A Bicycle Is Abandonware Now? Clever Hack Rescues Dead Light

April 24, 2025 by Jenny List 77 Comments

A bicycle is perhaps one of the most repairable pieces of equipment one can own — no matter what’s wrong with it, and wherever you are on the planet, you’ll be able to find somebody to fix your bike without too much trouble. Unfortunately as electric bikes become more popular, predatory manufacturers are doing everything they can to turn a bike into a closed machine, only serviceable by them.

That’s bad enough, but it’s even worse if the company happens to go under. As an example, [Fransisco] has a bike built by a company that has since gone bankrupt. He doesn’t name them, but it looks like a VanMoof to us. The bike features a light built into the front of the top tube of the frame, which if you can believe it, can only be operated by the company’s (now nonfunctional) cloud-based app.

The hack is relatively straightforward. The panel for the VanMoof electronics is removed and the works underneath are slid up the tube, leaving the connector to the front light. An off the shelf USB-C Li-Po charger and a small cell take the place of the original parts under a new 3D printed panel with a switch to run the light via a suitable resistor. If it wasn’t for the startling green color of the filament he used, you might not even know it wasn’t original.

We would advise anyone who will listen, that hardware which relies on an app and a cloud service should be avoided at all costs. We know most Hackaday readers will be on the same page as us on this one, but perhaps it’s time for a cycling manifesto to match our automotive one.

Thanks [cheetah_henry] for the tip.

From PostScript To PDF

April 24, 2025 by Al Williams 35 Comments

There was a time when each and every printer and typesetter had its own quirky language. If you had a wordprocessor from a particular company, it worked with the printers from that company, and that was it. That was the situation in the 1970s when some engineers at Xerox Parc — a great place for innovation but a spotty track record for commercialization — realized there should be a better answer.

That answer would be Interpress, a language for controlling Xerox laser printers. Keep in mind that in 1980, a laser printer could run anywhere from $10,000 to $100,000 and was a serious investment. John Warnock and his boss, Chuck Geschke, tried for two years to commercialize Interpress. They failed.

So the two formed a company: Adobe. You’ve heard of them? They started out with the idea of making laser printers, but eventually realized it would be a better idea to sell technology into other people’s laser printers and that’s where we get PostScript.

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Haptic Soft Buttons Speak(er) To Your Sense Of Touch

April 24, 2025 by Tyler August 7 Comments

There’s just something about a satisfying “click” that our world of touchscreens misses out on; the only thing that might be better than a good solid “click” when you hit a button is if device could “click” back in confirmation. [Craig Shultz] and his crew of fine researchers at the Interactive Display Lab at the University of Illinois seem to agree, because they have come up with an ingenious hack to provide haptic feedback using readily-available parts.

The “hapticoil”, as they call it, has a simple microspeaker at its heart. We didn’t expect a tiny tweeter to have the oomph to produce haptic feedback, and on its own it doesn’t, as finger pressure stops the vibrations easily. The secret behind the hapticoil is to couple the speaker hydraulically to a silicone membrane. In other words, stick the thing in some water, and let that handle the pressure from a smaller soft button on the silicone membrane. That button can be virtually any shape, as seen here.

Aside from the somewhat sophisticated electronics that allow the speaker coil to be both button and actuator (by measuring inductance changes when pressure is applied, while simultaneously driven as a speaker), there’s nothing here a hacker couldn’t very easily replicate: a microspeaker, a 3D printed enclosure, and a silicone membrane that serves as the face of the haptic “soft button”. That’s not to say we aren’t given enough info replicate the electronics; the researchers are kind enough to provide a circuit diagram in figure eight of their paper.

In the video below, you can see a finger-mounted version used to let a user feel pressing a button in virtual reality, which raises some intriguing possibilities. The technology is also demonstrated on a pen stylus and a remote control.

This isn’t the first time we’ve featured hydraulic haptics — [Craig] was also involved with an electroosmotic screen we covered previously, as well as a glove that used the same trick. This new microspeaker technique does seem much more accessible to the hacker set, however.

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The Mohmmeter: A Steampunk Multimeter

April 24, 2025 by Matt Varian 12 Comments

[Agatha] sent us this stunning multimeter she built as a gift for her mom. Dubbed the Mohmmeter — a playful nod to its ohmmeter function and her mom — this project combines technical ingenuity with heartfelt craftsmanship.

At its core, a Raspberry Pi Pico microcontroller reads the selector knob, controls relays, and lights up LEDs on the front panel to show the meter’s active range. The Mohmmeter offers two main measurement modes, each with two sub-ranges for greater precision across a wide spectrum.

She also included circuitry protections against reverse polarity and over-voltage, ensuring durability. There was also a great deal of effort put into ensuring it was accurate, as the device was put though its paces using a calibrated meter as reference to ensure the final product was as useful as it was beautiful.

The enclosure is a work of art, crafted from colorful wooden panels meticulously jointed together. Stamped brass plates label the meter’s ranges and functions, adding a steampunk flair. This thoughtful design reflects her dedication to creating something truly special.

Want to build a meter for mom, but she’s more of the goth type? The blacked-out Hydameter might be more here style.

C64 Assembly In Parts

April 23, 2025 by Al Williams 19 Comments

[Michal Sapka] wanted to learn a new skill, so he decided on the Commodore 64 assembly language. We didn’t say he wanted to learn a new skill that might land him a job. But we get it and even applaud it. Especially since he’s written a multi-part post about what he’s doing and how you can do it, too. So far, there are four parts, and we’d bet there are more to come.

The series starts with the obligatory “hello world,” as well as some basic setup steps. By part 2, you are learning about registers and numbers. Part 3 covers some instructions, and by part 4, he finds that there are even more registers to contend with.

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Improved And Open Source: Non-Planar Infill For FDM

April 23, 2025 by Heidi Ulrich 16 Comments

Strenghtening FDM prints has been discussed in detail over the last years. Solutions and results vary as each one’s desires differ. Now [TenTech] shares his latest improvements on his post-processing script that he first created around January. This script literally bends your G-code to its will – using non-planar, interlocking sine wave deformations in both infill and walls. It’s now open-source, and plugs right into your slicer of choice: PrusaSlicer, OrcaSlicer, or Bambu Studio. If you’re into pushing your print strength past the limits of layer adhesion, but his former solution wasn’t quite the fit for your printer, try this improvement.

Traditional Fused Deposition Modeling (FDM) prints break along layer lines. What makes this script exciting is that it lets you introduce alternating sine wave paths between wall loops, removing clean break points and encouraging interlayer grip. Think of it as organic layer interlocking – without switching to resin or fiber reinforcement. You can tweak amplitude, frequency, and direction per feature. In fact, the deformation even fades between solid layers, allowing smoother transitions. Structural tinkering at its finest, not just a cosmetic gimmick.

This thing comes without needing a custom slicer. No firmware mods. Just Python, a little G-code, and a lot of curious minds. [TenTech] is still looking for real-world strength tests, so if you’ve got a test rig and some engineering curiosity, this is your call to arms.

The script can be found in his Github. View his full video here , get the script and let us know your mileage!

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Abusing DuckDB-WASM To Create Doom In SQL

April 23, 2025 by Maya Posch 9 Comments

These days you can run Doom anywhere on just about anything, with things like porting Doom to JavaScript these days about as interesting as writing Snake in BASIC on one’s graphical calculator. In a twist, [Patrick Trainer] had the idea to use SQL instead of JS to do the heavy lifting of the Doom game loop. Backed by the Web ASM version of the analytical DuckDB database software, a Doom-lite clone was coded that demonstrates the principle that anything in life can be captured in a spreadsheet or database application.

Rather than having the game world state implemented in JavaScript objects, or pixels drawn to a Canvas/WebGL surface, this implementation models the entire world state in the database. To render the player’s view, the SQL VIEW feature is used to perform raytracing (in SQL, of course). Any events are defined as SQL statements, including movement. Bullets hitting a wall or impacting an enemy result in the bullet and possibly the enemy getting DELETE-ed.

The role of JavaScript in this Doom clone is reduced to gluing the chunks of SQL together and handling sprite Z-buffer checks as well as keyboard input. The result is a glorious ASCII-based game of Doom which you can experience yourself with the DuckDB-Doom project on GitHub. While not very practical, it was absolutely educational, showing that not only is it fun to make domain specific languages do things they were never designed for, but you also get to learn a lot about it along the way.

Thanks to [Particlem] for the tip.