Sunday, February 23, 2014 - 16:00MobilECG goes open source
After a failed crowdfunding campaign, MobilECG has gone open source. MobilECG is a medical grade 12 lead electrocardiograph. A 12 lead system is quite a bit more complex than some of the ECG systems we have featured in the past. [Péter], the founder and designer of the device attempted to fund it through an Indiegogo campaign. While MobilECG is relatively cheap, medical certifications are not. The campaign didn’t reach its goal of $230,000 USD. [Péter] tried again with a grass-roots donation round at his website. That round also fell short of [Péter's] goal to keep working on the project. Rather than let his hard work go to waste, [Péter] has made the decision to release his hardware and software to the community. The hardware is licensed under CERN OHL v1.2. The software is released under the humorously named WTFPL.
While we’re not ECG experts, the basic hardware design appears to be sound. MobileECG is based around the Texas Instruments ADS1278 octal analog to digital converter. Two AVR microcontrollers are used, an ATTiny24, and an ATUC64. The analog design incorporates such niceties as lead off detection and defibrillator protection. It should be noted that there are some known bugs in the design, [Péter] mentions he can be contacted with questions. The software seems to be in an early state, and would require quite a bit of work to get it to a final design. While we do wish [Péter] had better luck with his campaign, we’re always glad to see designs released into the open source community.
Filed under: Medical hacks
Sunday, February 23, 2014 - 13:00Workbench With Built-In Solder Fume Extractor
There’s nothing quite like getting an eye full of solder fumes, but when it comes to solder fume extraction, the most common solution take up a whole lot of work area. Here’s a very clever solder fume extractor that doesn’t get in the way, and can be perfectly positioned over the acrid brimstone of a soldering station.
The build consists of a cheap bathroom vent fan built into the back of the workbench feeding into a long PVC pipe that blows the exhaust to the floor a few feet away. The fan is controlled by a simple wall switch, but the intake is where this build really shines. It’s a series of hard, flexible plastic segments that allow the intake to be precisely oriented above the work piece, or wherever it’s most convienent to suck solder fumes from.
This solder fume extractor is just a part of a really amazing electronics workbench. A lot of thought went into this workspace, from threaded inserts in the work surface to mount a panavise to an amazingly thoughtful equipment rack for computers, monitors, and other assorted heavy equipment.
via Hacked Gadgets
Filed under: tool hacks
Sunday, February 23, 2014 - 10:00Vintage DACs And A Raspberry Pi
Before the days of iPod docks in every conceivable piece of audio equipment, most devices were actually built very well. Most shelf top equipment usually came with well designed circuits using quality components, and late 90s CD players were no exception. [Mariosis] heard of some very nice DACs found in some of these units and decided to take one out for a spin. He’s using a Raspberry Pi to play audio with the DAC found in a late 90s Kenwood CD player.
After fortune favored a CD player with a dead drive on [Mariosis]‘ workbench, he dug up the service manual and found some interesting chips – a PCM56 DAC, a little bit of logic, and an SM5807 oversampling chip that does all the conversion for the DAC.
This oversampling chip uses an I2S – not I2C – bus to carry the data from the CD to the DAC. There is, of course, an I2S driver for the Raspi, but the first attempts at playing audio didn’t result in anything. It turned out there was a problem with what the oversampler expected – the ‘standard’ I2S signal delays the data one tick behind the LRCLK signal.
There are two ways to fix this problem: programming a kernel driver, or building some custom logic to fix the problem. Obviously breaking out some flip-flops and NOR gates was the cooler option, giving [Mariosis] a great sounding stereo with a vintage DAC.
Sunday, February 23, 2014 - 07:00[Dino] Brings the Waterproof Fire
For many of our parents, grandparents, and great grandparents, the things we consider hacking, making, and doing weren’t just for fun. They were important skills that could help one survive. This week [Dino] shows us something his dad taught him: waterproof fire starters. The trick is paraffin wax. [Dino] starts by melting down some wax in a pot. He then dips strips of newspaper in the liquid wax. Several strike anywhere matches also get the wax treatment, are then placed on the newspaper. The newspaper and matches are rolled up into a tight bundle, which is itself dipped in wax several times.
The resulting small bundle of waxed newspaper and matches is safe and easy to carry in pocket or backpack. It also becomes the perfect wet fire starter. The “newspaper shell” is torn off into strips of waxed paper, which burns slowly and allows the tinder and wood to catch. [Dino] demonstrates his pioneering skills by starting a fire at the end of the video. When the inevitable zombie apocalypse hits, we definitely want [Dino] at the Hackaday compound.
Filed under: classic hacks
Sunday, February 23, 2014 - 04:01Remote Controlled Lawn Mower Lets you Sit Back and Enjoy The Show
“Its hard to find people that actually WANT to mow their lawn.” A more true statement has never been made. [Kurt's] project turns an old lawn mower into a remote control lawn mower.
The first step of this build is to replace the front drive wheels with mini-bike tires which have built-in gear tooth sprockets. The rear wheels were then replaced with large caster wheels. The 12-24V DC motors and gear boxes used come from National Power Chair. While we have seen more complicated RC lawn mowers before, this project is a great way to get started. All that [Kurt] wanted was to make lawn mowing more fun, we believe that he has succeeded. This thing is very mobile and can turn on a dime. Check out the demo video after the break.
What’s next? Add a GPS, a Raspberry Pi, and a few other odds and ends. Tie it together with some clever programming and you will have your own autonomous lawn mower. Have you already created a completely autonomous lawn mower? Let us know!
Filed under: wireless hacks
Sunday, February 23, 2014 - 01:01Breadboardable WS2812 LEDs
Hackaday sees a ton of projects featuring the WS2812 series of digitally controllable RGB LEDs, in the form of bare chips, RGB LED strips, or some form of Adafruit’s NeoPixels. All these WS2812 LED products have one thing in common – they’re chip LEDs, making some projects difficult to realize. Now there’s a new member of the WS2812 family – a through-hole LED version - that should be available through the usual sources sometime later this year.
The key difference between these and the usual WS2812 LEDs is the packaging; these are 8mm LEDs with pins for power, ground, data in, and data out. With the preexisting libraries, this 8mm LED should work just the same as any other WS2812 LED.
Aside from a through-hole package, these new LEDs are very diffuse and aren’t as blinding as the normal chip LEDs. If you want to pick up a few of these LEDs, they’re available here, 13 LEDs for $15. There’s a lot of potential here for RGB LED cubes, something we hope to see sooner rather than later.
Saturday, February 22, 2014 - 22:00DIY Ceiling Rack Keeps your Bikes Out of the Way
Need to optimize some space in your garage? Why not build a ceiling mounted winch-assisted bicycle rack!
[Mathieu] already has a rather spacious garage, but wanted to make it even more organized. He built the bicycle rack out of 1″ square aluminum tubing, and it’s all bolted together (no welding required!). The bikes sit in aluminum U-channels to be secured in place. The entire rack is hinged off of the back wall, and a pulley system using a little ATV winch raises and lowers the rack for easy access to the bikes.
It’s currently powered off a 12V motorcycle battery, which he plans to add a trickle charger to — that being said, it has lasted for more than 6 months and he still hasn’t had to recharge it! He threw together a little control circuit featuring two relays (up and down) and a 2 channel remote control. The motor is a little slow, but it does the job quite well. If he wanted to get it going a bit faster, he could probably double the voltage to allow for a quicker movement — since it’s only on for short periods of time it should be okay. Seeing hacks like this has us wondering just how many winch-driven extras you could build into a single abode.
Check out the following video of it in action!
Filed under: transportation hacks
Saturday, February 22, 2014 - 19:01A Cheap Honeycomb Table Replacement for your Laser
CO2 lasers make use of a honeycomb table which allows you to support parts you are cutting — without cutting into the bed too much. Unfortunately they are a consumable part, so they will eventually wear out, and they aren’t that cheap. [Claptrap] came up with an excellent alternative.
A few months ago, his radiator blew in his station wagon, and it had to be replaced. He was about to throw it out when he realized the similarity of the radiators cooling fins, to that of his honeycomb table… He cut it down to size, pressure washed it (though he notes you should probably wash it first before cutting) and put it in place. It works great!
The only caveat we have is that you should probably flush the radiator with a water pump first — you don’t want to be heating up any residual radiator fluid inside the radiator channels!
Saturday, February 22, 2014 - 16:00FLUX 1440: A Highly Impractical but Awesome Clock
One our tipsters just sent us this great project — it’s a unique style of clock that we haven’t seen before. It was completed as part of what we think was a post-graduate program by [Felix Vorreiter]. This is FLUX 1440 (translated).
It uses 1200 meters of marked rope that is fed into the clock and strung between various pulleys and gears. Every second, the rope is moved 1.3cm. Every 57 seconds, the time is readable across the strands of rope — but only for 3 seconds. After that everything goes “back into the river”, a metaphor for chaos.
The explanation behind it is in German, but we’ve tried to piece together a general statement about the meaning behind it. Of course, we’d love if one of our German readers could provide a better translation!
FLUX 1440 displays time as a spatial dimension and counts the length of a day using a long segmented rope. The length of each minute is felt physically, as the viewer must wait as the shapes change until the current time reveals itself from the chaos of the markings.
Stick around for an extremely well produced video demonstrating it — it’s also in German, but we think you’ll be able to piece together the meaning.
Filed under: clock hacks
Saturday, February 22, 2014 - 13:01Listening to a Smart Scale
[Saulius] couldn’t find a cost-effective wireless scale that did what he wanted, so he reverse engineered the communication protocol for an off the shelf model to get weight data himself.
[Saulius] bought a cheap Maxim 29-66SH scale that uses infra-red to communicate to a detachable digital readout. Using the USB IR toy, [Saulius] intercepted the messages that were broadcast. After a little reverse engineering and with the help of some Python scripts, he soon discovered the protocol his scale was using to encode weight messages.
Since all the communication is through IR, there is no need to do any invasion of the scale as the receiver can be placed anywhere in line of sight from the transmitter on the scale itself.
Check out the demo video for the whole thing in action. If patching into the scale isn’t hard enough, you should just build one from scratch.
Filed under: home hacks
Saturday, February 22, 2014 - 10:01Smart Reflow Oven is Over-Engineered
[Linas] reverse engineered an AMOLED HTC 800×480 screen and interfaced it with an STM32 micro-controller, along with some other components, to make a gorgeously over engineered reflow oven.
Under the hood there is a PSoC5LP PID controller to control the 800W IR heating coil and two K-type thermocouples for sensing.
The real beauty is in the relatively small STM32 chip powering the HTC AMOLED screen. The AMOLED screen is high contrast and has a wide viewing angle, giving it a clear crisp view from all front facing viewpoints. Though pushing the limits of what the STM32F429i can do, [Linas] managed to make a very nice “home-grown” user interface, complete with user configurable settings and current temperature graphs.
The user interface looks very responsive and using some clever programming, [Linas] was able to make use of the potential of the screen to provide beautiful plots and interface widgets.
[Linas] goes into quite a bit of detail about the programming involved with rendering to the screen, so be sure to check out the video after the jump.
Saturday, February 22, 2014 - 07:00Researchers Create Synthetic Muscle 100 Times Stronger Than the Real Thing
A team of researchers at the University of Texas at Dallas have come up with an ingenious way to make a low-cost, high strength, artificial muscle. Their secret? Fishing line. The study was just published today in the journal Science, and the best part is they describe how to recreate it at home.
To create it, the researchers take regular fishing line (polyethylene or nylon string) and twist it under tension until it curls up into a tightly formed spring. It can then be temperature treated to lock in this position.
When heated again, the plastic tries to untwist — the peculiar thing is, this causes the entire coil to compress — think of it as Chinese finger-trap. Polyethylene and nylon molecules also contract lengthwise when heated. It can contract up to about 49%, with as much pulling power as 100 times its equivalent human muscle in weight. This equates to about 5.3 kilowatts of mechanical work per kilogram of muscle weight — similar to the output of a jet engine.
Stick around to see the video of how to make it — we’re excited to see what you guys think up for project applications!
[via Popular Mechanics]
Filed under: chemistry hacks
Saturday, February 22, 2014 - 04:00Dual Color Extruder With A Single Stepper
Once you have a 3D printer able to build a few objects in a single color, the next logical upgrade is a dual extruder. A dual extruder allows for multiple color prints, and by adding a dissolvable filament, the ability to print object that would otherwise be impossible. Fitting a dual extruder on an existing 3D printer presents a problem: simply by using a second stepper motor, you reduce the print area of your printer significantly. That’s the problem Dglass 3D aims to solve with their extruder. It’s a dual filament extruder that uses only one stepper motor and takes up less space than some other single filament extruders.
This isn’t the first time the guys at Dglass 3D have tried Kickstarting a dual filament extruder; last year we saw a very similar mechanism that used a single stepper motor to feed two filaments. This older model lacked retraction, though, meaning two colored prints would range somewhere between messy, inaccurate, to impossible.
The new extruder uses a servo to ‘latch’ the filament and drive it into the hot end. This means retraction of the filament is possible and from the sample prints with this extruder, the results look pretty good.
Below You’ll see a few video demos of the dual color/retraction extruder printing an object in black and white filaments at the same time. It’s very cool, and with the addition of a dissolvable filament means very complex objects can be printed very easily.
Saturday, February 22, 2014 - 01:00Meltinator 9000 Fuses Glass by Degrees
[Richard]‘s wife scored an Evenheat glass-fusing kiln, but the 20-year-old temperature controller was broken. He could have simply ordered a replacement controller, but that kind of problem solving doesn’t get you on Hack a Day. His wife wanted more control over the kiln and he convinced her that building their own was the way to go. Thus, the Meltinator 9000 was born.
[Richard]‘s design uses an Arduino Uno and an Adafruit display shield, protoshield, and thermocouple reader board. He built a simple relay driver with a resistor, BJT, and a diode and connected it to pin 13 and its built-in indicator. To [Richard]‘s delight, all of this fit in the original enclosure.
[Richard]‘s software provides 25 fusing schedules with ten steps apiece. Each step has a target temperature, rate of temperature change, and a hold time which can be increased on the fly. He ran a test program that heated the kiln to 1500°F at a rate of 2550°F/hour. He then cooled it to 500°F at a rate of 1000°F/hour, which took longer than he thought. The good news is that the kiln is well-insulated! [Richard] has the software available on his GitHub.
Don’t have a glass kiln? Prefer to control beer-related temperatures? You could always hack your stove in the name of homebrewing.
Filed under: Arduino Hacks
Friday, February 21, 2014 - 22:00Hacking the Linksys WRT120N Part 2
[Craig Heffner] has been busy with his Linksys WRT120N router. When we last checked in on [Craig] he had reverse engineered the obfuscation techniques used in the router’s firmware. Since then, he’s re-enabled JTAG, cracked the “encryption” used for saving configuration backups, and now he’s devised a simple attack to change the admin password. With the firmware unlocked, [Craig] went after the hardware JTAG. His first hurdle was a missing jumper connecting the TDI pin to the processor. With a solder blob making the connection, he then found the router would connect to his JTAG debugger, and immediately reset. TDI had been re-used as a GPIO in software, and assigned to the reset button on the back of the router. [Craig's] JTAG pod was pulling the pin low and causing the reset. To make matters worse, the bootloader also redefined and checked for the reset button. If the button were pressed it would boot into a recovery mode. [Craig] patched the bootloader with a little help from IDA pro. He then desoldered the router’s flash and programmed it outside the system. The firmware required a similar patch. Rather than desolder the flash chip again, [Craig] created a firmware update the router would accept and flashed it via the router’s web interface.
Since he already was deep into the Linksys Firmware, [Craig] looked for any obvious attack vectors. He found a big one in the /cgi/tmUnBlock.cgi. Inside the firmware, the URL sent to the CGI would be sent through sprintf(). In plain english, it means that no input length checking was happening – so a URL longer than the firmware engineers expected (in this case 256 bytes) would overflow into areas of memory it wasn’t supposed to – in this case, the stack. For an astute attacker, that’s a wide open door. [Craig] was able to use find some Return Oriented Programming (ROP) gadgets and created an input value that would cause the router to reset its own administrator password. After running the exploit, a quick trip to the router’s webpage proved his attack was successful.
If that wasn’t enough, [Craig] also spent some time looking at the patches to the router’s firmware. The release notes of one of the patches mentioned encrypting configuration files. The WRT120N, like many routers, allows the owner to download and save the configuration as a file. It turned out that the “encryption” scheme was nothing more than an exclusive OR with 0xFF. A pretty weak encryption scheme by any standards. To [Craig] we send our congratulations. To the WRT120N software engineers, we’d suggest taking one of [Craig's] embedded device exploitation classes.
Filed under: peripherals hacks
Friday, February 21, 2014 - 19:00We’re Going To The Midwest RepRap Fest
One month from now, Goshen, Indiana – deep in the land of Dairy Queens – will become one of the premier sites for RepRapping, 3D printing and everything involving open source manufacturing. It’s the 2nd annual Midwest RepRap Festival to be held March 14-16. Oh, Hackaday will also be there, cavorting around, distributing some swag, and doing some live videos and posts of the event.
Highlights of the Festival include [Prusa] giving a talk on the state of open source printing, [Sonny Monicou] discussing the challenges of his RepRap workshops, a roundtable discussion of the RepRap project, [Nicholas Seward] and his creations – the Wally, Simpson, and Lisa, along with a few folks from Lulzbot and UltiMachine. Basically, the only way to go to a bigger RepRap convention would be to visit a Maker Faire, and even that would only add a few hundred 9-year-olds astounded by printed Minecraft figurines.
If you’re willing to make the drive, there’s no fee to attend; just register, show up, and you’ll get a table for all that up-til-midnight RepRapping. There’s also a waffle breakfast on Sunday, along with me walking around makin’ it rain Hackaday stickers.
Friday, February 21, 2014 - 16:00QFN Breakout Is Easy On the Eyes, Wallet
What do you do when you have ATMega328s in QFN package burning a hole in your bug box, but you aren’t set up for SMD and have limited access to parts? You man up and do what [Djpanjan] did: make your own breakout board with solder, right angle header, and many tiny, beautiful wires.
[Djpanjan] says the process is a simple one that requires great concentration. Once he had it broken out, he covered the wires with hot glue to make sure they all stay in place. He programmed it using an Arduino as an ISP and he was able to run the blink sketch without issue. He blinked all the output pins to make sure there were no shorts.
[Djpanjan] says that if he can’t get a breakout for his LQFP-144, he’s going to make his own again. Good luck, [Djpanjan]. We’re all counting on you.
Filed under: misc hacks
Friday, February 21, 2014 - 13:00DIY Router Base For Your Dremel
Dremel rotary tools are handy. Some of the attachments are convenient. [vreinkymov] felt the convenience wasn’t worth the cost, so he decided to make a Router Base for his Dremel. These types of attachments are used to hold the Dremel perpendicular to the work surface.
Underneath the little nut/cover near the spindle of the Dremel, there is a 3/4″-12 threaded feature used to attach accessories. A quick trip down the hardware store’s plumbing aisle resulted in finding a PVC reducer with the correct female thread to fit the Dremel. Once on the rotary tool, the reducer threads into a PVC nipple that is glued to a piece of acrylic. The acrylic acts as the base of the router attachment.
Dremel’s official router base is called the 565. It slides up and down to adjust the bit height and locks with a thumb screw. [vreinkymov]‘s design utilizes the threads of the reducer and nipple to allow height adjustment. If those threads get a little loose, it would be possible to drill and tap a hole for a thumb screw that would prevent the reducer and nipple from turning in relation to each other.
Those with access to a 3D Printer may be interested in this router attachment hosted on thingiverse.com. The height is not adjustable but otherwise it appears to be pretty nice.
Friday, February 21, 2014 - 10:00This Party Jukebox is Bigger on the Inside
In honor of the recent 50th anniversary of Doctor Who, [David Prouty] decided to build a 1/3rd scale replica of the Tardis. He also decided to give it a few extra features on the inside… Introducing the Recycled Tardis Jukebox!
It was constructed primarily out of recycled cardboard boxes (pizza, FedEx, UHaul, etc) and [David] has done an amazing job painting and detailing it!
Since it’s so big, [David] wanted it to be functional too, so he’s added Bluetooth speakers, sound activated lights, disco balls, and even a fog machine on the inside. It’s all controlled wirelessly by remote, and it’s sure to be a hit at any party he decides to throw.
Stick around for the videos showing it in action — and of course, making our favorite sound VWORRRRRP VWRORRRP VWORRRP!
Filed under: musical hacks
Friday, February 21, 2014 - 07:01Open Bitcoin ATM
If there’s one thing Bitcoins can benefit from, it’s easier accessibility for first-time users. The process can be a bit daunting if you’re new to cryptocurrency, but [mayosmith] is developing an open Bitcoin ATM to help get coins in the hands of the masses. There are already some Bitcoin dispensers out there. The Lamassu is around 5k a pop, and then there’s always the option of low-tech Condom Vending Machine conversions.
[mayosmith's] build is still in the proof-of-concept phase, but has some powerful functionality underway. The box is made from acrylic with a front plate of 12″x12″ aluminum sheet metal, held on by 2 aluminum angles and some bolts. Slots were carved out of the aluminum sheet for the thermal printer and for bill acceptor—the comments identify it as an Apex 7000. Inside is an Arduino with an SD Shield attached. Dollars inserted into the acceptor trigger the Arduino to spit out a previously-generated QR code for some coins via the thermal printer, though all values are pre-determined at the time of creation and stored sequentially on the SD card. Stick around for a quick video below, and check out the official page for more information: http://openbitcoinatm.org