A pinhole camera is essentially the combination of the camera obscura with photographic film. The pinhole acts as the lens, focusing the scene onto the film, and after exposure, the film can then be developed and you’ve got your picture. They’re a fun way to learn about photography, and easy to make, too. [Brooklyntonia] decided to undertake just such a build, secreted away inside a pocket watch.
The build starts with with the disassembly of the watch, which acts as the main cavity of the camera. A bellows is then constructed from leather and a toilet paper roll to allow the camera to still fold up inside the original watch case. A pinhole is then installed at the end of the bellows, and a plug is used as a shutter to allow the bellows to be properly unfolded prior to exposure.
It’s a fun build, and one that comes complete with instructions for the proper processing of film in your own darkroom – or bathroom. Pinhole cameras can be useful tools, too – particularly for things such as capturing an eclipse.
One of the most artistic applications of electrical engineering in recent memory is the burgeoning badgelife movement. This is an odd collective of people who are dedicating their time to rendering their own accomplishments in printed circuit boards. Of the entire badgelife collective, one of the most visible efforts are in Shitty Add-Ons, with a particular focus on reverse-mounted LEDs. Yes, you can install SMD LEDs upside down, and if you have your copper layers right, the light will shine through the badge.
One of the most prominent users of reverse mounted LEDs is [TwinkleTwinkie], and now finally we have a writeup on the science of reverse mounted LEDs. There’s a lot to unpack here, so buckle up and prepare to burn the tips of your fingers on a soldering iron.
For truly reverse-mounted PCBs, there are two options. The first, and most expensive, are ‘reverse gullwing’ LEDs. These LEDs are just like normal LEDs, except the SMD pads are reversed, allowing you to mount it so the light shines into the PCB. These LEDs are expensive, rare (only three companies make them), and they don’t really give off a lot of light. The other solution to reverse-mounting a LED is simply taking a standard 1206 SMD LED and manually soldering it upside-down. This is not pick and place friendly, although I’m sure you could find an LED manufacture that would put LEDs in reels upside-down if you want.
Side view LEDs
The takeaway for reverse mount LEDs is pick two: good, fast, or cheap. Reverse gullwing LEDs are expensive, but can be pick and placed and provide sufficient illumination. Hand-soldered LEDs installed upside down are cheap, slow, but also good.
But there is another option. Side view LEDs are a thing, and they can be pick and placed. You can get them in every color, and even UV. [Twinkle] has experimented with side-view LEDs in place of reverse mounted LEDs, and the results are promising. By putting the side view LED next to part of a PCB without copper or soldermask, there is some light bleed through the PCB. It’s somewhat uneven, but with a hot melt glue diffusor, you can get a somewhat decent bar of light being emitted through a PCB.
If you want to put blinky on a PCB, you have a lot of options. If you want to put blinky on a PCB without having any visible light source, these are your options. This is the state of the art in artistic PCBs, and we’re so glad [Twinkle] could share it with us.
An eggbot is probably the easiest introduction to CNC machines that you could possibly hope for, at least in terms of the physical build. But at the same time, an eggbot can let you get your hands dirty with all of the concepts, firmware, and the toolchain that you’d need to take your CNC game to the next level, whatever that’s going to be. So if you’ve been wanting to make any kind of machine where stepper motors move, cut, trace, display, or simply whirl around, you can get a gentle introduction on the cheap with an eggbot.
Did we mention Easter? It’s apparently this weekend. Seasonal projects are the worst for the procrastinator. If you wait until the 31st to start working on your mega-awesome New Year’s Dropping Laser Ball-o-tron 3000, it’s not going to get done by midnight. Or so I’ve heard. And we’re certainly not helping by posting this tutorial so late in the season. Sorry about that. On the other hand, if you start now, you’ll have the world’s most fine-tuned eggbot for 2020. Procrastinate tomorrow!
I had two main goals with this project: getting it done quickly and getting it done easily. That was my best shot at getting it done at all. Secondary goals included making awesome designs, learning some new software toolchains, and doing the whole thing on the cheap. I succeeded on all counts, and that’s why I’m here encouraging you to build one for yourself.
KiCad is the electronic design automation software that lives at the intersection of electronic design and open source software. It’s seen a huge push in development over the last few years which has grown the suite into a mountain of powerful tools. To help better navigate that mountain, the first ever KiCad conference, KiCon, is happening next week in Chicago and Hackaday is hosting one of the afterparties.
The two days of talks take place on April 26th and 27th covering a multitude of topics. KiCad’s project leader, Wayne Stambaugh, will discuss the state of the development effort. You’ll find talks on best practices for using the software as an individual and as a team, how to avoid common mistakes, and when you should actually try to use the auto-router. You can learn about automating your design process with programs that generate footprints, by connecting it through git, and through alternate user interfaces. KiCad has 3D modeling to make sure your boards will fit their intended enclosures and talks will cover generating models in FreeCAD and rendering designs in both Fusion360 and Blender. Dust off your dark arts with RF and microwave design tips as well as simulating KiCad circuits in SPICE. If you can do it in KiCad, you’ll learn about it at KiCon.
Of course there’s a ton of fun to be had as interesting hackers from all over the world come together in the Windy City. Hackaday’s own Anool Mahidharia and Kerry Scharfglass will be presenting talks, and Mike Szczys will be in the audience. We anticipate an excellent “lobby con” where the conversations away from the stages are as interesting as the formal talks. And of course there are afterparties!
Friday 4/26 Pumping Station: One, the popular Chicago hackerspace now celebrating its 10 year anniversary, is hosting an afterparty (details TBA)
Saturday 4/27: Hackaday is hosting an after party at Jefferson Tap from 6-8:30. We’re providing beverages and light food for all who attended the conference.
If you still don’t have a ticket to KiCon, you better get one right now. We’re told that you can count what’s left on two hands. Supplyframe (Hackaday’s parent company) is a sponsor of KiCon, and we have two extra tickets that came with that sponsorship. We like seeing a diverse community at these events and have saved these tickets for people from under-represented groups (such as for example women, LGBT+, and people of color) in the hardware world. Email us directly for the tickets, your information will remain confidential.
We’re looking forward to seeing everyone next week!
Typically, when one considers writing a video game, the platform is among the first decisions to be made. The PC can be an easy one to start with, and mobile development is fairly accessible too. Of course, you could always develop for a microcontroller platform instead. [Fabrizio Di Vittorio] has built the perfect set of tools to do just that with the ESP32, by the name of FabGL.
The library contains a laundry list of features that are perfect for developing games. There’s VGA output with up to 64 colors, PS/2 mouse and keyboard inputs, as well as a capable graphics library and game engine. It can even act as an ANSI/VT terminal if necessary.
[Fabrizio] has put the hardware through its paces, with a variety of benchmarks displaying impressive performance with simple balls, polygons and sprites. You could easily produce a 2D game in an early 90s style without running into any hardware limitations — though given the ESP32 clocks in at up to 240MHz, that’s somewhat to be expected.
It’s an impressive project (video after the break), and we’d love to see more games developed on the platform. Once you have a VGA connector wired in you should try out some ESP32 VGA hacks. And for those ESP8266 die hards there’s a game engine for that chip too!
In the era of social media, events such as the fire at Notre Dame cathedral are experienced by a global audience in real-time. From New York to Tokyo, millions of people were glued to their smartphones and computers, waiting for the latest update from media outlets and even individuals who were on the ground documenting the fearsome blaze. For twelve grueling hours, the fate of the 850 year old Parisian icon hung in the balance, and for a time it looked like the worst was inevitable.
The fires have been fully extinguished, the smoke has cleared, and in the light of day we now know that the heroic acts of the emergency response teams managed to avert complete disaster. While the damage to the cathedral is severe, the structure itself and much of the priceless art inside still remain. It’s far too early to know for sure how much the cleanup and repair of the cathedral will cost, but even the most optimistic of estimates are already in the hundreds of millions of dollars. With a structure this old, it’s likely that reconstruction will be slowed by the fact that construction techniques which have become antiquated in the intervening centuries will need to be revisited by conservators. But the people of France will not be deterred, and President Emmanuel Macron has already vowed his country will rebuild the cathedral within five years.
It’s impossible to overstate the importance of the men and women who risked their lives to save one of France’s most beloved monuments. They deserve all the praise from a grateful nation, and indeed, world. But fighting side by side with them were cutting-edge pieces of technology, some of which were pushed into service at a moments notice. These machines helped guide the firefighters in their battle with the inferno, and stood in when the risk to human life was too great. At the end of the day, it was man and not machine that triumphed over nature’s fury; but without the help of modern technology the toll could have been far higher.
The common magnetic loudspeaker is, fundamentally, a fairly simple machine. A static magnetic field is generated by a permanent magnet, and a membrane is mechanically connected to a coil. When a varying electrical current is passed through the coil, this causes the coil to move due to the magnetic field, vibrating the membrane and producing sound. [Mattosx] put this theory into practice with a simple 3D-printed speaker.
It’s not the first 3D-printed speaker we’ve ever seen, but it’s one of the cutest. The main body of the speaker is rectangular, and has a cavity in which three neodymium magnets are placed. The vibrating membrane is then printed separately, including an integrated spindle upon which the coil is wound. The assembly is held together with some socket-head cap screws which complement the pleasantly modern look.
The device does a good job delivering the bleeps when hooked up to an Arduino, and we could see this basic design serving well in all manner of charming 3D-printed builds. Video after the break.
