Pulsed Power And Its Applications

January 11, 2017 by 43 Comments

Pulsed power is a technology that consists in accumulating energy over some period of time, then releasing it very quickly. Since power equals energy (or work) divided by time, the idea is to emit a constant amount of energy in as short a time as possible. It will only last for a fraction of a second though, but that instantaneous power has very interesting applications. With this technology, power levels of more than 300 terawatts have been obtained. Is this technology for unlimited budgets, or is this in reach of the common hacker?

Consider for example discharging a capacitor. A large 450 V, 3300 uF electrolytic capacitor discharges in about 0.1 seconds (varies a lot depending on capacitor design). Since the energy stored in it is given by 1/2 CV², which gives 334 Joules of energy, the power delivered will be 3340 watts. In fact a popular hacker project is to build large capacitor banks. Once you have the bank, and a way to charge it, you can use it to power very interesting devices such as:

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A portable, 1.25 kJ coilgun by [Jason Murray]

Railguns in particular are subject to serious research. You may have read about the navy railgun, capable of reaching a muzzle speed of more than 4,600 mph (around Mach 6), more than any other explosive-powered gun. Power is provided by a 9-megajoule capacitor bank. The capacitors discharge on two conducting rails, generating an electromagnetic field that fires the projectile along the rails. The rail wear due to the tremendous pressures and currents, in the millions of amperes range, is still a problem to be solved.

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Full-Auto Crossbow Rocks And Rolls On Rubber Bands And Electric Drill

January 11, 2017 by 26 Comments

You’ve got to enjoy any project where the hacker clearly loves what he or she is doing. And when the project is as cool as a motor-driven, rubber band powered, fully automatic crossbow, it’s hard not to laugh along.

A full-auto crossbow is no mean feat, and it took a man with a love for rubber-powered firearms to get it right. [JoergSprave]’s design is based on a rack-and-pinion system and executed mainly in plywood. The main pinion gear is a composite of aluminum and wood, in a bid to increase the life of the mechanism and to properly deal with the forces involved. The pinion, turned by a powerful electric drill, drives the rack back and locks the carrier under the 30-bolt magazine. A rubber-powered follower forces a bolt down and a cam on the pinion trips the sear, the bolt is fired and the cycle continues.

We slowed the video down a bit and it looked to us like the cyclical rate of fire was about 7 rounds per second, or a respectable 420 rounds per minute. Pretty powerful, too, and the accuracy isn’t bad either.

We’ve seen [Joerg]’s inventions before, like this soda bottle Gatling arrow launcher, or his ridiculous machete launcher. We hope he keeps having fun and letting us watch.

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Super Mario Run(s) — Away With Your Money

January 11, 2017 by 37 Comments

If you are an Android user and a big fan of Super Mario beware: there is no Android version! There has been no official news on the Android version yet, let alone a version of the game. There is, however, a version circulating outside of Google Play market that will steal your bank account.

Right now attackers are taking advantage of the game’s popularity and Android users despair to spread malware posing as an Android version of Super Mario Run as they did in the past for Pokemon GO. The trojan is called Android Marcher and has been around since 2013, mostly targeting mobile users financial information. After installation, the application attempts to trick users with fake finance apps and a credit card page in an effort to capture banking details. The malware also locks out Google Play until the user supplies their credit card information.

In this new variant of Marcher, it can monitor the device and steal login data of regular apps, not just banking and payment apps, and send the stolen data back to command and control (C&C) servers. Facebook, WhatsApp, Skype, Gmail, the Google Play store are all vulnerable. Criminals can exploit these stolen accounts to carry out additional fraud.

Zscaler researchers advice is:

To avoid becoming a victim of such malware, it is a good practice to download apps only from trusted app stores such as Google Play. This practice can be enforced by unchecking the “Unknown Sources” option under the “Security” settings of your device.

We may add to turn on “App Verification”. Verify Apps regularly checks activity on your device and prevents or warns you about potential harm. Verify Apps is on by default, as is Unknown Sources turned off. Verify Apps also checks apps when you install them from sources other than Google Play. Of course, there is a privacy trade-off. Some information has to be sent about the apps you install back to Google.

The main advice is: use common sense. It’s common practice for companies to release official apps versions through Google Play and highly unlikely to do it via any other way.

Open Sound Control Of Kitchen Lights

January 10, 2017 by 3 Comments

Controlling the Internet of Things is all about passing information around. Realistically, it doesn’t matter what is used, be it MQTT, HTTP, serial data, whatever, and it doesn’t really matter what data is sent as long as the sender and receiver agree on what the data means. MIDI could be used to pass information back and forth, for example and while MIDI is good for some things, Open Sound Control is a more modern alternative and one area where OSC excels over MIDI is Internet connectivity. [Matt] used OSC to control the lighting he installed in his kitchen.

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ESP8622-1 and Buck Converter

[Matt] had moved in to a new house and wanted some under-cupboard lighting for his kitchen. He got a few cheap warm white LED lights from the Internet and went about wiring them together. For the controller, an ESP8266-1 was used as well as a 12 volt constant-current buck converter. The software runs on the Sming framework, rather than the Arduino framework, and listens for incoming OSC messages. When it receives a command on a specific channel, a callback function turns the lights on and off.  [Matt] also added a switch on the outside of the control box to manually turn the lights on and off.

OSC might not be the right choice for this project, and even [Matt] doesn’t know why he used it, but [Matt] got it working and uses an app on his phone to control it. If he wanted to, he could have used Ableton or another controller to control the lights. (He hasn’t wanted to yet.) OSC is an interesting alternative to MIDI and can also be used with an Arduino without an ethernet shield, or with RFID tags.

Paper Airplane Machine Gun V2.0

January 10, 2017 by 40 Comments

A little over two years ago we posted an amazing contraption that holds a stack of paper sheets, folds them into paper planes, and launches them. There’s now a newer version — the PFM A5 v2.0. It is over a meter long, weighs about 10 kilograms, and features a mind-boggling number of gears and moving parts. Video is embedded below.

In one end travels one sheet of paper after the next. At each stage in the process the paper is folded (symmetrically) and creased by a vertical wheel to make up the keel of the finished plane before launching out the other end. Amazing, and not a jam or “PC Load Letter” error message in sight!

This, of course, has a purpose… junk ads from the sky!

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Taking First Place At IMAV 2016 Drone Competition

January 10, 2017 by 1 Comment

The IMAV (International Micro Air Vehicle) conference and competition is a yearly flying robotics competition hosted by a different University every year. AKAMAV – a university student group at TU Braunschweig in Germany – have written up a fascinating and detailed account of what it was like to compete (and take first place) in 2016’s eleven-mission event hosted by the Beijing Institute of Technology.

AKAMAV’s debrief of IMAV 2016 is well-written and insightful. It covers not only the five outdoor and six indoor missions, but also details what it was like to prepare for and compete in such an intensive event. In their words, “If you share even a remote interest in flying robots and don’t mind the occasional spectacular crash, this place was Disney Land on steroids.”

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How To Add More Games To The NES Classic

January 10, 2017 by 25 Comments

The hype around the NES Classic in 2016 was huge, and as expected, units are already selling for excessively high prices on eBay. The console shipped with 30 games pre-installed, primarily first-party releases from Nintendo. But worry not — there’s now a way to add more games to your NES Classic!

Like many a good hack, this one spawned from a forum community. [madmonkey] posted on GBX.ru about their attempts to load extra games into the console. The first step is using the FEL subroutine of the Allwinner SOC’s boot ROM to dump the unit’s flash memory. From there, it’s a matter of using custom tools to inject extra game ROMs before reburning the modified image to the console. The original tool used, named hakchi, requires a Super Mario savegame placed into a particular slot to work properly, though new versions have already surfaced eliminating this requirement.

While this is only a software modification, it does come with several risks. In addition to bricking your console, virus scanners are reporting the tools as potentially dangerous. There is confusion in the community as to whether these are false positives or not. As with anything you find lurking on a forum, your mileage may vary. But if you just have to beat Battletoads for the umpteenth time, load up a VM for the install process and have at it. This Reddit thread (an expansion from the original pastebin instructions) acts as a good starting point for the brave.

Only months after release, the NES Classic is already a fertile breeding ground for hacks — last year we reported on this controller mod and how to install Linux. Video of this ROM injection hack after the break.

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