Bending The Light

October 28, 2016 by Adam Fabio 17 Comments

Ruled Hyperboloid CC Prof. William McCallum

Everyone knows you can’t visibly bend light over short distances in free air. Or can you? [Jack Pearse] has figured out a way to do it though, or at least make it appear that way. He does it by combining a trick of math and a trick of the eye. The secret is the hyperboloid, a geometric construct described by a quadratic equation. [Jack’s] creation is more specifically a hyperboloid in one sheet. This type of structure allows straight lines to create a an overall curved surface. Hyperboloids have been used by architects and in construction for years, often in tall structures like water towers.

If a bunch of straight steel beams can form a curved shape, lasers should be able to pull off the same effect. By employing persistence of vision, [Jack] was able to create his hyperboloid with only 10 small lasers. The lasers are mounted on the rim of a bicycle wheel and carefully aimed. The wheel is spun up with using an electric bicycle motor. [Jack] kept things safe by building a centrifugal switch. The switch powers up all the lasers in when the tire is spinning. This ensures no one can be hit by a static beam.

Once the wheel is spinning, all you need is a bit of smoke or haze in the room. The spinning lasers combine to form the hyperboloid shape. You can see the project in action in the video after the break.

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Don’t Make Your Battlebot Out Of A Pumpkin

October 28, 2016 by Elliot Williams 8 Comments

It’s that time of year again. The nights are getting longer and the leaves are turning. The crisp fall air makes one’s thoughts turn to BattleBots: pumpkin-skinned BattleBots.

pumpkin-combat-robot-1azglafagdsmkv-shot0005 — Kids these days can’t even draw without a computer

If you’re asking yourself, “could a laser-cut plywood bot, sheathed in a pumpkin, stand up against an all-metal monster”, you haven’t seen BattleBots before. Besides the hilarious footage (see video embedded below), a lot of the build is documented, from making a CAD model of a pumpkin to laser-cutting the frame, to “testing” the bot just minutes before the competition. (That has to be a good idea!)

The footage of the pumpkinbot’s rival, Chomp, is equally cool. We love that the hammer weapon is accelerated so quickly that Chomp actually lifts in the air, just as Newton would have predicted. We’re not sure if the fire weapon is good for anything but show, and facing plywood pumpkinbots, but we love the effect.

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Apple Sucks Now, Here’s A ThinkPad Buyer’s Guide

October 28, 2016 by Brian Benchoff 247 Comments

For the last decade, Macs have been running a UNIX-ish operating system on x86 processors. They’ve been fantastic developer’s machines, and the MacBook Pro is the de facto standard laptop issued to all developers, all hackathon attendees, and arguably, anyone who does real work with a computer.

This week, Apple unveiled the latest MacBook Pro and provided more evidence Steve Jobs actually knew what he was doing. Fifteen hundred bones will get you a MacBook Pro with a last-gen processor, an Escape key, a headphone jack, and two Thunderbolt 3 ports (with one port required for charging). The next model up costs $1800, ditches the Escape key for a dedicated emoji bar, and includes four Thunderbolt 3 ports.

In the past, I have defended people who choose MacBooks as their laptop of choice. A MacBook is a business-class laptop, and of course carries a higher price tag. However, Apple’s latest hardware release was underwhelming and overpriced. If you’re looking for a new laptop, you would do well to consider other brands. To that end, here’s a buyer’s guide to ThinkPads, currently the second most popular laptop I’ve seen with the dev/hacker/code cracker crowd.

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ODROID XU4 Runs Cool As Water

October 28, 2016 by Gerrit Coetzee 11 Comments

We did a bit of looking through the ODROID forums and apparently it’s quite possible to squeeze an impressive amount of performance out of these little single board computers, if you don’t mind them getting boiling hot.

Now, some people have taken pedestrian routes. It’s a low power single board computer after all. A bigger heatsink or a fan appears to be enough for most. [Micky] and a friend, however, decided this is a problem that can only be solved with a healthy bit of overengineering.

Using a water cooler meant for a full CPU, a modified chipset cooling block (meant for the North or South Bridge), a liberal application of plexiglass, and some thermal paste they manage to triple the cost of their computer set-up with this wonderfully overkill desk ornament.

Now it can do all the things a Raspberry Pi can do, faster and watercooled.

Not Quite 101 Uses For An ATX Power Supply

October 28, 2016 by Jenny List 82 Comments

The PC power supply has been a standard of the junk box for the last couple of decades, and will probably continue to be for the foreseeable future. A product that is often built to a very high standard and which will give years of faithful service, yet which has a life of only a few years as the PC of which it is a part becomes obsolete. Over the decades it has evolved from the original PC and AT into ATX, supplying an ever-expanding range of voltage rails at increasing power levels. There have been multiple different revisions of the ATX power supply standard over the years, but they all share the same basic form factor.

So a pile of ATX supplies will probably feature in the lives of quite a few readers. Most of them will probably be old and obsolete versions of little use with today’s motherboards, so there they sit. Not small enough to ignore, yet Too Good To Throw Away. We’re going to take a look at them, try to work out what useful parts they contain, and see a few projects using them. Maybe this will provide some inspiration if you’re one of those readers with a pile of them seeking a purpose.

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Duckhunting – Stopping Rubber Ducky Attacks

October 28, 2016 by Brian Benchoff 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.

The Pumpkin Noti-Fire

October 28, 2016 by Jenny List 10 Comments

Everyone has an episode somewhere in their youth involving the use of an aerosol spray as an impromptu flamethrower. Take some mildly inebriated teenagers, given them a deodorant can and a box of matches, and sooner or later one or two of them are going to lose their eyebrows.

For most of us an amusing teenage episode is how the aerosol flamethrower remains. Not for [Mike Waddick] though, when last week’s DDoS attack on DNS infrastructure took away his ability to work his, attention turned to a Halloween project. He created a carved pumpkin that spits fire as a notification signal when a text or an email is received.

Key to the project is the Glade Automatic Spray Air Freshener. This is a battery-powered device with an aerosol can that is operated by either an electronic timer or a push-button switch. Remove the switch, and its line is revealed as an active low trigger for the spray. [Mike] replaced the switch with a line from a microcontroller and put a lit tea-light candle in front of the nozzle for fully controllable (if not entirely safe) flamethrower fun. Early tests proved the concept, so it only remained for the pumpkin to be carved and the system installed.

The microcontroller used in this case was the Lightblue Bean, though almost any similar board could have been put in its place. Notifications were processed via Bluetooth from an iPhone via ANCS (Apple Notification Center Service), which the Bean could query to trigger its fiery alerts. There is a brief video showing the device in action singeing [Mike]’s hand, which we’ve placed below the break.

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