the water gravity air powered engine running

Gravity-Water-Air Powered Engine

Air engines are a common occurrence here on Hackaday. They’re relatively novel and reasonably easy to 3D print without requiring any fluids or supporting machinery. For example, [Tom Stanton] took a previous air engine design, did away with the air compressor, and instead used gravity and water to create just a few PSI to run the engine.

The basic setup is to have a large jug of water up somewhere high. Flexible tubing runs down to [Tom’s] custom acrylic pressure chamber. A little CNC-ing and some epoxy made a solid chamber, and we’re happy to report that [Tom] did some initial simulation before construction to make sure he wasn’t accidentally building a bomb. Some back of the napkin math showed that he could expect around 0.6 bar (around eight psi) with his setup. His first test showed almost precisely that. Unfortunately, [Tom] ran into some issues despite the early success. His engine would stop as it drew air and the pressure dropped, and the replenishing rate of the pressure was limited by the relatively small inlet hole he had drilled.

To fix this, he printed a larger diaphragm for the engine, so the lower air pressure had more to push against. This allowed the engine to run for a good while before the tank filled up. Additionally, he smoothed and polished everything, so it was as low friction as possible. We know we often state it here, but it is incredible what can be achieved with 3D printed parts these days.

We love seeing the iteration evident in this video. The various engine versions splayed across the table offer a powerful story about [Tom’s] persistence. Powering an engine is a small step to powering your whole home.

Continue reading “Gravity-Water-Air Powered Engine”

Is The IPhone Camera Too Smart? Or Not Smart Enough?

What is a photograph? Technically and literally speaking, it’s a drawing (graph) of light (photo). Sentimentally speaking, it’s a moment in time, captured for all eternity, or until the medium itself rots away. Originally, these light-drawings were recorded on film that had to be developed with a chemical process, but are nowadays often captured by a digital image sensor and available for instant admiration. Anyone can take a photograph, but producing a good one requires some skill — knowing how to use the light and the camera in concert to capture an image.

Eye-Dynamic Range

The point of a camera is to preserve what the human eye sees in a single moment in space-time. This is difficult because eyes have what is described as high dynamic range. Our eyes can process many exposure levels in real time, which is why we can look at a bright sky and pick out details in the white fluffy clouds. But a camera lens can only deal with one exposure level at a time.

In the past, photographers would create high dynamic range images by taking multiple exposures of the same scene and stitching them together.Done just right, each element in the image looks as does in your mind’s eye. Done wrong, it robs the image of contrast and you end up with a murky surreal soup.

Image via KubxLab

Continue reading “Is The IPhone Camera Too Smart? Or Not Smart Enough?”

PCB Thermal Design Hack Chat

Join us on Wednesday, March 30 at noon Pacific for the PCB Thermal Design Hack Chat with Mike Jouppi!

Most of the time, designing a printed circuit board is a little like one of those problems in an introductory physics course, the ones where you can safely ignore things like air resistance. With PCBs, it’s generally safe to ignore things like trace heating and other thermal considerations in favor of just getting everything placed sensibly and routing all the traces neatly.

But eventually, the laws of physics catch up to you, and you’ll come across a real-world problem where you can’t just hand-wave thermal considerations aside. When that happens, you’ll want to have a really good idea of just how much a trace is going to heat up, and what it’s going to do to the performance of your board, or even if the PCB is going to survive the ordeal.

join-hack-chatDigging into the thermal properties of PCBs is something that Mike Jouppi has been doing for years. After working in the aircraft industry as a mechanical engineer, he started Thermal Management LLC, which developed software to make the thermal design of PCBs easier. He’ll stop by the Hack Chat to answer your questions about PCB thermal design considerations, and help us keep all our hard work from going up in smoke.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 30 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.
Continue reading “PCB Thermal Design Hack Chat”

The octagonal wooden box described in the project. On the left, outer surface of the box is shown, with "Say Friend And Come In" inscription, as well as a few draings (presumably from Lord of The Rings) and two metallic color stars that happen to serve as capacitative sensor electrodes. On the right, underside of the lid is shown, with all the electronics involved glued into CNC-machined channels.

Say Friend And Have This Box Open For You

Handcrafted gifts are special, and this one’s no exception. [John Pender] made a Tolkien-inspired box for his son and shared the details with us on Hackaday.io. This one-of-a-kind handcrafted box fulfills one role and does it perfectly – just like with the Doors of Durin, you have to say ‘friend’ in Elvish, and the box shall unlock for you.

This box, carefully engraved and with attention paid to its surface finish, stands on its own as a gift. However, with the voice recognition function, it’s a project complicated enough to cover quite a few fields at once – woodworking, electronics, and software. The electronics are laid out in CNC-machined channels, and LED strips illuminate the “Say Friend And Come In” inscriptions once the box is ready to listen. If you’re wondering how the unlocking process works, the video embedded below shows it all.

Two solenoids keep the lid locked, and in its center is a Pi Zero, the brains of the operation. With small batteries and a power-hungry board, power management is a bit intricate. Two capacitive sensors and a small power management device are always powered up. When both of the sensors are touched, a power switch module from Pololu wakes the Pi up. It, in turn, takes its sweet time, as fully-fledged Linux boards do, and lights up the LED strip once it’s listening.

Continue reading “Say Friend And Have This Box Open For You”

NASA Continues Slow And Steady Pace Towards Moon

It’s often said that the wheels of government turn slowly, and perhaps nowhere is this on better display than at NASA. While it seems like every week we hear about another commercial space launch or venture, projects helmed by the national space agency are often mired by budget cuts and indecisiveness from above. It takes a lot of political will to earmark tens or even hundreds of billions of dollars on a project that could take decades to complete, and not every occupant of the White House has been willing to stake their reputation on such bold ambitions.

In 2019, when Vice President Mike Pence told a cheering crowd at the U.S. Space & Rocket Center that the White House was officially tasking NASA with returning American astronauts to the surface of the Moon by 2024, everyone knew it was an ambitious timeline. But not one without precedent. The speech was a not-so-subtle allusion to President Kennedy’s famous 1962 declaration at Rice University that America would safely land a man on the Moon before the end of the decade, a challenge NASA was able to meet with fewer than six months to spare.

Unfortunately, a rousing speech will only get you so far. Without a significant boost to the agency’s budget, progress on the new Artemis lunar program was limited. To further complicate matters, less than a year after Pence took the stage in Huntsville, there was a new President in the White House. While there was initially some concern that the Biden administration would axe the Artemis program as part of a general “house cleaning”, it was allowed to continue under newly installed NASA Administrator Bill Nelson. The original 2024 deadline, at this point all but unattainable due to delays stemming from the COVID-19 pandemic, has quietly been abandoned.

So where are we now? Is NASA in 2022 any closer to returning humanity to the Moon than they were in 2020 or even 2010? While it might not seem like it from an outsider’s perspective, a close look at some of the recent Artemis program milestones and developments show that the agency is at least moving in the right direction.

Continue reading “NASA Continues Slow And Steady Pace Towards Moon”

Low Power Mode For Custom GPS Tracker

GPS has been a game-changing technology for all kinds of areas. Shipping, navigation, and even synchronization of clocks have become tremendously easier thanks to GPS. As a result of its widespread use, the cost of components is also low enough that almost anyone can build their own GPS device, and [Akio Sato] has taken this to the extreme with efforts to build a GPS tracker that uses the tiniest amount of power.

This GPS tracker is just the first part of this build, known as the air station. It uses a few tricks in order to get up to 30 days of use out of a single coin cell battery. First, it is extremely small and uses a minimum of components. Second, it uses LoRa, a low-power radio networking method, to communicate its location to the second part of this build, the ground station. The air station grabs GPS information and sends it over LoRa networks to the ground station which means it doesn’t need a cellular connection to operate, and everything is bundled together in a waterproof, shock-resistant durable case.

[Akio Sato] imagines this unit would be particularly useful for recovering drones or other small aircraft that can easily get themselves lost. He’s started a crowdfunding page for it as well. With such a long battery life, it’s almost certain that the operator could recover their vessel before the batteries run out of energy. It could also be put to use tracking things that have a tendency to get stolen.

the RP2040 stamp

Putting The RP2040 On A Stamp

In the electronics world, a little one-inch square board with castellated edges allows a lot of circuitry to be easily added in a small surface area. You can grab a prepopulated module, throw it onto your PCB of choice, and save yourself a lot of time routing and soldering. This tiny Raspberry Pi 2040 module from [SolderParty] ticks all those boxes.

With all 30 GPIO broken out, 8MB of onboard flash, and a NeoPixel onboard, you have plenty to play with on top of the already impressive specs of the RPi2040. Gone are the days of in-circuit programmers, and it uses a UF2 bootloader to make it easy B to transfer new images over USB. Rust, MicroPython, Arduino, and the PicoSDK are all development options for code. All the KiCad files, BOM, schematics, and firmware are up on GitHub under a CERN license for your perusal pleasure. They’ve helpfully included footprints as well as a reference carrier board design.

It is a handy little project that might be good to keep in mind or just use as a reference design for your efforts. We have a good overview of the RPi2040 from an STM perspective. If you’re curious about what you could even use this little stamp for, why not driving an HDMI signal?