Vote With Your Feet

November 12, 2016 by 25 Comments

Gamifying life is silly, fun, and a great way to interact with those strangers who you pass everyday. Here’s one example that might just pop up along your next walk to work. It’s a way to take a very unscientific straw poll on any topic — you won’t even have to use your hands to cast a ballot.

A group called [Vote With Your Feet] has come up with a novel way of casting ballots. Simply walk down the sidewalk and through one of two doorways, each labeled with either side of a dichotomy. Each doorway is able to count the number of people that pass through it, so any issue imaginable can be polled. They already did vim vs emacs (59 to 27),  and we’d like to see Keynes vs Hayek, or even Ovaltine vs Nesquik. Users can send the machine new issues for the masses to vote on, so the entertainment is quite literally limited only by your imagination.

thumbThe physical build is well documented. Since this is used outside, the choice of a flipdot display (of course always fun to play with) is perfect for this high-contrast in any level of light. Each doorway has a break-beam sensor which is monitored by the Raspberry Pi driving the overhead display (here’s code for it all if you want to dig in).

The point of this art installation like this is to get people to interact with their environment in a novel way, which this project has accomplished exceptionally well. In 3 days, they registered over 10,000 votes which are viewable on their website. If you have a project in mind that calls for data visualization you might want to keep this in your back pocket.

We have also seen other ways that doorways can count people outside of voting, if you’re looking for any inspiration yourself.

Icehat on a Raspberry Pi Zero

Give Your RPi A Cool FPGA Hat

November 5, 2016 by 32 Comments

Need additional, custom IO for your Raspberry Pi? Adding an FPGA is a logical way to expand your IO, and allow for high speed digital interfaces. [Eric Brombaugh]’s Icehat adds a Lattice iCE5LP4K-SG48 FPGA in a package that fits neatly on top of the Raspberry Pi Zero. It also provides a few LEDs and Digilent compatible PMOD connectors for adding peripherals. The FPGA costs about six bucks, so this is one cheap FPGA board.

The FPGA has one time programmable memory, but can also be programmed over SPI. This allows the host Pi to flash the FGPA with the latest bitstream at boot. Sadly, this particular device is not supported by the open source Icestorm toolchain. Instead, you’ll need Lattice’s iCEcube2 design software. Fortunately, this chip is supported by the free license.

Icehat is an open source hardware design, but also includes a software application for flashing a bitstream to the FPGA from the Pi and an example application to get you started. All the relevant sources can be found on Github, and the PCB is available on OSHPark.

While this isn’t the first pairing of a Raspberry Pi and FPGA we’ve seen, it is quite possibly the smallest, and can be built by hand at a low cost.

After The Prize: A Libre Space Foundation

November 4, 2016 by 3 Comments

The Hackaday Prize is the greatest hardware build-off on the planet, and with that comes some spectacular prizes. For the inaugural Hackaday Prize in 2014, the top prize was $196,418. That’s a handsome sum, and with that, the right hardware, and enough time, anything is possible.

The winners of the first Hackaday Prize was the SatNOGs project. The SatNOGs project itself is very innovative and very clever; it’s a global network of satellite ground stations for amateur cubesats. This, in itself, is a huge deal. If you’re part of a student team, non-profit, or other organization that operates a cubesat, you only have access to that satellite a few minutes every day — whenever it’s in the sky, basically. SatNOGs is a project to put directional, tracking antennas everywhere on Earth, all connected to the Internet. This is a project that gives global ground station coverage to every amateur-built cubesat.

It’s been two years since SatNOGs won the Hackaday Prize, so how are they doing now? I caught up with some of the midwest reps of SatNOGs at this year’s Hamvention, and the project is doing very well. The steerable antenna mount designed by the SatNOGs project is fantastic, some of the Earth stations are seeing a lot of use, and the network is growing.

Two years is a long time, and since then SatNOGs has evolved into the Libre Space Foundation, a not-for-profit foundation with a mission to promote, advance and develop free and open source technologies and knowledge for space.

The premier project for the Libre Space Foundation is the UPSat, the first Open Source satellite ever launched. For the last two years, this is what the Libre Space Foundation has been working on, and soon this satellite will be orbiting the Earth. The satellite itself was recently delivered, and next month it will be launched to the International Space Station aboard a Cygnus spacecraft. After that, it will be deployed to low Earth orbit from Nanoracks’ deployment platform on the station.

This is truly an amazing project. SatNOGs brought a network of ground stations to amateur cubesats orbiting the Earth, and now the Libre Space Foundation will put an Open Source satellite into low Earth orbit. All the documentation is available on Github, and this is the best the open hardware movement has to offer. We’re proud to have SatNOGs and the Libre Space Foundation proving that Open Hardware can change the world, and we can only hope this year’s winner of the Hackaday Prize has such an impact.

The HackadayPrize2016 is Sponsored by:

Tools Of The Trade — Injection Molding

November 4, 2016 by 34 Comments

Having finished the Tools of the Trade series on circuit board assembly, let’s look at some of the common methods for doing enclosures. First, and possibly the most common, is injection molding. This is the process of taking hot plastic, squirting it through a small hole and into a cavity, letting it cool, and then removing the hardened plastic formed in the shape of the cavity.

The machine itself has three major parts; the hopper, the screw, and the mold. The hopper is where the plastic pellets are dumped in. These pellets are tiny flecks of plastic, and if the product is to be colored there will be colorant pellets added at some ratio. The hopper will also usually have a dehumidifier attached to it to remove as much water from the pellets as possible. Water screws up the process because it vaporizes and creates little air bubbles.

Next the plastic flecks go into one end of the screw. The screw’s job is to turn slowly, forcing the plastic into ever smaller channels as it goes through a heating element, mixing the melted plastic with the colorant and getting consistent coloring, temperature, and ever increasing pressure. By the time the plastic is coming out the other end of the screw, and with the assistance of a hydraulic jack, it can be at hundreds of tons of pressure.

Finally, the plastic enters the mold, where it flows through channels into the empty cavity, and allowed to sit briefly to cool.  The mold then separates and ejector pins push the part out of the cavity.

Continue reading “Tools Of The Trade — Injection Molding” →

HFSat And The All-HF Amateur Radio Satellite Transponder

November 3, 2016 by 17 Comments

One facet of the diverse pursuit that is amateur radio involves the use of amateur radio satellites. These have a long history stretching back to the years shortly after the first space launches, and have been launched as “piggy-back” craft using spare capacity on government and commercial launches.

Though a diverse range of payloads have been carried by these satellites over the years, the majority of amateur radio satellites have featured transponders working in the VHF and UHF spectrum. Most often their links have used the 2m (144 MHz) and 70cm (430MHz) bands. A few have had downlinks in the 10m (28MHz) band, but this has been as far as they have ventured into the HF spectrum.

A new cubesat designed and built by trainees at the US Naval Academy promises to change all that, because it will feature an all-HF transponder with a 15m (21MHz) uplink and a 10m downlink. To that end it will carry a full size 10m wire dipole antenna. The 30KHz wide transponder is an inverting design intended to cancel out the effects of Doppler shift. In their write-up they provide a fascinating description of many aspects of cubesat design, one which should be of significant interest beyond the world of amateur radio.

If the subject of amateur radio in space interests you, have a look at our series on the matter, first covering the OSCAR satellites, and then our recent feature on its use in manned missions.

[via Southgate ARC]

Duckhunting – Stopping Rubber Ducky Attacks

October 28, 2016 by 51 Comments

One morning, a balaclava-wearing hacker walks into your office. You assume it’s a coworker, because he’s wearing a balaclava. The hacker sticks a USB drive into a computer in the cube next door. Strange command line tools show up on the screen. Minutes later, your entire company is compromised. The rogue makes a quick retreat carrying a thumb drive in hand.

This is the scenario imagined by purveyors of balaclavas and USB Rubber Duckys, tiny USB devices able to inject code, run programs, and extract data from any system. The best way — and the most common — to prevent this sort of attack is by filling the USB ports with epoxy. [pmsosa] thought there should be a software method of defense against these Rubber Duckys, so he’s created Duckhunter, a small, efficient daemon that can catch and prevent these exploits.

The Rubber Ducky attack is simply opening up a command line and spewing an attack from an emulated USB HID keyboard. If the attacker can’t open up cmd or PowerShell, the attack breaks. That’s simple enough to code, but [pmsosa] has a few more tricks up his sleeve. Duckhunter has a ‘sneaky’ countermeasure feature, where one out of every 5-7 keystrokes is blocked. To the attacker, the ‘sneaky’ countermeasure makes it look like the attack worked, where in fact it failed spectacularly.

There are a number of different attacks similar to what the Rubber Ducky can accomplish. Mousejack performs the same attack over Bluetooth. BadUSB is a little more technical, allowing anyone with access to a device’s firmware to turn your own keyboard against you. Because of the nature of the attack, Duckhunter shuts them all down.

Right now the build is only for Windows, but according to [pmsosa]’s GitHub there will be Linux and OS X versions coming.

Sometimes Square Is Square: Basic Machinist Skills

October 25, 2016 by 27 Comments

Is it possible to make an entertaining video about turning a cube of aluminum into a slightly cubier cube? As it turns out, yes it is, and you might even learn something along with the sight gags and inside jokes if you watch [This Old Tony] cover the basics of squaring up stock.

Whether you’re working in wood or metal, starting with faces that are flat, smooth and perpendicular is the key to quality results. [Tony] is primarily a machinist, so he works with a nice billet of aluminum and goes through some of the fundamental skills every metalworker needs to know. When you’re working down to the thousandths of an inch it’s easy to foul up, and tricks such as using a ball bearing between the vise jaws and the stock to prevent canting are critical skills. He covers tramming the mill, selecting which faces to cut and in which order, and ways to check your work on the surface plate and make any corrections if and when things go wrong. Look for cameos by fellow machinist [Abom79] and [Stefan Gotteswinter], including one with [Stefan] in a very compromising position. But a ball in a vise and no [AvE] reference? C’mon!

[Tony] makes a potentially tedious subject pretty entertaining by keeping things light, and we appreciate both the humor and attention to detail. He’s turned out some great videos that we’ve covered before, like making your own springs or a shop-built boring head, and his stuff is really worth checking out.

Continue reading “Sometimes Square Is Square: Basic Machinist Skills” →