Almost Breaking The World Record For The Tiniest Humanoid Robot, But Not Quite

May 23, 2024 by 14 Comments

Did you know there is a Guinness World Record for the smallest humanoid robot? We didn’t either, but apparently this is a challenge attracting multiple competitors. [Lidor Shimoni] had a red hot go at claiming the record, but came up ever so slightly short. Or tall.

The former record holder was measured at 141 mm, so [Lidor] had to beat that. He set about building a humanoid robot 95 mm tall, relying on off-the-shelf parts and 3D-printed components of his own design. An ESP32 served as the brains of the operation, while the robot, named Tiny Titan, got big flat feet to make walking relatively stable and controlled. Small servos were stacked up to actuate the legs and create a suitably humanoid robot to claim the title.

Sadly, [Lidor] was pipped to the post. Some procrastinating in finishing the robot and documentation saw another rival with a 60mm robot take the record. It’s not 100% clear what Guinness requires for someone to take this record, but it seems to involve a robot with arms, legs, and some ability to walk.

Sometimes robots are more fun when they’re very small. If you’re developing your own record-breaking automatons, drop us a line won’t you?

Turning An ATX PSU Into A Variable Bench Supply

May 23, 2024 by 90 Comments

Bench power supplies can sometimes be frustratingly expensive and also kind of limited. If you’re enterprising and creative, though, you can create your own bench supply with tons of features, and it doesn’t have to break the bank either. Do what [Maker Y] did—grab an ATX supply and get building!

ATX power supplies work as a great basis for a bench power supply. They have 12 volt, 3.3 volt, and 5 volt rails, and they can supply a ton of current for whatever you might need. [Maker Y] decided to break out these rails on banana plugs for ease of access, and fused them for safety, too. But the build doesn’t stop there. [Maker Y] also added a buck-boost converter to provide a variable voltage output from 1 to 30 volts for added flexibility. As a nice final touch, the rig also features a pair of USB A ports compatible with Quick Charge 3.0, for keeping smart devices charged while working in the lab.

[Caelestis Workshop] also designed a fully enclosed version if you prefer that style. Check it out on Instructables.

No matter which way you go, it’s a pretty simple build, with a bunch of off-the-shelf parts tossed together in a 3D printed housing. Ultimately, though, it’s got more functionality than a lot of cheap off-the-shelf bench supplies. You can build it just about anywhere on Earth where you can get cheap eBay parts via post. Continue reading “Turning An ATX PSU Into A Variable Bench Supply” →

Mapping The Human Brain And Where This May Lead Us

May 23, 2024 by 31 Comments

In order to understand something, it helps to observe it up close and study its inner workings. This is no less true for the brain, whether it is the brain of a mouse, that of a whale, or the squishy brain inside our own skulls. It defines after all us as a person; containing our personality and all our desires and dreams. There are also many injuries, disorders and illnesses that affect the brain, many of which we understand as poorly as the basics of how memories are stored and thoughts are formed. Much of this is due to how complicated the brain is to study in a controlled fashion.

Recently a breakthrough was made in the form of a detailed map of the cells and synapses in a segment of a human brain sample. This collaboration between Harvard and Google resulted in the most detailed look at human brain tissue so far, contained in a mere 1.4 petabytes of data. Far from a full brain map, this particular effort involved only a cubic millimeter of the human temporal cortex, containing 57,000 cells, 230 millimeters of blood vessels and 150 million synapses.

Ultimately the goal is to create a full map of a human brain like this, with each synapse and other structures detailed. If we can pull it off, the implications could be mind-bending.

Continue reading “Mapping The Human Brain And Where This May Lead Us” →

Grid Leak Radio Draws The Waves

May 23, 2024 by 11 Comments

[Stephen McNamera] found a schematic for a grid leak radio online and decided to throw together a few tubes on a piece of wood and see how it worked. As you can see in the video below, it works well. The video is a bit light on details, but the web page he found the plans on also has quite a bit of explanation.

The name “grid leak detector” is due to the grid leak resistor between the grid and ground, in this case, a 2.7 megaohm resistor. The first tube does everything, including AM detection. The second tube is just an audio amplifier that drives the speaker. This demodulation method relies on the cathode to control grid conduction characteristics and was found in radios up to about the 1930s. The control grid performs the usual function but also acts as a diode with the cathode, providing demodulation. In a way, this is similar to a crystal radio but with an amplified tube diode instead of a crystal.

It looks like [Stephen] wound his own coil, and the variable capacitor looks suspiciously like it may have come from an old AM radio. The of the old screw terminal tube sockets on the wood board looks great. Breadboard indeed! What we didn’t see is where the 150 V plate voltage comes from. You hope there is a transformer somewhere and some filter capacitors. Or, perhaps he has a high-voltage supply on the bench.

While tubes are technologically passe, we still like them. Especially in old radios. Just take care around the high voltages, please.

Continue reading “Grid Leak Radio Draws The Waves” →

Design Review: USB-C PD Input For Yaesu FRG7700

May 23, 2024 by 21 Comments

Today is another board from a friend, [treble], who wants to convert a Yaesu FRG7700 radio to USB-C PD power. It’s yet another review that I’ve done privately, and then realized I’ve made more than enough changes to it, to the point that others could learn from this review quite a bit. With our hacker’s consent, I’m now sharing these things with you all, so that we can improve our boards further and further.

This board’s idea is thought-out and executed well – it replaces a bespoke barrel jack assembly, and is mechanically designed to fit the screw holes and the free space inside the chassis. For USB-PD, it uses a CH32V003 coupled with FUSB302 – I definitely did help pick the latter! For mechanical reasons, this board is split into two parts – one has the USB-C port, whereas the other has the MCU and the PD PHY.

In short, this board is a PD trigger. Unlike the usual PD triggers, however, this one is fully configurable, since it has a 32-bit MCU with good software support, plus, the PD PHY is also well known and easily controllable. So, if you want special behavior like charger-power-dependent profile selection for powering a static resistance load, you can implement it easily – or, say, you can do PPS for variable voltage or even lithium ion battery charging! With a bit of extra code, you could even do EPR (28 V = 140 W power) with this board, instantly making it into a pretty advanced PD trigger, beyond the ones available on the market.

Also, the board has some PCB art, and a very handy filter to get some of the USB-C charger noise out. Let’s take a look at all of these!

Current Flow Improvements

Continue reading “Design Review: USB-C PD Input For Yaesu FRG7700” →

CADmium Moves CAD To The Browser

May 23, 2024 by 43 Comments

For plenty of computer users, the operating system of choice is largely a middleman on the way to the browser, which hosts the tools that are most important. There are even entire operating systems with little more than browser support, under the assumption that everything will be done in the browser eventually. We may be one step closer to that type of utopia as well with this software tool called CADmium which runs exclusively in a browser.

As the name implies, this is a computer-aided design (CAD) package which looks to build everything one would need for designing project models in a traditional CAD program like AutoCAD or FreeCAD, but without the burden of needing to carry local files around on a specific computer. [Matt], one of the creators of this ambitious project, lays out the basic structure of a CAD program from the constraint solver, boundary representation (in this case, a modern one built in Rust), the history tracker, and various other underpinnings of a program like this. The group hopes to standardize around JSON files as well, making it easy to make changes to designs on the fly in whatever browser the user happens to have on hand.

While this project is extremely early in the design stage, it looks like they have a fairly solid framework going to get this developed. That said, they are looking for some more help getting it off the ground. If you’ve ever wanted something like this in the browser, or maybe if you’ve ever contributed to the FreeCAD project and have some experience, this might be worth taking a look at.

An image of a grey plastic carrying case, approximately the size of an A5 notebook. Inside are darker grey felt lined cubbies with a mirror, piece of glass, a viewfinder, and various small printed parts to assemble a camera lucida.

Camera Lucida – Drawing Better Like It’s 1807

May 23, 2024 by 15 Comments

As the debate rages on about the value of AI-generated art, [Chris Borge] printed his own version of another technology that’s been the subject of debate about what constitutes real art. Meet the camera lucida.

Developed in the early part of the nineteenth century by [William Hyde Wollaston], the camera lucida is a seemingly simple device. Using a prism or a mirror and piece of glass, it allows a person to see the world overlaid onto their drawing surface. This moves details like proportions and shading directly to the paper instead of requiring an intermediary step in the artist’s memory. Of course, nothing is a substitute for practice and skill. [Professor Pablo Garcia] relates a story in the video about how [Henry Fox Talbot] was unsatisfied with his drawings made using the device, and how this experience was instrumental in his later photographic experiments.

[Borge]’s own contribution to the camera lucida is a portable version that you can print yourself and assemble for about $20. Featuring a snazzy case that holds all the components nice and snug on laser cut felt, he wanted a version that could go in the field and not require a table. The case also acts as a stand for the camera to sit at an appropriate height so he can sketch landscapes in his lap while out and about.

Interested in more drawing-related hacks? How about this sand drawing bot or some Truly Terrible Dimensioned Drawings?

Continue reading “Camera Lucida – Drawing Better Like It’s 1807” →