Printing An Air-Powered Integrated Circuit For Squishy Robots

October 15, 2025 by 9 Comments

There’s no rule that says that logic circuits must always use electrically conductive materials, which is why you can use water, air or even purely mechanical means to implement logic circuits. When it comes to [soiboi soft]’s squishy robots, it thus makes sense to turn the typical semiconductor control circuitry into an air-powered version as much as possible.

We previously featured the soft and squishy salamander robot that [soiboi] created using pneumatic muscles. While rather agile, it still has to drag a whole umbilical of pneumatic tubes along, with one tube per function. Most of the research is on microfluidics, but fortunately air is just a fluid that’s heavily challenged in the density department, allowing the designs to be adapted to create structures like gates and resistors.

A transistor or valve using a silicone membrane. (Credit: soiboi soft, YouTube)
A transistor or valve using a silicone membrane. (Credit: soiboi soft, YouTube)

Logically, a voltage potential or a pressure differential isn’t so different, and can be used in a similar way. A transistor for example is akin to the vacuum tube, which in British English is called a valve for good reason. Through creative use of a flexible silicone membrane and rigid channels, pulling a vacuum in the ‘gate’ channel allows flow through the other two channels.

Similarly, a ‘resistor’ is simply a narrowing of a channel, thus resisting flow. The main difference compared to the microfluidics versions is everything is a much larger scale. This does make it printable on a standard FDM printer, which is a major benefit.

Quantifying these pneumatic resistors took a bit of work, using a pressure sensor to determine their impact, but after that the first pneumatic logic circuits could be designed. The resistors are useful here as pull-downs, to ensure that any charge (air) is removed, while not impeding activation.

The design, as shown in the top image, is a 5-stage ring oscillator that provides locomotion to a set of five pneumatic muscles. As demonstrated at the end of video, this design allows for the entire walking motion to be powered using a single input of compressed air, not unlike the semiconductor equivalent running off a battery.

While the somewhat bulky nature of pneumatic logic prevents it from implementing very complex logic, using it for implementing something as predictable as a walking pattern as demonstrated seems like an ideal use case. When it comes to making these squishy robots stand-alone, it likely can reduce the overall bulk of the package, not to mention the power usage. We are looking forward to how [soiboi]’s squishy robots develop and integrate these pneumatic circuits.

Continue reading “Printing An Air-Powered Integrated Circuit For Squishy Robots” →

2025 Hackaday Supercon: Crafting The Final Frontier Keynote Event

October 15, 2025 by No comments

In the history of entertainment, few properties have made the sort of indelible mark on popular culture as Star Trek has. In 950 episodes across the twelve television series that have carried the name, the franchise has made a spectacle not of explosions and machismo, but of competent professionals working together to solve complex problems. In the world of Star Trek, the coolest people in the room are the scientists, engineers, physicists, and doctors — is it any wonder so many in the sciences credit the show for putting them on their career path?

Hardware hacker, maker, and Trekkie Andrew [MakeItHackin] will lead the panel.
To celebrate the impact of Star Trek, we’re proud to announce our keynote event for the 2025 Hackaday Supercon: Crafting the Final Frontier. This round-table discussion led by Andrew [MakeItHackin] will bring together some of the artists that have helped cultivate the look and feel of the final frontier since Star Trek: The Next Generation and all the way into the modern era with Star Trek: Picard.

While the art direction of the original Star Trek series from 1966 was remarkably ahead of its time, these are some of the key individuals who were brought in to refine those early rough-hewn ideas into cultural touchstones. Their work ended up becoming more than simple entertainment, and ultimately helped inspire some of the real-world technology we use on a daily basis. The iconic LCARS computer interface predicted the rise of the touch screen, while its impossible to look at props such as the PADD and Tricorder and not see the parallels with modern tablets and smartphones.

Continue reading “2025 Hackaday Supercon: Crafting The Final Frontier Keynote Event” →

Keep That Engine Running, With A Gassifier

October 15, 2025 by 47 Comments

Every now and then in histories of the 20th’s century’s earlier years, you will see pictures of cars and commercial vehicles equipped with bulky drums, contraptions to make their fuel from waste wood. These are portable gas generators known as gasifiers, and to show how they work there’s [Greenhill Forge] with a build video.

A gasifier on a vintage tractor
A gasifier on a vintage tractor. Per Larssons Museum, CC BY 2.5.

When you burn a piece of wood, you expect to see flame. But what you are looking at in that flame are the gaseous products of the wood breaking down under the heat of combustion. The gasifier carefully regulates a burn to avoid that final flame, with the flammable gasses instead being drawn off for use as fuel.

The chemistry is straightforward enough, with exothermic combustion producing heat, water vapour, and carbon dioxide, before a further endothermic reduction stage produces carbon monoxide and hydrogen. He’s running his system from charcoal which is close to pure carbon presumably to avoid dealing with tar, and at this stage he’s not adding any steam, so we’re a little mystified as to where the hydrogen comes from unless there is enough water vapour in the air.

His retort is fabricated from sheets steel, and is followed by a cyclone and a filter drum to remove particulates from the gas. It relies on a forced air draft from a fan or a small internal combustion engine, and we’re surprised both how quickly it ignites and how relatively low a temperature the output gas settles at. The engine runs with a surprisingly simple gas mixer in place of a carburetor, and seems to be quite smooth in operation.

This is one of those devices that has fascinated us for a long time, and we’re grateful for the chance to see it up close. The video is below the break, and we’re promised a series of follow-ups as the design is refined.

Continue reading “Keep That Engine Running, With A Gassifier” →

Rubik’s WOWCube: What Really Makes A Toy?

October 15, 2025 by 17 Comments

If there ever was a toy that enjoys universal appeal and recognition, the humble Rubik’s Cube definitely is on the list. Invented in 1974 by sculptor and professor of architecture Ernő Rubik with originally the name of Magic Cube, it features a three-by-three grid of colored surfaces and an internal mechanism which allows for each of these individual sections of each cube face to be moved to any other face. This makes the goal of returning each face to its original single color into a challenge, one which has both intrigued and vexed many generations over the decades. Maybe you’ve seen one?

Although there have been some variations of the basic 3×3 grid cube design over the years, none have been as controversial as the recently introduced WOWCube. Not only does this feature a measly 2×2 grid on each face, each part of the grid is also a display that is intended to be used alongside an internal processor and motion sensors for digital games. After spending many years in development, the Rubik’s WOWCube recently went up for sale at $299, raising many questions about what market it’s really targeting.

Is the WOWCube a ‘real’ Rubik’s Cube, and what makes something into a memorable toy and what into a mere novelty gadget that is forgotten by the next year like a plague of fidget spinners?

Continue reading “Rubik’s WOWCube: What Really Makes A Toy?” →

The Texas Instruments branding with some schematic symbols in background.

More Than 100 Sub-Circuit Designs From Texas Instruments

October 15, 2025 by 18 Comments

We were recently tipped off to quite a resource — on the Texas Instruments website, there’s a page where you can view and download a compendium of analog sub-circuits.

Individual circuits can be downloaded in the form of PDF files. If you chose to register (which is free), you’ll also gain access to the pair of e-books listed at the bottom of the page: Analog Engineer’s Circuit Cookbook: Amplifiers and Analog Engineer’s Circuit Cookbook: Data Converters. The data converter circuits can be further subdivided into analog-to-digital converter (ADC) circuits and digital-to-analog converter (DAC) circuits.

There are more than 60 amplifier circuits including basic circuits, current sensing circuits, signal sources, current sources, filters, non-linear circuits (rectifiers/clamps/peak detectors), signal conditioning, comparators, sensor acquisition, audio, and integrated amplifier circuits using MSP430 microcontrollers.

You’ll also find 39 analog-to-digital converter (ADC) circuits including low-power, small size, and cost optimized circuits; level translation and input drive circuits; low-level sensor input circuits; input protection, filtering and isolation circuits; and commonly used auxiliary circuits. Finally, there are 15 digital-to-analog converter (DAC) circuits including audio outputs, auxiliary and biasing circuits, current sources, and voltage sources.

Thanks to [Lee Leduc] for letting us know over on the EEVblog Forum.

Factorio Running On Mobile

October 15, 2025 by 26 Comments

As a video game, DOOM has achieved cult status not just for its legendary gameplay and milestone developments but also because it’s the piece of software that’s likely been ported to the most number of platforms. Almost everything with a processor can run the 1993 shooter, but as it ages, this becomes less of a challenge. More modern games are starting to move into this position, and Factorio may be taking a leading position. [Point Substantial] has gotten this game to run on a mobile phone.

The minimum system requirements for Factorio are enough to make this a challenge, especially compared to vintage title like DOOM. For Linux systems a dual-core processor and 8 GB of memory are needed, as well as something with at least 1 GB of VRAM. [Point_Substantial]’s Xiaomi Mi 9T almost meets these official minimum requirements, with the notable exception of RAM. This problem was solved by adding 6 GB of swap space to make up for the difference.

The real key to getting this running is that this phone doesn’t run Android, it runs the Linux-only postmarketOS. Since it’s a full-fledged Linux distribution rather than Android, it can run any software any other Linux computer can, including Steam. And it can also easily handle inputs for periphreals including a Switch Pro controller, which is important because this game doesn’t have touch inputs programmed natively.

The other tool that [Point_Substantial] needed was box86/box64, a translation layer to run x86 code on ARM. But with all the pieces in place it’s quite possible to run plenty of games semi-natively on a system like this. In fact, we’d argue it’s a shame that more phones don’t have support for Linux distributions like postmarketOS based on the latest news about Android.

Thanks to [Keith] for the tip!