A 4-Player Arcade Hidden Inside A Coffee Table

May 11, 2023 by 3 Comments

[Ed] from 50% Awesome on YouTube wanted to build a retro gaming system with a decent screen size, but doesn’t have a great deal of space to site it in, so a good compromise was to make a piece of useful furniture and hide all the fun parts inside.

Building an arcade machine usually involves a lot of wiring

This video two-part build log shows a lot of woodwork, with a lot of mistakes (happy accidents, that are totally fine) made along the way, so you do need to repeat them. Essentially it’s a simple maple-veneered plywood box, with a thick lid section hosting the display and some repositioned speakers. This display is taken from a standard LG TV with the control PCB ripped out. The power button/IR PCB was prised out of the bezel, to be relocated, as were the two downwards-facing speakers. The whole collection of parts was attached to a front panel, with copious hot glue, we just hope the heavy TV panel was firmly held in there by other means!

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The World’s First Agricultural Right To Repair Law

April 29, 2023 by 29 Comments

Long time readers will know that occasionally we mix up our usual subject matter with a dash of farm equipment. Usually the yellow and green variants that come from John Deere, as the agricultural manufacturer has become the poster child for all that is wrong in the fight for the right to repair. An old Deere is worth more than a nearly new one in many places, because for several years now their models have had all their parts locked down by DRM technologies such that only their own fitters can replace them. Now after a long legal fight involving many parties, the repair and parts company iFixit sound justifiably pleased as they announce the world’s first agricultural right to repair law being passed in the US state of Colorado. (Nitter)

This may sound like a small victory, and it will no doubt be followed by further rearguard actions from the industry as similar laws are tabled in other states. But in fact as we read it, with this law in place the game is de facto up for the tractor makers. Once they are required to release any access codes for the Coloradans those same codes will by extension be available to any other farmers, and though we’re guessing they won’t do this, they would be best advised to give up on the whole DRM idea and concentrate instead on making better tractors to fix their by-now-damaged brands.

It’s exciting news for everybody as it proves that right-to-repair legislation is possible, however since this applies only to agricultural machinery the battle is by no means over. Only when all machines and devices have the same protection can we truly be said to have achieved the right to repair.

We’ve reported on this story for a long time, here’s a previous piece of legislation tried in another state.

Air Hockey Solitaire

April 22, 2023 by 3 Comments

While air hockey is a fine amusement, it isn’t much fun if you can’t find someone to play against. Unless that is, you build a mini table with a robotic defender. [Vaib], [Nathan], and [Navish] can show you how. There is a video you can see below that shows two players using the table without the robot.

The project takes a bit of woodworking, as you might expect. You also have to drill 576 holes for the air to lift the puck. Some of the components are 3D printed in PETG, too. The automated defense uses a camera and relies on the fact that the puck is the only red thing on the table. A servo moves to intercept the incoming puck and return the shot. We were disappointed the video didn’t show the automated play.

We wondered if they had considered making a pair of the detachable robots and letting them play with each other. If you prefer football, the robot could probably adapt. We’ve seen other robot air hockey contenders, so maybe a better idea would be to build different robots and let them compete for a gold medal.

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3D-Printable Foaming Nozzle Shows How They Work

April 16, 2023 by 8 Comments

[Jack]’s design for a 3D-printable foaming nozzle works by mixing air with a fluid like liquid soap or hand sanitizer. This mixture gets forced through what looks like layers of fine-mesh sieve and eventually out the end by squeezing the bottle. The nozzle has no moving parts but does have an interesting structure to make this possible.

The fine meshes are formed by multiple layers of bridged filament.

Creating a foam with liquid soap requires roughly one part soap to nine parts air. The idea is that the resulting foam makes more efficient use of the liquid soap compared to dispensing an un-lathered goop directly onto one’s hands.

The really neat part is that the fine mesh structure inside the nozzle is created by having the printer stretch multiple layers of filament across the open span on the inside of the model. This is a technique similar to that used for creating bristles on 3D-printed brushes.

While this sort of thing may require a bit of expert tweaking to get the best results, it really showcases the way the fundamentals of how filament printers work. Once one knows the process, it can be exploited to get results that would be impossible elsewhere. Here are a few more examples of that: printing only a wall’s infill to allow airflow, manipulating “vase mode” to create volumes with structural ribs, and embedding a fine fabric mesh (like tulle) as either a fan filter or wearable and flexible armor. Everything’s got edge cases, and clever people can do some pretty neat things with them (when access isn’t restricted, that is.)

PCIe For Hackers: The Diffpair Prelude

March 14, 2023 by 35 Comments

PCIe, also known as PCI-Express, is a highly powerful interface. So let’s see what it takes to hack on something that powerful. PCIe is be a bit intimidating at first, however it is reasonably simple to start building PCIe stuff, and the interface is quite resilient for hobbyist-level technology. There will come a time when we want to use a PCIe chip in our designs, or perhaps, make use of the PCIe connection available on a certain Compute Module, and it’s good to make sure that we’re ready for that.

PCIe is everywhere now. Every modern computer has a bunch of PCIe devices performing crucial functions, and even iPhones use PCIe internally to connect the CPU with the flash and WiFi chips. You can get all kinds of PCIe devices: Ethernet controllers, high-throughput WiFi cards, graphics, and all the cheap NVMe drives that gladly provide you with heaps of storage when connected over PCIe. If you’re hacking on a laptop or a single-board computer and you’d like to add a PCIe device, you can get some PCIe from one of the PCIe-carrying sockets, or just tap into an existing PCIe link if there’s no socket to connect to. It’s been two decades since we’ve started getting PCIe devices – now, PCIe is on its 5.0 revision, and it’s clear that it’s here to stay.

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Enzymes Make Electricity From Thin Air

March 11, 2023 by 17 Comments

There’s an old magic trick known as the miser’s dream, where the magician appears to pull coins from thin air. Australian scientists say they can now generate electricity out of thin air with the help of some enzymes. The enzyme reacts to hydrogen in the atmosphere to generate a current.

They learned the trick from bacteria which are known to use hydrogen for fuel in inhospitable environments like Antarctica or in volcanic craters. Scientists knew hydrogen was involved but didn’t know how it worked until now.

The enzyme is very efficient and can even work on trace amounts of hydrogen. The enzyme can survive freezing and temperature up to 80 °C (176 °F). The paper seems more intent on the physical mechanisms involved, but you can tell the current generated is minuscule. We don’t expect to see air-powered cell phones anytime soon. Then again, you have to start somewhere, and who knows where this could lead?

Microbial fuel cells aren’t new, of course. If you just want lights, you can skip the electricity altogether.

The First Gui? Volscan Controls The Air

March 9, 2023 by 10 Comments

In the 1950s,  computers were, for the most part, ponderous machines. But one machine offered a glimpse of the future. The Volscan was probably the first real air traffic computer designed to handle high volumes of military aircraft operations. It used a light gun that looked more like a soldering gun than a computer input device. There isn’t much data about Volscan, but it appears to have been before its time, and had arguably the first GUI on a computer system ever.

The Air Force had a problem. The new — in the 1950s — jets needed long landing approaches and timely landings since they burned more fuel at lower altitudes. According to the Air Force, they could land 40 planes in an hour, but they needed to be able to do 120 planes an hour. The Whirlwind computer had proven that computers could process radar data — although Whirlwind was getting the data over phone lines from a distance. So the Air Force’s Cambridge Research Center started working on a computerized system to land planes called Volscan, later known as AN/GSN-3.

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