continue reading “Tiny Pinball Machine Also Runs X86 Code” →

Bringing An IPod To The Modern NAND Era

August 4, 2020 by 21 Comments

Flash storage was a pretty big deal back in the mid ’00s, although the storage sizes that were available at the time seem laughable by today’s standards. For example, having an iPod that didn’t have a spinning, unreliable hard drive was huge even if the size was measured in single-digit gigabytes, since iPods tended to not be treated with the same amount of care as something like a laptop. Sadly, these small iPods aren’t available anymore, and if you want one with more than 8GB of storage you’ll have to upgrade an old one yourself.

This build comes to us from [Hugo] who made the painstaking effort of removing the old NAND flash storage chip from an iPod Nano by hand, soldering 0.15mm enameled magnet wire to an 0.5mm pitch footprint to attach a breakout board. Once the delicate work was done, he set about trying to figure out the software. In theory the iPod should have a maximum addressable space of 64 GB but trying to get custom firmware on this specific iPod is more of a challenge and the drives don’t simply plug-and-play. He is currently using the rig for testing a new 8GB and new 16GB chip though but it shows promise and hopefully he’ll be able to expand to that maximum drive size soon.

The build is really worth a look if you’re into breathing new life into old media players. Sometimes, though all these old iPods really need to get working again is just to be thrown into a refrigerator, as some genius engineer showed us many years ago.

Tiny LED Cube Packs Six Meters Of Madness

September 8, 2019 by 11 Comments

When [Freddie] was faced with the challenge of building a sendoff gift for an an LED-loving coworker he hatched a plan. Instead of making a display from existing video wall LED panels he would make a cube. But not just any cube, a miniature desk sized one that wasn’t short of features or performance. We’d be over the moon if someone gifted us with this itty-bitty Qi coil-powered masterpiece of an RGB cube.

Recently we’ve been blessed with a bevy of beautiful, animated RGB cubes but none hit quite this intersection of size and function. The key ingredient here is tiny but affordable RGB LEDs which measure 1 mm on a side. But LEDs this small are dwarfed by the otherwise minuscule “2020” package WS2812’s and APA102s of the world. Pushing his layout capabilities to the max [Freddie] squeezed each package together into a grid with elements separated by less than 1 mm, resulting in a 64 LED panel that is only 16 mm x 16 mm panel (with test points and controller mounted to the back). Each of these four-layer PCBs that makes up the completed cube contains an astonishing 950 mm of tracking, meaning the entire cube has nearly six meters of traces!

How do you power such a small device with no obvious places to locate a connector? By running magnet wire through a corner and down to a Qi coil of course. Not to let the cube itself outshine the power supply [Freddie] managed to deadbug a suitably impressive supply on the back of the coil itself. Notice the grain of rice in the photo to the left! The only downside here is that the processor – which hangs diagonally in the cube on a tiny motherboard – cannot be reprogrammed. Hopefully future versions will run programming lines out as well.

Check out the video of the cube in action after the break, and the linked photo album for much higher resolution macro photos of the build. While you’re there take a moment to admire the layout sample from one of the panels! If this sets the tone, we’re hoping to see more of [Freddie]’s going-away hacks in the future!

Continue reading “Tiny LED Cube Packs Six Meters Of Madness” →