The Network Of 1-Wire Devices

October 18, 2014 by Brian Benchoff 13 Comments

teensynet

[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.

This Analog Cambot Plays Outside The Lines

October 18, 2014 by Sarah Petkus 12 Comments

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.

Continue reading “This Analog Cambot Plays Outside The Lines” →

The Economics Of Fuzz Testing With The Intel Edison

October 18, 2014 by Brian Benchoff 16 Comments

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.

Don’t You Just Love Comic Sans?

October 18, 2014 by James Hobson 29 Comments

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. Continue reading “Don’t You Just Love Comic Sans?” →

Mission Impossible Self Destructing Messages

This Message Will Self-Destruct In 5 Seconds

October 18, 2014 by James Hobson 22 Comments

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.

Continue reading “This Message Will Self-Destruct In 5 Seconds” →

Creating A 2D Film With 3D Printed Frames

October 18, 2014 by Sarah Petkus 11 Comments

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!

Reverse Engineering A Bathroom Scale For Automated Weight Tracking

October 18, 2014 by Rick Osgood 16 Comments

[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.