RP2040 Gets Intellikeys Keyboard Up And Running

April 29, 2023 by Lewin Day 7 Comments

The Spectronic Intellikeys was an innovative keyboard-like accessibility device that used special plastic overlays that change its functionality. While a USB version of the accessible keyboard exists, it doesn’t work like a normal HID device, so it’s not plug and play as you might expect. It’s also no longer in production or supported by the manufacturer. Where industry falls down, the community steps in, right? To that end, Adafruit has built a tool for interfacing with these useful accessibility devices.

The key is the way the Intellikeys was intended to work with a computer. It was designed to download its firmware from the host machine, using special drivers that are only compatible with certain versions of Windows. That means you can’t use it with iPads or Chromebooks, for example.

To get around this, Adafruit used an RP2040 Feather configured as a USB host to talk to the Intellikeys. It queries the device, determines which overlay it currently has installed, and provides it the necessary firmware. On the other end, the Feather enumerates as a regular USB HID device. That allows it to work with a wide variety of tablets, computers, and even smartphones.

If you’ve got an Intellikeys USB device and miss using it, this could be just the thing you need. Meanwhile, you can check out some of the other interesting keyboard designs we’ve featured over the years.

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Don’t Let The Baluns Float Over Your Head

April 29, 2023 by Bryan Cockfield 5 Comments

Most ham radio operators will build an antenna of some sort when they first start listening or transmitting, whether it’s a simple dipole, a beam antenna like a Yagi, or even just a random wire vertical antenna. All of these will need to be connected feedline of some sort, and in the likely event you reach for some 50-ohm coax cable you’ll also need a balun to reduce noise or unwanted radiation. Don’t be afraid of extra expenses when getting into this hobby, though, as [W6NBC] demonstrates how to construct an “ugly balun” out of the coax wire itself (PDF).

The main purpose of a balun, a contraction of “balanced-unbalanced” is to convert an unbalanced transmission line to a balanced one. However, as [W6NBC] explains, this explanation obscures much of what baluns are actually doing. In reality, they take a three-wire system (the coax) and convert it to a two-wire system (the antenna), which keeps all of the electrical noise and current on the shield wire of the coax from interfering with the desirable RF on the interior of the coax.

This might seem somewhat confusing on the surface, as coax wires only have a center conductor and a shield wire, but thanks to the skin effect which drives currents to the outside of the conductor, the shield wire effectively becomes two conductors when taking into account its inner and outer surfaces. At these high frequencies the balun is acting as a choke which keeps these two high-frequency conductors separate from one another, and keeps all the noise on the outside of the shield wire and out of the transmitter or receiver.

Granted, the world of high-frequency radio circuits can get quite complex and counter-intuitive and, as we’ve shown before, can behave quite unexpectedly when compared to DC or even mains-frequency AC. But a proper understanding of baluns and other types of transformers and the ways they interact with RF can be a powerful tool to have. We’eve even seen other hams use specialty transformers like these to make antennas out of random lengths and shapes of wire.

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Hackaday Prize 2023: Tiny RC Aircraft Built Using Foam And ESP12

April 29, 2023 by Lewin Day 13 Comments

Once upon a time, a radio controlled plane was a hefty and complex thing. They required small nitro engines, support equipment, and relatively heavy RC electronics. Times have changed since then, as this lightweight RC build from [Ravi Butani] demonstrates.

The body of the plane is lightweight foam, and can be assembled in two ways. There’s a relatively conventional layout, using a main wing, tailplane, and rudder, or a pusher model with the main wing at the rear and a canard up front. The open hardware electronics package, which [Ravi] calls VIMANA, consists of an ESP12 module with a pair of MOSFETs to act as two independent motor drivers — allowing the plane to be flown and steered with differential thrust.

For more advanced flight control, it can also command a pair of servos to control ailerons, a rudder, canards, or elevons, depending on configuration. There’s also potential to install an IMU to set the plane up with flight stabilization routines.

Thanks to the low-cost of the VIMANA board, [Ravi] hopes it can be used in STEM education programs. He notes that it’s not limited just to aircraft, and could be used for other motorized projects such as boats and cars. We’ve featured an early version of his work before, but the project has come a long way since then.

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The World’s First Agricultural Right To Repair Law

April 29, 2023 by Jenny List 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.

Building A WiFi Picture Frame With An EInk Display

April 29, 2023 by Lewin Day 6 Comments

LCD photo frames never really caught on — by emitting light, they didn’t seamlessly blend in with a home’s decor in the way printed photos do. [Sprite_tm] decided to see if a color e-Ink screen could do any better, and whipped up a WiFi-enabled photo frame using a Waveshare display.

The part in question is a 5.65-inch display with 640 x 448 resolution, and is capable of displaying seven colors. It’s not designed to display photorealistic images, so much as display simple graphics with block colors. However, with some dithering, [Sprite_tm] suspected it might do an okay job. An algorithm that uses Floyd-Steinberg diffusion and the CIEDE2000 color space takes regular RGB images and breaks them down into dithered images that are displayed using the screen’s 7 available colors.

The build relies on an ESP32-C3, which drives the display and fetches new images daily over WiFi. Thanks to the e-Ink screen, which uses zero power when not updating, the whole setup runs off two AA batteries and a Natlinear LN2266 boost converter.

There are some limitations; the screen’s color space is altogether quite limited, and images don’t look very high-fidelity in such low resolution. However, it does an able job of displaying photos for a device that was never designed to do so. It looks rather handsome all wrapped up as a 3D printed picture frame, and [Sprite_tm]’s monkey test photos are very cute.

Files are on GitHub for those that wish to roll their own. We’ve seen similar works before, like this e-Ink wall-hanging newspaper display that keeps up with the times. If you’ve got your own neat e-ink build, hit us up on the tipsline!

Thinking Inside The Box

April 29, 2023 by Elliot Williams 144 Comments

Last week, I wrote about NASA’s technology demonstrator projects, and how they’ve been runaway successes – both the Mars rovers and the current copter came from such experimental beginnings. I argued that letting some spirit of experimentation into an organization like NASA is probably very fruitful from time to time.

And then a few days later, we saw SpaceX blow up a rocket and completely shred its launch platform in the process. Or maybe it was the other way around, because it looks like the concrete thrown up by the exhaust may have run into the engines, causing the damage that would lead to the vehicle spinning out of control. SpaceX was already working on an alternative launch pad using water-cooled steel, but it ran what it had. They’re calling the mission a success because of what they learned, but it’s clearly a qualified success. They’ll rebuild and try again.

In comparison, the other US-funded rocket run by Boeing, the SLS suffered years of delays, cost tremendous amounts of money, and has half the lift of SpaceX’s Super Heavy. But it made it to space. Science was done, many of the CubeSats onboard got launched, the unmanned capsule orbited the moon, and splashed down safely back on earth. They weren’t particularly taking any big risks, but they got the job done.

The lore around SpaceX is that they’re failing forward to success. And it’s certainly true that they’ve got their Falcon 9 platform down to a routine, at a lower cost per launch than was ever before possible, and that their pace has entirely shaken up the conservative space industry. They’ll probably get there with their Starship / Super Heavy too. SLS was an old-school rocket, and they had boring old flame diverters on their launch pad, which means that SLS will never take off from Mars. On the other hand, one of the two systems has put a payload around the Moon.

Maybe there’s something to be said for thinking inside the box from time to time as well?

Alternatives To Pins And Holes For 3D Printed Assemblies

April 29, 2023 by Lewin Day 35 Comments

When we have two 3D printed parts that need to fit together, many of us rely on pins and holes to locate them and fix them together. [Slant 3D] has explored some alternative ideas in this area that may open up new avenues for your own designs.

Their first idea was to simply chamfer the pins and holes. This allows the object to be printed in a different orientations without compromising the fit. It also makes the features less brittle and creates a broader surface for gluing. Another alternative is using fins and slots, which again add robustness compared to flimsy pins. By chamfering the edges of the fins, they can be printed vertically for good strength and easy location without the need for support material.

Neither option requires much extra fuss compared to typical pin-and-hole designs. Plus, both are far less likely to snap off and ruin your day. Be honest, we’ve all been there. Meanwhile, consider adding folded techniques to your repertoire, too.

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