Plans for Hackaday Munich are coming along quite nicely. Today we’re happy to announce that [Sprite_TM] will be speaking at the event. Click that link above and make sure you get your tickets for November 13th. You can do some hands-on hacking at the Embedded Hardware Workshop, hear the talks, find out which of the five finalists will be the grand prize winner, and enjoy The Hackaday Prize Party along with the Hackaday crew.
You may also know [Sprite_TM] as [Jeroen Domburg], one of the judges for The Hackaday Prize. That’s him on the left in the image above (we love a good avatar!). If you follow Hackaday, you should already be thrilled about meeting him and hearing his talk. The last talk we remember reading about was an epic hard drive controller hack. Just last month we saw a well-executed clock radio overhaul from him. While we’re on the topic, his micro-bots were a spectacular project.
[Sprite_TM] has also offered to help out with the reverse engineering workshop. We’re hard at work making sure everything is in place for those afternoon hacking events. As we solidify details we’ll be adding workshop pages (and emailing those already registered for Hackaday Munich) to let everyone know what to expect. We can report that we have shipped [Sprite_TM] a Bus Pirate so that he can be familiar with it. This will be the primary tool provided for this particular workshop.
The entire Hackaday crew is looking forward to it. See you there!
Filed under: Featured, The Hackaday Prize
Good, workable test gear is key to enabling our hobby. In this post we will discuss where to procure it at rock-bottom prices, what to look for, how to fix it, and how to tailor your laboratory practices around gear that may not be reliable.
We are lucky to be living in an era with plentiful high-quality test gear. Since the Second World War, surplus test gear has been in abundance at low costs enabling hobbyists, innovators, and academics to experiment and build great things. If you are willing to think before you measure you can save serious amounts of money and have a professional laboratory in your home.
Where to buy
The obvious answer is eBay, but the deals on test equipment are at the hamfests. Don’t be fooled by the name. Hamfests sell much more than amateur radio equipment. Hamfests are swap meets where hobbyists trade electronics of all kinds. Check out the ARRL hamfest calendar to find the next local one near you! I suggest you arrive early, however. The culture of hamfests tends to favor showing up as soon as the doors open and leaving about two hours before the official end. The early bird gets the worm!
You will have to go to a number of hamfests before you will find everything you need. Patience is key. Just keep going to hamfests and eventually you will find it or something close. If you need it now you can pay more on eBay and equip yourself very quickly.
Of course there is the mother of all hamfests, the Dayton Hamvention. As I’ve heard many times, if you can’t find it at Dayton you don’t need it.
What to look for – brands & eras of quality
If you are looking for a scope then buy a Tektronics brand, any era. Some of the ‘TV Repairman’ scopes are not bad either. I’ve had good luck with my Heath-Zenith from the late ‘80’s. If the scope is not a Tek or an HP then judge the equipment based on cleanliness. If it’s very clean then it’s worth a try; if dirty then buy two and one will likely work!
For everything else, buy Hewlett-Packard whenever possible. In my experience, tube HP signal generators from the ‘50’s and ‘60’s tend to be very reliable. To no surprise, when you pop the covers off one they seem to be built to some very high specification. Some of the more complex gear from the ‘70’s and ‘80’s can be difficult to service, requiring difficult-to-find card extenders and such. I only buy this gear if it’s clean, and I try to get two whenever possible.
Generally speaking, if you must get any particular piece of gear try to buy two to spread your risk. Expect hamfest test gear to work 60-70% of the time.
Fix it or replace it?
Over time your working test gear will break down. You can either replace it or fix it yourself. This is simply a trade of time for cost. More time spent maintaining your gear, the less you will pay out of pocket to procure and keep your lab running. While in graduate school, my policy was to spend no more than 3 hours repairing the equipment, and if I exceeded this time without any tangible progress I would replace it. My current approach is to buy used gear at hamfests and run it until it dies. If it dies I replace it with another used piece of gear. To make up for the gap in time replacing the equipment, all of my gear has overlapping capability so I’m never without the right instrument for the job.
There are groups dedicated to the repair and restoration of Tektronics scopes and probably others for HP gear too.
For some tube gear such as the Heathkit and other lower-end TV and radio repair gear, you can just use the antique radio repair procedures previously discussed – Making old Heathkit and other old gear very repairable for many decades to come.
Think before you measure – some guidelines for using old gear
Trust nothing! When using old test gear of any type you must tailor your measurement procedures so that you are always verifying. When your circuit is not behaving as expected, the first thing you should do is verify power (all voltages and ground), verify cables, verify outputs of test gear, and verify inputs are working on your test gear. Don’t let a loose BNC input connector on your hamfest scope or a bad test cable fool you into thinking that your amplifier is dead. This is a basic trouble shooting skill extended to your measurement setup (many of you may already do this intuitively).
Example – a microwave laboratory
Microwave test gear is not cheap. Starting in high school, I began to procure test gear, anything at first, and slowly upgraded to better, more reliable equipment over time. This laboratory began turning out serious projects culminating in my PhD thesis, which included two Synthetic Aperture Radar rail imaging systems and a near-field phased array. This lab continues to support all of my work both as a hobbyist and professional. As you can see it is supplied with gear from the 50’s, 60’s, 70’s and the newest stuff is from the 80’s.
Prices, based on what I’ve previously bought and observed
The heavier it is the cheaper it is, for example tube RF signal generators in working condition typically fetch <$100.
Good scopes (Tek brand, 50-100 MHz of bandwidth 2 or more channels) range from $50-$200. Higher the bandwidth the more the scope will fetch, although i once bought an old sampling scope with 2.5 GHz of bandwidth for $100.
Function generators can fetch $20-$50.
Good spectrum analyzers, such as ones based on the HP 141T mainframe, run about $400-$1200 in working condition.
HP microwave signal generators go for $300 and up.
Bench supplies, such as lower power HP Harrison types, $20-$50 each.
Good digital Voltmeters, such as Fluke or Simpson 260’s, $20-$50.
We live in a world full of old test gear and all we have to do is think before we measure. Tackle increasingly more complicated array of projects. Don’t wait until you can visit a friend or go into work to measure something. Instead, have in-house capabilities. Visit your local hamfest and build up a professional lab in your basement or garage today!
My cousin, Juliet Hurley, MBA, MSF, MAC for type-editing this post.
Gregory L. Charvat, is the author of Small and Short-Range Radar Systems, co-founder of Hyperfine Research Inc., Butterfly Network Inc. (both of which are 4combinator companies), visiting research scientist at Camera Culture Group Massachusetts Institute of Technology Media Lab, editor of the Gregory L. Charvat Series on Practical Approaches to Electrical Engineering, and guest commentator on CNN, CBS, Sky News, and others. He was a technical staff member at MIT Lincoln Laboratory where his work on through-wall radar won best paper at the 2010 MSS Tri-Services Radar Symposium and is an MIT Office of the Provost 2011 research highlight. He has taught short radar courses at MIT where his Build a Small Radar course was the top-ranked MIT professional education course in 2011 and has become widely adopted by other universities, laboratories, and private organizations. Starting at an Early Age, Greg developed numerous radar systems, rail SAR imaging sensors, phased array radar systems; holds several patents; and has developed many other sensors and radio and audio equipment. He has authored numerous publications and has received press for his work. Greg earned a Ph.D in electrical engineering in 2007, MSEE in 2003, and BSEE in 2002 from Michigan State University, and is a senior member of the IEEE where he served on the steering committee for the 2010, 2013, and 2016 IEEE International Symposium on Phased Array Systems and Technology and chaired the IEEE AP-S Boston Chapter from 2010-2011.
Filed under: Featured, how-to, tool hacks
[Ben] has written all sorts of code and algorithms to filter, sort, and convolute images, and also a few gadgets that were meant to be photographed. One project that hasn’t added a notch to his soldering iron was a camera. The easiest way to go about resolving this problem would be to find some cardboard and duct tape and built a pinhole camera. [Ben] wanted a digital camera. Not any digital camera, but a color digital camera, and didn’t want to deal with pixel arrays or lenses. Impossible, you say? Not when you have a bunch of integral transforms in your tool belt.
[Ben] is only using a single light sensor that outputs RGB values for his camera – no lenses are found anywhere. If, however, you scan a scene multiple times with this sensor, each time blocking a portion of the sensor’s field of view, you could reconstruct a rudimentary, low-resolution image from just a single light sensor. If you scan and rotate this ‘blocking arm’ across the sensor’s field of view, reconstructing the image is called a Radon transform, something [Ben] has used a few times in his studies.
[Ben]‘s camera consists of the Adafruit RGB light sensor, an Arduino, a microSD card, a few servos, and a bunch of printed parts. The servos are used to scan and rotate the ‘blocking arm’ across the sensor for each image. The output of the sensor is saved to the SD card and moved over to the computer for post-processing.
After getting all the pixel data to his laptop, [Ben] plotted the raw data. The first few pictures were of a point source of light – a lamp in his workspace. This resulted in exactly what he expected, a wave-like line on an otherwise blank field. The resulting transformation kinda looked like the reference picture, but for better results, [Ben] turned his camera to more natural scenes. Pointing his single pixel camera out the window resulted in an image that looked like it was taken underwater, through a piece of glass smeared with Vaseline. Still, it worked remarkably well for a single pixel camera. Taking his camera to the great outdoors provided an even better reconstructed scene, due in no small part to the great landscapes [Ben] has access to.
Filed under: Arduino Hacks, digital cameras hacks, Software Development
The Mini Maker Faire in Atlanta was packed with exciting builds and devices, but [Andrew's] Electric Bubblegum Boards stood out from the rest, winning the Editor’s Choice Award. His boards first emerged on Endless Sphere earlier this summer, with the goal of hitting all the usual e-skateboard offerings of speed, range, and weight while dramatically cutting the cost of materials.
At just over 12 pounds, the boards are lightweight and fairly compact, but have enough LiFePO4’s fitted to the bottom to carry a rider 10 miles on a single charge. A Wii Nunchuck controls throttle, cruise control, and a “boost” setting for bursts of speed. The best feature of this e-skateboard, however, is the use of 3D-printed parts. The ABS components not only help facilitate the prototyping process, but also permit a range of customization options. Riders can reprint parts as necessary, or if they want to just change things up.
[Andrew's] board is nearing the 11th hour over at his Kickstarter page, so swing by to see a production video made for potential backers, or stick around after the break for some quick progress and demo videos.
Filed under: 3d Printer hacks, transportation hacks
Here’s a post from the AMSAT-UK high altitude balloon blog. It’s a great story about a balloon cruising at about 12km above the Earth completing its sixth circumnavigation of the planet. That post is from October 4th, and two weeks later the balloon is still going strong. Right now it’s over the Baltic heading into Russia with no sign of stopping or popping any time soon.
The balloon was launched July 12, 2014 from Silverstone, UK. In the 100 days since then, this balloon has covered 144168 kilometers and has crossed its launching longitude six times. Even if this balloon weren’t trapped at high latitudes (including coming within 9 km of the pole), this balloon has still travelled more than three times the equatorial circumference of the Earth.
The balloon was built by [Leo Bodnar] a.k.a. [M0XER] with a self-made plastic foil envelope. The solar-powered payload weighs only 11 grams. It’s an exceptional accomplishment and one that has smashed all the amateur high altitude balloon distance records we can find.
Filed under: misc hacks
[Christopher] has put together a Prank Stun Baton to annoy his friends. It delivers a slight shock to the person on the business end of the device. Oddly, it’s powered solely by static electricity, there is no battery here and the resulting injury is no worse than touching a door knob after scooting your socks around on some shag carpet.
The design is super simple and is effectively just a rudimentary capacitor. The main housing is a PVC pipe that acts as a dielectric in the ‘cap’ system. Two separate pieces of tin foil are wrapped around the inside and outside of the PVC pipe. These layers of tin foil provide a conductive path up to the a couple of screws stuck in the end of the baton. A ping-pong ball and some foam act as an insulator between the PVC and the screws.
To charge the baton it only has to be brought close to a source of static electricity, a tube TV will do the trick. Rubbing it with a piece of wool will also work. When this is done an electrostatic field is stored in the PVC between the two pieces of tin foil, one side takes on a positive charge and the other a negative charge creating an electric potential between the two screws at the end of the baton. When something (with a low-enough resistance) shorts the screws, the stored energy on the positive screw tries to go to the negative screw, shocking the unsuspecting victim.
Need something a little more powerful? You may want to check out this other stun baton.
Filed under: weapons hacks
Introducing the Hayes Smartmodem 1200. The era of the single station microcomputer…. is over. The Hayes Smartmodem offers advanced features like auto answer and auto dial. Now if we could only find an ‘RS-232 Computer.’
Have a 3D printer and an old router? How about controlling your printer with Octoprint? For some cases, it might be better than using a Raspberry Pi and OctoPi, but you won’t get a camera for streaming pics of your builds to the web.
Last year, [CNLohr] built a microscope slide Minecraft thing and in the process created the smallest Minecraft server ever. The record has now been bested with the Intel Edison. There’s a bit of work to install Java, but the performance is pretty good for one player. Bonus: Minecraft is a single threaded app, so you have another core for garbage collection.
Remember the Scribble pen, that showed just how gullible people are and how crappy tech journalism is? They’re back with a beta program. A mere $15 guarantees you a scribble pen for their beta program. I wouldn’t give these guys $15 of someone else’s money, but lucky for us [ch00f] bit the bullet. He’ll be updating everyone on the status of his fifteen dollars, I’m sure.
Hey, guess what will eventually be in the Hackaday store? Keycaps for your mechanical keyboard. Yes, we actually figured out a way to do this that makes sense and won’t lose money. Pick your favorite, or suggest new ones in the comments:
Filed under: Hackaday links
If you’ve ever had to repair an iPhone for a friend, you’ll know they have a ridiculous number of screws. Most companies standardize screws in their products, but since Apple doesn’t expect you to fix a phone yourself… they may have let this one slide.
You see, each of these screws is different. The red ones are 1.7mm long, the yellow one, 1.3mm, and the orange one, 1.2mm.
Guess what happens if you install either red or yellow screws into the orange spot, since your eyesight isn’t good enough to notice a 0.1mm difference? The screw will cut into the PCB and break several 50 micron traces, as shown in the picture above, causing a blue screen error on the phone.
[Sam Schmidt] is the owner of a repair outfit called iRepairNational, and he and his team spent a day trying to figure out the problem – it’s not exactly easy to spot. They’ve managed to repair it by cutting thin strips of copper foil (the width of a human hair) and floating it into place using the surface tension of the flux they were using for soldering. On average it takes them around 2 hours to do the repair, though they’ve done a few in just under an hour.
Since discovering and sharing the problem, they’ve had customers around the world sending in phones for repair – often at the fault of someone else trying to repair something completely different in the phone, and then using the wrong screw as they put it all back together.
Filed under: Cellphone Hacks, iphone hacks
[jjshortcut] has created an easy to make robot arm that has 6 degrees of freedom. There is not much to it, the frame is made out of 4mm thick hardboard, hobby servos provide the power and a handful of hardware holds it together. The frame has been successfully cut out on both a laser cutter and a cnc router, making this design even more obtainable for any aspiring roboticist.
To control the robot arms movements [jjshortcut] plans to use a standard Arduino. There are certainly plenty of servo motor shields available but he still decided to design his own. In addition to the standard motor power and servo connections, a header for an infrared receiver was added for potential future communication options.
Like any project, there were some hiccups along the way. First, several revisions of the gripper were necessary to get the correct tooth profile that resulted in smooth and tight movement. Also, while making the shield the spacing between banks of headers came out one header too close! On this first board [jjshortcut] just bent the pins so they would fit into the Arduino. You can’t let some minor snafu prevent forward momentum of a project!
[jjshortcut] has done the hard part; the design. He has made all his mechanical and electronic files available… so go and build one! Check out the video after the break.
Filed under: robots hacks
A while back [Dave] decided he wanted to build his own keyboard. [Dave] has no experience in design, or dealing with manufacturing companies, or even sourcing materials – he just wanted to see if he could do it.
That’s the beauty of the DIY world – most of the time, you can do it, you just don’t know it yet. The keyboard is made out of laser cut steel and acrylic sheets. The switches and key caps are Cherry MX Browns, supplied by GONSKeyboards Works. A Teensy 2.0 lies at the heart of the keyboard acting as an HID device, and the whole thing assembled looks pretty slick – but it wasn’t easy getting to that point.
As [Dave] explains in his article, designing the enclosure from scratch was the hardest part. Seriously, how would you design a keyboard? Do you look at the keyboard you already have? He started researching different DIY keyboards and stumbled upon [Matt3o's] Brown Fox Keyboard – a simple yet elegant design that he would take a few design cues from. He then learned how to use DraftSight (Free 2D CAD software from the people who make SolidWorks). He admits the learning curve is pretty steep; if you’ve never used CAD before.
Once he had it all figured out he was able to sketch up the layout, but when he tried sending it off to the manufacturer, they wanted a completely dimensioned drawing – you know, instead of just taking the CAD flat pattern and putting it into the CNC machine…
[Dave] admits “If anyone here is a Draftsman, I apologize for this filth.” However, the company was able to use it! So if it works it works – though they probably used the flat pattern and just had the drawing for reference. But to be fair, working as a mechanical developer, I’ve seen worse drawings. Much worse.
But for [Dave's] reference, and any other designers in training, it could be cleaned up considerably just by dropping a few decimal places, as some manufacturers would see over three zeros as an indication that it has to be accurate down to the micron… which would be incredibly expensive. Oh and keeping the dimensions off of the actual part using leader lines (extended dimension lines) also keeps the drawing neat and tidy. That’s just Drafting 101 – I am by no means an expert.
Anyway, back to the hack. Lucky for [Dave], everything fit perfectly when he put it altogether, saving him from having to modify the design. All that was left was the tedious task of wiring up all the switches to the diodes and then to the Teensy, whose small size is normally a blessing, but in this case becomes very fun to wire.
He’s also done a great job explaining the entire process, which is invaluable to anyone interested in jumping into the design world, and for [Dave] this is just the beginning. He’s already planning version 2.0 which will feature his own PCB!
Filed under: computer hacks
Last May brought the unastonishing news that companies were taking the Systems on Chip found in $20 wireless routers and making dev boards out of them. The first of these is the VoCore, an Indiegogo campaign for a 360MHz CPU with 8MB of Flash and 32MB or RAM packaged in a square inch PCB for the Internet of Things. Now that the Indiegogo rewards are heading out to workbenches the world over, it was only a matter of time before someone got Doom to run on one of them.
After fixing some design flaws in the first run of VoCores, [Pyrofer] did the usual things you would do with a tiny system running Linux – webcams for streaming video, USB sound cards to play internet radio, and the normal stuff OpenWrt does.
His curiosity satiated, [Pyrofer] turned to more esoteric builds. WIth a color LCD from Sparkfun, he got an NES emulator running. This is all through hardware SPI, mind you. Simple 2D graphics are cool enough, but the standard graphical test for all low powered computers is, of course, Doom.
The game runs, but just barely. Still, [Pyrofer] is happy with the VoCore and with a little more work with the SPI and bringing a framebuffer to his tiny system, he might have a neat portable Doom machine on his hands.
Filed under: classic hacks, linux hacks
Vacuum Forming is a process used to mold plastic into a desired shape. A thin sheet of plastic is heated to a soft state and then air pressure is used to press the plastic down around or into a mold. Vacuum forming can be used to make a variety of items, anything from product packaging to bath tubs.
That being said, a vacuum former is probably one of those things that would be nice to have around but may not get a lot of use. Therefore, spending any significant amount of money on one would result in a low-value situation. For some folks, building one from scratch may be the way to go. [Amalgamized] built his own low-cost vacuum former and did a great job documenting the build.
There is a two-pronged attack to keep the costs down on this project. First, the frame is made from readily available materials that you probably have kicking around in your wood scrap bin. The sides of the frame are 3/4″ plywood and the hole-filled top is made from 1/4″ MDF. A piece of PVC pipe connects the chamber below the top piece of MDF to a shopvac. The shopvac pulls the air down through the top’s holes; think reverse air hockey table.
Attack prong #2 is that there is no dedicated heater. Binder clips secure the plastic sheets to an aluminum window frame which are then put in the oven for a few minutes between 250 and 300ºF. When the plastic starts to droop, it is quickly removed from the oven and placed over a mold. The shopvac creates a low pressure zone under the plastic and atmospheric pressure pushes the plastic down around the mold.
Filed under: tool hacks
[Raphael] has a motorcycle he’s constantly working on, and for him that means replacing the battery occasionally. Tired of the lead-acid batteries that have been used for 100 years now, he took a look at some of the alternatives, namely lithium and the much cooler supercapacitor option. A trip to the local electronics distributor, and [Raphael] had a new supercapacitor battery for his bike, and hopefully he’ll never need to buy another chunk of lead again.
The battery pack is built from six 2.7V, 350F caps, a few connectors, and a handful of diodes. These are lashed together with rubber bands to form a 16V, 58F capacitor that makes for a great stand-in for a chunk of lead or a potentially puffy lithium battery.
[Raphael] put up a walkthrough video of his battery pack where he shows off the enclosure – an old, empty lead acid cell. He also goes through the back current protection and his method of balancing the supercaps with a few diodes.
Filed under: transportation hacks
[jimmayhugh] is a homebrewer and has multiple fermentation chambers and storage coolers scattered around his home. Lucky him. Nevertheless, multiple ways of making and storing beer requires some way to tell the temperature of his coolers and fermenters. There aren’t many temperature controllers that will monitor more than two digital thermometers or thermocouples, so he came up with his own. It’s called TeensyNet, and it’s able to monitor and control up to 36 1-wire devices and ties everything into his home network.
Everything in this system uses the 1-Wire protocol, a bus designed by Dallas Semiconductor that can connect devices with only two wires; data and ground. (To be a fly on the wall during that marketing meeting…) [jimmay] is using temperature sensors, digital switches, thermocouples, and even a graphic LCD with his 1-wire system, with everything controlled by a Teensy 3.1 and Ethernet module to push everything up to his network.
With everything connected to the network, [jimmay] can get on his personal TeensyNet webpage and check out the status of all the devices connected to any of his network controllers. This is something the engineers at Dallas probably never dreamed of, and it’s an interesting look at what the future of Home Automation will be, if not for a network connected relay.
Filed under: Microcontrollers
There are quite a few flavors of line following robot. No matter how they’re made, most are built for speed and accuracy. The Cambot by [Jorge Fernandez] however makes use of a traditional video camera to read visual input instead of the reflective sensors we’re used to seeing in these types of robots. Because of this it lacks those swift and agile qualities, but scores points with its unique analog design, over-sized tricycle wheels, and stylish RCA jacks poking out on the side.
Coupled with a PIC 16F84A microcontroller, [Fernandez] divides the video input from the camera into 625 lines. The PIC is responsible for scanning horizontally across these lines and translating the proportions of black and white into PWM pulses. The duration these proportions are seen by the camera determines the PWM frequency fed to the left and right servo motors driving the robot.
As far as line-followers go, this is a refreshing retro approach to the concept. [Hernandez] outlines the finesse about driving his cambot on his blog (an English translation can be read here) and provides a complete schematic for those who are interested in whipping up their own quirky little machine.
Filed under: Microcontrollers
The Intel Edison is an incredibly small and cheap x86 computing platform, and with that comes the obvious applications for robotics and wearable computing. [mz] had another idea: what if the Edison could do work that is usually done by workstations? Would it make economic sense to buy a handful of Edisons over a single quad-core Xeon system?
[mz] thought the Edison would be an ideal platform for fuzz testing, or sending random, automated data at a program or system to figure out if they’ll misbehave in interesting ways. After figuring out where to solder power and ground wires to boot an Edison without a breakout board, [mz] got to work benchmarking his fuzz testing setup.
Comparing the benchmarks of a fuzzing job running on the Edison and a few servers and workstations, calculations of cost-efficiency worked out well for this tiny x86 system on module. For parallelizable tasks, the Edison is about 8x less powerful than a reasonably modern server, but it’s also about 5-8x cheaper than a comparable desktop machine. Although renting a server is by far the more economic solution for getting a lot of computing power easily, there are a few use cases where a cluster of Edisons in your pocket would make sense.
Filed under: computer hacks
Trick question! Of course you do, everyone loves Comic Sans! It’s only like the best font in the history of the internet! Why would you ever use anything else?
Oh! Is it because you feel like writing your novella on a computer is cheating? You wish you could use Comic Sans on your classic Sears-branded Brother Charger 11 typewriter from the 70’s? Don’t worry, we’ve got you covered.
Jokes aside, this is actually a pretty clever hack. He’s modified a typewriter to use custom letters which he has laser cut out of acrylic and super glued to the strikers of the typewriter.
He calls it the Sincerity Machine.
It’s my wish that a classic, functioning typewriter altered to write in the most popularly despised font of modern times will provoke thoughts about such media concerns.
In addition to modifying the strikers, he’s also made new key covers with a vinyl cutter with their respective, and delightful fonts for all to see.
Filed under: laser hacks, tool hacks
Good morning, Mr. Hunt. Your mission, should you choose to accept it… blah blah blah… This post will self-destruct in five seconds.
This is [Diego Trujillo Pisanty's] latest project dubbed “This Tape Will Self-Destruct“, and it’s a fully functional small scale printer, whose media catches on fire immediately after printing. Beyond the obvious Mission Impossible connection, you could also think of it as real-life snapchat — just throw a webcam on there and some faxing capabilities…
Apparently [Diego] was inspired to build this machine after the BBC reported that a Kremlin security agency was upgrading the office with typewriters in attempt to reduce privacy leaks from computer hardware, in fear of WikiLeaks and [Edward Snowden].
It is an art piece (the horror!) but is actually quite the piece of hardware. So unfortunately, like most art pieces, the artist doesn’t give much detail on how it works, because that would ruin the illusion of the project… or something. Still, it’s an amusing project. Video below.
Filed under: security hacks
In the early days of film, there was a time when French 3D Cinema was called “Relief Cinema”. The word, Relief, however brings the idea of something physical to mind when we hear it, which is why the name was later tweaked to include the more intangible term, 3D. Playing on this fact, French Artist [Julien Maire] has designed and built an over-sized projector for his installation titled “Relief“, that creates an animation by passing light through a series of individual 3D vignettes.
[Julien’s] intricately built projection reel in itself is an impressive mechanical feat, arguably out-staging the image it exists to produce on the wall of the gallery space. The eighty-five individual frames that create the short clip of a man digging a hole in the ground, consist of small figurines made with a stereo lithography printer. The semi-transparent nature of the resin used by the SLA printer gives the shadow cast by the projector a series of foggy-values that create a three dimensional appearance instead of merely casting a silhouette of the shape. This installation blends new and old technologies together to produce something we’re familiar with, but leaves us admiring an object that we’ve never seen before.
[Julien’s] “Relief” is currently being exhibited at iMAL (interactive Media Art Laboratory in Brussels) which will run throughout the month of October. If you happen to find yourself on a long stay in Europe before the Hardware Workshop in Munich, you could make a pitstop and check it out!
Filed under: misc hacks
[Darell] recently purchased a fancy new bathroom scale. Unlike an average bathroom scale, this one came with a wireless digital display. The user stands on the scale and the base unit transmits the weight measurement to the display using infrared signals. The idea is that you can place the display in front of your face instead of having to look down at your feet. [Darell] realized that his experience with infrared communication would likely enable him to hack this bathroom scale to automatically track his weight to a spreadsheet stored online.
[Darell] started by hooking up a 38khz infrared receiver unit to a logic analyzer. Then he recorded the one-way communication from the scale to the display. His experience told him that the scale was likely using pulse distance coding to encode the data. The scale would start each bit with a 500ms pulse. Then it would follow-up with either another 500ms pulse, or a 1000ms pulse. Each combination represented either a 1 or a 0. The problem was, [Darell] didn’t know which was which. He also wasn’t sure in which order the bits were being transmitted. He modified a software plugin for his logic analyzer to display 1’s and 0’s on top of the waveform. He then made several configurable options so he could try the various representations of the data.
Next it was time to generate some known data. He put increasing amounts of weight on the scale and recorded the resulting data along with the actual reading on the display. Then he tried various combinations of display settings until he got what appeared to be hexadecimal numbers increasing in size. Then by comparing values, he was able to determine what each of the five bytes represented. He was even able to reconstruct the checksum function used to generate the checksum byte.
Finally, [Darell] used a Raspberry Pi to hook the scale up to the cloud. He wrote a Python script to monitor an infrared receiver for the appropriate data. The script also verifies the checksum to ensure the data is not corrupted. [Darell] added a small LED light to indicate when the reading has been saved to the Google Docs spreadsheet, so he can be sure his weight is being recorded properly.
Filed under: Raspberry Pi