Day: August 28, 2016

Hackaday Prize Entry: Automated Hydroponics

August 28, 2016 by 25 Comments

This team project for the Hackaday Prize is a solution to a rather important problem. Imagine growing plants for use as biomarkers for pollution. It’s a great idea, but how do you grow the plants in the first place? This team is building a space-saving hydroponic system that packs the most green into the least amount of space. It’s simple, and can be built almost entirely with parts from the local home supply store.

The design of this hydroponic system is based on a few PVC pipes, arranged vertically, joined together with a few 90 degree bends. In each course of pipe, a few holes are drilled to accept a plastic cup. This cup is filled with some sort of growing medium, and the Genuino-based controller takes care of everything else. Watering the plants, turning the lights on and off, and recording the nutrient concentration of the water is all possible with a simple microcontroller.

Right now the team has a huge stack of perforated PVC pipe and a Genuino-based brain box that takes care of everything plants need. It’s going to take a bit of time for the plants to grow, but this is still one of the most compact hydroponic systems we’ve seen.

You can check out a video of the entire setup below.

Continue reading “Hackaday Prize Entry: Automated Hydroponics” →

The Most Traveled Security Screwdriver, A Hacker’s Tale

August 28, 2016 by 54 Comments

Nespresso is a variant of disposable single serve coffee pods with an extensive, expensive, and proprietary accessory line. After selling inconvenient bits of his soul for convenience and, admittedly, fairly tasty shots of coffee, [Chriss Lott] was predictably betrayed by his Nespresso Jura coffee machine. 

Rather than simply exchange more local currency for a replacement revenue guarantee for the Nestle conglomerate, he did what any self-respecting hacker would do and tried to fix it himself. Unfortunately he quickly found their cunningly oval shaped security screws to be more trouble than his time was worth. He listed his remaining coffee pods for free on craigslist and decided to toss the machine in the planned obsolescence receptacle which comes standard in any civilized home.

This is where our story would end were it not for the kindness of a fellow hacker. [Dave H] was browsing through craigslist when he spotted the sad tale. However, possessing a different skillset from [Chris], [Dave] had solved the particular oval shaped conundrum with a security screwdriver hand made from an old bolt. He answered his fellow hacker’s vaguely ardent plea and mailed the converted bolt over to [Chris]’s house.

With the proper tool in hand, [Chris] quickly discovered that all that was standing between him and his convenient coffee was a bit of schmoo between the cost cutting membrane switch and its mating pad on the circuit board. With the practically free repair complete, the machine happily vibrated back to life and produced coffee as if its planned obsolescence wasn’t for another few years. We assume a Nestle engineer was thrown into the pit on principle for this loss (they, of course, are evil enough to have a pit).

We’re not sure how the story proliferated through the internet, but we do know that it was inspirational to many convenient caffeine deprived hackers with similar problems. [Chris] found himself the hub in a network of circumnavigating security screw circumventing hackers.

[Dave]’s hacked bolt was the first to go on an adventure resulting in the repair of many machines before the postmen lost it under a cart, standard procedure. A replacement was purchased from an eBay seller for a hefty $40 american dollars and took up the journey where it left off. Others sent in guides on making the tool for those unwilling to wait for one to be shipped. In fact, even the maker of the $40 dollar tool weighed in on the issue. Apparently he was unaware that the consumer and commercial Nespresso machines used the same tools. A hacker himself, he ran a listing of the custom tool at a quarter of the price for the home repairman and another for the commercial appliance at the higher price.

The whole page is an entertaining read, for a certain kind of person, about appliance repair, reverse engineering, and camaraderie. Happily, the hub is still alive. If you find yourself with an oval screw which needs turning, get in touch with [Chris] and a strange community’s kindness will have a nomadic security bit crossing nations your way soon.

Hackaday Links: August 28, 2016

August 28, 2016 by 19 Comments

E-paper looks awesome, but it’s a pain to work with. You need only look at the homebrew implementations of e-paper drivers and the mess of SMD components for proof of that. [jarek] wanted to play around with e-paper and developed this tiny little driver for a Teensy. It’s a fun toy, and the simplest possible circuit necessary to drive this particular e-paper module.

I am once again asking if anyone knows where to buy this computer case. No, not a complete system – I just want the case, folding keyboard, and monitor integrated into an mATX enclosure.

Back in 1985, a young [Matthias Wandel] built a remote control forklift out of a few windshield wiper motors, wood, and not much else. He’s rebuilt this toy recently, just to prove you can build anything with a stack of plywood and a wood gear template generator.

More Adafruit muppets they probably can’t call muppets. Yaaay. This time it’s J is for Joule. Watts that? A second.

The Raspberry Pi Project, one of our favorite projects in the Hackaday Prize that uses a Raspberry Pi, one of the most liked, viewed, and followed projects on Hackaday.io, and a technological tour de force the likes of which have not been seen since the invention of the steam engine got an update this week. [Arsenijs] and the rest of the Raspberry Pi Project team have released a version of their Raspberry Pi pinout helper. Previously, this tool was only used internally to the project, but since this pinout helper has such far-reaching utility they’ve decided to release a public version. Truly, they are kings among men.

This is possibly the coolest use of stacked plywood I’ve ever seen. It’s a spiral staircase, with each step made of 12 layers of plywood. The ‘spine’ of this staircase is a 3″ sch 40 steel pipe, with a proper foundation. The layer of ply are adhered to the pipe with construction adhesive, and each layer of ply is glued together with wood glue. No, it’s not up to code yet, but it was cheaper to build than just buying a spiral staircase.

[Brek] wrote a graphics library for the ubiquitous 128×64 monochromatic LCDs. It’s written for PICs, but damned if we can’t find a link to the library itself. Hopefully [Brek] will jump in the comments below.

Those really, really cheap ESP8266 modules only have 512kB of Flash in them. Here’s how you upgrade those modules to 4MB. You can do it without a hot air gun, and all you need is a few cheap Flash chips.

Here’s a sound card for a Raspberry Pi. No, that’s not a completely dumb idea. This sound card uses quality op-amps, 24-bit ADCs and DACs, and has MIDI. If you’re experimenting with Pure Data or any other Linux audio toy, this could be a useful addition to your Pi stack.

Open Source SNES To USB Converter Lets You Emulate Legally

August 28, 2016 by 59 Comments

[Andrew Milkovich] was inspired build his own Super Nintendo cartridge reader based on a device we covered an eternity (in internet years) ago. The device mounts a real cartridge as a USB mass storage device, allowing you to play your games using an emulator directly from the cart.

This uses a Teensy++ 2.0  at its core. [Andrew] had to desolder the EEPROM pins from the SNES cartridge and reverse engineer the pinouts himself, but the end result was a device that could successfully read the cartridge without erasing it, no small accomplishment. The finished cartridge reader is build on some protoboard and we’d like to complement [Andrew] on his jumper routing on the underside of that board.

Of course, the experience of any console is just not the same without the original controller. So [Andrew] went a step further and made his own SNES controller to USB converter. This had the venerable Atmel ATmega328 at its core, and can be used separate from the cartridge reader if desired.

Stop Buying Expensive Circular Saw Blades, Use Paper Instead

August 28, 2016 by 54 Comments

[John Heisz] was contemplating the secrets of the universe when an errant thought led him to wonder, could I use a sheet of paper as the blade in my table saw?

He takes a sheet of regular printer paper, draws a circle on it the same diameter as his regular blades, and cuts it out. He then bolts it into place on the spindle, slots in the table saw insert for really really thin kerf blades, and fires it up.

The blade is surprisingly dangerous. One would maybe expect a paper blade to be minimally damaging to a finger at best, but it quickly shows itself to be capable of tearing through paper and cutting through wood at a reasonable clip. Since the paper is minimally conductive, a SawStop couldn’t save someone from a lack of caution.

The blade finally meets its match half way through a half-inch thick piece of wood scrap. Wood and paper dust explode outward as the experiment ends. Video after the break.

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Dirt Cheap VR Gun With Tracking For $15 Of Added Hardware

August 28, 2016 by 2 Comments

Virtual reality doesn’t feel very real if your head is the only thing receiving the virtual treatment. For truly immersive experiences you must be able to use your body, and even interact with virtual props, in an intuitive way. For instance, in a first-person shooter you want to be able to hold the gun and use it just as you would in real reality. That’s exactly what [matthewhallberg] managed to do for just a few bucks.

This project is an attempt to develop a VR shooting demo and the associated hardware on a budget, complete with tracking so that the gun can be aimed independent of the user’s view. [matthewhallberg] calls it The Oculus Cardboard Project, named for the combined approach of using a Google Cardboard headset for the VR part, and camera-based object tracking for the gun portion. The game was made in Unity 3D with the Vuforia augmented reality plugin. Not counting a smartphone and Google Cardboard headset, the added parts clocked in at only about $15.

ESP8266 on FiducialUsing corrugated cardboard and a printout, [matthewhallberg] created a handheld paddle-like device with buttons that acts as both controller and large fiducial marker for the smartphone camera. Inside the handle is a battery and an ESP8266 microcontroller. The buttons on the paddle allow for “walk forward” as well as “shoot” triggers. The paddle represents the gun, and when you move it around, the smartphone’s camera tracks the orientation so it’s possible to move and point the gun independent of your point of view. You can see it in action in the video below.

Tracking a handheld paddle with a fiducial marker isn’t a brand new idea; We were able to find this project for example which also very cleverly simulates a trigger input by making a trigger physically alter the paddle shape when you squeeze it. The fiducial is altered by the squeeze, and the camera sees the change and registers it as an input. However, [matthewhallberg]’s approach of using hardware buttons does allow for a wider variety of reliable inputs (move and shoot instead of just move, for example). If you’re interesting in trying it out, the project page has all the required details and source code.

This isn’t [matthewhallberg]’s first attempt and getting the most out of an economical Google Cardboard setup. He used some of the ideas and parts from his earlier DIY Virtual Reality Snowboard project.

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Bombing The Sky For The Sake Of Radio

August 28, 2016 by 27 Comments

If you are familiar with radio propagation you’ll know that radio waves do not naturally bend around the earth. Like light and indeed all electromagnetic radiation if they are given a free space they will travel in a straight line.

At very high frequencies this means that in normal circumstances once a receiver moves over the horizon from a transmitter that’s it, you’re out of range and there can be no communication. But at lower frequencies this is not the case. As you move through the lower end of the VHF into the HF (Short Wave) portion of the spectrum and below, the radio signal routinely travels far further than the horizon, and at the lower HF frequencies it starts to reach other continents, even as far as the other side of the world.

Of course, we haven’t changed the Laws Of Physics. Mr. Scott’s famous maxim still stands. Radio waves at these frequencies are being reflected, from ionised portions of the atmosphere and from the ground, sometimes in multiple “hops”. The science of this mechanism has been the subject of over a hundred years of exploration and will no doubt be for hundreds more, for the atmosphere is an unreliable boiling soup of gasses rather than a predictable mirror for your radio waves.

Radio amateurs have turned pushing the atmosphere to its limits into a fine art, but what if you would prefer to be able to rely on it? The US military has an interest in reliable HF communications as well as in evening out the effects of solar wind on the ionisation of the atmosphere, and has announced a research program involving bombing the upper atmosphere with plasma launched from cubesats. Metal ions will be created from both chemical reactions and by small explosions, and their results on the atmosphere will be studied.

Of course, this isn’t the first time the upper atmosphere has been ionised in military experiments. Both the USA and the USSR exploded nuclear weapons  at these altitudes before the cessation of atmospheric nuclear testing, and more recently have directed high power radio waves with the aim of ionising the upper atmosphere. You may have heard of the USA’s HAARP project in Alaska, but Russia’s Sura Ionospheric Heating Facility near Nizhniy Novgorod has been used for similar work. It remains to be seen whether these latest experiments will meet with success, but we’re sure they won’t be the last of their kind.

We’ve looked at radio propagation in the past with this handy primer, and we’ve also featured a military use of atmospheric reflection with over-the-horizon radar.

Fishbowl Starfish Prime upper atmosphere nuclear test image via Los Alamos National Laboratory. As an image created by an officer or employee of the United States government as part of their official duties this image is in the public domain.