[Oscar] wonders why hobby projects ignore all the powerful brushless motors available for far less than the equivalent stepper motors, especially with advanced techniques available to overcome their deficiencies. He decided it must be because there is simply not a good, cheap, open source motor controller out there to drive them precisely. So, he made one.
Stepper motors are good for what they do, open-loop positioning along a grid, but as far as industrial motors go they’re really not the best technology available. Steppers win on the cost curve for being uncomplicated to manufacture and easy to control, but when it comes to higher-end automation it’s servo control all the way. The motors are more powerful and the closed-loop control can be more precise, but they require more control logic. [Oscar]’s board is designed to fill in this gap and take full advantage of this motor control technology.
The board can do some pretty impressive things for something with a price goal under $50 US dollars. It supports two motors at 24 volts with up to 150 amps peak current. It can take an encoder input for full closed loop control. It supports battery regeneration for braking. You can even augment a more modest power supply to allow for the occasional 1 KW peak movement with the addition of a lithium battery. You can see the board showing off some of its features in the video after the break.The HackadayPrize2016 is Sponsored by:
Filed under: cnc hacks, The Hackaday Prize
This is a super fun hack that’s been around for ages — but now with cheap full 1080P HD camera availability, it’s probably a good time to make your own infrared camera!
It’s actually a very easy modification to perform. All cameras are capable of “seeing” infrared light, but for standard photography and video, you don’t want to see the infrared light. So most sensors just have an infrared filter in front of the sensor, to block out any excess infrared light. If you remove it … you have a converted infrared camera.
The following video shows exactly how to modify a camera to do this. It is a bit misleading though as it labels it as a thermal camera; and while it is seeing “infrared”, it’s not actually full thermal infrared, like a FLIR or Seek Thermal can see — it’s a mixture of visible and near infrared light. You will be able to see some hot things glowing through the camera, but not to the same degree as a real thermal imaging device.
The coolest part is a lot of black plastic is transparent to infrared light, meaning you can see through it with the camera!
Filed under: digital cameras hacks
It is likely that many of us will at some time have experimented with motion detectors. Our Arduinos, Raspberry Pis, Beaglebones or whatever will have been hooked up to ultrasonic or PIR boards which will have been queried for their view of what is in front of them.
[Connornishijima] has stumbled on a different way to detect motion with an Arduino, he’s polling an ADC pin with a simple length of twisted pair hooked up to it and earth, and reliably generating readings indicating when he (or his cat) is in its vicinity. He’s calling the effect “Capacitive turbulence”, and he’s open to suggestions as to its mechanism. He can only make it work on the Arduino, other boards with ADCs don’t cut it.
Frequent Hackaday featuree [Mitxela] may have also discovered something similar, and we’ve hesitated to write about it because we didn’t understand it, but now it’s becoming unavoidable.
It’s always dangerous in these situations to confidently state your opinion as “It must be…” without experimental investigation of your own. Those of us who initially scoffed at the idea of the Raspberry Pi 2 being light sensitive and later had to eat their words have particular cause to remember this. But this is an interesting effect that bears understanding. We would guess that the Arduino’s fairly high input impedance might make it sensitive to mains hum, if you did the same thing to an audio amplifier with a phono input you might well hear significant hum in the speaker as your hand approached the wire. It would be interesting to try the experiment at an off-grid cabin in the woods, in the absence of mains hum.
If you’d like to give his experiment a try, he’s posted his sketch on Pastebin. And he’s put up the video below the break demonstrating the effect in action, complete with cats.
We like to see people pushing the boundaries of what is possible with their microcontroller I/O lines, it furthers our collective knowledge as a community. We’ve seen people making TV transmitters from ESP8266s, and not so long ago a Raspberry Pi ADC port as further examples. Please, keep them coming!
Filed under: Arduino Hacks, hardware
Some see gaming as the way to make AI work, by teaching computers how to play, and win, at games. This is perhaps one step on the way to welcoming our new gaming overlords: a group of Cornell students used an FPGA to win a computer cricket game. Specifically, they figured out how to use an FPGA to beat the tricky batting portion of the game in a neat way. They used an FPGA that directly samples the VGA output signal from the gaming computer, detecting the image of the meter that indicates the optimum batting time. Once it detects the optimum point to press the button, it triggers a hacked keyboard to press a button, whacking the ball to the boundary to score a six*.
There is a bit more to it than simply detecting a lit pixel, though. The students had to analyze the way the game plays and figure out how to use certain quirks, such as detecting if the batter is left- or right-handed by detecting their white outfit in an area of the screen, then changing the timing to suit. They also had to detect the speed of the ball from the radar indicator. And all of this while the game is running.
This is an impressive example of how useful FPGAs can be: by cleverly analyzing the game, the students worked out how to break it down and create an FPGA program that can use their analysis to win the game. And we love that opto-isolated keyboard hack. Kudos to them for a smart analysis, excellent circuit design and a clever implementation. Now if you’ll excuse me, I’ll be in the pavilion, having tea with our new, cricket-playing overlords.
*For those of you not familiar with cricket, it is like baseball, but at one tenth of the speed, with fewer steroids and more tea.
Filed under: FPGA
The Hackaday Belgrade Conference was an amazing success. For proof, you need look no farther than the slate of talks that we have been publishing over that past several weeks. Each looks at different angles of the hardware universe; what does it mean to create hardware, where have we been, where are we going, and where does inspiration for the next great design come from?
The talks have now all been published and collected into one video playlist; it was an intense day of talks all caught in one streaming frenzy. But if you can’t make it through in one sitting, I’ve also listed the individual talks after the break so you that you may pick and choose.
There are, however, two talks that have just been published this afternoon. These are the opening remarks presented by Aleksandar Bradic and the closing remarks which I presented. When we meet people we’re often asked about what is going on behind the scenes. It’s really easy to think that nobody cares about what it takes to pull together a conference, run an amazing engineering challenge, or how we decide what we think matters when looking to the future. Alek covers the back story of how Supplyframe and Hackaday came together, as well as what led us to choose Belgrade for this conference. I discuss what I think is a core virtue of Hackaday; the free and open sharing of information and ideas. It’s a concept I believe in, and the most noble of reasons for documenting your work so that others may build upon your knowledge and skill.
Hackaday | Belgrade went beyond what we even considered possible. It joins the 2016 SuperConference (whose talk videos have also been published) as a shining example of our strong, active, and engaged community who want to spend their time enabling everyone — hackers, designers, and engineers alike — to succeed.Hackaday | Belgrade Conference Talks
Hackaday would like to extend a special thank you to Milan Maletic for editing all of the talk videos.
The complete talk video playlist includes:
- Opening Remarks: Aleksandar Bradic | video
- One-Armed Embedded: Ending the 8 vs 32 Bit Argument: Mike Szczys | video | article
- Creation, Fabrication…. polarization illumination: Sophi Kravitz | video | article
- Top Down Electronics: Chris Gammell | video | article
- Hackaday Belgrade Badge Hacking: Voja Antonic | video | article
- Forward Futures: Phoenix Perry | video | article
- Long Road to the Internet: Dejan Ristanovic | video | article
- Hacker’s Friendly OSHW DIY Modular Laptop | video | article
- Making the Laser Light Synths: Seb Lee-Delisle | video | article
- How to Eat Your Own Face: Navid Gornall | video | article
- Interactive Digital Storytelling Systems: Paulina Great Stefanovic | video | article
- Open Source Clinical-Grade Electrocardiography: Peter Isza | video | article
- Reinventing the VHDL (badly): Philip Peter | video | article
- Designing a High Performance Parallell Personal Cluster: Kristina Kapanova | video | article
- Retrotechular: 1950s Video Projection Technology: Mike Harrison | video | article
- Closing Remarks: Mike Szczys | video
Filed under: cons, Hackaday Columns
[John Blankenbaker] did not invent the personal computer. Museums, computer historians, and authors have other realities in mind when they say [John]’s invention, the KENBAK-1, was the first electronic, commercially available computer that was not a kit, and available to the general population.
In a way, it’s almost to the KENBAK’s detriment that it is labelled the first personal computer. It was, after all, a computer from before the age of the microprocessor. It is possibly the simplest machine ever sold and an architecturally unique machine that has more in common with the ENIAC than any other machine built in the last thirty years..
The story of the creation of this ancient computer has never been told until now. [John], a surprisingly spry octogenarian, told the story of his career and the development of the first personal computer at the Vintage Computer Festival East last month. This is his story of not inventing the personal computer.A Career of Small Computer Systems
[John] began his career as an intern working at the National Bureau of Standards in Washington, D.C. He was assigned to the SEAC, a project to build a relatively small computer for the US Government before a much larger computer could be completed.
The SEAC was a small computer, but it was not by any means simple. There were over seven hundred vacuum tubes in the racks, tens of thousands of very expensive diodes for all of the logic. The memory was a set of mercury delay lines — tubes, filled with liquid mercury, with acoustic transducers at each end. These transducers would send pings through the mercury, representing zeros or ones. Because of the speed of sound through this mercury, a small amount of information could be stored, like a gigantic shift register.
There were only a handful of instructions available for this computer – addition, subtraction, multiplication, division, comparison, and an instruction for input and output. There weren’t many instructions, but it was enough; SEAC was the first stored program computer in the United States, and the only computer in Washington, D.C. Everything from calculations needed by Los Alamos to navigation tables for the new LORAN network were created on SEAC.
After working for the National Bureau of Standards, [John] moved on to Hughes Aircraft. His work on the SEAC made him extremely valuable for another small computer – an airborne computer, built in 1952. This was only a few years after the development and commercialization of the transistor, and as such this airborne computer used the latest vacuum tubes, arguably the most technologically advanced vacuum tubes ever made. All the memory was contained in a rotating magnetic drum, and most of the logic was implemented with diodes so expensive they were stored in a safe.
This was the very beginning of the computer age, and as such semiconductors were in short supply. Adding a flip-flop to a design meant the cost of this computer would increase by $500. It was the time of small computer systems, and the architectural limitations of early computers wasn’t because they couldn’t build them bigger; these computers were small because anything bigger would cost too much.Building the KENBAK
In 1970, [John] found himself unemployed, with $6000 in his bank account from a severance package. He decided if he was ever going to build a small computer, this was the time. He wanted an educational computer — a machine that would teach people how to use a computer. It would have to be cheap, and something that a single person could operate. A personal computer, if you will.
[John] settled on a very basic computer, with an architecture not unlike the SEAC he built 20 years before. There would be three registers, A, B, and X. Five addressing modes complimented a handful of instructions – add, subtract, load, store, AND, OR, a few jumps, conditionals, I/O, and of course a NOP. The memory would be two shift registers configured as serial memory, a much smaller and less toxic version of SEAC’s mercury delay line memory.The first ad for a personal computer, from Scientific American’s September 1971 issue
With the right architecture in hand, [John] began building his computer. To keep costs low, he went with off-the-shelf parts. The were 132 standard TTL logic ICs, accompanied by two 1024-bit MOS shift registers. The machine had 256 bytes of memory (although the word size was not eight bits), and no ROM. It wasn’t fast, it wasn’t powerful, but anyone could program it by punching ones and zeros into the front panel.
With a design and a few tweaks to the circuit, [John] had a computer. The plan always was to manufacture this computer. That meant sales, and that meant a market.
It’s easy to see the ideal market for the earliest computers would be scientists, academics, and engineers when looking back on nearly fifty years of computer history. Universities were Digital Equipment Corporation’s largest market after the government, after all. [John] designed the KENBAK as a computer trainer, and decided teachers — high school and community college teachers — would be the market where the utility of a personal computer would be apparent.
In May of 1971, [John] trundled out his booth to a convention of high school mathematics teachers nearby. The computer worked, and he had a few programs loaded into the memory, the most memorable of which would give the day of the week for any date in the 1900s. There are eight lights across the face of the KENBAK, and with just a little bit of code, this computer would blink the first light for Monday, the second light for Tuesday, all the way down the line until an invalid date would light up the eighth light.
Apparently, and to [John]’s great surprise, high school mathematics teachers don’t know the rules for the calendar. Nevertheless, he did get a lot of interest from private individuals, colleges, and universities. KENBAKs were shipped around the country, to France, Italy, Mexico, and Canada. Only forty or so KENBAKs were ever sold, with seven units ending up at a technical college in Nova Scotia. Canada.Recognized As The First Personal Computer
In the mid-1980s, long after selling his inventory off and moving across the country to Pennsylvania, The Computer Museum in Boston — the forerunner of the Computer History Museum in Mountain View, California — announced they were trying to find the first personal computer. These submissions (or more cynically; these donations to the museum) would be judged by a panel of technologists including [Woz], [David Bunnell], the publisher of PC World, and [Oliver Strimpel].
Of course, any attempt to find the first personal computer eventually becomes an argument of adjectives. Computers had existed before 1970, going back to [Konrad Zuse]’s Z3, the Colossus at Bletchley Park, or later the programmable ENIAC. These computers were each firsts in their own way, and technically the Computer Museum produced two winners for their ‘first computer’ contest; the French Micral from 1973 was called, “the first commercially available microprocessor based computer.”
The KENBAK, according to the Boston Computer Museum, The Computer History Museum, and [Woz] himself, was the first electronic, commercially available computer that was not a kit and available to the general population.
Of course, [John] will never say he invented the personal computer. He says there were people who had built computers out of logic chips before him. Those people just didn’t commercialize their computers. There were computers sold to the public before the KENBAK, as well. [John] remembers a computer sold by FAO Schwartz that had a drum with pins and holes, and would complete operations in an automated fashion.
“One of the things that people sometimes say about this is that I invented it. I always say there was no invention, it’s just logic, only ones and twos, that’s all it is,” [John] said closing his talk at the Vintage Computer Festival, “there was no radical thing that I invented. I just programmed a computer.”
Filed under: classic hacks, computer hacks, Featured, History
Looking for a high quality security camera? Despite digital cameras continually getting better, and less expensive, security cameras haven’t seemed to follow the same path. So? Better make your own.
[donothingloop] was looking for an outdoor, network capable camera of high resolution. He Some people might have thought about using the Raspberry Pi camera module, but let’s be honest — it’s not great. Instead, he found a pair of used Nikon Coolpix L31 cameras, and he only paid $15 for the both of them.
Now the Nikon Coolpix L31 isn’t exactly the sports edition, so to make this an outdoor security camera, it’s going to need an enclosure. An outdoor halogen work lamp enclosure fit the bill perfectly. It’s rugged, already has the glass built into it, and at $12 the cost of this project wasn’t going anywhere!
To control the camera, he’s still going to be using a Raspberry Pi — it’s one of the most cost effective ways of getting something like a camera feed on the network. He 3D printed some adapters and was able to fit everything inside the lamp enclosure quite nicely — and just look at the quality of the images it records!
Not bad for a project with a BOM cost under $60! For more security camera hacks, check out [Dann Albright’s] experimentation in home security.
Filed under: digital cameras hacks, Raspberry Pi
I make things for people that can’t be bought off a shelf, and in the past several years I have gone through a lot of Arduinos. More and more, they are simply the right tool for both the job and the client. This wasn’t always the case; what changed?
My clients today still include startups and other small businesses, but more and more they’re artists, hobbyists venturing into entrepreneurship, or people who make one-offs like the interactive displays you find in museums or science centers. The type of people I work for has changed, and because of this, the right tool for their job is almost always an Arduino.If Not Arduinos, What?
I was chatting with some new people at a local hackerspace, and we were talking about what we do. I told them I spent a lot of time making one-off devices, prototypes, or small production runs for people who know what they need, but can’t buy it off a shelf. I mentioned that I go through plenty of Arduinos as a result.
“What would you be using if it wasn’t an Arduino?” I was asked.
I thought for a moment and replied something about how I’d probably use an AVR on a board I designed, and roll that out when I needed a microcontroller to do things. I said this because that board was my go-to solution when I needed something for my own projects. There was a nod and the conversation moved on, but after thinking a moment more I realized I had to change my answer.
If I wasn’t using an Arduino, what would I use? Probably nothing. Because the job wouldn’t exist.The Arduino is the Right Tool for Their Jobs Prototypes for a mesh wireless client project. Arduinos inside.
A lot of my work looks like this: the client comes in with an idea but it’s not quite there, and it needs some development before it can become a product. First I build a proof of concept, but then we often move to iterative prototypes where we do a lot of testing and measuring. What is learned from one prototype is rolled into subsequent prototypes in a continuous flow of learning and refinement. (The following saying applies to this process: “Developing hardware is just like developing software, except that every time you hit ‘compile’ it takes weeks and costs thousands of dollars.”)
Eventually, we reach the end of what’s possible with the Arduino and readily available components. Then it’s time for the engineers to design a solution: something focused directly around exactly what was discovered, with minimal waste. That engineered solution is not very likely to include an Arduino.
But until we hand the job off to the engineers, the Arduino was part of the solution. And a big reason for that is the comfort level of the client during this phase of iterative refinement. A lot of clients would throw up their hands at an AVR-ISP or a hex file but they know what an Arduino is. They are often comfortable uploading sketches and making changes to them, or even following a wiring diagram. They probably even prototyped their idea with an Arduino. Using an Arduino allows them to remain hands-on with the development of their idea, even as they outsource some of the work to consultants.The Clients have Changed
Sticking with what the client knows and expects is often the right move but there’s another, deeper reason that an Arduino is even involved in the first place. Without the Arduino and the whole ecosystem of open and accessible hardware and tools that has grown along with it, many of my clients would probably never have even begun to develop their ideas. They certainly would never have gotten to the point of hiring me for my help.Custom ultra-slow speed turntable used to capture high magnification video for Broken Sound by Gary James Joynes
The observation that I was going through a lot of Arduinos also made me realize that my clients had changed. I now work more with artists who are incorporating electronics into their work in ways that weren’t accessible just a few years ago, basement inventors who are taking the plunge to see if their idea will fly, people who need small production runs of 10-100 in a world where “small” often means thousands, and stage magicians who need someone to help them make the next great trick happen. (I hadn’t expected that last one, but you better believe that market exists.)
All of these clients need someone to handle the hard or time-consuming parts of something they otherwise grasp, or someone to make them something they can plug in to the rest of their work. They don’t always have much of a budget to work with, but they do have enthusiasm and they know what they want. They’re idea people who roll up their sleeves and get their hands dirty, and they weren’t around in the numbers that they are now.
There’s one more advantage to working with these types of folks: when people have experience with developing their own solutions and experience running into the roadblocks, they usually also have some understanding of and appreciation for the kind of time, work, detail, and costs that go into development. Those of you who have done professional development work will recognize what a boon that is.
I’ve done custom work for many people over the years, but change is constant. It’s a big world and I’ve only worked in and seen my piece of it. Have you found things to be as I described, or different? Is my experience somehow unique? Post up in the comments!
Filed under: Curated, Featured, Interest, Original Art, slider
At Hackaday we think that hackers have the power to make the world a better place with their builds. This air-powered cheesy-poof rifle is not one of those builds, unless making the world a little more fun and slightly messier makes it a better place.
The principle of [NightHawkInLight]’s design is simple – an electric leaf blower provides the power, and a big vat o’ poofs provides the ammo. Getting the two together and providing a barrel is a matter of some simple plumbing with 1″ PVC pipe and fittings. But wait – lest you think this hack, like the ammo, is just a delicious bit of fluff, there’s something to be learned about fluid dynamics here. With a plain tee fitting, the leaf blower would only pressurize the magazine, making it difficult to chamber a round. But by adding a small restriction to the incoming air flow, the Venturi effect actually sucks ammo into the chamber and down the barrel, to the delight of hungry wildlife for yards around. Science!
There’s plenty of room for improvement to the design – something along the lines of this gas-powered, tube-fed snowball gun would be keen. As it stands, the cheesy-poof gun seems like good, unclean fun.
Thanks to [Matthew Reed] for the cheesy tip.
Filed under: misc hacks, weapons hacks
A few years ago, you could buy an IRIS 9000 Bluetooth speaker. Its claim to fame was that it looked like the “eye” from the HAL 9000 computer on 2001: A Space Oddessy. There’s something seductive about the idea of having a HAL eye answer your queries to Google Now or Siri. The problem is, it still sounds like Google or Siri, not like HAL.
[Badjer1] had the same problem so he decided to build his own eye. His goal wasn’t to interface with his smartphone’s virtual assistant, though. He settled on making it just be an extension cord with USB ports. As you can see in the video below, the build has HAL-style memory units, a key, and can speak phrases from the movie (well, 28 of them, at least). The key is like the one Dave used to deactivate HAL in the movie.
Inside the MDF enclosure is an Arduino and a wave shield that handles the audio playback. The memory cards are acrylic and the key is machined brass. The result is a good looking project.
Filed under: Arduino Hacks, home hacks
There’s a lot of implantable medical technology that is effectively a black box. Insulin pumps monitor blood sugar and deliver insulin, but you can’t exactly plug in a USB cable and download the data. Pacemakers and cardiac defibrillators are the same way. For these patients, data is usually transmitted to a base station, then sent over the Internet to help doctors make decisions. The patient never gets to see this data, but with a little work and a software defined radio, a team on Hackaday.io is cracking the code to listen in on these implanted medical devices.
The team behind ICeeData was assembled at a Health Tech Hackathon held in Latvia last April. One of the team members has an implanted defibrillator keeping her ticker in shape, and brought along her implant’s base station. The implant communicates via 402-405MHz radio, a region of the spectrum that is easily accessible by a cheap RTL-SDR TV Tuner dongle.
Right now the plan is to intercept the communications between the implant and the base station, decode the packets, decipher the protocol, and understand what the data means. It’s a classic reverse engineering task that would be the same for any radio protocol, only with this ones, the transmissions are coming from inside a human.
The HackadayPrize2016 is Sponsored by:
Filed under: Medical hacks, The Hackaday Prize
Taking good technical photos is a whole separate art from other fields of photography like portraiture. For example, [Steve] mentions that he uses “bullseye” composition, or, putting the thing right in the middle. The standard philosophy on this method is that it’s bad and you are bad. For technical photos, it’s perfect.
[Steve] also has some unique toys in his arsenal. Like a toy macro lens from a subscription chemistry kit. He also showed off his foldscope. Sadly, they appear to no longer be for sale, but we sometimes get by with a loupe held in front of the lens. He also uses things standard in our shop. Such as a gridded cutting mat as a backdrop and a cheap three dollar tripod with spring actuated jaws to hold his phone steady.
In the end, [Steve] mostly shows that a little thought goes a long way to producing a photo that doesn’t just show, but communicates an idea in a better way than just words can manage.
Filed under: digital cameras hacks
Lulzbot’s TAZ 6 has been released. Lulzbot’s printers consistently place in the top three of any 3D printing list, and the TAZ 6 will likely be no exception. [James Bruton] was one of the lucky ones who got a review unit, and first looks are promising. The TAZ 6 has the auto bed leveling found in the Lulzbot Mini, and a ‘power tower’ for all the electronics. There are completely unconfirmed rumors (or someone told me and I forgot who) that the power tower will be available separately at some point.
The most impressive circuit we’ve seen this week month year is the dis-integrated 6502. It’s a discrete 6502 CPU, about a square foot in size. It’s slow, but it works. RAM and ROM is easy to make embiggened, which means someone needs to build a dis-integrated 6522 VIA. Who’s game?
[Jeremy Cook] wanted to learn another CAD package, in this case Onshape. Onshape is the ‘first cloud-only CAD package’, which has one huge bonus – you can run it anywhere, on anything – and one huge minus – it’s in the cloud. He designed a bicycle cupholder.
Last week, several thousand Raspberry Pi Zeros shipped out to retailers in the US and UK. For a time, Pi Zeros were in stock in some online stores. Now? Not so much. Where did they all go? eBay, apparently. It’s called arbitrage, and it’s the only risk-free form of investment.
Remember those ‘bed of nails’ toys, that were basically two sheets of plastic, with hundreds of small pins able to make 3D impressions of your face and hands. No, there is no official name for these devices, but here’s a Kickstarter for a very clever application of these toys. You can use them to hold through hole parts while soldering. Brilliant.
You should not pay attention to 3D printers on Kickstarter. Repeat after me: you should not give money to 3D printers on Kickstarter. Here’s a 3D printer on Kickstarter, promising a 3D printer for $74. I own several hats, and will eat one if this ships by next year.
Filed under: Hackaday Columns, Hackaday links
If you paid a visit to France in the 1980s the chances are you’d have been surprised to see a little brown screen and keyboard sitting next to the telephones wherever you went. At the time, it was another reason apart from the food, wine, and super-fast trains to envy our Gallic cousins. This was Minitel, their take on the cutting-edge of online data services of the day.
Minitel stood apart from similar services of the day in most other countries, because of its business model. Unlike the UK’s Prestel or West Germany’s BTX for which you had to spend significant money on a terminal, the French Minitel terminals were free. Thus in the early 1980s everybody in France was busy using videotext while most of the rest of Europe was still excited by chipping bits of flint into arrow heads. Or at least, that’s how it seemed at the time to those of us who didn’t have Minitel.
The Minitel service was finally shuttered in 2012, but the terminals can still be found. [Tony Pigram] bought one, an Alcatel Minitel 1, and made it into something useful by turning it into a USB serial terminal for his Raspberry Pi. Surprisingly the physical interface between the Minitel and the USB port is a relatively simple level shifter, but the configuration of both the Minitel and the Pi was anything but.
The problem was that Minitel terminals were meant to work with Minitel, and [Tony]’s difficulties were increased by his machine being an earlier model without the handy function key to access settings found on later terminals. A lot of research paid dividends though, and he now has what must be one of the most compact and stylish CRT serial terminals available. We can’t help noticing it has a QWERTY keyboard and English menus, it would be interesting to know which non-French market it was made for.
Filed under: classic hacks
Quality wind chimes are not cheap. No matter how much you spend, though, they generally sound the same year after year. If that bothers you, maybe [sensatroniclab] can help. They’ve posted a simple design for a digital wind chime using the Ototo music generator.
The Ototo is reasonably priced and promises to let you make music from anything (well, anything conductive, anyway). Because the Ototo handles all the music production, the only real building part of the project is the wind sensors. The sensors are made with conductive fabric with a marble at the end for weight.
In the video below you can see [Matthew Ward] talk about the device and actually play it like you might a harp. This would be a good school project owing to the simplicity of using the Ototo, although [sensatroniclab] is actually working on accessibility music projects.
One challenge for students would be to make up new kind of sensors. After all, why wind chimes? Why not rain chimes or a hamster-driven instrument?
Filed under: musical hacks
RFID was supposed to revolutionize asset tracking, replacing the barcode everywhere. Or at least that was the prediction once tags got under five cents apiece. They still cost seven to fifteen cents, even in bulk, and the barcode is still sitting pretty. [Chouchang (Jack) Yang] and [Alanson Sample] of Disney Research hope to change that.
Instead of tagging every electronic device, they use whatever electromagnetic emissions the device currently produces when it’s powered up. What’s surprising is not that they can tell an iPhone from a toy lightsaber, but that they can tell the toy lightsabers apart. But apparently there’s enough manufacturing and tolerance differences from piece to piece that they appear unique most of the time.
The paper (PDF) goes through the details and procedure. The coolest bit? The sensor they use is an RTL-SDR unit with the radio-mixer front end removed and replaced with a simple transformer. This lets them feed baseband (tuning from 0 to 28.8 MHz) straight into the DAC ADC and on to the computer which does the heavy math. Sawing off the frontend of a TV tuner is a hack, for those of you out there with empty bingo cards.
If you like statistics, you’ll want to read the paper for details about how they exactly do the classification of objects, but the overview is that they first start by figuring out what type of device they’re “hearing” and then focusing on which particular one it is. The measure that they use ends up being essentially a normalized correlation.
While we’re not sure how well this will scale to thousands of devices, they get remarkably good results (around 95%) for picking one device out of five. The method won’t be robust to overclocking or underclocking of the device’s CPU, so we’re concerned about temperature and battery-voltage effects. But it’s a novel idea, and one that’s ripe for the hacker-rebuild. And for the price of an RTL-SDR, and with no additional per-tag outlay as with an RFID system, it’s pretty neat.
Thanks [Static] for the tip! Via Engadget.
Filed under: wireless hacks
RGB LED cubes are great, but building the cube is only half the battle – they also need to be driven. The larger the cube, the bigger the canvas you have to exercise your performance art, and the more intense the data visualization headache. This project solves the problem by using Unity to drive an RGB LED cube in real-time.
We’re not just talking about driving the LEDs themselves at a low level, but how you what you want to display in each of those 512 pixels.
In the video, you can see [TylerTimoJ]’s demo of an 8x8x8 cube being driven in real-time using the Unity engine. A variety of methods are demonstrated from turning individual LEDs on and off, coloring swaths of the cube as though with a paintbrush, and even having the cube display source image data in real-time (as shown on the left.)
Using Unity3D to drive an 8x8x8 RGB cube shows results, but does require a computer to do the heavy lifting. In the past we have seen some beautiful animations from RGB cubes, for example from this LED cube driven by an Arduino MEGA, but they don’t have the flexibility this method offers.
The cube itself is what you would expect. At the end of his project explanation video, [TylerTimoJ] walks through the hardware, which is a multiplexed system. Each layer has common anodes, with the cathodes extending downward to the base. 192 connections are drive by an Arduino which is receiving the Unity stream over USB.
You probably recognize [TylerTimoJ’s] username. We just covered another amazing project he’s been working on: a scratch-built solenoid radial engine that is simply exquisite.
Thanks to [supershwa] for the tip!
Filed under: led hacks
[Tim Trzepacz] is working on a pretty cool MIDI controller project over on Hackaday.io. It involves, naturally, a bunch of knobs and buttons. And it’s one of these nice arcade-style buttons that broke when he slammed on his car brakes and it went flying.
He tried gluing the plastic bits back together, but we all know how that works — temporarily. Next, he thought that maybe he could 3D-print a model of the arcade button’s housing. Besides being a lot of work, [Tim] didn’t have a reliable printer on hand. But he did have filament and a soldering iron.
The rest of the story is a slightly ugly mess, but it looks like it’ll work. (And it’s on the inside of the case, after all.) A working part is a good part.
The irony here is that the original choice of 3 mm ABS filament as a printing material is that it’s cheap and available because it’s commonly used in plastic welding. And there are more elegant ways to melt the plastic than with a soldering iron. And more ways to get it melted than direct heating, like ultrasonic welding and friction welding, for instance.
But we still like to see the occasional quickly hacked together effort, at least one per day. What’s your craziest plastic welding success or failure?
Filed under: 3d Printer hacks
Electrospinning is a fascinating process where a high voltage potential is applied between a conductive emitter nozzle and a collector screen. A polymer solution is then slowly dispensed from the nozzle. The repulsion of negative charges in the solution forces fine fibers emanate from the liquid. Those fibers are then rapidly accelerated towards the collector screen by the electric field while being stretched and thinned down to a few hundred nanometers in diameter. The large surface area of the fine fibers lets them dry during their flight towards the collector screen, where they build up to a fine, fabric-like material. We’ve noticed that electrospinning is hoped to enable fully automated manufacturing of wearable textiles in the future.
[Douglas Miller] already has experience cooking up small batches of microscopic fibers. He’s already made carbon nanotubes in his microwave. The next step is turning those nanotubes into materials and fabrics in a low-cost, open source electrospinning machine, his entry for the Hackaday Prize.
As always in fundamental research projects, a whole lot of parameters have to be tuned just right. To speed up the process of finding suitable values for the electric potential, dosing feed rate, emitter to collector plate distance, temperature, and humidity, [Douglas] build his machine with a CNC controlled vertical axis and syringe pump, that can dispense even the smallest amounts of a given solutions accurately. Temperature and humidity control will be added as the project progresses. A host software and GUI allows for easy control of all parameters and will also save and recall presets for different spinning solutions once everything has been dialed in. [Douglas] already ran a few tests, spraying saline solution from an old 3D printer nozzle, and we can soon expect first tests with polymer solutions from the better-suited syringe nozzles he installed.Electrospun fabric, image source
To keep the build affordable and easy to reproduce for other makers, [Douglas] uses available materials and came up with a few design tricks that could also be applied to other projects. The belt-driven vertical axis is based on PVC pipes, on which a 3D-printed bushing block slides up and down, adjusting the distance between the nozzle and the collector plate. An acrylic door with a safety switch prevents the polymer spray from escaping from the spinning chamber. In the heart of the machine sits an Arduino Uno with a gShield, controlling the stepper motors and talking to the host computer. The 3D-printed syringe pump, a custom design, swings out from the side of the machine to allow for easy refilling. Submerged in mineral oil, which may have been chosen to reduce the risk of overheating and arcing, lies a half-wave series voltage multiplier, cranking up the voltage from an AC power supply to a maximum of 30 kV DC.The HackadayPrize2016 is Sponsored by:
Filed under: hardware, The Hackaday Prize
Flying a drone usually leads to–sooner or later–crashing a drone. If you are lucky, you’ll see where it crashes and it won’t be out of reach. If you aren’t lucky, you’ll know where it is, but it will be too high to easily reach. The worst case is when it just falls out of the sky and you aren’t entirely sure where. [Just4funmedia] faced this problem and decided to use some piezo buzzers and an Arduino to solve it.
Yeah, yeah, we know. You don’t really need an Arduino to do this, although it does make it easy to add some flexibility. You can pick two tones that are easy to hear and turn on the buzzers with a spare channel or sense a loss of signal or power.
The device has its own battery so it will work even if the drone’s power depletes. Apparently, the 9V battery will run the whole thing for over 20 hours. Pulsing the audio would probably push that number even higher. Of course, the downside is the drone has to carry the extra weight, but if you recover an otherwise lost drone, that might be a small price to pay.
Filed under: Arduino Hacks, drone hacks