There’s A New Reusable Rocket, And It’s A Honda

June 24, 2025 by Jenny List 18 Comments

As we watched the latest SpaceX Starship rocket test end in a spectacular explosion, we might have missed the news from Japan of a different rocket passing a successful test. We all know Honda as a car company but it seems they are in the rocket business too, and they successfully tested a reusable rocket. It’s an experimental 900 kg model that flew to a height of 300 m before returning itself to the pad, but it serves as a valuable test platform for Honda’s take on the technology.

It’s a research project as it stands, but it’s being developed with an eye towards future low-cost satellite launches rather than as a crew launch platform.As a news story though it’s of interest beyond its technology, because it’s too easy to miss news from the other side of the world when all eyes are looking at Texas. It’s the latest in a long line of interesting research projects from the company, and we hope that this time they resist the temptation to kill their creation rather than bring it to market.

Building A Custom Paper Tape Punch Machine

June 23, 2025 by Maya Posch 14 Comments

The solenoid and punch side of the machine. {Credit: Simon Boak)

Although [Simon Boak] had no use for an automatic paper tape punch, this was one of those intrusive project thoughts that had to be put to rest. With not a lot of DIY projects to look at, the first step was to prototype a punch mechanism that would work reliably. This involved the machining of a block of aluminium with holes at the right locations for the punch (HSS rods) to push through and create holes into the paper without distortions. Next was to automate this process.

To drive the punches, 12V solenoids were selected, but using leverage to not require the solenoids to provide all the force directly. On the electronics side this then left designing a PCB with the solenoid drivers and an Arduino Nano-style board as the brains, all of which including the Arduino source can be found on GitHub. Much like with commercial tape punch machines, this unit receives the data stream via the serial port (and optional parallel port), with the pattern punched into the 1″ paper tape.

One issue was finding blank paper tape, for which [Simon] cut up rolls of thermal paper using a 3D-printed rig with appropriately installed sharp blades. This paper tape seems to work quite well so far, albeit with the compromise that due to the current drawn by each solenoid (~1.7A) only one solenoid gets activated at any time. This makes it slower than commercial punch machines.

Thanks to [Tim] for the tip.

Add TouchTone Typing To Your Next Project

June 23, 2025 by Al Williams 4 Comments

The Blackberry made phones with real keyboards popular, and smartphones with touch keyboards made that input method the default. However, the old flip phone crowd had just a few telephone keys to work with. If you have a key-limited project, maybe check out the libt9 library from [FoxMoss].

There were two methods for using these limited keyboards, both of which relied on the letters above a phone key’s number. For example, the number 2 should have “ABC” above it, or, sometimes, below it.

In one scheme, you’d press the two key multiple times quickly to get the letter you wanted. One press was ‘2’ while two rapid presses made up ‘A.’ If you waited too long, you were entering the next letter (so pressing two, pausing, and pressing it again would give you ’22’ instead of ‘A’).

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Modern Tech Meets Retro 7-Segment

June 23, 2025 by Matt Varian 7 Comments

At one point in time mechanical seven segment displays were ubiquitous, over time many places have replaced them with other types of displays. [Sebastian] has a soft spot for these old mechanically actuated displays and has built an open-source 7-segment display with some very nice features.

We’ve seen a good number of DIY 7-segment displays on this site before, the way [Sebastian] went about it resulted in a beautiful well thought out result. The case is 3D printed, and although there are two colors used it doesn’t require a multicolor 3d printer to make your own. The real magic in this build revolves around the custom PCB he designed. Instead of using a separate electromagnets to move each flap, the PCB has coil traces used to toggle the flaps. The smart placement of a few small screws allows the small magnets in each flap to hold the flap in that position even when the coils are off, greatly cutting down the power needed for this display. He also used a modular design where one block has the ESP32 and RTC, but for the additional blocks those components can remain unpopulated.

The work he put into this project didn’t stop at the hardware, the software also has a great number of thoughtful features. The ESP32 running the display hosts a website which allows you to configure some of the many features: the real-time clock, MQTT support, timer, custom API functions, firmware updates. The end result is a highly customizable, display that sounds awesome every time it updates. Be sure to check out the video below as well as his site to see this awesome display in action. Also check out some of the other 7-segment displays we’ve featured before.

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Casting Time: Exploded Watch In Resin

June 23, 2025 by Matt Varian 12 Comments

We’ve all seen the exploded view of complex things, which CAD makes possible, but it’s much harder to levitate parts in their relative positions in the real world. That, however, is exactly what [fellerts] has done with this wristwatch, frozen in time and place.

Inspired by another great project explaining the workings of a mechanical watch, [fellerts] set out to turn it into reality. First, he had to pick the right watch movement to suspend. He settled on a movement from the early 1900s—complex enough to impress but not too intricate to be impractical. The initial approach was to cast multiple layers that stacked up. However, after several failed attempts, this was ruled out. He found that fishing line was nearly invisible in the resin. With a bit of heat, he could turn it into the straight, transparent standoffs he needed.

Even after figuring out the approach of using fishing line to hold the pieces at the right distance and orientation, there were still four prototypes before mastering all the variables and creating the mesmerizing final product. Be sure to head over to his site and read about his process, discoveries, and techniques. Also, check out some of the other great things we’ve seen done with epoxy in the past.

Keep Track Of The Compost With LoRaWAN

June 23, 2025 by Tyler August 7 Comments

Composting doesn’t seem difficult: pile up organic matter, let it rot. In practice, however, it’s a bit more complicated– if you want that sweet, sweet soil amendment in a reasonable amount of time, and to make sure any food-born pathogens and weed seeds don’t come through, you need a “hot” compost pile. How to tell if the pile is hot? Well, you could go out there and stick your arm in like a schmuck, or you could use [Dirk-WIllem van Gulik]’s “LORAWAN Compostheap solarpowered temperaturesensor” (sic).

The project is exactly what it sounds like, once you add some spaces: a solar-powered temperature sensor that uses LoRaWAN to track temperatures inside (and outside, for comparison) the compost heap year round. Electronically it is pretty simple: a Helltech CubeCell AB01 LoraWAN module is wired up with three DS18B20 temperature sensors, a LiPo battery and a solar panel. (The AB01 has the required circuitry to charge the battery via solar power.) Continue reading “Keep Track Of The Compost With LoRaWAN” →

Video Game Preservation Through Decompilation

June 23, 2025 by Tom Nardi 18 Comments

Unlike computer games, which smoothly and continuously evolved along with the hardware that powered them, console games have up until very recently been constrained by a generational style of development. Sure there were games that appeared on multiple platforms, and eventually newer consoles would feature backwards compatibility that allowed them to play select titles from previous generations of hardware. But in many cases, some of the best games ever made were stuck on the console they were designed for.

Now, for those following along as this happened, it wasn’t such a big deal. For gamers, it was simply a given that their favorite games from the Super Nintendo Entertainment System (SNES) wouldn’t play on the Nintendo 64, any more than their Genesis games could run on their Sony PlayStation. As such, it wasn’t uncommon to see several game consoles clustered under the family TV. If you wanted to go back and play those older titles, all you had to do was switch video inputs.

But gaming, and indeed the entertainment world in general, has changed vastly over the last couple of decades. Telling somebody today that the only way they can experience The Legend of Zelda: A Link to the Past is by dragging out some yellowed thirty-odd year old console from the attic is like telling them the only way they can see a movie is by going to the theater.

These days, the expectation is that entertainment comes to you, not the other way around — and it’s an assumption that’s unlikely to change as technology marches on. Just like our TV shows and movies now appear on whatever device is convenient to us at the time, modern gamers don’t want to be limited to their consoles, they also want to play games on their phones and VR headsets.

But that leaves us with a bit of a problem. There are some games which are too significant, either technically or culturally, to just leave in the digital dust. Like any other form of art, there are pieces that deserve to be preserved for future generations to see and experience.

For the select few games that are deemed worth the effort, decompilation promises to offer a sort of digital immortality. As several recent projects have shown, breaking a game down to its original source code can allow it to adapt to new systems and technologies for as long as the community wishes to keep them updated.

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